System and method for wastewater treatment control through microorganism metabolic pathway optimization

Abstract

Increased control and efficiency over the wastewater purification can be achieved by allowing to selectively prioritize catabolic over anabolic processes via prioritization of the digestive function of microorganism in the activated sludge. The gas-dispersion return sludge is created using pure oxygen or oxygen containing trace amounts of ozone, which is blended with return sludge to create a mixture of gas and liquid, which is passed through an atomizer or a pump to instantly render the reactive gas to an ultra-fine bubble state. At least a portion of the ultra-fine bubbles dissolve within the sludge, raising oxygen to a critical level within a short time, activating the dormant microorganisms. The microorganism accumulate enough cATP upon initial encounter with the pollutants to prioritize their digestive function, and when exposed to pollutants present in wastewater, digest the pollutants using biochemical pathways different from the ones used in nature.

Claims

1. A method for wastewater treatment control through microorganism metabolic pathway optimization, comprising: providing sludge comprising microorganisms capable of digesting one or more pollutants by exercising a digestive function via one or more catabolic pathways to obtain energy and store the energy in a form of adenosinetriphosphate (ATP), wherein the sludge is substantially mostly free of the one or more of the pollutants; receiving by a computer a user input comprising at least one of a time of the digestion of the one or more of the pollutants and a degree of digestion of the one or more of the pollutants; storing by the computer an association between how quickly an at least reactive gas dissolves within the sludge to a predetermined concentration and a degree to which the microorganisms exercise the digestive function upon encountering the one or more of the pollutants following the at least one reactive gas dissolution; determining by the computer a time within which the at least one reactive gas needs to dissolve to the predetermined concentration within the sludge based on the user input using the association; generating by a gas generator controlled by the computer the at least one reactive gas that is provided into the sludge; forming a gas-dispersion return sludge by at least partially dissolving, by one of an atomizer or a pump under a control of the computer, the at least one reactive gas in the sludge during the determined time to reach the predetermined concentration within the sludge; forming a mixed liquor by combining under a control of the computer the gas-dispersion return sludge with a wastewater that comprises the one or more of the pollutants, wherein upon encountering the one or more of the pollutants in the wastewater, the microorganisms store an amount of the ATP during an initial time period that is dependent on the determined time and wherein the microorganisms exercise the digestive function during a further time period based on the amount of the ATP created and stored during the initial time period.

2. A method according to claim 1, wherein the predetermined concentration is comprised within a range of predetermined concentrations, further comprising selecting by computer the predetermined concentration from the predetermined concentration range based on the user input.

3. A method according to claim 1, wherein one of the pump and the atomizer pressurize the at least one reactive gas during the formation of the gas-dispersion return sludge.

4. A method according to claim 1, wherein the microorganisms prioritize the digestive function when the time to reach the predetermined concentration of the at least one reactive gas in the sludge is not more than 4 seconds.

5. A method according to claim 1, wherein the at least one reactive gas comprises oxygen and the predetermined concentration of the oxygen is at least 10 mg/l.

6. A method according to claim 5, wherein the at least one reactive gas further comprises trace amounts of ozone.

7. A method according to claim 1, wherein the wastewater is from a dairy farm and the gas generator and at least one of the pump and the atomizer are located on the dairy farm.

8. A method according to claim 1, wherein the wastewater is from a ship and the gas generator and at least one of the pump and the atomizer are located on the ship.

9. A method according to claim 1, further comprising: controlling a speed with which the at least one reactive gas is provided into one of the pump and the atomizer via a gas velocity volume control valve at an inlet of one of the pump and the atomizer.

10. A method according to claim 1, wherein the mixed liquor is formed using a mixer under a control of the computer.

11. A system for wastewater treatment control through microorganism metabolic pathway optimization, comprising: a computer configured to: receive a user input comprising at least one of a time of a digestion of one or more pollutants and a degree of digestion of the one or more of the pollutants by microorganisms in a sludge capable of digesting the one or more of the pollutants by exercising a digestive function via one or more catabolic pathways to obtain energy and store the energy in a form of adenosinetriphosphate (ATP), wherein the sludge is mostly free of the one or more of the pollutants; store an association between how quickly an at least reactive gas dissolves within the sludge to a predetermined concentration and a degree to which the microorganisms exercise the digestive function upon encountering the one or more of the pollutants following the at least one reactive gas dissolution; determine a time during which the at least one reactive gas needs to dissolve to the predetermined concentration within the sludge based on the user input using the association; a gas generator under a control of the computer configured to generate the at least one reactive gas that is provided into the sludge; a machine under a control of the computer and comprising one of an atomizer or a pump, the machine configured to: forming a gas-dispersion return sludge by at least partially dissolving the at least one reactive gas in the sludge in the determined time to reach the predetermined concentration within the sludge; form a mixed liquor by providing the gas-dispersion return sludge for combining with a wastewater that comprises the one or more of the pollutants, wherein upon encountering the one or more of the pollutants in the wastewater, the microorganisms store an amount of the ATP during an initial time period that is dependent on the determined time and wherein the microorganisms exercise the digestive function during a further time period based on the amount of the ATP created and stored during the initial time period.

12. A system according to claim 11, wherein the predetermined concentration is comprised within a range of predetermined concentrations, the computer further configured to select the predetermined concentration from the predetermined concentration range based on the user input.

13. A system according to claim 11, wherein one of the pump and the atomizer pressurize the at least one reactive gas during the formation of the gas-dispersion return sludge.

14. A system according to claim 11, wherein the microorganisms prioritize the digestive function when the time to reach the predetermined concentration of the at least one reactive gas in the sludge is not more than 4 seconds.

15. A system according to claim 11, wherein the at least one reactive gas comprises oxygen and the predetermined concentration of the oxygen is at least 10 mg/l.

16. A system according to claim 15, wherein the at least one reactive gas further comprises trace amounts of ozone.

17. A system according to claim 11, wherein the wastewater is from a dairy farm and the gas generator and at least one of the pump and the atomizer are located on the dairy farm.

18. A system according to claim 11, wherein the wastewater is from a ship and the gas generator and at least one of the pump and the atomizer are located on the ship.

19. A system according to claim 11, further comprising: a gas velocity volume control valve at an inlet of the machine configured to control a speed with which the at least one reactive gas is provided into the pump.

20. A system according to claim 11, wherein the machine provides the gas-dispersion return sludge to a mixer under a control of the computer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1A-1B are block diagrams showing a system for wastewater treatment control through microorganism metabolic pathway optimization in accordance with two embodiments.

(2) FIGS. 2A-2B are flow diagrams showing a method for wastewater treatment control through microorganism metabolic pathway optimization in accordance with one embodiment.

(3) FIG. 3 is a flow diagram showing a routine for forming gas-dispersion return sludge and returning the gas-dispersion return sludge to the aerobic reaction vessel for use in the method of FIG. 2A-2B in accordance with one embodiment.

DETAILED DESCRIPTION

(4) Traditionally, the relationship between the amount of oxygen provided to microorganisms and the amount of pollutants in wastewater that those microorganisms can break down using the oxygen has been thought to be linear. Thus, regardless of the overall concentration of oxygen, 1DO (mg/l) has been thought to be capable of facilitating the breakdown of 1BOD or 1COD of pollutants. In particular, microorganisms used in conventional standard activated sludge techniques, where bubbling is conducted using air in bubbles of diameter around 1 mm and the supply of dissolved oxygen is low, are in a state of oxygen starvation when they encounter pollutants in waste water and are able to obtain and store cATP from the pollutants only at a very slow rate. In this state, the microorganism prioritize the anabolic pathways via the reproductive function, multiplying and producing excess sludge, which, as described above, is challenging to dispose of. In addition, the prioritizing of the reproductive function results in a slowing down of the purification of the wastewater from the pollutant.

(5) As further described below, at high oxygen concentrations achievable through the use of the system and method described below, that relationship is no longer linear, and the achievable wastewater purification effect far exceeds the effect achievable with activated sludge-based purification when oxygen remains at a level seen in nature (2-4 mg/l). This effect increases the rate at which wastewater can be purified and decreases the cost of such purification. In particular, the fast rate with which the microorganisms in sludge can be supplied with a level of a reactive gas such as oxygen that far exceeds the level seen in nature allows the microorganisms to quickly obtain and store a large amount of cATP upon initially encountering pollutants in wastewater. Having avoided oxygen starvation and having stored large amounts of cATP, the microorganisms are able to prioritize further digestion of the pollutants via catabolic pathways, thus accelerating the rate (and the degree) at which the pollutants in the water are digested.

(6) Microorganisms, after being placed in an environment with very little food or a closed environment which causes near-starvation, can, upon contact with food, exhibit advantageously their digestive abilities over their reproductive abilities. The increase in the purification ability of the microorganisms in the presence of the high level of oxygen is achieved by making the microorganisms prioritize their digestion function over their reproduction function. Microorganisms (also referred to as microbes below), such as bacteria and protozoa, prioritize their digestive function when the amount of available consumable material (such as organic pollutants) is low relative to the microorganism population. On the other hand, when the amount of the consumable material is high relative to the microorganism population, enough to satisfy the energy needs of the existing microorganism population as well as additional population, the reproductive function of the microorganisms is prioritized over the digestive function and the microorganisms asexually reproduce. In the description below, the microorganisms exhibiting their digestive and reproductive function can include aerobic microorganisms, as well as facultative anaerobic and opportunistic microorganisms. FIGS. 1A-1B are block diagrams showing a system 10 for wastewater treatment control through controlled microorganism metabolic pathway optimization in accordance with two embodiments. The system 10 in the embodiment shown with reference to FIG. 1A includes a Sedimentation Vessel (also known as a sediment pool and a grit chamber) 12, an Adjustment Vessel 14, a Mixer/Distributor 15, one or more Aerobic Reaction Vessels (also known as an aeration vessel) 16, a Sludge Sedimentation Vessel 18, a Sludge Storage Vessel 20, an Atomizer 24, and a Treated Water Processing Unit 73. The system 10 shown with reference to FIG. 1B includes a Sedimentation Vessel (also known as a sediment pool and a grit chamber) 12, an Adjustment Vessel 14, a Mixer/Distributor 15, one or more Aerobic Reaction Vessels (also known as an aeration vessel) 16, a Sludge Sedimentation Vessel 18, a Sludge Storage Vessel 20, a Pump 22, and a Treated Water Processing Unit 73, and one or more velocity control valves 136. The pump 22 could be a cavitation pump or another kind of pump. In a further embodiment, one or more of the velocity control valves 136 are also in the system 10 of FIG. 1A at the inlet and outlet of the atomizer 24.

(7) The Sludge Storage Vessel 20 and the one or more Aerobic Reaction Vessels 16 are connected by the Return Sludge Pipeway 26, constructed such that return sludge which has settled in the Sludge Storage Vessel 20 can be supplied to the Mixer/Distributor 15 and eventually to the one or more Aerobic Reaction Vessel 16. The Atomizer 24 or the Pump 22 are positioned linearly along the Return Sludge Pipeway 26. Return Sludge 35 which travels through Return Sludge Pipeway 26 is therefore acted on by the Atomizer 24 (in the embodiment of the system 10 shown with reference to FIG. 1A) or the Pump (in the embodiment of the system 10 shown with reference to FIG. 1B) and becomes gas-dispersion return sludge 36, which is in turn supplied to the Mixer/Distributor 15 and the one or more Aerobic Reaction Vessel 16 as gas-dispersion return sludge 36.

(8) The system 10 further includes an Oxygen and Ozone Generator 28 that provides at least one reactive gas 37, oxygen with a possible addition of ozone, for addition to the return sludge 35. The Oxygen Supply Pipe 30 and the Ozone Supply Pipe 32 which are connected to the Oxygen and Ozone Generator 28 are connected to one or more pipes that is part of a Return Sludge Pipeway 26 and is in the upstream (intake) side of Atomizer 24 (in the embodiment of the system 10 shown with reference to FIG. 1A) or of the Pump 22 (in the embodiment of the system 10 shown with reference to FIG. 1B).

(9) In addition, the Pump 22 includes multiple apertures 137 that connect to the oxygen supply pipe 30, the ozone supply pipe 32, and the Return Sludge Pipeway 26. The apertures 136 are in turn coupled to control valves 137. The control valves 137 coupled to the apertures that are an inlet to the pump control the speed with which the oxygen, the ozone, and the return sludge 35 enter into pump 22, thus providing an additional mechanism to provide precise control over the ratios of the reactive gases 37 and the return sludge 37 within the pump 22 and the percentage of such gases 37 within the gas-dispersion return sludge that exits the pump 22. In addition, the control valve 137 at the aperture that serves at the outlet of the pump 22 allows to control the timing and amount of the gas-dispersion return sludge 36 that exits from the pump, thus providing a further amount of control over the formation of mixed liquor 17 described below. In a further embodiment, the apertures of the atomizer 24 can similarly be coupled to control valves 136 and the entrance and exit of substances from the atomizer 24 can similarly be controller via the valves 136.

(10) For the Oxygen and Ozone Generator 28, the oxygen and ozone generator in U.S. Pat. No. 7,105,092 may be utilized. Other kinds of generators are possible. In one embodiment, the total amount of gas with produced by the Oxygen and Ozone Generator 28 includes no less than 90% of oxygen, with the concentration of ozone within the gas-dispersion return sludge 36 not exceeding 0.5 mg/L and the concentration of oxygen being more than 10 mg/L.

(11) The Return Sludge Pipeway 26 is connected only to the Mixer/Distributor 15 (and hence to the one or more Aerobic Reaction Vessels 16), and is therefore not connected to Sedimentation Vessel 12, Adjustment Vessel 14, and Sludge Sedimentation Vessel 18. The technological reason for this is discussed below.

(12) As further described below beginning with reference to FIGS. 2A-2B, the Wastewater for Treatment (raw sewage) 11 enters Sedimentation Vessel 12 where grit and other inorganic solids settle and are separated out. From the Sedimentation Vessel 12, the Wastewater 11 flows into Adjustment Vessel 14 where the load and conditions of the inflowing raw sewage are adjusted, such as through automatic dilution, though other adjustments are possible, and organic solids present in the wastewater are solubilized by anaerobic microorganisms.

(13) From the Adjustment Vessel 14, the Wastewater 11 flows into the Mixer/Distributor 15. The Mixer/Distributor 15 (also referred to as Mixer in the description below) receives wastewater 11 supplied from the Adjustment Vessel 14 and also receives gas-dispersion return sludge 36 supplied from via the Return Sludge Pipeway 26, mixes them together and supplies a mixture (a mixed liquor 17) of gas-dispersion return sludge 36 and wastewater 11 to the one or more Aerobic Reaction Vessels 16. From there, aeration by bubbling using air as a reactive gas becomes unnecessary due to the reactive gas contained in gas-dispersion return sludge 36, which supplies dissolved oxygen (DO) to the Aerobic Reaction Vessel 16 (and initially to the Mixer 15). The Mixer 15 can include such parts as necessary for carrying out this function, such as a vessel for temporarily holding the mixed liquor 17, connections to the Aerobic Reaction Vessels 16, and one or more pumps for pumping the mixed liquor 17 to the one or more Aerobic Reaction Vessels 16. When there are multiple Aerobic Reaction Vessels 16, the Mixer/Distributor 15 can be managed appropriately to distribute to each of them in accordance with the treatment capacity of each. In an installation with only one Aerobic Reaction Vessel, the Mixer/Distributor 15 can be entirely omitted, with the wastewater 11 and the gas-dispersion return sludge 36 being pumped directly into the Aerobic Reaction Vessel 16, where they form the mixed liquor 17.

(14) As further described below, the microorganism flora in the gas dispersion return sludge 36 has been activated by the oxygen (possibly with a trace of ozone) supplied by the gas generator 28 and dissolved within the gas-dispersion return sludge to a high level within a short time by either the pump 22 or the atomizer 24 In one embodiment, the level of dissolved oxygen achieved within the short time is between 10 mg/1-50 mg/l oxygen concentration achieved within the 2-4 seconds, though in a further embodiment, other concentration and time values are possible. The time necessary for the dissolution depends on the intensity of the operation of the pump 22 or the atomizer 24. The gas-dispersion return sludge 36 is either completely devoid of, or has an extremely low level of organic pollutants (and other pollutants that can be digested to obtain energy) that can be digested by the activated microorganisms. At such conditions, once activated by the quickly-dissolved level of the at least one reactive gas 27, the microorganisms have been empirically shown to prioritize the catabolic pathways by exercising their digestive function at the expense of their reproductive function, even though the microorganisms have no way to capitalize on the function at that point in time due to a complete or almost complete absence of digestible material. Upon the gas dispersion return sludge 36 being mixed with the wastewater that includes digestible organic pollutants (and other pollutants, such as ammonia, that can be digested to produce energy), the microorganisms that have previously been starved of digestible material start exhibiting the digestive function at an elevated rate compared to a suppressed reproductive function. In particular, during an initial period of encountering the pollutants within the wastewater 11, the microorganisms obtain and store enough of the cATP through the digestion of the pollutants that the microorganisms that in a subsequent time period they can continue to prioritize the digestive function. The length of the initial period can be dependent on multiple parameters, such as temperature of the wastewater 11 and the kinds of pollutants being digested, though other parameters that affect the length of the initial period are also possible. This prioritization in turn allows to reduce the time during which the pollutants are digested and the degree of their digestion (with the degree being the percentage of the digestable pollutants present in the wastewater 11 that gets digested). Further, as the time during which the level of the dissolved oxygen (and optionally ozone) reaches the necessary level is controllable through controlling intensity of operation of the atomizer 24 or the pump 22, thus allowing to control the extent to which the digestive function is prioritized over the reproductive function, which in turn allows to control the time necessary for the digestion of the pollutants and the degree of the digestion of the pollutants. as described further below with reference to equation (3) and (4), the byproducts of the digestion and the oxygen requirements for the digestion differ from what the byproducts and the oxygen requirements under normal conditions. The prioritizing of the digestive function over the reproductive function continues within the one or more Aerobic Reaction Vessels 16 until the energy requirements of the microorganism have been satisfied, at which point they can also start exhibiting the reproductive function to produce sludge 21 if any organic pollutants (or other absorbable pollutants) remain in the mixed liquor 17 undigested. Upon complete or substantially complete consumption of the digestible or absorbable pollutants within the mixed liquor, at least a portion of the microorganisms (such as the majority or all of the microorganisms within the mixed liquor) enter a dormant state (in which biochemical processes within the microorganisms are substantially slowed down or halted) due to a lack of further digestible material.

(15) Upon completion of a hold time, a time that can be experimentally determined to be adequate for the completion of the digestion (and possibly consumption through the reproductive function) of the organic pollutants (and other pollutants, such as ammonia, on which the functions can be exhibited) in the mixed liquor 17, the mixed liquor 17 is pumped from the Aerobic Reaction Vessels 16 to the Sludge Sedimentation Vessel 18, where the mixed liquor 17 is separated into a supernatant and a sludge 21. The sludge 21 is collected in Sludge Storage Vessel 20, and as described further below, is returned to Aerobic Reaction Vessel 16 in the form of gas-dispersion return sludge 36, for cyclical reuse. In a further embodiment, the system 10 can omit the Sludge Storage Vessel 20, and the exit side of Sludge Sedimentation Vessel 18 and the Mixer/Distributor 15 are connected to the Return Sludge Pipeway 26.

(16) The supernatant is pumped out from the Sludge Sedimentation Vessel 18 as Treated Water 72, which in turn is pumped into a Treated Water Processing Unit 73, where the water is further processed. Such processing can include sterilization, such as described in U.S. Pat. No. 10,287,194, filed issued May 14, 2019, to Ohki et al., the disclosure of which is incorporated by reference, though other ways to sterilize the Treated Water 73 is possible. Other processing can be done at the unit 73. While the unit 73 is shown as a single physical structure with reference to FIGS. 1A and 1B, the unit 73 could also be made up of multiple, spatially separated components. The water processed by unit 73 is expelled from the system as Purified Water 74, now being suitable for use, such as drinking.

(17) Additionally, the excess sludge is pumped out of the wastewater management system as Excess Sludge 27.

(18) At least some portion of the sludge from Sludge Sedimentation Vessel 18 passes through the Return Sludge Pipeway 26 in the form of Return Sludge 35, entering the Atomizer 24 (in the embodiment of the system 10 shown with reference to FIG. 1A) or the Pump 22 (in the embodiment of the system 10 shown with reference to FIG. 1B). Before the entrance point of the Atomizer Pump 24 or the Pump 22, pure oxygen gas or pure oxygen gas with trace amounts of ozone are mixed into Return Sludge 35, forming gas-dispersion return sludge 36.

(19) The creation of the gas-dispersion return sludge 36 is made possible by the use of the Atomizer 24 (in the embodiment of the system 10 shown with reference to FIG. 1A) or the Pump 22 (in the embodiment of the system 10 shown with reference to FIG. 1B) that operate to dissolve the at least one reactive gas under an increased pressure (at least 0.05 megapascals higher than the prevailing water pressure of sewage). In particular, a gas-liquid mixture (a mixture of the at least one reactive gas 37 with the Return Sludge 35) is formed within the Return Sludge Pipeway 26 and is pumped to the Atomizer 24 (in the embodiment of the system 10 shown with reference to FIG. 1A), which has the function of churning and mixing the aforementioned gas-liquid under high pressure (approximately 0.0981-5.394 MPa (1-55 kg/cm 2)), then employing either cavitation or 20-12,000 kHz ultrasound respectively or both simultaneously to induce ultra-fine bubbles in the gas-liquid mixture of diameter from 1 nm-30,000 nm, further causing oxygen radicalization and hydroxyl radicalization. A portion of the ultra-fine bubbles dissolve within the gas-dispersion return sludge, raising the level of the dissolved oxygen to the critical threshold of at least 10 mg/l (with the concentration of ozone, if ozone is utilized, being 0.01-0.5 mg/l), and a portion is stored with the sludge 36 as ultra-fine bubbles. Thus, the Atomizer 24 can instantaneously render the desired quantity of reactive gas 37 into ultra-fine bubbles, rapidly dissolving a portion of the reactive gas, then disperse, immobilize and store the excess in a liquid in the form of ultra-fine bubbles. Increasing the level of the dissolved oxygen to the critical threshold (at least 10 mg/l) has been empirically shown to activate the microorganisms within the sludge 36, removing them from the dormant state. While the microorganism are activated at this point and are ready to digest organic and other digestible pollutants (and are prioritizing their digestive function over their reproductive function), the level of digestible pollutants (or other digestible organic materials) within the gas-dispersion return sludge 36 is either at zero or close to zero (at a level insufficient to satiate the prioritized digestive function of the microorganism), and thus the microorganisms are forced into a state of extreme starvation.

(20) In one embodiment, the Atomizer 24 can be the OHR Mixer sold by OHR Laboratory Corporation of 536-1, Noda, Irumashi, Saitama 358-0054 Japan. In a further embodiment, other commercially available or proprietary Atomizers 24 can be used.

(21) Similarly, in the embodiment of the system 10 shown with reference to FIG. 1B, instead of entering the Atomizer 24, the mixture of the return sludge 35 and the at least one reactive gas 37 enters a Pump 22. In one embodiment, the pump can be a cavitation pump. Cavitation is the formation of vapor cavities in a liquid. In pumps, cavitation is caused by an impeller of the pump moving through a liquid, with low-pressure areas being formed as the liquid accelerates and moves past the blades, causing the liquid to vaporize and form small bubbles of gas. While cavitation in most cases is undesirable as cavitation is damaging to the components of the pump, the Pump 22, while subject to increased wear due to cavitation, takes advantage of the cavitation effect to help dissolve-at least one reactive gas 37 within the return sludge to create gas-dispersion return sludge 36. In particular, the rotation of the impeller of the Pump 22 is fast enough to slice the formed bubbles into multiple smaller bubbles, thus forming ultra-fine bubbles of the 1 nm-30,000 nm diameter. The Pump 22 operates feunder a high pressure, which facilitates the dissolution of the at least one reactive gas 37 within the return sludge 35. In one embodiment, the pressure inside the pump 22 is between 0.0981 MPa and 5.394 MPa, though other values of pressure are also possible. In a further embodiment, a pump 22 could use a mechanism of action other than cavitation for the creation of the ultra-fine bubbles.

(22) The gas-dispersion return sludge 36 is returned solely to Mixer/Distributor 15 and the one or more Aerobic Reaction Vessels 16, and is not returned to Sedimentation Vessel 12, Adjustment Vessel 14, or Sludge Sedimentation Vessel 18. The returned quantity of gas-dispersion return sludge 36 is unitarily controlled and unitarily managed to maximize the sum total reduction of carbon dioxide, the reduction in treatment costs, and the reduction in energy usage of the entire wastewater treatment system. Because the wastewater treatment capacity of-one or more Aerobic Reaction Vessels 16 is dramatically increased, the Aerobic Reaction Vessel 16 can be made very small.

(23) Due to processing by the Atomizer 24 or the Pump 22 and being subsequently provided to the one or more Aerobic Reaction Vessels 16, the microbe flora within gas-dispersion return sludge 36 becomes activated by the oxygen (and possibly ozone) that the microbes receive. For example, when the gas-dispersion return sludge enters Aerobic Reaction Vessel 16 (or if the Mixer/Distributor 15 is employed, the Mixer 15), the activated microbes have been brought to a state of extreme near-starvation, so that between their reproductive function and their digestive function, they autonomously prioritize digestion over reproduction. Thus, the provision of the high level of oxygen (or oxygen with the trace of ozone) allows the operator to individually control and manage catabolic and anabolic processes of the microorganisms via the reproductive and digestive functions of the microbe colonies, prioritizing the digestive function of the microbes over the reproductive function. In the present application, the term reproductive function of the microbe flora is defined as the function by which the microbes absorb as food organic matter contained in wastewater 11, the microbes grow, and then reproduce, such that the organic matter becomes isolated as a mass of matter and microbes, thus purifying the wastewater. The digestive function of the microbe colonies is defined as the function by which the microbes absorb as food organic matter contained in wastewater, then break it down and digest it to gain energy which sustains their activity and their life processes.

(24) The high activation of the microorganisms is particularly pronounced when the concentration of oxygen within the Aerobic Reaction Vessel 16 reaches a particular critical threshold, with the presence within the mixed liquor 17 of at least 10% of volume of the gas-dispersion return sludge 36 that has at least 10 mg/l of dissolved oxygen (a level that can be achieved through the use of the Atomizer 24 or the Pump 22). Once that threshold is reached, 1DO (mg/l) is enough for breaking down more pollutants than what would be included in 1BOD or 1COD when the dissolved oxygen within the Aerobic Reaction Vessel 16 is at a lower level. At these conditions, the amount of pollutants degraded by the microorganisms within the Aerobic Reaction Vessel 16 has experimentally been shown to exceed 20 times the amount of pollutant degraded by the same microorganisms than when the concentration of oxygen is at levels close to those occurring in nature (2-4 (mg/l). At a differing concentration of oxygen, the critical threshold of the gas-dispersion return sludge 36 that needs to be added to the Aerobic Reaction Vessel 16 would change proportionally. The knowledge of this effect can be used to calculate with great precision an amount of the gas-dispersion return sludge 36 that is necessary for purification of a particular amount of wastewater 11, allowing to reduce the amount of unnecessary Excess Sludge 27 produced. Likewise, knowing the volumes of the gas-dispersion return sludge 36 and the volume of wastewater 11 that need to be handled can allow to properly size the components of the system 10, reducing waste and cost of creating the system 10. The exact ratio of the volumes of the gas-dispersion return sludge 37 to wastewater 11 can be set based on the degree of the contamination of the wastewater 11 being treated. For example, the volume of gas-dispersion return sludge 36 being 10% of volume of wastewater 11 to be treated is sufficient when the wastewater 11 comes from the bilge of a ship. However, the volume of gas-dispersion return sludge 36 may need to be much higher, such as 40% of the volume of the wastewater 11, when the wastewater 11 comes from a sewage plant or another highly polluted source.

(25) As the formation of ultra-fine bubbles plays an important role in the activation of the microorganisms, additional explanation is provided regarding the formation and use of the bubbles below. Regarding the slowing effect on the velocity at which bubbles rise within a liquid which can be achieved by producing bubbles which are ultra-fine, bubbles with diameter of around 30 ?m rise within a liquid at approximately 1 m/hr, and at a diameter of around 1 ?m they rise at less than 0.005 m/hr (Stokes' Law for Spherical Bubbles). With this range of velocity, bubbles remain within the liquid for long enough that they can immediately and at the required position replace dissolved oxygen which has been consumed by the biochemical reaction with the pollutant substances in the wastewater to be treated, and furthermore, because the bubbles can be dispersed in ultra-fine bubble form, uniformly and in great quantity, and therefore in the same places where oxygen has been consumed, a bubble storage function is also achieved.

(26) In this way, the desired reactive gases including oxygen or oxygen and ozone can be supplied and stored with extremely long duration, with neither surplus nor shortage, thereby shortening and stimulating the biochemical reaction, and also allowing that the supply within the time period required to carry out the biochemical reaction need not necessarily be continuous but can be intermittent.

(27) As mentioned above, the Atomizer 24 or the Pump 22 is employed to disperse gas into liquid in the form of ultra-fine bubbles. To render bubbles to an ultra-fine size and blend the ultra-fine bubbles into liquid, mechanical agitation and cutting are insufficient to achieve the nano level, and only when the velocity of the two-phase flow of the vapor-liquid is increased through pressurization, and a synergistic effect with the vortex churning of the liquid is generated using cavitation and ultrasound, that the bubbles are broken down to ultra-fine state and blended into the mixture as ultra-fine bubbles. For the gas to be dissolved and remain in dissolved state, pressure conditions are of key importance, and higher pressures are known to be more advantageous. Taking all these factors into account, the range of pressure chosen for the Atomizer 24 or the Pump 22 is from 0.0981 MPa-5.394 MPa (1-55 kg/cm 2).

(28) While in a simple return process for activated sludge (with zero addition of reactive gas), operating in low pressure ranges helps to avoid destroying the microorganisms which exist in the activated sludge, maintaining the pressure low no longer makes sense when reactive gas is added to the sludge. The reason to strive for the highest pressure that can be practically achieved (approximately 5.5 MPa), is to effectively utilize, in the oxidation and decomposition process of sludge employing reactive gas including high density ozone, a synergistic oxidation and decomposition effect between the actions of cavitation and ultrasound, which under high pressure cause the oxidation and breakdown of ozone itself, and the functioning of O radicals and OH radicals. With the large-capacity wastewater treatment employing the activated sludge method 40 and the system 10, care has been taken to choose frequencies of ultrasound which can be used easily and economically, and so at low pressure ranges a frequency of 20 kHz was chosen, and for high pressure ranges (approximately 5.5 MPa) a frequency of 12,000 kHz was chosen. In a further embodiment, other frequencies in the 20 kHz-12,000 kHz range are possible.

(29) For the Oxygen and Ozone Generator 28, an ozone generator or similar may be used to regulate the supply of oxygen and the generation of ozone. For example, by employing an ozone-generating element comprising an electrode mounted to a boss fashioned from a dielectric substance, and a high-frequency high-voltage power source which applies a high-frequency alternating current to the ozone-generating element while supplying an oxygen-rich gas to the ozone-generating element, and adjusting the quantity of ozone generated by using a regulator to control the voltage and/or the frequency of the power source, it becomes possible to effect an oxygen/ozone cycle generator which regulates the amount of oxygen and ozone supplied, to cope with fluctuations in the quality and load of sewage for wastewater treatment due to morning, daytime or nighttime, or due to either dry weather or rainy weather, or to cope with processes based mainly on the supply of oxygen and with processes based mainly on oxidation and decomposition by ozone. For the reactive gas including oxygen to be supplied, oxygen-enriched air or pure oxygen are both acceptable. The supplied gas may also be pumped as is, with zero ozone generation. Of course, the operation of the oxygen/ozone cycle generator may also be suspended. Further, while the Oxygen and Ozone generator 28 is represented as a single unit, in a further embodiment, the system 10 could include multiple generators 28, one generator 28 providing ozone and another generator providing oxygen, with the gases provided by both generators being provided into the Return Sludge Pathway 26 to be mixed with the return sludge 35.

(30) In the activated sludge process, the microorganisms which effect the biochemical reaction are returned to the wastewater intake side with a portion of the sludge (return sludge) such that the microorganisms are utilized cyclically. If the wastewater 11 to be treated includes high densities of organic substances, and accelerating the microbial biochemical reaction is therefore necessary, then maximizing the quantity of oxygen dissolved in the wastewater 11 or replenishing dissolved oxygen rapidly according to the amount of dissolved oxygen which is consumed is desirable. The system 10 performs favorably in this respect, employing the Atomizer 24 or the Pump 22, to infuse with the required amount of oxygen gas (or oxygen with the trace of ozone) the water which carries the return sludge back to Aerobic Reaction Vessel 16. The microbial biochemical reaction is accelerated dramatically due to the Atomizer 24 or the Pump 22 supplying a plentiful amount of oxygen (or oxygen with a trace of ozone) in a dissolved state and in the form of ultra-fine bubbles in an extremely short time.

(31) Because ultra-fine bubbles, as previously described, require a very long time to float to the surface of Aerobic Reaction Vessel 16, during the time which it takes them to float to the surface of Aerobic Reaction Vessel 16, the ultra-fine bubbles in Aerobic Reaction Vessel 16 are dispersed and stored in the form of ultra-fine bubbles, and continuously replenish the dissolved oxygen. By maintaining a high quantity of dissolved oxygen in Aerobic Reaction Vessel 16, significant acceleration of the microbial biochemical reaction becomes possible. Due to the effect of the microbial biochemical reaction within Aerobic Reaction Vessel 16, a portion of the organic matter in the wastewater is digested, releasing carbon dioxide and water, and a portion of the organic matter is consumed by activated sludge microorganisms; the microorganisms multiply, and the activated sludge is generated. In this case, by adding not only oxygen to the wastewater, but by optionally also adding and employing trace amounts (e.g. up to 0.01-0.5 mg/1=ppm) of ozone, greater activation of the microorganisms which carry out the microbial biochemical reaction becomes possible.

(32) Further, under the conditions that are created in the system 10 of FIG. 1, the digestive function exhibited by the microorganisms while in the aerobic reaction vessels occurs via different biochemical pathways (and consequently via different chemical reactions) than under natural conditions. In particular, in addition to water, at least some of the biochemical pathways result in production of inert compounds, such as amorphous carbon or diatomic nitrogen (N.sub.2). For example, under the conditions created in the system 10, digestion of acetic acid proceeds in accordance with the following equation:
CH.sub.3COOH.fwdarw.2C+2H.sub.2O+Energy(3)

(33) Compared to equation (1) given above, the chemical reaction of equation (3) that takes place under the conditions in the Aerobic Reaction Vessels 16 created in system 10 requires no external oxygen, thus allowing the reaction to proceed until the energy requirements of the microorganisms satisfied, making exhibition of the reproductive function possible after that point. Further, unlike the reaction given in equation (1), the reaction does not produce carbon dioxide, but instead produces inert amorphous carbon that can be easily removed from the mixed liquor 17. While this reaction does not use oxygen, the same microorganisms in the mixed liquor 17 can also perform aerobic digestion of other compounds. For example, digestion of ammonia takes place via a different chemical reaction than what is given in equation (2), but is still aerobic. Thus, under the conditions created in the system 10, in the Aerobic Reactions Vessels 16, the digestion of ammonia takes place in accordance with the following equation:
4NH.sub.3+3O.sub.2=2N.sub.2+6H.sub.2O+Energy(4)

(34) This reaction of equation (4) uses only 3 molecules of diatomic oxygen compared to seven molecules used in the reaction of equation (2)), allowing the oxygen within the ultra-fine bubbles within the mixed liquor 17 to sustain the reaction longer. Further, instead of the nitrogen dioxide produced in equation (2), the reaction of equation (4) produces diatomic nitrogen, which does not pose the same environmental concerns as nitrogen dioxide. Similar reactions can also take place with compounds that include phosphorous (such as phospholipids) and compounds that include sulfur. Likewise, similar reactions can take place with other biodegradable materials including cellulose and other carbohydrates, fats, and oils, and different kinds of protein. Overall, under the conditions created in the Aerobic Reaction Vessels 16, the microorganisms prioritize (if not switch entirely) using the biochemical reaction pathways for digesting multiple, if not all, pollutants that consume less oxygen and that produce different end products than the biochemical pathways for digesting the same pollutants employed under conditions found in nature. Further, at least some of the biochemical pathways utilizing less oxygen also may occur faster than the pathways for degrading the same pollutants that utilize more oxygen.

(35) In one embodiment, the components of the system 10 described above can be controlled independently of each other. In a further embodiment, the system 10 includes a Controller 39 that is interfaced, such as via a wired or a wireless connections, to at least the Sludge Sedimentation Vessel 20, the Oxygen and Ozone generator 28, and the Atomizer 24 (in the embodiment of the system 10 shown with reference to FIG. 1A) or the Pump 22 (in the embodiment of the system 10 shown with reference to FIG. 1B), and the control valves 136 on the Pump 22 (or the Atomizer 24 if the valves are used on the Atomizer 24). The Controller 39 can also be similarly interfaced to other machines of the system 10. The Controller 39 can receive from the operator of the system 10 input (also referred to as user input) based on which the controller 39 determines and controls actions of the other components of the system 10. For example, the user input can include the amount of gas-dispersion return sludge 36 that is to be delivered to the Aerobic Reaction Vessel 16 and control the Sludge Sedimentation Vessel, the Oxygen and Ozone Generator 28, the Pump 22 or the Atomizer 24 to deliver the desired amount of the gas-dispersion return sludge 36. Alternatively, the controller 39 can receive from the operator a characteristic of the wastewater treatment, such as a degree of the wastewater treatment desired by the operator (such a percentage of the pollutants to be digested), a wastewater treatment time desired by the operator, and a desired wastewater treatment capacity, and determine the amount of the gas-dispersion return sludge 36 to be delivered to the Aerobic Reaction Vessel 16 and any other parameters of the treatment necessary to achieve the desired characteristic. The determined amount can then be delivered under the control of the Controller 39 and other components of the system 10 similarly controlled to determine the desired parameters. In particular, when the time of the treatment, the degree of the treatment, or both are included as part of the user input, in addition to the amount of the gas-dispersion return sludge 37 that needs to be delivered, the controller 39 determines the time during which the oxygen concentration needs to be raised to the threshold of at least 10 mg/l within the gas-dispersion return sludge to achieve the desired time or degree (or both) of treatment and controls the intensity of operation of the atomizer 24 and the pumps 22 (including controlling the valves 136) to achieve the desired results. For example if a higher degree of treatment and a shorter treatment time is specified in the user input, the time to achieve the threshold oxygen concentration could be set at in the gas-dispersion return sludge could be set at 2 seconds. If a slower time frame or a lesser degree of treatment is provided as part of the user input, the controller could set the time to achieve the threshold oxygen concentration of at least 10 mg/l at 3 or 4 seconds (or another value between 2 seconds or 4 seconds). Similarly, the amount of oxygen (and ozone) introduced into the sludge 35 can be varied by the controller 39 by controlling the oxygen and ozone generator 28 and the control valves 136 on the pump 22 (or the atomizer 24). Thus, the controller 39 can determine the amount of oxygen (and optionally ozone) to be provided to the pump 22 or the atomizer 24 based on the time of treatment and the degree of treatment (or both) provided as part of user input, and increase the provided amount (by controlling the generator 28 and the valves 136) if a quicker treatment and higher degree of the digestion of the pollutants in the wastewater 11 is desired. In a still further amount, the user input include if and how much the user would like additional sludge 35 to be produced; if a significant amount of sludge 35 is to be produced, the computer can set the time that the oxygen takes to reach the critical concentration of at least 10 mg/l to be longer than 4 seconds. The Controller 39 can be a computing device, such as a personal computer, a smartphone, a laptop, a tablet, though other kinds of computing devices are possible. The Controller 39 can include components conventionally found in general purpose programmable computing devices, such as a central processing unit, memory, input/output ports, network interfaces, and non-volatile storage, although other components are possible. The central processing unit can implement computer-executable code which can be implemented as modules. The modules can be implemented as a computer program or procedure written as source code in a conventional programming language and presented for execution by the central processing unit as object or byte code. Alternatively, the modules could also be implemented in hardware, either as integrated circuitry or burned into read-only memory components. The various implementations of the source code and object and byte codes can be held on a computer-readable storage medium, such as a floppy disk, hard drive, digital video disk (DVD), random access memory (RAM), read-only memory (ROM) and similar storage mediums. Other types of modules and module functions are possible, as well as other physical hardware components.

(36) The Controller 39 can be controlled by the operator on-site or remotely. For example, the Controller 39 can be interfaced to an Internetwork, such as the Internet or a cellular network, and a user device (such as a smartphone though other user devices are possible) also interfaced allows to command the Controller 39 remotely, and provides remote control of the system 10 to the operator.

(37) Other embodiments of the Controller 39 are also possible.

(38) When the system 10 has not been run recently, there may not always gas-dispersion return sludge 36 available to be added to the Aerobic Reaction Vessel 36 and provide the aerobic microorganisms necessary to conduct the aerobic reaction to the Aerobic Reaction Vessel. In such a situation, the system 10 may utilize seed sludgesludge 21 that is input into the system 10, such as into the Return Sludge Pipeway 26, from an external source, such as another wastewater treatment system, though other external sources are possible. By being processed by the Atomizer 24 (or the Pump 22) and the Oxygen and Ozone Generator 28, the seed sludge is turned into the gas-dispersion return sludge 36 and can then be provided to the Aerobic Reaction Vessel 16 to be used for the treatment of the wastewater 11. As the microorganisms present in activated sludge 21 differ significantly based on the geographic origin of the wastewater 11 from which the sludge 21 is created, the seed sludge introduced into the system 10 is selected based on the geographic location of the wastewater from 21 from the seed sludge originates. Preferably, the seed sludge is from the same or proximate geographic location as the wastewater 11 being processed by the system 10 to avoid an introduction of exogenous microorganisms that can negatively impact the aerobic reaction.

(39) The system 10 can be created from most existing water treatment facilities by retrofitting certain portions of the system 10 onto existing equipment. In particular, the Atomizer 24 or the Pump 22, and the oxygen and ozone generator 28 can be retrofitted into an existing wastewater treatment plant, allowing for widespread use of the system 10 and the method described in this application. Similarly, the system 10 of FIGS. 1A and 1B can even be retrofitted into environments where activated-sludge-based purification is not even traditionally employed. For example, the system 10 (of FIG. 1A or 1B) could be installed on a bilge of a ship, with the bilge water of the ship (including ballast water) being ran through the ship's system 10 continuously while the ship is at sea to decrease the number of pollutants (including dead animals and their waste) inhabiting the bilge water. Alternatively, or in addition to installing the system 10 on the ship, the system 10 (of FIG. 1A or 1B) could be installed at a port, with the ship's bilge water being transferred into a tank that connects to the system 10 when the ship docks at the port, with the bilge water being cleaned by the system 10 before either being returned to the ship or disposed of in another way. Similarly, the system 10 (of FIG. 1A or 1B) can be installed on in a dairy farm lagoon, with the dairy farm manure-contaminated water being cleaned through the use of the system 10, thus inhibiting growth of anaerobic bacteria in the water and reducing odor, ground water pollution, methane gas emissions, and other undesirable effects of dairy farm water contamination.

(40) As described above, exercising control over the time the oxygen (and optionally ozone) take to dissolve within the gas-dispersion return sludge 36 to a reach a critical concentration, the concentration reached during that time, and the amount of the gas-dispersion return sludge 36 used to form the mixed liquor allows the operator to exercise increased control over the wastewater purification. In particular, these parameters determine whether the microorganisms exhibit exclusively the digestive function, or upon acquiring the necessary energy, in the presence of additional pollutants and oxygen, can proceed to also exhibit the reproductive function and produce the sludge 21. FIGS. 2A-2B are flow diagrams showing a method 40 for wastewater treatment control through microorganism metabolic pathway optimization in accordance with one embodiment. The method can be implemented using the system 10 of FIG. 1A or 1B. Optionally, if no gas-dispersion return sludge 36 is present in the Aerobic Reaction Vessel at the start of the execution of the method 40, seed sludge is added to the system 10, is converted into gas-dispersion return sludge 36, and is provided into one or more of the Aerobic Reaction Vessels, as described above with reference to FIGS. 1A-1B (step 41). The load of wastewater 11 to be treated is determined, the time during which the oxygen concentration in the gas-dispersion return sludge 36 needs to reach the critical concentration of at least 10 mg/l (and optionally the exact concentration the oxygen needs to reach during that time), the amount of gas-dispersion return sludge 36 to be delivered to the Aerobic Reaction Vessel 16 are determined (step 42). The determination of the amount of the gas-dispersion return sludge 36 can be done based on the load as well as other desired characteristics of the wastewater treatment, such as the degree of the purification and the speed of the treatment, though other characteristics are possible. Another one of the characteristics is whether the goals of the wastewater treatments include only digestion of the pollutants (organic and other degradable pollutants such as ammonia) via the digestive function or whether some creation of additional sludge 21 is desired. Thus, if the goal of the wastewater treatment is pure digestion of the organic pollutants (and other pollutants that can be digested to produce energy, such as ammonia) with creation of minimum to no sludge 21, the ratio of the volume of the gas-dispersion return sludge 36 to the volume of the wastewater 11 is going to be greater than if creation of at least some sludge 21 is desirable. However, as some amount of the sludge 21 is necessary for subsequent purification cycles, the ratio of the volume of the gas-dispersion return sludge 36 to the volume of the wastewater 11 can be decreased, allowing the microorganism to exhibit their reproductive function following the satiation of the digestive function. The levels of pollutants (organic and other digestible pollutants) within a wastewater 11 can vary with time even in the same location. These levels can also vary based on the source of the wastewater 11 (and hence the geographic location from where the wastewater 11 originates). Similarly, the digestive and reproductive abilities of the microorganism flora vary depending on which strains of the microorganisms that make up the flora in the sludge 36, with different strains being present in different geographic regions. Further, the exact levels of dissolved reactive gas within the gas-dispersion return sludge 36 can affect the digestive ability of the microorganisms within the sludge 36 and thus the amount of the sludge 36 required to achieve purification goals. Due to the variabilities associated with the different geographic locations and levels of reactive gases, the optimum amount of sludge for a particular purpose can be determined experimentally, as further described below. For the purpose of eliminating as much as of the organic pollutants as possible while producing minimum amount of sludge, the ratio in the mixed liquor 17 of volume of the gas-dispersion return sludge 36 (having at least 10 mg/l of dissolved oxygen) to the volume of the wastewater 11 of at least 10% has generally proved sufficient, with more than 10% being necessary when the wastewater is particularly contaminated, as described above. Similarly, if the user input specifies a short treatment time and a high degree of digestion of the pollutants and thus a prioritization of the digestion function is necessary, the time during which the oxygen needs to reach the critical threshold of at least 10 mg/l in the gas-dispersion return sludge is set in the interval of 2 seconds to 4 seconds to have the microorganisms prioritize the digestive function. The time can further be shortened and the degree of digestion increased through raising the oxygen levels to higher than just 10 mg/l in the gas-dispersion return sludge. On the contrary, if a significant generation of the sludge 35 is desired in addition to digestion of the pollutants, the time to reach the critical concentration of at least 10 mg/l can be made longer than 4 seconds.

(41) Optionally, if there is an opportunity for physically setting up or changing the set-up of the equipment used for processing of the wastewater 11 (such as the system of FIGS. 1A-1B), the parameters of the equipment necessary for processing a particular wastewater load, such as the size (though other parameters are also possible) can be determined and optionally implemented in accordance with the determination (step 43). This determination can be particularly important when the equipment is being set up for the first time in an environment where activated-sludge-based purification is not traditionally used, such as on a ship, in a port, or on a dairy farm.

(42) The wastewater 11 enters Sedimentation Vessel 12 where grit and other inorganic solids settle and are separated out (step 44). Subsequently, the wastewater 11 enters Adjustment Vessel 14 where the load and conditions of raw sewage 11 are adjusted and solid organic material is solubilized by anaerobic microorganisms (step 45).

(43) Next, the wastewater 11 flows, possibly via a mixer/distributor 15 if one or more of them are part of the system 10, into one or more Aerobic Reaction Vessels 16, where the wastewater 11 (raw sewage) is added to gas-dispersion return sludge 36 and blended to form mixed liquor 17 (if the mixer/distributor is involved, the mixed liquor 17 forms within the mixer-distributor 15 and is provided to the one or more Aerobic Reaction Vessels 16 where the majority of the biochemical (aerobic and other kinds of digestion) consumption of organic pollutants (and other degradable pollutants) takes place) (step 46). From there, if any aeration by bubbling using air as a reactive gas was previously performed, such aeration becomes unnecessary due to the reactive gas contained in gas-dispersion return sludge 36. Dissolved oxygen (DO) (possibly with traces of ozone) is supplied to the Vessels 16 by the gas-dispersion return sludge 36 and organic solids left undissolved after step 45 are oxidized; at the same time biochemical treatment by aerobic microbe flora occurs, with the organic (and other digestible) pollutant substances dissolved in the wastewater 11 being digested to water (H.sub.2O) and other byproducts, such as inert compounds such as amorphous carbon or diatomic nitrogen (N.sub.2), which can be easily removed. If the digestive function of the microorganisms has been satisfied and exhibition of the reproductive function is possible, some of the pollutants can be immobilized as additional sludge 21 via the exhibition by the microorganisms of their reproductive function (step 47). Following the completion of the consumption of the organic pollutants via the digestive and possibly the reproductive function, the microorganisms enter the dormant state.

(44) Through the action of the Atomizer 24 or the Pump 22, and the Oxygen and Ozone Generator 28, and possibly the valves 136, the quantity of dissolved oxygen that is raised within a short time (2-4 seconds) in gas-dispersion return sludge 36 to a critical level (at least 10 mg/l) that activates the microbe flora within the gas-dispersion return sludge 36 from the dormant state. While the microorganisms are activated at this point and are ready to digest the organic and other pollutants (and are prioritizing the digestive function over the reproductive function) and catabolism over anabolism, the level of the organic pollutants (and other pollutants which can be digested to extract energy) is either at zero (with the pollutants having previously been entirely consumed at the one or more Aerobic Reaction Vessels) or close to zero (at a level insufficient to satiate the prioritized digestive function of the microorganisms), and thus the microorganisms are forced into an extreme state of near-starvation. The activated microbe flora which exists within gas-dispersion return sludge 36 is supplied to Mixer/Distributor 15, if present in the system 10, and the activated microbe flora is blended with wastewater 11 by the Mixer/Distributor 15 to form the mixed liquor 17, which is supplied to the one or more Aerobic Reaction Vessels 16 (or if the system 10 does not include the Mixer/Distributor 15, the mixed liquor 17 is formed within the Aerobic Reaction Vessel 16). Within the Aerobic Reaction Vessels, the microorganisms continue to autonomously prioritize their digestive function over their reproductive function. The efficiency ratio of oxygen (DO) utilization in the digestive function of the microbe flora becomes extremely heightened. As a result, the activated microbe flora in the one or more Aerobic Reaction Vessels 16, becomes capable of purifying far more organic matter per 1DO than the typically defined quantity for the activated sludge method of 1BOD or 1COD.

(45) Next, the mixed liquor 17 progresses to Sedimentation Vessel 18, settles inside Sedimentation Vessel 18 and is separated into sludge 21 and supernatant (step 48). The settled sludge 21 is collected in Sludge Storage Vessel 20 (step 49), and is returned to Aerobic Reaction Vessel 16 in the form of gas-dispersion return sludge 36, for cyclical reuse (step 50), as further described below with reference to FIG. 3.

(46) Excess sludge 27 is expelled from the Sludge Storage Vessel 20 and from the system (step 51). Supernatant is also removed as treated water 72, and undergoes further processing at the Treated Water Processing Unit 73 before being expelled from the system as Purified Water 74 (step 52). The sterilization can be performed as described in U.S. Pat. No. 10,287,194, issued May 14, 2019, to Ohki et al., the disclosure of which is incorporated by reference, though other ways to perform the sterilization are possible.

(47) Optionally, the amount of the sludge 21 that is collected in the Sludge Storage Vessel can be measured (such as by weighing the sludge 21), with the results of the measurement being used to adjust the ratio of gas-dispersion return sludge 36 to wastewater 11 used to form the mixed liquor 17 in subsequent repetitions of the method 40 (step 53). For example, if more than a desired amount of sludge 21 was measured, the ratio of the amount of the gas-dispersion return sludge 36 to the amount of the wastewater 11 used to form the mixed liquor 17 can be increased in subsequent runs of the method 40 (thus reducing the overall amount of digestible pollutants available to the microorganisms and increasing the probability that all of the degradable pollutants will be digested by the microorganisms via the digestive function). Alternatively, if not enough sludge 21 was created, the ratio of the amount of the gas-dispersion return sludge 36 to the amount of the wastewater 11 used to form the mixed liquor 17 can be decreased in subsequent runs of the method 40 (thus increasing the amount of the degradable pollutants available to the microorganisms, which, can be used for reproduction of the microorganism following the satiation of the digestive function).

(48) If more wastewater 11 to be treated remains (step 54), whether the amount of solid pollutants, organic and inorganic, in the next batch of wastewater 11 to be treated requires action via execution of steps 44 and 45 is determined (step 55). The determination can be made by comparing the level of the solids to one or more thresholds, though other kinds of determinations are possible. If the level requires action (step 55), the method returns to step 44. If the level does not require action (55), the method 40 returns to step 46. If no more wastewater 11 remains to be processed (step 52), the method 40 ends.

(49) Providing the gas-dispersion return sludge 36 solely into the one or more Aerobic Reaction Vessels 16, possibly via the Mixer/Distributor 15, allows to achieve an optimum quantity of the aerobic microorganisms within the Aerobic Reaction Vessels 16. FIG. 3 is a flow diagram showing a routine for forming gas-dispersion return sludge and returning the gas-dispersion return sludge 36 to the one or more aerobic reaction vessels 16 for use in the method of FIG. 2A-2B in accordance with one embodiment.

(50) Reactive gas, pure oxygen or oxygen containing trace amounts of ozone, is generated by the Oxygen and Ozone Generator 28 (step 61). As described above, either the Atomizer 24 or the Pump 22 is installed along the Return Sludge Pipeway 26. Once the reactive gas is introduced into the return sludge 35, either within the Return Sludge Pipeway 26 or through the valves 136 into the Pump 22 (or the Atomizer 24), the return sludge 35 is converted into a gas-liquid mixed liquor (step 62). When this gas-liquid mixed liquor (sludge) passes through the Atomizer 24 or the Pump 22, the reactive gas within the gas-liquid mixed liquor (sludge) is instantaneously rendered into ultra-fine bubbles (bubble diameter less than 30 ?m, ideally bubble diameter less than 1 ?m) and a portion of dissolved within the determined time (such as 2 seconds-4 seconds) (step 63). With this, a super-saturated DO value of 10-50 mg/l is realized (0.01-0.5 mg/L of ozone if ozone is also generated), and the remaining gas is dispersed, immobilized and stored within the sludge in an ultra-fine bubble state, providing a way to replenish the supply of the dissolved reactive gases and continue the digestion of the degradable pollutants.

(51) This gas-dispersion return sludge 36 containing reactive gas is supplied by the Atomizer 24 or the Pump 22 only to the one or more Aerobic Reaction Vessels 16 (possibly via the Mixer/Distributor 15), where the gas-dispersion return sludge 36 is formed, along with the wastewater 11, part of the mixed liquor 17 (step 64), ending the routine 60.

(52) As mentioned above, upon addition of the gas-dispersion return sludge to one or more of the Aerobic Reaction Vessels 16 any bubbling in the Aerobic Reaction Vessel 16 can be ceased. Or, in cases where the bubbling is required to prevent the settling of sludge, bubbling aeration can be minimal and may be conducted intermittently and for short periods of time.

(53) While the invention has been particularly shown and described as referenced to the embodiments thereof, those skilled in the art will understand that the foregoing and other changes in form and detail may be made therein without departing from the spirit and scope of the invention.