Abstract:
A system for treating a fluid comprising solids and particulates where the system includes a separation device that includes a chamber having an outlet and an inlet, and a separation panel within the chamber that is in fluid communication with the inlet, where the separation panel includes a plurality of openings sized smaller than the solids and larger than the particulates. The separation panel also includes a plurality of deflectors to deflect the solids away from the separation panel while the fluid passes through the openings in the separation panel to remove the solids from the fluid. The system also includes a maturing area, in fluid communication with the separation device, to receive the fluid, where one or more additives are added to the fluid in the maturing area to create formed and enlarged particles from the particulates in the fluid, and where the formed and enlarged particles are removed from the fluid by the separation device.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit of U.S. Provisional Application No. 60/471,677 filed May 18, 2003, entitled “POTABLE WATER PRE-TREATMENT APPARATUS AND METHODS FOR USING THE SAME” the entire contents of which are herein incorporated by this reference. The application is also related to U.S. Pat. No. 5,788,848, issued Aug. 4, 1998, and U.S. Pat. No. 6,511,595, issued Jan. 28, 2003, both of which are entitled “APPARATUS AND METHODS FOR SEPARATING SOLIDS FROM FLOWING LIQUIDS OR GASES” and both of which are hereby incorporated by reference for all purposes, and the specific purposes described therein and herein. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The invention includes systems and methods to treat fluids containing solid contaminants including the separation of solids from the liquids and/or gases in the fluid. The invention also includes systems and methods for forming enlarged particles from smaller particulates in the fluid to separate the particles from the rest of the fluid. Fluids treated with the invention include, for example, raw water (e.g., waste water, storm water, etc.).  
         [0003]     Particulate contamination of fluids (i.e., liquids and gases) present environmental and public health challenges on several fronts: Particulates, such as dust and soot contained in gaseous effluents, are generated in a wide variety of industries such as power generation, and waste incineration, among others. These particulates are believed to contribute to respiratory health problems such as asthma. Thus, there continues to be need for technologies that remove solid particulates from gaseous effluents that are released into the air.  
         [0004]     Solid waste pollutants carried by water also present problems for the environment and public health. For example, stormwater being directed to waterways and seas is a major carrier of solid pollutants such as plastics, cans, tree branches, and animal feces, among other pollutants.  
         [0005]     There have been many endeavors to capture solid pollutants being carried by gases and liquids to limit their damage and make the fluids available for use (e.g., potable water). In the case of stormwater, one method for capturing solid pollutants has been to place grates across drain outlets. Unfortunately, the grates must have openings that are sufficient to allow the water to pass through them even when solid pollutants are trapped against the grate. Typically, the openings have to be so large that substantial numbers of solid pollutants escape with the water. Even when the grates have relatively large openings, it is often still necessary to provide flow paths around the grate and/or over the grate to prevent buildup of water upstream of the drain. Such systems are inadequate to capture small particulates that are several times smaller than the size of the grate openings. Thus, there remains a need for technologies that can remove solids having a wide range of sizes from stormwater while maintaining a high throughput of treated water.  
         [0006]     Solid waste pollutants carried by water also include human and animal waste transported by sewage systems. These systems often draw from the same water resources as municipal drinking water systems, whose capacities are increasingly stressed by human population growth. One way to reduce the competition for water resources between sewage and drinking water systems, is to convert waste water from the sewage systems into potable water for the drinking systems. Thus, there remains a need to develop systems and methods for waste water treatment that include the removal of solid wastes having a wide range of sizes in a high throughput, cost effective manner. These and other challenges facing the removal of solid pollutants from fluid streams are addressed by the present invention.  
       BRIEF SUMMARY OF THE INVENTION  
       [0007]     Embodiments of the invention include a system for treating a fluid that includes solids and particulates. The system includes a separation device that includes a chamber having an outlet and an inlet, and a separation panel within the chamber that is in fluid communication with the inlet. The separation panel includes a plurality of openings sized smaller than the solids and larger than the particulates. The separation panel also includes a plurality of deflectors to deflect the solids away from the separation panel while the fluid passes through the openings in the separation panel to remove the solids from the fluid. The system also includes a maturing area, in fluid communication with the separation device, to receive the fluid, where one or more additives are added to the fluid in the maturing area to create formed and enlarged particles from the particulates in the fluid. The formed and enlarged particles are removed from the fluid by the separation device.  
         [0008]     Embodiments of the invention also include a system for producing pre-treated water from raw water containing solids for producing potable or municipal water. The system includes a separation device for separating particulates from said raw water. The separation device includes a chamber having an outlet and an inlet, and a separation panel within the chamber and in fluid communication with the inlet. The separation panel defines a separation chamber within the chamber, where the separation panel includes a plurality of openings, the openings being sized smaller than said particulates. The separation panel also includes a plurality of deflectors, where the deflectors deflect the particulates away from the separation panel while permitting said fluid to pass through the openings to separate the particulates from the fluid. The separation device also includes a washer for washing said particulates from the separation panel, where the washer is in fluid communication with a washing fluid source to supply the washer with washing fluid. The washer has one or more nozzles for directing the washing fluid towards the separation panel to wash the particles from the separation panel. When the washer directs the washing fluid towards the separation panel, one or more of the particles is washed from the separation panel. The system also includes a maturing area for receiving the raw water input and adding and mixing with the raw water one or more additives to induce, over a period of time, particle formation or enlargement of the solids in the raw water to produce matured raw water. The maturing area retains the raw water for a selected period of time to produce matured raw water, where the maturing area is in fluid communication with the separation device. When raw water enters the maturing area, the one or more additives is added to produce the formed or enlarged particles, and the separation device removes the formed or enlarged particles from the matured raw water to produce pre-treated water.  
         [0009]     Embodiments of the invention also include a method for pre-treating raw water containing solids for producing potable or municipal water. The method includes the step of providing a maturing area for receiving the raw water input and adding and mixing with the raw water one or more additives to induce, over a period of time, particle formation or enlargement of said solids in the raw water to produce matured raw water. The maturing area retains the raw water for a selected period of time to produce matured raw water. The maturing area is in fluid communication with the separation device, and when raw water enters the maturing area, the one or more additives is added to the raw water to induce the formation or enlargement of solids. The method also includes the step of providing a separation device for separating the formed or enlarged solids from the matured water. The separation device includes a chamber having an outlet and an inlet, the chamber being in fluid communication with the maturing area. The separation device also includes a separation panel within the chamber and in fluid communication with the inlet, the separation panel defining a separation chamber within the chamber. The separation panel includes a plurality of openings, where the openings are sized smaller than the formed or enlarged solids. The separation panel also includes a plurality of deflectors, where the deflectors deflect the formed or enlarged solids away from the separation panel while permitting the fluid through the openings to separate the formed or enlarged solids from the fluid. The method also includes the step of introducing the raw water into the maturation area, where the raw water matures to become matured water in which formed or enlarged solids are suspended. The method also includes passing the matured water to the separation device, where the separation device separates some or substantially all of the formed or enlarged solids from the matured water to produce pre-treated water for producing municipal or potable water.  
         [0010]     Additional features are set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following specification or may be learned by the practice of the invention. The features and advantages of the invention may be realized and attained by means of the instrumentalities, combinations, and methods particularly pointed out in the appended claims. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]      FIG. 1A  shows a continuous deflection separation unit according to embodiments of the invention;  
         [0012]      FIG. 1B  shows a close-up view of a segment of a separation panel used to entrain particles in a fluid flow path according to embodiments of the invention;  
         [0013]     FIGS.  2 A-G show a screen washing system according to embodiments of the invention;  
         [0014]      FIG. 3  shows a treatment state of a continuous flow system with additive/maturing tanks in-line with the continuous deflection separation unit according to embodiments of the invention; and  
         [0015]      FIG. 4  shows a screen-washing mode of the continuous flow system according to embodiments of the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0016]      FIG. 1A  shows a plan view of an embodiment of a continuous deflection separation device, which is useful in separating solids from a flowing fluid such as water. The continuous deflection separation device  180 , includes a separation panel  205 , which is preferably circular in shape in cross-section and having first and second open-ends. Separation device  180  is located within chamber  209  defined by outer chamber wall  207 .  
         [0017]     Exemplary separation panels may be formed from materials generally known as expanded metal or non-metal meshes, or formed by molding or punching similarly shaped panels having the features described herein. Fluid enters continuous deflection separation device  180  via an inlet  220 , in the direction of arrow  190 , wherein the inlet curves into chamber  210 . Water and entrained particles are presented through inlet  220  into separation chamber  210 , which is defined by separation panel  205 , wherein the generally cylindrical configuration of separation panel  205  imparts a circular flow to the fluid within the confines of separation chamber  209 , in the direction shown by arrow  203 . As the fluid flows across the surface of separation panel  205 , particles  101  are deflected in towards the center of separation chamber  210 , whereas the fluid carrying the particles  101  can flow in direction  103  through separation panel  205  into chamber  209  and out outlet  230  along the path indicated by arrow  200 .  
         [0018]     The resulting arrangement causes an accumulation of particles within the separation chamber as fluid flows through device  180 , thus retaining some or all of the particles introduced into device  180  through inlet  220 . At some point, it may be desired to remove accumulated particles by aspiration or draining of contents of separation chamber  210 , as will be discussed further below. Fluid pressure at inlet  220  may be created by gravity flow, or by pumping fluid into device  180 , or by withdrawing fluid from outlet  230 .  
         [0019]      FIG. 1B  depicts an exemplary separation panel  205 , which comprises a plurality of deflectors  205   a  that are generally presented with their closed face to the direction of flow of the liquid as shown by arrow  104  along separation panel  205  within separation chamber  210 . Behind each deflector  205   a  is opening  103  disposed at an angle to the direction of flow (arrow  104 ). Preferably, openings  103  are all of a predetermined size that generally restricts the passage of particles to be separated from the fluid, whereas the fluid is able to pass through openings  103 . Thus, only the fluid, and particles of a size substantially smaller than that of openings  103  are generally able to pass through separation panel  205 .  
         [0020]     In general, particles larger in size than opening  103  are trapped within the confines of the separation chamber for removal from separation chamber  210 , as described below. Circular motion (as depicted by arrow  203 ) of the fluid within separation chamber  210  facilitates the trapping of particles by continuously deflecting the particles into the center of separation chamber  210 , away from separation panel  205 , thus making separation panel  205  substantially self-cleaning when in use. Particles trapped within separation chamber  210  may continue moving by the circular flow, as depicted by arrow  203 , until they settle under gravity. Floatable particles may be retained on the surface, or accumulate in a suspension to the extent that the fluidic nature of the fluid changes. For example, the effective viscosity of the fluid may prevent its passage through openings  103  at a rate to cause sufficient overall flow through device  180  at a rate to sustain circular motion of the fluid as depicted by arrow  203 . Meanwhile, particles and fluid able to pass through openings  103  may exit device  180  through outlet  230 .  
         [0021]      FIG. 1A  depicts an embodiment where the flow of the fluid outside separation chamber  210  is in a direction opposite of that within separation chamber  210 . Not wishing to be bound by theory, this counter-current flow motion on opposite sides of separation panel  205  is believed to establish a kinetic equilibrium which in turn facilitates the self-cleaning nature of the circular flow motion established within the separation chamber as depicted by arrow  203 . In other embodiments, the flow outside of separation chamber  210  may be in the same direction as the flow within separation chamber  210 .  
         [0022]      FIG. 2E  depicts an embodiment where device  180  may also include sump  187  for the containment (and removal, if desired) of settleable particles. Sump  187  may be designed so as cause a slowing down of the circular flow of the liquid at the lower sump portion  187   b , so as to facilitate settlement of particles. Sump  187  may also include an outlet  360   a  and outlet valve  187   a  to permit occasional removal of settled particles by gravity or pumped flow, and could further include, for example, further concentration of the settled particles into a screening bucket (not shown). Floating particles, or particles that do not settle, may be removed by skimming, or draining. Draining the particles may be accompanied by a washing step caused by a separation panel washer, such as shown in FIGS.  2 A-D.  
         [0023]     FIGS.  2 A-D show different views of two different types of elements that can be used to assist in the cleaning of separation panel  205  and facilitate the movement of particles out of separation chamber  210  via sump outlet  360 .  FIG. 2A  shows a plan-view of an arm type washer element  370 , where washing fluid is passed through washer element  370  to emanate from one or more nozzles located along arm portion  370   b , which direct washing fluid against inner side  205   a  of separation panel  205  to cause particles to wash off inner side  205   a  in a downward direction as depicted by arrow  378  as shown in  FIG. 2B .  FIG. 2A  shows washing element  370  rotating about the center axis of separation chamber  210  to move the nozzles across inner side  205   a  of separation panel  205  as shown in  FIG. 2D .  
         [0024]     In another embodiment,  FIG. 2C  shows washer element  370  comprising a ring or arc structure that provides for one or more nozzles for directing washing fluid against inner side  205   a  of separation panel  205  for washing particles. The ring, as shown in  FIG. 2D , or arc structure of washing element  370  is moved up and down the center axis of the cylinder  5  formed by separation panel  205  to move the nozzles along inner side  205   a  of separation panel  205  to cause the particles to move towards sump outlet  360 .  
         [0025]      FIG. 2E  shows an embodiment where sump  187  further comprises flange  371  for assisting the settlement of particles into sump  187 . Flange  371  may be a downwardly directed annular flange or baffle that assists in directing downwardly moving solids into sump  187 . Flange  371  may also substantially prevent the circular motion of the fluid within the upper regions of the separation chamber from being transferred into the sump  187 .  
         [0026]      FIG. 2F  shows an embodiment where a shower head  275  is used to direct liquid against the separator panel to wash material away.  FIG. 2G  shows another embodiment of a shower head  277  used to direct a liquid against the separator to wash material away.  
         [0027]     Where more purified fluids are required at the conclusion of the filtration procedure, it is possible for the outlet from a first device according to the invention to feed into the inlet for a second device, and therefore, for the fluid to be filtered sequentially by two or more such devices, arranged in series. In such an arrangement, the size of the openings in the separation panels for the second and subsequent separators could be sequentially (and increasingly) smaller, so that each subsequent separator removes increasingly finer particles. Hence, by this arrangement, very high, or indeed, any desired level of filtration or purification could be achieved. Alternatively, for high-throughput filtration, two or more devices may be banked in parallel to provide higher throughput than a single unit.  
         [0028]     While much of the foregoing description of the embodiments has been concerned with apparatus for separating particles entrained in liquids it is to be understood that the invention may also be used for the separation of solids entrained in gases. Operation of gas/solid separators constructed in accordance with embodiments of the invention, may include a sealed unit separator that slows or prevents the undesired escape of gases undergoing filtration. Sealing the unit may also be utilized in liquid/solid separators constructed in accordance with the present invention. In this way, solid matter entrained in exhaust gases and gaseous emissions from various manufacturing plants may be filtered in much the same way as solid-bearing liquids are treated according to embodiments of apparatuses and methods of the present invention.  
         [0029]      FIG. 3  shows an embodiment of an apparatus that utilizes the separation device  180  described above. In  FIG. 3 , device  180  is situated downstream from one or more additive sources, such as additive sources  290 ,  300 ,  310 , and  320 , for providing, for example, a flocculent or polymer additive, used to form or enlarge particles in a fluid-particle suspension for later separation by device  180 . The addition of additives from additive sources, such as  290 ,  300 ,  310 , and  320  may be regulated by valves and/or pumps such as valve/pumps  290   a ,  300   a ,  310   a , and  320   a . Additive sources may further feed into one or more maturing tanks in serial fluid communication, such as maturing tanks  130 ,  140 ,  150 , and  160 , and each tank may also have an impeller  170  for mixing the contents of each tank. Additive sources and maturing tanks may collectively be referred to as maturation area  110 .  
         [0030]     Each of the additive sources may be under the global control of controller panel  270 , which may be under the direction of computer unit  280 . Controller panel  270  and/or computer unit  280  may further be in communication with inlet control valve/pump  320  and/or outlet control valve/pump  330  for regulating flow of fluid from maturation area  110  through device  180  and onto optional storage tank  260 , which serves to store treated, or pre-treated fluid (if downstream processing is to occur).  
         [0031]     One of ordinary skill in the art would realize that other configurations of pumps and valves may be utilized to regulate the flow of fluids through device  180 . Treated fluid from storage tank  240  may optionally be tapped to supply washing element  370  during a separation panel washing cycle. Valves  370   a  and  360   a  may also be controlled by controller panel to empty sump  187  and wash separation panel  205  during a separation panel wash cycle.  
         [0032]      FIG. 4  shows the apparatus illustrated in  FIG. 3  operating in a separation panel washing mode, where valves  320  and  330  close to stop flow of fluid through the separation device  180 , and where valve  360  opens to drain fluid from separation device  180  through drain pipe  360 . In addition, valve or pump  370   a  opens to flow washing fluid through washing arm  370  to apply washing fluid against separation panel  210  to cause accumulated material to be washed down and drained through drain pipe  360 .  
         [0033]     After a selected period of time washing, valve or pump  370   a  closes or stops the flow of washing fluid flowing through washing arm  370 , and drain valve  360  closes. With separation device  180  in a clean state, the apparatus is now ready to continue operation by opening valves  320  and  330  to once again establish flow through separation device  180 . During the separation panel washing mode, fluid coming into the apparatus accumulated within the maturing area  110 . Furthermore, fluid to wash separation panel  210  may be derived from holding tank  240  through a fluid connection (not shown) with valve or pump  370   a.    
       EXAMPLES  
       [0034]     Potable water pre-treatment systems according to embodiments of the invention were used to treat raw water in three different locations. The systems could treat about 3 to about 5 liters/second (i.e., about 70,000 to about 115,000 gallons per day) of raw surface water as pretreatment for drinking water use. Tables 1-3 show operating conditions for each location were the systems were tested:  
                                                             TABLE 1                       Operating Conditions for Pretreatment of River Water in       Western Pennsylvania:                                Location   Western Pennsylvania       Water Source   River       Season of Year   Fall            Coagulant Type   Poly-Aluminum Chloride   Poly-Aluminum Chloride       Coagulant dose   30 mg/l   30 mg/l       (mg/l)       Flocculant Type   Anionic, high Molecular   Cationic, high Molecular           Weight, medium CD   Weight, medium CD       Folcculant Dose    1 mg/l    1 mg/l       (mg/l)            Turbidity In/Out   25-230 NTU   0.8-2.5 NTU   25-60 NTU   1-2 NTU                  
 
         [0035]    
       
         
               
             
               
               
             
               
               
               
             
           
               
                 TABLE 2 
               
               
                   
               
               
                   
               
               
                 Operating Conditions for Pre-treatment of Reservoir Water in 
               
               
                 Western Pennsylvania 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Location 
                 Western Pennsylvania 
               
               
                 Water Source 
                 Reservoir 
               
               
                 Season of Year 
                 Summer 
               
               
                 Coagulant Type 
                 Poly-Aluminum Chloride 
               
               
                 Coagulant dose (mg/l) 
                 30 mg/l 
               
               
                 Flocculant Type 
                 Anionic, high Molecular Weight, medium CD 
               
               
                 Folcculant Dose (mg/l) 
                  1 mg/l 
               
             
          
           
               
                 Turbidity In/Out 
                 1-1.5 NTU 
                 0.4-0.6 NTU 
               
               
                   
               
             
          
         
       
     
         [0036]    
       
         
               
             
               
               
             
               
               
               
             
               
               
               
               
               
             
           
               
                 TABLE 3 
               
               
                   
               
               
                   
               
               
                 Operating Conditions for Pretreatment of River Water in West Virginia: 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 Location 
                 West Virginia 
               
               
                 Water Source 
                 River 
               
               
                 Season of Year 
                 Spring 
               
             
          
           
               
                 Coagulant Type 
                 Ferric Chloride 
                 Poly-Aluminum Chloride 
               
               
                 Coagulant dose 
                 30 mg/l 
                 40 mg/l 
               
               
                 (mg/l) 
               
               
                 Flocculant Type 
                 Cationic, high Molecular 
                 Anionic, high Molecular 
               
               
                   
                 Weight, medium CD 
                 Weight, medium CD 
               
               
                 Folcculant Dose 
                  1 mg/l 
                  1 mg/l 
               
               
                 (mg/l) 
               
             
          
           
               
                 Turbidity In/Out 
                 72-86 NTU 
                 1.8 NTU 
                 50-62 NTU 
                 2-5 NTU 
               
               
                   
               
             
          
         
       
     
         [0037]     Performance of this demonstration unit has been as good or better as the performance of full-scale conventional-technology water pre-treatment facilities. The continuous deflective separation systems described herein may also be designed with scale-up methods for facilities of varying capacity. These scale-up methods can be used to design drinking water pre-treatment facilities of larger capacities as well.  
         [0038]     Those skilled in the art will readily appreciate that the apparatus and methods of the present invention are capable of being put to many different uses, and that they embrace many modifications and variations. It should be understood that the spirit and scope of the present invention is in no way limited to the particular details of the embodiments described herein, but also extends to, and is determined by, reference to the features described by the appended claims.  
         [0039]     Also, the words “comprise,” “comprising,” “include,” “including,” and “includes” when used in this specification and in the following claims are intended to specify the presence of stated features, integers, components, or steps, but they do not preclude the presence or addition of one or more other features, integers, components, steps or groups.