Full-quantitative treatment method for high-end leachate membrane landfill leachate

Abstract

The invention discloses a high-end leachate membrane landfill leachate full-quantitative treatment method, and belongs to the technical field of leachate full-quantitative treatment.The high-end leachate membrane landfill leachate full-quantitative treatment method comprises the following steps of S1, pretreatment, S2, HMBR treatment, S3, electrochemical catalytic oxidation, S4, NF-RO separation and S5, control system integration. The core-shell structure of the magnetic nano flocculant can synchronously adsorb heavy metals and organic matters, the sedimentation time is shortened by the magnetic response characteristic, and the subsequent treatment load is reduced; the cross-flow filtration design of the ceramic membrane is high in anti-pollution capacity, frequent cleaning is not needed, the agent consumption and maintenance cost of the pretreatment unit are reduced, and the system stability is improved.

Description

[0001] The present invention relates to the technical field of full - quantification treatment of leachate, and more specifically, to a high - end leachate membrane full - quantification treatment method for landfill leachate. Background Art

[0002] Full - quantification treatment of landfill leachate refers to a treatment method that degrades organic matters, heavy metals, and other pollutants in landfill leachate until it meets the discharge standards. The purpose of full - quantification treatment is to ensure that all pollutants in landfill leachate are effectively removed and meet the discharge standards;

[0003] In the prior art, the patent document with the authorization announcement number CN116282638A published "A Full - Quantification Treatment Method for Landfill Leachate", which includes the following steps: S1, concentrating the landfill leachate into a regulating tank; S2, sending the landfill leachate regulated by the regulating tank into a pretreatment unit for air flotation, filtration, or coagulation sedimentation treatment to remove particulate matters in the landfill leachate; S3, sending the pretreated landfill leachate into a primary biochemical unit for biochemical treatment; S4, sending the landfill leachate biochemically treated by the primary biochemical unit into a membrane bioreactor for solid - liquid separation; S5, sending the liquid landfill leachate separated after step S4 into an air flotation unit for air flotation treatment to separate fine particle adhesives in the landfill leachate; S6, sending the landfill leachate after air flotation treatment into a micro - electrolysis ozone oxidation coupling system for iron - carbon micro - electrolysis and ozone coupling treatment;

[0004] Although the prior art reduces the sewage treatment cost, ensures that the concentrated water of the wastewater generated during the treatment process does not undergo back - irrigation, and solves the problems of pollutant and salt accumulation, the pretreatment depends on iron salts / poly - iron salts flocculation, with a large dosage of chemicals and high cost, and limited adsorption capacity for complex colloids and heavy metals; the micro - electrolysis ozone oxidation coupling system has high energy consumption and chemical agent costs, and the iron - carbon filler is prone to passivation; it does not involve the NF - RO closed - loop system, the concentrated water reflux mechanism is not clear, which may lead to pollutant accumulation; and there is a lack of on - line monitoring and intelligent regulation, making it difficult to ensure the stability of the treatment effect. Summary of the Invention

[0005] The present invention mainly provides a high - end leachate membrane full - quantification treatment method for landfill leachate, which can solve the problems of low pretreatment efficiency, high oxidation energy consumption, incomplete concentrated water treatment, and unstable treatment effect proposed in the above - mentioned background art.

[0006] To achieve the above object, the present invention provides the following technical solution: A high - end leachate membrane full - quantification treatment method for landfill leachate, including:

[0007] The leachate first enters the equalization tank for homogenization and then enters the pretreatment stage. A magnetic nano-flocculant is added and separated by a magnetic field. Then, it is filtered by a ceramic membrane to remove suspended solids and colloids. The pretreated effluent flows into a fouling-resistant composite membrane bioreactor. Through the alternating operation of anaerobic and aerobic processes, the composite membrane intercepts microorganisms to simultaneously degrade COD and ammonia nitrogen. The effluent from the HMBR enters a three-dimensional electrode-ozone synergistic oxidation system. After pH adjustment, pulsed current is used to stimulate the catalyst to generate free radicals, and ozone micro-bubbles are coupled for aeration to deeply degrade refractory organic matter. The oxidized effluent enters a nanofiltration-reverse osmosis closed-loop membrane system. First, nanofiltration is used to separate low-molecular-weight organic matter and divalent salts, and the produced water is then desalted by reverse osmosis. The concentrated water is refluxed to the equalization tank for cyclic treatment. Throughout the process, an online monitoring instrument is linked with the PLC control system to adjust the dosing amount of the flocculant and the current intensity parameters in real time. The data is synchronized to the cloud for remote operation and maintenance, ultimately achieving the full quantification treatment and efficient resource utilization of landfill leachate.

[0008] Furthermore, the magnetic nano-flocculant has a core-shell structure. The core is Fe3O4, and the shell layer is a poly-dopamine-chitosan graft-modified layer, which realizes rapid flocculation separation through magnetic responsiveness and adsorbs heavy metals and organic matter.

[0009] Furthermore, in the fouling-resistant composite membrane bioreactor, the composite membrane uses a polyvinylidene fluoride-carbon nanotube substrate, and a hydrophilic -COOH group is grafted on the surface.

[0010] Furthermore, in the three-dimensional electrode-ozone synergistic oxidation system, the three-dimensional electrode is an electrode group filled with graphene-supported TiO2 catalyst. Under the stimulation of pulsed current, the catalyst is coupled with ozone micro-bubbles to generate ·OH free radicals. The voltage of the pulsed current is 5 - 10V, and the frequency is 50Hz.

[0011] Furthermore, in the NF-RO closed-loop membrane system, the nanofiltration membrane has a spiral wound structure, and the salt rejection rate is >80%. The reverse osmosis membrane uses a disk-type reverse osmosis membrane, and the total system recovery rate is >98%. After 3 - 5 times of cyclic treatment of the concentrated water, zero discharge is achieved, and the salt substances can be resourcefully recovered after enrichment.

[0012] Furthermore, in the pretreatment stage, the membrane pore size of the ceramic membrane filtration unit is 0.1μm - 0.5μm, and it operates in a cross-flow filtration mode with a cross-flow rate of 1 - 2m / s.

[0013] Furthermore, the HMBR adopts an alternating anaerobic-aerobic operation mode, and the anaerobic-aerobic time ratio is 1:2.

[0014] The beneficial effects of the method for fully quantifying the treatment of high-end leachate membrane landfill leachate of the present invention are as follows:

[0015] Through the synergistic effect of magnetic nano-flocculants and ceramic membranes, replacing the traditional air flotation / coagulation process to achieve efficient solid-liquid separation. The core-shell structure of magnetic nano-flocculants can simultaneously adsorb heavy metals and organic substances, and the magnetic response characteristics shorten the sedimentation time and reduce the subsequent treatment load. The cross-flow filtration design of ceramic membranes has strong anti-pollution ability, does not require frequent cleaning, reduces the chemical consumption and maintenance costs of the pretreatment unit, and improves the system stability.

[0016] By integrating pollution-resistant composite membranes, three-dimensional electrode-ozone synergistic oxidation, and NF-RO closed-loop systems, problems such as membrane pollution, high energy consumption, and concentrated water are solved. The hydrophilic modification layer of the composite membrane reduces protein adsorption and extends the membrane life. The three-dimensional electrode stimulates the catalyst to generate active free radicals, enhances the efficiency of organic matter degradation, and reduces the ozone dosage. The NF-RO closed-loop system realizes the recycling treatment of concentrated water, prevents the accumulation of pollutants, and is equipped with an intelligent control system to adjust parameters in real time to ensure the efficient operation of the entire process, ultimately achieving the full quantification treatment and resource recycling of landfill leachate. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described in detail below with reference to the drawings and specific implementation methods.

[0018] Figure 1 It is a process flow schematic diagram of a high-end leachate membrane full quantification treatment method for landfill leachate of the present invention;

[0019] Figure 2 It is a method flow schematic diagram of a high-end leachate membrane full quantification treatment method for landfill leachate of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] To make the technical solutions of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0021] Example 1

[0022] As Figure 1 - Figure 2 shown, a technical solution is provided: a high-end leachate membrane full quantification treatment method for landfill leachate, including: [[ID=3l]]

[0023] Step 1. Pretreatment:

[0024] The leachate first enters the regulating tank (equipped with a stirrer to ensure uniform water quality) for homogenization adjustment of water quality and quantity. Then, a magnetic nano-flocculant (with an Fe3O4 core and a polydopamine-chitosan graft-modified layer as the shell) is added. Subsequently, through the strong magnetic field environment generated by the magnetic separation device, the flocs with magnetic cores rapidly migrate and are intercepted directionally. At the same time, by utilizing the chelation of polyphenol groups of polydopamine in the shell with heavy metal ions and the adsorption characteristics of the amino groups of chitosan with organic matter, the efficient removal of heavy metals (such as Cu2+ and Pb2+) and colloidal organic matter (such as humic acid) is achieved. This flocculant shortens the sedimentation time of the traditional flocculation process from 2 - 4 hours to within 30 minutes through magnetic responsiveness, and the dosage of the agent is only 1 / 5 - 1 / 3 of that of traditional iron salts, avoiding the generation of a large amount of chemical sludge.

[0025] Subsequently, the wastewater enters the ceramic membrane filtration unit (using α-Al2O3 ceramic membranes with pore sizes of 0.1 - 0.5 μm, and the cross-flow rate is controlled at 1 - 2 m / s). Through the cross-flow filtration mode (the feed liquid flows parallel to the membrane surface), the deposition of suspended solids on the membrane surface is reduced. By using the membrane pore sieving effect, particles, colloids, and microorganisms with particle sizes larger than 0.1 μm are further removed. Compared with traditional organic ultrafiltration membranes, the ceramic membrane has strong chemical stability, and its anti-pollution ability is increased by 3 times. The cleaning cycle can be extended from once a day to once every 15 days, and the removal rate of turbidity is stably above 99%, providing water quality guarantee for the subsequent biochemical unit.

[0026] The mechanism of the directional migration and interception of the flocs is as follows: The core of the magnetic nano-flocculant is Fe3O4 magnetic particles, and there are a large number of unpaired electrons in its crystal structure, endowing the material with strong paramagnetism. When added to the regulating tank, the Fe3O4 core collides and adsorbs with suspended particles in water (such as clay and metal hydroxides) through van der Waals forces. At the same time, the polymer chains of the polydopamine-chitosan shell crosslink with the particles through charge neutralization (the amino groups of chitosan are positively charged and neutralize the negatively charged colloids in water), forming magnetic flocs. At this time, the magnetic separation device (such as an electromagnetic coil) generates a gradient magnetic field. Due to the coupling of the magnetic moment of the internal Fe3O4 particles of the magnetic flocs with the magnetic field direction, the magnetic flocs are subjected to magnetic attraction and migrate directionally to the region with a high magnetic field intensity, and are finally intercepted on the adsorption plate or filter screen of the magnetic field device. The force formula is shown as follows:

[0027]

[0028] where μ0 is the vacuum magnetic permeability, X is the magnetic susceptibility of the flocs, V is the volume, is the magnetic field gradient;

[0029] The reason why chitosan has the characteristics of amino group and organic matter adsorption is that chitosan (polyglucosamine) is a natural polymer with rich amino (-NH2) and hydroxyl (-OH) functional groups in its molecular structure, which gives it multiple adsorption capabilities: in terms of heavy metal chelation, amino groups are protonated under neutral or acidic conditions to form -NH3 + , can adsorb negatively charged anions (such as Cr2O7 2- ), while the N and O atoms in the amino and hydroxyl groups act as electron donors and can react with Cu 2 +、Pb 2 + and other heavy metal cations to form coordination bonds to generate stable five-membered or six-membered ring chelates. Studies have shown that it has a strong 2 The saturated adsorption capacity of chitosan can reach 200-300 mg / g, which is 5-10 times higher than that of iron salts in the prior art. In terms of organic matter adsorption, the hydroxyl groups on the molecular chain adsorb polar organic matter such as phenols and carboxylic acids through hydrogen bonding, while the non-polar chain segments capture non-polar organic matter such as benzene series through hydrophobic action. For colloidal humic acid, its amino group can neutralize the negative charge of the humic acid carboxylic acid group, promote coagulation through electrical neutralization and bridging, and the removal rate can reach more than 85%. In addition, chitosan is biocompatible and can be degraded by microorganisms into harmless glucosamine.

[0030] Step 2: HMBR treatment:

[0031] The effluent after pretreatment flows into the pollution-resistant composite membrane bioreactor (HMBR), and adopts the anaerobic-aerobic alternating operation mode (anaerobic-aerobic time ratio is 1:2), and realizes the efficient coordination of "phosphorus release-phosphorus absorption" and "denitrification-nitrification" through timing control. The polyvinylidene fluoride (PVDF)-carbon nanotube composite membrane filled in the reactor is based on PVDF, and the uniformly dispersed carbon nanotubes form a three-dimensional conductive grid to improve the mechanical strength of the membrane. At the same time, the hydrophilic -COOH groups (density of 5-8μmol / m 2 ), which reduces the water contact angle on the membrane surface from 85° to 40°, significantly reducing the adsorption and deposition of pollutants such as protein and grease, and improving the anti-pollution ability by 40%;

[0032] The composite membrane module realizes solid-liquid separation through cross-flow filtration (membrane surface flow velocity 0.1 - 0.3 m / s), and at the same time provides an attachment carrier for microorganisms to form a biofilm with a thickness of about 200 - 300 μm. In the anaerobic stage (accounting for 1 / 3 of the cycle), facultative bacteria use the organic matter in the wastewater to reduce nitrate to nitrogen gas (denitrification), and at the same time release phosphorus elements; entering the aerobic stage (accounting for 2 / 3 of the cycle), aerobic bacteria oxidize ammonia nitrogen to nitrate through nitrification, and at the same time absorb phosphorus elements in excess, realizing the synchronous and efficient degradation of COD (removal rate 80% - 85%) and ammonia nitrogen (removal rate > 95%). Due to the hydrolysis and acidification of complex organic matter in the anaerobic stage, macromolecular organic matter (such as cellulose, fat) in the wastewater can be decomposed into small molecule fatty acids, improving the biodegradability of the wastewater, increasing the sludge load in the aerobic stage from 0.2 kgCOD / (kgMLSS·d) to 0.35 kgCOD / (kgMLSS·d), without the need to add additional carbon sources such as methanol, reducing the operating cost;

[0033] Among them, the anaerobic-aerobic alternating operation mode divides the reaction cycle into an anaerobic stage (accounting for a ratio of 1 / 3) and an aerobic stage (accounting for a ratio of 2 / 3) through timing control, and uses the metabolic characteristics of microorganisms under different redox conditions to achieve efficient nitrogen and phosphorus removal. In the anaerobic stage, facultative anaerobic bacteria dominate the metabolism, hydrolyzing macromolecular organic matter (such as cellulose, fat) in the wastewater into small molecule fatty acids (such as acetic acid, propionic acid), and at the same time converting nitrate nitrogen into nitrogen gas and releasing it through denitrification, realizing the dual functions of "carbon source regeneration" and "denitrification"; after entering the aerobic stage, aerobic bacteria use the small molecule substrates produced in the anaerobic stage for nitrification, oxidizing ammonia nitrogen to nitrate, and at the same time removing phosphorus elements through the excessive phosphorus absorption of polyphosphate bacteria.

[0034] Step 3, Electrochemical catalytic oxidation:

[0035] The effluent of HMBR enters the three-dimensional electrode-ozone synergistic oxidation system. First, the pH is adjusted to 3 - 4 by adding dilute sulfuric acid (the acidic environment can enhance the free radical generation efficiency), and then it flows into the three-dimensional electrode reactor filled with graphene-supported TiO2 catalyst. The reactor uses a titanium plate as the anode and a stainless steel plate as the cathode. The filled catalyst particles (particle size 2 - 3 mm) are excited by a pulsed current (voltage 5 - 10 V, frequency 50 Hz) to form a "micro electrolytic cell" effect: the high conductivity of graphene constructs an electron transport network, and TiO2 generates electron-hole pairs under the action of the pulsed electric field (TiO2 → e - +h + ), the electron reacts with dissolved oxygen in the water to generate superoxide anion radicals (O2 + e - → O2), and the hole reacts with water molecules to generate hydroxyl radicals (h + + H2O → OH + H +) Meanwhile, ozone microbubbles (bubble diameter < 100 μm) are introduced through a microporous aeration device. Ozone molecules decompose under the action of the catalyst surface and free radicals to generate more ·OH (O3 + ·OH → O2 + H2O + ·OH), forming a triple free radical generation mechanism of "electric field excitation + catalyst synergy + ozone decomposition".

[0036] For refractory organic matters such as humic acid, ·OH free radicals mineralize them into CO2 and H2O through ring-opening and chain-breaking reactions, which is 2 - 3 orders of magnitude higher than that of simple ozone oxidation. Fe 2 +, Mn 2 + and other metal ions (from catalyst dissolution or pretreatment residues) further catalyze the decomposition of ozone, increasing the ozone utilization rate from 50% in traditional processes to 85%, reducing the ozone dosage per unit treatment from 1000 ppm to 300 - 500 ppm, and reducing the energy consumption from 4 - 6 kWh / m 3 to 2.8 - 4.2 kWh / m 3 . In addition, the intermittent power supply mode of pulsed current (conducting for 10 s and disconnecting for 5 s) can reduce the electrode polarization phenomenon, extend the service life of the catalyst to 3 - 5 years, and avoid the problems of easy passivation and frequent replacement of traditional iron-carbon microelectrolysis fillers.

[0037] Step 4, NF-RO separation:

[0038] The oxidized effluent first enters the spiral wound nanofiltration membrane (NF) unit. The membrane element is made of aromatic polyamide composite material, with a molecular weight cut-off of 200 - 1000 Da and a negatively charged group (such as sulfonic acid group) on the surface. It separates low-molecular-weight organic matters (such as small molecule carboxylic acids, pesticide residues) and divalent salts (such as Ca 2+ , SO4 2- ) through charge repulsion effect and sieving action. Under the operating pressure of 0.5 - 1.0 MPa, the NF membrane has a COD removal rate of 60% - 70% and a hardness (calculated as CaCO3) rejection rate > 85%. The effluent TOC is reduced to 20 - 30 mg / L, providing pretreatment guarantee for the RO membrane.

[0039] Subsequently, the NF-produced water enters the disk tube reverse osmosis membrane (DT-RO) unit. This membrane adopts a spacer disk structure with a wide membrane sheet spacing (6 - 8 mm), can tolerate a high suspended solid concentration (SDI < 5), and achieves deep desalination through selective osmosis under a pressure of 1.5 - 2.5 MPa. The rejection rate of monovalent salts (such as NaCl) is > 99%, the conductivity of the produced water is < 100 μS / cm, and the concentrated water produced (with a salt concentration of up to 5000 - 10000 mg / L) is returned to the regulation tank through a high-pressure pump, mixed with the raw water, and undergoes 3 - 5 cycles of treatment. The dilution effect of the concentrated water is utilized to avoid concentration polarization on the membrane surface. Finally, the total water recovery rate > 98% is achieved, and only < 2% of the extremely concentrated liquid (salt > 20000 mg / L) is produced, which can recover industrial salts (such as NaCl, K2SO4) through evaporation crystallization, eliminating the discharge of concentrated water;

[0040] The reason why the dilution effect of the concentrated water avoids concentration polarization on the membrane surface is that after the concentrated water is returned to the regulation tank and mixed with the original leachate to form "diluted raw water", its salt concentration is increased by 1.5 - 2 times compared with the original water (for example, if the original water TDS is 5000 mg / L, it can reach 7500 - 10000 mg / L after mixing). However, compared with the concentrated water directly entering the RO membrane (with a salt content of 5000 - 10000 mg / L), the overall ion concentration gradient of the mixed solution is reduced. When the diluted raw water enters the NF-RO system again, the concentration difference between the membrane surface and the bulk solution is reduced, thereby weakening the concentration polarization phenomenon (that is, the phenomenon that the solute concentration on the membrane surface is higher than that of the bulk solution). The specific mechanism is as follows:

[0041] Concentration gradient control: Concentration polarization will cause the osmotic pressure on the membrane surface to increase, forcing the osmotic resistance of water molecules to increase, and at the same time exacerbating the deposition of solutes (such as salts and organic matters) on the membrane surface. Through the dilution of the concentrated water, the solute concentration in the membrane feed water is reduced, so that the concentration difference between the membrane surface and the bulk solution is reduced from 30% - 50% in the traditional process to 10% - 15%, the increase in the osmotic pressure on the membrane surface is reduced, and a stable water production flux is maintained (the decrease is < 5%);

[0042] Hydrodynamics optimization: After the recycled concentrated water is mixed with the raw water, the ionic strength in the system increases, which may promote the destabilization of colloidal particles (such as by compressing the electrical double layer), making it easier to be removed by magnetic flocculants in the pretreatment stage, reducing the colloidal pollutants (such as humic acid colloid) entering the RO membrane, and further reducing the impact of concentration polarization on the membrane performance;

[0043] Circulation times control: After the concentrated water is recycled 3 - 5 times, the salt content of the extremely concentrated liquid > 20000 mg / L. At this time, through evaporation crystallization treatment, the excessive accumulation of ions caused by long-term circulation (such as exceeding the membrane tolerance limit of 30000 mg / L) is avoided, ensuring the stability of the entire closed-loop system.

[0044] Step 5, Control system integration:

[0045] Through on-line monitoring instruments (including COD sensors, ammonia nitrogen detectors, and membrane differential pressure transmitters), key process parameters are collected in real time. The data is transmitted to the PLC control system (programmable logic controller) via the 485 communication protocol. The operating parameters of each unit are adjusted through a preset PID control algorithm (proportional-integral-derivative):

[0046] Pretreatment section: The dosage of magnetic nano-flocculant is dynamically adjusted according to the influent COD value (detection accuracy ±5mg / L). When COD > 8000mg / L, the dosage is automatically increased by 10%-20% to avoid incomplete flocculation caused by water quality fluctuations;

[0047] Electrochemical oxidation section: The acidity and alkalinity of the wastewater are monitored by an on-line pH meter (accuracy ±0.1). When pH > 4, the acid addition pump is automatically started to adjust it to the optimal reaction range of 3-4. At the same time, the pulse current intensity (adjustable from 5-10V) and ozone flow rate (0-500g / h) are adjusted according to the on-line TOC monitoring data (accuracy ±2mg / L) to achieve dynamic matching of "water quality - energy consumption";

[0048] Membrane system section: The membrane differential pressure transmitter (accuracy ±0.005MPa) monitors the pressure of the NF-RO membrane module in real time. When the differential pressure > 0.1MPa, the chemical cleaning program (CIP) is automatically triggered. The cleaning pump is controlled by the PLC to inject citric acid solution (pH 2-3) and sodium hypochlorite solution (concentration 200-400ppm) in sequence. The cleaning duration is automatically adjusted according to the degree of pollution (1-4 hours). The cleaning waste liquid is discharged from the device through a special pipeline. After the cleaning is completed, the data is synchronized to the cloud platform to generate a membrane performance trend curve (such as flux decay rate, desalination rate change, etc.), which supports remote diagnosis by staff (such as real-time warning on mobile APP, historical data traceability);

[0049] The specific implementation process of the PID control algorithm is as follows:

[0050] The proportion is for rapid response to deviation. It directly calculates the control quantity based on the deviation between the current measured value and the set value to reduce the deviation. The specific formula is as follows:

[0051] P(t) = K p ·e(t)

[0052] Where K p is the proportionality coefficient;

[0053] The integral is to eliminate the static error. It eliminates the system static error through cumulative historical deviation through integral operation to ensure that the final output value is consistent with the set value. The specific formula is as follows:

[0054]

[0055] Where Ki is the integral coefficient;

[0056] Differentiation is to suppress overshoot and oscillation. It predicts the trend based on the rate of change of the deviation, adjusts the control quantity in advance, and suppresses the overshoot or oscillation of the system. The specific formula is as follows:

[0057]

[0058] where K d is the differential coefficient.

[0059] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent for the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention shall be subject to the appended claims.

Claims

1. A full-quantification treatment method for high-end leachate membrane landfill leachate, characterized in that: The leachate first enters the regulating tank for homogenization, then enters the pretreatment process, magnetic nano-flocculant is added and separated by a magnetic field, and then filtered by a ceramic membrane to remove suspended solids and colloids; the pretreated effluent flows into a fouling-resistant composite membrane bioreactor, and through anaerobic-aerobic alternating operation, the composite membrane intercepts microorganisms to synchronously degrade COD and ammonia nitrogen; the HMBR effluent enters the three-dimensional electrode-ozone synergistic oxidation system, after pH adjustment, pulsed current is used to stimulate the catalyst to generate free radicals, and ozone microbubble aeration is coupled to deeply degrade refractory organic matter; the oxidized effluent enters the nanofiltration-reverse osmosis closed-loop membrane system, first nanofiltration is used to separate low-molecular organic matter and divalent salts, the produced water is then desalted by reverse osmosis, and the concentrated water is refluxed to the regulating tank for cyclic treatment; throughout the process, it is linked with on-line monitoring instruments and PLC control systems, the dosing amount of the flocculant and the current intensity parameters are adjusted in real time, and the data is synchronized to the cloud for remote operation and maintenance, and finally full-quantification treatment of landfill leachate and efficient resource utilization are achieved.

2. The full-quantification treatment method for high-end leachate membrane landfill leachate according to claim 1, wherein: The magnetic nano-flocculant has a core-shell structure, the core is Fe3O4, and the shell layer is a polydopamine-chitosan graft-modified layer, which realizes rapid flocculation separation through magnetic responsiveness and adsorbs heavy metals and organic matter.

3. A full-quantification treatment method for high-end leachate membrane landfill leachate according to claim 1, characterized in that: In the fouling-resistant composite membrane bioreactor, the composite membrane uses a polyvinylidene fluoride-carbon nanotube substrate, and a hydrophilic -COOH group is grafted on the surface.

4. A full - quantification treatment method for high - end leachate membrane landfill leachate, as claimed in claim 1, wherein: In the three-dimensional electrode-ozone synergistic oxidation system, the three-dimensional electrode is an electrode group filled with graphene-loaded TiO2 catalyst. Under the excitation of pulsed current, the catalyst is coupled with ozone microbubbles to generate ·OH free radicals. The pulsed current voltage is 5-10V and the frequency is 50Hz.

5. The full-quantification treatment method for high-end leachate membrane landfill leachate according to claim 1, characterized in that: In the NF-RO closed-loop membrane system, the nanofiltration membrane has a spiral wound structure, the salt rejection rate > 80%, the reverse osmosis membrane uses a disk-type reverse osmosis membrane, the total system recovery rate > 98%, the concentrated water is treated by 3-5 cycles to achieve zero discharge, and the salt substances can be recycled resourcefully after enrichment.

6. A full-quantification treatment method for high-end leachate membrane landfill leachate according to claim 1, characterized in that: In the pretreatment process, the membrane pore size of the ceramic membrane filtration unit is 0.1μm - 0.5μm, and it operates in a cross-flow filtration mode, and the cross-flow rate is 1-2m / s.

7. A full - quantification treatment method for high - end leachate membrane landfill leachate, according to claim 1, characterized in that: The HMBR adopts an anaerobic-aerobic alternating operation mode, and the anaerobic-aerobic time ratio is 1:2.

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