Abstract:
Method and apparatus for treating air containing hydrogen sulfide gas, volatile organic compounds, heavy metals and other mercaptans in order to reduce odor and corrosion related to wet wells, dry pits, grease traps and the like. The system comprises a first and second stage air treatment system. A vacuum pump in the primary (stage  2 ) treatment housing vacuums the contaminated air from the source and pumps the air through a set of diffusers into a treatment fluid wherein the air is then passed through a pair of porous plates and upward through a discharge pump and then into the atmosphere. Prior to treating the air in the primary housing, it is treated in a pretreatment dry air filter wherein the air is inlet into the pretreatment (stage  1 ) housing and then through a microfilter prior to being passed into the primary housing for further treatment.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to air treatment and, more particularly, is concerned with multi-stage system for removing odor from sewage treatment related devices. 
     2. Description of the Prior Art 
     Air treatment devices have been described in the prior art, however, none of the prior art devices disclose the unique features of the present invention. In U.S. Pat. No. 6,616,733 dated Sep. 9, 2003, Pellegrin disclosed a method and means for filtering an air stream with aqueous froth. In U.S. Pat. No. 7,588,627 dated Sep. 15, 2009, Kijlstra, et al., disclosed a process for the removal of hydrogen sulfide and mercaptans from a gas stream. In U.S. Pat. No. 6,350,302 dated Feb. 26, 2002, Hallstead, Sr., disclosed an air filtration system. In U.S. Pat. No. 6,083,307 dated Jul. 4, 2000, Dular disclosed a water filter kit for drywall dust control. In U.S. Pat. No. 5,858,072 dated Jan. 12, 1999, Motoda disclosed a gas suction filtration apparatus. In U.S. Pat. No. 5,261,933 dated Nov. 16, 1993, Greene disclosed a vent gas deodorizing system. In U.S. Pat. No. 3,856,487 dated Dec. 24, 1974, Perez disclosed a gas scrubber. While these air treatment devices may be suitable for the purposes for which they were designed, they would not be as suitable for the purposes of the present invention as hereinafter described. 
     SUMMARY OF THE PRESENT INVENTION 
     The present invention discloses a method and apparatus for treating air containing hydrogen sulfide gas, volatile organic compounds, heavy metals and other mercaptans in order to reduce odor and corrosion related to wet wells, dry pits, grease traps and the like. The present invention comprises a first and second stage air treatment system. A vacuum pump in the primary (stage  2 ) treatment housing vacuums the contaminated air from the source and pumps the air through a set of diffusers into a treatment fluid wherein the air is then passed through a pair of porous plates and upward through a discharge pump and then into the atmosphere. Prior to treating the air in the primary housing, it is treated in a pretreatment dry air filter wherein the air is inlet into the pretreatment (stage  1 ) housing and then through a microfilter prior to being passed into the primary housing for further treatment. 
     An object of the present invention is to remove undesirable compounds from the air of wet wells, dry pits, grease traps and the like. A further object of the present invention is to reduce the odor of the air treatment stream. A further object of the present invention is to provide a non-toxic discharge comprising treated air. A further object of the present invention is to provide a means for air treatment which can be easily operated by a user. A further object of the present invention is to provide an air treatment system which can be relatively inexpensively manufactured. 
     The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention. In the accompanying drawings, like reference characters designate the same or similar parts throughout the several views. 
     The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is best defined by the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the invention may be more fully understood, it will now be described, by way of example, with reference to the accompanying drawings in which: 
         FIG. 1  is a cross sectional view of the present invention. 
         FIG. 2  is an environmental view of the present invention. 
         FIG. 3  is a perspective view of a portion of the present invention. 
         FIG. 4  is a perspective view with cut-away portions of the present invention. 
         FIG. 5  is a perspective view of a portion of the present invention. 
     
    
    
     LIST OF REFERENCE NUMERALS 
     With regard to reference numerals used, the following numbering is used throughout the drawings. 
     
       
         
               
               
             
           
               
                   
               
             
             
               
                 10 
                 present invention 
               
               
                 12 
                 stage 1 filter 
               
               
                 14 
                 stage 2 filter 
               
               
                 16 
                 enclosure 
               
               
                 18 
                 inlet nozzle 
               
               
                 19 
                 inlet 
               
               
                 20 
                 outlet 
               
               
                 22 
                 direction arrow 
               
               
                 24 
                 discharge pipe 
               
               
                 26 
                 slot 
               
               
                 28 
                 microfilter 
               
               
                 30 
                 microfilter 
               
               
                 32 
                 inlet 
               
               
                 34 
                 compartment 
               
               
                 36 
                 compartment 
               
               
                 38 
                 outlet 
               
               
                 40 
                 enclosure 
               
               
                 42 
                 lower compartment 
               
               
                 44 
                 treatment fluid 
               
               
                 46 
                 upper compartment 
               
               
                 48 
                 plate 
               
               
                 50 
                 plate 
               
               
                 52 
                 slots 
               
               
                 54 
                 vacuum motor 
               
               
                 56 
                 direction arrows 
               
               
                 58 
                 air diffuser 
               
               
                 60 
                 distribution pipe 
               
               
                 62 
                 diffuser slots 
               
               
                 64 
                 drain pipe 
               
               
                 66 
                 control valve 
               
               
                 68 
                 air vent 
               
               
                 70 
                 control valve 
               
               
                 72 
                 vacuum relief valve 
               
               
                 74 
                 inlet 
               
               
                 76 
                 outlet 
               
               
                 78 
                 arrows 
               
               
                 80 
                 ground 
               
               
                 82 
                 wet well 
               
               
                 84 
                 cover 
               
               
                 86 
                 septic fluid 
               
               
                 88 
                 froth 
               
               
                 90 
                 drop 
               
               
                 92 
                 deflector plate 
               
               
                 94 
                 plate 
               
               
                 96 
                 aperture 
               
               
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following discussion describes in detail at least one embodiment of the present invention. This discussion should not be construed, however, as limiting the present invention to the particular embodiments described herein since practitioners skilled in the art will recognize numerous other embodiments as well. For a definition of the complete scope of the invention the reader is directed to the appended claims.  FIGS. 1-5  illustrate the present invention wherein a method and apparatus for treating air is disclosed. 
     Turning to  FIGS. 1-5 , therein is shown the present invention being generally shown at  10  comprising a Stage  1  dry filtration system  12  and a Stage  2  wet filtration system  14 . The Stage  1  filtration system  12  comprises an enclosure or housing  16  having an air inlet nozzle  18  leading into an inlet conduit  19  and an outlet  20  wherein the inner air circulation pattern is shown at arrows  22  and having a first micro air filter  28  and a second micro air filter  30  internal housing  16  so that air passes through the microfilter  28 ,  30  and then out a vertically disposed central discharge pipe  24  comprising a centrally disposed slotted air conveyance pipe  24  having a plurality of entry slots  26  therein and then into the outlet conduit  20  of the enclosure  16  and into the inlet conduit  32  of the Stage  2  filtration system  14 . Arrows  78  illustrate the contaminated airstream containing odorous vapors entering inlet  18 . Note that the Stage  1  filter has a first upper compartment  34  containing the microfilter  28 ,  30  and a second lower compartment  36  containing the outlet  20  so that the two compartments are kept separate from each other in order to improve sanitary conditions. The Stage  2  filter system has an inlet  32  along with an outlet conduit  38  comprising an enclosure or housing  40  having a lower compartment  42  containing a treatment fluid  44  therein and an upper compartment  46  containing first plate  48  and second plate  50  each having a plurality of holes/slots  52  therein, wherein the slots are oriented toward the outer portion of the plates  48 ,  50  with the center portion being solid, wherein a vacuum blower motor  54  provides means for inducing air flow through the Stage  1  and  2  systems and then out an outlet pipe  38  wherein a plurality of arrows  56  show the air flow through the Stage  2  filter system. Also shown is a solid deflector plate  92  which routes airflow outwardly and then immediately above plate  92  is plate  94  having a plurality of slots  52  disposed toward its center portion and being solid toward its outer portion. The unique orientation and arrangement of slots and solid portions of plates  48 ,  50 ,  92  and  94  create a winding path for the airflow which assures complete mixing, volitization of fluid in the airstream, an effectively dry airstream at outlet  38 , and increases residence time of housing  40 . Other features of the Stage  2  system include a stacked plurality of inner diffusers  58  having a central air distribution pipe or conduit  60  wherein the air passes through the diffusers and out a plurality of slots  62  into the treatment fluid  44 , through the plates  50 , through the upper compartment  46 , through the motor driven vacuum pump  54  and then out the outlet pipe  38 . Also shown is a drain outlet  64  having a control valve  66  thereon along with an air vent  68  having a control valve  70  thereon and a vacuum relief valve  72  in order to prevent the housing  40  from collapsing in the event the inlet pipe  32  becomes clogged. The vacuum relief valve has an inlet  74  and an outlet  76 . 
     Regarding plate  92 , this is a solid plate designed to deflect the airflow and fluid outwardly and away from the center of the tank  40 . There are no holes or slots in this plate. When the air is released from fluid  44  it cause a bubbling action and plate  92  prevents it from hitting the next full plate  94  with the central air slots  52 . Plate  94  also has an aperture  96  in its center to accommodate pipe  60 . A purpose of plate  92  is to prevent excessive bubble build up in the lower portion of the tank  40 . 
       FIG. 2  also shows an exemplary under the ground  80  wet well  82  with cover  84  containing a septic fluid  86  which emits sewage odors or the like. An inlet nozzle  18  is attached to one end of a non-corrosive EDPM hose  19  and inserted into the contaminated air space  82  where it draws the toxic air outwardly as a part of the airstream. The other end of the hose leads into the Stage  1  filter. A micro diffuser  58  is located in the lower compartment  42  of the tank  40 . This micro diffuser  58  is submerged in a concentrated organic solution  44  used to neutralize and remove volatile organic compounds, hydrogen sulfide gas, all other mercaptans, and heavy metals upon contact. 
     Regarding the diffusers  58 , one diffuser will lay flat on the bottom of the tank  40  and will contain air discharge slot openings  62  of 0.006 inch (all measurements are in inches) and the 2nd one will contain air slots opening of 0.004 and the top diffuser will have air slot openings of 0.002. These diffusers are located about 1 inch apart. This will provide a Multi Stage Micro Diffuser  58  that is critical in breaking down and separating the various sewer gases. When these gases are exposed to a vacuum, (negative pressure) they are easily separated due to their various densities, making their molecular structure accessible for our chemical solution to penetrate and destroy the toxic sewer gases. There is a unique chemical reaction that takes place when you combine the specific gravity of the treatment fluid and the vacuum/negative pressure environment that is created in the gas extractor. Plates  48 ,  50  are located 4 inches apart and each plate will contain air slot openings  52  of 0.002-0.004. This will allow a retention time of 0.75 seconds required before the treated gases are released either back into the atmosphere or the lift station where they were extracted from originally. Air slot openings  26  (0.003) to the Stage I dry air separator  12  is where the toxic gas separation actually starts. This will provide one long micro  24  diffuser inside the canister  16 . Plate  94  and its slots  52  are similar to plates  48 ,  50 . 
     Also shown is a 2 hp regenerative blower  54  and a vacuum relief valve  72 . The vacuum relief valve  72  is a critical component to keep the tank  40  from imploding in the event the air intake/stage  1  dry air filter  12  becomes clogged up. 
     The treatment fluid  44  is an aqueous solution comprising a clear, colorless organic liquid having a ph of about 10 and a boiling point ranging from 212-370 degrees Fahrenheit. 
     The present invention  10  is a fully self-contained, non-corrosive, multi-chambered, energy efficient, non-hazardous, organic and all green device created to extract, process instantly upon contact, toxic gases such as hydrogen sulfide, volatile organic compounds (VOC&#39;s), heavy metals and all other mercaptans which occur naturally in wet wells  82 , dry pits, grease traps and the like. The toxic gases are pulled from the wet well  82 , dry pit, or grease trap through specifically designed non-corrosive micro diffusers (Stage  1  and  2  at  12 ,  14 ) which help break down the toxic gases. 
     Immediately above the concentrated solution of treatment fluid  44  are multi layers of slotted plates  48 ,  52 ,  94  designed to help remove VOC&#39;s and hydrogen sulfide gas. The contaminated air is pulled from the well by placing a vacuum on the tank  40 . As the vacuum is created, contaminated air is pulled from the air space of the wet well/dry pit or grease trap  82  through the two micro diffusers (Stage  1  and  2  at  12 ,  14 ) and through the concentrated solution of treatment fluid  44  where up to 80% of all the VOC&#39;s and hydrogen sulfide gas, other mercaptans and heavy metals are instantly removed. As the toxic air travels through the micro diffuser  58  submerged in the concentrated solution  44  agitation occurs. This agitation causes micro foaming froth  88  to accumulate on the plates  48 ,  50 ,  94  of the tank and to drop or drip  90  therefrom. As the vacuum occurs in the tank, this pulls the highly concentrated supercharged foam and froth up onto the plates  48 ,  50 . As the plates  48 ,  50  become saturated and coated with the supercharged micro-fine bubbles created by the agitation in the bottom  42  of the tank, the remaining VOC&#39;s, hydrogen sulfide gas, mercaptans and heavy metals are substantially neutralized and removed as they pass through the saturation chambers. This process is fast and irreversible in the state of the process. Final discharge is substantially clean, organically processed air. 
     This process of extracting and removing toxic gases instantly and on contact is accomplished by using a unique combination of supercharged, micro-foaming, micro diffusers, fluid pressure in a confined space and a regulated vacuum pressure, simultaneously in a multi chambered air tight tank. This makes the present invention a cost-effective closed loop or open loop odor control and toxic gas removal process for wet wells, dry pits and grease traps. 
     The present invention reduces hydrogen sulfide gas by up to 95%, reduces odor by up to 95%, is an all organic solution, non-hazardous discharge, reduces B.O.D. and C.O.D., retention time &gt;2 seconds (instantaneous and irreversible), water soluble solution, non-toxic discharge, all green construction, fully self contained, no moving parts, 99% maintenance free, super energy efficient, installs in 5 minutes, no retro fitting required, no wiring required (plug into 120 volt outlet), concentrated solution—non DOT regulated, concentrated solution—ships UPS, concentrated solution lasts 90 to 120 days, and the disposal method is to empty used solution into wet well/dry pit or grease trap.