Distributed landfill leachate treatment device and method based on plant bionics

Abstract

The invention discloses a distributed landfill leachate treatment device and method based on plant bionics. The device comprises a bionic trunk and bionic blades, and each bionic blade comprises a porous base layer, a capillary tube and a photothermal conversion layer; the method comprises the following steps: uniformly mixing a peroxydisulfate oxidizing agent and the landfill leachate, conveying the landfill leachate to the bionic blades through the bionic trunk, and permeating and dispersing the landfill leachate in the porous base layer through the capillary tubes; the photo-thermal conversion layer absorbs heat converted by sunlight to activate a peroxydisulfate oxidizing agent to oxidize and degrade organic pollutants in the landfill leachate, and meanwhile, the landfill leachate in the leaves is evaporated; according to the invention, low-cost and high-efficiency treatment of the landfill leachate is realized; due to the oxidation effect of the thermally activated persulfate, water vapor generated in the evaporation process is purified, moisture volatilized into the air is odorless, and the surrounding air is not polluted; and the method has a good application prospect in the scenes of garbage storage stations, transfer stations, small garbage plants and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of landfill leachate treatment, and particularly relates to a decentralized landfill leachate treatment device and method based on plant bionics. Background Art

[0002] Landfill leachate is a kind of wastewater generated during the collection, transportation, landfill, and pre-incineration storage processes of garbage. Landfill leachate contains a large amount of toxic and harmful substances, such as heavy metals, high-concentration organic matter, and salts, and belongs to typical difficult-to-treat wastewater. Due to the poor treatment effect of traditional treatment technologies on the refractory organic matter in landfill leachate, new advanced treatment technologies need to be developed to meet the full-quantification treatment of landfill leachate.

[0003] Advanced oxidation technology is commonly used for the deep purification of refractory organic pollutants in landfill leachate, relying on strongly oxidizing free radical active species to decompose pollutants. Among them, the thermal activation of persulfate advanced oxidation technology uses heat energy to decompose persulfate, generating active species such as sulfate radicals and hydroxyl radicals. However, the existing technology consumes a large amount of heat energy for heating the water body, which limits the application prospect of this technology.

[0004] Evaporation treatment technology is commonly used for the full-quantification treatment of landfill leachate, which can separate water, refractory organic matter, and salts. However, the evaporation treatment technology also faces the problem of high energy consumption, and reducing the energy consumption of landfill leachate treatment is an urgent concern for enterprises.

[0005] Therefore, it is very necessary to develop a decentralized landfill leachate treatment device and method based on plant bionics that can solve the above problems. Summary of the Invention

[0006] The first object of the present invention is to provide a decentralized landfill leachate treatment device based on plant bionics.

[0007] The second object of the present invention is to provide a treatment method for the decentralized landfill leachate treatment device based on plant bionics.

[0008] The first object of the present invention is achieved as follows: it includes a bionic trunk and bionic leaves. The bionic trunk is columnar, and the material is a porous material. The bionic leaves include a porous base layer, capillary tubes, and a photothermal conversion layer. The capillary tubes are distributed in a vein-like pattern on the porous base layer. The capillary tube walls are provided with permeation holes. The photothermal conversion layer is provided on the porous base layer, and the capillary tubes are located below the photothermal conversion layer. The bionic leaves are provided on the bionic trunk, and the capillary inlet ends of the bionic trunk and the bionic leaves are connected.

[0009] Preferably, the porous material used for the bionic trunk is several tubular materials with a hollow structure, specifically, it can be plastic fiber tubes, glass fiber tubes, or polymer organic fiber tubes.

[0010] Preferably, the porous base material is polyurethane foam or metal foam.

[0011] Preferably, the capillary is a plastic fiber tube, a glass fiber tube, a PVDF membrane filament tube or a PTFE membrane filament tube.

[0012] Preferably, the photothermal conversion layer is formed by coating a mixture of a photothermal conversion material and a binder on the porous base. The photothermal conversion material is one or more of carbon materials (such as carbon black), semiconductor materials, metal nanoparticles, and MXene mixed powder materials, and the binder is PTFE, epoxy resin, polyurethane or acrylic acid.

[0013] Preferably, the vein-like distribution specifically refers to the main veins and the branch veins arranged on both sides of the main veins, and the ends of adjacent branch veins on the same side are either connected or not connected.

[0014] Preferably, a delivery pump is further included, and the delivery pump is connected to the bionic torso; if the local sunlight is sufficient, the height of the bionic torso can be reduced, and the leachate can spontaneously enter the bionic torso and bionic leaves by capillary action and transpiration, without the need for a delivery pump.

[0015] The second object of the present invention is achieved as follows, including the following steps: S1. Mix the persulfate oxidant with the leachate evenly, and the addition concentration of the persulfate oxidant is 0.1 mmol / L to 10 mmol / L; S2. The leachate is transported to the bionic leaves through the bionic torso, and penetrates through the capillary and is dispersed in the porous base; S3. The heat converted by the photothermal conversion layer absorbing sunlight activates the persulfate oxidant to oxidize and degrade the organic pollutants in the leachate, and at the same time evaporates the leachate in the leaves.

[0016] Preferably, in step S1, the persulfate oxidant is sodium persulfate and / or ammonium persulfate.

[0017] Preferably, in step S3, the activation temperature is greater than 40 °C to achieve effective activation of the persulfate.

[0018] The beneficial effects of the present invention: 1. The treatment device of the present invention is designed based on the plant bionic structure, and the staggered bionic leaves can make the most of the vertically distributed solar energy, improving the utilization efficiency of sunlight in the area; 2. The method of the present invention combines the advantages of the advanced oxidation technology of thermally activated persulfate for efficient decomposition of organic pollutants, achieving low-cost and efficient treatment and disposal of landfill leachate; due to the oxidation of thermally activated persulfate, the water vapor generated during the evaporation process is purified, and the water volatilized into the air has no odor and does not pollute the surrounding air; it has good application prospects in the field of decentralized landfill leachate such as garbage storage stations, transfer stations, and small landfill / incineration plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic structural diagram of the treatment device of the present invention; Figure 2 It is a schematic diagram of the three-layer structure of the bionic leaf; Figure 3 It is a schematic diagram of the structure where the ends of the adjacent branch veins on the same side of the bionic leaf are not connected; Figure 4 It is a schematic diagram of the structure where the ends of the adjacent branch veins on the same side of the bionic leaf are connected; In the figure: 1 - bionic trunk, 2 - bionic leaf, 201 - porous base layer, 202 - capillary, 203 - photothermal conversion layer, 3 - landfill leachate collection pool, 4 - landfill leachate injection port. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The present invention will be further described below in conjunction with the embodiments and the drawings, but it is not limited to the present invention in any way. Any transformation or replacement based on the teachings of the present invention belongs to the protection scope of the present invention.

[0021] Embodiment 1 As shown in the attached Figures 1 to 3As shown, the present embodiment is a decentralized landfill leachate treatment device based on plant bionics, comprising a bionic trunk 1 and a bionic blade 2. The bionic trunk 1 is columnar, and is composed of a PVDF membrane silk tube filled in a PVC tube. The inner diameter of the PVDF membrane silk tube is 1.5 mm, and the inner diameter of the PVC tube is 2 cm. The bionic blade 2 comprises a porous base 201, a capillary 202, and a photothermal conversion layer 203. The porous base 201 is made of polyurethane foam with a thickness of 3 mm. The capillary 202 is a PVDF membrane silk tube with an inner diameter of 1.5 mm. The photothermal conversion layer 203 is a photothermal conversion material mixed with a binder and coated on the porous base 201 with a thickness of 0.2 mm. The capillary 202 is distributed on the porous base 201 in the shape of leaf veins. The wall of the capillary 202 is provided with a penetration hole with a pore size of 2 μm. The leaf vein-like distribution is specifically the main leaf vein and the branch leaf veins arranged on both sides of the main leaf vein. The ends of adjacent branch leaf veins on the same side are not connected. The conversion layer 203 is arranged on the porous base layer 201, and the capillary 202 is located below the photothermal conversion layer 203, wherein the photothermal conversion layer 203 is a mixture of photothermal conversion material and binder (binder dosage: 1% by mass) and then coated on the porous base layer 201, the photothermal conversion material is a MXene mixed powder (carbon black and Ti3C2Mxene are uniformly mixed in a mass ratio of 2:1), and the binder is PTFE. The bionic blades 2 are staggeredly arranged on the bionic trunk 1, and the PVDF membrane filament tubes of the bionic trunk 1 are connected one by one with the inlet ends of the PVDF membrane filament tubes of the main veins of the bionic blades 2, and the lower end of the bionic trunk 1 is connected to the peristaltic pump latex tube and a peristaltic pump is set.

[0022] Example 2 As attached Figure 4 As shown, the decentralized landfill leachate treatment device based on plant bionics in this embodiment is based on Example 1, and is different from Example 1 in that the ends of adjacent branch veins on the same side are connected, the porous material used in the bionic trunk 1 is a glass fiber tube with an inner diameter of 2 mm, the porous base layer 201 material is copper foam, the capillary 202 is a perforated glass fiber tube with an inner diameter of 2 mm, the photothermal conversion material is TiO2 powder, the binder is epoxy resin, and the binder dosage is 1.5%.

[0023] Example 3 As attached Figure 3 The decentralized landfill leachate treatment device based on plant bionics in this embodiment is based on Example 1, and the difference from Example 1 is that the porous material used in the bionic trunk 1 is a PVDF hollow fiber membrane with an inner diameter of 1 mm, the capillary 202 is a PTFE membrane tube with an inner diameter of 1 mm and a pore size of 5 μm, the photothermal conversion material is carbon black, the binder is polyurethane, and the binder dosage is 1.5%.

[0024] Example 4 This embodiment is a treatment method of the decentralized landfill leachate treatment device based on plant bionics in Embodiment 1, including the following steps: S1. Mix sodium persulfate evenly with the landfill leachate, and the added concentration of sodium persulfate is 1 mmol / L; S2. The landfill leachate is transported to the bionic leaf 2 through the bionic trunk 1, and penetrates through the capillary 202 and is dispersed in the porous base layer 201; S3. The photothermal conversion layer 203 absorbs the heat converted by sunlight to activate sodium persulfate to oxidize and degrade the organic pollutants in the landfill leachate, and at the same time evaporates the landfill leachate in the leaf; Under the condition of sunlight irradiation, the device evaporated a total of 2.9 L of landfill leachate from 9:00 to 19:00. The water vapor generated by evaporation was collected, and after condensation, the COD of the condensed water was measured to be 2.6 mg / L, the ammonia nitrogen concentration was 0.52 mg / L, and the highest temperature of the bionic leaf was 61.2 °C.

[0025] Embodiment 5 This embodiment is a treatment method of the decentralized landfill leachate treatment device based on plant bionics in Embodiment 1. Except that ammonium persulfate is used in step S1 and the added concentration is 10 mmol / L, the rest is the same as Embodiment 4; Under the condition of sunlight irradiation, the device evaporated a total of 3.2 L of landfill leachate from 9:00 to 19:00. The water vapor generated by evaporation was collected, and after condensation, the COD of the condensed water was measured to be 3.5 mg / L, and the ammonia nitrogen concentration was 0.69 mg / L.

[0026] Embodiment 6 This embodiment is a treatment method of the decentralized landfill leachate treatment device based on plant bionics in Embodiment 1. Except that a mixture of sodium persulfate and ammonium persulfate in a ratio of 1:1 is used in step S1, the rest is the same as Embodiment 4.

[0027] Embodiment 7 This embodiment is a treatment method of the decentralized landfill leachate treatment device based on plant bionics in Embodiment 1. Except that the added concentration in step S1 is 0.1 mmol / L, the rest is the same as Embodiment 4.

[0028] Embodiment 8 This embodiment is a treatment method of the decentralized landfill leachate treatment device based on plant bionics in Embodiment 1. Except that the added concentration in step S1 is 5 mmol / L, the rest is the same as Embodiment 4.

Claims

1. A decentralized landfill leachate treatment device based on plant bionics, characterized in that The bionic blade (2) comprises a bionic trunk (1) and a bionic blade (2); the bionic trunk (1) is columnar and made of a porous material; the bionic blade (2) comprises a porous base layer (201), capillaries (202), and a light-heat conversion layer (203); the capillaries (202) are distributed on the porous base layer (201) in a vein-like manner; the walls of the capillaries (202) are provided with permeable holes; the light-heat conversion layer (203) is arranged on the porous base layer (201), and the capillaries (202) are located below the light-heat conversion layer (203); the bionic blade (2) is arranged on the bionic trunk (1), and the capillaries (202) of the bionic blade (2) are connected to the inlet ends of the capillaries (202).

2. The plant biomimetic decentralized landfill leachate treatment device according to claim 1 is characterized in that The porous material used in the bionic trunk (1) is a plurality of tubular materials with a hollow structure.

3. The plant biomimetic decentralized landfill leachate treatment device according to claim 1 is characterized in that The porous base layer (201) is made of polyurethane foam or foam metal.

4. The plant biomimetic decentralized landfill leachate treatment device according to claim 1 is characterized in that The capillary tube (202) is a plastic fiber tube, a glass fiber tube, a PVDF membrane fiber tube, or a PTFE membrane fiber tube.

5. The plant biomimetic decentralized landfill leachate treatment device according to claim 1 is characterized in that The photothermal conversion layer (203) is a mixture of a photothermal conversion material and a binder and is coated on the porous base layer (201); the photothermal conversion material is one or more of a carbon material, a semiconductor material, metal nanoparticles, and a MXene mixed powder material; and the binder is PTFE, epoxy resin, polyurethane, or acrylic acid.

6. The plant biomimetic decentralized landfill leachate treatment device according to claim 5 is characterized in that The vein-like distribution specifically refers to the main vein and the branch veins arranged on both sides of the main vein, and the ends of adjacent branch veins on the same side are connected or not connected.

7. The plant biomimetic decentralized landfill leachate treatment device according to claim 1 is characterized in that It also includes a delivery pump, which is connected to the bionic trunk (1).

8. A method for treating landfill leachate according to any one of claims 1 to 7, characterized in that The following steps are involved: S1. Evenly mix the peroxydisulfate oxidant and the landfill leachate, wherein the concentration of the peroxydisulfate oxidant is 0.1 mmol / L to 10 mmol / L; S2, the landfill leachate is transported to the bionic blade (2) through the bionic trunk (1), penetrates through the capillary (202) and is dispersed in the porous base layer (201); S3. The light-to-heat conversion layer (203) absorbs the heat converted from sunlight to activate the peroxydisulfate oxidant to oxidize and degrade the organic pollutants in the landfill leachate, while evaporating the landfill leachate in the leaves.

9. The processing method according to claim 8, characterized in that The disulfate oxidant in step S1 is sodium peroxodisulfate and / or ammonium peroxodisulfate.

10. The processing method according to claim 8, characterized in that The activation temperature in step S3 is greater than 40°C.

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