Integrated treatment method for liquid, gas and microbial aerosol of phosphorus-containing wastewater

Abstract

This invention relates to the field of water treatment technology, and more particularly to an integrated treatment method for liquid, gas, and microbial aerosols of phosphorus-containing wastewater. The method includes: anaerobic treatment of phosphorus-containing wastewater in an anaerobic tank to obtain intermediate treated wastewater and a first waste gas; aerobic treatment of the intermediate treated wastewater in an aerobic tank to obtain purified water and a second waste gas; introduction of the first waste gas into an electroactive reaction zone; spraying a portion of the purified water as a nutrient conductive liquid into the electroactive reaction zone; treating the second waste gas using adsorption packing to obtain intermediate purified gas; separating the intermediate purified gas using a gas separation membrane module to obtain oxygen-enriched gas and other gases; and introducing the oxygen-enriched gas into the aeration port of the aerobic tank as supplementary aeration. This treatment method, while biologically removing phosphorus from phosphorus-containing wastewater, can also treat the accompanying phosphine gas and bioaerosols, helping to eliminate safety hazards and protect the atmospheric environment.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, and in particular to an integrated treatment method for liquid, gas and microbial aerosols of phosphorus-containing wastewater. Background Technology

[0002] Eutrophication not only leads to the growth of algae in aquatic bodies but also causes a sharp decline in oxygen levels, impacting the survival of aquatic organisms such as fish. Phosphorus is the main nutrient element causing eutrophication. Excess phosphorus in water bodies primarily originates from phosphorus-containing wastewater such as industrial wastewater and domestic sewage. In domestic sewage, phosphorus from various detergents accounts for approximately 70%. Wastewater from industries such as chemical, papermaking, rubber, dyeing and textile printing, pesticides, coking, petrochemicals, fermentation, pharmaceuticals and medical treatment, and food processing often contains organophosphorus compounds.

[0003] Currently, phosphorus removal methods for phosphorus-containing wastewater can be categorized into physicochemical phosphorus removal, biological phosphorus removal, and constructed wetland phosphorus removal. Compared to physicochemical phosphorus removal, biological phosphorus removal requires virtually no additional chemical additives, and compared to constructed wetland phosphorus removal, its equipment footprint is relatively smaller. Therefore, wastewater treatment plants typically employ biological phosphorus removal to treat phosphorus-containing wastewater. Biological phosphorus removal utilizes the biochemical action of polyphosphate-accumulating bacteria (PABs). The principle is that PABs can fully release polyphosphates within their cells under anaerobic conditions, and under aerobic conditions, they can absorb phosphorus from the water beyond their physiological needs, converting it into polyphosphates within their cells, forming phosphorus-rich biological sludge. This phosphorus-rich sludge is then discharged from the system through sedimentation, achieving the effect of phosphorus removal from the wastewater. In recent years, with the increasing environmental and health awareness of the public, how to further optimize the environmental performance of biological phosphorus removal methods and reduce safety hazards has received increasing attention from those skilled in the art. Summary of the Invention

[0004] To solve or partially solve the problems existing in related technologies, the present invention provides an integrated treatment method for liquid, gas and microbial aerosol of phosphorus-containing wastewater.

[0005] This invention provides an integrated treatment method for liquid, gas, and microbial aerosols of phosphorus-containing wastewater, characterized by comprising the following steps:

[0006] Step a) The phosphorus-containing wastewater is fed into an anaerobic tank for anaerobic treatment to obtain intermediate treated wastewater and first waste gas, the first waste gas containing phosphine.

[0007] Step b) The intermediate wastewater is introduced into an aerobic tank for aerobic treatment to obtain purified water and a second waste gas, the second waste gas containing microbial aerosols;

[0008] Step c) The first waste gas is introduced into the electroactive reaction zone, and the first waste gas is treated by electroactive microorganisms to obtain purified gas; the electroactive reaction zone includes: a porous packing material in which electroactive microorganisms are cultivated, and an electrode in contact with the porous packing material;

[0009] A portion of the purified water is exported as a nutrient conductive liquid and sprayed onto the electroactive reaction zone.

[0010] The waste liquid and excess nutrient conductive liquid generated during treatment are introduced into the aerobic tank, and step b) is repeated.

[0011] Step d) The second waste gas is treated using adsorption packing material to obtain intermediate purified gas;

[0012] Step e) Use a gas separation membrane module to separate the intermediate purified gas to obtain oxygen-enriched gas and other gases; introduce the oxygen-enriched gas into the aeration port of the aerobic tank as supplementary aeration.

[0013] Furthermore, the anaerobic tank is an upflow anaerobic tank; step a) specifically includes:

[0014] Phosphorus-containing wastewater is introduced into the anaerobic tank through the inlet and discharged from the outlet of the anaerobic tank along the flow direction of the first horizontal baffle plate inside the anaerobic tank, resulting in intermediate treated wastewater; the first waste gas generated is discharged from the exhaust port at the top of the anaerobic tank.

[0015] Further, step c) specifically includes:

[0016] The first waste gas is introduced from the bottom of the electrobiological phosphorus oxidation tank located above the anaerobic tank, and after being evenly distributed by the air guide plate, it comes into contact with the electroactive reaction zone in the electrobiological phosphorus oxidation tank. The electroactive reaction zone includes: a porous packing material in which electroactive microorganisms are cultivated, and an electrode in contact with the porous packing material.

[0017] A portion of the purified water is exported as a nutrient conductive liquid and sprayed from the upper spray mechanism of the electrobiological phosphorus oxidation tank onto the electroactive reaction zone.

[0018] The waste liquid and excess nutrient conductive liquid generated during treatment are discharged from the outlet of the electrobiological phosphorus oxidation tank and introduced into the aerobic tank, and step b is repeated.

[0019] Furthermore, the porous filler is polyurethane.

[0020] Furthermore, the electroactive microorganism is one or both of Pseudomonas aeruginosa and Bacillus.

[0021] Furthermore, the aerobic tank is an upflow aerobic tank; step b) specifically includes:

[0022] The intermediate-treatment wastewater is introduced into the aerobic tank through the inlet, guided by the second horizontal baffle plate in the aerobic tank, and then enters the membrane module in the aerobic tank. It is discharged from the outlet of the membrane module to obtain purified water. The generated second waste gas is discharged from the exhaust port at the top of the aerobic tank. The second waste gas contains microbial aerosols.

[0023] Further, step d) specifically includes:

[0024] The second waste gas is introduced from the bottom of the baffle adsorption tank located above the aerobic tank, and travels along the flow direction of the vertical baffles in the baffle adsorption tank. During its travel, it comes into contact with the adsorption packing material in the baffle adsorption tank, and the resulting intermediate purified gas is discharged from the exhaust port at the top of the baffle adsorption tank.

[0025] Further, step e) specifically includes:

[0026] The intermediate purified gas is separated from the gas membrane separation tank located above the baffled adsorption tank by the gas separation membrane module inside the gas membrane separation tank to obtain oxygen-enriched gas and other gases; the oxygen-enriched gas is introduced into the aeration port of the aerobic tank as supplementary aeration.

[0027] Furthermore, the adsorption filler is activated carbon, ceramsite, diatomaceous earth, quartz sand, or molecular sieve.

[0028] Furthermore, the hydraulic retention time of the anaerobic and aerobic tanks is 5–12 hours.

[0029] The integrated treatment method for liquid, gas, and microbial aerosols of phosphorus-containing wastewater provided by this invention can include the following beneficial effects:

[0030] 1. This treatment method first employs biological phosphorus removal for wastewater treatment, and then uses electroactive microorganisms and adsorption packing materials to treat the phosphine generated during anaerobic treatment and the microbial aerosol generated during aerobic treatment, respectively. Therefore, this treatment method can simultaneously remove phosphorus from phosphorus-containing wastewater biologically and treat the accompanying phosphine gas and bioaerosols, helping to eliminate safety hazards and protect the atmospheric environment.

[0031] 2. In this treatment method, a portion of the purified water discharged from the aerobic tank is returned to the electroactive reaction zone as a nutrient solution and conductive liquid for electroactive microorganisms. Simultaneously, the gas treated by the adsorption packing material is further separated by a gas membrane separation component, and the oxygen-enriched air is returned to the aerobic tank as supplementary aeration, saving energy. Therefore, this treatment system also achieves the reuse of oxygen and phosphorus resources.

[0032] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0033] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same parts.

[0034] Figure 1 This is a schematic diagram illustrating the steps of an integrated treatment method for phosphorus-containing wastewater using liquid, gas, and microbial aerosols, as shown in an embodiment of the present invention.

[0035] Figure 2 This is a schematic flowchart of the integrated treatment method for liquid, gas and microbial aerosol of phosphorus-containing wastewater provided in the embodiments of the present invention.

[0036] Figure 3 This is a schematic diagram of the equipment structure for implementing the integrated treatment method of liquid, gas and microbial aerosol for phosphorus-containing wastewater according to embodiments of the present invention.

[0037] Explanation of reference numerals in the attached figures

[0038] 1-Anaerobic tank

[0039] 2-Aerobic tank

[0040] 3-Electroactive reaction zone

[0041] 31-Porous packing

[0042] 32-electrode

[0043] 3'-Electrobiological phosphorus oxidation pond

[0044] 4-Adsorption packing

[0045] 4'-Baffled Adsorption Tank

[0046] 5-Gas Membrane Separation Component

[0047] 5'-Gas Membrane Separator

[0048] In the anaerobic tank:

[0049] 11-Inlet

[0050] 12-Outlet

[0051] 13-Exhaust Port

[0052] 14-First horizontal baffle

[0053] In the aerobic tank:

[0054] 21-Inlet

[0055] 22-Outlet

[0056] 23-Second Horizontal Baffle

[0057] 24-Aeration port

[0058] 25-Membrane Module

[0059] 26-Exhaust port

[0060] In the electrobiological phosphorus oxidation pond:

[0061] 33-Air guide plate

[0062] 34-Spraying Mechanism

[0063] 35-Outlet

[0064] 36-Exhaust Port

[0065] In a baffled adsorption tank:

[0066] 41-Vertical deflector

[0067] 42-Exhaust Port Detailed Implementation

[0068] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0069] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular forms “a,” “the,” and “the” used in this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0070] It should be understood that although the terms "first," "second," "third," etc., may be used in this invention to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this invention, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0071] The inventors of this application have discovered through research that while biological phosphorus removal is effective in treating phosphorus in wastewater, microorganisms, unlike chemical agents, possess life and metabolic characteristics, thus generating other pollutants, primarily phosphine gas and bioaerosols. These two types of pollutants, if directly released into the atmosphere, will pollute the surrounding environment and harm human health. Specifically:

[0072] Studies have found that obligate anaerobic bacteria, such as phosphate-reducing bacteria, can reduce organic phosphorus compounds and inorganic phosphates in an anaerobic environment to phosphine. Phosphine is a gaseous, colorless, and highly toxic inorganic compound. Pure phosphine gas is colorless and odorless, but when metal phosphides produce phosphine gas, it often has an acetylene, garlic, or rotten fish odor. Inhalation of phosphine can affect the heart, respiratory system, kidneys, gastrointestinal tract, nervous system, and liver. Phosphine gas released into the air pollutes the surrounding environment and harms human health.

[0073] Biological phosphorus removal wastewater treatment systems contain a large number of microorganisms. Disturbed by aeration or mechanical agitation, some smaller microorganisms in the wastewater or sludge escape into the surrounding air, forming bioaerosols. Additionally, bioreactors treating waste gas contain a large number of microorganisms. Due to the impact of the incoming airflow, microorganisms attached to the packing surface are carried out of the bioreactor, also contributing to bioaerosol emissions. Bioaerosols typically refer to aerosols with an aerodynamic diameter of less than 100 μm containing microorganisms or other bioactive substances, including bacteria, fungi, viruses, endotoxins, as well as fungal spores, fern spores, and protozoa. Besides possessing the characteristics of general aerosols, they also exhibit infectivity and sensitization. Of the approximately 500 pathogenic bacteria worldwide, more than 100 are transmitted through aerosols, posing a threat to human health. Recent studies have also found that microbial aerosols are important precursors to smog formation.

[0074] Therefore, the inventors of this application considered that while using biological phosphorus removal to treat phosphorus-containing wastewater, the co-treatment of phosphine waste gas and bioaerosols could be achieved, which is of great significance for eliminating safety hazards and protecting the atmospheric environment.

[0075] This invention provides an integrated treatment method for liquid, gas, and microbial aerosols of phosphorus-containing wastewater. Please refer to [link to relevant documentation]. Figure 1 It includes the following steps:

[0076] Step a) The phosphorus-containing wastewater is fed into an anaerobic tank for anaerobic treatment to obtain intermediate treated wastewater and first waste gas, the first waste gas containing phosphine.

[0077] Step b) The intermediate wastewater is introduced into an aerobic tank for aerobic treatment to obtain purified water and a second waste gas, the second waste gas containing microbial aerosols;

[0078] Step c) The first waste gas is introduced into the electroactive reaction zone, and the first waste gas is treated by electroactive microorganisms to obtain purified gas; the electroactive reaction zone includes: a porous packing material in which electroactive microorganisms are cultivated, and an electrode in contact with the porous packing material;

[0079] A portion of the purified water is exported as a nutrient conductive liquid and sprayed onto the electroactive reaction zone.

[0080] The waste liquid and excess nutrient conductive liquid generated during treatment are introduced into the aerobic tank, and step b) is repeated.

[0081] Step d) The second waste gas is treated using adsorption packing material to obtain intermediate purified gas;

[0082] Step e) Use a gas separation membrane module to separate the intermediate purified gas to obtain oxygen-enriched gas and other gases; introduce the oxygen-enriched gas into the aeration port of the aerobic tank as supplementary aeration.

[0083] Please see Figure 2 This diagram illustrates the integrated treatment method for phosphorus-containing wastewater, including liquid, gas, and microbial aerosols, provided in this embodiment. The diagram shows the flow paths of water, gas, and aerosols. In this treatment method, the wastewater is first treated to remove phosphorus through an anaerobic and an aerobic tank. The first waste gas containing phosphine generated during the anaerobic treatment process is purified in an electroactive reaction zone, where electroactive microorganisms treat the first waste gas. The second waste gas containing microbial aerosols generated during the aerobic process is treated by an adsorption packing material. The resulting intermediate purified gas is then separated by a gas separation membrane assembly, and the resulting oxygen-enriched gas is introduced into the aeration port of the aerobic tank as supplementary aeration. A portion of the purified water discharged from the aerobic tank is directed as a nutrient conductive liquid and sprayed into the electroactive reaction zone. This provides nutrients to the electroactive microorganisms while increasing conductivity, promoting their growth. The waste liquid generated after treatment in the electroactive reaction zone, along with excess nutrient conductive liquid, is introduced into the aerobic tank for further recycling according to the above method. Therefore, this integrated treatment method can simultaneously treat phosphine gas and bioaerosols generated during the biological removal of phosphorus from phosphorus-containing wastewater, helping to eliminate safety hazards and protect the atmospheric environment. Furthermore, the entire system also enables the reuse of oxygen and phosphorus resources. Those skilled in the art will understand that the gas obtained after step c) and the remaining gas obtained after step e) can be directly discharged.

[0084] Step a) above involves introducing phosphorus-containing wastewater into an anaerobic tank for anaerobic treatment. Polyphosphate-accumulating bacteria (PABs) in the anaerobic tank degrade organic matter in the wastewater using nucleoside triphosphates, releasing phosphorus accumulated within their cells. The organic matter in the wastewater provides the carbon source needed for the PPAs' respiration. Under anaerobic conditions, PPAs utilize the organic matter in the wastewater for energy metabolism. The phosphorus-containing wastewater enters the anaerobic tank and comes into contact with the activated sludge, causing rapid conversion of the organic matter. Step b) above involves introducing the intermediate-treated wastewater from the anaerobic tank into an aerobic tank for aerobic treatment. In the aerobic tank, under aerobic conditions, PPAs fully absorb excess phosphorus, and then some phosphorus is removed from the wastewater through the sludge discharge port, thus reducing the phosphorus content of the wastewater. Steps a) and b) above achieve the treatment of phosphorus-containing wastewater.

[0085] Please participate Figure 3 The figure shows a schematic diagram of the equipment structure for the integrated treatment method of liquid, gas, and microbial aerosols for phosphorus-containing wastewater according to embodiments of the present invention. To save space and simplify the structure, a partition can be installed within the microbial treatment tank to separate it into the aforementioned anaerobic tank 1 and aerobic tank 2. The hydraulic retention time of anaerobic tank 1 and aerobic tank 2 is preferably 5–12 h. The aeration rate of aerobic tank 2 is preferably 25–150 L / min.

[0086] For preferred options, please refer to [link / reference]. Figure 3 The anaerobic tank 1 is an upflow anaerobic tank 1; step a) above specifically includes:

[0087] Phosphorus-containing wastewater is introduced into anaerobic tank 1 through inlet 11 and discharged from outlet 1 along the flow direction of the first horizontal baffle 14 within anaerobic tank 1, resulting in intermediate-treated wastewater. The generated first waste gas is discharged from exhaust port at the top of anaerobic tank 1. Those skilled in the art will understand that the anaerobic tank 1 is equipped with a corresponding first horizontal baffle 14 and an exhaust port 13 at the top. Using an upflow anaerobic tank 1, wastewater enters from the bottom and overflows from the top, resulting in a much longer solids retention period and microbial retention period than the hydraulic retention period, thereby improving the decomposition rate of organic matter and the efficiency of the anaerobic zone. The first horizontal baffle 14 guides the water flow into an upflow state, further enhancing the decomposition rate of organic matter and the reaction efficiency of anaerobic tank 1. Phosphine gas generated during wastewater treatment in anaerobic tank 1 accumulates at the top of the tank and is discharged through exhaust port 13 before undergoing phosphine treatment according to step c).

[0088] Ordinary phosphine-oxidizing bacteria utilize oxygen to oxidize phosphine into phosphate. In this process, phosphine releases electrons, and oxygen accepts them. The gas discharged from anaerobic tank 1 has a low oxygen content, making it difficult for ordinary phosphine-oxidizing bacteria to decompose phosphine. If oxygen is added, the anaerobic environment of anaerobic tank 1 will be disrupted because the electroactive reaction zone 3 is connected to anaerobic tank 1. To resolve this contradiction, this embodiment uses electroactive microorganisms to treat the phosphine gas. Electroactive microorganisms (such as Pseudomonas aeruginosa and Bacillus) are cultivated in electroactive reaction zone 3. Under the stimulation of the energized electrode 32, these microorganisms accumulate on and around the electrode 32 and grow rapidly. Electroactive microorganisms have the ability to acquire electrons from outside their cells, resulting in a fast electron transfer rate and high phosphine conversion efficiency even under anaerobic conditions. To increase the content of electroactive microorganisms in the electroactive reaction zone 3, a porous packing material 31 containing cultured electroactive microorganisms and an electrode 32 are provided in the electroactive reaction zone 3. The porous packing material 31 is used to adsorb and support the electroactive microorganisms, and the electrode 32 promotes the growth of the electroactive microorganisms through an external power supply. The electroactive bacterial strains pre-inoculated in the porous packing material 31 are preferably one or two of Pseudomonas aeruginosa and Bacillus.

[0089] Furthermore, step c) above is preferably:

[0090] The first waste gas is introduced from the bottom of the electrobiological phosphorus oxidation tank 3' located above the anaerobic tank 1, and after being evenly distributed by the air guide plate 33, it comes into contact with the electroactive reaction zone 3 in the electrobiological phosphorus oxidation tank 3'. The electroactive reaction zone 3 includes: a porous packing material 31 in which electroactive microorganisms are cultivated, and an electrode 32 in contact with the porous packing material 31.

[0091] A portion of the purified water is exported as a nutrient conductive liquid and sprayed from the spray mechanism 34 at the top of the electrobiological phosphorus oxidation tank 3' onto the electroactive reaction zone 3.

[0092] The waste liquid and excess nutrient conductive liquid generated during treatment are discharged from the outlet 35 of the electrobiological phosphorus oxidation tank 3' and introduced into the aerobic tank 2, and step b is repeated.

[0093] Those skilled in the art will understand that in this scheme, the electroactive reaction zone 3 is located within the electrobiological phosphorus oxidation tank 3', supported by the air guide plate 33 within the electrobiological phosphorus oxidation tank 3', and a spray mechanism 34 is provided at the top of the electrobiological phosphorus oxidation tank 3'. In this preferred scheme, the electrobiological phosphorus oxidation tank 3' is positioned above the anaerobic tank 1, which, on the one hand, makes full use of the longitudinal space and reduces the equipment footprint, and on the other hand, utilizes the light weight of the gas to simplify the design of the air guide pipeline. The air guide holes in the air guide plate 33 serve to uniformly guide the gas, allowing the first waste gas to contact the electroactive reaction zone 3 evenly, thereby improving the oxidation efficiency of the electroactive microorganisms. Furthermore, the air guide plate 33 also supports the electroactive reaction zone 3 (mainly the porous packing 31). Further, the porous packing 31 is polyurethane, which has a large specific surface area and is lightweight, thus reducing the weight of the packing and the load-bearing capacity of the air guide plate 33 while adsorbing a large number of electroactive microorganisms. The electrode 32 is preferably a graphite electrode 32, a carbon felt electrode 32, or a carbon fiber electrode 32. Preferably, the electrode 32 is arranged in a horizontal direction, which is beneficial to increasing the contact area between the gas and the electroactive microorganisms on the electrode 32.

[0094] After being treated in the aerobic tank 2, the purified water is discharged in two parts. One part is discharged, and the other part is connected to the spray mechanism 34 and comes into contact with the electroactive reaction zone 3 through spraying. Its function is as follows: on the one hand, the phosphate and other components contained in the purified water discharged from the aerobic tank 2 can serve as nutrients required for the growth of microorganisms in the electroactive reaction zone 3, that is, as a nutrient solution for microorganisms; on the other hand, for the porous packing material 31 with poor conductivity, the conductivity of water can be used to increase the electron conduction area in the reaction zone, which is beneficial to increasing the content of electroactive microorganisms.

[0095] The first waste gas discharged from the aerobic tank 2 rises and enters the bottom of the electrobiological phosphorus oxidation tank 3', continuing to move upward. Under the diversion effect of the air guide plate 33, it enters the electroactive reaction zone 3 evenly, where it is oxidized by electroactive microorganisms, transferring from the gas phase to the liquid phase and being converted into phosphate. The gas treated in the electroactive reaction zone 3 can be discharged from the exhaust port 36 at the top of the electrobiological phosphorus oxidation tank 3'. The liquid phase is discharged from the outlet 35 of the electrobiological phosphorus oxidation tank 3' and introduced into the aerobic tank 2 for further treatment according to step b). Those skilled in the art will understand that, for the convenience of liquid phase discharge, the outlet 35 of the electrobiological phosphorus oxidation tank 3' is preferably located at the bottom.

[0096] The aforementioned aerobic tank 2 is preferably an upflow aerobic tank 2; step b) specifically includes:

[0097] The intermediate-treatment wastewater is introduced into the aerobic tank 2 through the inlet 21, guided by the second horizontal baffle 23 within the aerobic tank 2, and reaches the aeration port 24. It then enters the membrane module 25 within the aerobic tank 2 and is discharged from the outlet 22 of the membrane module 25, yielding purified water. The generated second waste gas, containing microbial aerosols, is discharged from the exhaust port at the top of the aerobic tank 2. Those skilled in the art will understand that the aerobic tank 2 is equipped with the second horizontal baffle 23 and the membrane module 25, and the top is equipped with the exhaust port 26. The second horizontal baffle 23, positioned above the inlet 21, guides the water flow and prolongs the residence time of the wastewater in the aerobic tank 2. Furthermore, by positioning the second horizontal baffle 23 below the aeration port 24, it prevents air / oxygen discharged from the aeration port 24 from entering the anaerobic tank 1, thus helping to maintain the anaerobic state within the anaerobic tank 1. Membrane module 25 is used for solid-liquid separation, intercepting polyphosphate-accumulating bacteria in aerobic tank 2 to prevent bacterial loss and control suspended solids (SS) in the effluent, thus eliminating the need for a sedimentation tank. Those skilled in the art will understand that the outlet of the membrane module 25 forms the effluent outlet of the aerobic tank 2, with the inlet located above the aeration pipe. The membrane module 25 can be a hollow fiber membrane module 25, a flat sheet membrane module 25, a spiral wound membrane module 25, a tubular membrane module 25, or a pleated filter cartridge module. The membrane material can be a polyolefin membrane, a polyethylene membrane, a polyacrylonitrile membrane, a polysulfone membrane, or an aromatic polyamide membrane. The second waste gas containing microbial aerosols generated during wastewater treatment in aerobic tank 2 is discharged from the top exhaust port 26 and then adsorbed using adsorption packing 4 according to step d).

[0098] Furthermore, step d) above specifically refers to:

[0099] The second waste gas is introduced from the bottom of the baffle adsorption tank 4' located above the aerobic tank 2, and travels along the flow direction of the vertical baffle plate 41 in the baffle adsorption tank 4'. During the travel, it comes into contact with the adsorption packing 4 in the baffle adsorption tank 4', and the resulting intermediate purified gas is discharged from the exhaust port 42 at the top of the baffle adsorption tank 4'.

[0100] In this scheme, the adsorption packing 4 is placed inside the baffled adsorption tank 4', which is positioned above the aerobic tank 2. The second waste gas generated in the aerobic tank 2 moves upward and enters the bottom of the baffled adsorption tank 4'. Those skilled in the art will understand that, in addition to the adsorption packing 4, the baffled adsorption tank 4' also contains vertical baffles, and an exhaust port is located at the top. The second waste gas containing microbial aerosols enters the baffled adsorption tank 4' from the exhaust port at the top of the aerobic tank 2. Under the guidance of the vertical baffles, it passes through the adsorption packing 4 along the guiding path. The microbial aerosols are trapped in the adsorption packing 4, and the purified intermediate gas is discharged from the exhaust port 42 at the top of the baffled adsorption tank 4'. The vertical baffles extend the residence time of the second waste gas in the baffled adsorption tank 4', allowing the microbial aerosols to fully contact the adsorption packing 4 and improving the retention effect. The aforementioned adsorption packing material 4 is preferably activated carbon, ceramsite, diatomaceous earth, quartz sand, or molecular sieve, with molecular sieve being more preferred. Molecular sieves release a large amount of heat during the adsorption of bioaerosols, thus inactivating the bacteria adsorbed on them. The analytical sieve is preferably a 4A molecular sieve or a 13X molecular sieve. The residence time of the gas in the baffled adsorption cell 4' is preferably 0.5–6 minutes.

[0101] Furthermore, step e) above specifically refers to:

[0102] The intermediate purified gas is separated from the gas membrane separation tank 5' located above the baffled adsorption tank 4' by the gas separation membrane assembly 25 in the gas membrane separation tank 5' to obtain oxygen-enriched gas and other gases; the oxygen-enriched gas is introduced into the aeration port 24 of the aerobic tank 2 as supplementary aeration.

[0103] In this scheme, the gas separation membrane module 25 is placed inside the gas membrane separation tank 5', which is positioned above the baffled adsorption tank 4'. The intermediate purified gas discharged from the baffled adsorption tank 4' moves upward and enters the gas membrane separation tank 5'. The gas flows through the gas separation membrane module 25 to achieve multi-component gas separation. Gas membrane separation technology is based on pressure and utilizes the differences in the adsorption capacity of each component in the gas on the surface of the polymer membrane and the differences in dissolution-diffusion within the membrane, i.e., the permeation rate difference, to achieve separation. Generally, all gases can permeate the polymer membrane. The process involves gas molecules first being adsorbed and dissolved on the high-pressure side surface of the membrane, then diffusing within the membrane due to the concentration gradient, and finally desorbing from the low-pressure side. The structure is such that small molecules and highly polar molecules pass through faster, while large molecules and less polar molecules pass through slower. Membrane separation oxygen generation technology uses air as a raw material. Under certain pressure conditions, air is passed through a membrane, and oxygen and nitrogen are separated by utilizing the different permeation rates of gases with different properties, such as oxygen and nitrogen. The driving force for separation is the partial pressure difference of the gases on both sides of the membrane. Therefore, membrane gas separation does not involve phase change and does not require regeneration. Oxygen in the air permeates quickly, preferentially passing through the membrane and becoming enriched. Other gases permeate more slowly and remain largely on the raw air side, forming permeate gas. Driven by the pressure difference across the membrane, oxygen continuously permeates through the semi-permeable membrane to form oxygen-enriched air. The separated oxygen-enriched gas is introduced into the aeration port 24 of the aerobic tank 2 as supplementary aeration, while the remaining gases can be directly discharged. The gas separation membrane module 25 can specifically be a flat-sheet membrane module 25, a spiral wound membrane module 25, or a hollow fiber membrane module 25. The membrane material of the gas separation membrane module 25 can be polysulfone, silicone rubber, or polyphenylene ether.

[0104] As can be seen from the above, the integrated treatment method for liquid, gas, and microbial aerosol of phosphorus-containing wastewater provided in this embodiment of the invention has the following advantages:

[0105] 1. This treatment method first employs biological phosphorus removal for wastewater treatment, and then uses electroactive microorganisms and adsorption packing material 4 to treat the phosphine generated during anaerobic treatment and the microbial aerosol generated during aerobic treatment, respectively. Therefore, this treatment method can not only biologically remove phosphorus from phosphorus-containing wastewater, but also treat the accompanying phosphine gas and bioaerosols, which helps to eliminate safety hazards and protect the atmospheric environment.

[0106] 2. In this treatment method, a portion of the purified water discharged from the aerobic tank 2 is returned to the electroactive reaction zone 3 as a nutrient solution and conductive liquid for electroactive microorganisms. Simultaneously, the gas treated by the adsorption packing 4 is further separated by the gas membrane separation component 5, and the oxygen-enriched air is returned to the aerobic tank 2 as supplementary aeration, saving energy. Therefore, this treatment system also achieves the reuse of oxygen and phosphorus resources.

[0107] The technical solution of the present invention will be further described below with reference to specific embodiments:

[0108] The following embodiments all adopt the following... Figure 3 The equipment shown treats phosphorus-containing wastewater in the following manner:

[0109] 1. Phosphorus-containing wastewater is introduced into the anaerobic tank 1 through the inlet 11 and discharged from the outlet 12 of the anaerobic tank 1 along the flow direction of the first horizontal baffle 14 in the anaerobic tank 1, resulting in intermediate treated wastewater; the first waste gas generated is discharged from the exhaust port 13 at the top of the anaerobic tank 1 and enters the bottom of the electrobiological phosphorus oxidation tank 3'.

[0110] 2. The intermediate treated wastewater is introduced into the aerobic tank 2 through the inlet 21, and after being guided by the second horizontal baffle 23 in the aerobic tank 2, it reaches the aeration port 24. Then it enters the membrane module 25 in the aerobic tank 2 and is discharged from the outlet 22 of the membrane module 25 to obtain purified water. The generated second waste gas containing microbial aerosol is discharged from the exhaust port at the top of the aerobic tank 2 and enters the bottom of the baffle adsorption tank 4'.

[0111] 3. The first waste gas enters the bottom of the electrobiological phosphorus oxidation tank 3' and is evenly distributed by the air guide plate 33 before contacting the electroactive reaction zone 3. The electroactive reaction zone 3 includes: a porous packing material 31 in which Pseudomonas aeruginosa and Bacillus are cultivated, and an electrode 32 in contact with the porous packing material 31; the treated gas is discharged from the exhaust port 36.

[0112] A portion of the purified water is exported as a nutrient conductive liquid and sprayed from the spray mechanism 34 at the top of the electrobiological phosphorus oxidation tank 3' onto the electroactive reaction zone 3.

[0113] The waste liquid and excess nutrient conductive liquid generated during treatment are discharged from the outlet 35 of the electrobiological phosphorus oxidation tank 3' and introduced into the aerobic tank 2, and step 2 is repeated.

[0114] 4. The second waste gas enters the bottom of the baffle adsorption tank 4' and travels along the flow direction of the vertical baffle plate 41. During the travel, it comes into contact with the adsorption packing 4 inside the baffle adsorption tank 4'. The resulting intermediate purified gas is discharged from the exhaust port 42 at the top of the baffle adsorption tank 4' and enters the bottom of the gas membrane separation tank 5'.

[0115] 5. The intermediate purified gas enters the gas membrane separation tank 5' and is separated by the gas separation membrane module 25 to obtain oxygen-enriched gas and other gases; the oxygen-enriched gas is introduced into the aeration port of the aerobic tank 2 as supplementary aeration.

[0116] Example 1

[0117] Anaerobic tank:

[0118] Dimensions: Length, width, and height are 0.3m, 0.6m, and 0.5m respectively.

[0119] Hydraulic residence time: 10h

[0120] Aerobic tank:

[0121] Dimensions: Length, width, and height are 0.9m, 0.6m, and 0.5m respectively.

[0122] Hydraulic residence time: 10h

[0123] Aeration rate: 30L / min

[0124] Membrane module:

[0125] Hollow fiber membrane module; the membrane material is polyethylene membrane.

[0126] Electrobiological phosphorus oxidation pond:

[0127] Dimensions: Length, width, and height are 0.4m, 0.6m, and 0.3m respectively.

[0128] The porous filler is lightweight and porous polyurethane, and the anode and cathode electrode materials are carbon fiber.

[0129] Baffled adsorption tank:

[0130] Dimensions: Length, width, and height are 0.7m, 0.6m, and 0.15m respectively.

[0131] Adsorption packing material: 4A molecular sieve

[0132] Gas residence time: 2 min

[0133] Gas membrane separator:

[0134] Dimensions: Length, width, and height are 0.7m, 0.6m, and 0.15m respectively.

[0135] Gas separation membrane module: spiral wound membrane module, 3 sets in total; membrane material is polysulfone.

[0136] Membrane area: 0.15m² 2

[0137] The treatment results of phosphorus-containing wastewater are as follows:

[0138] The initial concentrations of phosphorus, phosphine, and bacterial aerosols were 10.5 mg / L, 1.29 mg / m³, and 1.29 mg / m³, respectively. 3 642 CFU / m 3 After treatment, the concentrations were 0.30 mg / L and 0.03 mg / m³, respectively. 3 0 CFU / m 3The removal rates reached 97.1%, 97.7%, and 100.0%, respectively. The concentration of total phosphorus emitted was lower than the national standards for pollutant discharge from urban wastewater treatment plants, and the concentration of bioaerosol emissions was lower than the national standards for indoor air quality.

[0139] Example 2

[0140] Anaerobic tank:

[0141] Dimensions: Length, width, and height are 1.5m, 3m, and 1.6m respectively.

[0142] Hydraulic residence time: 6 hours

[0143] Aerobic tank:

[0144] Dimensions: Length, width, and height are 4.5m, 3m, and 1.6m respectively.

[0145] Hydraulic residence time: 6 hours

[0146] Aeration rate: 140L / min

[0147] Membrane module:

[0148] Tubular membrane module; membrane material is polyethylene membrane.

[0149] Electrobiological phosphorus oxidation pond:

[0150] Dimensions: Length, width, and height are 3m, 3m, and 0.75m respectively.

[0151] The porous filler is granular activated carbon, and the anode and cathode electrode materials are carbon felt;

[0152] Baffled adsorption tank:

[0153] Dimensions: Length, width, and height are 3m, 3m, and 0.8m respectively.

[0154] Adsorption packing material: 4A molecular sieve

[0155] Gas residence time: 5 min

[0156] Gas membrane separator:

[0157] Dimensions: Length, width, and height are 3m, 3m, and 0.8m respectively.

[0158] Gas separation membrane module:

[0159] Spiral wound membrane module, the membrane material is silicone rubber.

[0160] Dimensions: Length, width, and height are 3m, 3m, and 0.8m respectively.

[0161] Membrane area: 3.5m² 2

[0162] The treatment results of phosphorus-containing wastewater are as follows:

[0163] The initial concentrations of phosphorus, phosphine, and bacterial aerosols were 18.6 mg / L, 1.05 mg / m³, and 1.05 mg / m³, respectively. 3 1001 CFU / m 3 After treatment, the concentrations were 0.29 mg / L and 0.03 mg / m³, respectively. 3 75 CFU / m 3 The removal rates reached 98.4%, 97.1%, and 92.5%, respectively. The concentration of total phosphorus emitted was lower than the national standards for pollutant discharge from urban wastewater treatment plants, and the concentration of bioaerosol emissions was lower than the national standards for indoor air quality.

[0164] Example 3

[0165] Anaerobic tank:

[0166] Dimensions: Length, width, and height are 0.25m, 0.5m, and 0.6m respectively.

[0167] Hydraulic residence time: 8h

[0168] Aerobic tank:

[0169] Dimensions: Length, width, and height are 0.75m, 0.5m, and 0.6m respectively.

[0170] Hydraulic residence time: 8h

[0171] Aeration rate: 90L / min

[0172] Membrane module:

[0173] Flat sheet membrane module; the membrane material is polysulfone membrane.

[0174] Electrobiological phosphorus oxidation pond:

[0175] Dimensions: Length, width, and height are 0.4m, 0.5m, and 0.4m respectively.

[0176] The porous filler is lightweight and porous polyurethane, and the anode and cathode electrode materials are carbon rods;

[0177] Baffled adsorption tank:

[0178] Dimensions: Length, width, and height are 0.6m, 0.5m, and 0.3m respectively.

[0179] Adsorption packing material: 13X molecular sieve

[0180] Gas residence time: 1 min

[0181] Gas membrane separator:

[0182] Dimensions: Length, width, and height are 0.6m, 0.5m, and 0.1m respectively.

[0183] Gas separation membrane module:

[0184] Flat-panel membrane module; membrane material is polysulfone.

[0185] Membrane area: 0.2m² 2

[0186] The treatment results of phosphorus-containing wastewater are as follows:

[0187] The initial concentrations of phosphorus, phosphine, bacterial aerosols, and fungal aerosols were 17.1 mg / L, 2.04 mg / m³, and 17.1 mg / L, 2.04 mg / m³, respectively. 3 530 CFU / m 3 284 CFU / m 3 After treatment, the concentrations were 0.9 mg / L and 0.04 mg / m³, respectively. 3 4 CFU / m 3 6 CFU / m 3 The removal rates reached 94.7%, 98.0%, 99.2%, and 97.9%, respectively. The concentration of total phosphorus emitted was lower than the national standards for pollutant discharge from urban wastewater treatment plants, and the concentration of bioaerosol emissions was lower than the national standards for indoor air quality.

[0188] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An integrated treatment method for liquid, gas, and microbial aerosols of phosphorus-containing wastewater, characterized in that, Includes the following steps: Step a) The phosphorus-containing wastewater is fed into an anaerobic tank for anaerobic treatment to obtain intermediate treated wastewater and first waste gas, the first waste gas containing phosphine. Step b) The intermediate wastewater is introduced into an aerobic tank for aerobic treatment to obtain purified water and a second waste gas, the second waste gas containing microbial aerosols; Step c) The first waste gas is introduced into the electroactive reaction zone, and the first waste gas is treated by electroactive microorganisms to obtain purified gas; the electroactive reaction zone includes: a porous packing material in which electroactive microorganisms are cultivated, and an electrode in contact with the porous packing material; A portion of the purified water is exported as a nutrient conductive liquid and sprayed onto the electroactive reaction zone. The waste liquid and excess nutrient conductive liquid generated during treatment are introduced into the aerobic tank, and step b) is repeated. Step d) The second waste gas is treated using adsorption packing material to obtain intermediate purified gas; Step e) Use a gas separation membrane module to separate the intermediate purified gas to obtain oxygen-enriched gas and other gases; introduce the oxygen-enriched gas into the aeration port of the aerobic tank as supplementary aeration.

2. The processing method according to claim 1, characterized in that, The anaerobic tank is an upflow anaerobic tank; step a) specifically involves: Phosphorus-containing wastewater is introduced into the anaerobic tank through the inlet and discharged from the outlet of the anaerobic tank along the flow direction of the first horizontal baffle plate inside the anaerobic tank, resulting in intermediate treated wastewater; the first waste gas generated is discharged from the exhaust port at the top of the anaerobic tank.

3. The processing method according to claim 1, characterized in that, Step c) specifically involves: The first waste gas is introduced from the bottom of the electrobiological phosphorus oxidation tank located above the anaerobic tank, and after being evenly distributed by the air guide plate, it comes into contact with the electroactive reaction zone in the electrobiological phosphorus oxidation tank. The electroactive reaction zone includes: a porous packing material in which electroactive microorganisms are cultivated, and an electrode in contact with the porous packing material. A portion of the purified water is exported as a nutrient conductive liquid and sprayed from the upper spray mechanism of the electrobiological phosphorus oxidation tank onto the electroactive reaction zone. The waste liquid and excess nutrient conductive liquid generated during treatment are discharged from the outlet of the electrobiological phosphorus oxidation tank and introduced into the aerobic tank, and step b is repeated.

4. The processing method according to claim 3, characterized in that, The porous filler is polyurethane.

5. The processing method according to claim 1, characterized in that, The electroactive microorganisms are one or two of Pseudomonas aeruginosa and Bacillus.

6. The processing method according to claim 1, characterized in that, The aerobic tank is an upflow aerobic tank; step b) specifically involves: The intermediate treated wastewater is introduced into the aerobic tank through the inlet, guided by the second horizontal baffle plate in the aerobic tank, and then enters the membrane module in the aerobic tank. It is discharged from the outlet of the membrane module to obtain purified water. The generated second waste gas is discharged from the exhaust port at the top of the aerobic tank. The second waste gas contains microbial aerosols.

7. The processing method according to claim 6, characterized in that, Step d) specifically refers to: The second waste gas is introduced from the bottom of the baffle adsorption tank located above the aerobic tank, and travels along the flow direction of the vertical baffles in the baffle adsorption tank. During its travel, it comes into contact with the adsorption packing material in the baffle adsorption tank, and the resulting intermediate purified gas is discharged from the exhaust port at the top of the baffle adsorption tank.

8. The processing method according to claim 7, characterized in that, Step e) specifically involves: The intermediate purified gas is separated from the gas membrane separation tank located above the baffled adsorption tank by the gas separation membrane module inside the gas membrane separation tank to obtain oxygen-enriched gas and other gases; the oxygen-enriched gas is introduced into the aeration port of the aerobic tank as supplementary aeration.

9. The processing method according to claim 1, characterized in that, The adsorption filler material is activated carbon, ceramsite, diatomaceous earth, quartz sand, or molecular sieve.

10. The processing method according to claim 1, characterized in that, The hydraulic retention time of the anaerobic and aerobic tanks is 5–12 hours.

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