Water-gas integrated treatment system and method for enhancing absorption and coupling biological treatment

Abstract

The invention belongs to the technical field of air pollution control, and particularly relates to a water-gas integrated treatment system and method for enhancing absorption and coupling biological treatment. The system comprises a primary enhanced absorption unit, a secondary absorption and biological coupling unit and a control unit. To-be-treated malodorous waste gas sequentially enters the first-stage enhanced absorption unit and the second-stage absorption and biological coupling unit, is primarily purified in the first-stage enhanced absorption unit under the action of the composite absorbent, and then is deeply purified in the second-stage absorption and biological coupling unit under the coupling action of the composite absorbent and the microbial agent. The system solves the problems that a biological method is poor in hydrophobic waste gas effect and an absorption method is easy to saturate and lose efficacy; meanwhile, wastewater purification is realized, the problem of secondary pollution of wastewater is solved, and integrated treatment of water is realized. The method is compact in structure, environmentally friendly, low in cost, wide in application range, good in treatment effect and high in load fluctuation resistance.

Description

Technical Field

[0001] This invention belongs to the field of air pollution control technology, specifically relating to an integrated water and air treatment system and method with enhanced absorption coupled with biological treatment. Background Technology

[0002] Odor pollutants include ammonia, hydrogen sulfide, methanethiol, and styrene, originating from industrial and agricultural production, domestic waste disposal, and urban public facilities. Sources of odor pollutants include municipal odor sources such as sewage and waste treatment plants, as well as industrial odor sources. Industrial odor sources are diverse; for example, the exhaust gases from industries such as feed, electronics, leather, metal surface treatment, plastics, papermaking, and textile printing and dyeing, although having low organic matter content, often have a strong odor. Furthermore, these exhaust gases often contain sticky dust, inorganic and organic matter, making their composition complex and extremely difficult to treat.

[0003] Methods for treating odorous waste gas can be divided into dry and wet methods. Dry methods, including adsorption and catalysis, are highly efficient but often have high investment and operating costs, and the presence of sticky dust in the waste gas can easily cause blockages. Wet methods include absorption and biological treatment. Absorption is widely applicable and particularly suitable for treating odorous and complex low-concentration organic waste gas, but traditional water spraying is inefficient, and improving absorption efficiency remains a challenge. Biological methods are more suitable for treating municipal odor sources, but they suffer from poor resistance to load fluctuations, low mass transfer efficiency for hydrophobic VOCs (such as benzene compounds and alkanes), and slow biodegradation rates.

[0004] Chinese patent CN211963501U discloses an odor gas purification device, which includes an absorption and biological treatment unit. However, the absorption and biological treatment are independent of each other, and there are still problems such as low efficiency of the absorption process, difficulty in treating the absorbed wastewater, and low degradation efficiency of the biological treatment for hydrophobic VOCs.

[0005] Chinese patent CN223209278U discloses an integrated multi-stage anti-clogging biological deodorization and purification device. The device first removes dust and humidifies, and then performs biological treatment. The device is suitable for treating waste gas with good biodegradability, but it is still difficult to effectively treat hydrophobic VOCs (such as benzene, toluene, dichloromethane, etc.) in malodorous waste gas. Summary of the Invention

[0006] To address the problems of low efficiency and secondary pollution of wastewater caused by absorption methods in existing technologies, as well as the poor resistance to load fluctuations and low degradation efficiency of hydrophobic VOCs by biological methods, the primary objective of this invention is to provide an integrated water and air treatment system that enhances absorption coupled with biological treatment.

[0007] Another objective of this invention is to provide an integrated water and air treatment method that enhances absorption coupled with biological treatment.

[0008] The objective of this invention is achieved through the following technical solution:

[0009] An integrated water and air treatment system with enhanced absorption coupled with biological treatment includes a primary enhanced absorption unit, a secondary absorption + biological coupling unit, and a control unit.

[0010] The primary enhanced absorption unit includes a primary circulating pump, a primary atomizing nozzle, a primary water storage tank, a primary dosing device, a primary pH meter, a temperature and humidity sensor, a primary packed bed, an air inlet, a water storage tank connecting pipe, and a one-way valve; wherein the primary dosing device and the primary pH meter are connected to the primary water storage tank, the inlet of the primary circulating pump is connected to the primary water storage tank, the outlet of the primary circulating pump is connected to the primary atomizing nozzle, the primary atomizing nozzle is located above the primary packed bed, and the temperature and humidity sensor is located on the air inlet pipe;

[0011] The secondary absorption + bio-coupling unit includes a secondary circulation pump, a secondary atomizing nozzle, a secondary water storage tank, a secondary dosing device, a secondary pH meter, a secondary packed bed, an aeration device, a liquid redistributor, and an aeration outlet. The secondary dosing device and the secondary pH meter are connected to the secondary water storage tank; the inlet of the secondary circulation pump is connected to the secondary water storage tank; the outlet of the secondary circulation pump is connected to the secondary atomizing nozzle; the secondary atomizing nozzle is positioned above the secondary packed bed; the aeration device is located at the bottom of the secondary absorption + bio-coupling unit; and the liquid redistributor is located at the top of the secondary packed bed.

[0012] The bottom of the primary enhanced absorption unit is connected to the bottom of the secondary absorption + biological coupling unit, allowing waste gas to pass through;

[0013] The primary water storage tank and the secondary water storage tank are connected by a water storage tank connecting pipe;

[0014] The control unit includes an air inlet detector, an air outlet detector, and a control system.

[0015] As a preferred embodiment, the packing material used in the primary packed bed is an absorbent packing material, specifically one or more of ceramic, stainless steel, or plastic packing materials.

[0016] As a preferred embodiment, the packing material used in the secondary packed bed is a combination of absorbent packing material, ceramsite and / or volcanic rock, activated carbon and / or zeolite, and bark and / or coconut shell, with the following mass ratio: 10-30% absorbent packing material, 20-40% ceramsite and / or volcanic rock, 10-30% activated carbon and / or zeolite, and 10-30% bark and / or coconut shell.

[0017] As a preferred embodiment, the secondary packing bed has four layers, with a liquid redistributor installed at the top of each packing layer to enhance the uniformity of gas-liquid distribution and avoid wall flow or channeling.

[0018] As a preferred option, microbial agents are loaded onto the packing material of the secondary packed bed.

[0019] Based on the above-mentioned treatment system, this invention also discloses an integrated water and air treatment method with enhanced absorption coupled with biological treatment, comprising: the odorous waste gas to be treated sequentially enters a primary enhanced absorption unit and a secondary absorption + biological coupling unit; firstly, it is preliminarily purified in the primary enhanced absorption unit by the action of a composite absorbent; and then, it is deeply purified in the secondary absorption + biological coupling unit by the coupling effect of the composite absorbent and microbial agents. More specific steps are as follows:

[0020] (1) The malodorous waste gas first enters the first-level enhanced absorption unit. The composite absorbent is sprayed from top to bottom through the first-level atomizing nozzle and comes into contact with the malodorous gas. Under the action of the composite absorbent, the benzene series, esters, alcohols, halogenated hydrocarbons, hydrogen sulfide, ammonia, trimethylamine and other components in the malodorous waste gas are initially removed, and a certain amount of saturated absorption tail liquid is generated at the same time.

[0021] (2) The odorous gas after preliminary purification (passing through the primary packing bed) flows to the bottom of the secondary absorption + biological coupling unit and is evenly fed into the secondary packing bed through the gas distribution device at the bottom of the secondary absorption + biological coupling unit; the odorous waste gas flows from bottom to top through the secondary packing bed to the outlet, and the odorous waste gas comes into contact with the microbial agent loaded on the packing when it passes through the secondary packing bed; at the same time, the composite absorbent sprayed from top to bottom comes into contact with the odorous waste gas in the opposite direction, and the odorous waste gas is discharged after being deeply purified under the coupling effect of the composite absorbent and the microbial agent;

[0022] In this step, the composite absorbent solubilizes the hydrophobic VOCs in the odorous waste gas, so that these components, which are difficult to biodegrade due to their poor water solubility, can be degraded by the biological agent. At the same time, the microbial agent degrades the odorous waste gas components absorbed by the composite absorbent in a timely manner, ensuring that the absorbent is in an undersaturated state and continues to play its absorption role, thereby producing a coupled and synergistic effect of absorption and biological treatment.

[0023] (3) The saturated absorption tail liquid generated in the primary enhanced absorption unit enters the secondary storage tank of the secondary absorption + biological coupling unit through the pipeline, and is sprayed onto the secondary packing bed through the secondary atomizing nozzle. The odor and organic components in the saturated absorption tail liquid are purified by the microbial agents on the packing.

[0024] The composite absorbent used in the primary enhanced absorption unit and the secondary absorption + bio-coupling unit consists of the following components by mass percentage: 0.01-2% plant extract, 0.01-2% surfactant, 1-10% cosolvent, 0.1-2% buffer, and the balance water.

[0025] Preferably, the plant extract is prepared by the following steps (A) or (B): (A) modifying the active ingredient with at least one of O2, N2, NH3 or CF4 plasma; (B) first activating the surface of the active ingredient with Ar or N2 plasma, and then reacting it in a 0.5-2.5 mol / L acrylic acid methanol solution at 20-60℃ for 0.5-5 hours.

[0026] In a more preferred embodiment, the modification treatment in step (A) takes 1-10 minutes and the discharge power is 5-500 W; the surface activation treatment in step (B) takes 1-10 minutes and the discharge power is 5-500 W. The above plasma modification or activation treatment is performed at room temperature.

[0027] The active ingredient is prepared by the method described in the invention patent application with publication number CN 114210174 A: one or more of soybean oil, palm oil, corn oil, peanut oil, olive oil, rapeseed oil, safflower seed oil, sunflower seed oil, canola seed oil, sea buckthorn seed oil, tea oil, sacha inchi oil, linseed oil, argan oil, and walnut oil are heated and dehydrated; then an acid is added and continuously stirred; then an alkaline solution is added and continuously stirred to obtain the active ingredient. This invention modifies the active ingredient by introducing functional groups containing nitrogen, oxygen, fluorine, and polar carboxyl groups as needed, thereby promoting the absorption of different components of malodorous waste gases.

[0028] More preferably, the surfactant in the composite absorbent is nonionic, specifically one or more of fatty alcohol polyoxyethylene ether, alkyl glycoside, fatty acid ethanolamide, and polysorbate; the cosolvent is one or more of ethanol, isopropanol, butanol, and ethylene glycol; and the buffer is one or more of citrate, phosphate, and acetate.

[0029] Preferably, the microbial agent is one or more of the following: sulfur-oxidizing bacteria, nitrosomonas sp., spore-forming bacteria (e.g., Bacillus subtilis), and pseudomonads that have been used in deodorization projects.

[0030] Preferably, the method further includes analyzing the concentration of odorous waste gas at the inlet and outlet in real time through the control system, and controlling the operating parameters of the dosing device, circulating pump, and atomizing nozzle to ensure that the waste gas meets the emission standards with low energy and material consumption.

[0031] In summary, the integrated water and air treatment system and method with enhanced absorption coupled with biological treatment described in this invention has the following advantages:

[0032] 1. In the secondary absorption + biological coupling unit, absorption and biodegradation have a coupled and promoting effect, which improves the purification effect of waste gas. On the one hand, the composite absorbent reduces the interfacial tension between waste gas and absorbent liquid, and increases the solubility of hydrophobic odorous waste gas in water, so that the waste gas can be degraded more fully by microorganisms, solving the problem of poor effect of biological methods on hydrophobic waste gas components. On the other hand, microorganisms degrade the absorbed waste gas components in a timely manner, keeping the absorbent liquid in an undersaturated state, which helps the continuous absorption of waste gas.

[0033] 2. The saturated wastewater generated by the primary enhanced absorption unit can directly enter the secondary absorption + biological coupling unit. The absorbent components in the saturated wastewater and the absorbed waste gas components serve as a nutrient source for microorganisms, promoting their growth. At the same time, the saturated wastewater is purified, solving the problem of secondary pollution of enhanced absorption wastewater and realizing integrated water and air treatment.

[0034] 3. This system features a compact structure and utilizes a green, environmentally friendly, and low-cost composite absorbent. The various groups of microbial agents metabolize synergistically without inhibiting each other, achieving simultaneous and efficient removal of odors and VOCs. The primary enhanced absorption unit and the secondary absorption + biological coupling unit work together to ensure stable and compliant emissions after waste gas treatment, solving the problem of poor resistance to load fluctuations in biological methods. This method has a wide range of applications and excellent treatment effects, and can be used for the treatment of odorous and low-concentration organic waste gas from sewage treatment plants, garbage stations, sewage pumping stations, pharmaceuticals, and chemical industries. Odor and VOCs concentrations can be reduced by more than 90%. Attached Figure Description

[0035] Figure 1 A schematic diagram of an integrated water and air treatment system that enhances absorption coupled with biological treatment.

[0036] In the diagram, 1 represents the primary enhanced absorption unit, 1-1 is the primary circulation pump, 1-2 is the primary atomizing nozzle, 1-3 is the primary water storage tank, 1-4 is the primary dosing device, 1-5 is the primary pH meter, 1-6 is the temperature and humidity sensor, 1-7 is the primary packed bed, 1-8 is the air inlet, 1-9 is the water storage tank connecting pipe, and 1-10 is the one-way valve. 2 represents the secondary absorption + bio-coupling unit, 2-1 is the secondary circulation pump, 2-2 is the secondary atomizing nozzle, 2-3 is the secondary water storage tank, 2-4 is the secondary dosing device, 2-5 is the secondary pH meter, 2-6 is the secondary packed bed, 2-7 is the air distribution device, 2-8 is the liquid redistributor, and 2-9 is the air outlet. 3 represents the control unit, 3-1 is the air inlet detector, 3-2 is the air outlet detector, and 3-3 is the control system. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto. All raw materials involved in the present invention can be purchased directly from the market. For process parameters not specifically specified, conventional techniques can be referred to.

[0038] like Figure 1 As shown, this invention provides an integrated water and air treatment system with enhanced absorption coupled with biological treatment, comprising a primary enhanced absorption unit 1, a secondary absorption + biological coupling unit 2, and a control unit 3:

[0039] The primary enhanced absorption unit includes a primary circulation pump 1-1, a primary atomizing nozzle 1-2, a primary water storage tank 1-3, a primary dosing device 1-4, a primary pH meter 1-5, a temperature and humidity sensor 1-6, a primary packing bed 1-7, an air inlet 1-8, a water storage tank connecting pipe 1-9, and a one-way valve 1-10. The primary water storage tank 1-3 is located at the bottom of the primary enhanced absorption unit, the air inlet 1-8 is located at the top of the primary enhanced absorption unit, the primary dosing device 1-4 and the primary pH meter 1-5 are connected to the primary water storage tank 1-3, the inlet of the primary circulation pump 1-1 is connected to the primary water storage tank 1-3, the outlet of the primary circulation pump 1-1 is connected to the primary atomizing nozzle 1-2, the primary atomizing nozzle 1-2 is located above the primary packing bed 1-7, the primary packing bed 1-7 is located above the primary water storage tank 1-3, and the temperature and humidity sensor 1-6 is located on the air inlet pipe. The primary enhanced absorption unit is used for the preliminary absorption and purification of odorous waste gas, removing some benzene compounds, esters, alcohols, halogenated hydrocarbons, hydrogen sulfide, ammonia, and trimethylamine, etc.; the primary circulation pump is connected to the primary water storage tank and the primary atomizing nozzle, used to circulate the composite absorbent from the primary water storage tank to the primary atomizing nozzle; the primary atomizing nozzle is used to atomize the composite absorbent and spray it from top to bottom to contact the odorous waste gas; the primary water storage tank is used to store the composite absorbent and spray the absorbent in at a certain circulation rate; the primary dosing device is connected to the primary water storage tank, used to replenish the absorbent as needed; the primary pH meter is connected to the primary water storage tank, used to monitor the pH value of the absorbent in real time; the temperature and humidity sensor is installed on the air inlet pipe, used to monitor the temperature and humidity of the incoming air in real time; the primary packing bed is located between the primary atomizing nozzle and the primary water storage tank, used to increase the contact area between the composite absorbent and the odorous waste gas; the air inlet is used for the odorous waste gas to enter the primary enhanced absorption unit;

[0040] The secondary absorption + bio-coupling unit includes a secondary circulation pump 2-1, a secondary atomizing nozzle 2-2, a secondary water storage tank 2-3, a secondary dosing device 2-4, a secondary pH meter 2-5, a secondary packed bed 2-6, an aeration device 2-7, a liquid redistributor 2-8, and an air outlet 2-9. The secondary water storage tank 2-3 is located at the bottom of the secondary absorption + bio-coupling unit, and the air outlet 2-9 is located at the top of the unit. The secondary dosing device 2-4, the secondary pH meter 2-5, and the secondary water storage tank 2-6 are connected to the secondary water storage tank 2-7. The water tank 2-3 is connected, the inlet of the secondary circulation pump 2-1 is connected to the secondary water storage tank 2-3, and the outlet of the secondary circulation pump 2-1 is connected to the secondary atomizing nozzle 2-2. The secondary atomizing nozzle 2-2 is set above the secondary packing bed 2-6, and the secondary packing bed 2-6 is set above the secondary water storage tank 2-3. The secondary packing bed 2-6 has four layers, and a liquid redistributor is set on the top of each packing layer. Microbial agents are loaded on the packing. The gas distribution device 2-7 is at the bottom of the secondary absorption + biological coupling unit. The secondary absorption + bio-coupling unit is used for the deep purification of waste gas after preliminary purification by the primary enhanced absorption unit. A secondary circulation pump is connected to the secondary water storage tank and the secondary atomizing nozzles to circulate the composite absorbent from the secondary water storage tank to the secondary atomizing nozzles. The secondary atomizing nozzles atomize the composite absorbent and spray it from top to bottom, ensuring full contact with the odorous waste gas in the opposite direction. A secondary dosing device is connected to the secondary water storage tank to replenish the composite absorbent as needed. A secondary pH meter is connected to the secondary water storage tank to monitor the pH value of the composite absorbent in real time. An air distribution device is located at the bottom of the secondary absorption + bio-coupling unit to evenly distribute the waste gas from the primary enhanced absorption unit into the secondary absorption + bio-coupling unit. A liquid redistributor is located at the top of each secondary packing layer to ensure that the composite absorbent sprayed from top to bottom is evenly distributed in each layer and effectively contacts and interacts with the waste gas flowing from bottom to top, preventing wall flow or channeling of the liquid in the packing section. The outlet is used to discharge the deeply purified waste gas.

[0041] The system has a gas flow chamber between the packing bed (including the primary packing bed and the secondary packing bed) and the water storage tank (including the primary water storage tank and the secondary water storage tank), which connects the primary enhanced absorption unit and the secondary absorption + biological coupling unit. The odorous gas that has been preliminarily purified by the primary enhanced absorption unit flows through the gas flow chamber to the bottom of the secondary absorption + biological coupling unit.

[0042] The water storage tank connecting pipe 1-9 connects the primary water storage tank 1-3 and the secondary water storage tank 2-3, and is used to transport the saturated absorption tail liquid in the primary water storage tank to the secondary water storage tank; the one-way valve 1-10 is installed on the water storage tank connecting pipe 1-9, and is used to control the one-way transport of the saturated absorption tail liquid in the primary water storage tank to the secondary water storage tank.

[0043] The control unit includes an air inlet detector 3-1, an air outlet detector 3-2, and a control system 3-3. The control unit is used to control operating parameters such as dosage, absorbent circulation rate, and residence time. The inlet detector is located at the inlet of the primary enhanced absorption unit to detect the initial concentration of odorous waste gas (including VOCs, odor, ammonia, trimethylamine, hydrogen sulfide, methanethiol, dimethyl sulfide, dimethyl disulfide, carbon disulfide, styrene, etc.) in real time. The outlet detector is located at the outlet of the secondary absorption + bio-coupling unit to detect the emission concentration of odorous waste gas (including VOCs, odor, ammonia, trimethylamine, hydrogen sulfide, methanethiol, dimethyl sulfide, dimethyl disulfide, carbon disulfide, styrene, etc.) in real time. The control system is connected to the inlet detector, outlet detector, and the dosing devices, circulation pumps, and atomizing nozzles of the primary enhanced absorption unit and the secondary absorption + bio-coupling unit. It adjusts the operation of the dosing device, circulation pump, and atomizing nozzles according to the real-time concentration of odorous waste gas at the inlet and outlet, and uses a neural network to find the optimal combination of operating parameters to meet the emission standards with the lowest energy and material consumption.

[0044] Example 1

[0045] This embodiment adopts Figure 1 The illustrated integrated water-air treatment system, featuring enhanced absorption coupled with biological treatment, is used to treat odorous waste gas from a wastewater treatment plant; the initial odor concentration is 7244 mg / m³ (dimensionless), and VOCs are 73 mg / m³. 3 The specific process is as follows:

[0046] The odorous waste gas first enters the primary enhanced absorption unit, which is equipped with a spray device. Under the action of the composite absorbent, the odorous waste gas is initially purified. After being treated by the primary enhanced absorption unit, the odorous waste gas enters the secondary absorption + biological coupling unit, where it is further purified under the coupling action of the composite absorbent and microbial agents before being discharged. The primary and secondary water storage tanks are connected by a pipeline with a one-way valve. The saturated absorption tail liquid in the primary water storage tank enters the secondary water storage tank.

[0047] The packing material used in the primary enhanced absorption unit is stainless steel Raschig ring packing; the packing material used in the secondary absorption + bio-coupling unit, by mass percentage, includes: 20% stainless steel Raschig ring packing, 20% ceramsite, 30% activated carbon, and 30% bark.

[0048] The microbial agents for the secondary absorption + biocoupling unit are commercially available sulfur-oxidizing bacteria (Boseathiooxidans) and Pseudomonas (Pseudomonas putida) (mass ratio 1:1).

[0049] The composite absorbent used in the primary enhanced absorption unit and the secondary absorption + bio-coupling unit consists of the following components by mass percentage: 0.1% plant extract, 0.1% fatty alcohol polyoxyethylene ether, 5% ethylene glycol, 0.5% sodium citrate, and the remainder water. The plant extract is prepared using a two-step method: (i) Palm oil is heated at 130°C for 3 hours, then acid is added and stirred at 30°C for 5 hours to acidify to a pH value less than 1. Subsequently, alkali is added for neutralization, and the mixture is stirred at 30°C for 5 hours to obtain the active ingredient. (ii) The surface of the active ingredient is activated by N2 plasma for 5 minutes with a discharge power of 150 W, and then reacted in a 1.5 mol / L acrylic acid methanol solution at 40°C for 1.5 hours.

[0050] After purification, the emission concentrations of the exhaust gas are: odor concentration 309 (dimensionless) and VOCs 1.9 mg / m³. 3 Odor and VOC concentrations decreased by 95.7% and 97.4% respectively, and no wastewater was generated.

[0051] Example 2

[0052] This embodiment uses the same system and process as Example 1 for treating odorous gases. The difference between this embodiment and Example 1 is that the composition ratio of the composite absorbent and the buffer are different, while other process conditions remain the same. The components of the composite absorbent used in this embodiment, by mass percentage, are: 0.05% plant extract, 0.05% fatty alcohol polyoxyethylene ether, 8% ethylene glycol, 1% sodium acetate, and the balance being water.

[0053] The initial odor concentration treated in this embodiment was 9772 (dimensionless), and VOCs were 58 mg / m³. 3 The purified exhaust gas concentrations were: odor concentration 417 (dimensionless) and VOCs 3.6 mg / m³. 3 Odor and VOC concentrations decreased by 95.7% and 93.8% respectively, and no wastewater was generated.

[0054] Example 3

[0055] This embodiment refers to the system and process of Example 1 for treating odorous gases. The difference from Example 1 is that the packing material used in the secondary absorption + biological coupling unit in this embodiment includes, by mass percentage: 20% stainless steel Raschig ring packing, 20% volcanic rock, 30% zeolite, and 30% coconut shell. Other process conditions remain unchanged.

[0056] The initial odor concentration treated in this embodiment was 5495 (dimensionless), and VOCs were 28 mg / m³. 3 The purified exhaust gas concentrations are: odor concentration 309 (dimensionless) and VOCs 1.9 mg / m³. 3Odor and VOC concentrations decreased by 94.4% and 93.2% respectively, and no wastewater was generated.

[0057] Comparative Example 1

[0058] This comparative example uses the same system and process as Example 1 to treat odorous gases. The difference from Example 1 is that the composite absorbent used in this comparative example is replaced with water, while other process conditions remain unchanged.

[0059] The initial odor concentration in this comparative treatment was 5495 (dimensionless), and VOCs were 86 mg / m³. 3 The purified exhaust gas concentrations are: odor concentration 2344 (dimensionless) and VOCs 40 mg / m³. 3 Odor concentration and VOCs concentration decreased by 57.3% and 53.5% respectively, and no wastewater was generated.

[0060] Comparative Example 2

[0061] This comparative example treats odorous gases using the same system and process as Example 1. The difference between this comparative example and Example 1 is that the composite absorbent used is different, while other process conditions remain unchanged. The composite absorbent used in this comparative example consists of 0.1% plant extract, 0.1% fatty alcohol polyoxyethylene ether, 5% ethylene glycol, 0.5% sodium citrate, and the balance water. The plant extract is directly derived from the active ingredient in the invention patent CN 114210174 A without further treatment (i.e., the plant extract in this comparative example is prepared by the following steps: palm oil is heated at 130°C for 3 hours, then acid is added and stirred at 30°C for 5 hours to acidify to a pH value less than 1, followed by neutralization with alkali, and then stirred at 30°C for 5 hours).

[0062] The initial odor concentration in this comparative treatment was 2344 (dimensionless), and VOCs were 59 mg / m³. 3 The purified exhaust gas concentrations are: odor concentration 724 (dimensionless) and VOCs 16 mg / m³. 3 Odor and VOC concentrations decreased by 69.1% and 72.9% respectively, and no wastewater was generated.

[0063] Comparative Example 3

[0064] This comparative example uses the same system and process as Example 1 to treat odorous gases. The difference from Example 1 is that the secondary absorption + biological coupling unit in this comparative example does not use microbial agents, while other process conditions remain unchanged.

[0065] The initial odor concentration in this comparative treatment was 7244 (dimensionless), and VOCs were 96 mg / m³. 3 The purified exhaust gas concentrations are: odor concentration 2344 (dimensionless), VOCs 35 mg / m³.3 Odor concentration and VOCs concentration decreased by 67.6% and 63.5% respectively, and wastewater was generated from absorption.

[0066] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A water-air integrated treatment system with enhanced absorption coupled with biological treatment, characterized in that, It includes a primary enhanced absorption unit, a secondary absorption + bio-coupling unit, and a control unit: The primary enhanced absorption unit includes a primary circulating pump, a primary atomizing nozzle, a primary water storage tank, a primary dosing device, a primary pH meter, a temperature and humidity sensor, a primary packed bed, an air inlet, a water storage tank connecting pipe, and a one-way valve; wherein the primary dosing device and the primary pH meter are connected to the primary water storage tank, the inlet of the primary circulating pump is connected to the primary water storage tank, the outlet of the primary circulating pump is connected to the primary atomizing nozzle, the primary atomizing nozzle is located above the primary packed bed, and the temperature and humidity sensor is located on the air inlet pipe; The secondary absorption + bio-coupling unit includes a secondary circulation pump, a secondary atomizing nozzle, a secondary water storage tank, a secondary dosing device, a secondary pH meter, a secondary packed bed, an aeration device, a liquid redistributor, and an aeration outlet; The secondary dosing device and secondary pH meter are connected to the secondary water storage tank; the inlet of the secondary circulation pump is connected to the secondary water storage tank; the outlet of the secondary circulation pump is connected to the secondary atomizing nozzle; and the secondary atomizing nozzle is located above the secondary packing bed. The gas distribution device is located at the bottom of the secondary absorption + biological coupling unit, and the liquid redistributor is located at the top of the secondary packing bed. The bottom of the primary enhanced absorption unit is connected to the bottom of the secondary absorption + bio-coupling unit; The primary water storage tank and the secondary water storage tank are connected by a water storage tank connecting pipe; The control unit includes an air inlet detector, an air outlet detector, and a control system.

2. The integrated water and air treatment system with enhanced absorption coupled with biological treatment according to claim 1, characterized in that, The packing material used in the primary packed bed is an absorbent packing material, specifically one or more of ceramic, stainless steel, or plastic packing materials.

3. The integrated water and air treatment system with enhanced absorption coupled with biological treatment according to claim 1, characterized in that, The secondary packed bed uses a combination of absorbent packing, ceramsite / volcanic rock, activated carbon / zeolite, and bark / coconut shell; by mass ratio, it includes: 10-30% absorbent packing, 20-40% ceramsite / volcanic rock, 10-30% activated carbon / zeolite, and 10-30% bark / coconut shell; wherein the absorbent packing is one or more of ceramic, stainless steel, or plastic packing.

4. The integrated water and air treatment system with enhanced absorption coupled with biological treatment according to claim 1, characterized in that, The secondary packing bed has four layers, and each packing layer is equipped with a liquid redistributor at the top; microbial agents are loaded onto the packing material of the secondary packing bed.

5. A water-air integrated treatment method with enhanced absorption coupled with biological treatment, wherein the odorous waste gas to be treated sequentially enters a primary enhanced absorption unit and a secondary absorption + biological coupling unit for purification; characterized in that, Includes the following steps: (1) The malodorous waste gas first enters the primary enhanced absorption unit. The sprayed composite absorbent comes into contact with the malodorous gas to achieve preliminary purification of the malodorous gas, while generating saturated absorption tail liquid. (2) The odorous gas after preliminary purification flows to the bottom of the secondary absorption + biological coupling unit and is evenly fed into the secondary packing bed through the gas distribution device at the bottom of the secondary absorption + biological coupling unit; the odorous waste gas flows from bottom to top through the secondary packing bed to the outlet. When the odorous waste gas passes through the secondary packing bed, it comes into contact with the microbial agent loaded on the packing. At the same time, the composite absorbent sprayed from top to bottom comes into contact with the odorous waste gas in the opposite direction. Under the coupling effect of the composite absorbent and the microbial agent, the odorous waste gas is deeply purified and discharged. (3) The saturated absorption tail liquid generated in the primary enhanced absorption unit enters the secondary storage tank of the secondary absorption + biological coupling unit through the pipeline and is sprayed onto the secondary packing bed. The odor and organic components in the saturated absorption tail liquid are purified by the microbial agents on the packing. The composite absorbents in the primary enhanced absorption unit and the secondary absorption + bio-coupling unit are composed of the following components by mass percentage: 0.01-2% plant extract, 0.01-2% surfactant, 1-10% cosolvent, 0.1-2% buffer, and the balance water.

6. The integrated water and air treatment method according to claim 5, characterized in that, The plant extract is prepared by the following step (A) or step (B): (A) The active ingredient is modified by at least one of O2, N2, NH3 or CF4 plasma; (B) The active ingredient is first surface-treated with Ar or N2 plasma, and then reacted in a 0.5-2.5 mol / L acrylic acid methanol solution at 20-60℃ for 0.5-5 hours; The active ingredients described in steps (A) and (B) are obtained by the following steps: heating and dehydrating one or more of soybean oil, palm oil, corn oil, peanut oil, olive oil, rapeseed oil, safflower seed oil, sunflower seed oil, canola seed oil, sea buckthorn seed oil, tea oil, sacha inchi oil, linseed oil, argan oil, and walnut oil; then adding acid and stirring continuously; then adding alkali solution and stirring continuously to obtain the active ingredients.

7. The integrated water and air treatment method according to claim 6, characterized in that, The modification treatment in step (A) takes 1-10 min and the discharge power is 5-500 W; the activation surface treatment in step (B) takes 1-10 min and the discharge power is 5-500 W.

8. The integrated water and air treatment method according to claim 5, characterized in that, The surfactant is nonionic, specifically one or more of fatty alcohol polyoxyethylene ether, alkyl glycoside, fatty acid ethanolamide, and polysorbate; the cosolvent is one or more of ethanol, isopropanol, butanol, and ethylene glycol; and the buffer is one or more of citrate, phosphate, and acetate.

9. The integrated water and air treatment method according to claim 5, characterized in that, The microbial agent is one or more of sulfur-oxidizing bacteria, nitrosomonas, spore-forming bacteria, and pseudomonas.

10. The integrated water and air treatment method according to claim 5, characterized in that, The method uses a control system to analyze the concentration of odorous exhaust gas at the inlet and outlet in real time, and controls the operation of the dosing device, circulating pump, and atomizing nozzle to ensure that the exhaust gas meets emission standards.

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