Abstract:
An aerobic treatment system for wastewater is disclosed herein. The aerobic treatment system is comprised of a basin, which receives wastewater through an inlet pipe, the inlet pipe depositing the untreated wastewater to the lower portion of the basin. The wastewater must then flow from the lower portion of the interior of the basin through a fibrous filter and through an outlet filter to the outlet section of the aerobic treatment system. While resident within the lower portion of the basin, the wastewater is treated through aeration by an insertion of air through an air inlet pipe and diffusing the air within the untreated wastewater below the fibrous filter. The entire aerobic treatment system of the present invention is designed such that the filtering mechanisms may be readily removed or cleaned on a routine basis by the user. Further, the aerobic treatment system described herein adequately treats and lowers the bacterial count through aeration of the wastewater while the wastewater is resonant within the basin.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates in general to wastewater treatment systems and more particularly to an aerobic polishing treatment unit for wastewater. More particularly, the present invention relates to a redundant aerobic treatment system utilized to treat outflow wastewater from a primary treatment system or septic treatment system. 
     2. Discussion of the Prior Art 
     A large number of systems for treatment of contaminants in water, such as effluent from wastewater treatment facilities, are variously known in the prior art. Many of the various prior art type wastewater treatment facilities may utilize AeroDiffuser systems, septic tank or other designs, which are meant to reduce various bacterial, or contaminant counts within the effluent. A number of these prior art systems are considered to be advance treatment systems, which provide an initial treatment of effluent directly from the source. A number of these advance treatment systems or main treatment systems provide either initial or standard treatment within the septic system by taking the wastewater and lowering the appropriate bacterial count to an acceptable level. 
     However, some of these designs require additional or background treatment facilities due to the poor soil conditions, system capacities, bulk of material or other environmental circumstances in order to adequately treat the wastewater. This may be particularly the case when the resident time of the effluent within the standard septic treatment system is insufficient. Such background, post-treatment or ‘polishing’ facilities are used to catch overflow or to ‘polish’ treat the outflow from the main wastewater treatment facility. Polishing systems have typically been comprised of sand filters and are utilized for reduction of bacterial count or suspended solids from the effluent. These polishing filters are utilized to remove particulate and other material not caught by the primary filtering system. 
     SUMMARY OF THE INVENTION 
     The present invention therefore seeks to solve the above-mentioned problems and shortcomings of the prior art. In general, the present invention relates to a background aerobic polishing treatment system for wastewater fluid wherein the aerobic treatment unit treats the wastewater after primary treatment, such background treatment occurring within a basin through an aeration process. The polishing system for wastewater of the present invention then passes the treated wastewater to the outlet lines of the septic system. 
     The aerobic treatment system of the present invention may also be utilized in order to solve overflow problems from a main septic treatment system or to provide air infusion as a treatment to wastewater fluid. An additional use may reside in the ability of the polishing system of the present invention to rejuvenate a lateral field where the outflow of a septic tank has clogged or prevented further use thereof. 
     One object therefore of the present invention is to provide an aerobic polishing system for wastewater fluid wherein the unit of the present invention may be placed subsequent to a main wastewater treatment facility in order to treat the outflow from the wastewater treatment facility and ensure proper final treatment thereof. 
     An additional object of the present invention is to provide an aeration polishing treatment system for wastewater fluid wherein the wastewater is treated in order to adequately lower the bacterial count of the wastewater. 
     An even further object of the present invention is to provide an aerobic treatment system for wastewater wherein proper treatment of the wastewater may be completed when the entire wastewater treatment facility is located on either poor soil or in a small or confined area. 
     Another object of the present invention is to provide an aerobic polishing treatment system for wastewater wherein the aerobic treatment unit of the present invention utilizes a basin, which receives the wastewater, the wastewater treated by air injection and passed through an outlet filter and through a fibrous filter to the wastewater treatment outlet line. 
     An additional object of the present invention is to provide an aerobic polishing treatment system for wastewater wherein the aerobic treatment unit of the present invention may be utilized in series as a primary treatment facility if needed. 
     Moreover, an additional object of the present invention is to ensure lower bacterial count of the wastewater fluid by use of the aerobic polishing treatment system for wastewater shown herein and which may provide three additional stages of filtering and treatment. The wastewater treatment unit utilizes a compressor to inject air into the aerated wastewater contained within a basin. The aerated wastewater must first flow through a fibrous filter in order to reach the outlet filter. The outlet filter is interposed between the fibrous filter and the outlet line so that the aerated wastewater is filtered prior to flowing through the outlet lines. 
     The aerobic polishing treatment system for the present invention ensures that the bacterial count for the wastewater coming from a primary wastewater treatment facility may be additionally reduced in order to meet proper environmental criteria. 
     Arrangements within the scope of the present invention provide further advantages in that the aerobic treatment system for the present invention, which retains the aerated wastewater, may be located in different positions within a primary wastewater treatment facility or may be placed in series as a primary treatment facility. 
     Examples of arrangements within the scope of the present invention are illustrated in the accompanying drawings and described hereinafter but it will be understood that neither the drawings nor the descriptions hereof are presented by way of limitation in that other arrangements also within the scope of the present invention will appear to those skilled in the art upon reading the disclosure set forth herein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross-sectional view of the aerobic treatment system for wastewater fluid of the present invention; 
     FIG. 2 is a close-up cross sectional view of the outlet filter for the aerobic treatment system shown in FIG.  1 . 
     FIG. 3 is a top sectional view of the aerobic treatment system depicted in FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The aerobic polishing treatment system for wastewater  10  of the present invention is shown in FIG. 1 in cross section. In the design shown in FIG. 1, the system is mostly retained within a basin  20  which may be a large cylindrical barrel type basin to retain the aerated wastewater  24  located in the bottom portion of basin  20 . The basin  20  has several inlets which allow both wastewater and air to flow into the interior of the sealed basin. Additionally, the basin  20  has a removable lid  17  which may be snapped or threadably retained on the top portion thereof for access to the interior of the aerobic polishing treatment system  10  of the present invention. The basin  20  as depicted in FIG. 1 may be of a barrel type design and may be made of a plastic or other leak proof material such that the aerated wastewater contained within the lower portion of the basin  20  is retained therein without spillage or leakage. As shown in FIG. 1, the basin may be, for example, a container which has a volume of approximately 75 or 80 U.S. gallons, only a portion of which contains the aerated wastewater  24  in the lower portion thereof. The aerated wastewater  24 , as depicted in FIG. 1, may fill only a portion of the basin  20  such as, for example, approximately 30 gallons or slightly more for treatment by the aerobic polishing treatment system of the present invention. 
     The basin  20  has an inlet pipe  14 , which has an open inlet area  12 . Inlet pipe  14  enters into the interior of the basin  20  and allows the wastewater to flow there through. Inlet pipe  14 , including the inlet portion  12  thereof, allows the wastewater to enter into vertical pipe portion  15  and exit through the inlet pipe outlet section  16  found at the lower area of the interior basin  20 . Inlet pipe  14  may be made of a PVC material or other similar plastic in order to adequately carry the wastewater to the lower interior of basin  20 . The inlet section or area  12  of inlet pipe  14  may be connected to the outlet of septic system or other type of advance treatment system and will receive the mostly or partially treated wastewater for further treatment. Thus, the aerobic polishing treatment system  10  of the present invention may be placed in series with other wastewater treatment systems in order to further aerate and treat the wastewater fluid flow thereby fully reducing bacterial and suspended particulate material therein. 
     As can be seen in FIG. 1, the wastewater flows into the interior of the basin  20  through the inlet section  12  of inlet pipe  14  and is deposited in the lower section of the basin  20  through the outlet portion  16  of the inlet pipe. The vertical section  15  of the inlet pipe allows the wastewater to by-pass the fibrous filter  22  located in the interior of the basin  20 . Shown in conjunction with FIG. 1, FIG. 3 depicts a top view of the construction wherein the vertical pipe portion  15  allows the wastewater to descend to the bottom portion of the basin wherein the fibrous filter  22  separates the treated and untreated sections of the wastewater  24 . 
     In addition to the vertical pipe portion  15  of inlet pipe  14 , air supply tube  35  is provided in order to provide airflow to the interior of basin  20  into the aerated wastewater  24 . The air supply tube  35  is connected at the air inlet  30  to a compressor or other device, which injects air into the interior of the basin and through air diffuser holes  32  found in the bottom section of air supply tube  35 . As previously indicated, the lower portion of basin  20  contains the aerated wastewater  24  and the air supply tube  35  provides a continuous flow of air for aeration treatment of the wastewater contained therein. Further, a quick disconnect valve  31  is provided between the air inlet and the air diffuser  32  in order to disconnect the compressor or air supply vehicle from the air supply tube  35 . This disconnect valve may be useful when entry into the interior of the basin  20  is required for servicing or cleaning. Thus, the compressor may be disconnected and thereby prevented from supplying additional air into the interior of the basin  20  by disconnecting the air supply tube at the disconnect valve  31 . Also found at the lower end of air supply tube  35  is cap  33  in order to close off the air supply tube and force the supplied air through air diffuser apertures  32 . 
     As shown in FIG. 1, the air supply tube  35  is provided so that fresh air is injected into the wastewater  24  in order for proper aeration treatment of the wastewater to be conducted. By continual application of air through the air diffuser  32 , bacterial and other elements may be removed and the content lowered within the wastewater  24  through known aeration techniques. Further, air which is injected into the basin  20  through the air supply tube  35  is vented the standard plumbing vent pipes of the septic system or through the outlet  40 . 
     As depicted in FIG. 1, separating the lower portion of the aerated wastewater  24  and the upper treated portion is fibrous filter  22 . Fibrous filter  22  is an extremely fine filtration mat for separation of solids and other material from the lower portion to the upper portion, the upper area of the aerated wastewater flowing to the outlet  40  of the basin  20 . Fibrous filter  22  may be made of a carbon, polyester or other plastic fine mesh material and may be replaced or cleaned on a regular basis during operation of the aerobic treatment system  10  of the present invention. Fibrous filter  22  allows the solids to remain in the lower section of the basin  20  and prevent the solids from flowing through the outlet filter  42  and outlet pipe  40 . The fibrous filter  22  is designed such that it prevents solid particulate material to flow from the lower portion of the basin  20  and will also act to properly filter wastewater within the polishing system of the present invention. Further, the outlet mesh filter  22  may be comprised of a carbon material, which adds to the denitrification of the effluent. The filter utilized may be a carbon impregnated fiber filter such as that manufactured by BON-AIRE Filters, Inc. of Marietta, N.C. The de-nitrification aspect resulting from the inclusion of the carbon based filter in the polishing system of the present invention avoids the requirement of having additional de-nitrification systems commonly found in wastewater treatment systems. Thus, the polishing filter of the present invention provides a three-stage filtration capability; oxygenation, fibrous filter  22  and lo outlet filter  42  in addition to the de-nitrification abilities of a carbon based filter element  22 . 
     As depicted in FIG. 1, the wastewater level has a water level  11  depicted so that water flows through the inlet and through the vertical pipe portion  15 . The water level  11  is such that water flows to the outlet  40 , which is placed slightly lower than the inlet section  12 . Thus, the water flow typical for use of the aerobic polishing treatment system of the present invention is such that wastewater flows through the inlet  12 , down vertical pipe portion  15  by-passing the fibrous filter  22 , through the outlet  16  of inlet pipe  14 , upward through the fibrous filter  22  and through the inlet  44  of outlet filter  42 . The water flow will then pass through the outlet filter  42  into the outlet  40  which passes the water through to either further treatment or to standardized lateral fields for dispersion of treated wastewater. 
     The outlet filter  42  of the present invention is depicted in FIG.  1  and in FIG. 2 wherein an inlet section  44  allows the treated wastewater to flow upward and through the outlet section  40 . Outlet filter  42  further treats the aerated wastewater to remove particulate material, which has bypassed the fibrous filter  22 . Outlet filter  42  of the present invention, as is depicted in FIGS. 1 and 2, has an outer wall  45  surrounding it allowing effluent fluid flow to enter upward through the inlet  44  and through the plurality of small openings  47  formed on the inner wall. The openings form weir or small dam type openings and effectively remove solid material from the effluent flow. As the fluid passes through the inner wall and openings  47  to the outlet  40 , the filtered and treated water exits the polishing filter system of the present invention. 
     The outlet filter  42  of the present invention which is placed in the interior of the basin  20  is designed so that it may be removed from the interior of the basin after removal of lid  17 . The outlet filter may then be cleaned in order to further remove particular material or other deposits which are formed or may accumulate therein. 
     The basin  20  of the aerobic treatment system of the present invention has a removable lid  17  for entry of the interior thereof. The removable lid may be threaded on or snap fitted or clamped on to the top portion of the basin. The lid  17  may be separated from top rim of the basin  20  by a gasket  13  in order to provide a water tight seal between the basin  20  and lid  17 . Thus, the gasket  13  which may be neoprene or other similar malleable material provides a water tight seal and prevents the leakage of wastewater from the interior of the basin. 
     As can be seen in FIG. 1, the water flow into the interior of the basin  20  follows a path through inlet  12 . The actual water level and also the resident time of the aerated wastewater  24  within the basin  20  depends on the use and volume of wastewater flowing through inlet  12  and also potentially on other environmental or waste characteristics. Thus, during high use, the fluid may remain in the container for only a short period of time. However under normal use circumstances, the wastewater will be aerated for a predetermined and limited time in order to properly remove bacteria and other elements through aerobic treatment of the wastewater. Further, the aerobic polishing treatment system  10  of the present invention may be provided in series with a multiple number of the units  10  connected together so that continual treatment of the wastewater in a plurality of basins is conducted. Further, the air supplied through air inlet  30  is provided by a compressor or other mechanism to inject air through the air supply tube  35 . The compressor supplies air continually to the interior of the basin  20 . The compressor, which is not shown, may be used to supply a large number of units  10  or may be utilized in a primary aeration treatment unit. Thus, for adequate air and fusion treatment of the wastewater, effluent flows into the interior of a single or a plurality of air treatment systems  10  of the present invention. 
     The aerobic treatment system  10  of the present invention may also be utilized as an overflow catch from a main wastewater treatment or septic system in order to ensure that, should there be an overflow of untreated wastewater, air infusion treatment of the wastewater will be implemented in order to reduce the bacteria and solid level of the fluid. Thus, as a secondary or redundant unit, the aerobic treatment system  10  of the present invention may be utilized to either lower bacterial count to an adequate level or prevent untreated overflow effluent to be dispensed to lateral lines or other septic fields. 
     While examples within the scope of the present invention are shown and discussed with reference to wastewater treatment it will be understood that devices within the scope of the present invention can be equally effectively used in other applications such as for example treatment of drainage water or other wastewater treatment systems in different form or format. 
     It is also understood that the forgoing examples are not by way of limitation of the present invention in that other arrangements within the scope of the present invention will occur to those skilled in the art upon reading the disclosure set forth herein.