Abstract:
The present invention is a wastewater treatment method using dried BOF slag and hydrogen peroxide, wherein hydrogen peroxide is oxidized to generate hydroxyl radicals that reacts with soluble metal contaminants in the sludge such that these contaminants can be adsorb on the catalyst particles and/or eliminated from the wastewater stream by separation techniques. The process can use catalytic oxidation for soluble metals removal. In addition, catalytic oxidation can produce a filtered water saturated with Oxygen and higher in pH resulting in enhanced precipitation of soluble metals when softening agents, such as Sodium Carbonate, are added in a subsequent processing step. Another embodiment of the present invention is a method using ferrous sulfate for removing soluble metals in wastewater, followed by Catalytic Oxidation to remove soluble Fe without addition of metal salts, and removing sulfates by adding Barium Carbonate.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a U.S. National Stage application under 35 USC 371 filing of International Application Number PCT/US2011/063055, entitled “METHOD FOR TREATING A VARIETY OF WASTEWATER STREAMS” filed on Dec. 2, 2011, which claims priority from U.S. Provisional Application Ser. No. 61/458,841, entitled METHOD FOR TREATING A VARIETY OF WASTEWATER STREAMS USING A SOLID METAL OXIDE BY-PRODUCT STREAM filed on Dec. 2, 2010, both are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention is related generally to a method of treating a wastewater stream and, more particularly, to a method of treating a wastewater stream containing metals, organics, suspended solids, sulfates and other contaminants. 
     BACKGROUND OF THE INVENTION 
     The Marcellus Shale is a sedimentary rock formation deposited over 350 million years ago in a shallow inland sea located in the eastern United States where the present-day Appalachian Mountains now stand. This shale contains significant quantities of natural gas. New developments in drilling technology, along with higher wellhead prices, have made the Marcellus Shale an important natural gas resource. 
     In the new hydrofracturing process, high pressure water is forced into the well during the drilling process to break up the shale deposit and release natural gas. This process typically requires from two (2) to seven (7) million gallons (MG) of water to frac a well (drill using high pressure water), and additional 0.1 to one (1) million gallons of water needed for drilling fluids to maintain down-hole hydrostatic pressure, cool the drill head and enable removal of drill cuttings. Approximately twenty to twenty-five percent (20 to 25%) of this water, an average of 1.2 MG, returns to the surface with the natural gas. The return water is heavily contaminated with metals, for example, Barium (Ba), Strontium (Sr), Magnesium (Mg), Calcium (Ca), and Iron (Fe), and in some cases radionuclides. This return wastewater is generated in two (2) stages: i) the first stage is flowback water that returns to the surface with natural gas in one (1) to three (3) weeks after the gas production starts; and ii) the second stage is produced water which continues to flow approximately three (3) weeks after gas production starts, and continues over the life of the well, approximately six (6) years. Usually, approximately twenty-one percent (21%), used in the drilling process returns to the surface as flowback water, approximately 1.06 MG. This frac (frac and produced) water, in addition to the frac fluids added by the gas drilling companies, contain a variety of contaminants such as total dissolved solids, heavy metals, organics and possibly radionuclides. This combination of contaminants can make frac water difficult and expensive to treat. Most of the total dissolved solids (TDS) in flowback water and produced water is due to sodium chloride, and on average, is three (3) to five (5) times saltier than sea water. TABLE A shows the constituents and concentration ranges usually found in untreated samples of frac water. 
     
       
         
               
               
               
             
               
               
               
             
           
               
                 TABLE A 
               
               
                   
               
               
                   
                   
                 Analyte Concentration Ranges 
               
               
                 Sr. No. 
                 Analyte 
                 (mg/L) 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.5-6.5 
               
               
                 2. 
                 Iron (Fe) 
                  10-150 
               
               
                 3. 
                 Barium (Ba) 
                   25-4,000 
               
               
                 4. 
                 Sulfate (SO 4 ) 
                  5-400 
               
               
                 5. 
                 Chloride (Cl) 
                  10,000-150,000 
               
               
                 6. 
                 Sodium (Na) 
                 10,000-50,000 
               
               
                 7. 
                 Strontium (Sr) 
                   100-3,000 
               
               
                 8. 
                 Total Dissolved Solids (TDS) 
                  15,000-250,000 
               
               
                 9. 
                 Calcium (Ca) 
                   500-20,000 
               
               
                 10. 
                 Magnesium (Mg) 
                   100-3,000 
               
               
                 11. 
                 Total Suspended Solids (TSS) 
                   100-1,500 
               
               
                   
               
             
          
         
       
     
     The above-mentioned frac water must be treated and disposed of properly. Some of the current disposal practices for frac water include: (1) storing the frac water in large ponds and tanks and reusing after being blended with clean water; (2) loading the frac water into trucks/trailers and sending/transporting it to external centralized treatment facilities for disposal or disposing in underground deep-well injection wells; and (3) treating the frac water on-site by means of known on-site treatment technologies such as Evaporation, Crystallization, Distillation, and/or multiple selective precipitation steps of five (5) or more stages, etc. Traditional treatment techniques such as evaporation and selective precipitation appear not to be economically feasible options for treating Marcellus shale wastewater. 
     The various wastewater treatment methods for treating Marcellus shale frac water is generally costly with higher energy consumptions, and the effectiveness and efficiency at removing the contaminants is not very good. Further, because the amount of gas wells in the Marcellus shale area are increasing at a substantial rate, there is a need in the industry to find an effective and cost efficient way to treat frac water generated from gas production. 
     It is advantageous to provide a cost-efficient, portable and effective process that treats frac water streams containing waste metal elements and/or compounds using a by-product such as BOF sludge generated during steel production. The advantages of this wastewater treatment process include, but not limited to, significant metals reduction, recovery and re-use of regenerated BOF sludge as a catalyst, breakdown of organic compounds including recalcitrant organic compounds, and the use of readily available equipment components that do not require specialty materials and fabrication techniques. 
     The gas companies vary as to the water quality suitable for drilling purposes. A suitable frac water treatment process does not necessarily have to meet “the water quality suitable for drilling,” if after adding fresh water the final water quality meets the drilling standards for the client. Generally, treated water available for drilling is approximately ⅓ rd  of the total volume required. Therefore, any final treated water quality can be three (3) times higher than the acceptable limits and be accepted for recycling, since dilution will bring the water quality into the acceptable range. 
     The following is an example of a water quality acceptable for recycling after treatment by a Major Gas Producer. 
     
       
         
               
               
               
               
             
               
               
               
               
             
           
               
                 TABLE B 
               
               
                   
               
               
                 Sr. No. 
                 Analyte 
                 Units 
                 Analyte Concentration 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 — 
                 6.0-8.5 
               
               
                 2. 
                 Iron (Fe) 
                 mg/L 
                 0.3-4.0 
               
               
                 3. 
                 Barium (Ba 2+ ) 
                 mg/L 
                 163-200 
               
               
                 4. 
                 Strontium (Sr 2+ ) 
                 mg/L 
                 323-377 
               
               
                 5. 
                 Calcium (Ca 2+ ) 
                 mg/L 
                 226-350 
               
               
                 6. 
                 Magnesium (Mg 2+ ) 
                 mg/L 
                 595-700 
               
               
                 7. 
                 Sodium (Na + ) 
                 mg/L 
                 35,050-50,000 
               
               
                 8. 
                 Potassium (K + ) 
                 mg/L 
                   966-1,529 
               
               
                 9. 
                 Chloride (Cl − ) 
                 mg/L 
                 55,400-65,000 
               
               
                 10. 
                 Sulfate (SO 4   2− ) 
                 mg/L 
                  0-200 
               
               
                 11. 
                 Hardness 
                 mg/L 
                 3,003-3,260 
               
               
                   
                   
                 as CaCO 3   
                   
               
               
                 12. 
                 Total Suspended Solids (TSS) 
                 mg/L 
                 138-245 
               
               
                   
               
             
          
         
       
     
     SUMMARY OF THE INVENTION 
     Hydrogen Peroxide (H 2 O 2 ) is a powerful oxidant, but at low concentrations (&lt;0.1%) its reaction kinetics are too slow to degrade many contaminants of concern. The present invention proposes to use a mix of catalytic oxidation to generate the (OH.) free radical, resulting in the adsorption of aqueous metal contaminants on the surface of the catalyst and sodium carbonate and other chemical precipitation techniques. Dried Basic Oxygen Furnace (BOF) sludge or slag is used to catalyze (H 2 O 2 ). 
     BOF sludge (sludge and slag are interchangeably used herein) used in this experiment has submicron particles in the nano-range. The extremely fine submicron particles mimic the behavior of soluble Fe 3+  and Fe 2+  in catalyzing the breakdown of hydrogen peroxide. The present invention uses BOF sludge in the presence of hydrogen peroxide to remove metals, as well as organics, in wastewater streams such as wastewater generated during the drilling for natural gas in the Marcellus shale (frac water), which is unique in that catalytic oxidation is used principally to remove metals and not necessarily organics from wastewater such as frac water. In addition, the present invention uses catalytic oxidation in a synergistic role to remove metals, namely iron (Fe) in the catalytic step while producing “conditioned” wastewater; such that, when the partially treated water from the first step is transferred to a second step in which sodium carbonate (Na 2 CO 3 ) is added, precipitation of multiple metals (Ba, Ca and Sr), at large percentage removal, is achieved at a narrow pH range between 6.0 and 8.5. “Wastewater conditioning” is the result of the following process: performing a First Process Step of catalytic oxidation, as shown in  FIG. 1 , increases the overall efficiency of metal removals in the Second Processing Step (filtered pre-treated water from the First Processing Step). The catalyst used initiates and maintains reactive in the Second Processing Step which creates a strong oxidation-reduction environment in the Second Processing Step. This leaching of basicity, the existence of an enhanced oxidation-reduction environment in the catalytic oxidation step resulting from metals such as Fe 2+  undergoing oxidation to Fe 3+  and vice versa shown below:
 
Fe 2+ +H 2 O 2 →Fe 3+ +OH − +OH*
 
Fe 3+ +H 2 O 2 →Fe 2+ +*OOH+H + 
 
     The oxygenation of the water caused by the sum of the reactions generating oxygen (O 2 ) resulting in O 2  saturated water leaving the First Processing Step enhance the bulk precipitation of cations (Ca 2+ , Ba 2+ , and Sr 2+ ) by Na 2 CO 3  precipitation. The water leaving the catalytic oxidation step continues to degas and effervesce even after the catalyst particles are filtered. Catalytic oxidation continues in the oxygen (O 2 ) rich water in the Second Processing Step due to the presence of minutes amounts of submicron metal oxide particles possibly in the nano-particle range continuing to undergo Fenton-like reactions and forming submicron metal hydroxides polymer chains. 
     In basic oxygen steel making, molten iron from a blast furnace is charged into a basic oxide furnace (BOF), which is used for the final refinement of the iron into steel. BOF slag is one type of pollutant waste or by-product resulting from the different steps in steel production. The BOF sludge is typically disposed of by landfilling. Very limited efforts have been made in recycling BOF slag. 
     BOF slag can be used by adding hydrogen peroxide (H 2 O 2 ) wherein the hydrogen peroxide (H 2 O 2 ) is oxidize to generate hydroxyl radicals (OH.) as discussed above, which in turn reacts with metals contaminants, as well as organics, in the sludge such that these contaminants can be oxidized. An example of a BOF Sludge composition is provided below in Table C. 
     
       
         
               
               
               
             
           
               
                 TABLE C 
               
               
                   
               
               
                 Composition 
                 Formulas 
                 Weight % 
               
               
                   
               
             
             
               
                 Fe-rich 
                 FeO, Fe 2 O 3 , Fe 3 O 4   
                  6-48 
               
               
                 Fe/Zn-rich 
                 ZnO, ZnFe 2 O 4   
                  5-30 
               
               
                 Ca/Fe-rich 
                 CaO, CaFe 2 O 4   
                  5-20 
               
               
                 Fe/Mg-rich 
                 MgFe 2 O 4   
                 2-8 
               
               
                 Si/Mg-rich 
                 SiMg 2 O 2   
                 2-8 
               
               
                 Ca-rich 
                 CaO 
                  3-52 
               
               
                 Si-rich 
                 SiO 
                 0.5-16  
               
               
                   
               
             
          
         
       
     
     The present invention provides for a method of treating a wastewater stream using BOF slag and hydrogen peroxide (H 2 O 2 ) wherein the hydrogen peroxide (H 2 O 2 ) is oxidize to generate hydroxyl radicals (OH.) in a Fenton-like reaction which, in turn, reacts with metal contaminants in the sludge forming hydroxides such that these contaminants can be further adsorb on the BOF sludge particles and subsequently eliminated from the wastewater stream by separation techniques known in the art. 
     The present invention also provides for a method of treating a wastewater stream containing soluble iron (Fe) or barium (Ba) to remove the Fe or Ba from such a stream. 
     The present invention provides for a method to condition the frac water in the first catalytic oxidation step such that when this step is followed by carbonate precipitation and other similar precipitation techniques known in the art, the efficiency of removal of the mixed metals divalent cations is enhanced. 
     The present invention also provides a method for using Ferrous Sulfate, given sulfates effectiveness in forming insoluble salts with divalent cations, while providing a method for Barium addition, which would scavenge residual sulfates and precipitate the sulfate as barium sulfate while keeping the barium to acceptable levels in the treated frac water, thus meeting the acceptable water criteria discussed. 
     The present invention is capable of meeting the water quality by achieving significant reductions in the scale forming chemicals concentration within the limits specified above. The present invention produces treated water that meets the desired Sodium (Na+), Chloride (Cl−) (salt) and Sulfate (SO 4   2− ) concentrations by diluting the treated frac water with fresh make-up water required to meet the total water volume required to drill a well. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For the present invention to be easily understood and readily practiced, the invention will now be described, for the purposes of illustration and not limitation, in conjunction with the following figure, wherein: 
         FIG. 1  is an illustration of one embodiment of the present invention including a two-step process for treating Frac Water, wherein the first processing step is Catalytic Oxidation followed by Magnetic Separation or Filtration, and the second processing step is Metal Precipitation by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration; 
         FIG. 2  is an illustration of a baseline case of the second processing step of the embodiment shown in  FIG. 1 . 
         FIG. 3  is an illustration of a baseline case of Catalytic Adsorption followed by Magnetic Separation or Filtration, which is a baseline case for  FIGS. 1 ,  4  and  5 . 
         FIG. 4  is an illustration of another embodiment of the present invention including a three-step process for recovering rich barium/iron sludge, wherein the first processing step is Catalytic Oxidation followed by Magnetic Separation or Filtration, second processing step is Desorption of the Barium and soluble Fe, and third processing step is Precipitation of Barium and soluble Fe as carbonates; and 
         FIG. 5  is an illustration of another embodiment of the present invention including a three-step process for recovering rich barium/iron sludge, wherein the first processing step is Metal Precipitation by Ferrous Sulfate followed by Filtration, second processing step is Catalytic Oxidation at high pH followed by Filtration, and third processing step is Sulfates Precipitation by Barium Carbonate followed by Filtration. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention will be illustrated with examples of wastewater treatment processes, and it is not intended to limit the present invention to disclosed embodiments. 
     Now turning to  FIG. 1  that shows two (2) processing steps for treating frac water. Each of these processing steps consists of two (2) unit operations. 
     In the first processing step, the first unit operation is catalytic oxidation  100 . In this unit operation, the wastewater D (e.g., frac water) is added to the Catalytic Oxidation Tank/Reactor  100  from the wastewater storage tank/impoundment  40  followed by adding measured amounts of dried BOF Slag (Catalyst) C (Catalyst to Frac Water ratio=1-300 g/L), and Hydrogen Peroxide G (to produce a 0.1-2.0 M solution). After that, the mixture is stirred continuously. The Catalytic Oxidation unit operation  100  produces reactions because of the reaction between Iron (Fe) particles in the BOF Slag (Catalyst) C and Hydrogen Peroxide G. This reaction generates the hydroxyl free radicals (OH.), which is capable of oxidizing organics, metals, and possibly radionuclides. One embodiment of the removal mechanism for this unit operation is a combination of chemical and electrolytic mechanisms: catalytic oxidation, colloidal co-precipitation and metals adsorption onto the catalyst (BOF Slag particles) surface. The Catalytic Metal Slurry T is then transferred to physical separation processes such as magnetic separation unit  80  or filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). The typical reaction time for this unit operation is thirty (30) minutes to three (3) hours. 
     In the first processing step, the second unit operation is a physical separation unit such as a magnetic separation  80  or filtration  60 . In this unit operation, the catalytic metal slurry T from the catalytic oxidation tank/reactor  100  is pumped or gravity fed to the magnetic separation unit  80  or filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These physical separation units separate the treated frac water Q from the catalytic metal slurry T and produce a catalytic metal sludge S. The water recovery for this unit operation is 80 to 90%. This catalytic metal sludge S can then be either disposed in a secured landfill W or recycled in a catalyst regeneration process  90 . The treated frac water Q contains lower amounts of Iron (Fe), Barium (Ba), and Total Suspended Solids (TSS). 
     In the second processing step, the first unit operation is metal precipitation by Carbonate(s)  110 . In this unit operation, the treated frac water from first processing step Q is added to the Metal Precipitation Tank/Reactor  110  followed by adding measured amounts of Carbonate(s) (e.g., Na 2 CO 3 ) (H) (Na 2 CO 3  to Frac Water ratio=1-100 g/L). After that, the mixture is stirred continuously. Carbonate(s) addition precipitate divalent metals such as Barium, Strontium, Calcium, Magnesium and other metals as insoluble metals salts (i.e., barium carbonate, strontium carbonate, calcium carbonate, magnesium carbonate, etc.). The typical reaction time for this unit operation is thirty (30) minutes to one (1) hour. After the metal precipitation unit operation is complete, the carbonate metal slurry P is transferred to a physical separation unit such as a Filtration unit  60 . 
     In the second processing step, the second unit operation is filtration  60 . In this unit operation, the carbonate metal slurry P from the metal precipitation tank/reactor  110  is pumped or gravity fed to the filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These filtration units separate treated frac water U from the slurry and produce a filtered sludge R. The water recovery for this unit operation is 85 to 95%. The filtered sludge (R) can then be disposed in a secured landfill. The treated frac water (U) contains lower amounts of Iron (Fe), Barium (Ba), Calcium (Ca), Magnesium (Mg), Strontium (Sr), Sulfate (SO 4 ), Total Suspended Solids (TSS), and Hardness (as CaCO 3 ) than the wastewater, such as frac water. 
     One embodiment of this present invention includes a composition for the first (1 st ) Processing Step—Catalytic Oxidation followed by Magnetic Separation or Filtration Catalyst to include Frac Water ratio=1-300 g/L, H 2 O 2  Concentration=0.1-2 M solution, and Catalyst to H 2 O 2  (100%) ratio=0.25-7 g/g; and the second (2 nd ) Processing Step—Metal Precipitation by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration to include Na 2 CO 3  to Frac Water ratio=1-100 g/L. 
     Another embodiment of this present invention includes a composition for the first (1 st ) Processing Step—Catalytic Oxidation followed by Magnetic Separation or Filtration Catalyst to include Catalyst to Frac Water ratio=20-30 g/L, H 2 O 2  Concentration=3-7 M solution, and Catalyst to H 2 O 2 *(100%) ratio=5.3-7.5 g/g; and the second (2 nd ) Processing Step—Metal Precipitation by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration to include Na 2 CO 3  to Frac Water ratio=40-45 g/L. 
     The values of concentration of catalyst and H 2 O 2  shown above are high are used when high Barium removal levels are not achieved with lower levels of concentrations as used in Process 1 (Table I, II, III and IV) to achieve high barium removal (more than 95%) in 2 nd  processing step (see Table I, II, III, and IV). 
     Yet another embodiment for this present invention (see Tables I, II, III, and IV) includes a composition for the first (1 st ) Processing Step—Catalytic Oxidation followed by Magnetic Separation or Filtration Catalyst to include Catalyst to Frac Water ratio=25 g/L, H 2 O 2  Concentration=0.1M solution, and Catalyst to H 2 O 2  (100%) ratio=7 g/g; and the second (2 nd ) Processing Step—Metal Precipitation by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration to include Na 2 CO 3  to Frac Water ratio=43.22 g/L. 
     Experimental trials 1, 2, 3, and 4 of these present invention (two-step unit process) are presented Tables I, II, III, and IV below. 
     Experimental Trial 1 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=1 hour 
     3. Catalytic Metal Sludge (S)=70 gm 
     4. Treated Frac Water (Q)=1,470 mL 
     2 nd  Processing Step—Metal Precipitation by Carbonate(s) (e.g., Na 2 CO 3 ) Followed by Filtration: 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=570 mL 
     2. Reaction time (τ)=38 min (0.63 hour) 
     3. Filtered Sludge (S)=74 gm 
     4. Treated Frac Water (U)=520 mL 
     Note: In this unit operation, 570 mL was used from Treated Frac Water (Q). The remaining water was used for water testing. 
     See Table I below for the Experiment Trial 1 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                 1 st  Processing Step 
                 2 nd  Processing 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 25 g/L 
                 Step 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                 Na 2 CO 3  to 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 7 g/g 
                 Frac Water 
                   
               
             
          
           
               
                   
                   
                   
                   
                 Treated 
                 ratio = 
                 Analyte Removal (%) 
               
             
          
           
               
                   
                   
                 Untreated 
                 Diluted 
                 Frac 
                 43.22 g/L 
                 Step 1 
                 Step 2 
                 Total** 
               
               
                   Sr. No. 
                     Analyte 
                 Frac Water (D) 
                 Concentration (Step 1) (Y)* 
                 Water (Step 1) (Q) 
                 Treated Frac Water (Step 2) (U) 
                 
                   
                     
                       
                         = 
                         
                           
                             
                               Y 
                               - 
                               Q 
                             
                             Y 
                           
                           × 
                           100 
                         
                       
                     
                   
                 
                 
                   
                     
                       
                         = 
                         
                           
                             
                               Q 
                               - 
                               U 
                             
                             Q 
                           
                           × 
                           100 
                         
                       
                     
                   
                 
                 
                   
                     
                       
                         = 
                         
                           
                             
                               Y 
                               - 
                               U 
                             
                             Y 
                           
                           × 
                           100 
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.77 
                 — 
                 6.31 
                 8.26 
                 — 
                 — 
                 — 
               
               
                 2. 
                 Calcium 
                 13,800 
                 13,687 
                 13,000 
                 43 
                 5 
                 100 
                 100 
               
               
                 3. 
                 Iron 
                 103 
                 102 
                 5 
                 1 
                 95 
                 80 
                 99 
               
               
                 4. 
                 Barium 
                 451 
                 447 
                 430 
                 5.2 
                 4 
                 99 
                 99 
               
               
                 5. 
                 Strontium 
                 2,690 
                 2,668 
                 2,500 
                 99 
                 6 
                 96 
                 96 
               
               
                 6. 
                 Hardness  
                 38,231  
                 37,917  
                 36,313 
                 2,445 
                 4 
                 93 
                 94 
               
               
                 7. 
                 Sulfate 
                 109 
                 108 
                 21 
                 21 
                 81 
                 0 
                 81 
               
               
                 8. 
                 Zinc 
                 0.5700  
                 0.5653 
                 19 
                 0.2 
                 −3,261 
                 99 
                 65 
               
               
                 9. 
                 TSS 
                 1,020 
                 1,012 
                 60 
                 102 
                 94 
                 −70 
                 90 
               
               
                 10. 
                 Potassium 
                 3,440 
                 3,412 
                 2,200 
                 2,100 
                 36 
                 5 
                 38 
               
               
                 11. 
                 Magnesium  
                 910 
                 903 
                 930 
                 570 
                 −3 
                 39 
                 37 
               
               
                 12. 
                 Chloride  
                 145,000 
                 143,810 
                 89,000 
                 110,000 
                 38 
                 −24 
                 24 
               
               
                 13. 
                 Lithium 
                 100 
                 99 
                 94 
                 83 
                 5 
                 12 
                 16 
               
               
                 14. 
                 TDS 
                 205,000  
                 203,318 
                 150,000 
                 210,000 
                 26 
                 −40 
                 −3 
               
               
                 15. 
                 Sodium 
                 46,900  
                 46,515 
                 48,000 
                 60,000 
                 −3 
                 −25 
                 −29 
               
               
                   
               
               
                 *In the 1 st  processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 2 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=1 hour 
     3. Catalytic Metal Sludge (S)=78.5 gm 
     4. Treated Frac Water (Q)=1,452 mL 
     Second (2 nd ) Processing Step—Metal Precipitation by Carbonate (e.g., Na 2 CO 3 ) Followed by Filtration: 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=570 mL 
     2. Reaction time (τ)=38 min (0.63 hour) 
     3. Filtered Sludge (R)=74 gm 
     4. Treated Frac Water (U)=520 mL 
     Note: In this unit operation, 570 mL was used from Treated Frac Water (Q). The remaining water was used for water testing. 
     See Table II below for the Experiment Trial 2 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                 1 st  Processing Step 
                 2 nd  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 25 g/L 
                 Na 2 CO 3  to Frac 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                 Water ratio =  
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 7 g/g 
                 43.22 g/L 
                   
               
             
          
           
               
                   
                   
                 Untreated 
                 Diluted 
                 Treated 
                 Treated 
                 Analyte Removal (%) 
               
             
          
           
               
                   Sr. No. 
                     Analyte 
                 Frac Water (D) 
                 Concentration (Step 1) (Y) * 
                 Frac Water (Step 1) (Q) 
                 Frac Water (Step 2) (U) 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   1 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   2 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Q 
                                     - 
                                     U 
                                   
                                   Q 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Total 
                                   ** 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     U 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 6.19 
                 — 
                 6.88 
                 9.77 
                 — 
                 — 
                 — 
               
               
                 2. 
                 Calcium 
                 6,900 
                 6,843 
                 6,700 
                 32 
                 2 
                 100 
                 100 
               
               
                 3. 
                 Iron 
                 22 
                 22 
                 2 
                 1.2 
                 91 
                 40 
                 95 
               
               
                 4. 
                 Barium 
                 740 
                 734 
                 690 
                 1.3 
                 6 
                 100 
                 100 
               
               
                 5. 
                 Strontium 
                 1,500 
                 1,488 
                 1400 
                 15 
                 6 
                 99 
                 99 
               
               
                 6. 
                 Hardness 
                 19,915 
                 19,752 
                 19,374 
                 941 
                 2 
                 95 
                 95 
               
               
                 7. 
                 Sulfate 
                 360 
                 357 
                 240 
                 250 
                 33 
                 −4 
                 30 
               
               
                 8. 
                 Zinc 
                 0.25 
                 0.25 
                 6 
                 0.25 
                 −2,320 
                 96 
                 −1 
               
               
                 9. 
                 TSS 
                 140 
                 139 
                 21 
                 19 
                 85 
                 10 
                 86 
               
               
                 10.  
                 Potassium 
                 690 
                 684 
                 670 
                 600 
                 2 
                 10 
                 12 
               
               
                 11. 
                 Magnesium 
                 650 
                 645 
                 640 
                 210 
                 1 
                 67 
                 67 
               
               
                 12.  
                 Chloride 
                 59,000 
                 58,516 
                 58,000 
                 56,000 
                 1 
                 3 
                 4 
               
               
                 13.  
                 Lithium 
                 49 
                 49 
                 47 
                 42 
                 3 
                 11 
                 14 
               
               
                 14.  
                 TDS 
                 110,000 
                 109,097 
                 75,000 
                 120,000 
                 31 
                 −60 
                 −10 
               
               
                 15.  
                 Sodium 
                 26,000 
                 25,787 
                 26,000 
                 39,000 
                 −1 
                 −50 
                 −51 
               
               
                   
               
               
                 * In the 1 st  processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 3 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration 
     1. Volume of Frac Water (D)=5 gallons (18.927 gallons) 
     2. Reaction time (τ)=1 hour 
     Second (2 nd ) Processing Step—Metal Precipitation by Carbonate (e.g., Na 2 CO 3 ) Followed by Filtration: 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=1.056 gallons (4 liter) 
     2. Reaction time (τ)=30 min (0.5 hour) 
     Note: In this first unit process, only 1.056 gallons (4 liter) of frac water was filtered for the 2 nd  processing step. 
     See Table III below for the Experiment Trial 3 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                   
                 2 nd  Processing 
                   
               
               
                   
                   
                 1 st  Processing Step 
                 Step Na 2 CO 3    
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 25 g/L 
                 to Frac Water 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                 ratio = 43.22 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 7 g/g 
                 g/L 
                   
               
             
          
           
               
                   
                   
                   
                 Diluted 
                 Treated 
                 Treated 
                 Analyte Removal (%) 
               
             
          
           
               
                   Sr. No. 
                     Analyte 
                 Untreated Frac Water (D) 
                 Concentration (Step 1) (Y) * 
                 Frac Water (Step 1) (Q) 
                 Frac Water (Step 2) (U) 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   1 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   2 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Q 
                                     - 
                                     U 
                                   
                                   Q 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Total 
                                   ** 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     U 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 5.76 
                 — 
                 6.34 
                 7.68 
                 — 
                 — 
                 — 
               
               
                 2. 
                 Calcium 
                 13,000 
                 12,893 
                 12,000 
                 230 
                 7 
                 98 
                 98 
               
               
                 3. 
                 Iron 
                 85 
                 84 
                 0.19 
                 0.12 
                 100 
                 37 
                 100 
               
               
                 4. 
                 Barium 
                 2,700 
                 2,678 
                 2,500 
                 180 
                 7 
                 93 
                 93 
               
               
                 5. 
                 Strontium 
                 2,600 
                 2,579 
                 2,500 
                 540 
                 3 
                 78 
                 79 
               
               
                 6. 
                 Hardness 
                 37,420 
                 37,113 
                 34,920 
                 3,732 
                 6 
                 89 
                 90 
               
               
                 7. 
                 Sulfate 
                 220 
                 218 
                 490 
                 580 
                 −125 
                 −18 
                 −166 
               
               
                 8. 
                 Zinc 
                 0.067 
                 0.07 
                 16 
                 0.034 
                 −23,978 
                 100 
                 49 
               
               
                 9. 
                 TSS 
                 610 
                 605 
                 56 
                 71 
                 91 
                 −27 
                 88 
               
               
                 10. 
                 Potassium 
                 420 
                 417 
                 400 
                 400 
                 4 
                 0 
                 4 
               
               
                 11. 
                 Magnesium 
                 1,200 
                 1,190 
                 1,200 
                 770 
                 −1 
                 36 
                 35 
               
               
                 12. 
                 Chloride 
                 99,000 
                 98,187 
                 89,000 
                 89,000 
                 9 
                 0 
                 9 
               
               
                 13. 
                 Lithium 
                 110 
                 109 
                 100 
                 88 
                 8 
                 12 
                 19 
               
               
                 14. 
                 TDS 
                 180,000 
                 178,522 
                 160,000 
                 170,000 
                 10 
                 −6 
                 5 
               
               
                 15. 
                 Sodium 
                 39,000 
                 38,680 
                 36,000 
                 50,000 
                 7 
                 −39 
                 −29 
               
               
                   
               
               
                 * In the 1 st  processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 4 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=10 gallons (37.854 liter) 
     2. Reaction time (τ)=1 hour 
     Second (2 nd ) Processing Step—Metal Precipitation by Carbonate (e.g., Na 2 CO 3 ) Followed by Filtration 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=5 gallons (18.927 liter) 
     2. Reaction time (τ)=30 min (0.5 hour) 
     Note: In this first unit process, only 5 gallons (18.927 liter) of frac water was filtered for the 2 nd  processing step. 
     See Table IV below for the Experiment Trial 4 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                 1 st  Processing Step 
                   
                   
               
               
                   
                   
                 Catalyst to Frac Water 
                   
                   
               
               
                   
                   
                 ratio = 25 g/L 
                   
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                 2 nd  Processing Step 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2   
                 Na 2 CO 3  to Frac Water 
                   
               
               
                   
                   
                 (100%) ratio = 7 g/g 
                 ratio = 43.22 g/L 
                   
               
             
          
           
               
                   
                   
                 Untreated 
                 Diluted 
                 Treated 
                 Treated 
                 Analyte Removal (%) 
               
             
          
           
               
                   Sr. No. 
                     Analyte 
                 Frac Water (D) 
                 Concentration (Step 1) (Y) * 
                 Frac Water (Step 1) (Q) 
                 Frac Water (Step 2) (U) 
                 
                   
                     
                       
                           
                         
                             
                           
                             
                               
                                 
                                   
                                     Step 
                                     ⁢ 
                                     
                                         
                                     
                                     ⁢ 
                                     1 
                                   
                                   = 
                                 
                               
                             
                             
                               
                                 
                                   
                                     
                                       Y 
                                       - 
                                       Q 
                                     
                                     Y 
                                   
                                   × 
                                   100 
                                 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   2 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Q 
                                     - 
                                     U 
                                   
                                   Q 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Total 
                                   ** 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     U 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 5.88 
                 — 
                 6.32 
                 8.5 
                 — 
                 — 
                   
               
               
                 2. 
                 Calcium 
                 13,000 
                 12,893 
                 13,000 
                 83 
                 −1 
                 99 
                 99 
               
               
                 3. 
                 Iron 
                 85 
                 84 
                 0.24 
                 0.12 
                 100 
                 50 
                 100 
               
               
                 4. 
                 Barium 
                 2,700 
                 2,678 
                 2,100 
                 48 
                 22 
                 98 
                 98 
               
               
                 5. 
                 Strontium 
                 2,600 
                 2,579 
                 2,900 
                 240 
                 −12 
                 92 
                 91 
               
               
                 6. 
                 Hardness 
                 37,420 
                 37,113 
                 37,830 
                 2,995 
                 −2 
                 92 
                 92 
               
               
                 7. 
                 Sulfate 
                 220 
                 218 
                 360 
                 330 
                 −65 
                 8 
                 −51 
               
               
                 8. 
                 Zinc 
                 0.067 
                 0.07 
                 27 
                 0.02 
                 −40,532 
                 100 
                 70 
               
               
                 9. 
                 TSS 
                 610 
                 605 
                 33 
                 23 
                 95 
                 30 
                 96 
               
               
                 10. 
                 Potassium 
                 420 
                 417 
                 510 
                 480 
                 −22 
                 6 
                 −15 
               
               
                 11. 
                 Magnesium 
                 1,200 
                 1,190 
                 1,300 
                 670 
                 −9 
                 48 
                 44 
               
               
                 12. 
                 Chloride 
                 99,000 
                 98,187 
                 98,000 
                 93,000 
                 0 
                 5 
                 5 
               
               
                 13. 
                 Lithium 
                 110 
                 109 
                 110 
                 96 
                 −1 
                 13 
                 12 
               
               
                 14. 
                 TDS 
                 180,000 
                 178,522 
                 150,000 
                 140,000 
                 16 
                 7 
                 22 
               
               
                 15. 
                 Sodium 
                 39,000 
                 38,680 
                 39,000 
                 56,000 
                 −1 
                 −44 
                 −45 
               
               
                   
               
               
                 * In the 1 st  processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
             
          
         
       
     
     Now turning to  FIG. 2  that illustrates a baseline case of the second processing step of the embodiment shown in  FIG. 1 . Each of these processing steps consists of two (2) unit operations. 
     In this process, the first unit operation is metal precipitation by Carbonate(s)  110 . In this unit operation, the wastewater D (e.g., frac water) is added to the Metal Precipitation Tank/Reactor  110  from the wastewater storage tank/impoundment  40  followed by adding measured amounts of Carbonate(s) (e.g., Na 2 CO 3 ) (H) (Na 2 CO 3  to Frac Water ratio=1-100 g/L). After that, the mixture is stirred continuously. Carbonate(s) addition precipitate divalent metals such as Barium, Strontium, Calcium, Magnesium and other metals as insoluble metals salts (i.e., barium carbonate, strontium carbonate, calcium carbonate, magnesium carbonate, etc.). The typical reaction time for this unit process is thirty (30) minutes to one (1) hour. After the metal precipitation unit operation is complete, the carbonate metal slurry P is transferred to physical separation units such as a Filtration unit  60 . 
     In this process, the second unit operation is filtration  60 . In this unit operation, the carbonate metal slurry P from the metal precipitation tank/reactor  110  is pumped or gravity fed to the filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These filtration units separate treated frac water Q from the carbonate metal slurry P and produce a filtered sludge R. The water recovery for this unit operation is 85 to 95%. The filtered sludge R can then be disposed in a secured landfill. The treated frac water Q contains lower amounts of Iron (Fe), Calcium (Ca), Potassium (K), and Total Suspended Solids (TSS) than the wastewater, such as frac water. 
     Experimental trial of this baseline process 1 for the present invention of  FIG. 1  is presented in Table V below. 
     1. Volume of Frac Water (D)=1,000 mL 
     2. Reaction time (τ)=30 min (0.5 hour) 
     3. Filtered Sludge (R)=46 gm 
     4. Treated Frac Water (Q)=964 mL 
     See Table V below for the Experiment Trial 5 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration  
                   
               
               
                   
                   
                 (mg/L or ppm) 
                   
               
               
                   
                   
                 Na 2 CO 3  to Frac 
                   
               
               
                   
                   
                 Water ratio = 25.05 g/L 
                   
               
             
          
           
               
                       Sr. No. 
                         Analyte 
                     Untreated Frac Water (D) 
                     Treated Frac Water (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     D 
                                     - 
                                     Q 
                                   
                                   D 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.44 
                 6.07 
                 — 
               
               
                 2. 
                 Calcium 
                 13,800 
                 7,400 
                 46 
               
               
                 3. 
                 Iron 
                 103 
                 1.2 
                 99 
               
               
                 4. 
                 Barium 
                 451 
                 370 
                 18 
               
               
                 5. 
                 Strontium 
                 2,690 
                 2,500 
                 7 
               
               
                 6. 
                 Hardness 
                 38,231 
                 21,944 
                 43 
               
               
                 7. 
                 Sulfate 
                 109 
                 440 
                 −304 
               
               
                 8. 
                 Zinc 
                 0.575 
                 0.25 
                 57 
               
               
                 9. 
                 TSS 
                 1,020 
                 36 
                 96 
               
               
                 10. 
                 Potassium 
                 3,440 
                 2,400 
                 30 
               
               
                 11. 
                 Magnesium 
                 910 
                 840 
                 8 
               
               
                 12. 
                 Chloride 
                 145,000 
                 130,000 
                 10 
               
               
                 13. 
                 Lithium 
                 100 
                 100 
                 0 
               
               
                 14. 
                 TDS 
                 205,000 
                 240,000 
                 −17 
               
               
                 15. 
                 Sodium 
                 46,900 
                 66,000 
                 −41 
               
               
                   
               
             
          
         
       
     
     Now turning to  FIG. 3  illustrating a baseline case of Catalytic Adsorption followed by Magnetic Separation or Filtration, which is the second processing illustration of another embodiment of the present invention shown in  FIG. 4 . 
       FIG. 3  shows one (1) processing step for treating frac water. In this process, the first unit operation is catalytic adsorption  140 . In this unit operation, the wastewater D (e.g., frac water) is added to a Catalytic Adsorption Tank/Reactor  140  from the wastewater storage tank/impoundment  40  followed by adding measured amounts of BOF Slag (Catalyst) C (Catalyst to Frac Water ratio=1-300 g/L). After that, the mixture is stirred continuously. The dried BOF Slag (Catalyst) (C) addition removes metals such as Iron, and Barium from the frac water by adsorption phenomenon. The typical reaction time for this unit process is thirty (30) minutes to three (3) hours. After the catalytic adsorption unit operation  140  is complete, the catalytic metal slurry T is transferred to physical separation units such as a Magnetic Separation Unit  80  or Filtration unit  60 . 
     In the second processing step, the second unit operation is physical separation unit such as magnetic separation  80  or filtration  60 . In this unit operation, the catalytic metal slurry T from catalytic adsorption tank/reactor  140  is pumped or gravity fed to the magnetic separation unit  80  or filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These physical separation units separate the treated frac water Q from the catalytic metal slurry T and produce a catalytic metal sludge S. The water recovery for this unit operation is 80 to 90%. This catalytic metal sludge S can then be either disposed in a secured landfill W or recycled in a catalyst regeneration process  90 . The treated frac water Q contains lower amounts of Iron (Fe), Potassium (K), and Total Suspended Solids (TSS) than the wastewater, such as frac water. 
     Experimental trial of this baseline process 2 (Catalytic Adsorption followed by Magnetic Separation or Filtration) for this embodiment of the present invention is presented in the Table VI below: 
     1. Volume of Frac Water (D)=1,000 mL 
     2. Weight of BOF Slag (Catalyst) (C)=250 gm 
     3. Reaction time (τ)=1 hour 
     4. Catalytic Metal Sludge (S)=405 gm 
     5. Treated Frac Water (Q)=834 mL 
     See Table VI below for the Experiment Trial 6 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE VI 
               
             
             
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                         Untreated Frac Water (D) 
                         Treated Frac Water (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     D 
                                     - 
                                     Q 
                                   
                                   D 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.54 
                 7.73 
                 — 
               
               
                 2. 
                 Calcium 
                 13,800 
                 15,000 
                 −9 
               
               
                 3. 
                 Iron 
                 103 
                 1.2 
                 99 
               
               
                 4. 
                 Barium 
                 451 
                 450 
                 0.22 
               
               
                 5. 
                 Strontium 
                 2,690 
                 2,800 
                 −4 
               
               
                 6. 
                 Hardness 
                 38,231 
                 41,600 
                 −9 
               
               
                 7. 
                 Sulfate 
                 109 
                 420 
                 −285 
               
               
                 8. 
                 Zinc 
                 0.575 
                 4.9 
                 −752 
               
               
                 9. 
                 TSS 
                 1,020 
                 55 
                 95 
               
               
                 10. 
                 Potassium 
                 3,440 
                 2,400 
                 30 
               
               
                 11. 
                 Magnesium 
                 910 
                 1,000 
                 −10 
               
               
                 12. 
                 Chloride 
                 145,000 
                 130,000 
                 10 
               
               
                 13. 
                 Lithium 
                 100 
                 100 
                 0 
               
               
                 14. 
                 TDS 
                 205,000 
                 25,0000 
                 −22 
               
               
                 15. 
                 Sodium 
                 46,900 
                 54,000 
                 −15 
               
               
                   
               
             
          
         
       
     
       FIG. 4  is an illustration of another embodiment of the present invention including a three-step process for recovering rich barium/iron sludge, wherein the first processing step is Catalytic Oxidation followed by Magnetic Separation or Filtration, second processing step is Desorption of the Barium and soluble Fe, and third processing step is Precipitation of Barium and soluble Fe as carbonates. 
       FIG. 4  shows three (3) processing steps for recovering rich barium/iron sludge by treating frac water. Each of these processing steps consists of two (2) unit operations. In the first processing step, the first unit operation is catalytic oxidation  100 . In this unit operation, the wastewater D (e.g., frac water) is added to the Catalytic Oxidation Tank/Reactor  100  from the wastewater storage tank/impoundment  40  followed by adding measured amounts of BOF Slag (Catalyst) (C) (Catalyst to Frac Water ratio=1-300 g/L), and Hydrogen Peroxide (G) (to produce a 0.1-2.0 M solution). The Catalytic Oxidation unit operation ( 100 ) produces reactions because of the reaction between Iron (Fe) particles in the BOF Slag (Catalyst) C and Hydrogen Peroxide G. This reaction generates the hydroxyl free radicals (OH.), which is capable of removing/oxidizing organics, metals, and possibly radionuclides. One embodiment of the present invention removal mechanism for this unit operation is a combination of chemical and electrolytic mechanisms: catalytic oxidation, colloidal co-precipitation and metals adsorption onto the catalyst (BOF Slag particles) surface. The Catalytic Metal Slurry T is then transferred to physical separation processes such as magnetic separation unit  80  or filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). The typical reaction time for this unit operation is thirty (30) minutes to three (3) hours. 
     In the first processing step, the second unit operation is physical separation unit such as magnetic separation  80  or filtration  60 . In this unit operation, the catalytic metal slurry T from the catalytic oxidation tank/reactor  100  is pumped or gravity fed to the magnetic separation unit  80  or filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These physical separation units separate the treated frac water Q from the catalytic metal slurry T and produce a catalytic metal sludge S. The water recovery for this unit operation is 85 to 95%. This catalytic metal sludge S can then be either disposed in a secured landfill W or recycled in a catalyst regeneration process  90  (see  FIG. 3 ). The treated frac water Q contains lower amounts of Iron (Fe), Barium (Ba), Sulfates (SO 4 ) and Total Suspended Solids (TSS) than the wastewater, such as frac water. 
     In the second processing step, the first unit operation is metal desorption process  160 . In this unit operation, the catalytic metal sludge S is added to Metal Desorption Process  160  followed by adding measured amounts of De-ionized DI water (L) (DI Water (l) to Catalyst Metal Sludge S=0.25-2 mL/g). After that, the mixture is stirred continuously. DI water desorbs barium and iron from the catalytic metal sludge S. The typical reaction time for this unit operation is thirty (30) minutes to one (1) hour. After the metal desorption process  160  is complete, the Barium/Iron rich slurry T 1  is transferred to physical separation units such as Magnetic separation  80  or Filtration unit  60 . 
     In the second processing step, the second unit operation is physical separation unit such as magnetic separation  80  or filtration  60 . In this unit operation, the Barium/Iron rich slurry T 1  from metal desorption tank/reactor  160  is pumped or gravity fed to the magnetic separation unit  80  or filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These physical separation units separate the wet BOF Slag for reuse or disposal (A) from the Barium/Iron rich slurry T 1  and produce filtered water containing rich Barium/Iron sludge a. 
     In the third processing step, the first unit operation is metal precipitation by Carbonate(s)  110 . In this unit operation, the wastewater (e.g., frac water) D is added to the Metal Precipitation Tank/Reactor  110  from the wastewater storage tank/impoundment  40  followed by adding measured amounts of Carbonate(s) (e.g., Na 2 CO 3 ) H (Na 2 CO 3  to Frac Water ratio=1-25 g/L). After that, the mixture is stirred continuously. The Carbonate(s) addition precipitates out barium and iron as insoluble barium carbonate and iron carbonate, respectively. The typical reaction time for this unit process is thirty (30) minutes to one (1) hour. After the metal precipitation unit operation is complete, the carbonate metal slurry P is transferred to physical separation units such as a Filtration unit  60 . 
     In the third processing step, the second unit operation is filtration  60 . In this unit operation, the carbonate metal slurry P from the metal precipitation tank/reactor  110  is pumped or gravity fed to the filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These filtration units separate a rich barium/iron (Ba/Fe) sludge Z from the carbonate metal slurry P and produce a filtered water for further treatment β. A rich barium/iron (Ba/Fe) sludge z can be then send to barium refining facility for barium reclamation. 
     An embodiment of this present invention includes a composition for the first (1 st ) Processing Step—Catalytic Oxidation followed by Magnetic Separation or Filtration to include Catalyst to Frac Water ratio=1-300 g/L, H 2 O 2  Concentration=0.1-2 M solution, and Catalyst to H 2 O 2  (100%) ratio=0.25-7 g/g; the second (2 nd ) Processing Step—Desorption of the Barium and Soluble Fe to include adding measured amounts of De-ionized DI water (L) (DI Water (l) to Catalyst Metal Sludge S=0.25-2 mL/g; and the third (3 rd ) Processing Step—Precipitation of Barium and Soluble Fe by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration to include Na 2 CO 3  to Frac Water ratio=1-100 g/L. 
     Another embodiment of this present invention includes a composition for the first (1 st ) Processing Step—Catalytic Oxidation followed by Magnetic Separation or Filtration to include Catalyst to Frac Water ratio=240-270 g/L, H 2 O 2  Concentration=1-1.5 M solution, and Catalyst to H 2 O 2  (100%) ratio=5.3-7.5 g/g; the second (2 nd ) Processing Step—Desorption of the Barium and Soluble Fe to include adding measured amounts of De-ionized DI water (L) (DI Water (l) to Catalyst Metal Sludge S=0.25-2 mL/g; and the third (3 rd ) Processing Step—Precipitation of Barium and Soluble Fe by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration to include Na 2 CO 3  to Frac Water ratio=40-45 g/L. 
     Yet another embodiment of this present invention (see Tables VII and VIII) includes a composition for the first (1 st ) Processing Step—Catalytic Oxidation followed by Magnetic Separation or Filtration to include Catalyst to Frac Water ratio=250 g/L, H 2 O 2  Concentration=1.35 M solution, and Catalyst to H 2 O 2  (100%) ratio=3 g/g; the second (2 nd  Processing Step—Desorption of the Barium and Soluble Fe to include adding measured amounts of De-ionized DI water (L) (DI Water (l) to Catalyst Metal Sludge S=0.25-2 mL/g; and the third (3 rd ) Processing Step—Precipitation of Barium and Soluble Fe by Carbonate(s) (e.g., Na 2 CO 3 ) followed by Filtration to include Na 2 CO 3  to Frac Water ratio=43.22 g/L. 
     Experimental trials of this embodiment of the present invention (three-step unit process) are conducted in the experimental trials 7, 8, 9, 10, 11 and 12 with results presented in Tables VII, VIII, IX, X, XII, and XII, respectively. 
     Experimental Trial 7 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=480 mL 
     2. Reaction time (τ)=19.45 hours 
     3. Catalytic Metal Sludge (S)=285 gm 
     4. Treated Frac Water (Q)=710 mL 
     See Table VII below for the Experiment Trial 7 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
               
                   
                   
                 1 st  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 250 g/L 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 1.35M solution 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 3 g/g 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                       Untreated Frac Water (D) 
                     Diluted Concentration (Y) * 
                       Treated Frac Water (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 4.3 
                 — 
                 7.5 
                 — 
               
               
                 2. 
                 Calcium 
                 12,000 
                 6,546 
                 7,720 
                 −18 
               
               
                 3. 
                 Iron 
                 85 
                 47 
                 1.3 
                 97 
               
               
                 4. 
                 Barium 
                 447 
                 244 
                 97 
                 60 
               
               
                 5. 
                 Strontium 
                 2,440 
                 1,331 
                 1,470 
                 −10 
               
               
                 6. 
                 Hardness 
                 33,846 
                 18,463 
                 22,719 
                 −23 
               
               
                 7. 
                 Sulfate 
                 100 
                 55 
                 49 
                 10 
               
               
                 8. 
                 Zinc 
                 0.62 
                 0.34 
                 7.23 
                 −2,038 
               
               
                 9. 
                 Magnesium 
                 938 
                 512 
                 834 
                 −63 
               
               
                 10. 
                 Chloride 
                 111,000 
                 60,551 
                 60,100 
                 1 
               
               
                 11. 
                 TDS 
                 184,000 
                 100,372 
                 110,000 
                 −10 
               
               
                 12. 
                 Sodium 
                 40,600 
                 22,147 
                 23,200 
                 −5 
               
               
                 13 
                 TOC 
                 21 
                 11 
                 14 
                 −22 
               
               
                   
               
               
                 * In the processing step, adding H 2 O 2  resulted in a 45.45% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 8 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=580 mL 
     2. Reaction time (τ)=23 hours 
     3. Catalytic Metal Sludge (S)=280 gm 
     4. Treated Frac Water (Q)=924 mL 
     See Table VIII below for the Experiment Trial 8 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
               
                   
                   
                 1 st  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 250 g/L 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 1.35M solution 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 3 g/g 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                       Untreated Frac Water (D) 
                     Diluted Concentration (Y) * 
                       Treated Frac Water (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 4.6 
                 — 
                 7.45 
                 — 
               
               
                 2. 
                 Calcium 
                 12,000 
                 6,546 
                 6,290 
                 4 
               
               
                 3. 
                 Iron 
                 85 
                 46 
                 0.86 
                 98 
               
               
                 4. 
                 Barium 
                 447 
                 244 
                 76 
                 69 
               
               
                 5. 
                 Strontium 
                 2,440 
                 1,331 
                 1,260 
                 5 
               
               
                 6. 
                 Hardness 
                 33,846 
                 18,463 
                 18,616 
                 −1 
               
               
                 7. 
                 Sulfate 
                 100 
                 55 
                 40.5 
                 26 
               
               
                 8. 
                 Zinc 
                 0.62 
                 0.34 
                 4.82 
                 −1,325 
               
               
                 9. 
                 Magnesium 
                 938 
                 512 
                 705 
                 −38 
               
               
                 10. 
                 Chloride 
                 111,000 
                 60,551 
                 57,800 
                 5 
               
               
                 11. 
                 TDS 
                 184,000 
                 100,372 
                 102,500 
                 −2 
               
               
                 12. 
                 Sodium 
                 40,600 
                 22,147 
                 22,000 
                 1 
               
               
                   
               
               
                 * In the processing step, adding H 2 O 2  resulted in a 45.45% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 9 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=1,080 mL 
     2. Reaction time (τ)=3 hours 
     3. Catalytic Metal Sludge (S)=750 gm 
     4. Treated Frac Water (Q)=1,010 mL 
     See Table IX below for the Experiment Trial 9 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
               
                   
                   
                 1 st  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 500 g/L 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 1.54M solution 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 8.41 g/g 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                       Untreated Frac Water (D) 
                     Diluted Concentration (Y) * 
                       Treated Frac Water (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 4.3 
                 — 
                 8.50 
                 — 
               
               
                 2. 
                 Calcium 
                 12,000 
                 10,550 
                 11,600 
                 −10 
               
               
                 3. 
                 Iron 
                 85 
                 75 
                 1.86 
                 98 
               
               
                 4. 
                 Barium 
                 447 
                 393 
                 214 
                 46 
               
               
                 5. 
                 Strontium 
                 2,440 
                 2,145 
                 2,100 
                 2 
               
               
                 6. 
                 Hardness 
                 33,846 
                 29,757 
                 32,829 
                 −10 
               
               
                 7. 
                 Sulfate 
                 100 
                 88 
                 58.7 
                 33 
               
               
                 8. 
                 Zinc 
                 0.62 
                 0.55 
                 1.28 
                 −135 
               
               
                 9. 
                 Magnesium 
                 938 
                 825 
                 934 
                 −13 
               
               
                 10. 
                 Chloride 
                 111,000 
                 97,591 
                 98,700 
                 −1 
               
               
                 11. 
                 TDS 
                 184,000 
                 161,773 
                 200,700 
                 −24 
               
               
                 12. 
                 Sodium 
                 40,600 
                 35,696 
                 38,200 
                 −7 
               
               
                   
               
               
                 * In the processing step, adding H 2 O 2  resulted in a 12.08% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 10 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=1 hour 
     3. Catalytic Metal Sludge (S)=70 gm 
     4. Treated Frac Water (Q)=1,470 mL 
     See Table X below for the Experiment Trial 10 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE X 
               
             
             
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
               
                   
                   
                 1 st  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 25 g/L 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 7 g/g 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                       Untreated Frac Water (D) 
                     Diluted Concentration (Step 1) (Y) * 
                       Treated Frac Water (Step 1) Q 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.77 
                 — 
                 6.31 
                 — 
               
               
                 2. 
                 Calcium 
                 13,800 
                 13,687 
                 13,000 
                 5 
               
               
                 3. 
                 Iron 
                 103 
                 102 
                 5 
                 95 
               
               
                 4. 
                 Barium 
                 451 
                 447 
                 430 
                 4 
               
               
                 5. 
                 Strontium 
                 2,690 
                 2,668 
                 2,500 
                 6 
               
               
                 6. 
                 Hardness 
                 38,231 
                 37,917 
                 36,313 
                 4 
               
               
                 7. 
                 Sulfate 
                 109 
                 108 
                 21 
                 81 
               
               
                 8. 
                 Zinc 
                 0.5700 
                 0.5653 
                 19 
                 −3,261 
               
               
                 9. 
                 TSS 
                 1,020 
                 1,012 
                 60 
                 94 
               
               
                 10. 
                 Potassium 
                 3,440 
                 3,412 
                 2,200 
                 36 
               
               
                 11. 
                 Magnesium 
                 910 
                 903 
                 930 
                 −3 
               
               
                 12. 
                 Chloride 
                 145,000 
                 143,810 
                 89,000 
                 38 
               
               
                 13. 
                 Lithium 
                 100 
                 99 
                 94 
                 5 
               
               
                 14. 
                 TDS 
                 205,000 
                 203,318 
                 150,000 
                 26 
               
               
                 15. 
                 Sodium 
                 46,900 
                 46,515 
                 48,000 
                 −3 
               
               
                   
               
               
                 * In the processing step, adding H 2 O 2  resulted in a 0.82% dilution factor 
               
             
          
         
       
     
     Experimental Trial 11 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=1 hour 
     3. Catalytic Metal Sludge (S)=79 gm 
     4. Treated Frac Water (Q)=1,464 mL 
     See Table XI below for the Experiment Trial 11 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE XI 
               
             
             
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
               
                   
                   
                 1 st  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 25 g/L 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 7 g/g 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                       Untreated Frac Water (D) 
                     Diluted Concentration (Step 1) (Y) * 
                       Treated Frac Water (Step 1) (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.80 
                 — 
                 6.35 
                 — 
               
               
                 2. 
                 Calcium 
                 13,800 
                 13,687 
                 14,000 
                 −2 
               
               
                 3. 
                 Iron 
                 103 
                 102 
                 5 
                 95 
               
               
                 4. 
                 Barium 
                 451 
                 447 
                 450 
                 −1 
               
               
                 5. 
                 Strontium 
                 2,690 
                 2,668 
                 2,900 
                 −9 
               
               
                 6. 
                 Hardness 
                 38,231 
                 37,917 
                 36,313 
                 −3 
               
               
                 7. 
                 Sulfate 
                 109 
                 108 
                 21 
                 81 
               
               
                 8. 
                 Zinc 
                 0.5700 
                 0.5653 
                 23 
                 −3,933 
               
               
                 9. 
                 TSS 
                 1,020 
                 1,012 
                 69 
                 93 
               
               
                 10. 
                 Potassium 
                 3,440 
                 3,412 
                 2,400 
                 30 
               
               
                 11. 
                 Magnesium 
                 910 
                 903 
                 1,000 
                 −11 
               
               
                 12. 
                 Chloride 
                 145,000 
                 143,810 
                 120,000 
                 17 
               
               
                 13. 
                 Lithium 
                 100 
                 99 
                 100 
                 −1 
               
               
                 14. 
                 TDS 
                 205,000 
                 203,318 
                 160,000 
                 21 
               
               
                 15. 
                 Sodium 
                 46,900 
                 46,515 
                 51,000 
                 −10 
               
               
                   
               
               
                 * In the processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
             
          
         
       
     
     Experimental Trial 11 
     First (1 st ) Processing Step—Catalytic Oxidation Followed by Magnetic Separation or Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction Time (τ)=1 hour 
     3. Catalytic Metal Sludge (S)=78.5 gm 
     4. Treated Frac Water (Q)=1,452 mL 
     See Table XII below for the Experiment Trial 12 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE XII 
               
             
             
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
               
                   
                   
                 1 st  Processing Step 
                   
               
               
                   
                   
                 Catalyst to Frac Water ratio = 25 g/L 
                   
               
               
                   
                   
                 H 2 O 2  conc. = 0.1M solution 
                   
               
               
                   
                   
                 Catalyst to H 2 O 2  (100%) ratio = 7 g/g 
                   
               
             
          
           
               
                         Sr. No. 
                         Analyte 
                       Untreated Frac Water (D) 
                     Diluted Concentration (Step 1) (Y) * 
                       Treated Frac Water (Step 1) (Q) 
                 
                   
                     
                       
                           
                         
                           
                             
                               Analyte 
                             
                           
                           
                             
                               
                                 
                                   Removal 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   
                                     ( 
                                     % 
                                     ) 
                                   
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     Q 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 6.19 
                 — 
                 6.88 
                 — 
               
               
                 2. 
                 Calcium 
                 6,900 
                 6,843 
                 6,700 
                 2 
               
               
                 3. 
                 Iron 
                 22 
                 22 
                 2 
                 91 
               
               
                 4. 
                 Barium 
                 740 
                 734 
                 690 
                 6 
               
               
                 5. 
                 Strontium 
                 1,500 
                 1,488 
                 1,400 
                 6 
               
               
                 6. 
                 Hardness 
                 19,915 
                 19,752 
                 19,374 
                 2 
               
               
                 7. 
                 Sulfate 
                 360 
                 357 
                 240 
                 33 
               
               
                 8. 
                 Zinc 
                 0.25 
                 0.25 
                 5.9 
                 −2,280 
               
               
                 9. 
                 TSS 
                 140 
                 139 
                 21 
                 85 
               
               
                 10. 
                 Potassium 
                 690 
                 684 
                 670 
                 2 
               
               
                 11. 
                 Magnesium 
                 650 
                 645 
                 640 
                 1 
               
               
                 12. 
                 Chloride 
                 59,000 
                 58,516 
                 58,000 
                 1 
               
               
                 13. 
                 Lithium 
                 49 
                 49 
                 47 
                 3 
               
               
                 14. 
                 TDS 
                 110,000 
                 109,097 
                 75,000 
                 31 
               
               
                 15. 
                 Sodium 
                 26,000 
                 25,787 
                 26,000 
                 −1 
               
               
                   
               
               
                 * In the processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
             
          
         
       
     
     Now turning to  FIG. 5  that illustrates another embodiment of the present invention including a three-step process for recovering rich barium/iron sludge, wherein the first processing step is Metal Precipitation by Ferrous Sulfate followed by Filtration, second processing step is Catalytic Oxidation at high pH followed by Filtration, and third processing step is Sulfates Precipitation by Barium Carbonate followed by Filtration. 
     The intent of the process shown  FIG. 5  is to take advantage of the use of a sulfate salt, namely Ferrous Sulfate, to remove the divalent cations. The present invention does not use either calcium sulfate or sodium sulfate, since doing so would increase the calcium and sodium concentration to total dissolved solids (TDS). The challenge would be to find approach to removing the sulfates and iron. Since the soluble iron (Fe) could be high leaving the first processing step, the present invention uses catalytic oxidation at high Ph in the Second Processing Step to remove the soluble iron and enhance the removal of Magnesium without the addition of any coagulating, flocculating or softening agents. In addition, in this process the Second Processing Step can be replaced by the Catalytic Adsorption to achieve high Fe removal efficiency at lower Mg removal. The sulfate is removed in the Third Processing Step by the addition of Barium Carbonate. 
       FIG. 5  shows three (3) processing steps for treating frac water. Each of these processing steps consists of two (2) unit operations. In the first processing step, the first unit operation is metal precipitation by Ferrous Sulfate  50 . In this unit operation, the wastewater (e.g., frac water) D is added to the Metal Precipitation Tank/Reactor  50  from the wastewater storage tank/impoundment  40  followed by adding measured amounts of FeSO 4  (E) (FeSO 4  to Frac Water ratio=2-120 g/L). After that, the mixture is stirred continuously. Sulfates addition precipitate divalent metals such as Barium, Strontium, Calcium and other metals as insoluble metals salts (i.e., barium sulfate, strontium sulfate, calcium sulfate, etc.). The typical reaction time for this unit operation is thirty (30) minutes to one (1) hour. After the metal precipitation unit operation is complete, the metal sulfates slurry P 1  is transferred to physical separation units such as a Filtration unit  60 . 
     In the first processing step, the second unit operation is filtration  60 . In this unit operation, the metal sulfates slurry P 1  from the metal precipitation tank/reactor  50  is pumped or gravity fed to the filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These filtration units separate treated frac water Q from the metal sulfates slurry P 1  and produce a filtered sludge R. The water recovery for this unit operation is 85 to 95%. The filtered sludge R can then be disposed in a secured landfill. The treated frac water Q contains lower amounts of Barium (Ba), Calcium (Ca), Strontium (Sr), Total Suspended Solids (TSS), and Hardness (as CaCO 3 ) than the wastewater (such as frac water), but it does contain high amounts of Iron (Fe) and Sulfates (SO 4 ). 
     In the second processing step, the first unit operation is catalytic oxidation at high pH 70. In this unit operation, treated frac water from first processing step Q is added in the Catalytic Oxidation Tank/Reactor  70  followed by measured amounts of BOF Slag (Catalyst) C (Catalyst to Frac Water ratio=1-300 g/L), Hydrogen Peroxide G (to produce a 0.1-2.0 M solution), and Sodium Hydroxide (or other types of strong bases) F (NaOH to Frac Water ratio=5-100 g/L). After that, the mixture is stirred continuously. This Catalytic Oxidation at higher pH unit operation  70  produces a Fenton-like reaction because of the reaction between Iron (Fe) particles in the BOF Slag (Catalyst) C and Hydrogen Peroxide G. The Catalytic Oxidation at higher pH unit operation  70  produces a colloidal mix of insoluble metal hydroxides which readily adsorb onto the surface of BOF slag particles (ferrite particles). This colloidal phase (referred hereinafter as catalytic metal slurry (T)) is then transferred to physical separation processes such as filtration unit (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art) (60). The typical reaction time for this unit operation is thirty (30) minutes to three (3) hours. The proposed removal mechanism for this unit operation is a combination of chemical and electrolytic mechanisms: catalytic oxidation, colloidal co-precipitation and metals adsorption onto the catalyst (BOF Slag particles) surface. 
     In the second processing step, the second unit operation is filtration  60 . In this unit operation, the catalytic metal slurry T from the Catalytic Oxidation Tank/Reactor  70  is pumped or gravity fed to the filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art). These filtration units separate treated frac water U from the catalytic metal slurry T and produce a catalytic metal sludge S. The water recovery for this unit operation is 80 to 90%. This catalytic metal sludge S can then be either disposed in a secured landfill W or recycled in a catalyst regeneration process  90  (see  FIG. 3 ). The treated frac water U contains lower amounts of Iron (Fe), Barium (Ba), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Total Suspended Solids (TSS), and Hardness (as CaCO 3 ) than the wastewater, such as frac water. 
     In the third processing step, the first unit operation  130  is sulfates precipitation by Barium Carbonate (BaCO 3 ). In this unit operation, the treated frac water from second processing step U is added to a Sulfates Precipitation Tank/Reactor  130  followed by adding measured amounts of Barium Carbonate (BaCO 3 ) (J) (BaCO 3  to Frac Water ratio=2.5-10 g/L). After that, the mixture is stirred continuously. Barium Carbonate addition removes sulfates from the frac water as Barium Sulfate (BaSO 4 ). The typical reaction time for this unit operation is thirty (30) minutes to one (1) hour. After the metal precipitation unit operation is complete, the barium sulfate slurry P 2  is transferred to physical separation units such as a Filtration unit  60 . 
     In the third processing step, the second unit operation is filtration  60 . In this unit operation, the barium sulfate slurry P 2  from the metal precipitation tank/reactor  130  is pumped or gravity fed to the filtration unit  60  (e.g. Ultrafiltration, Microfiltration, Reverse Osmosis and other types of filters known in the art)  60 . These filtration units separate treated frac water V from the barium sulfate slurry P 2  and produce a filtered sludge R. The water recovery for this unit operation is 85 to 95%. The filtered sludge R can then be disposed in a secured landfill. The treated frac water U contains lower amounts of Iron (Fe), Barium (Ba), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Sulfate (SO 4 ), Total Suspended Solids (TSS), and Hardness (as CaCO 3 ) than the wastewater, such as frac water. 
     An embodiment of this present invention includes a composition for the first (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate followed by Filtration to include FeSO 4  to Frac Water ratio=2-120 g/L; the second (2 nd ) Processing Step—Catalytic Oxidation at high pH followed by Filtration to include Catalyst to Frac Water ratio=1-300 g/L, H 2 O 2  Concentration=0.1-2 M solution, Catalyst to H 2 O 2  (100%) ratio=0.25-7 g/g, and NaOH to Frac Water ratio=5-100 g/L; and the third (3 rd ) Processing Step—Sulfates Precipitation by Barium Carbonate followed by Filtration to include BaCO 3  to Frac Water ratio=2.5-10 g/L. 
     Another embodiment of this present invention includes a composition for the first (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate followed by Filtration to include FeSO 4  to Frac Water ratio=45-70 g/L; the second (2 nd ) Processing Step—Catalytic Oxidation at high pH followed by Filtration to include Catalyst to Frac Water ratio=240-270 g/L, H 2 O 2  Concentration=1-1.5 M Solution, Catalyst to H 2 O 2  (100%) ratio=5.3-7.5 g/g, and NaOH to Frac Water ratio=45-60 g/L; and the third (3 rd ) Processing Step—Sulfates Precipitation by Barium Carbonate followed by Filtration to include BaCO 3  to Frac Water ratio=3-3.5 g/L. 
     Yet another embodiment of this present invention (see Table XIV) includes a composition for the first (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate followed by Filtration to include FeSO 4  to Frac Water ratio=48.66 g/L; the second (2 nd ) Processing Step—Catalytic Oxidation at high pH followed by Filtration to include Catalyst to Frac Water ratio=250 g/L, H 2 O 2  Concentration=0.97 M Solution, Catalyst to H 2 O 2  (100%) ratio=7 g/g, and NaOH to Frac Water ratio=52.63 g/L; and the third (3 rd ) Processing Step—Sulfates Precipitation by Barium Carbonate followed by Filtration to include BaCO 3  to Frac Water ratio=3.3 g/L. 
     Experimental trials of this embodiment of the present invention (three-steps process) are conducted in the experimental trials 13, 14, 15, and 16 and presented in Tables XIII, XIV, XV, and XVI, respectively.’ 
     Experimental Trial 13 
     First (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate Followed by Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=30 min (0.5 hour) 
     3. Filtered Sludge (R)=290 gm 
     4. Treated Frac Water (Q)=1,300 mL 
     Second (2 nd ) Processing Step—Catalytic Oxidation at High pH Followed by Filtration: 
     1. Vol. of Treated Frac Water (Q) from 1 st  process. step=570 mL 
     2. Reaction time (τ)=50 min (0.83 hour) 
     3. Catalytic Metal Sludge (S)=220 gm 
     4. Treated Frac Water (U)=510 mL 
     Note: In this unit operation, 570 mL was used from Treated Frac Water Q. The remaining water was used for water testing. 
     See Table XIII below for the Experiment Trial 13 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                   
                 2 nd  Processing Step 
                   
               
               
                   
                   
                   
                 Catalyst to Frac Water ratio = 250 g/L 
                   
               
               
                   
                   
                   
                 H 2 O 2  conc. = 0.97M solution 
                   
               
               
                   
                   
                   
                 Catalyst to H 2 O 2   
                   
               
               
                   
                   
                 1 st  Processing Step 
                 (100%) ratio =7 g/g 
                   
               
               
                   
                   
                 FeSO 4  to Frac  
                 NaOH to Frac Water ratio = 52.63 g/L 
                   
               
             
          
           
               
                   
                   
                 Water ratio = 66.62 g/L 
                   
                 Treated 
                 Analyte Removal (%) 
               
             
          
           
               
                     Sr. No. 
                       Analyte 
                   Untreated Frac Water (D) 
                   Treated Frac Water (Step 2) (Q) 
                 Diluted Concentration (Step 1) (Y) * 
                 Frac Water (Step 2) (U) 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   1 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     D 
                                     - 
                                     Q 
                                   
                                   D 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Step 
                                   ⁢ 
                                   
                                       
                                   
                                   ⁢ 
                                   2 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     Y 
                                     - 
                                     U 
                                   
                                   Y 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
                 
                   
                     
                       
                           
                         
                           
                             
                               
                                 
                                   Total 
                                   ** 
                                 
                                 = 
                               
                             
                           
                           
                             
                               
                                 
                                   
                                     D 
                                     - 
                                     U 
                                   
                                   U 
                                 
                                 × 
                                 100 
                               
                             
                           
                         
                       
                     
                   
                 
               
               
                   
               
             
          
           
               
                 1. 
                 pH 
                 3.84 
                 1.98 
                 — 
                 11.84 
                 — 
                 — 
                 — 
               
               
                 2. 
                 Calcium 
                 13,800 
                 2,760 
                 2,549 
                 7 
                 80 
                 100 
                 100 
               
               
                 3. 
                 Iron 
                 103 
                 18,400 
                 16,994 
                 0.25 
                 −17,764 
                 100 
                 100 
               
               
                 4. 
                 Barium 
                 451 
                 0.013 
                 0.012 
                 0.018 
                 100 
                 −50 
                 100 
               
               
                 5. 
                 Strontium 
                 2,690 
                 732 
                 676 
                 7 
                 73 
                 99 
                 100 
               
               
                 6. 
                 Hardness 
                 38,231 
                 10,303 
                 9,515 
                 18 
                 73 
                 100 
                 100 
               
               
                 7. 
                 Sulfate 
                 109 
                 3,870 
                 3,574 
                 3,740 
                 −3,450 
                 −5 
                 −3,593 
               
               
                 8. 
                 Zinc 
                 0.57 
                 2.60 
                 2.40 
                 6.5 
                 −356 
                 −171 
                 −1,128 
               
               
                 9. 
                 TSS 
                 1,020 
                 130 
                 120 
                 75 
                 87 
                 38 
                 92 
               
               
                 10. 
                 Potassium 
                 3,440 
                 3,040 
                 2,808 
                 3,720 
                 12 
                 −32 
                 −16 
               
               
                 11. 
                 Magnesium 
                 910 
                 830 
                 767 
                 0.21 
                 9 
                 100 
                 100 
               
               
                 12. 
                 Chloride 
                 145,000 
                 105,000 
                 96,974 
                 100,000 
                 28 
                 −3 
                 26 
               
               
                 13. 
                 Lithium 
                 100 
                 95 
                 88 
                 71 
                 5 
                 19 
                 24 
               
               
                 14. 
                 TDS 
                 205,000 
                 156,000 
                 144,075 
                 146,000 
                 24 
                 −1 
                 23 
               
               
                 15. 
                 Sodium 
                 46,900 
                 42,400 
                 39,159 
                 61,300 
                 10 
                 −57 
                 −41 
               
               
                   
               
               
                 * In the 2 nd  processing step, adding H 2 O 2  resulted in a 7.644% dilution factor. 
               
               
                 **In calculating total % removal, 7.644% dilution factor taken into consideration. (e.g., TDS Concentration of Treated Frac Water (Step 2) (U) after considering a 7.644% dilution factor = 157,160 mg/L. So, Total % TSS removal = ((205,000 − 157,160)/205,000) × 100 ≅ 23%) 
               
             
          
         
       
     
     Experimental Trial 14 
     First (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate Followed by Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=30 min (0.5 hour) 
     3. Filtered Sludge (R)=286 gm 
     4. Treated Frac Water (Q)=1,275 mL 
     Second (2 nd ) Processing Step—Catalytic Oxidation at High pH Followed by Filtration: 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=570 mL 
     2. Reaction time (τ)=50 min (0.83 hour) 
     3. Catalytic Metal Sludge (S)=286 gm 
     4. Treated Frac Water (U)=500 mL 
     See Table XIV below for the Experiment Trial 14 Results: 
     Note: In this unit operation, 570 mL was used from Treated Frac Water (Q). The remaining water was used for water testing. 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XIV 
               
             
             
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                   
                 2 nd  Processing Step 
                   
               
               
                   
                   
                   
                 Catalyst to Frac Water 
                   
               
               
                   
                   
                   
                 ratio = 250 g/L 
                   
               
               
                   
                   
                   
                 H 2 O 2  conc. = 0.97M 
                   
               
               
                   
                   
                   
                 solution 
                   
               
               
                   
                   
                   
                 Catalyst to H 2 O 2  (100%)  
                   
               
               
                   
                   
                 1 st  Processing Step 
                 ratio = 7 g/g 
                   
               
               
                   
                   
                 FeSO 4  to Frac Water ratio = 
                 NaOH to Frac Water 
                   
               
               
                   
                   
                 48.66 g/L 
                 ratio = 52.63 g/L 
                 Analyte Removal (%) 
               
             
          
           
               
                       Sr.  No. 
                         Analyte 
                     Untreated Frac Water (D) 
                 Treated Frac Water (Step 1) (Q) 
                   Diluted Concentration (Step 1) (Y) * 
                 Treated Frac Water (Step 2) (U) 
                   
                     Step   ⁢           ⁢   1     =                   D   -   Q     D     ×   100               
 
                   
                     Step   ⁢           ⁢   2     =                   Y   -   U     Y     ×   100               
 
                   
                     Total   **     =                   D   -   U     U     ×   100               
 
               
               
                   
               
             
          
           
               
                  1. 
                 pH 
                 3.71 
                 2.32 
                 — 
                 12.36 
                 — 
                 — 
                 — 
               
               
                  2. 
                 Calcium 
                 13,800 
                 4,010 
                 3,703 
                 6 
                 71 
                 100 
                 100 
               
               
                  3. 
                 Iron 
                 103 
                 11,800 
                 10,898 
                 ND 
                 −11,356 
                 100 
                 100 
               
               
                  4. 
                 Barium 
                 451 
                 0.038 
                 0.035 
                 0.094 
                 100 
                 −168 
                 100 
               
               
                  5. 
                 Strontium 
                 2,690 
                 831 
                 767 
                 15 
                 69 
                 98 
                 99 
               
               
                  6. 
                 Hardness 
                 38,231 
                 13,116 
                 12,114 
                 17 
                 66 
                 100 
                 100 
               
               
                  7. 
                 Sulfate 
                 109 
                 2,420 
                 2,235 
                 2,430 
                 −2,120 
                 −9 
                 −2,300 
               
               
                  8. 
                 Zinc 
                 0.57 
                 1.50 
                 1.40 
                 33.2 
                 −163 
                 −2,297 
                 −6,170 
               
               
                  9. 
                 TSS 
                 1,020 
                 212 
                 196 
                 211 
                 79 
                 −8 
                 78 
               
               
                 10. 
                 Potassium 
                 3,440 
                 1,960 
                 1,810 
                 2,150 
                 43 
                 −19 
                 33 
               
               
                 11. 
                 Magnesium 
                 910 
                 754 
                 696 
                 0.75 
                 17 
                 100 
                 100 
               
               
                 12. 
                 Chloride 
                 145,000 
                 114,000 
                 105,285 
                 101,000 
                 21 
                 4 
                 25 
               
               
                 13. 
                 Lithium 
                 100 
                 91 
                 84 
                 77 
                 9 
                 9 
                 17 
               
               
                 14. 
                 TDS 
                 205,000 
                 172,000 
                 158,852 
                 183,000 
                 16 
                 −15 
                 4 
               
               
                 15. 
                 Sodium 
                 46,900 
                 36,400 
                 33,617 
                 60,800 
                 22 
                 −81 
                 −40 
               
               
                   
               
               
                 * In the 2nd processing step, adding H 2 O 2  resulted in a 7.644% dilution factor. 
               
               
                 **In calculating total % removal, 7.644% dilution factor taken into consideration. (e.g., TDS Concentration of Treated Frac Water (Step 2) (U) after considering a 7.644% dilution factor = 108,720 mg/L. So, Total % TSS removal = ((145,000 − 108,720)/145,000) × 100 ≅ 25%) 
               
             
          
         
       
     
     Experimental Trial 15 
     First (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate Followed by Filtration: 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=30 min (0.5 hour) 
     3. Filtered Sludge (R)=94 gm 
     4. Treated Frac Water (Q)=1,410 mL 
     Second (2 nd ) Processing Step—Catalytic Oxidation at High pH Followed by Filtration: 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=570 mL 
     2. Reaction time (τ)=34 min (0.56 hour) 
     3. Catalytic Metal Sludge (S)=100 gm 
     4. Treated Frac Water (U)=490 mL 
     Note: In this unit operation, 570 mL was used from Treated Frac Water (Q). The remaining water was used for water testing. 
     See Table XV below for the Experiment Trial 15 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                   
                 2 nd  Processing Step 
                   
               
               
                   
                   
                   
                 Catalyst to Frac Water 
                   
               
               
                   
                   
                   
                 ratio = 25 g/L 
                   
               
               
                   
                   
                   
                 H 2 O 2  conc. = 0.1M 
                   
               
               
                   
                   
                   
                 solution 
                   
               
               
                   
                   
                   
                 Catalyst to H 2 O 2   
                   
               
               
                   
                   
                 1 st  Processing Step 
                 (100%) ratio = 7 g/g  
                   
               
               
                   
                   
                 FeSO 4  to Frac Water 
                 NaOH to Frac Water 
                   
               
               
                   
                   
                 ratio = 4.86 g/L 
                 ratio = 15.78 g/L 
                 Analyte Removal (%) 
               
             
          
           
               
                       Sr. No. 
                         Analyte 
                     Untreated Frac Water (D) 
                 Treated Frac Water (Step 1) (Q) 
                   Diluted Concentration (Step 1) (Y) * 
                 Treated Frac Water (Step 2) (U) 
                   
                     Step   ⁢           ⁢   1     =                   D   -   Q     D     ×   100               
 
                   
                     Step   ⁢           ⁢   2     =                   Y   -   U     Y     ×   100               
 
                   
                   Total   =                   D   -   U     U     ×   100               
 
               
               
                   
               
             
          
           
               
                  1. 
                 pH 
                 3.64 
                 2.98 
                 — 
                 11.17 
                 — 
                 — 
                 — 
               
               
                  2. 
                 Calcium 
                 13,800 
                 10,200 
                 10,116 
                 7,670 
                 26 
                 24 
                 44 
               
               
                  3. 
                 Iron 
                 103 
                 963 
                 955 
                 ND 
                 −835 
                 100 
                 100 
               
               
                  4. 
                 Barium 
                 451 
                 0.94 
                 0.93 
                 1.3 
                 100 
                 −39 
                 100 
               
               
                  5. 
                 Strontium 
                 2,690 
                 1,800 
                 1,785 
                 1,940 
                 33 
                 −9 
                 27 
               
               
                  6. 
                 Hardness 
                 38,231 
                 28,382 
                 28,149 
                 19,380 
                 26 
                 31 
                 49 
               
               
                  7. 
                 Sulfate 
                 109 
                 1,280 
                 1,269 
                 1,110 
                 −1074 
                 13 
                 −927 
               
               
                  8. 
                 Zinc 
                 0.570 
                 0.560 
                 0.555 
                 0.20 
                 2 
                 64 
                 65 
               
               
                  9. 
                 TSS 
                 1,020 
                 31 
                 31 
                 58 
                 97 
                 −86 
                 94 
               
               
                 10.  
                 Potassium 
                 3,440 
                 1,760 
                 1,746 
                 2,060 
                 49 
                 −18 
                 40 
               
               
                 11.  
                 Magnesium 
                 910 
                 703 
                 697 
                 50 
                 23 
                 93 
                 94 
               
               
                 12.  
                 Chloride 
                 145,000 
                 131,000 
                 129,924  
                 117,000 
                 10 
                 10 
                 19 
               
               
                 13.  
                 Lithium 
                 100 
                 77 
                 76 
                 85 
                 23 
                 −11 
                 14 
               
               
                 14.  
                 TDS 
                 205,000 
                 196,000 
                 194,391  
                 195,000 
                 4 
                 −0.31 
                 4 
               
               
                 15.  
                 Sodium 
                 46,900 
                 36,300 
                 36,002 
                 49,400 
                 23 
                 −37 
                 −6 
               
               
                   
               
               
                 * In the 2 nd  processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
               
                 ** In calculating total % removal, 0.82% dilution factor taken into consideration. (e.g.,TDS Concentration of Treated Frac Water (Step 2) (U) after considering a 0.82% dilution factor = 196,599 mg/L. So, Total % TSS removal = ((205,000 − 196,599)/205,000) × 100 ≅ 4%) 
               
             
          
         
       
     
     Experimental Trial 16 
     First (1 st ) Processing Step—Metal Precipitation by Ferrous Sulfate Followed by Filtration 
     1. Volume of Frac Water (D)=1,500 mL 
     2. Reaction time (τ)=30 min (0.5 hour) 
     3. Filtered Sludge (R)=19 gm 
     4. Treated Frac Water (Q)=1,450 mL 
     Second (2 nd ) Processing Step—Catalytic Oxidation at High pH Followed by Filtration: 
     1. Volume of Treated Frac Water (Q) from 1 st  processing step=1,000 mL 
     2. Reaction time (τ)=38 min (0.63 hour) 
     3. Catalytic Metal Sludge (S)=157 gm 
     4. Treated Frac Water (U)=870 mL 
     Note: In this unit operation, 570 mL was used from Treated Frac Water (Q). The remaining water was used for water testing. 
     See Table XVI below for the Experiment Trial 16 Results: 
     
       
         
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE XVI 
               
             
             
               
                   
               
               
                   
                   
                 Analyte Concentration (mg/L or ppm) 
                   
               
             
          
           
               
                   
                   
                   
                 2 nd  Processing Step 
                   
               
               
                   
                   
                   
                 Catalyst to Frac Water 
                   
               
               
                   
                   
                   
                 ratio = 25 g/L 
                   
               
               
                   
                   
                   
                 H 2 O 2  conc. = 0.1M 
                   
               
               
                   
                   
                   
                 solution 
                   
               
               
                   
                   
                   
                 Catalyst to H 2 O 2    
                   
               
               
                   
                   
                   
                 (100%)  
                   
               
               
                   
                   
                 1 st  Processing Step 
                 ratio = 7 g/g 
                   
               
               
                   
                   
                 FeSO 4  to Frac Water 
                 NaOH to Frac Water 
                   
               
               
                   
                   
                 ratio = 4.86 g/L 
                 ratio = 8 g/L 
                 Analyte Removal (%) 
               
             
          
           
               
                       Sr. No. 
                         Analyte 
                     Untreated Frac Water (D) 
                 Treated Frac Water (Step 1) (Q) 
                   Diluted Concentration (Step 1) (Y) * 
                 Treated Frac Water (Step 2) (U) 
                   
                     Step   ⁢           ⁢   1     =                   D   -   Q     D     ×   100               
 
                   
                     Step   ⁢           ⁢   2     =                   Y   -   U     Y     ×   100               
 
                   
                   Total   =                   D   -   U     U     ×   100               
 
               
               
                   
               
             
          
           
               
                  1. 
                 pH 
                 4.09 
                 5.64 
                 — 
                 11.22 
                 — 
                 — 
                 — 
               
               
                  2. 
                 Calcium 
                 6,900 
                 6,100 
                 6,050 
                 5,300 
                 12 
                 12 
                 23 
               
               
                  3. 
                 Iron 
                 22 
                 1,700 
                 1,686 
                 1.2 
                 −7,627 
                 100 
                 95 
               
               
                  4. 
                 Barium 
                 740 
                 0.35 
                 0.35 
                 0.19 
                 100 
                 45 
                 100 
               
               
                  5. 
                 Strontium 
                 1,500 
                 1,200 
                 1190 
                 1,100 
                 20 
                 8 
                 26 
               
               
                  6. 
                 Hardness 
                 19,915 
                 17,587 
                 17,443 
                 17,299 
                 12 
                 1 
                 12 
               
               
                  7. 
                 Sulfate 
                 360 
                 2,000 
                 1,984 
                 1,500 
                 −456 
                 24 
                 −320 
               
               
                  8. 
                 Zinc 
                 0.25 
                 0.59 
                 0.59 
                 0.25 
                 −136 
                 57 
                 −1 
               
               
                  9. 
                 TSS 
                 140 
                 20 
                 20 
                 110 
                 86 
                 −455 
                 21 
               
               
                 10. 
                 Potassium 
                 690 
                 600 
                 595 
                 710 
                 13 
                 −19 
                 −4 
               
               
                 11. 
                 Magnesium 
                 650 
                 570 
                 565 
                 2.1 
                 12 
                 100 
                 100 
               
               
                 12. 
                 Chloride 
                 59,000 
                 61,000 
                 60,499 
                 57,000 
                 −3 
                 6 
                 3 
               
               
                 13. 
                 Lithium 
                 49 
                 44 
                 44 
                 49 
                 10 
                 −12 
                 −1 
               
               
                 14. 
                 TDS 
                 110,000 
                 85,000 
                 84,302 
                 97,000 
                 23 
                 −15 
                 11 
               
               
                 15. 
                 Sodium 
                 26,000 
                 24,000 
                 23,803 
                 32,000 
                 8 
                 −34 
                 −24 
               
               
                   
               
               
                 * In the 2 nd  processing step, adding H 2 O 2  resulted in a 0.82% dilution factor. 
               
               
                 ** In calculating total % removal, 0.82% dilution factor taken into consideration. (e.g., TDS Concentration of Treated Frac Water (Step 2) (U) after considering a 0.82% dilution factor = 97,795 mg/L. So, Total % TSS removal = ((110,000 − 97,795)/110,000) × 100 ≅ 11% 
               
             
          
         
       
     
     In summary, based on the above experimental trials conducted, the minimum % reduction of analytes achieved in  FIG. 1  (Innovative Process 1),  FIG. 4  (Innovative Process 2), and  FIG. 5  (Innovative Process 3) is shown in the below Table D. 
     
       
         
               
               
               
               
               
             
           
               
                   
               
               
                   
                   
                 Cosmos 
                 Cosmos 
                 Cosmos 
               
               
                   
                   
                 Innovative 
                 Innovative 
                 Innovative 
               
               
                   
                 Minimum % Reduction 
                 Process 1 
                 Process 2 
                 Process 3 
               
               
                 Sr. No. 
                 of Analyte 
                 (FIG. 1) 
                 (FIG. 4) 
                 (FIG. 5) 
               
               
                   
               
             
             
               
                 1. 
                 Iron 
                 95 
                 95 
                 95 
               
               
                 2. 
                 Calcium 
                 95 
                 — 
                 95 
               
               
                 3. 
                 Barium 
                 90 
                 45 
                 95 
               
               
                 4. 
                 Strontium 
                 75 
                 — 
                 95 
               
               
                 5. 
                 Magnesium 
                 35 
                 — 
                 95 
               
               
                 6. 
                 TSS 
                 85 
                 — 
                 75 
               
               
                 7. 
                 Hardness 
                 85 
                 — 
                 95 
               
               
                   
               
             
          
         
       
     
     While the disclosure has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the embodiments. Thus, it is intended that the present disclosure cover the modifications and variations of this disclosure provided they come within the scope of the appended claims and their equivalents