Wastewater treatment device coupling micro-electrolysis with fenton

Abstract

The present application relates to a kind of micro-electrolysis coupling fenton's wastewater treatment device, comprising: micro-electrolysis reaction bin, internal cavity is divided into the first mixing zone for mixing wastewater and neutralizing liquid, micro-electrolysis filler area for micro-electrolysis of wastewater and first clear water zone for collecting post-processing wastewater from below to above;First clear water zone and first mixing zone are communicated by pipeline, and the pipeline is installed with the first circulating pump for driving water flow to flow from below to above;Fenton reaction bin, internal cavity is divided into the second mixing zone for mixing wastewater and reaction liquid, second clear water zone for collecting post-processing wastewater from below to above;The water inlet of second mixing zone is communicated by pipeline with the overflow port of first clear water zone.The above-mentioned micro-electrolysis coupling fenton's wastewater treatment device can generate ferrous ions by adjusting the wastewater residence time in micro-electrolysis reaction bin, micro-electrolysis reaction bin inlet pH and other methods, reduce the amount of reagent addition, and the wastewater treatment effect is better.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wastewater treatment, in particular to a micro-electrolysis coupled with Fenton wastewater treatment device. BACKGROUND

[0002] Compared with general wastewater, high-concentration refractory organic wastewater has the characteristics of high toxicity, long-term persistence and biological accumulation. The biochemical treatment method is widely used in industrial wastewater treatment due to its economy and effectiveness. However, due to the characteristics of high-concentration refractory wastewater, such as containing benzene amine, heterocyclic compounds and high salt, high organic content, low B / C value and strong biological toxicity, the traditional biochemical method for treating such wastewater has the problems of long treatment period, poor effect, high cost of deep treatment and difficulty in meeting the discharge standard. At present, the physical and chemical treatment methods include coagulation sedimentation, adsorption, Fenton oxidation, micro-electrolysis, ozone oxidation, photocatalysis and ultrasonic method. The Fenton oxidation method has good effect on removing organic matter in wastewater and improving the B / C value of wastewater, but it has the problems of high requirement for control of reagent addition amount, large reagent addition amount and large sludge production. The micro-electrolysis method can improve the B / C value of wastewater, change the form of organic matter in wastewater and be beneficial to subsequent wastewater treatment, but it has limited removal capacity for organic matter. Therefore, it is difficult to achieve the treatment index of high-concentration refractory wastewater by using a single technical means, and simple combination cannot achieve the best wastewater treatment effect. SUMMARY

[0003] Therefore, it is necessary to provide a micro-electrolysis coupled with Fenton wastewater treatment device with strong relevance and good wastewater treatment effect in view of the above technical problems.

[0004] A micro-electrolysis coupled with Fenton wastewater treatment device comprises:

[0005] A micro-electrolysis reaction bin, the internal cavity of which is divided into a first mixing area for mixing wastewater and neutralizing liquid, a micro-electrolysis filler area for micro-electrolysis of wastewater and a first clear water area for collecting treated wastewater from bottom to top; the first clear water area and the first mixing area are connected by a pipeline, and a first circulating pump for driving water flow from bottom to top is installed on the pipeline; and

[0006] A Fenton reaction bin, the internal cavity of which is divided into a second mixing area for mixing wastewater and reaction liquid and a second clear water area for collecting treated wastewater from bottom to top; the water inlet of the second mixing area is connected with the overflow outlet of the first clear water area by a pipeline.

[0007] Further, the wastewater treatment device further comprises a membrane filtration bin, an inner cavity of the membrane filtration bin is divided into a lower water collecting area, a middle water collecting area and an upper water collecting area from bottom to top; a water inlet of the lower water collecting area is communicated with an overflow port of the second clear water area through a pipeline, the upper water collecting area is communicated with the lower water collecting area through a pipeline, and a second circulating pump for driving water to flow from top to bottom is installed on the pipeline; a membrane assembly is installed in the middle water collecting area, and a water production pipe is inserted in the membrane assembly, one end of the water production pipe extends to outside of the membrane filtration bin.

[0008] Further, an aeration mechanism is installed on the inner bottom of the micro-electrolysis reaction bin, the Fenton reaction bin and the membrane filtration bin.

[0009] Further, the micro-electrolysis filler area is divided into multiple layers by a grid plate, and each layer is filled with micro-electrolysis filler; the micro-electrolysis filler is cobble-shaped iron-carbon composite material and is filled in a plurality of specifications of composite material flexible mesh bags.

[0010] Further, a plurality of backwashing cleaning pipes and backwashing aeration pipes are installed circumferentially in the micro-electrolysis reaction bin; the backwashing cleaning pipes and the backwashing aeration pipes longitudinally penetrate the micro-electrolysis filler area.

[0011] Further, the membrane assembly is composed of a plurality of soft film sheets, a dynamic membrane layer is formed on the surface of the membrane assembly by stacking membrane layer materials, and the dynamic membrane layer material is composed of two or three of active carbon, diatomite and talc powder.

[0012] Further, the neutralizing liquid is an acid-base liquid, and the reaction liquid is a strong oxidant.

[0013] Further, a sampling port is arranged on the pipeline between the first clear water area and the second mixing area, and between the second clear water area and the lower water collecting area.

[0014] Further, a pressure gauge and a rotor flowmeter are arranged on the water production pipe.

[0015] Further, a demister is installed on the inner top of the micro-electrolysis reaction bin and the Fenton reaction bin.

[0016] The wastewater treatment device of the above micro-electrolysis coupled Fenton, by backflowing part of the wastewater into the first mixing area to the first clear water area, improves the mass transfer of the wastewater, and real-time flushes the micro-electrolysis filler, preventing the agglomeration and passivation of the micro-electrolysis filler. By making another part of the wastewater into the first clear water area overflow into the second mixing area to mix with the reaction liquid in the second mixing area, the device can fully utilize the ferrous ions generated by the micro-electrolysis reaction by adjusting the wastewater residence time in the micro-electrolysis reaction bin, the water inlet pH in the micro-electrolysis reaction bin, etc., reducing the amount of reagent added, and at the same time, the matching of the amount of iron ions in the Fenton reaction bin and the reaction liquid can be controlled, and the wastewater treatment effect is better. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the micro-electrolysis reaction bin;

[0018] Figure 2 It is a structural schematic diagram of the Fenton reaction bin;

[0019] Figure 3 It is a structural schematic diagram of the membrane filtration bin.

[0020] In the figure: 100, micro-electrolysis reaction bin; 110, first mixing area; 120, micro-electrolysis filler area; 130, first clear water area; 140, first circulating pump; 150, backwashing cleaning pipe; 160, backwashing aeration pipe; 200, Fenton reaction bin; 210, second mixing area; 220, second clear water area; 230, iron salt injection pipe; 300, membrane filtration bin; 310, lower water collecting area; 320, middle water collecting area; 330, upper water collecting area; 340, second circulating pump; 350, membrane assembly; 360, water production pipe; 370, pressure gauge; 380, rotor flowmeter; 400, aeration mechanism. DETAILED DESCRIPTION

[0021] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] For example, Figure 1 and Figure 2As shown, in one embodiment, a wastewater treatment device of micro-electrolysis coupled with Fenton, comprises: a micro-electrolysis reaction bin 100, the internal cavity is divided into a first mixing area 110 for mixing wastewater and neutralizing liquid, a micro-electrolysis filler area 120 for micro-electrolysis of wastewater, and a first clear water area 130 for collecting treated wastewater from bottom to top; the first clear water area 130 and the first mixing area 110 are connected by a pipeline, and a first circulating pump 140 for driving water to flow from bottom to top is installed on the pipeline; a Fenton reaction bin 200, the internal cavity is divided into a second mixing area 210 for mixing wastewater and reaction liquid, and a second clear water area 220 for collecting treated wastewater from bottom to top; the water inlet of the second mixing area 210 and the overflow outlet of the first clear water area 130 are connected by a pipeline.

[0023] In use, the pH of the refractory wastewater needs to be adjusted and controlled between 1.5-5, and the SS is less than 200. The wastewater is delivered to the first mixing area 110 by a lifting pump, the wastewater entering the first mixing area 110 is mixed with the backflow water of the first clear water area 130, and the pH of the wastewater is adjusted by the neutralizing liquid added to the first mixing area 110. Then the wastewater passes through the micro-electrolysis filler area 120, part of which enters the second mixing area 210 through the overflow outlet, and the other part backflows to the first mixing area 110 through the pipeline. The wastewater entering the second mixing area 210 is mixed with the reaction liquid and reacts, and then flows out from the overflow outlet of the Fenton reaction bin 200 after being treated by the Fenton reaction bin 200.

[0024] The above-mentioned wastewater treatment device of micro-electrolysis coupled with Fenton can improve the mass transfer of wastewater by backflowing part of the wastewater entering the first clear water area 130 to the first mixing area 110, and can real-time flush the micro-electrolysis filler to prevent the agglomeration and passivation of the micro-electrolysis filler. By making another part of the wastewater entering the first clear water area 130 overflow into the second mixing area 210 and mix with the reaction liquid in the second mixing area 210, the device can fully utilize the ferrous ions generated by the micro-electrolysis reaction by adjusting the wastewater residence time in the micro-electrolysis reaction bin 100, the inlet water pH in the micro-electrolysis reaction bin 100, etc., thereby reducing the amount of reagent added, and can control the matching of the amount of iron ions in the Fenton reaction bin 200 and the reaction liquid, so that the wastewater treatment effect is better.

[0025] In this embodiment, the neutralizing liquid is an acid-base liquid, which is used to adjust the acid-base value of the wastewater. The reaction liquid is a strong oxidant, such as hydrogen peroxide, which is used to oxidize the pollutants in the wastewater.

[0026] As Figure 3As shown, in the present embodiment, the wastewater treatment device further comprises a membrane filtration bin 300, the internal cavity of the membrane filtration bin 300 is divided into a lower water collecting area 310, a middle water collecting area 320 and an upper water collecting area 330 from bottom to top; the water inlet of the lower water collecting area 310 is communicated with the overflow port of the second clear water area 220 through a pipeline, the upper water collecting area 330 is communicated with the lower water collecting area 310 through a pipeline, and a second circulating pump 340 for driving water to flow from top to bottom is installed on the pipeline; a membrane assembly 350 is installed in the middle water collecting area 320, water production pipes 360 are inserted in the membrane assembly 350, and one end of the water production pipes 360 extends to the outside of the membrane filtration bin 300.

[0027] When the wastewater flows through the membrane assembly 350, it is discharged from the water production pipes 360 under the action of the negative pressure suction pump. The second circulating pump 340 transports the wastewater in the upper water collecting area 330 to the lower water collecting area 310, thereby improving the uniformity of liquid mixing and the washing effect on the surface of the membrane assembly 350.

[0028] In the present embodiment, an aeration mechanism 400 is installed on the inner bottom of the micro-electrolysis reaction bin 100, the Fenton reaction bin 200 and the membrane filtration bin 300. The wastewater is fully mixed and reacted with acidic or alkaline liquid or strong oxidizing agent. The utilization rate of hydrogen peroxide is improved, the sludge yield is low, the wastewater utilization rate is high, and the amount of reagent added is small.

[0029] In the present embodiment, sampling ports are arranged on the pipelines between the first clear water area 130 and the second mixing area 210, and between the second clear water area 220 and the lower water collecting area 310. The sampling ports are used for detecting water quality, so as to regularly detect the COD (Chemical Oxygen Demand) concentration, iron ion concentration, SS and other indicators in the wastewater.

[0030] In the micro-electrolysis Fenton reaction, the ratio of the amount of hydrogen peroxide added to the COD detected by the sampling port between the first clear water area 130 and the second mixing area 210 is 0.5-4, and the ratio of the amount of ferrous ion in the Fenton reaction to the amount of hydrogen peroxide is n (H2O2): n (Fe 2+ ) = 50:1-2:1. It is to be noted that the overflow port of the Fenton reaction bin 200 is 50-60 cm lower than the overflow port of the micro-electrolysis reaction bin 100.

[0031] In the present embodiment, the micro-electrolysis filler area 120 is divided into multiple layers by grid plates, and each layer is filled with micro-electrolysis filler. The micro-electrolysis filler is cobble-shaped iron-carbon composite material with a particle size of 2-5 cm, and is filled in flexible mesh bags of multiple specifications, so as to facilitate the removal and filling of the filler.

[0032] In the embodiment, a plurality of backwashing cleaning pipes 150 and backwashing aeration pipes 160 are installed circumferentially in the micro-electrolysis reaction bin 100, for example, 6 pipes are installed. The backwashing cleaning pipes 150 and the backwashing aeration pipes 160 longitudinally penetrate the micro-electrolysis filler area 120. By periodically starting the backwashing aeration and the backwashing cleaning water to clean and maintain the micro-electrolysis filler, the micro-electrolysis filler is prevented and eliminated from being hardened and passivated, and the micro-electrolysis reaction device is kept in high-efficiency and stable operation.

[0033] In the embodiment, a plurality of iron salt injection pipes 230 are installed in the Fenton reaction bin 200.

[0034] In the embodiment, the membrane assembly 350 is composed of a plurality of soft film pieces, and a dynamic membrane layer is formed on the surface of the membrane assembly 350 by stacking membrane layer materials. The dynamic membrane layer material is composed of two or three of the three powdered particles of activated carbon, diatomite and talc powder.

[0035] In the embodiment, the membrane assembly 350 is composed of 40-75 soft film pieces, the membrane pore size is 0.1-20 microns, and the material of the dynamic membrane layer is selected from 200-350 mesh activated carbon, diatomite or talc powder.

[0036] The dynamic membrane layer has good solid-liquid separation effect, solves the problem of separation of small particles after micro-electrolysis Fenton reaction, has strong anti-pollution ability and strong adaptability due to the special surface structure of the membrane assembly 350, the membrane is resistant to acid and alkali, the membrane flux is high, the service life is long, and the device can be operated stably for a long time.

[0037] In the embodiment, a pressure gauge 370 and a rotor flowmeter 380 are arranged on the water production pipe 360. The flow rate and flow of the effluent are detected. A defoaming machine is installed on the inner top of the micro-electrolysis reaction bin 100 and the Fenton reaction bin 200. The defoaming machine is used to eliminate the foam that may be generated in the device. A waste gas collection pipe is installed on the inner top of the micro-electrolysis reaction bin 100, the Fenton reaction bin 200 and the membrane filtration bin 300. The waste gas collection pipe is used to collect the toxic and harmful gases that may be generated in the wastewater treatment process.

[0038] Based on the coupling of the micro-electrolysis reaction bin 100, the Fenton reaction bin 200 and the membrane filtration bin 300, the purpose of adjustable, controllable and resource utilization of ferrous ions in the micro-electrolysis effluent is achieved, and the device has the effects of low treatment cost, small land occupation, small amount of reagent addition, small amount of sludge production, low effluent SS, and continuous and stable operation.

[0039] The effects of the above device in actual use are shown in the form of data as follows:

[0040] 1. The wastewater source is mixed dye wastewater generated in the process of producing dyes in a certain dye factory, the wastewater has COD = 22000-25000 mg / l, pH = 1.6, chroma is more than 10000 times, B / C of the wastewater is less than 0.1, SS is more than 10000, and the wastewater is black. Table 1 shows the water quality test results of Example 1 (unit: mg / l)

[0041] COD Fe 3+ / Fe 2+ ]]> SS B / C Mixed dye wastewater raw solution 24000 120 280 0.08 Sample port 1 micro electrolysis effluent 22000 1100 415 0.32 Sample port 2 Fenton effluent 9000 1000 480 0.36 Sample port 3 membrane filtration effluent 8800 520 6 0.36

[0042] 2. The wastewater source is printing and dyeing wastewater generated in a certain printing and dyeing factory, the wastewater has COD = 2000-2500 mg / l, pH = 6.8, chroma is more than 10000 times, B / C of the wastewater is 0.12, and SS is 90. Table 2 shows the water quality test results of Example 2 (unit: mg / l)

[0043] COD Fe 3+ / Fe 2+ ]]> SS B / C Mixed dye wastewater raw solution 2100 10 90 0.12 Sample port 1 micro electrolysis effluent 1356 400 260 0.38 Sample port 2 Fenton effluent 760 320 290 0.39 Sample port 3 membrane filtration effluent 750 280 4 0.39

[0044] The above-mentioned examples only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the scope of protection of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A wastewater treatment device with micro-electrolysis coupled Fenton, characterized in that, include: The micro-electrolysis reaction chamber is divided into three internal sections from bottom to top: a first mixing zone for mixing wastewater and neutralizing liquid, a micro-electrolysis packing zone for micro-electrolysis of wastewater, and a first clear water zone for collecting treated wastewater. The first clear water zone and the first mixing zone are connected by a pipe, and a first circulation pump for driving water flow from top to bottom is installed on the pipe. The micro-electrolysis packing is a pebble-shaped iron-carbon composite material. The first clear water zone is equipped with an overflow port, which is located above the top of the connecting pipe between the first clear water zone and the first mixing zone. The Fenton reaction chamber has an internal cavity that is divided from bottom to top into a second mixing zone for mixing wastewater and reaction liquid, and a second clear water zone for collecting treated wastewater. The inlet of the second mixing zone is connected to the overflow of the first clear water zone through a pipe. The overflow of the Fenton reaction chamber is 50-60 cm lower than the overflow of the micro-electrolysis reaction chamber. The membrane filtration chamber is internally divided into a lower collection zone, a middle collection zone, and an upper collection zone from bottom to top. The inlet of the lower collection zone is connected to the overflow outlet of the second clear water zone via a pipe, and the upper collection zone is connected to the lower collection zone via a pipe. A second circulation pump is installed on this pipe to drive the water flow from top to bottom. The middle collection zone contains a membrane module with a product water pipe inserted inside. One end of the product water pipe extends to the outside of the membrane filtration chamber. The membrane module consists of 40 to 75 flexible membrane sheets with a pore size of 0.1 to 20 micrometers. A dynamic membrane layer is formed by depositing membrane material on the surface of the membrane module. The material of the dynamic membrane layer is selected from 200 to 350 mesh activated carbon, diatomaceous earth, or talc. During use, the pH of the recalcitrant wastewater needs to be adjusted to between 1.5 and 5. A sampling port is installed on the pipeline between the first clear water zone and the second mixing zone. In the micro-electrolysis Fenton reaction, the ratio of the amount of hydrogen peroxide added to the COD detected at this sampling port is 0.5–4. The ratio of ferrous ions to hydrogen peroxide in the Fenton reaction is n(H₂O₂):n(Fe₂O₃). 2+ = 50:1 to 2:

1.

2. The wastewater treatment device with micro-electrolysis coupling Fenton as described in claim 1, characterized in that, The bottom of the micro-electrolysis reaction chamber, the Fenton reaction chamber, and the membrane filtration chamber are all equipped with an aeration mechanism.

3. The wastewater treatment device with micro-electrolysis coupling Fenton as described in claim 1, characterized in that, The micro-electrolysis filler area is divided into multiple layers by a grid plate, and each layer is filled with micro-electrolysis filler; the micro-electrolysis filler is respectively filled in flexible mesh bags of composite materials of various specifications.

4. The wastewater treatment device with micro-electrolysis coupling Fenton as described in claim 1, characterized in that, The micro-electrolysis reaction chamber is equipped with multiple backwash cleaning pipes and backwash aeration pipes circumferentially; the backwash cleaning pipes and backwash aeration pipes longitudinally penetrate the micro-electrolysis packing area.

5. The wastewater treatment device with micro-electrolysis coupling Fenton as described in claim 1, characterized in that, The neutralizing solution is an acidic or alkaline liquid.

6. The wastewater treatment device with micro-electrolysis coupling Fenton as described in claim 1, characterized in that, A sampling port is provided on the pipeline between the second clear water zone and the lower water collection zone.

7. The wastewater treatment device with micro-electrolysis coupling Fenton as described in claim 1, characterized in that, The water production pipe is equipped with a pressure gauge and a rotor flow meter.

8. The wastewater treatment device with micro-electrolytic coupling Fenton as described in claim 1, characterized in that, Both the micro-electrolysis reaction chamber and the Fenton reaction chamber are equipped with demisters at their inner tops.

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