CN215365221U - Membrane filtration concentrate processing apparatus - Google Patents

Abstract

The utility model relates to a membrane filtration concentrate treatment device, which comprises a sewage inlet pipe, a sulfuric acid dosing tank, a ferrous sulfate dosing tank, a first pipeline mixer, a second pipeline mixer, a reaction tank, a direct-current stabilized power supply, a xenon lamp bank, an anode plate, a cathode plate and an aeration device, wherein the sewage inlet pipe is connected with the first pipeline mixer; the water inlet of the reaction tank is communicated with a sewage inlet pipe, and the anode plates and the cathode plates are vertically arranged in the reaction tank in an equidistant and alternate manner; the xenon lamp group is vertically arranged in the reaction tank and is positioned between the anode plate and the cathode plate; the bottom of the reaction tank is provided with an aeration device, the outlet of the sulfuric acid dosing tank is communicated with the first pipeline mixer, the ferrous sulfate dosing tank is communicated with the second pipeline mixer, and the outlet of the second pipeline mixer is communicated with the water inlet of the reactor. Compared with the traditional Fenton and electro-Fenton device, the device has the advantages that the treatment effect is obviously improved, the removal rate of organic pollutants is high, the purposes of reducing the content of ammonia nitrogen and decoloring are achieved, and the device is simple to operate, stable in operation and small in size.

Description

Membrane filtration concentrate processing apparatus

Technical Field

The utility model relates to a membrane filtration concentrated solution treatment device, and belongs to the technical field of sewage treatment.

Background

During the processes of collection, stacking, transportation and collection and terminal treatment of the domestic garbage, water contained in the garbage is extruded and overflows and is mixed with natural precipitation and washing water, so that toxic and harmful domestic sewage is formed, and the domestic sewage is called as garbage leachate. The landfill leachate has the characteristics of high organic pollutant concentration, complex components and large water quality change, contains various toxic and harmful inorganic matters and organic matters, and also contains non-chlorinated aromatic compounds such as naphthalene and phenanthrene, chlorinated aromatic compounds, phenolic compounds, aniline compounds and the like which are difficult to biodegrade. Compared with municipal sewage, the concentration of landfill leachate pollutants is much higher, so that leachate can not be directly discharged into a municipal sewage pipeline without strict treatment. The treatment of the landfill leachate is widely carried out by adopting a comprehensive treatment process, namely 'pretreatment, biological treatment and advanced treatment'. The advanced treatment generally adopts membrane filtration treatment technologies, including ultrafiltration, nanofiltration, reverse osmosis and the like. The ultrafiltration can filter out macromolecules and suspended substances, and the main components of the ultrafiltration membrane are water, humic acid, various micromolecules and Ca²⁺、Mg²⁺、Na⁺、Cl^-、CO₃ ^2-、SO₄ ^2-Plasma, further nanofiltration is needed for further treatment; the effluent treated by the nanofiltration membrane can basically reach the discharge standard, but the nanofiltration only plays a role of physical filtration, so that the clear liquid reaches the standard, and meanwhile, a membrane filtration concentrated solution with the volume of 20-25% is generated. Most of divalent salt and organic matters which are difficult to be biochemically degraded or not are enriched in the nanofiltration concentrated solution.

At present, typical modes for treating membrane filtration concentrated solution at home and abroad include a recharge method, a spray burning method, an evaporation method, an advanced oxidation method and the like. The core principle of advanced oxidation technologies such as Fenton method, electro-Fenton method and photo-Fenton method is that H₂O₂In Fe²⁺The hydroxyl radicals react with organic matters to effectively remove organic pollutants which cannot be degraded by the traditional biomembrane technology by the oxidative decomposition of the hydroxyl radicals and the organic matters in cooperation with other oxidants, and the organic pollutants do not have organic matter type selectivity until the organic pollutants are degraded into CO₂、H₂O and other mineral salts. The electro-Fenton process can directly produce H by an electrolytic reaction₂O₂Only adding proper amount of Fe into the reaction system²⁺Can continuously generate a large amount of OH, has simple technical realization, easy operation and low cost, and is a sewage treatment technology with great development prospect. However, the electro-Fenton reaction system of the prior art is a process of oxidative decomposition of organic contaminants, H₂O₂Is not high in the generation rate and utilization rate, and further part of Fe²⁺Will be covered with H₂O₂Is oxidized into Fe³⁺Will react with degradation intermediates (e.g. OH)^-) Form a complex to block Fe²⁺The recycling of the organic pollutants affects the yield and the generation rate of OH, thereby reducing the efficiency of degrading the organic pollutants by the electro-Fenton method. Therefore, it is necessary to develop a technique for combining the electro-fenton method with other oxidation techniques to improve the degradation efficiency of the electro-fenton method.

SUMMERY OF THE UTILITY MODEL

The utility model aims to make up for the defects of a single electro-Fenton method and provides a membrane filtration concentrated solution treatment device so as to improve the oxidation efficiency of an electro-Fenton reaction system and the removal rate of organic pollutants and improve the biodegradability of a membrane filtration concentrated solution.

Technical scheme

A membrane filtration concentrated solution treatment device comprises a sewage inlet pipe, a sulfuric acid dosing tank, a ferrous sulfate dosing tank, a first pipeline mixer, a pH online monitor, a second pipeline mixer, a reaction tank, a direct current stabilized voltage power supply, a xenon lamp bank, an anode plate, a cathode plate, an aeration device and an aeration pump;

the reaction tank is provided with a water inlet and a water outlet, the water outlet is positioned at the upper part of the side surface of the reaction tank, the water inlet is positioned at the bottom of the side surface of the reaction tank, and the water inlet is communicated with a sewage inlet pipe; the number of the anode plates and the cathode plates is more than two, the anode plates and the cathode plates are vertically arranged in the reaction tank at equal intervals, the anode plates are connected with the positive electrode of the direct current stabilized power supply, and the cathode plates are connected with the negative electrode of the direct current stabilized power supply; the xenon lamp group is vertically arranged in the reaction tank and is positioned between the anode plate and the cathode plate; the bottom of the reaction tank is provided with an aeration device, and the aeration device is connected with an aeration pump;

first pipeline mixer, pH on-line monitoring appearance, second pipeline mixer set gradually on the sewage inlet tube, and the export of sulphuric acid dosing tank passes through pipeline and measuring pump and first pipeline mixer intercommunication, and the ferrous sulfate dosing tank passes through pipeline and measuring pump and second pipeline mixer intercommunication, and the export and the reactor water inlet intercommunication of second pipeline mixer.

Furthermore, a transparent protective cover is arranged outside the xenon lamp group, so that the xenon lamp group can be protected from being corroded under the condition of not influencing the light transmittance.

Furthermore, the anode plate is made of one of a platinum electrode, a boron-doped diamond electrode, a titanium-based lead dioxide/tin dioxide/ruthenium dioxide composite electrode, an activated carbon fiber electrode or a graphite electrode.

Furthermore, the cathode plate is made of one of a graphite electrode, a platinum electrode, a stainless steel electrode or a titanium-based electrode.

Further, the distance between the adjacent anode plate and the cathode plate is 2-4 cm.

Further, the xenon lamp group is a PLS series strong light all-band light source.

The principle of membrane filtration of concentrate using the above-described device: under the irradiation of xenon lamp set, solar radiation is simulated, and oxygen molecules are electrolyzed and reduced to H on the surface of the cathode plate₂O₂，H₂O₂With Fe in the combined medicament²⁺Fenton reaction occurs to generate hydroxyl free radical OH, and OH is oxidized to degrade organic pollutants. Wherein Fe²⁺Can play a catalytic role in the reaction with H₂O₂Reaction to form Fe³⁺. Due to Fe²⁺Reduction potential of (C) is lower than that of (O)₂Is high in initial reduction potential, and thusFe³⁺The reduction reaction is preferentially carried out on the surface of the cathode plate to generate Fe²⁺The catalyst is used as a catalyst to continuously participate in Fenton reaction to form a virtuous cycle.

Fe in electro-Fenton reaction system²⁺The chemical reaction that occurs may include those represented by the following formulas (1) to (5);

a negative plate: o is₂+2H⁺+2e^-→H₂O₂ E=0.69V/NHE formula (1)

Fe²⁺+H₂O₂→Fe³⁺+·OH+OH^- k ₁ =58M^-·S^-Formula (2)

OH + RH (organic) → CO₂+H₂O + P (mineral salt) formula (3)

An anode plate: 2H₂O→O₂+4H⁺+4e^-Formula (4)

A negative plate: fe³⁺+ e^-→Fe²⁺ E=0.77V/NHE formula (5)

Cl in electro-Fenton reaction system^-The chemical reaction that occurs may include those represented by the following formula (6) to formula (10);

2Cl^-→Cl₂+2e^- formula (6)

Cl₂+H₂O → HCl + HClO formula (7)

6HClO+3H₂O→2ClO₃ ^-+4Cl^-+12H⁺+1.5O₂+2e^-Formula (8)

OCl^-+H₂O+2e^-→Cl^-+2OH^-Formula (9)

2NH₄ ⁺+3HClO→N²+3H₂O+5H⁺+3Cl^-Formula (10)

The concentrate itself containing Cl^-Generation of Cl by electrolytic reaction₂And HClO to further promote the oxidative degradation of organic substances and kill fungi and bacteriaAnd degrading metabolites secreted by microbial cells; meanwhile, ammonia nitrogen in the sewage is degraded and directly converted into harmless nitrogen, and the removal rate can reach 100 percent to the maximum; in addition, OH and Cl having strong oxidizing property₂And oxidizing agents such as HCLO (hydrogen chloride) and the like can react with chromophoric groups in the concentrated solution, so that chemical bonds of the chromophoric groups are broken or the chemical structures of the chromophoric groups are changed, and the aim of decoloring is fulfilled.

Has the advantages that: the utility model provides a membrane filtration concentrated solution treatment device, which has the following obvious effects:

(1) the treatment device synergistically couples multiple advanced oxidation technologies such as hydroxyl radical oxidation, electrolytic oxidation, hypochlorous acid oxidation, perchloric acid oxidation, electric flocculation and adsorption, xenon lamp set excitation oxidation and the like into a whole, and can achieve the purpose of removing pollutants of different types together;

(2) the ferrous sulfate agent used in the utility model is mixed with the concentrated solution for reaction in a pipeline dosing mode to provide Fe²⁺Directly and efficiently promote Fe²⁺And H₂O₂Reaction efficiency and improved Fe²⁺The cyclic utilization rate in the reaction system;

(3) the xenon lamp set is adopted to simulate solar radiation, not only visible light wave bands but also the most important ultraviolet light wave bands, and the xenon lamp set is of a full wave band type. Wherein, the visible light wave band only has the function of promoting the degradation of the colored organic pollutants through the sensitization of the colored organic pollutants, but has no promoting effect on the colorless organic pollutants. But the ultraviolet light wave band promotes the Fenton reaction from the root, and the ultraviolet light promotes and excites H in the Fenton reaction process₂O₂Generating hydroxyl radical OH, Fe (OH)₂OH and Fe may also be formed²⁺While having only a very small amount of H₂O₂Self-extinguishing occurs, and H is increased₂O₂Utilization rate;

(4) the utility model adopts the parallel design of the electrode groups, improves the adaptability and the treatment effect of the treatment device to the quality and the quantity of the domestic sewage, and can increase or decrease the parallel electrode groups according to the quantity of the treated water quantity.

(5) The treatment device has the advantages of simple operation, stable operation and small volume, avoids the difficulty of large volume of biological reaction, and is suitable for various fields with limited occupied area.

Drawings

FIG. 1 is a schematic view showing the structure of a membrane filtration concentrate treatment apparatus according to the present invention;

in the figure: 1-a sewage inlet pipe; 2-water outlet; 3-an anode plate; 4-a cathode plate; 5-a direct current stabilized power supply; 6-an aeration pump; 7-an aeration device; a group of 8-xenon lamps; 9-a transparent protective cover; 10-a reaction tank; 11-a sulfuric acid dosing tank; 12-a metering pump; 13-a first pipeline mixer; 14-online pH monitor; 15-ferrous sulfate dosing tank; 16-second line mixer.

Detailed Description

The technical solution of the present invention will be described in further detail with reference to the accompanying drawings.

Example 1

Referring to fig. 1, a membrane filtration concentrate treatment device comprises a sewage inlet pipe 1, a sulfuric acid dosing tank 11, a ferrous sulfate dosing tank 15, a first pipeline mixer 13, an online pH monitor 14, a second pipeline mixer 16, a reaction tank 10, a direct current stabilized voltage power supply 5, a xenon lamp bank 8, an anode plate 3, a cathode plate 4, an aeration device 7 and an aeration pump 6;

the reaction tank 10 is provided with a water inlet and a water outlet 2, the water outlet 2 is positioned at the upper part of the side surface of the reaction tank, the water inlet is positioned at the bottom of the side surface of the reaction tank, and the water inlet is communicated with the sewage inlet pipe 1; in the embodiment, the number of the anode plates 3 and the cathode plates 4 is two, the anode plates are made of titanium-based ruthenium iridium electrodes, the cathode plates are made of stainless steel electrodes, the anode plates and the cathode plates are vertically arranged in the reaction tank 1 in an equidistant and alternate mode, the distance between the adjacent anode plates and the adjacent cathode plates is 3cm, the anode plates are connected with the anode of the direct current stabilized voltage power supply 5, and the cathode plates are connected with the cathode of the direct current stabilized voltage power supply 5; the xenon lamp group is a PLS series strong light all-band light source, the output luminous power is 50w, the xenon lamp group 8 is vertically arranged in the reaction tank and is positioned between the anode plate 3 and the cathode plate 4, and a transparent protective cover 9 is arranged outside the xenon lamp group 8, so that the xenon lamp group can be protected from being corroded under the condition of not influencing the light transmittance; the bottom of the reaction tank 1 is provided with an aeration device 7, and the aeration device 7 is connected with an aeration pump 6;

the first pipeline mixer 13, the pH on-line monitor 14 and the second pipeline mixer 16 are sequentially arranged on the sewage inlet pipe 1, the outlet of the sulfuric acid dosing tank 11 is communicated with the first pipeline mixer 13 through a pipeline and a metering pump 12, the ferrous sulfate dosing tank 15 is communicated with the second pipeline mixer 16 through a pipeline and a metering pump, and the water inlet of the outlet reactor 1 of the second pipeline mixer 16 is communicated.

Application test:

the device of embodiment 1 is adopted to treat the membrane filtration concentrated solution, the membrane filtration concentrated solution adopted in the experiment is the concentrated solution of a concentrated solution collecting tank of a certain landfill in Shenzhen city, the landfill leachate adopts a combined process of pretreatment, UASB, multistage A/O, MBR membrane system, NF and RO, and the treated effluent water can reach the discharge standard of table 2 of the pollution control Standard for landfill of domestic waste GB 16889-2008. Wherein, the membrane filtration concentrated solution generated by the Reverse Osmosis (RO) system returns to the front end of the Nanofiltration (NF) system for continuous filtration treatment; and the membrane filtration concentrated solution generated by a Nanofiltration (NF) system is discharged into a concentrated solution collecting tank for recharging treatment. Through water quality testing, the membrane filtration concentrate adopted in the experiment is tan, and the water quality analysis result is as follows: COD =1223mg/L, BOD =128mg/L, ammonia nitrogen =120mg/L, chroma =303, B/C =0.10, and is not suitable for continuous treatment by biological methods due to poor biodegradability.

The membrane filtration concentrate was treated using the apparatus of example 1, as follows:

(1) the concentrated solution continuously passes through the water inlet pipe 1 at a certain flow rate, and the hydraulic retention time is controlled to be 5 hours; fully mixing the concentrated solution and the sulfuric acid solution in a first pipeline mixer 13, and monitoring the pH value of the pipeline solution in real time by a pH online monitor 14 to control the pH value of the mixed solution to be 2.8-3.2; then mixing the mixture with a ferrous sulfate solution in a second pipeline mixer 16, and entering a reaction tank 10 for electrolytic catalytic oxidation treatment;

(2) turning on an aeration pump 6, aerating the liquid in the reaction tank 10 through an aeration device 7 to promote gas phase diffusion and medicament dispersion, wherein the air flow rate is 200 mL/min;

(3) the DC stabilized voltage supply 5 is turned on, and the current density of the reaction tank 10 is made to be 50mA/cm by adjusting the voltage intensity²Meanwhile, the xenon lamp group 8 is switched on, and the output optical power is 50W;

(4) the reaction tank generates photochemical reaction, electrochemical reaction, electro-Fenton reaction, heterogeneous electro-Fenton reaction, electro-flocculation and adsorption precipitation reaction under the simulated solar radiation of the xenon lamp bank, and macromolecular long-chain organic matters are decomposed into micromolecular chain-broken organic matters and even directly into CO₂And H₂O, thereby efficiently reducing the organic matter concentration of the concentrated solution in the reaction tank, wherein the electro-Fenton treatment time is 5h, and the supernatant after the electrolysis treatment is discharged from the water outlet 2.

(5) The detection and analysis of the supernatant discharged from the water outlet 2 are carried out, and the results are as follows:

as can be seen from the detection results of the effluent quality of the embodiment, the device disclosed by the utility model has a good effect on the treatment of the concentrated solution, the removal rates of COD, BOD, ammonia nitrogen and chromaticity are respectively 82.4%, 39.9%, 85.6% and 87.5%, the B/C ratio is obviously improved from 0.1 to 0.36, and the biodegradability is obviously improved.

The technical idea and the technical features of the present invention are described above, but the scope of the present invention is not limited to the specific details of the above embodiments. All equivalent changes or modifications made according to the spirit of the present invention are within the scope of the present invention.

Claims (6)

1. A membrane filtration concentrated solution treatment device is characterized by comprising a sewage inlet pipe (1), a sulfuric acid dosing tank (11), a ferrous sulfate dosing tank (15), a first pipeline mixer (13), a pH on-line monitor (14), a second pipeline mixer (16), a reaction tank (10), a direct current stabilized voltage power supply (5), a xenon lamp set (8), an anode plate (3), a cathode plate (4), an aeration device (7) and an aeration pump (6);

the reaction tank (10) is provided with a water inlet and a water outlet, the water outlet (2) is positioned at the upper part of the side surface of the reaction tank, the water inlet is positioned at the bottom of the side surface of the reaction tank, and the water inlet is communicated with the sewage inlet pipe (1); the number of the anode plates (3) and the number of the cathode plates (4) are more than two, the anode plates (3) and the cathode plates (4) are vertically arranged in the reaction tank (10) in an equidistant and alternate mode, the anode plates (3) are connected with the positive electrode of the direct current stabilized voltage power supply (5), and the cathode plates (4) are connected with the negative electrode of the direct current stabilized voltage power supply (5); the xenon lamp group (8) is vertically arranged in the reaction tank (10) and is positioned between the anode plate (3) and the cathode plate (4); an aeration device (7) is arranged at the bottom of the reaction tank (10), and the aeration device (7) is connected with an aeration pump (6);

first pipeline mixer (13), pH on-line monitoring appearance (14), second pipeline mixer (16) set gradually on sewage inlet tube (1), and the export of sulphuric acid dosing tank (11) passes through pipeline and measuring pump (12) and first pipeline mixer (13) intercommunication, and ferrous sulfate dosing tank (15) passes through pipeline and measuring pump and second pipeline mixer (16) intercommunication, the export and reaction tank (10) water inlet intercommunication of second pipeline mixer (16).

2. The membrane filtration concentrate treatment device of claim 1, wherein a transparent protective cover (9) is provided outside the hernia light set (8).

3. The membrane filtration concentrate treatment device of claim 1, wherein the anode plate is made of one of a platinum electrode, a boron-doped diamond electrode, a titanium-based lead dioxide/tin dioxide/ruthenium dioxide composite electrode, an activated carbon fiber electrode, or a graphite electrode.

4. The membrane filtration concentrate treatment apparatus of claim 1, wherein the cathode plate is made of one of graphite, platinum, stainless steel, or titanium-based.

5. The membrane filtration concentrate treatment device of claim 1, wherein the distance between adjacent anode and cathode plates is 2-4 cm.

6. The membrane filtration concentrate treatment apparatus of any one of claims 1 to 5, wherein the xenon lamp set is a high light full-band light source of PLS series.

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