ENHANCED BIOLOGICAL TREATMENT OF WASTEWATER

Abstract

The present invention relates to a new and novel process that combines several water treatment processes to biologically treat wastewater. The first treatment process is bioaugmentation using a select mixture of microorganisms grown from wastes collected from a Waste Water Treatment Plant (WWTP) to treat wastewater as it flows through its conveyance system. The second treatment process is employment of a flow control device that increases the holding capacity of the conveyance system to increase time for biological treatment and allow the contained water to be discharged at a controlled reduced and leveled rate. The third treatment process is a high-rate clarification system preferably using flocculating polymers to remove fine suspended solids from the wastewater that can be further treated in a series of containment structures positioned in a stream or riverbed to increase the treatment residence time.

Claims

1. A method for treating a stream of polluted wastewater by: growing select microorganisms at a Waste Water Treatment Plant (WWTP) using properly treated solid and liquid wastes generated or received at the WWTP along with other wastes; introducing a mixture of the select microorganisms into an inlet end of a wastewater conveyance system to convert said conveyance system into a treatment system able to inline destroy detrimental microorganisms, treat toxic organics, reduce BOD, and to remove nutrients from the stream of wastewater; providing an adjustable flow control device in said wastewater conveyance system to allow control of the accumulation of wastewater within the conveyance system, so as to control the residence time of the stream of wastewater in the conveyance system; and providing a high-rate clarification treatment that processes wastewater that has been biologically treated in the conveyance system to meet discharge limits and final use requirements.

2. The method of claim 1, wherein the mixture of select microorganisms contains free floating and film forming bacteria and phages that have an adverse effect on detrimental bacteria such as SBR bacteria and other microorganisms.

3. The method of claim 1, wherein the mixture of select microorganisms includes Bacillus Thuringiensis lsraelensis and Bacillus Sphaericus that are used to kill mosquito larvae.

4. The method of claim 1, wherein the preferred select mixture of microorganisms contains bacillus bacteria selected from the group including B. Subtiles, B. Licheniformes, B. Indicus, B. Coagulans, B. Cereus, and B. Clausii.

5. The method of claim 1, wherein the mixture of select microorganisms is grown at or near the site of entering pollution into the conveyance system using nutrients found in the pollution or other organic wastes as a food source.

6. The method of claim 1, wherein attached biocarrier surfaces are added to the conveyance system, which includes pipelines, canals, river, and streambeds, to promote the growth of select microorganisms as biofilms.

7. The method of claim 1, wherein the conveyance system may be a pipeline, canal, or a natural watercourse that is extended by a man-made canal or other conveyance system added alongside or within a river or stream to increase the residence time so biological treatment can continue to treat wastewater before entering the river or stream.

8. The method of claim 1, wherein biosolids or other wastes received from a WWTP are disinfected and lysed to produce a suitable food to grow the select microorganisms.

9. The method of claim 8, wherein the waste products to grow the select microorganisms are disinfected and lysed by methods including but not limited to mechanical, thermal, electrical, sonic methods, but preferably hydrodynamic cavitation, to kill unwanted competing microorganisms, including pathogenic bacteria and sulfur reducing bacteria (SRB) and to increase the food value of the waste products by releasing the cell protoplasm contents beneficial for growing the select microorganisms.

10. The method of claim 1, wherein the flow control device comprises an adjustable weir so as to create either a smaller reservoir of wastewater during dry weather conditions or a larger reservoir of wastewater during wet weather conditions, allowing control of the residence time of the wastewater in the reservoir to provide optimum time for the select microorganisms to treat the wastewater to appropriate levels.

11. The method of claim 10, wherein the flow control device controls and levels out the flow of wastewater from the conveyance system so that the flow does not exceed the capacity of any downstream treatment system.

12. The method of claim 10, wherein the flow control device is a V notch weir that can be mechanically adjusted to control the rate of flow of wastewater discharged from the conveyance system.

13. The method of claim 1, comprising the further step of screening floatables and disinfection after said high rate clarification step.

14. The method of claim 1, wherein the high-rate clarification system removes fine suspended solids including bacteria and other microorganisms by the use of a flocculating polymer and/or coagulant followed by disinfection when needed.

15. The method of claim 14, wherein the high-rate clarification system has a surface overflow rate greater than 10 gallons per minute per square foot and employs techniques selected from a group of technologies including dissolved air flotation, lamella gravity clarification, densified sludge, and ballast clarification using either sand or preferably magnetite.

16. The method of claim 14, wherein solids removed by the high-rate clarifier and any first flush wastewater are diverted into one or more containment structures that are either positioned in a riverbed that increases the biological treatment time or pumped to a nearby WWTP for further biological or dewatering treatment.

17. The method of claim 13, wherein when necessary, disinfection methods will be employed including treatment with chlorine, peracetic acid, UV, or ozone to kill pathogenic microorganisms in biologically treated wastewater before direct discharge into the environment.

18. The method of claim 14, wherein select microorganisms that have been removed by the high-rate clarifier are routed to a WWTP to provide a constant source of the select microorganisms to enhance the performance of the WWTP and to treat the wastewater in the conveyance system downstream of the WWTP when needed.

19. The method of claim 1, further comprising the steps of using the select beneficial microorganisms grown from municipal wastewater; for enhancing the performance of a WWTP; improving digesting of WWTP biosolids; treating CSO/SSO/Storm Water inline; treating toxic organics contained in wastewater from a wet weather event; and killing mold.

20. The method of claim 1, wherein the select microorganisms grown at the WWTP are pumped through a new pipeline positioned inside the conveyance system to the front end of the conveyance system to increase the residence time for biological treatment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Other objects, features and advantages will occur to those skilled in the art from the following description of a preferred embodiment and the accompanying drawings, in which:

[0062] FIG. 1 shows an overview of the treatment technologies employed according to the invention and how they are integrated to produce the desired result of economically treating wastewater.

[0063] FIG. 2, comprising FIGS. 2(a) and 2(b), shows a flow control device that can be adjusted to change the pool level in the conveyance system, which will vary the holding capacity of the conveyance system.

[0064] FIG. 3 shows a system for growing a mixture of preferred microorganisms at a WWTP to bioaugment the inline treatment of wastewater.

[0065] FIG. 4 shows the extension of a wastewater conveyance system and its placement inside a riverbed.

[0066] FIG. 5 shows a delivery system that takes select microorganisms grown at a WWTP and transports the select microorganisms either through a pipeline placed within the wastewater conveyance system or for other environmental purposes.

DETAILED DESCRIPTION OF THE INVENTION

[0067] While this invention is susceptible to embodiment in many different forms, there is shown in the drawings and will herein be described in detail specific embodiments, with the understanding that the present disclosure of such embodiments is to be considered as an example of the principles of the invention, and are not intended to limit the invention to the specific embodiments shown and described. In the description below, like reference numerals are used to describe the same, similar or corresponding parts in the several views of the drawings. This detailed description defines the meaning of the terms used herein and specifically describes embodiments in order for those skilled in the art to practice the invention.

[0068] FIG. 1 shows wastewater (1) flowing through a water conveyance system (2), such as a lake, river, impoundment structure or the like, into which is injected a mixture of select microorganisms (37) that treat the wastewater inside the water conveyance system (2) to consume undesirable organics. As indicated above, these microorganisms may include facultative bacilli and phages. The water conveyance system (2) that contains the flowing stream of wastewater (1) contains a plethora of biocarriers (14) that are attached to the inside surface of the conveyance system (2) to increase the amount of surface area for the growth of biofilm. Also injected at or near the beginning of the conveyance system (2) is a mixture of select microorganisms (37) that are grown in a growth system (38) shown in more detail in FIG. 3 that uses organic wastes (30) from a WWTP (36) and other organic wastes (31). A flow control device (4), shown in more detail in FIG. 2 is located at the end of the conveyance system (2) to control the flow rate and the level of wastewater in the water conveyance system (2) to give the microorganisms time to work. Biologically treated wastewater then flows through a screen device (5) that removes large solids and floatables. The screened wastewater then flows into a high-rate clarification device (6), which may take one of several forms as mentioned above, but preferably where polymer (11) is added to flocculate fine suspended solids for removal. Flocculants may be employed together with magnetite to remove the flocculated solids, e.g., as described in applicant's co-pending application Ser. No. 14/612,635, filed Feb. 3, 2015, and incorporated herein by this reference. The clarified wastewater then flows through a disinfection device (10) and then into the end conveyance, e.g., a river (12). Solids removed by the high-rate clarification device flow (7) into one or more solids settling containments (8). Supernatant from the solids settling containment (8) flows (9) into the river (12) or is land applied. Solids dredged from the solids settling containment (8) from time to time are either land applied or land filled (13).

[0069] FIG. 2, comprising FIGS. 2 (a) and (b), shows a flow control device (4) that can be adjusted to change the pool level in the conveyance system. The main purpose of the flow control device is to back up wastewater into the conveyance system to allow for additional time for biological treatment and to control and level out the flow of wastewater for subsequent treatment. The preferred flow control device is a V notch weir composed of two parts. One part (20) is a stationary weir and the other part is a movable weir (21) sealed to the stationary weir to prevent most leakage. The flow control device has basically two positions. One position (FIG. 2(a)) determines a low-level pool height (22) that is employed during dry weather and another position (FIG. 2(b)) determines a high-level pool height (23) that is employed during wet weather events. This allows the residence time of water in the conveyance system to be controlled to be substantially constant despite varying flow rates in dry and stormy weather. A mechanical device (24) powers the movable weir (21).

[0070] FIG. 3 shows a system for growing a mixture of select microorganisms comprised primarily of bacteria and phages to bioaugment the inline treatment of wastewater. Organic waste (30), specifically from a WWTP and other organic wastes (31) are macerated in a device (32) designed to blend and size reduce solids contained in the organic wastes (30 and 31). This blended product flows into a disinfector (33) that disinfects the organic wastes so that microorganisms contained in the organic wastes do not compete with the growth of the select mixture of microorganisms used in the treatment of wastewater. The preferred method to disinfect the organic wastes is by hydrodynamic cavitation, which also lyses cells contained in the organic wastes to improve the food value for the growth of the select microorganisms. The organic wastes that have been treated with hydrodynamic cavitation then flow into a recirculation tank (34) and are pumped (35) back to the disinfector to allow the organic wastes to be disinfected and lysed multiple times. Once suitably treated, the organic wastes flow to a grow tank (36) to feed the select mixture of microorganisms, preferably facultative bacillus bacteria and phages as discussed above. These microorganisms then flow (37) into the wastewater conveyance system (2) shown in FIG. 1.

[0071] FIG. 4 shows wastewater (40) flowing through a conveyance system (41) and into a conveyance system extension (42) that has been positioned within a riverbed and where biological treatment is taking place. The biologically treated wastewater within the conveyance system extension (42) is then screened (43) to remove floatables, then clarified (44) to remove suspended solids, and then disinfected (45) to kill pathogens before the treated water is discharged (46) into a riverbed (47). First the water is biologically treated in the conveyance system and then it is screened, then clarified, then disinfected before it is discharged into the river water.

[0072] FIG. 5 shows a biological grow system (52) that receives organic wastes (51) from a WWTP to produce select microorganisms that are either returned (53) to the WWTP (50) for use and piped (54) to the front end of the wastewater conveyance system (55) for inline bioaugmentation or used (56) for other environmental purposes.

[0073] While a preferred embodiment of the invention has been disclosed, the invention is not to be limited thereto, but only by the following claims.