Abstract:
Introducing a high surface area media into a sewage treatment process to improve and increase capacity of a given process. The high surface area media can be dispersed at strategic locations in a new or existing attached growth wastewater treatment plant so as to provide additional sites for biological growth and improved wastewater renovation.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention pertains to a method and apparatus for the treatment of wastewaters, more specifically, sanitary wastewaters, with a combination of materials, apparatus and equipment for both improvement of the treatment processes as well as the creation of additional treatment capacity. More particularly, the present invention pertains to a method and apparatus for modifying an attached growth process employing biofilms with high surface area materials as well as suspended attached growth processes as either intermittently or continuously feeding of zeolitic material. 
         [0002]    Over the past 20-30 years there has been an increase in the use of the Attached Systems in the wastewater treatment processes because of the inherently more efficient settling and stable and higher treatment efficiency. Attached growth process are Trickling Filters, Rotating Biological Contactors, IFAS (Integrated Fixed Film Activated Sludge), MBBR (Moving Bed Biofilm Reactors), RBC (rotating Biofilm Reactors). Denitrification filters including but not limited to conventional flow through rock or plastic media trickling filter modifications as well as submerged growth reactors. 
         [0003]    Trickling filter reactors are large tanks filled with rock or plastic media upon which the wastewater is applied over the surface either continuously or intermittently and allowed to trickle down over the media. The filters have either passive or forced draft air ventilation system. 
         [0004]    Wide variations in both the hydraulic and biological loading as well as temperature in attached growth sewage treatment process give rise to numerous operating problems as well as process inefficiency. Attached biofilm reactors become problematic when the wastewater volume or wastewater characteristics exceed the ranges designed for the systems. Any agent or combination of agents that can improve or expand the range of the operation band for attached growth type plants, will improve the operating efficiency as well as compliance excursions with effluent standards as well as being cost effective. 
         [0005]    Zeolites have been successfully employed for improved wastewater treatment plant performance in accordance with the published literature and can provide a stabilizing effect during both long term and short term so fluctuations in sludge settleablilty and bacterial mass growth in sewage treatment plants are improved. It provides not only a weighting agent for increasing the sludge settling characteristics but also a platform for bacterial growth which performs a function similar to that of an attached growth media systems. 
         [0006]    The use of zeolitic materials on various support media for sewage treatment has been documented. A prior art search specifically for zeolite attached to these materials is republished in the following patents: 
         [0000]    
       
         
               
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Patentee 
                 Patent No. 
                 Filing Date 
                 Issue Date 
               
               
                   
                   
               
             
             
               
                   
                 Stuth 
                 7,252,766 
                 February 2005 
                 Aug. 7, 2007 
               
               
                   
                 Horing 
                 6,855,255 
                 January 2003 
                 Feb. 15, 2005 
               
               
                   
                 DeFilippie 
                 6,395,522 
                 January 1994 
                 May 22, 2002 
               
               
                   
                 Heitkamp 
                 5,980,738 
                 October 1996 
                 Nov. 9, 1999 
               
               
                   
                 Sanyal 
                 5,217,616 
                 December 1991 
                 Jun. 8, 1993 
               
               
                   
                 Lupton 
                 4,983,299 
                 April 1989 
                 Jan. 8, 1991 
               
               
                   
                   
               
             
          
         
       
     
         [0007]    The above referenced patents employ a method of attachment of the zeolite or other materials to the support material. These all employ a packed bed reactor through which the wastewater is forced. Another example of prior art are the following patents: 
         [0000]    
       
         
               
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Patentee 
                 Patent No. 
                 Filing Date 
                 Issue Date 
               
               
                   
                   
               
             
             
               
                   
                 Smith 
                 7,452,468 
                 September 2006 
                 November 2008 
               
               
                   
                 Smith 
                 7,507,342 
                 February 2007 
                 March 2009 
               
               
                   
                   
               
             
          
         
       
     
         [0008]    These patents are based on the dosing of either the zeolite and bacteria or both zeolite and bacteria into wastewater treatment plant which employs a form of activated sludge processing retrofitted with media, as well as attached growth processes. In these patents materials are separate and unsupported dosed materials applied to trickling filter or rotating biological contractor, integrated fixed film activated sludge wastewater treatment processes. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is a method for improving the treatment of wastewater, e.g. sanitary wastewater in an attached growth biofilm wastewater process such as trickling filters, rotating biological contactors, integrated fixed film activated sludge or Moving Bed Biofilm Reactors or fixed bed reactor, employing rock or plastic media either stationary or rotating through the wastewater or suspended in the reactor by the addition or feeding of zeolitic or high surface area materials as a dosed material which is added to the wastewater as it is applied to the reactor. Feeding of the zeolitic material is defined as the addition of the zeolite material directly into the aerated or mixed reactors or by the feeding of the zeolitic material into a wastewater stream feeding directly into the reactors or a recirculation stream that discharges into the reactors. The term “hybrid media processing” has been employed to describe a conventional trickling filter or rotating biological contactor, integrated fixed film activated sludge or Moving Bed Biofilm Reactors that employ both conventional media and the dosed high surface area media. The term “hybrid rotating biological contactor” has been employed to describe a conventional rotating biological contactor that employs both conventional media and the dosed high surface area media. 
         [0010]    Incorporation of zeolitic materials in trickling filter, rotating biological contactor, integrated fixed film activated sludge or Moving Bed Biofilm Reactors or other attached growth reactors will improve the overall efficiency of the process. 
         [0011]    The zeolitic material can be dispersed into an attached growth reactor or the bioreactors of a conventional flow through process by the dosage of the zeolitic material into the applied wastewater stream to the reactors. The zeolitic material can be applied dry or as a liquid mixture or slurry. 
         [0012]    Therefore, in one aspect the present invention is a method for improving a wastewater treating process employing one of trickling filter process, a rotating biological contactor process integrated fixed film activated sludge or Moving Bed Biofilm Reactors comprising the step of introducing into said trickling filter, rotating biological contactor, integrated fixed film activated sludge or Moving Bed Biofilm Reactor treatment process a quantity of separate and unsupported natural zeolitic material being one of clinoptilolite, mordenite, chabazite or phillipsite, for better liquid solid separation; removal of ammonia, denitrification, removal of carbonaceous material, reduction of surfactant interference with liquid solid separation, and provide a balanced nutrient formulation in the wastewater. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The present invention will hereinafter be described in conjunction with the appended drawing figures wherein like numerals denote like elements. 
           [0014]      FIG. 1  is a plot of the zeolite dose against effluent COD. As the dosage is increased so is the amount of surface area and therefore the decrease in the amount of COD. 
           [0015]      FIG. 2  is a plot of the zeolite dose against equivalent media surface area present in the reactor as a result of the amount of zeolite added. 
           [0016]      FIG. 3  is a plot of the zeolite dose against effluent TKN. Total Kjeldahl Nitrogen or TKN is the sum of organic nitrogen, ammonia (NH3), and ammonium (NH4+) in the chemical analysis of soil, water, or wastewater (e.g. sewage treatment plant effluent). To calculate Total Nitrogen (TN), the concentrations of nitrate-N and nitrite-N are determined and added to TKN. 
           [0017]      FIG. 4A  is a schematic representation of point of application of zeolite at the point where the primary effluent from the primary clarifier is mixed with a portion of the effluent from the Trickling Filter for recycle to the Trickling Filter. 
           [0018]      FIG. 4B  is schematic representation of the application of the zeolite into the effluent from the primary classifier prior to injection into the Trickling Filter. 
           [0019]      FIG. 4C  is schematic representation of the application of the zeolite to the primary effluent from the primary classifier mixed with a portion of the effluent from a secondary Trickling Filter prior to injection into a first Trickling Filter and application of the zeolite to the effluent of the first Trickling Filter prior to injection into the second Tickling Filter. 
           [0020]      FIG. 4D  is a schematic representation of the application of the zeolite in a process featuring multiple clarifiers and multiple Tickling Filters where the first zeolite application point is into the effluent from the primary classifier mixed with a portion of the recycle from the first Trickling Filter and the second zeolite application point is in the effluent from an intermediate clarifier mixed with a portion of the recycle from a secondary Trickling Filter prior to injection into the second Trickling Filter. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]    The following detailed description provides preferred exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the ensuing detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments of the invention. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention, as set forth in the appended claims. 
         [0022]    The following equation is normally employed for estimating the removal of nitrogen by a trickling filter. The nitrification rate units are lb-N/ft̂2/day. This equation therefore is dependent upon the surface area of the tricking filter for the media employed in the trickling filter. The smaller the carbon to nitrogen ratio the higher is the nitrification rate. This is due to the preferential oxidation of the carbon before the nitrogen. This equation does not specifically employ any recirculation rate considerations but can take into it into consideration if it is included in the Carbon &amp; Nitrogen loading onto the trickling filter. This equation is empirically based on the ratio of the applied Carbon loading to Total Kjeldahl Nitrogen loading onto the trickling filter using empirically developed correction coefficients 
         [0000]    
       
         
           
             
               
                 
                   NitriRate 
                   = 
                   
                     0.82 
                     · 
                     
                       
                         [ 
                         
                           Si 
                           RawTKN 
                         
                         ] 
                       
                       
                         ( 
                         
                           - 
                           0.44 
                         
                         ) 
                       
                     
                   
                 
               
               
                 
                   Equation 
                    
                   
                       
                   
                    
                   1 
                 
               
             
           
         
       
     
         [0023]    Using the data below and solving Equation 1, one arrives at a nitrification rate of 0.00012 lb-N/ft̂2/day. 
         [0024]    All of the data reported in Tables 1-7 was generated by mathematical model. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                 NitriRate 
                 0.00012 
                 Lb-N/ft {circumflex over ( )} 2/day 
                 Nitrification Rate Oakley 
               
               
                   
                   
                   
                   
                   
                 Albertson Nitrification Rate 
               
               
                   
                   
                 Si 
                 207 
                 mg/l 
                 COD Loading onto Filter 
               
               
                   
                 86 
                 RawNH3 
                   
                 mg/l 
                 Influent NH3 concentration 
               
               
                   
                 0.85 
                 TKNfactor 
                   
                   
                 Ratio factor of NH2 to TKN 
               
               
                   
                   
               
             
          
         
       
     
         [0025]    Equation 2 can be employed to compute the value of the applied TKN if the ratio of the TKN to Ammonia (NH3) is known. The value of 0.85 shown in Table 1 is a commonly employed value for domestic wastewater. 
         [0000]    
       
         
           
             
               
                 
                   RawTKN 
                   = 
                   
                     
                       RawNH 
                        
                       
                           
                       
                        
                       3 
                     
                     TKNfactor 
                   
                 
               
               
                 
                   Equation 
                    
                   
                       
                   
                    
                   2 
                 
               
             
           
         
       
     
         [0026]    Equation #3 is the standard equation employing the total fixed media surface area, a factor and the Nitrification to determine the mass of ammonia (NH3) removed by a trickling filter with a given amount of surface area based on the media employed in the filter. 
         [0000]      NH3removed_Std=(ÓFixedArea.0.0283.NitriRate)  Equation 3
 
         [0027]    Two parallel trickling filters with the total surface area of 27,695 square feet of rock media having a specific surface area of 15 square feet of surface area per cubic foot of media were loaded at 12,000 gallons per day with the loadings shown in Table 1. Table 2 shows the trickling filter specifics for this installation. The filters were preceded by an equalization basin and a single primary clarifier. The value of Si used in the loading equation was after assigning a 35% COD removal efficiency for the primary clarifier and a filter recycle rate of 400%. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 FilterArea 
                 307.72 
                 ft {circumflex over ( )} 2 
                 Estimated Hickory Run 
               
               
                   
                   
                   
                   
                 Filter Area 
               
               
                   
                 ΣFilterVol 
                 1,846 
                 ft {circumflex over ( )} 3 
                 Total Filters Volume 
               
               
                   
                 ΣFixed Area 
                 27,695 
                 ft {circumflex over ( )} 2 
                 Total Filters Surface Area 
               
               
                   
                   
                   
                   
                 Fixed Media 
               
               
                   
                 FixMediaSurfaceArea 
                 15 
                 ft {circumflex over ( )} s/ft {circumflex over ( )} 3 
                 Media Type Surface Area 
               
               
                   
                   
               
             
          
         
       
     
         [0028]    Employing Equation 3 the mass of NH3 predicted to be removed is 10.3 lb per day as is shown in Table 3. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 NH3removed_Std 
                 10.3 
                 lb/day 
                 TKN removal based on 
               
               
                   
                   
                   
                   
                 conventional Media 
               
               
                   
                   
                   
                   
                 Surface Area 
               
               
                   
                   
               
             
          
         
       
     
         [0029]    Table 4 below shows a model for the same trickling filter plant to which has been added 5 pounds per day of a zeolitic material according to the present invention. The zeolite has a specific surface area of 29,500 square feet per pound. It has been reported in the literature that 98% of zeolite is removed from a trickling filter plant. This includes removal in both the primary and final clarifiers as well as any material enmeshed in the biofilm on the trickling filter. In the trickling filter plant being discussed the zeolite was dosed to an aerated recirculation sump after the two primary trickling filters which then recirculate back to the influent to the two rock trickling filters. Field data indicated that 3.3% of the dosed zeolite surface area was effective in increasing the total surface area in the trickling filters. 
         [0030]    Table 4 indicates that an additional 4,868 square feet of surface area is being added daily to the trickling filter media by the addition of the zeolite. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 4 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 L 
                 5 
                 ZeroMassDose 
                   
                 lb/day 
                 Dosage of zeolite 
               
               
                   
                   
                 ZeoliteConc 
                 50 
                 mg/l 
                 Zeolite Concentration 
               
               
                   
                   
                   
                   
                   
                 Dosage based on flow 
               
               
                   
                 29,500 
                   
                   
                 ft {circumflex over ( )} 2/lb 
                 Surface Area of Zeolite 
               
               
                   
                 0.033 
                 ZeoliteEffective 
                   
                 Decimal 
                 Zeolite Effective Area 
               
               
                   
                   
                   
                   
                   
                 factor 
               
               
                   
                   
                 ΣZeoliteAreaAdded 
                 147,500 
                 ft {circumflex over ( )} 2/day 
                 Total Zeolite Surface Area 
               
               
                   
                   
                   
                   
                   
                 Added 
               
               
                   
                   
                 DailyZeoliteArea 
                 4,868 
                 ft {circumflex over ( )} 2 
                 Effective Surface Area 
               
               
                   
                   
                   
                   
                   
                 added daily 
               
               
                   
                   
                 ΣZeoliteBiofilm 
                 97,350 
                 ft {circumflex over ( )} 2 
                 Total Zeolite Area 
               
               
                   
                   
                   
                   
                   
                 @Biofilm Age 
               
               
                   
               
             
          
         
       
     
         [0031]    In trickling filter plants just as in Activated Sludge wastewater plants there is an age to the bacteria. In Activated Sludge it is determined by sludge wasting whereas in a trickling filter plant it is controlled by the biofilm growth and resulting sloughing of the biofilm off the media. Using the numbers shown in the model and a sloughing rate of 5% one has a 20 day biofilm age and a 97,350 square feet of additional surface area due to the zeolite. This results in a total effective surface area of the 27,695 square feet due to the rock media plus the 97,350 square feet due to the zeolite (3.3% effective area for the zeolite as explained previously) for a 352% increase in total surface area. The net effect of this is that it has the same effect as removing the rock media and replacing it with plastic media having a specific surface area of 67.73 square feet per cubic foot without additional capital costs. 
         [0032]    Table 5 indicates that the volumetric loading rates, a measure of carbonaceous material materials, are dramatically improved as well. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 5 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                 ====&gt; Conventional 
               
               
                   
                   
                   
                   
                   
                 Trickling Filter Design 
               
               
                   
                   
                   
                   
                   
                 Calculations &lt;==== 
               
               
                   
                   
                 Si 
                 207 
                 mg/l 
                 COD Loading onto Filter 
               
               
                   
                 12,000 
                 Q 
                   
                 gpd 
                 Raw Sewage Flow 
               
               
                   
                 675 
                 So 
                   
                 mg/l 
                 Primary Effluent COD 
               
               
                   
                   
                   
                   
                   
                 (can use BOD) 
               
               
                   
                 4 
                 a 
                   
                   
                 Ratio of Return Flow to 
               
               
                   
                   
                   
                   
                   
                 Raw Flow 
               
               
                   
                 90 
                 Se 
                   
                 mg/l 
                 Trickling Filter Effluent 
               
               
                   
                   
                   
                   
                   
                 COD 
               
               
                   
                 0.39 
                 K1 
                   
                 min {circumflex over ( )} -1 
                 Organic removal velocity 
               
               
                   
                   
                   
                   
                   
                 constant @ T1 
               
               
                   
                 1.04 
                 Theta 
                   
                   
                 Temperature coefficient 
               
               
                   
                   
                   
                   
                   
                 (1.1 to 1.35) 
               
               
                   
                 18 
                 T2 
                   
                   
                 Water Temperature Actual 
               
               
                   
                   
                   
                   
                   
                 Deg. C. 
               
               
                   
                 20 
                 T1 
                   
                   
                 Water Temperature Ideal 
               
               
                   
                   
                   
                   
                   
                 20 Deg. C. 
               
               
                   
                   
                 Av 
                 15 
                 sqft/cuft 
                 Specific Surface of Media 
               
               
                   
                 6 
                 D 
                   
                 ft 
                 Media Depth 
               
               
                   
                   
                 q 
                 0.54 
                 gpm/sqft 
                 Hydraulic loading onto 
               
               
                   
                   
                   
                   
                   
                 filter - media only 
               
               
                   
                   
                 n 
                 2.71 
                   
                 Visilind ‘n’ after Vicarri 
               
               
                   
                   
                   
                   
                   
                 2007 
               
               
                   
                 14 
                 d 
                   
                 ft 
                 Diameter of Filter 
               
               
                   
                   
                 Qr 
                 48,000 
                 gpd 
                 Recirculation Flow 
               
               
                   
                   
                 Er 
                 86.67 
                 % 
                 COD Removal Efficiency 
               
               
                   
                 2 
                 Filter# 
                   
                   
                 Number of Filters 
               
               
                   
                   
                 FilterArea 
                 307.72 
                 ft {circumflex over ( )} 2 
                 Estimated Hickory Run 
               
               
                   
                   
                   
                   
                   
                 Filter Area 
               
               
                   
                   
                 ΣFilterVol 
                 1,846 
                 ft {circumflex over ( )} 3 
                 Total Filters Volume 
               
               
                   
                   
                 ΣFixedArea 
                 27,695 
                 ft {circumflex over ( )} 2 
                 Total Filters Surface Area 
               
               
                   
                   
                   
                   
                   
                 Fixed Media 
               
               
                   
                   
                 FixedMediaSurfaceArea 
                 15 
                 ft {circumflex over ( )} 2/ft {circumflex over ( )} 3 
                 Media Type Surface Area 
               
               
                   
                   
                 FixedMediaLoadingRate 
                 36.59 
                 lb COD/ 
                 Conventional Loading 
               
               
                   
                   
                   
                   
                 1000 Ft {circumflex over ( )} 3 
                 Rates for Roc (5 to 20 
               
               
                   
                   
                   
                   
                   
                 lb/1000 ft {circumflex over ( )} 3) 
               
               
                   
                   
                 Vlr 
                 73.14 
                 lb/1000 ft {circumflex over ( )} 3 
                 Organic Volume Loading 
               
               
                   
                   
                   
                   
                   
                 (w/recirc.) lb/1000 cuft 
               
               
                   
                   
                 Vl 
                 112.15 
                 lb/1000 ft {circumflex over ( )} 3 
                 Organic Volume Loading 
               
               
                   
                   
                   
                   
                   
                 (w/recirc.) lb/1000 cuft 
               
               
                   
                   
                 HydLoading 
                 39 
                 gpd/ft {circumflex over ( )} 2 
                 Fixed Media Hydraulic 
               
               
                   
                   
                   
                   
                   
                 Loading Rate 
               
               
                   
                   
                 CODload 
                 67.55 
                 lb COD/ 
                 Estimated Plant COD 
               
               
                   
                   
                   
                   
                 day 
                 Loading 
               
               
                   
                   
                 HydClass 
                 ″Low 
                   
                 Hydraulic Filter Loading 
               
               
                   
                   
                   
                 Rate 
                   
                 Class based on physical 
               
               
                   
                   
                   
                   
                   
                 filter volume 
               
               
                   
                   
                 OrgLoadClass 
                 ″High 
                   
                 Organic Filter Loading 
               
               
                   
                   
                   
                 Rate 
                   
                 Class based on physical 
               
               
                   
                   
                   
                   
                   
                 filter volume 
               
               
                   
                   
                   
                   
                   
                 ====&gt; Zeolite 
               
               
                   
                   
                   
                   
                   
                 Calculations &lt;==== 
               
               
                 L 
                 5 
                 ZeoMassDose 
                   
                 lb/day 
                 Dosage of zeolite 
               
               
                   
                   
                 ZeoliteConc 
                 50 
                 mg/l 
                 Zeolite Concentration 
               
               
                   
                   
                   
                   
                   
                 Dosage based on flow 
               
               
                   
                 29,500 
                 ZeoliteArea 
                   
                 ft {circumflex over ( )} 2/lb 
                 Surface Area of Zeolite 
               
               
                   
                 0.033 
                 ZeoliteEffective 
                   
                 Decimal 
                 Zeolite Effective Area 
               
               
                   
                   
                   
                   
                   
                 factor 
               
               
                   
                   
                 ΣZeoliteAreaAdded 
                 147,500 
                 ft {circumflex over ( )} 2/day 
                 Total Zeolite Surface Area 
               
               
                   
                   
                   
                   
                   
                 Added 
               
               
                   
                   
                 DailyZeoliteArea 
                 4,868 
                 ft {circumflex over ( )} 2 
                 Effective Surface Area 
               
               
                   
                   
                   
                   
                   
                 added daily 
               
               
                   
                   
                   
                   
                   
                 ====&gt; Zeolite 
               
               
                   
                   
                   
                   
                   
                 Calculations &lt;==== 
               
               
                   
                   
                 BiofilmVolume 
                 577 
                 ft {circumflex over ( )} 3 
                 Biofilm Volume on Fixed 
               
               
                   
                   
                   
                   
                   
                 Media 
               
               
                   
                 0.25 
                 BiofilmThickness 
                   
                 inch 
                 Biofilm Thickness 
               
               
                   
                   
                 BiofilmMass 
                 5.2983 
                 lb 
                 Biofilm Mass 
               
               
                   
                   
                 BiofilmAge 
                 20 
                 days 
                 Equivalent Fixed Media 
               
               
                   
                   
                   
                   
                   
                 Age based on sloughing 
               
               
                   
                 0.05 
                 BiofilmSoughingRate 
                   
                 % 
                 Media Sloughing Rate % 
               
               
                   
                   
                 ΣZeoliteBiofilm 
                 97,350 
                 ft {circumflex over ( )} 2 
                 Total Zeolite Area @ 
               
               
                   
                   
                   
                   
                   
                 Biofilm Age 
               
               
                   
                   
                 SurfaceAreaIncrease 
                 352 
                 % 
                 Surface Area Increase % 
               
               
                   
                   
                   
                   
                   
                 using Biofilm Age Σ area 
               
               
                   
                   
                   
                   
                   
                 ====&gt; Zeolite 
               
               
                   
                   
                   
                   
                   
                 Calculations &lt;==== 
               
               
                   
                   
                 Vlhybrid 
                 12.43 
                 lb/1000 ft {circumflex over ( )} 3 
                 Volume Loading 
               
               
                   
                   
                   
                   
                   
                 (w/recirc.) lb/1000 cuft 
               
               
                   
                   
                 Vlryhbrid 
                 2.49 
                 lb/1000 ft {circumflex over ( )} 3 
                 Volume Loading 
               
               
                   
                   
                   
                   
                   
                 (w/recirc.) lb/1000 cuft 
               
               
                   
                   
                 ΣCombinedArea 
                 125,045 
                 ft {circumflex over ( )} 2 
                 Total Effective Surface 
               
               
                   
                   
                   
                   
                   
                 Area in Filters 
               
               
                   
                   
                 EqTotalVol 
                 8,336 
                 ft {circumflex over ( )} 3 
                 Equivalent Filter Volume 
               
               
                   
                   
                   
                   
                   
                 for both Media 
               
               
                   
                   
                 HybridLoadingRate 
                 0.54 
                 lb COD/ 
                 Organic Loading Rate for 
               
               
                   
                   
                   
                   
                 1000 ft {circumflex over ( )} 3 
                 Hybrid 
               
               
                   
                   
                 Sehybrid 
                 0 
                 mg/l 
                 Effluent COD hybrid 
               
               
                 L 
                   
                 Avhybrid 
                 67.73 
                 ft {circumflex over ( )} 2/ft {circumflex over ( )} 3 
                 Equivalent Surface Area 
               
               
                   
                   
                   
                   
                   
                 based on filter volume 
               
               
                   
                   
                 Qhybrid 
                 0.005 
                 gpm/sqft 
                 Hybrid loading onto Σ 
               
               
                   
                   
                   
                   
                   
                 filter surface area 
               
               
                   
               
             
          
         
       
     
         [0000]      NH3removed=(ÓCombinedArea.0.0283.NitriRate)  Equation 4
 
         [0033]    Table 6 shows the mathematical model calculated nitrification rate base on the data shown in Table 5 and as calculated by Equation 1 and shown in Table 1. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 6 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 NitriRate 
                 0.00012 
                 lb-N/ft {circumflex over ( )} 2/day 
                 Nitrification Rate 
               
               
                   
                   
                   
                   
                 Oakley Albertson 
               
               
                   
                   
                   
                   
                 Nitrification Rate 
               
               
                   
                   
               
             
          
         
       
     
         [0034]    Equation 4 is similar to Equation 3 with the only difference being total effective surface area. The Nitrification Rate as determined by Equation #1 can be employed in both Equation #3 and Equation #4. Now if one had a mathematical model for the trickling filter plant and empirical field data for both the influent and effluent Ammonia then though invertible iterative solving of the mathematical model one could arrive at the Nitrification Rate that was actually taking place in the plant under actual operation condition. Employing actual field data from the full scale hybrid trickling filter plant employing the zeolite and a Nitrification Rate increase of 0.00012 lb-N/ft̂2/day as shown in Table #6 the effective surface area of the added zeolite was determined to be 3.3%. Therefore the use of the zeolite has added additional surface area which in turn via both plant performance and mathematical modeling validates the increase in surface area created by the dosing of zeolite to a fixed media wastewater treatment process and the resulting improved trickling filter performance. The increase in ammonia removal was 40% based field data which confirms the increase in surface area. The effect of the zeolite is not solely a surface area phenomenon. The model has assumed that the nitrification rate stayed at a fixed value. In reality the improvement is due to both an increase in surface area and an increase in biological processes for both carbonaceous and nitrogenous materials. 
         [0035]    Table 7 is shows in input and output data from the mathematical model based on the field data. It should be noted that the “NitriRate” variable shown in Table 7 is the same as that shown in Table 6 and Table 1. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 7 
               
               
                   
               
               
                 Status 
                 Input 
                 Name 
                 Output 
                 Unit 
                 Comment 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                   
                   
                   
                   
                   
                 ====&gt; Primary Filter 
               
               
                   
                   
                   
                   
                   
                 Nitrification Calcula- 
               
               
                   
                   
                   
                   
                   
                 tions &lt;==== 
               
               
                   
                   
                 NitriRate 
                 0.00012 
                 lb-N/ft {circumflex over ( )} 2/day 
                 Nitrification Rate Oakley 
               
               
                   
                   
                   
                   
                   
                 Albertson Nitrification 
               
               
                   
                   
                   
                   
                   
                 Rate 
               
               
                   
                   
                 RawTKN 
                 101.18 
                 mg/l 
                 Raw TKN applied to 
               
               
                   
                   
                   
                   
                   
                 trickling filter 
               
               
                   
                 86 
                 RawNH3 
                   
                 mg/l 
                 Influent NH3 
               
               
                   
                   
                   
                   
                   
                 concentration 
               
               
                   
                 0.85 
                 TKNfactor 
                   
                   
                 Ratio factor of NH3 to 
               
               
                   
                   
                   
                   
                   
                 TKN 
               
               
                   
                   
                 RawTKNmass 
                 10.13 
                 lb/day 
                 Raw TKN Loading on 
               
               
                   
                   
                   
                   
                   
                 Filter 
               
               
                   
                   
                 NH3removed 
                 4.66 
                 lb/day 
                 TKN removal based on 
               
               
                   
                   
                   
                   
                   
                 combined Media Surface 
               
               
                   
                   
                   
                   
                   
                 Area 
               
               
                   
                   
                 NH3removed_Std 
                 10.03 
                 lb/day 
                 TKN removal based on 
               
               
                   
                   
                   
                   
                   
                 conventional Media 
               
               
                   
                   
                   
                   
                   
                 Surface Area 
               
               
                   
                   
                 TKNeffmasshydridel 
                 5.45 
                 lb/day 
                 TKN left with hybrid 
               
               
                   
                   
                   
                   
                   
                 surface media 
               
               
                   
                   
                 TKNeffmassstd 
                 9.09 
                 lb/day 
                 TKN left with standard 
               
               
                   
                   
                   
                   
                   
                 surface media 
               
               
                   
                   
                 EffTKNstd 
                 90.84 
                 mg/l 
                 Effluent TKN with 
               
               
                   
                   
                   
                   
                   
                 standard media 
               
               
                   
                   
                 EffTKNhybrid 
                 54.51 
                 mg/l 
                 Effluent TKN with hybrid 
               
               
                   
                   
                   
                   
                   
                 media 
               
               
                   
                   
                 NH3RemovalEff % 
                 40% 
                 % 
                 Hybrid Filter NH3 
               
               
                   
                   
                   
                   
                   
                 removal increase 
               
               
                   
                   
               
             
          
         
       
     
         [0036]    The data shown below in Table 8 is actual field data that has been measured in the field and employed in the mathematical models to evaluate the performance of the hybrid media processing. 
         [0000]    
       
         
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 8 
               
               
                   
               
               
                 Plant Flow 
                 Influent EQ 
                 Influent 
                 EQ Basin 
                 Eff Batch 
                 Eff Batch 
               
               
                 gpd 
                 NH3—N 
                 TKN 
                 COD 
                 NH3—N 
                 NO3—N 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 51,328 
                 38.4 
                   
                 419 
                 0.153 
                 1.640 
               
               
                 30,000 
                 31.2 
                   
                 376 
                 0.144 
                 0.930 
               
               
                 32,400 
                 30.6 
                   
                 620 
                 0.0159 
                 0.898 
               
               
                 31,700 
                 32.6 
                   
                 526 
                 0.064 
                 0.921 
               
               
                 35,500 
                 38.4 
                   
                 709 
                 0.026 
                 1.020 
               
               
                 30,598 
                 29.8 
                   
                 536 
                 0.012 
                 1.350 
               
               
                 36,782 
                 35.8 
                   
                 461 
                 0.053 
                 1.330 
               
               
                 52,300 
                 33.4 
                   
                 442 
                 0.174 
                 1.550 
               
               
                 37,515 
                 33.4 
                   
                 338 
                 0.002 
                 1.170 
               
               
                 38,289 
                 32.4 
                   
                 350 
                 0.041 
                 0.954 
               
               
                 41,012 
                 26.0 
                   
                 463 
                 0.040 
                 1.420 
               
               
                 35,700 
                 35.8 
                   
                 775 
                 0.013 
                 1.830 
               
               
                 22,097 
                 31.0 
                   
                 438 
                 0.020 
                 2.300 
               
               
                 45,597 
                 35.4 
                   
                 244 
                 0.442 
                 1.910 
               
               
                 59,081 
                 26.6 
                   
                   
                 1.340 
                 1.930 
               
               
                   
               
             
          
         
       
     
         [0037]    The plotted data shown in  FIG. 1 ,  FIG. 2 , and  FIG. 3  illustrate a significant and dramatic impact of the addition of the zeolite to a fixed film media reactor, either Trickling Filter or Rotating Biological Contactor with more effective surface area. 
         [0038]    An evaluation of the field data since the use of the zeolite addition has produced the following evaluation of the actual rock trickling filter performance vs. the model predictions employing standard design equations for nitrification performance. This evaluation again shows that there has been a dramatic increase in the surface area in the trickling filter. 
         [0000]    
       
         
               
             
               
               
               
               
             
               
               
               
               
             
               
               
             
           
               
                 TABLE 9 
               
             
             
               
                   
               
               
                 Mathematical Model vs. Field Data Comparison 
               
               
                 Trickling Filter Performance - Mathematical Model vs. Field Data 
               
               
                 (Standard Filter vs. Hybrid Media Processing) 
               
             
          
           
               
                 Name 
                 Value 
                 Unit 
                 Comment 
               
               
                   
               
             
          
           
               
                 EffTKNstd 
                 90.84 
                 mg/l 
                 Model Prediction Effluent TKN with standard 
               
               
                   
                   
                   
                 media 
               
               
                 EffTKNhybrid 
                 50.21 
                 mg/l 
                 Model Prediction Effluent TKN with hybrid 
               
               
                   
                   
                   
                 media 
               
               
                 Field Raw NH3 
                 71.98 
                 mg/l 
                 Measure Average Applied NH3 
               
               
                 Model Raw NH3 
                 81.40 
                 mg/l 
                 Model Applied NH3 
               
               
                 Field TF Eff NH3 
                 29.58 
                 mg/l 
                 Measure Average Hybrid Media Eff NH3 
               
               
                 EffNH3std 
                 72.80 
                 mg/l 
                 Model Prediction Effluent NH3 with standard 
               
               
                   
                   
                   
                 media 
               
               
                 EffNH3hybrid 
                 51.40 
                 mg/l 
                 Model Prediction Effluent NH3 with hybrid 
               
               
                   
                   
                   
                 media 
               
               
                 % NH3 Std Model 
                 10.6% 
                 % 
                 Projected % Removal by Model Standard 
               
               
                   
                   
                   
                 Trickling Filter 
               
               
                 % NH3 Field 
                 28.59% 
                 % 
                 Actual % Removal by Hybrid Media 
               
               
                   
                   
                   
                 Processing 
               
               
                 &amp; NH3 Std Model 
                 −1.14% 
                 % 
                 Predicted % Removal by Model for Std 
               
               
                   
                   
                   
                 Trickling Filter 
               
               
                 Model vs Field 
                 −73.7% 
                 % 
                 Correlation between Model vs. Field for 
               
               
                   
                   
                   
                 Hybrid Media Processing 
               
             
          
           
               
                 Effective Surface Area 
                 2.30 Zeolite Effective Area factor 
               
               
                 Nitrification Rate Model 
                 0.00012 lb-N/ft {circumflex over ( )} 2/day 
               
               
                 Equivalent Surface Area 
                 51.75 ft {circumflex over ( )} 2/ft {circumflex over ( )} 3 Equivalent Surface Area based on filter volume 
               
               
                 Nitrification Rate Field 
                 0.00027 lb-N/ft {circumflex over ( )} 2/day 
               
               
                 Data 
               
               
                 Equivalent Surface Area 
                 93,577 ft {circumflex over ( )} 2/ft {circumflex over ( )} 3 Equivalent Surface Area based on filter volume 
               
               
                 Field Data 
               
               
                   
               
             
          
         
       
     
         [0000]    
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 10 
               
             
             
               
                   
               
               
                 Field Performance Evaluation 
               
             
          
           
               
                   
                   
                 Primary 
                   
                   
                   
                   
               
               
                   
                   
                 Filter 
                 Primary 
                 Actual lb 
                   
                 % 
               
               
                   
                 Primary 
                 Nitrification 
                 filter 
                 NH3 
                   
                 Increase 
               
               
                   
                 filter % 
                 Rate lb 
                 Nitrification 
                 Removed 
                 Equivalent 
                 in 
               
               
                   
                 NH3 
                 N/day-Sq- 
                 Rate Field 
                 lb N/day- 
                 Surface 
                 Surface 
               
               
                   
                 Removed 
                 Ft 
                 Data 
                 Sq-Ft 
                 Area ft{circumflex over ( )}2 
                 Area 
               
               
                   
                   
               
             
          
           
               
                 Average 
                 44.18% 
                 0.00007 
                 0.00027 
                 7.83 
                 98,452 
                 355% 
               
               
                 Maximum 
                 85.33% 
                 0.00013 
                 0.00074 
                 15.74 
                 160,791 
                 581% 
               
               
                 Minimum 
                 3.85% 
                 0.00004 
                 −0.00005 
                 1.79 
                 34,549 
                 125% 
               
               
                 Std. Dev 
                 21.08% 
                 0.00002 
                 0.00020 
                 3.63 
                 43,297 
                 156% 
               
               
                   
               
             
          
         
       
     
         [0039]    Both Table 9 and Table 10 indicate that for the trickling filter to be performing as measured by actual field data indicates that a large increase in viable surface area in the trickling filter has been achieved by the addition of the zeolitic material. According to Table #10 it would appear that the nitrification rate has decreased. These values were in fact back calculated from the field data. The “Primary Filter Nitrification Rate” value was determined using Equation 1 whereas the “Primary Filter Nitrification Rate Field Data” employed the amount of nitrogen removed based on the surface area of the rock media. Therefore in order for the Trickling Filter to be removing the amount of nitrogen that was measured in the field there had to be an increase in the surface area and thus the values indicated in the “Equivalent Surface Area” as shown in Table 10. 
         [0040]    A particular Trickling Filter plant was experiencing wide variations in applied hydraulic and organic loadings due to seasonal activities e.g. weekend vs. weekday flows. Superimposed on top of these varying loads was the fact that it was for a rest stop facility on a major Turnpike with its related variations in flows due to varying use of the rest stop as well as wastewater characteristics. In addition, the rest stop generated wastewater that was high in ammonia and Chemical Oxygen Demand due to the use of low water use toilets with winter temperatures of the wastewater in the 4 to 5° C. (39.2 to 41.0° F.) range. The regulatory agency was taking actions due to the facility not meeting its NPDES permit requirements even after being retrofitted with an addition plastic media trickling filter complete with covers for the trickling filter and hot air ventilating/heating system. 
         [0041]    The raw waste exhibited ammonia nitrogen levels in the range of 50 to 135+ mg/l with Chemical Oxygen Demand (COD) levels as high as 900+ mg/l as well as temperatures of 4 Degrees C. Adjustment of the recirculation rates, sludge wasting and normal process adjustments for a trickling filter plant to address the reduction of these values was met with limited success. In addition, due to the wide swings in wastewater characteristics, swings in biofilm sloughing were incurred with the resulting decrease in the settleablilty of the sludge and subsequent loss process control. The plant also had problems meeting its ammonia requirements for a large portion of the year round. 
         [0042]    A Trickling Filter treatment plant comprised of an equalization tank, primary clarifier, two parallel rock trickling filters, a secondary plastic media trickling filter followed by a final clarifier and a disinfection system with the plant having a design capacity of 40,000 gallons per day. The Trickling Filter was out of compliance due to excessively high concentrations of COD and BOD, ammonia-nitrogen, low conversion of ammonia nitrogen, poor settling, low BOD5 removal and low temperatures. 
         [0043]    In a first part of the process of the present invention, Zeolite, obtained from Daleco Resources Corporation of West Chester, Pa., were employed at a dosage of 50 parts per million based on the average daily flow to the plant. It should be noted that the Trickling Filter process is preceded by both an Equalization Basin and Primary Clarifiers and has an internal recycle from the effluent from the Trickling Filter. The dosage is based on the raw sewage flow to the plant. Therefore each train of the Trickling Filter process was having 25 parts per million of zeolite being applied to it. 
         [0044]    The zeolitic material addition operated as a weighting agent, substrate and structural unit with large surface area per unit volume for bacterial growth to occur as well as an ion exchange site for ammonia. In wastewater treatment it is the culturing of assimilated bacteria to the wastewater composition that affects the treatment process performance. Employing a zeolitic material allowed more bacteria to grow and stay in the process longer to affect the treatment process performance, stability and operability. The design of Trickling Filters and attached growth treatment processes are based on the organic (BOD) loading rate per unit of surface area. The surface area is defined by the square feet of surface created by the specific media employed e.g. rock has 15 square feet per cubic foot of media volume while synthetic plastic media can be as much as 32 square feet per cubic foot of media volume. The amount of zeolite employed is based on the desired increase in surface area required in order to achieve the desired loading rates for either or both carbon and nitrogen based pollutants. 
         [0045]    In order for the zeolites to reach an effective level in the waste treatment process an optimum dose must be reached; in this case 30 to 60 parts per million, based on the daily flow to the plant. Additionally, since the bacteria must grow and create a culture on the zeolites material the zeolites effectiveness is directly related to the Retention Time in the treatment system. For a Trickling Filter or attached growth system the equivalent Retention Time would be based on the amount of sloughing that occurs of the biofilm that is attached to the media. In this instance a value of 5% was employed for the amount of biofilm sloughing that was taking place. The other consideration is the amount of zeolite that would be entrapped in the biofilm. It has been reported in the literature that 95% of a zeolite applied to a Trickling Filter plant is removed. This value was the basis for employing 5% as the amount of zeolite entrapped in the biofilm. In this application the daily flow of 6,000 gallons per day would be ((6,000*8.34*60)/1,000,000) or 3.0 pounds per day. The biofilm age (based on the sloughing rate) was 20 days and each reactor was receiving 3,000 gallons per day, each reactor would be receiving 1.5 pounds of material. On the first day 0.075 pounds of the zeolite would be retained in the biofilm. On day two there would be another 0.075 pounds of zeolite retained in the biofilm with a sloughing loss of 5%. After the first day 5% of the first day&#39;s 0.075 pounds of zeolite would be wasted. On the second day 5% of the 0.07125 pounds would be wasted along with 5% of the second day&#39;s 0.075 pounds. After two days there would be 0.139 pounds of zeolite enmeshed in the biofilm. At the end of 20 days there would be 1.425 pounds of zeolite in the biofilm on each trickling filter. 
         [0046]    If the average surface area for zeolites is 700 square meters per gram, (29,500 square feet per pound) then in the 20 day biofilm age example there would be 1.425 pounds of zeolites in the biofilm at a 5% biofilm enmeshment rate The effective growth area for bacterial growth that one would have is 2,213 square feet of surface area per day per trickling filter or at a biofilm age of 20 days over 44,250 square feet of surface area. The combined primary filters have a total surface area of 27,695 square feet using 15 square feet per cubic foot for the rock media. This amounts to a 159% increase in surface area if all the added zeolitic material was effective or a total surface area of 71,945 square feet. Actual field data at the plant indicated that the effective surface area of the added zeolite is 3.3% effective when the actual effective surface area is computed based on the performance of the rock filters. The higher the biofilm age the greater square feet of added effective surface area retained in the filter. This effectively increases the rock media from 15 to 47 square feet per cubic foot of surface area for each Trickling Filter. This has effectively increased the rock trickling filter to a plastic media trickling filter without the cost of retrofit. The effectiveness of increasing surface area for bacterial growth in wastewater treatment via numerous methods is well documented in the literature. Taking the amount of zeolitic material up to the steady state concentration has been employed; however, it still takes a number of biofilm ages for the zeolitic material in the reactor to develop the bacterial colonization. The 3.3% effective surface area takes into consideration sloughing loss and effective surface area for colonization. 
         [0047]    Using removal rates for BOD5 for the zeolitic material is equivalent to changing the media in the filter based on the additional media with a 3.0% effective surface area for the total amount of zeolitic material that is in the system at a steady state the BOD5 removal could be improved from approximately 30% to 80%+ as shown in the data. 
         [0048]    The cost effectiveness of the implementation of the use of this method of improving an attached growth e.g. trickling filter or rotating biological contactor plant employing different types of media including rock and plastic media would be the cost of the zeolite additive. Assuming an installed cost to replace the rock media in a 20,000 gallon per day trickling filter plant with high surface plastic media of $300 per cubic foot installed then the capital savings for the demonstration plant are $553,800 minus the ongoing going cost of the zeolite For this plant they are using 5 pounds per day. The cost for the zeolite is approximately $2.50 per day or $912 per year to get this performance enhancement vs. a cost of $553,800. 
         [0049]    As show in  FIG. 4A  through  FIG. 4D , the processes of the present invention can be applied at numerous locations in a trickling filter plant. As used in  FIG. 4A  through  FIG. 4D  the following abbreviations are used to describe the different pieces of equipment used in a typical trickling filter plant:
       Legend: (RS)—raw wastewater, (PC) primary clarifier, (PE) primary effluent, (TF INF ) trickling filter influent, (TF) trickling filter, (TF EFF ) trickling filter effluent, (TF RCY ) trickling filter recycle, (SC) secondary clarifier, (WS) waster sludge, (SE) secondary effluent, (IC) intermediate clarifier, (ICE)       
 
         [0051]    In place of a trickling filter, a sewage treatment process may employ rotating biological contactors growth or suspended attached growth, e.g. integrated fixed film activated sludge, or Moving Bed Biofilm Reactor systems. In that case the additions are also made to the wastewater stream. 
         [0052]    The foregoing detailed description provides illustrative embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Referring to the detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the invention.