Abstract:
A fluid processing system and method of processing a fluid includes a tank having an outer wall, a heating element, and an insulating element. The heating element is situated within the tank and includes a first electrode and a second electrode. The insulating element is positioned between the first electrode and the second electrode. As such, powering the heating element directs an electric current through the fluid within the tank for heating the fluid, while the insulating element provides electrical and thermal insulation to the outer wall of the tank.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates generally to a wet electrostatic precipitator and method of treating an exhaust, and more particularly, to a plurality of sieves for treating an exhaust. 
       BACKGROUND 
       [0002]    Traditional electrostatic precipitators and scrubbers are widely used for treating an exhaust containing gaseous pollutants and/or particulate emissions. For example, industrial processes, such as power and heat generation, may generate environmentally harmful particulate and gaseous emissions that may remain suspended in the air. These emissions often present health hazards when inhaled by humans and animals. Also, the particulate emissions tend to settle on equipment and buildings and may cause discoloration or even interfere with the proper function of the equipment. As such, it is important to remove these particulate emissions from the exhaust. 
         [0003]    In addition, the exhaust may be further treated by a traditional heat exchanger for recovering thermal energy from the exhaust. After all, many industrial processes discharge exhaust into the environment at an elevated temperature and recovering this thermal energy provides for an opportunity to improve the efficiency of the industrial process. Industrial processes capable of discharging exhaust containing gaseous pollutants at an elevated temperature may also be fitted with scrubber and/or a wet electrostatic precipitator (“wet ESP”) to both remove gaseous pollutants, such as particulate emissions, and recover thermal energy. Wet electrostatic precipitators typically include a liquid, such as water, to capture both particulate and gaseous emissions as well as thermal energy, which may be directed through a heat exchanger for improved efficiency. 
         [0004]    While electrostatic precipitators, scrubbers, and heat exchangers are generally known for use with industrial processes, the effectiveness of treating the exhaust has been limited, at least to some extent, by traditional design limitations and the wide variety of different components necessary for treatment. For example, electrostatic precipitators, scrubbers, and heat exchangers configured for treating exhaust typically require unique alloys and coatings that increase overall cost and limit available space. Thus, the amount of surface area available to any one of the precipitators, scrubbers, and heat exchangers is reduced and, similarly, reduces the effectiveness of the treatment. In addition, traditional wet electrostatic precipitators often produce a liquid mist that increases the likelihood of electrically shorting one or more electrodes, which also reduces its effectiveness for collecting particulate emissions. 
         [0005]    There is a need for an electrostatic precipitator and method of treating an exhaust that improves treatment effectiveness, reduces complexity, reduces costs, and addresses present challenges and characteristics such as those discussed above. 
       SUMMARY 
       [0006]    An exemplary embodiment of a wet electrostatic precipitator for reducing particulate emissions from an exhaust includes a flow chamber, which defines a flow path, and a plurality of sieves. The plurality of sieves are positioned within the flow chamber and arranged relative to each other to define a plurality of gaps for receiving the exhaust. Each of the sieves includes a liquid permeable material extending therealong. The liquid permeable material is configured to receive a liquid such that the liquid flows along the liquid permeable material for treating the exhaust. 
         [0007]    In one aspect of an exemplary embodiment of the wet electrostatic precipitator, each of the plurality of sieves includes an inlet for receiving the liquid and an outlet for discharging the liquid. Thus, a liquid collector is positioned proximate to the outlet of each of the plurality of sieves to collect the liquid. The wet electrostatic precipitator also includes a heat exchanger fluidly connected to the liquid collector. The heat exchanger is configured to receive the liquid from the liquid collector after having been heated by the exhaust to recover a thermal energy therefrom. 
         [0008]    In another aspect of an exemplary embodiment of the wet electrostatic precipitator, each of the plurality of sieves includes an inlet for receiving the liquid and an outlet for discharging the liquid. Thus, a liquid collector is positioned proximate to the outlet of each of the plurality of sieves to collect the liquid. Also, the plurality of sieves are configured to generate a condensate from the exhaust such that the liquid and the condensate flow together into the liquid collector. The wet electrostatic precipitator further includes a pump fluidly connected to the liquid collector and the inlet such that the pump directs the liquid and the condensate from the liquid collector to the inlet for reuse. 
         [0009]    Yet another aspect of an exemplary embodiment of the wet electrostatic precipitator has the plurality of sieves being electrically grounded. The wet electrostatic precipitator also includes a plurality of discharge electrodes positioned proximate to the plurality of sieves and electrically connected to a current supply. As such, the plurality of discharge electrodes charges a plurality of particulates with a plurality of charged particles flowing with the exhaust. In turn, the charged plurality of particulates accumulates on the plurality of sieves. 
         [0010]    An exemplary embodiment of a sieve assembly for treating an exhaust includes a plurality of sieves. The plurality of sieves is arranged relative to each other to define a plurality of gaps therebetween for receiving the exhaust. Each of the sieves includes a liquid permeable material extending therealong. The liquid permeable material is configured to receive a liquid such that the liquid flows along the liquid permeable material for treating the exhaust. 
         [0011]    In one aspect of an exemplary embodiment of the sieve assembly, each of the sieves includes a liquid permeable material defining a sleeve such that at least a portion of the sleeve is hollow. In another aspect of an exemplary embodiment, each of the sieves includes a core, and the liquid permeable material generally surrounds at least a portion of the core. Thereby, the core supports the liquid permeable material. In yet another aspect of an exemplary embodiment, the liquid permeable material is in the form of elongated cordage. 
         [0012]    In use, a method of treating an exhaust with the plurality of sieves includes directing the exhaust toward the plurality of sieves and flowing the liquid to the liquid permeable material. The method also includes absorbing the liquid within the liquid permeable material and permeating the fluid along the liquid permeable material such that the liquid flows therealong. Furthermore, the method includes impacting the exhaust against the liquid flowing along the liquid permeable material in order to treat the exhaust. 
         [0013]    Various additional objectives, advantages, and features of the invention will be appreciated from a review of the following detailed description of the illustrative embodiments taken in conjunction with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below serve to explain the invention. 
           [0015]      FIG. 1  is a schematic cross-sectional view of a first exemplary embodiment of a wet electrostatic precipitator. 
           [0016]      FIG. 2  is a perspective view of a second exemplary embodiment of a wet electrostatic precipitator. 
           [0017]      FIG. 3  is an enlarged perspective view of a sieve assembly of the wet electrostatic precipitator of  FIG. 2 . 
           [0018]      FIG. 4  is a cross-sectional view of the sieve assembly taken along section line  4 - 4  of  FIG. 3 . 
           [0019]      FIG. 5A  is a cross-sectional view of the sieve assembly taken along section line  5 A- 5 A of  FIG. 3 . 
           [0020]      FIG. 5B  is a cross-sectional view similar to  FIG. 5A , but showing another embodiment of a sieve assembly. 
           [0021]      FIG. 5C  is a cross-section view similar to  FIG. 5A , but showing yet another embodiment of a sieve assembly. 
           [0022]      FIG. 5D  is a cross-section view similar to  FIG. 5A , but showing still another embodiment of a sieve assembly. 
           [0023]      FIG. 5E  is a cross-section view similar to  FIG. 5A  but showing still another embodiment of the sieve assembly. 
           [0024]      FIG. 6  is an exemplary embodiment of a woven liquid permeable material. 
           [0025]      FIG. 7  is a perspective view of a third exemplary embodiment of a wet electrostatic precipitator. 
           [0026]      FIG. 8  is a cross-sectional view of the wet electrostatic precipitator taken along section line  8 - 8  of  FIG. 7 . 
           [0027]      FIG. 9  is a diagrammatic depiction of a sieve assembly for use in the present invention. 
           [0028]      FIG. 10  is an isometric view of a water delivery system for use in the present invention. 
           [0029]      FIG. 11  is a schematic cross-sectional view of an electrostatic precipitator according to the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0030]    With reference to  FIG. 1 , a first exemplary embodiment of a wet electrostatic precipitator  10  includes a duct  12  having a flow chamber  14  and a sieve assembly  16 . The sieve assembly  16  is positioned within the flow chamber  14  to define a flow path  18  therethrough. The sieve assembly  16  is arranged within the flow chamber  14  to coordinate a three stage method of treating an exhaust flowing through the duct  12  from a duct inlet  20  toward a duct outlet  22 . According to the exemplary embodiment, the exhaust has excess thermal energy and a plurality of particulate and gaseous emissions, both of which may be removed and recovered from the exhaust during treatment. The sieve assembly  16  includes a plurality of sieves  24 . Each of the sieves  24  includes a liquid permeable material  26  that partially obstructs the exhaust flowing along the flow path  18 . The plurality of sieves  24  also defines a plurality of gaps  28  therebetween for receiving the exhaust flowing from the duct inlet  20  to the duct outlet  22 . Furthermore, each of the sieves  24  is configured to receive a liquid, such as water or an alkali solution so that the liquid flows, by gravity and/or capillary action, along the liquid permeable material  26 . Thereby, the plurality of particulate and gaseous emissions (e.g., NO x , SO x , CO 2 , and Mercury) and excess thermal energy passing through the duct  12  accumulates within the liquid for treating the exhaust, which may then be discharged to the environment. According to the exemplary embodiment, the plurality of sieves  24  recovers particulate emissions, gaseous emissions, and thermal energy from the exhaust. However, it will be appreciated that the any number of sieves  24  may be used in any number of arrangements and dedicated to scrubbing and/or recovery and removal of either one or both of the emissions or thermal energy. As such, the term “treatment” is not intended to limit the invention described herein. 
         [0031]    A first stage of treatment includes a first portion  30  of the sieve assembly  16  positioned proximate to the duct inlet  20 . As such, the first stage of treatment is upstream of a second stage and a third stage of treatment, which includes second and third portions  32 ,  34  of the sieve assembly  16 , respectively. The first stage of treatment includes the first portion  30  of the sieve assembly  16  configured to remove the plurality of particulate emissions from the exhaust via impaction and act as a scrubber, while also removing thermal energy from the exhaust. In contrast, the second stage of treatment includes the second portion  32  of the sieve assembly  16 , which is electrically grounded, and a plurality of discharge electrodes  36  positioned proximate to the sieve assembly  16 . The plurality of discharge electrodes  36  is configured to generate negatively-charged particles that attach to the particulate emissions within the exhaust. In turn, the second portion  32  of the sieve assembly  16  attracts the negatively-charged particulate emissions, which then accumulate thereon for removal from the exhaust. Finally, in the third stage of treatment, the third portion  34  of the plurality of sieves  24  repeats the first stage of treatment for a final recovery of particulate emissions and thermal energy. Notably, any liquid and condensate that may form on the sieve assembly  16  may be recycled and reused for future treatment of additional exhaust as discussed below in greater detail. 
         [0032]    With respect to the plurality of discharge electrodes  36 , it will be appreciated that the particulate emissions are generally given a negative electrical charge by passing these particulate emissions through a region in which gaseous ions flow (i.e., a corona). More specifically, an electrical field forms between the discharge electrodes  36  and the grounded liquid permeable material  26 , which is conductive due to the liquid flowing therealong. Each of the discharge electrodes  36  is operatively connected to an electrical current supply in order to maintain a high voltage between the discharge electrodes  36  and the liquid permeable material  26 , which acts as a collection electrode. Thus, it will be appreciated that the wet electrostatic precipitator  10  further includes electrical equipment for generating a high-voltage supply, such as a high-voltage transformer and a rectifier. These and other components may be operatively connected to the discharge electrodes  36  and liquid permeable material  26  as is presently understood in the state of the art. Alternatively, each of the sieves  24  may further include a collection electrode, such as the frame member  52 , (See  FIG. 3 ) positioned proximate to the permeable material, which may be electrically grounded for attracting the negatively charged particulate emissions. In addition, a metal wire may be integrated into the sieves  24  for improved conductivity and grounding. It will be further appreciated that the corona may be positively or negatively charged and, in this respect, any charge may be used in accordance with the invention described herein. As such, the invention is not intended to be limited only to the negative charges discussed above. 
         [0033]      FIGS. 2-5A  show a second exemplary embodiment of a wet electrostatic precipitator  110  (no discharge electrodes are shown) having the first portion  30  of the plurality of sieves  24 . As discussed briefly above, the plurality of sieves  24  are arranged to define the plurality of gaps  28  through which the exhaust flows from a duct inlet  120  to a duct outlet  122  with like numbers indicating like features discussed above. According to the exemplary embodiment, the liquid permeable material  26  defines a sleeve  37  and is between approximately 1 millimeter and approximately 2 millimeters thick. As such, many, if not all, of the gaps  28  are less than approximately one inch. More particularly, the gaps  28  are between approximately two millimeters and approximately 5 millimeters. According to the exemplary embodiment, at least a portion of the sleeve  37  is hollow and, more particularly, the sleeve  37  is generally hollow. However, it will be appreciated that thinner sleeves  37  have more surface area per volume than thicker sleeves  37 . Therefore, a desirable number of sieves  24  and the geometry of the sleeves  37  may be optimized for improved performance, such as ESP collection efficiency, pressure drop, production cost, etc. 
         [0034]    The first portion  30  of the sieve assembly  16  includes first, second, and third sieve arrangements  38 ,  40 ,  42  of seven, eight, and seven sieves  24 , respectively. The exemplary embodiment, each of the sieve arrangements  38 ,  40 ,  42 , includes sieves  24  offset and parallel from each other along a linear row. Notably, the plurality of sieves  24  are oriented generally vertically and, as such, perpendicular to the flow direction of the exhaust. While the sieves  24  are distributed about the flow chamber  14  generally evenly to define like gaps  28 , it will be appreciated that more or less sieves  24  may be used with varying orientation and placement within the duct  12 . 
         [0035]    With respect to  FIG. 2  and  FIG. 3 , each sieve arrangement  38 ,  40 ,  42  includes the generally horizontally extending support member  44 , which defines a liquid supply conduit  46  extending therethrough. Furthermore, an elongate slot  48  extends longitudinally along a length of the support member  44 . The slot  48  extends through the support member  44 , into the liquid supply conduit  46 , and is configured to receive the liquid permeable material  26  of the sieve  24  and fasten therein. Thereby, the support member  44  supports the generally vertical orientation of the sleeve  37  of the liquid permeable material  26 , while the slot  48  further defines a sieve inlet  50  through which liquid is introduced into liquid permeable material  26 . Alternatively, the sieve inlet  50  may further include a tube  51  extending from and in fluid communication with the liquid supply conduit  46  to the remainder of the sieve  24 . According to the exemplary embodiment, the support member  44  and the liquid supply conduit  46  are in the collective form of a single elongate tube; however, it will be appreciated that another structure for supporting the sieves  24  and providing for the supply of liquid to the sieve inlet  50  may be so used. 
         [0036]    While the sieves  24  include the sleeve  37  of liquid permeable material  26  supported by the support member  44 , the exemplary embodiment further includes a frame member  52  extending therealong to further support the liquid permeable material  26 . Specifically, the liquid permeable material  26  for each of the sieves  24  of the respective sieve arrangements  38 ,  40 ,  42  joins together as a single, unitary inlet end of liquid permeable material  26 , which is fastened to the support member  44  within the slot  48 . The liquid permeable material  26  extends from the slot  48  and away from the support member  44  toward the frame member  52 . At each of the sieves  24 , the liquid permeable material  26  envelops the frame member  52 . In turn, the liquid permeable material  26  extends along the frame member  52  such that the frame member  52  supports the liquid permeable material  26  against the exhaust flow. The liquid permeable material  26  and the frame member  52  further extend away from the support member  44  to a sieve outlet  54 . According to the exemplary embodiment, the sieve inlet and outlet  50 ,  54  are opposing end portions of the liquid permeable material  26 . However, it will be appreciated that the sieve inlet and outlet  50 ,  54  may alternatively include or additionally include further structures, which may define, respectively, the inlet and outlet. 
         [0037]      FIG. 4  and  FIG. 5A  show the sleeve  37  of liquid permeable material  26  wrapped around the frame member  52  for supporting the liquid permeable material  26  against the flow of the exhaust. Notably, the liquid permeable material  26  has a length in the direction of the exhaust flow that is greater than its width for reducing drag while increasing an amount of available surface area, which contacts the exhaust. Thus, the increased surface area provides for more contact with the liquid flowing along the liquid permeable material  26  to remove and recover more particulate emissions and thermal energy. According to the exemplary embodiment, the liquid permeable material  26  is a thermoplastic material formed from a fibrous felt mat, such as a polypropylene fibrous felt mat, which resists various alkali and acids. However, other liquid permeable materials configured for providing for the flow of liquid exposed to the exhaust may be similarly used. For example, polypropylene sulfide (“PPS”) material and/or polyether ether ketone (“PEEK”) material may alternatively be used to accommodate a greater range of exhaust temperatures, such as relatively high exhaust temperatures. 
         [0038]    According to the exemplary embodiment, the frame member  52  is in the form of a rigid rod and the sleeve  37  wraps loosely around the frame member  52 . However, it will be appreciated the rod may alternatively be semi-rigid or even flexible. Alternatively, the frame member  52  may be a hollow tubular support configured to provide for a supply of liquid at a desirable pressure into the sleeve  37 . Such a hollow tubular support may provide for improved flushing and removal of particulate deposits from holes therein and/or improved scrubbing of gaseous emissions. By way of example,  FIG. 5B  shows another exemplary embodiment of a frame member  152  in the form of a hollow rod, which itself is supported by a flexible cable  154 , such as a rope. In this respect it will be appreciated that alternative frame members may be used for further supporting the liquid permeable material  26 . Furthermore, as discussed above with respect to  FIG. 1  and  FIG. 3 , in the case that the frame member  52  also acts as the collection electrode, the frame member  52  is also electrically grounded and formed from a conductive material. 
         [0039]    With respect to  FIG. 2 , the wet electrostatic precipitator  110  further includes a liquid collector  56  positioned proximate to the sieve outlets  54  for collecting the liquid being discharged from the sieve outlets  54 . According to the exemplary embodiment, the liquid collector  56  is in the form of a tray  56  that includes a bottom  58  and surrounding sidewalls  60  configured to guide the liquid to a liquid treatment system  62 . According to the exemplary embodiment, the liquid treatment system  62  includes a pump  64 , a filtration system  66 , and a heat exchanger  68 . Alternatively or in addition to the pump  64 , the filtration system  66 , and the heat exchanger  68 , the liquid treatment system  62  may include a blowdown system for reducing particulates within the liquid. The pump  64  is configured to direct the liquid from the liquid collector  56  to the filtration system  66 , which is configured to remove particulate emissions from the liquid. The pump  64  then continues to direct the liquid through the heat exchanger  68  for recovering thermal energy from the liquid. While the liquid may be removed from the wet electrostatic precipitator  110 , the liquid may also be redirected back into the liquid supply conduit  46  for reuse through the liquid permeable material  26 , as illustrated schematically in  FIG. 2 . It will be appreciated that the pump  64 , filtration system  66 , and heat exchanger  68  may be selected and assembled in order to accommodate any performance requirements for treating the exhaust of any given industrial process. For this reason, the pump  64 , filtration system  66 , and heat exchanger  68  may be selected and assembled per known requirements readily appreciated by those having ordinary skill in the art. 
         [0040]    According to the exemplary embodiment, the liquid is supplied to the wet electrostatic precipitator  110  during assembly thereof for an initial use. While a portion of the liquid may evaporate during use, particularly because the liquid permeable material  26  is exposed directly to the exhaust, the temperature differential between a relatively humid exhaust and the liquid permeable material  26  also generates a condensate to form on the liquid permeable material  26 . In turn, the liquid and the condensate will flow simultaneously into the tray  56  and the liquid treatment system  62  for reuse through the wet electrostatic precipitator  110 . In other words, any liquid losses may be offset by the addition of the condensate from the flue gas. Of course, in the event that too little or too much liquid flows through the wet electrostatic precipitator  110 , the plurality of sieves  24  are fluidly connected to a liquid supply (not shown) for additional liquid or a liquid drain (not shown) for removal, respectively. Alternatively, the plurality of sieves  24  may only be fluidly connected to the liquid supply (not shown) if reuse of the liquid and/or condensate is not desirable. Furthermore, in the event that the electrostatic precipitator  110  is configured to treat the exhaust in stages, then a variety of liquids, such as ammonia, amine, etc., may be supplied for each of the stages, in which the liquid collector  56  may have one or more additional compartments for collecting the variety of liquids, respectively. 
         [0041]      FIG. 5C  and  FIG. 5D  show additional embodiments of a sieve  124 ′,  124 ″. With respect to  FIG. 5C , the sieve  124 ′ includes the sleeve  37  of liquid permeable material  26  wrapped around a core  152 ′. The sleeve  37  of the liquid permeable material  26  generally surrounds at least a portion of the core  152 ′. Thereby, the sleeve  37  is attached to and supported by the core  152 ′ such that the sieve  37  maintains a predetermined shape regardless of being attached to one or more support members. According to an exemplary embodiment, the core  152 ′ is a foam material, but may be any generally rigid material for supporting the sleeve  37  thereon. 
         [0042]    One of the preferred embodiments of a sieve is to use the liquid permeable material in the form of elongated cordage such as twisted or braided rope.  FIG. 9  shows a set of ropes  314  stretched to be in tension between two support members  310  and  312 . This set of ropes is the sieve system. However the tension mechanism is not limited to springs  316  as shown in the figure; other mechanisms that keep the ropes in tension can be used. 
         [0043]      FIG. 10  shows the details of how the hollow top support delivers liquid from the water inlet  318  to the ropes  316  through a set of holes  320  in the top panel  322 . The holes act as a pressure adjuster. Bottom panel  324  acts as a spacer. For this embodiment,  FIG. 5D  shows the cross-section of the sieve  124 ″ which is the liquid permeable material  26  in the form of an elongated cordage  137 ″, such as a rope. The cordage can have circular cross section or other shapes, such as a rectangular tape or strip as shown in  FIG. 5E . It will be appreciated that the liquid permeable material may be formed into alternative structures configured to receive and encourage the flow of liquid therealong. 
         [0044]    In addition to the liquid permeable material  26  being formed according to various embodiments from a mat or a rope, as discussed above, the liquid permeable material  26  may also be woven as shown in  FIG. 6 . With respect to the woven material, also referred to herein as a braided sleeve  37 , the braided sleeve  37  may have greater strength than the mat material and further disrupt the liquid flowing therealong for increased surface area and, in turn, improved capture of particulate emissions. According to an exemplary embodiment, the braided sleeves  37  may be oriented at any desirable angle and even form a “net-like” plurality of sieves  37 . For example, two or more generally parallel rows of woven liquid permeable material  26  may extend together in tension between support members, such as by being attached to both the support member  44  and the bottom  58 , shown in  FIG. 2 . 
         [0045]      FIG. 7  and  FIG. 8  show a third exemplary embodiment of a wet electrostatic precipitator  210  (no discharge electrodes are shown) and an arrangement  238  of a plurality of sieves  224 . As discussed briefly above with respect to alternative embodiments, the plurality of sieves  224  is arranged to define a plurality of gaps  228  through which the exhaust flows from a duct inlet  220  to a duct outlet  222  with like numbers indicating like features discussed above. More particularly, the arrangement  238  of the plurality of sieves  224  includes four sieves  224 . According to the exemplary embodiment, the sieve arrangement  238  includes the sieves  224  offset and parallel from each other along a linear row. Notably, the plurality of sieves  224  are oriented generally horizontally and, as such, generally perpendicular to a flow direction of the exhaust. While the sieves  224  are distributed about a flow chamber  214  generally evenly to define like gaps  228 , it will be appreciated that more or less sieves  24  may be used with varying orientation and placements within the duct  12 . As defined herein, the terms “generally vertically” and “generally horizontally” may also include a horizontal component and vertical component, respectively. For example, as shown in  FIG. 6 , the exemplary embodiment of the arrangement  238  is generally horizontal but includes a vertical component to encourage flow via gravitation. Thereby, the arrangement  238  is configured for treating a generally vertical flowing exhaust (i.e., a vertical flow ESP). 
         [0046]    The sieve arrangement  238  includes a generally horizontally extending support member  244 , which defines a liquid supply conduit  246  extending therethrough. Furthermore, an elongate slot  248  extends longitudinally along a length of the support member  244 . The slot  248  extends through the support member  244 , into a liquid supply conduit  246 , and is configured to receive a liquid permeable material  226  of the sieve  224  and fasten therein. Thereby, the support member  244  supports the generally horizontal orientation of the liquid permeable material  226 , while the slot  248  further defines a sieve inlet  250  through which liquid is introduced into liquid permeable material  226 . According to the exemplary embodiment, the support member  244  and the liquid supply conduit  246  are in the collective form of a single elongate tube; however, it will be appreciated that another structure for supporting the sieves  224  and providing for the supply of liquid to the sieve inlet  250  may be so used. 
         [0047]    The liquid permeable material  226  for each of the sieves  224  of the arrangement  238  joins together as a single, unitary inlet end portion  250  of liquid permeable material  226 , which is fastened to the support member  244  within the slot  248 . The liquid permeable material  226  extends from the slot  248  and wraps around the support member  244 . In other words, the liquid permeable material  226  envelops the support member  244  in the form of a sleeve  237 . In turn, the liquid permeable material  226  extends along the support member  244  such that the support member  244  supports the liquid permeable material  226  against the exhaust flow. According to the exemplary embodiment, the sleeve  237  wraps tightly around the support member  244 , rather than hanging loosely from the support member  244 . The liquid permeable material  226  and the support member  244  extend toward a sieve outlet  254 . According to the exemplary embodiment, the sieve inlet  250  extends along a longitudinal length of the support member  244  and the sieve outlet  254  is at a longitudinal end portion of the liquid permeable material  226 . However, it will be appreciated that the sieve inlet and outlet  250 ,  254  may alternatively include or additionally include further structure, which may define, respectively, the inlet and outlet. 
         [0048]    The wet electrostatic precipitator  210  further includes a liquid collector  256  positioned proximate to the sieve outlets  254  for collecting the liquid being discharged from the sieve outlets  254 . According to the exemplary embodiment, the liquid collector  256  is in the form of a tray  256  that includes a bottom  258  and surrounding sidewalls  260  configured to guide the liquid to the liquid treatment system  62  as discussed above in greater detail. 
         [0049]    In use, the exemplary embodiments of the wet electrostatic precipitator  10  includes the plurality of sieves  24  for treating the exhaust as shown in  FIGS. 1-5A . As such, the exhaust passes through the duct  12  from the duct inlet  20  to the duct outlet  22  in the three stage process as shown in  FIG. 1 , but with additional reference being made to the sieves  24 , liquid collector  56 , and liquid treatment system  62  shown in  FIGS. 2-5A . However, it will be appreciated that this use applies similarly to the additional embodiments discussed above in greater detail, such as those shown in  FIGS. 5B, 6, and 7 . 
         [0050]    With respect to  FIGS. 1-5A , the liquid, such as water or alkali solution, is directed from the liquid supply via the pump  64  and into the liquid supply conduit  46 . Because the liquid permeable material  26  extends through slot  48  and into the liquid supply conduit  46 , the liquid absorbs into the liquid permeable material  26  and passes through the sieve inlet  50  along the remainder of the sieve  24 . More specifically, the liquid flows along the liquid permeable material  26  from the sieve inlet  50  toward the sieve outlet  54 . According to the exemplary embodiment, such liquid flow along each of the sieves  24  occurs generally simultaneously in each of the first, second, and third stages of treatment. However, it will be appreciated that each stage may be operated at different or like times and/or with different or like liquids depending on the treatment. 
         [0051]    While the liquid flows along the sieve  24 , the exhaust from the industrial process enters the flow chamber  14  through the duct inlet  20  and initially impacts the first portion  30  of the plurality of sieves  24  during the first stage of treatment. Specifically, the particulate emissions carried within the exhaust directly impact the liquid flowing along the liquid permeable material  26  and collect on the liquid permeable material  26  in order to remove the particulate emissions from the exhaust. In turn, the liquid continues to flow along the liquid permeable material  26  and guide the particulate emissions that accumulate thereon toward the sieve outlet  54 . The liquid flow continually cleanses the liquid permeable material  26  during use for additional accumulation and removal of particulate emissions. According to the exemplary embodiment, the first stage also acts as a scrubber and, as such, the liquid is particularly configured for treating the exhaust. For example, the liquid is an alkali solution that reacts with the contents of the exhaust for scrubbing the exhaust within the wet electrostatic precipitator  10 . During some exemplary treatments, the particulate emissions may be pre-charged by one or more discharge electrodes prior to entering the first stage. 
         [0052]    The exhaust flowing into and around the plurality of sieves  24  has an elevated temperature relative to the liquid flowing along the liquid permeable material  26 . For example, the temperature of the exhaust entering the duct inlet  20  may be greater than 130° F., such as between approximately 130° F. and approximately 350° F. As such, the first portion  30  of the plurality of sieves  24  may be formed from materials, such as those discussed above, configured to survive and operate within relatively high temperatures and corrosive gas. Furthermore, the first portion  30  may be configured to operate as a heat exchanger and/or scrubber for lowering the exhaust temperatures for subsequent stages. The temperature of the hot gases is lowered by heat transfer and condensation or evaporation; liquid will evaporate if the gases are hot and unsaturated; and condensation will occur when the gases become saturated due to cooling. According to an exemplary embodiment, the exhaust tends to reduce in temperature to an operating temperature of approximately 130° F. within the flow chamber  14  in the presence of the cooler liquid, which absorbs at least a portion of the excess thermal energy from the exhaust. According to the exemplary embodiment, the exhaust also includes an amount of liquid vapor, such as water vapor, that condenses on the liquid permeable material  26  in the form of condensate. The condensate and liquid flowing toward the sieve outlet  54  thereby collect accumulated particulate emissions and thermal energy for completing the first stage of treating the exhaust. By way of example, the condensation may be desirable for reducing a volume of flue gas to be treated in subsequent stages, conserving liquid by reuse, and a reduction in CO 2  emissions. 
         [0053]    During the second stage of treatment, the first stage is effectively repeated; however, the second stage further includes treatment via the plurality of discharge electrodes  36 . More specifically, the second portion  32  of the plurality of sieves  24  is electrically grounded, the plurality of discharge electrodes  36  is electrically connected to the current source for generating the high voltage electrical field therebetween. The high voltage electrical field generates charged particles that attach to particulate emissions within the exhaust. In turn, the charge particulate emissions become attracted to the electrically grounded sieves  24  for further removal of particulate emissions from the exhaust and accumulation on the liquid permeable material  26 . Condensation of water vapor is expected to occur in the  2   nd  and  3   rd  stages of treatment. 
         [0054]    The third stage of treatment effectively repeats the first stage of treatment via the third portion  34  of the plurality of sieves  24  positioned proximate to the duct inlet  20  and downstream of the first and second portions  30 ,  32 , respectively. As such, the third stage is configured to produce a final removal of the particulate and gaseous emissions and thermal energy before discharging the treated exhaust to the environment or other location in the industrial process. It will be appreciated that the first, second, and third stages may be practiced alone or in any combination with each other for treating exhaust. For example, the plurality of sieves  24  may be used solely for particulate collection by impaction or electrostatic precipitation, scrubbing, or for thermal energy recovery. 
         [0055]    With respect to the first, second, and third stages, the liquid, alone or in combination with the condensate, discharges from the sieve outlet  54  and into the tray  56 , which directs the liquid toward the liquid treatment system  62 . The pump  64  forces the liquid through the filtration system  66 , which removes the particulate emissions from the liquid, and into the heat exchanger  68 . The heat exchanger  68  then recovers thermal energy from the liquid for any variety of uses as will be appreciated by those of ordinary skill in the art to improve the efficiency of the industrial process. Once the liquid treatment system  62  removes and recovers the particulate emissions and the thermal energy from the liquid, the liquid is redirected back into the liquid supply conduit  46  for reuse. Alternatively, some or all of the liquid may be disposed of and additional liquid from the liquid supply may be directed into the liquid supply conduit  46  for continued treatment of the exhaust. 
         [0056]    To improve the charging of the particulates and improve their capture, some “partial sieve assemblies” may be added in series to provide a bypass path for the gases. This is shown in  FIG. 11 , where two sieve assemblies  324  and  326  extend across the entire flow path and two of the sieve assemblies  328  and  330  extend only partially across the flow path so some of the gases are forced to flow in a zig-zag pattern across the discharge electrodes as shown by arrows  18 . The path crosses a series of discharge electrodes  36 . The open section can be at the top or bottom of the ESP, or one of the two sides (as shown in  FIG. 11 ). This arrangement can improve particulate charging and capture. 
         [0057]    While the present invention has been illustrated by the description of one or more embodiments thereof, and while the embodiments have been described in considerable detail, they are not intended to restrict or in any way limit the scope of the appended claims to such detail. The various features shown and described herein may be used alone or in any combination. For example, sleeves of different cross-sections can be used in different parts of the ESP. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope of the general inventive concept.