Sewage plant tail water deep purification and greenhouse gas cooperative control system and method based on two-stage dynamic electrolysis vertical flow constructed wetland

Abstract

The invention discloses a sewage plant tail water deep purification and greenhouse gas cooperative control system and method based on two-stage dynamic electrolysis vertical flow constructed wetlands, and the system comprises two electrolysis constructed wetlands which are the same in structure and different in operation condition, namely a pulse vertical flow electrolysis wetland and a voltage stabilization vertical flow electrolysis wetland. The tail water of the sewage plant firstly enters the pulse vertical flow electrolytic wetland after staying in the reservoir, whether the sewage passing through the pulse vertical flow electrolytic tank preliminarily reaches the standard or not is judged through the intelligent monitoring system, the flow direction of the sewage is controlled through the conversion valve, and the sewage entering the stable-pressure vertical flow electrolytic wetland is deeply purified; water quality data and greenhouse gas emission can be dynamically and accurately monitored through the two-stage electrolysis constructed wetland, the water quality is scientifically and accurately monitored and the sewage treatment capacity of the wetland is allocated by utilizing an intelligent monitoring system, and the stable standard reaching of the water quality and low-carbon operation are ensured; the method has the advantages of high long-term management benefit, convenience in operation, high regulation and control efficiency, stable performance, energy conservation, emission reduction and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of water ecological restoration, and particularly relates to a sewage treatment plant tail water advanced purification and greenhouse gas collaborative control system and method based on a two-stage dynamic electrolytic vertical flow constructed wetland. Background Art

[0002] With the acceleration of economic development and urbanization, the sewage discharge is increasing day by day. Although sewage treatment plants conduct primary treatment on sewage and remove most of the suspended solids and some organic matters, the tail water still contains a certain amount of pollutants, such as nitrogen, phosphorus, trace organic matters, etc. Direct discharge will pose a threat to the water ecological environment. Traditional advanced tail water treatment technologies, such as chemical precipitation, activated carbon adsorption, etc., although they can effectively remove some pollutants, have problems such as high cost and easy generation of secondary pollution. Although biological treatment technologies are relatively environmentally friendly, they have poor adaptability to changes in water quality and quantity. Therefore, it is urgent to develop an efficient, low-cost, environmentally friendly and highly adaptable secondary tail water treatment technology. As an ecological treatment technology, electrolytic constructed wetland has unique advantages. It utilizes the synergistic effects of plants, microorganisms, soil, etc. in the natural ecological system to purify sewage. The roots of plants can absorb pollutants, microorganisms can degrade organic substances, and the soil plays a role in filtration and adsorption. Compared with traditional technologies, the construction and operation costs of constructed wetlands are low, the maintenance and management are simple, and it can improve the surrounding ecological environment, having good ecological, economic and social benefits. Applying constructed wetlands to the secondary treatment of sewage treatment plant tail water is an important way to solve the current tail water discharge problem and achieve sustainable utilization of water resources.

[0003] The patent application document with the application number CN202411799478.5 discloses a multi-stage constructed wetland-ecological pond system for synchronous enhanced removal of nitrogen and phosphorus. In the present invention, there are a first-stage constructed wetland, a second-stage ecological pond and a third-stage constructed wetland connected in series by dropping. Both the first-stage constructed wetland and the third-stage constructed wetland are horizontal subsurface flow constructed wetlands; wetland plants are planted in the first-stage constructed wetland and the third-stage constructed wetland; ecological pond plants are planted on a floating raft in the second-stage ecological pond, a non-woven fabric is arranged below the floating raft, and microalgae are enriched on the non-woven fabric. In the present invention, by using the alternating "anaerobic / anoxic-aerobic-anaerobic / anoxic" environment formed by each stage of the system, the removal of oxidized and reduced nitrogen and the absorption and removal of phosphorus are strengthened. The removal rate of ammonia nitrogen can reach 98%, the removal rate of nitrate nitrogen can reach 98.8%, the removal rate of total nitrogen can reach 98.07%, the removal rate of COD can reach 85.02%, and the removal rate of total phosphorus can reach 78%, having broad application prospects. However, it has no greenhouse gas emission monitoring measures.

[0004] The patent application document with the application number CN202411741271.2 discloses a tail water constructed wetland structure for energy conservation and carbon reduction under low temperature conditions, which includes: a pool body, including an upstream wetland pool and a downstream wetland pool connected to the upstream wetland pool. A filter plate is arranged at the connection between the upstream wetland pool and the downstream wetland pool, and a water outlet space is arranged on the side of the downstream wetland pool away from the upstream wetland pool; a water distribution component, including an inlet water pipe penetrating through the side of the upstream wetland pool away from the downstream wetland pool, a heat preservation chamber connected to the inlet water pipe, a plurality of water distribution flower pipes connected to the heat preservation chamber, and an air vent horn pipe branched out from each water distribution flower pipe. The nozzle of the air vent horn pipe extends out of the upstream wetland pool; a wind power aeration device; an integrated electro-thermal conversion device, including a heat collection element, an energy storage component electrically connected to the heat collection element, and a generator set electrically connected to the energy storage component. The generator set is connected with a heater, and the heater is arranged outside and / or inside the heat preservation chamber. This application can reduce the required energy consumption while ensuring the operation effect of the tail water constructed wetland in winter. However, it has no greenhouse gas emission monitoring measures.

[0005] The invention with the application number CN202411639009.7 discloses an artificial wetland microbial fuel cell coupling device based on a novel three-dimensional electrode, belonging to the technical field of sewage treatment. The device includes a shell, and a bottom layer, an anode layer, a middle layer and a cathode layer are sequentially arranged in the shell from bottom to top. Among them, the bottom layer is filled with coarse gravel, and the middle layer is filled with fine gravel; the anode layer is composed of a plurality of horizontally arranged titanium tubes and a titanium mesh for connecting the titanium tubes in parallel; both ends of the titanium tube are provided with openings, and through holes are arrayed on the titanium tube. The inside of the titanium tube is filled with a crimped graphite felt core body; the graphite felt core body can not only be used as a conductive material to strengthen the process, but also as a support material. Compared with the anode cage structure composed of stainless steel mesh, the bearing strength is higher; the resistance of metal titanium is lower than that of stainless steel mesh, which is beneficial to electron transmission and improving the electron transfer efficiency, and can effectively improve the energy recovery efficiency and pollutant removal efficiency of the artificial wetland microbial fuel cell coupling device. However, it has no greenhouse gas emission monitoring measures. Summary of the Invention

[0006] Inventive Purpose: Aiming at the problem that the tail water of sewage treatment plants still contains pollutants such as nitrogen, phosphorus, and trace organic matter, and direct discharge will pose a threat to the water ecological environment, the present invention provides a sewage treatment plant tail water deep purification and greenhouse gas collaborative control system and method based on a two-stage dynamic electrolytic vertical flow constructed wetland. The present invention can dynamically and accurately monitor water quality data and monitor greenhouse gas emissions through the two-stage electrolytic constructed wetland, use the unique anode and cathode microorganisms of the electrolytic wetland to deeply purify the tail water of sewage treatment plants and reduce greenhouse gas emissions, promote the healthy development of the urban environment, use the intelligent monitoring system to scientifically and accurately monitor water quality and allocate the sewage treatment volume of the wetland, ensure the stable compliance of water quality and low-carbon operation, and has the advantages of high long-term management benefits, convenient operation, high regulation efficiency, stable performance, energy conservation and emission reduction.

[0007] Technical solution: The object of the present invention is achieved by the following technical solutions:

[0008] A sewage treatment plant effluent advanced purification and greenhouse gas synergistic control system based on a two-stage dynamic electrolytic vertical flow constructed wetland, comprising a reservoir (3-1), a pulsed vertical flow electrolytic wetland (1), a reservoir (3-2), a voltage-stabilized vertical flow electrolytic wetland (2) and a stabilization pond (4) designed in sequence. The reservoir (3-1) can balance the influent flow of the sewage treatment plant effluent, cope with the unevenness of sewage discharge, avoid the unstable operation of the subsequent treatment units due to water volume impact, and provide a certain amount of buffer water when the subsequent equipment is under maintenance or a sudden failure occurs, ensuring the basic operation of the device; at the same time, the reservoir (3-1) needs to receive the water quality determined by the intelligent monitoring system (5-1) as not initially meeting the standards and enter the pulsed electrolytic wetland pond (1) again for purification. The reservoir (3-2) receives the effluent from the pulsed vertical flow electrolytic wetland after preliminary treatment and meets the standards. At the same time, the reservoir (3-2) needs to receive the water quality determined by the intelligent monitoring system (6-1) as not meeting the standards and enter the voltage-stabilized vertical flow electrolytic wetland (2) again for purification.

[0009] Step 1): According to the tail water volume Q of the nearby sewage treatment plant that the constructed wetland is planned to receive and the main assessment indicators in Class III water of the Surface Water Environment Quality Standard (GB3838-2002) (CODcr ≤ 20 mg / L, NH3-N ≤ 1.0 mg / L, TP ≤ 0.2 mg / L), optimize and design the area A1 of the pulsed vertical flow electrolytic wetland (1) and the area A2 of the voltage-stabilized vertical flow electrolytic wetland (2).

[0010]

[0011] Q: Tail water flow (m 3 / d)

[0012] HLR pulse = K p *HLR 传统 : Pulsed electrolytic hydraulic loading rate (K p is the electrolytic strengthening coefficient, taking 2 - 3. The HLR of the traditional vertical flow wetland is about 0.5 - 1.0 m 3 / (m 2 ·d))

[0013]

[0014] Q: Tail water flow (m 3 / d)

[0015] β: Electrolytic denitrification efficiency coefficient, taking 5 - 20 g / (m 2 ·d))

[0016] γ: Anodic dissolution phosphorus coefficient, taking values from 0.15 to 0.25 g / (A·h)

[0017] I: Working current, taking values from 50 to 200 A / m 2

[0018] Step 2), The tail water of the sewage treatment plant is temporarily stored in the reservoir (3 - 1), pumped into the pulsed vertical flow electrolytic wetland (1) by the water pump (1 - 4). The duty cycle of the pulsed power supply (1 - 1) is α, unit: %; the frequency is β, unit: Hz; the voltage is γ, unit: V. The tail water enters the water distribution horizontal pipe (1 - 2) and the water distribution vertical pipe (1 - 6) in sequence, and is evenly distributed by a number of mist sprinkler heads (1 - 8). Then the tail water seeps into the cathode layer (1 - 9), the anode layer (1 - 10), and the supporting layer (1 - 11) in sequence, and then flows to the intelligent monitoring system (5 - 1). There are three cathode sampling ports (1 - 12) opened on the side of the cathode and three anode sampling ports (1 - 13) opened on the side of the anode. The water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system (5 - 1). The water quality items are sorted according to the serial numbers of the Class III water standard of the "Surface Water Environment Quality Standard" (GB3838 - 2002). The first item index is water temperature, the second item index is pH, the third item index is dissolved oxygen... the 24th item index is coliform group (number / L). The real - time water quality of the cathode area is The real - time water quality of the anode area is The photoacoustic spectroscopy - type greenhouse gas sensor (5 - 5) is installed at the three cathode sampling ports (1 - 12) and the three anode sampling ports (1 - 13) to monitor the emissions of the three main greenhouse gases (CH4, N2O, CO2) in real - time.

[0019] Step 3), The intelligent monitoring system (5 - 1) needs to judge whether the effluent water quality of the pulsed vertical flow electrolytic wetland (1) reaches the preliminary purification standard, and the judgment method is as shown in formula (7)

[0020]

[0021] Note: C in , i : The influent concentration of the i - th item index (mg / L) (the first item index is BOD, the second item index is COD, the third item index is SS, the fourth item index is TN, the fifth item index is TP)

[0022] C1, i : The effluent concentration of the first - stage (mg / L)

[0023] w i : Index weight coefficient (w BOD = 0.25, w COD = 0.20, w SS = 0.20, wTN = 0.15, w TP = 0.20)

[0024] E: Comprehensive water quality treatment index

[0025] Condition 1: If the output is 1, the intelligent monitoring system (5-1) controls the tail water flow direction to the reservoir (3-2) by controlling the steering valve (5-2).

[0026] Condition 2: If the output is 0, the intelligent monitoring system (5-1) controls the tail water to flow into the return pipe (5-4) and re-enter the reservoir (3-1) through the control of the steering valve (5-2). The flow meter (5-3) is set on the return pipe (5-4) to detect the return water volume Q 1回 .

[0027] Step 4): The tail water reaching the preliminary purification standard enters the reservoir (3-2), is pumped into the steady-pressure vertical-flow electrolytic wetland (1) by the water pump (2-4), and the voltage is η, with the unit of V. The tail water successively enters the water distribution horizontal pipe (2-1) and the water distribution vertical pipe (2-4), and is evenly distributed by a number of mist sprinkler nozzles (2-5). Then the tail water successively infiltrates into the cathode layer (2-9), the anode layer (2-10), and the supporting layer (2-11), and then flows to the intelligent monitoring system (6-1). There are three cathode sampling ports (2-12) opened on the side of the cathode and three anode sampling ports (2-13) opened on the side of the anode. The water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system (6-1). The first index is water temperature, the second index is pH, the third index is dissolved oxygen..., and the 24th index is coliform group (number / L). The real-time water quality in the cathode area is The real-time water quality in the anode area is The photoacoustic spectroscopy type greenhouse gas sensor (6-5) is installed at the three cathode sampling ports (2-12) and the three anode sampling ports (2-13) to monitor the emissions of the three main greenhouse gases (CH4, N2O, CO2) in real time.

[0028] Step 5): The intelligent monitoring system (6-1) needs to judge whether the effluent water quality of the steady-pressure vertical-flow electrolytic wetland (2) reaches the surface water class III standard, and the judgment method is as shown in formula (8)

[0029]

[0030] Note: C i : The effluent concentration of the i-th index (mg / L) (sort the water quality items according to the serial number of the class III water standard of the "Surface Water Environment Quality Standard" (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen..., and the 24th index is coliform group (number / L))

[0031] C i0 : Surface Class III water standard for the i-th indicator (mg / L)

[0032] C gas Daily average emission concentration of each gas (mg / m 3 )

[0033] W: Comprehensive gas treatment index

[0034] Condition 1: If the output is 1, the intelligent monitoring system (6-1) controls the flow direction of the tail water to the stabilization pond (4) by controlling the steering valve (6-2).

[0035] Condition 2: If the output is 0, the intelligent monitoring system (6-1) controls the tail water to flow into the return pipe (6-4) and re-enter the reservoir (3-2) by controlling the steering valve (6-2). The flow meter (6-3) is set on the return pipe (6-4) to detect the return water volume Q 2回 .

[0036] Compared with the prior art, the advantages of the present invention are as follows:

[0037] (1) It can dynamically and accurately monitor the water quality data of the water body to be purified and monitor the greenhouse gas emissions.

[0038] (2) The intelligent monitoring system is used to scientifically and accurately monitor the water quality and allocate the sewage treatment volume of the wetland, ensuring stable water quality compliance and low-carbon operation.

[0039] (3) High long-term management benefits, convenient operation, high regulation efficiency, stable performance, energy conservation and emission reduction. Brief Description of the Drawings

[0040] Figure 1 Floor plan of a sewage treatment plant tail water deep purification and greenhouse gas collaborative control system based on a double-stage dynamic electrolytic vertical flow constructed wetland;

[0041] Figure 2 I-I sectional view of a sewage treatment plant tail water deep purification and greenhouse gas collaborative control system based on a double-stage dynamic electrolytic vertical flow constructed wetland;

[0042] Figure 3 II-II sectional view of a sewage treatment plant tail water deep purification and greenhouse gas collaborative control system based on a double-stage dynamic electrolytic vertical flow constructed wetland;

[0043] Figure 4 III-III sectional view of a sewage treatment plant tail water deep purification and greenhouse gas collaborative control system based on a double-stage dynamic electrolytic vertical flow constructed wetland;

[0044] Figure 5Flow chart of the regulation method for the advanced purification of the tail water of a sewage treatment plant and the greenhouse gas collaborative control system based on a two-stage dynamic electrolytic vertical flow constructed wetland;

[0045] Figure 6 This is the connection block diagram of the control system of the present invention.

[0046] In the figure: pulsed vertical flow electrolytic wetland - 1, pulsed power supply - 1 - 1, horizontal water distribution pipe Ⅰ - 1 - 2, wire Ⅰ - 1 - 3, water pump Ⅰ - 1 - 4, resistor Ⅰ - 1 - 5, vertical water distribution pipe Ⅰ - 1 - 6, ventilation riser Ⅰ - 1 - 7, mist sprinkler Ⅰ - 1 - 8, cathode Ⅰ - 1 - 9, anode Ⅰ - 1 - 10, supporting layer Ⅰ - 1 - 11, cathode sampling port Ⅰ - 1 - 12, anode sampling port Ⅰ - 1 - 13, intelligent monitoring system Ⅰ - 5 - 1, steering valve Ⅰ - 5 - 2, flowmeter Ⅰ - 5 - 3, return pipe Ⅰ - 5 - 4, photoacoustic spectroscopy type greenhouse gas sensor Ⅰ - 5 - 5;

[0047] Steady - pressure vertical flow electrolytic wetland - 2, horizontal water distribution pipe Ⅱ - 2 - 1, water pump Ⅱ - 2 - 2, ventilation riser Ⅱ - 2 - 3, vertical water distribution pipe Ⅱ - 2 - 4, mist sprinkler Ⅱ - 2 - 5, wire Ⅱ - 2 - 6, steady - pressure power supply - 2 - 7, resistor Ⅱ - 2 - 8, cathode Ⅱ - 2 - 9, anode Ⅱ - 2 - 10, supporting layer Ⅱ - 2 - 11, cathode sampling port Ⅱ - 2 - 12, anode sampling port Ⅱ - 2 - 13, intelligent monitoring system Ⅱ - 6 - 1, steering valve Ⅱ - 6 - 2, flowmeter Ⅱ - 6 - 3, return pipe Ⅱ - 6 - 4, photoacoustic spectroscopy type greenhouse gas sensor Ⅱ - 6 - 5;

[0048] Storage pond Ⅰ - 3 - 1, storage pond Ⅱ - 3 - 2, stabilization pond - 4. Detailed implementation manners

[0049] The technical solution of the present invention is further introduced through the following specific embodiments.

[0050] An advanced purification of the tail water of a sewage treatment plant and greenhouse gas collaborative control system based on a two - stage dynamic electrolytic vertical flow constructed wetland includes a pulsed vertical flow electrolytic wetland 1, a steady - pressure vertical flow electrolytic wetland 2, a storage pond 3, a stabilization pond 4, a primary control system 5, and a secondary control system 6. The pulsed vertical flow electrolytic wetland 1 and the steady - pressure vertical flow electrolytic wetland 2 have the same organizational structure and connection relationship, but the difference is that they use different types of power supplies, and thus achieve different functions; the pulsed power supply and resistor in the pulsed vertical flow electrolytic wetland 1 periodically output pulsed voltages to promote the electrolysis reaction; the steady - pressure power supply and resistor in the steady - pressure vertical flow electrolytic wetland 2 provide a steady voltage and have the ability to adjust the voltage to optimize the electrode reaction.

[0051] Before and after the pulsed vertical-flow electrolytic wetland, there are a reservoir Ⅰ 3-1 and a reservoir Ⅱ 3-2 respectively. The tail water of the sewage treatment plant to be treated first flows into the reservoir Ⅰ 3-1, where the influent flow of the tail water of the sewage treatment plant can be balanced, coping with the unevenness of sewage discharge, avoiding the unstable operation of the subsequent treatment units due to water volume impact, providing a certain amount of buffer water during the subsequent equipment maintenance or sudden failure, and ensuring the basic operation of the device. At the same time, the reservoir Ⅰ 3-1 needs to receive the water quality determined by the intelligent monitoring system Ⅰ 5-1 as not initially meeting the standard and enter the pulsed electrolytic wetland pond 1 again for purification. The reservoir Ⅱ 3-2 is used to receive the tail water that has been initially treated and met the standard by the pulsed vertical-flow electrolytic wetland treatment. At the same time, the reservoir Ⅱ needs to receive the water quality determined by the intelligent monitoring system 6-1 as not meeting the standard and enter the pressure-stabilized vertical-flow electrolytic wetland 2 again for purification.

[0052] Among them, the tail water of the sewage treatment plant meets the secondary standard for the discharge of tail water from urban sewage treatment plants (COD ≤ 100 mg / L, NH3-N ≤ 25 mg / L, TP ≤ 3 mg / L).

[0053] The pulsed vertical-flow electrolytic wetland 1 includes a pulsed power supply 1-1, a water distribution horizontal pipe Ⅰ 1-2, a wire Ⅰ 1-3, a water pump Ⅰ 1-4, a resistor Ⅰ 1-5, a water distribution vertical pipe Ⅰ 1-6, an air ventilation vertical pipe Ⅰ 1-7, a mist sprinkler Ⅰ 1-8, a cathode Ⅰ 1-9, an anode Ⅰ 1-10, a supporting layer Ⅰ 1-11, a cathode sampling port Ⅰ 1-12, and an anode sampling port Ⅰ 1-13.

[0054] The sewage in the reservoir Ⅰ 3-1 is pumped into the water distribution horizontal pipe Ⅰ 1-2 and the water distribution vertical pipe Ⅰ 1-6 by the water pump Ⅰ 1-4. The water distribution horizontal pipe Ⅰ 1-2 and the water distribution vertical pipe Ⅰ 1-6 are arranged on the surface of the filter material of the pulsed vertical-flow electrolytic wetland. The tail water is evenly distributed through the mist sprinkler Ⅰ 1-8 on the water distribution vertical pipe Ⅰ 1-6. The water droplets sprayed by this water distribution method are small, and the formed water mist has a large contact area with the air, which can increase the dissolved oxygen content in the water, provide more sufficient oxygen for aerobic microorganisms in the wetland, promote the decomposition and transformation of organic matter, and is not easy to be blocked. The tail water passes through the cathode Ⅰ 1-9, the anode Ⅰ 1-10, the supporting layer Ⅰ 1-11 from top to bottom and then passes through the intelligent monitoring system Ⅰ 5-1. There are several air ventilation vertical pipes Ⅰ 1-7 arranged in the pulsed electrolytic wetland pond 1, which can carry out gas exchange, balance pressure, prevent odor generation, and cope with flood exceeding the standard.

[0055] The cathode I 1-9 and the anode I 1-10 are connected by wire I 1-1, and a pulse power supply 1-1 and a resistor I 1-2 are arranged on the wire I 1-1. The pulse power supply 1-1 and the resistor I 1-5 can periodically output pulse voltage to promote the electrolysis reaction, reduce energy consumption, reduce electrode loss, inhibit filler blockage, and decompose refractory substances. The duty cycle of the pulse power supply 1-1 is α, in %; the frequency is β, in Hz; and the voltage is γ, in V.

[0056] The cathode I 1-9 and the anode I 1-10 have the same filter material filling. Both are filled with coconut shell activated carbon (particle size 3 cm to 5 cm), and a carbon felt-stainless steel mesh is placed in the middle as the electrode. The anode I 1-10 and the cathode I 1-9 are respectively connected to the copper wire I 1-1. The wire connection points submerged in the wetland filter material are first coated with conductive glue, and then coated with epoxy resin after waiting for air drying to prevent the wire from being directly connected to water and causing a short circuit.

[0057] In the pulsed vertical flow electrolytic wetland 1, three cathode sampling ports I 1-12 and three anode sampling ports I 1-13 are provided for the cathode I 1-9 and the anode I 1-10 to ensure data accuracy. Water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system 5-1. According to the serial number of the Class III water standard in the "Surface Water Environment Quality Standard" (GB3838-2002), the water quality items are sorted. The concentration of the i-th index at the three cathode sampling ports I 1-12 is X 1i 、X 2i 、X 3i ; The concentration of the i-th index at the three anode sampling ports I 1-13 is Y 1i 、Y 2i 、Y 3i ; Then the concentration X t of the i-th index of the cathode 1-9 is as shown in Equation (3), and the concentration Y t of the i-th index of the anode (1-10) is as shown in Equation (4); 1 ≤ i ≤ 24

[0058]

[0059] The intelligent monitoring system I 5-1 is on the outlet pipe of the pulsed vertical flow electrolytic wetland 1, and it can judge whether the effluent water quality of the pulsed vertical flow electrolytic wetland (1) reaches the preliminary purification standard. The judgment method is as shown in Equation (7)

[0060]

[0061] Note: C in , i : Inlet concentration of the i-th index (mg / L) (the first index is BOD, the second index is COD, the third index is SS, the fourth index is TN, and the fifth index is TP)

[0062] C1, i : The concentration of the first-stage effluent (mg / L)

[0063] w i : Index weight coefficient (w BOD = 0.25, w COD = 0.20, w SS = 0.20, w TN = 0.15, w TP = 0.20)

[0064] E: Comprehensive water quality treatment index

[0065] On the water pipe behind the intelligent monitoring system I 5-1, there is also a steering valve I 5-2. If the output is 1, the intelligent monitoring system I controls the tail water to flow to the reservoir I 3-2 through the return pipe I 5-4 by controlling the steering valve I to achieve cyclic purification; if the output is 0, the intelligent monitoring system I 5-1 controls the tail water to flow into the return pipe I 5-4 and then enter the reservoir II 3-1 again by controlling the steering valve I 5-2. The flowmeter I 5-3 is arranged on the return pipe I 5-4 to detect the amount of return water.

[0066] A photoacoustic spectroscopy type greenhouse gas sensor I 5-5 is set at the water outlet of the pulsed vertical flow electrolytic wetland 1 and waterproof measures are taken. The photoacoustic spectroscopy type greenhouse gas sensor can monitor the emissions of main greenhouse gases (CH4, N2O, CO2), clarify the emission rates and change trends of greenhouse gases under different operating conditions (such as different electrolysis voltages, pollutant concentrations, etc.) of the electrolytic constructed wetland, master the time and conditions for the appearance of the peaks and troughs of its emissions, and is more easily installed and maintained in the outdoor pilot-scale constructed wetland environment. The organizational structure of the regulated vertical flow electrolytic wetland 2 is the same as that of the pulsed vertical flow electrolytic wetland 1, and the difference between the two lies in the working mode (operating parameters). Specifically, the regulated power supply II 2-7 and the resistor II 2-8 in the regulated vertical flow electrolytic wetland 2 provide regulated voltage, can output current efficiently, have high stability, have the ability to adjust voltage, and optimize the electrode reaction. The voltage is η, with the unit of V.

[0067] The concentration of the i-th index at the three cathode sampling ports II 2-12 of the cathode in the regulated vertical flow electrolytic wetland 2 is A 1i 、A 2i 、A 3i ; The concentration of the i-th index at the three anode sampling ports II 2-13 is B 1i 、B 2i 、B 3i ; Then the concentration A t of the i-th index at the cathode II 2-9 is formula (5), and the concentration B t of the i-th index at the anode II 2-10 is formula (6)

[0068]

[0069] An intelligent monitoring system II 6-2 is provided on the effluent pipeline of the voltage-stabilized vertical-flow electrolytic wetland 2, which is different from the intelligent monitoring system I 5-1 on the effluent pipeline of the pulsed vertical-flow electrolytic wetland 1. The intelligent monitoring system II 6-2 can determine whether the effluent quality of the voltage-stabilized vertical-flow electrolytic wetland 2 meets the surface water class III standard, and the surface water class III standard is the "Surface Water Environment Quality Standard" (GB3838-2002), and determine whether the greenhouse gas emissions meet the standards. The determination method is as shown in formula (8).

[0070]

[0071] Note: C i : Effluent concentration of the i-th index (mg / L) (sort the water quality items according to the serial number of the surface water class III standard of the "Surface Water Environment Quality Standard" (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... the 24th index is coliform group (number / L))

[0072] C i0 : Surface water class III standard of the i-th index (mg / L)

[0073] C gas Daily average emission concentration of each gas (mg / m 3 )

[0074] W: Gas comprehensive treatment index

[0075] If the output is 1, the intelligent monitoring system II 6-1 controls the tail water flow direction to the stabilization pond (4) set behind the voltage-stabilized vertical-flow electrolytic wetland 2 by controlling the steering valve II 6-2 on the effluent pipe;

[0076] If the output is 0, the intelligent monitoring system II 6-1 controls the tail water to flow into the return pipe II 6-4 and enter the reservoir II 3-2 in front of the voltage-stabilized vertical-flow electrolytic wetland 2 again by controlling the steering valve II 6-2 on the effluent pipe. The flowmeter II 6-3 is arranged on the return pipe II 6-4 to detect the return water volume Q 2回 .

[0077] Example 1

[0078] The main water quality assessment indicators of a certain constructed wetland are class III of the "Surface Water Environment Quality Standard" (GB3838-2002) (CODcr ≤ 20 mg / L, NH3-N ≤ 1.0 mg / L, TP ≤ 0.2 mg / L). The planned tail water volume Q m 3 / d.

[0079] Step 1): The tail water volume Q = 1000 m 3 / d received by the constructed wetland planning is used to design the area of the constructed wetland for the three main evaluation indicators: the area A1 of the pulsed vertical flow electrolytic wetland 1, the area A2 of the steady pressure vertical flow electrolytic wetland 2, and HLR pulse = 2 m / d, the electrolytic denitrification efficiency coefficient β = 8.0 g / (m 2 ·d), ΔNH3-N = 10 mg / L, ΔP = 1.5 mg / L;

[0080]

[0081] Q: Tail water flow (m 3 / d);

[0082] HLR pulse = K p *HLR 传统 : Pulsed electrolytic hydraulic loading rate (K p is the electrolytic strengthening coefficient, taking 2 - 3, and the HLR of the traditional vertical flow wetland is about 0.5 - 1.0 m 3 / (m 2 ·d))

[0083]

[0084] Q: Tail water flow (m 3 / d)

[0085] β: Electrolytic denitrification efficiency coefficient, taking 5 - 20 g / (m 2 ·d)

[0086] γ: Anodic phosphorus dissolution coefficient, taking 0.15 - 0.25 g / (A·h)

[0087] I: Working current, taking 50 - 200 A / m 2 .

[0088] Step 2): The tail water of the sewage treatment plant is temporarily stored in the reservoir Ⅰ3-1 and pumped into the pulsed vertical flow electrolytic wetland 1 by the water pump Ⅰ1-4. The duty cycle of the pulsed power supply 1-1 is α = 50%; the frequency is β = 50 Hz; the voltage is γ = 0-1 V. The tail water enters the water distribution horizontal pipe Ⅰ1-2 and the water distribution vertical pipe Ⅰ1-6 in sequence, and is evenly distributed by a number of mist sprinkler heads Ⅰ1-8. Then the tail water seeps into the cathode layer Ⅰ1-9, the anode layer Ⅰ1-10, and the supporting layer Ⅰ1-11 in sequence, and then flows to the intelligent monitoring system Ⅰ5-1. There are three cathode sampling ports Ⅰ1-12 on the side of the cathode and three anode sampling ports Ⅰ1-13 on the side of the anode. The water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system Ⅰ5-1. The water quality items are sorted according to the serial numbers of the Class Ⅲ water standard in the Environmental Quality Standards for Surface Water (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... The 24th index is coliform group (number / L). The real-time water quality in the cathode area and the real-time water quality in the anode area are displayed on the intelligent monitoring system Ⅰ5-1. The photoacoustic spectroscopy type greenhouse gas sensor Ⅰ5-5 is installed at the three cathode sampling ports Ⅰ1-12 and the three anode sampling ports Ⅰ1-13 to monitor and display the emissions of the three main greenhouse gases (CH4, N2O, CO2) in real time.

[0089] Step 3): The intelligent monitoring system Ⅰ5-1 needs to judge whether the effluent water quality of the pulsed vertical flow electrolytic wetland 1 meets the preliminary purification standard according to the water quality comprehensive treatment index E.

[0090]

[0091] Note: C in , i : The influent concentration of the i-th index (mg / L) (the first index is BOD, the second index is COD, the third index is SS, the fourth index is TN, and the fifth index is TP)

[0092] C1, i : The effluent concentration of the first stage (mg / L)

[0093] w i : Index weight coefficient (w BOD = 0.25, w COD = 0.20, w SS = 0.20, w TN = 0.15, w TP = 0.20)

[0094] E: Water quality comprehensive treatment index

[0095] Then the output is 1 according to Equation (7), and the intelligent monitoring system Ⅰ5-1 controls the flow direction of the tail water to the reservoir Ⅱ3-2 by controlling the steering valve Ⅰ5-2.

[0096] Step 4): The tail water reaching the preliminary purification standard enters the reservoir Ⅱ 3-2, and is pumped into the steady-pressure vertical-flow electrolytic wetland 2 by the water pump Ⅱ 2-4 at a voltage of 0.8V. The tail water successively enters the water distribution horizontal pipe Ⅱ 2-1 and the water distribution vertical pipe Ⅱ (2-4), and is evenly distributed by a number of mist spray nozzles Ⅱ 2-5. Then the tail water successively infiltrates into the cathode layer Ⅱ 2-9, the anode layer Ⅱ 2-10, and the supporting layer Ⅱ 2-11, and then flows to the intelligent monitoring system Ⅱ 6-1. There are three cathode sampling ports Ⅱ 2-12 on the side of the cathode and three anode sampling ports Ⅱ 2-13 on the side of the anode. The water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system Ⅱ 6-1. The water quality items are sorted according to the serial numbers of the Class Ⅲ water standard in the Environmental Quality Standards for Surface Water (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... The 24th index is coliform group (number / L). The real-time water quality in the cathode area and the real-time water quality in the anode area are displayed on the intelligent monitoring system 6-1. The photoacoustic spectroscopy type greenhouse gas sensor Ⅱ 6-5 is installed at the three cathode sampling ports Ⅱ 2-12 and the three anode sampling ports Ⅱ 2-13 to monitor the emissions of the three main greenhouse gases (CH4, N2O, CO2) in real time.

[0097] Step 5): The intelligent monitoring system Ⅱ 6-1 judges the effluent water quality of the steady-pressure vertical-flow electrolytic wetland 2 according to formula (8), C i ≤C i0 (i = 1, 2…, 24) and

[0098] Note: C i : Effluent concentration of the i-th index (mg / L) (the water quality items are sorted according to the serial numbers of the Class Ⅲ water standard in the Environmental Quality Standards for Surface Water (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... The 24th index is coliform group (number / L))

[0099] C i0 : Surface Class Ⅲ water standard of the i-th index (mg / L)

[0100] C gas Daily average emission concentration of each gas (mg / m 3 )

[0101] W: Gas comprehensive treatment index

[0102] Then the output is 1, and the intelligent monitoring system Ⅱ 6-1 controls the flow direction of the tail water to the stabilization pond 4 by controlling the steering valve Ⅱ 6-2.

[0103] Example 2

[0104] Step 1): The tail water volume Q = 5000 m 3 / d received by the constructed wetland planning. Design the area of the constructed wetland for the three main evaluation indicators: the area A1 of the pulsed vertical flow electrolytic wetland 1, the area A2 of the constant pressure vertical flow electrolytic wetland 2, HLR pulse = 2.5 m / d, the electrolytic denitrification efficiency coefficient β = 18 g / (m 2 ·d), ΔNH3-N = 12 mg / L, ΔP = 1.3 mg / L

[0105]

[0106] Q: Tail water flow (m 3 / d)

[0107] HLR pulse = K p *HLR 传统 : Pulsed electrolytic hydraulic loading rate (K p is the electrolytic strengthening coefficient, taking 2 - 3. The HLR of the traditional vertical flow wetland is about 0.5 - 1.0 m 3 / (m 2 ·d))

[0108]

[0109] Q: Tail water flow (m 3 / d)

[0110] β: Electrolytic denitrification efficiency coefficient, taking 5 - 20 g / (m 2 ·d))

[0111] γ: Anodic phosphorus dissolution coefficient, taking 0.15 - 0.25 g / (A·h)

[0112] I: Working current, taking 50 - 200 A / m 2

[0113] Step 2): The tertiary treated effluent from the sewage treatment plant is temporarily stored in the reservoir Ⅰ3-1 and pumped into the pulsed vertical flow electrolytic wetland (1) by the pump Ⅰ1-4. The duty cycle of the pulsed power supply 1-1 is α = 50%; the frequency is β = 55 Hz; the voltage is γ = 0.2 - 1 V. The effluent enters the horizontal water distribution pipe Ⅰ1-2 and the vertical water distribution pipe Ⅰ1-6 in sequence, and is evenly distributed by a number of mist spray nozzles Ⅰ1-8. Then the effluent seeps into the cathode layer Ⅰ1-9, the anode layer Ⅰ1-10, and the supporting layer Ⅰ1-11 in sequence, and then flows to the intelligent monitoring system Ⅰ5-1. There are three cathode sampling ports Ⅰ1-12 on the side of the cathode and three anode sampling ports Ⅰ1-13 on the side of the anode. The water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system Ⅰ5-1. The water quality items are sorted according to the serial numbers of the Class Ⅲ water standard in the Environmental Quality Standards for Surface Water (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... the 24th index is coliform group (number / L). The real-time water quality in the cathode area and the anode area is displayed on the intelligent monitoring system Ⅰ5-1. The photoacoustic spectroscopy type greenhouse gas sensor Ⅰ5-5 is installed at the three cathode sampling ports Ⅰ1-12 and the three anode sampling ports Ⅰ1-13 to monitor and display the emissions of the three main greenhouse gases (CH4, N2O, CO2) in real time.

[0114] Step 3): The intelligent monitoring system (5-1) needs to judge whether the effluent quality of the pulsed vertical flow electrolytic wetland (1) meets the preliminary purification standard according to the water quality comprehensive treatment index E.

[0115]

[0116] Note: C in , i : The influent concentration of the i-th index (mg / L) (the first index is BOD, the second index is COD, the third index is SS, the fourth index is TN, the fifth index is TP)

[0117] C1, i : The effluent concentration of the first stage (mg / L)

[0118] w i : Index weight coefficient (w BOD = 0.25, w COD = 0.20, w SS = 0.20, w TN = 0.15, w TP = 0.20)

[0119] E: Water quality comprehensive treatment index

[0120] If the output according to Equation (7) is 1, the intelligent monitoring system Ⅰ5-1 controls the flow direction of the effluent to the reservoir Ⅱ3-2 by controlling the steering valve Ⅰ5-2.

[0121] Step 4): The tail water reaching the preliminary purification standard enters the storage pond II 3-2, and is pumped into the stable vertical flow electrolytic wetland 1 by the water pump II 2-4 with a voltage of 0.85V. The tail water successively enters the water distribution horizontal pipe 2-1 and the water distribution vertical pipe 2-4, and is evenly distributed by a number of mist spray nozzles 2-5. Then the tail water successively infiltrates into the cathode layer 2-9, the anode layer 2-10, and the supporting layer 2-11, and then flows to the intelligent monitoring system 6-1. There are three cathode sampling ports 2-12 on the side of the cathode and three anode sampling ports 2-13 on the side of the anode. The water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system 6-1. The water quality items are sorted according to the serial numbers of the Class III water standard in the Environmental Quality Standards for Surface Water (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... The 24th index is coliform group (per liter). The real-time water quality in the cathode area and the real-time water quality in the anode area are displayed on the intelligent monitoring system 6-1. The photoacoustic spectroscopy type greenhouse gas sensor 6-5 is installed at the three cathode sampling ports 2-12 and the three anode sampling ports 2-13 to monitor the emissions of the three main greenhouse gases (CH4, N2O, CO2) in real time.

[0122] Step 5): The intelligent monitoring system 6-1 judges the effluent water quality of the stable vertical flow electrolytic wetland (2) according to formula (8):

[0123] C i ≤C i0 (i = 1, 2…, 24) and and

[0124] Note: C i : The effluent concentration of the i-th index (mg / L) (the water quality items are sorted according to the serial numbers of the Class III water standard in the Environmental Quality Standards for Surface Water (GB3838-2002). The first index is water temperature, the second index is pH, the third index is dissolved oxygen... The 24th index is coliform group (per liter))

[0125] C i0 : The Class III surface water standard of the i-th index (mg / L)

[0126] C gas The daily average emission concentration of each gas (mg / m 3 )

[0127] W: Gas comprehensive treatment index

[0128] Then the output is 1, and the intelligent monitoring system 6-1 controls the flow direction of the tail water to the stabilization pond 4 by controlling the steering valve 6-2.

Claims

1. A sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland, characterized in that: include: Pulse vertical flow electrolysis wetland (1), voltage-stabilized vertical flow electrolysis wetland (2), water storage tank, stabilization pond (4), primary control system (5), secondary control system (6); The pulse vertical flow electrolysis wetland (1) and the voltage-stabilized vertical flow electrolysis wetland (2) are arranged in series, and a water reservoir is arranged in front and behind the pulse vertical flow electrolysis wetland (1). The front water reservoir is used to stabilize the sewage to be treated, and the rear water reservoir is used to temporarily store the water body preliminarily purified by the pulse vertical flow electrolysis wetland (1); the primary control system (5) and the secondary control system (6) are respectively arranged on the outlet pipes behind the pulse vertical flow electrolysis wetland (1) and the voltage-stabilized vertical flow electrolysis wetland (2); the stabilization pond (4) is arranged behind the secondary control system (6), and the purified water body after continuous treatment by the pulse vertical flow electrolysis wetland (1) and the voltage-stabilized vertical flow electrolysis wetland (2) is output to the stabilization pond (4); the unqualified water body is circulated to the water reservoir in front of the pulse vertical flow electrolysis wetland (1) through the reflux pipe and is repeatedly purified.

2. According to claim 1, a sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland is characterized in that: The pulse vertical flow electrolysis wetland (1) and the voltage-stabilized vertical flow electrolysis wetland (2) have the same organizational structure and connection relationship, the difference being that they use different types of power supplies, and thus achieve different functions; the pulse power supply and resistor of the pulse vertical flow electrolysis wetland (1) periodically output pulse voltage to promote the electrolysis reaction; the voltage-stabilized power supply and resistor in the voltage-stabilized vertical flow electrolysis wetland (2) provide voltage stabilization, have voltage regulation capability, and optimize electrode reactions.

3. A sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland according to claim 1 or 2, characterized in that: The pulse vertical flow electrolysis wetland (1) comprises a pulse power supply, a water distribution horizontal pipe I, a conductor I, a water pump I, a resistor I, a water distribution vertical pipe I, a ventilation riser I, a cathode I, an anode I, and a supporting layer I; The sewage in the water storage tank is pumped into the water distribution horizontal pipe I and the water distribution vertical pipe I through the water pump I. The water distribution horizontal pipe I and the water distribution vertical pipe I are evenly arranged on the shallow surface of the pulse vertical flow electrolysis wetland filter material. The tail water is evenly distributed through the spray nozzle I on the water distribution vertical pipe I. The tail water passes through cathode Ⅰ, anode Ⅰ, support layer Ⅰ and intelligent monitoring system Ⅰ from top to bottom; the pulse electrolysis wetland pool is also provided with a ventilation riser Ⅰ; the cathode Ⅰ and anode Ⅰ are connected through a wire Ⅰ, and the wire Ⅰ is equipped with a pulse power supply and a resistor; The difference between the voltage-stabilized vertical flow electrolysis wetland (2) and the pulsed vertical flow electrolysis wetland (1) is that the pulsed power supply is replaced by a voltage-stabilized power supply.

4. According to claim 3, a sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland is characterized in that: The cathode I and anode I filter materials of the pulse vertical flow electrolysis wetland (1) are filled with the same material, both using coconut shell activated carbon as filler and placing carbon felt-stainless steel mesh in the middle as electrode, the anode I and cathode I are respectively connected to copper wire I, and the connection of the wire submerged in the wetland filter material is first coated with conductive glue, and then coated with epoxy resin after air drying to avoid short circuit caused by direct connection between the wire and water; The cathode I and anode I in the pulse vertical flow electrolysis wetland (1) are each provided with three cathode sampling ports and three anode sampling ports; wherein the concentration of the i-th index at the three cathode sampling ports is X 1i , X 2i , X 3i ; The concentration of the i-th indicator of the three anode sampling ports is Y 1i , Y 2i , Y 3i ; then the concentration of the cathode index X t The concentration Y of the anode index i is calculated using formula (3): t Calculated using formula (4; 1≤i≤24； The concentration of the i-th index of the three cathode sampling ports II of the cathode in the steady-voltage vertical flow electrolysis wetland (2) is A 1i , A 2i , A 3i ; The concentration of the i-th index at the three anode sampling ports II is B 1i , B 2i , B 3i ; then the concentration A of the i-th index of cathode II t The concentration B of the i-th index of anode II 2-10 is obtained by formula (5): t Using formula (6) we can obtain:

5. A sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland according to claim 1 or 3, characterized in that: The primary control system (5) is an intelligent monitoring system I, which is arranged on the outlet pipe of the pulse vertical flow electrolysis wetland (1), and uses the water quality comprehensive treatment index E to judge whether the outlet water quality of the pulse vertical flow electrolysis wetland (1) meets the preliminary purification standard. The judgment method is as shown in formula (7): Note: C in , i : The i-th indicator is the influent concentration, mg / L; the first indicator is BOD, the second indicator is COD, the third indicator is SS, the fourth indicator is TN, and the fifth indicator is TP; C1, i : First-stage effluent concentration, mg / L; w i :Indicator weight coefficient (w BOD =0.25, w COD =0.20, w SS =0.20, w TN =0.15, w TP =0.20) E: comprehensive water quality treatment index; A steering valve I is also provided on the water pipe behind the intelligent monitoring system I. If the output is 1, the intelligent monitoring system I controls the steering valve I to control the tail water to flow through the return pipe I to the water reservoir behind the pulse vertical flow electrolysis wetland (1) and enter the next level of voltage-stabilized vertical flow electrolysis wetland (2) for purification; if the output is 0, the intelligent monitoring system I controls the steering valve I to control the tail water to flow into the return pipe I and enter the water reservoir in front of the pulse vertical flow electrolysis wetland (1) again to achieve circulation purification. The flow meter I is provided on the return pipe I to detect the amount of return water; The secondary control system (6) is an intelligent monitoring system II, which is arranged on the outlet pipe of the voltage-stabilized vertical flow electrolysis wetland to judge whether the outlet water quality of the voltage-stabilized vertical flow electrolysis wetland meets the surface water Class III standard and whether the greenhouse gas emissions meet the standard. The judgment method is as shown in formula (8): Note: C i :The ith indicator is the effluent concentration (mg / L) (the water quality items are sorted according to the serial number of the Class III water standard of the "Surface Water Environmental Quality Standard" (GB3838-2002), the first indicator is water temperature, the second indicator is pH, the third indicator is dissolved oxygen, ..., the 24th indicator is coliform group (individuals / L)) C i0 :Surface water standard of Class III for the i-th indicator, mg / L; C gas Average daily emission concentration of each gas, mg / m 3 ; W: comprehensive gas processing index; If the output is 1, the intelligent monitoring system II controls the tailwater to flow to the stabilization pond (4) set behind the steady-pressure vertical flow electrolysis wetland by controlling the diverter valve II on the outlet pipe; If the output is 0, the intelligent monitoring system II controls the diverter valve II on the outlet pipe to control the tail water to flow into the return pipe II and then enter the reservoir II in front of the steady-pressure vertical flow electrolysis wetland 2 for purification again; the flow meter II is set on the return pipe II to detect the return water volume Q 2回 .

6. According to claim 1, a sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland is characterized in that: The water outlets of the pulse vertical flow electrolysis wetland (1) and the voltage-stabilized vertical flow electrolysis wetland (2) are provided with photoacoustic spectroscopy greenhouse gas sensors I and waterproof measures are taken to monitor the emission of the main greenhouse gases CH4, N2O, and CO2, clarify the emission rate and change trend of greenhouse gases in the electrolysis artificial wetland under different operating conditions, and grasp the time and conditions of the peak and trough of its emission.

7. According to claim 1, a sewage plant tailwater deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland is characterized in that: The areas of the pulse vertical flow electrolysis wetland (1) and the voltage-stabilized vertical flow electrolysis wetland (2) are optimized according to the main assessment indicators (CODcr≤20mg / L, NH3-N≤1.0mg / L, TP≤0.2mg / L) in Class III water of the "Surface Water Environmental Quality Standard" (GB3838-2002). The area A1 of the pulse vertical flow electrolysis wetland (1) is expressed as formula (1), and the area A2 of the voltage-stabilized vertical flow electrolysis wetland (2) is expressed as formula (2). Q: tailwater flow, m 3 / d; HLR pulse =K p *HLR Traditional: Pulse electrolysis hydraulic load rate (K p is the electrolysis enhancement coefficient, which is 2 to 3. The HLR of traditional vertical flow wetlands is about 0.5 to 1.0 m 3 / (m 2 d)) Q: tailwater flow, m 3 / d; β: Electrolytic denitrification efficiency coefficient, 0.8~1.2g / (m 2 d)) γ: Anode phosphorus dissolution coefficient, 0.15~0.25g / (A·h) I: working current, 50~200A / m 2 .

8. A sewage plant tail water deep purification and greenhouse gas coordinated control method based on a sewage plant tail water deep purification and greenhouse gas coordinated control system based on a two-stage dynamic electrolysis vertical flow artificial wetland as described in claim 3, characterized in that: The following steps are involved: Step 1) According to the tailwater volume Q of the nearby sewage plant to be undertaken by the artificial wetland, and the main assessment indicators of Class III water in the "Surface Water Environmental Quality Standard" (GB3838-2002) (CODcr≤20mg / L, NH3-N≤1.0mg / L, TP≤0.2mg / L), the area A1 of the pulse vertical flow electrolysis wetland (1) and the area A2 of the steady-state vertical flow electrolysis wetland (2) are optimized and designed: Q: Tailwater flow (m 3 / d) HLR pulse =K p *HLR Traditional: Pulse electrolysis hydraulic load rate (K p is the electrolysis enhancement coefficient, which is 2 to 3. The HLR of traditional vertical flow wetlands is about 0.5 to 1.0 m 3 / (m 2 d)) Q: tailwater flow, m 3 / d; β: Electrolytic denitrification efficiency coefficient, 5 to 20 g / (m 2 d)) γ: Anode phosphorus dissolution coefficient, 0.15~0.25g / (A·h) I: working current, 50~200A / m 2 Step 2), the tail water of the sewage treatment plant is temporarily stored in the reservoir Ⅰ, and is pumped into the pulse vertical flow electrolysis wetland (1) through the water pump Ⅰ, the duty cycle of the pulse power supply is α, the unit is %; the frequency is β, the unit is Hz; the voltage is γ, the unit is V; the tail water enters the water distribution horizontal pipe Ⅰ and the water distribution vertical pipe Ⅰ in turn, and is evenly distributed by the spray nozzle Ⅰ, and then the tail water infiltrates into the cathode layer Ⅰ, the anode layer Ⅰ, and the supporting layer Ⅰ in turn, and then flows to the intelligent monitoring system Ⅰ, three cathode sampling ports (1-12) are opened on the cathode side, and three anode sampling ports (1-13) are opened on the anode side. Water quality data and greenhouse gas concentration are monitored, displayed, and stored by the intelligent monitoring system Ⅰ. The water quality items are sorted according to the serial number of the Class III water standard of the "Surface Water Environmental Quality Standard" (GB3838-2002). The first indicator is water temperature, the second indicator is pH, the third indicator is dissolved oxygen..., and the 24th indicator is coliform group (individuals / L). The real-time water quality of the cathode area is The real-time water quality of the anode area is Photoacoustic spectroscopy greenhouse gas sensors (5-5) are installed at three cathode sampling ports (1-12) and three anode sampling ports (1-13) to monitor the emission of three major greenhouse gases (CH4, N2O, CO2) in real time; Step 3), the intelligent monitoring system I needs to determine whether the effluent water quality of the pulse vertical flow electrolysis wetland (1) meets the preliminary purification standard. The determination method is as shown in formula (7): Note: C in , i : The influent concentration of the i-th indicator (mg / L) (the first indicator is BOD, the second indicator is COD, the third indicator is SS, the fourth indicator is TN, and the fifth indicator is TP) C1, i :First-stage effluent concentration (mg / L) w i :Indicator weight coefficient (w BOD =0.25, w COD =0.20, w SS =0.20, w TN =0.15, w TP =0.20) E: Comprehensive water quality treatment index Working condition 1: if the output is 1, the intelligent monitoring system I controls the tailwater to flow to the water storage tank II behind the pulse vertical flow electrolysis wetland (1) by controlling the steering valve I; Working condition 2: If the output is 0, the intelligent monitoring system I controls the tail water to flow into the return pipe I through the steering valve I and enter the water storage tank I in front of the pulse vertical flow electrolysis wetland (1) again. The flow meter is set on the return pipe I to detect the return water volume Q 1回 ; Step 4), the tail water that has reached the preliminary purification standard enters the reservoir II and is pumped into the steady-state vertical flow electrolysis wetland (2) through the water pump II. The real-time water quality in the cathode area is The real-time water quality of the anode area is Photoacoustic spectroscopy greenhouse gas sensor II monitors the emissions of three greenhouse gases, CH4, N2O, and CO2, from the anode and cathode sampling ports in real time; Step 5), the intelligent monitoring system (6-1) determines whether the effluent water quality of the steady-voltage vertical flow electrolysis wetland (2) meets the surface water Class III standard, and the determination method is as shown in formula (8): Note: C i :The ith indicator is the effluent concentration (mg / L) (the water quality items are sorted according to the serial number of the Class III water standard of the "Surface Water Environmental Quality Standard" (GB3838-2002), the first indicator is water temperature, the second indicator is pH, the third indicator is dissolved oxygen..., the 24th indicator is coliform group (individuals / L)) C i0 :Surface water standard of Class III for item i (mg / L) C gas Daily average emission concentration of each gas (mg / m 3 ) W: Gas comprehensive treatment index Working condition 1: If the output is 1, the intelligent monitoring system (6-1) controls the tailwater to flow to the stabilization pond (4) by controlling the steering valve (6-2); Working condition 2: If the output is 0, the intelligent monitoring system (6-1) controls the tail water to flow into the return pipe (6-4) and enter the reservoir (3-2) again by controlling the steering valve (6-2); the flow meter (6-3) is set on the return pipe (6-4) to detect the return water volume Q 2回 .

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