Glufosinate-ammonium wastewater recycling device

Abstract

The utility model relates to a glufosinate-ammonium wastewater resource recycling device, which comprises a reaction device for carrying out biochemical degradation reaction on glufosinate-ammonium wastewater; the settling tank is connected to the reaction device and is used for settling the wastewater generated by the reaction device; the ceramic membrane is connected to the sedimentation tank and is used for filtering the wastewater subjected to sedimentation treatment in the sedimentation tank; the nanofiltration membrane is connected to the permeation side of the ceramic membrane and is used for carrying out nanofiltration treatment on permeate liquid of the ceramic membrane; the advanced oxidation equipment is connected to the permeation side of the nanofiltration membrane and is used for carrying out oxidation treatment on permeate obtained by the nanofiltration membrane; the reverse osmosis membrane is connected to the advanced oxidation equipment and is used for carrying out salt concentration treatment on the wastewater subjected to oxidation treatment; and the evaporator is connected to the interception side of the reverse osmosis membrane and is used for carrying out evaporative crystallization on the obtained salt concentrated solution to obtain NaCl salt. According to the device, sodium chloride can be extracted from saline water containing organic matters, organic phosphorus and sodium sulfate / sodium chloride, and purified water is reused in the production process.

Description

Technical Field

[0001] This utility model relates to a glufosinate wastewater resource recycling device, belonging to the technical field of high organic phosphate salt resource utilization. Background Technology

[0002] Glufosinate is a non-selective contact herbicide. Its main production process involves the Grignard reaction, addition reaction, hydrochloric acid acidification, and ammoniaation of triethyl methyl phosphite to obtain glufosinate. Glufosinate wastewater is characterized by high COD and high phosphorus content, making it a difficult-to-treat pesticide industrial wastewater. Currently, the main treatment methods for glufosinate wastewater include biochemical methods, incineration, and membrane methods. Among these, incineration consumes a huge amount of energy, while biochemical methods have a long cycle time.

[0003] First, the presence of high concentrations of organophosphorus compounds and toxic organic matter not only affects the efficiency of biochemical systems but may also cause eutrophication of water bodies. Second, large amounts of inorganic salts, especially sodium chloride and sodium sulfate, if directly discharged into the environment, will cause environmental problems such as soil salinization and water pollution, seriously violating the principles of sustainable development.

[0004] Chinese patent CN106115974A discloses a method for pretreating glufosinate-containing phosphorus wastewater using a complexation and centrifugal coupling approach. By selecting appropriate complexing agent components, reaction temperature, and centrifugal speed, suspended solids in the glufosinate-containing phosphorus wastewater are formed into waste residue, and the centrifuged liquid undergoes subsequent biochemical treatment. However, this method does not provide the effectiveness of the subsequent biochemical treatment, and the toxicity of the pesticide wastewater inhibits biochemical processes, resulting in the wastewater failing to meet discharge standards.

[0005] Therefore, how to efficiently, economically, and environmentally treat this glufosinate wastewater has become a pressing technical challenge for the glufosinate industry. Currently, researchers are actively exploring various methods, such as resource utilization (e.g., extracting valuable industrial salt), advanced treatment (e.g., further purification using advanced oxidation and membrane separation technologies), and reuse technologies (e.g., reusing properly treated wastewater in the glufosinate production process), in order to maximize resource utilization and minimize waste emissions, thereby promoting the green upgrading and sustainable development of the glufosinate industry. Summary of the Invention

[0006] To address the aforementioned issues, there is an urgent need to develop an efficient and low-cost technology for the reuse of water and the extraction of salt resources from glufosinate wastewater. This technology would solve the water shortage problem while recovering economically valuable inorganic salts, thereby reducing the cost of zero-emission operation.

[0007] This invention provides a method for the resource recovery and reuse of glufosinate wastewater. This method effectively removes solid impurities from glufosinate wastewater, obtains sodium chloride inorganic salt resources from the mixed salt solution, and simultaneously achieves high-recovery pure water reuse in upstream production processes, realizing the resource recovery of sodium chloride and water recycling from glufosinate wastewater. The main process involves removing solid impurities through inorganic membrane treatment, followed by initial purification of the glufosinate wastewater, which then enters a nanofiltration system, an advanced oxidation system, a reverse osmosis system, and an evaporation crystallization system. This yields high-purity industrial-grade sodium chloride and pure water, which is then reused in upstream production processes, thus achieving the resource recovery of glufosinate wastewater.

[0008] A method for the resource recovery and reuse of glufosinate wastewater includes the following steps:

[0009] Step 1: Add the glufosinate to the wastewater produced during the glufosinate production process and then filter it through a ceramic membrane.

[0010] Step 2: The permeate from the ceramic membrane is subjected to nanofiltration to remove salts and total phosphorus, yielding a sodium chloride solution;

[0011] Step 3: Perform advanced oxidation reaction on the sodium chloride brine to obtain brine with lower organic matter content;

[0012] Step 4: The brine with low organic content is concentrated by reverse osmosis to obtain recycled water, which will be used in the production process.

[0013] Step 5: Evaporate and crystallize the reverse osmosis concentrate to obtain industrial-grade sodium chloride.

[0014] The wastewater from the glufosinate production process contains sodium sulfate, sodium chloride, organophosphates, and organic matter.

[0015] The wastewater from the glufosinate process is the glufosinate production wastewater after biochemical treatment; the water contains 0.5-20 g / L NaCl and Mg. 2+ 0.001-0.5 g / L, Ca 2+ 0.005-0.5 g / L, COD 100-1000 mg / L, total phosphorus 1-100mg / L, Na2SO41-1000mg / L.

[0016] The ceramic membrane has an average pore size of 0.002 μm to 1 μm, or a molecular weight cutoff of 10,000 to 5,000,000 Da.

[0017] The operating pressure range of the ceramic membrane is 0.05-0.3 MPa, and it adopts cross-flow velocity filtration with a flow rate of 0.01-5 m / s.

[0018] During the filtration process of ceramic membranes, a filter aid is added to the feed, with an addition amount of 0.5-5%.

[0019] The filter aid is one of the following: diatomaceous earth, perlite, cellulose, asbestos, graphite powder, sawdust, magnesium oxide, gypsum, activated carbon, and acid clay.

[0020] The temperature for evaporation and fractional crystallization is controlled at 50℃~95℃, and more preferably 70~80℃.

[0021] The reverse osmosis membrane filtration process operates at a pressure of 0.5MPa~12MPa. The reverse osmosis membrane material is selected from one or a combination of PA, PP, PEEK, PES, PET, PVDF, etc.

[0022] The glufosinate wastewater resource recovery and reuse device includes:

[0023] The reaction apparatus is used for the biochemical degradation reaction of glufosinate wastewater;

[0024] A settling tank, connected to the reaction device, is used to settle the wastewater generated by the reaction device;

[0025] A ceramic membrane is attached to a sedimentation tank to filter wastewater that has undergone sedimentation treatment.

[0026] Nanofiltration membranes are attached to the permeate side of ceramic membranes and are used to perform nanofiltration treatment on the permeate from the ceramic membrane.

[0027] Advanced oxidation equipment, connected to the permeate side of a nanofiltration membrane, is used to oxidize the permeate obtained from the nanofiltration membrane.

[0028] Reverse osmosis membranes are connected to advanced oxidation equipment and are used to concentrate salts in oxidized wastewater.

[0029] An evaporator, connected to the filtration side of the reverse osmosis membrane, is used to evaporate and crystallize the obtained salt concentrate to obtain NaCl salt.

[0030] It also includes: a filter aid dosing tank, used to add filter aids to the settling tank.

[0031] The aforementioned reaction apparatus is an A / O system, A 2 One of the / O systems.

[0032] The ceramic membrane can be configured as a single-tube, flat-plate, or multi-channel ceramic membrane.

[0033] The ceramic membrane has an average pore size of 0.002 μm to 1 μm, or a molecular weight cutoff of 10,000 to 5,000,000 Da.

[0034] The ceramic membrane is made of alumina, zirconium oxide, silicon carbide, or titanium oxide.

[0035] The advanced oxidation equipment mentioned is an ozone oxidation equipment.

[0036] Beneficial effects

[0037] The glufosinate wastewater recycling method of this invention can effectively solve the problem of water shortage while recovering economically valuable inorganic salts. Attached Figure Description

[0038] Figure 1 This is a process flow diagram of this utility model.

[0039] Figure 2 This is a diagram of the device of this utility model.

[0040] Figure 3 It is a flux decay curve.

[0041] The components include: 1. Reaction apparatus; 2. Sedimentation tank; 3. Filter aid addition tank; 4. Ceramic membrane; 5. Nanofiltration membrane; 6. Advanced oxidation equipment; 7. Reverse osmosis membrane; and 8. Evaporator. Detailed Implementation

[0042] This utility model relates to a method for the resource recovery and reuse of glufosinate wastewater. Specifically, it involves removing solid impurities through inorganic membrane treatment, achieving preliminary purification of the glufosinate wastewater, and then introducing it into a nanofiltration system, an advanced oxidation system, a reverse osmosis system, and an evaporation crystallization system to obtain high-purity industrial-grade sodium chloride and pure water. The pure water is then reused in the upstream production process, thereby realizing the resource recovery of glufosinate wastewater.

[0043] The approximations used herein may be used throughout the specification and claims to modify any quantity expression, which may be altered without changing its associated essential function. Therefore, values ​​modified by terms such as “about” are not limited to the specified exact values. In at least some cases, the approximation may correspond to the precision of the instrument used to measure the value. Unless otherwise indicated by context or statement, range boundaries may be combined and / or interchanged, and such ranges are defined as including all subrangements included herein. Except as specified in the operational examples or elsewhere, all figures or expressions representing amounts of ingredients, reaction conditions, etc., as used in the specification and claims should in all cases be understood to be modified by the word “about.”

[0044] The term "removal" in this specification includes not only the complete removal of the target substance but also the partial removal (reduction of the amount of the substance). The term "purification" in this specification includes the removal of any or specific impurities.

[0045] The terms “comprising,” “including,” “having,” or any other variations thereof as used herein are intended to cover non-exclusive inclusion. For example, a process, method, article, or apparatus that includes listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. It should be understood that when an element is referred to as being “connected” to another element, it may be directly connected to other elements or indirectly connected to other elements with elements inserted between them. Percentages mentioned in this invention refer to percentages by mass unless otherwise specified.

[0046] In the cases of treatable glufosinate wastewater, Examples 1-3 below describe wastewater that has undergone biochemical treatment after being generated during the production of glufosinate.

[0047] The glufosinate-ammonium wastewater resource recovery and reuse method in this patent includes the following steps:

[0048] Step 1: The glufosinate wastewater is subjected to a flocculation reaction with added chemicals, followed by filtration in a high-density sedimentation tank.

[0049] Step 2: The effluent from the high-density sedimentation tank is treated with an inorganic membrane to reduce suspended solids to <1 ppm;

[0050] Step 3: The inorganic membrane permeate is subjected to nanofiltration to separate sodium chloride brine from sulfates, organic matter, organophosphates, etc., to obtain sodium chloride brine with higher purity.

[0051] Step 4: Perform advanced oxidation reaction on the sodium chloride brine to obtain brine with lower organic matter content;

[0052] Step 5: The brine with low organic content is concentrated by reverse osmosis to obtain recycled water, which will be used in the production process.

[0053] Step 6: Evaporate and crystallize the reverse osmosis concentrate to obtain industrial-grade sodium chloride.

[0054] The wastewater from the glufosinate production process contains organic matter, organophosphates, sodium chloride, and sodium sulfate.

[0055] The wastewater from the glufosinate production process contains 0.5-20 g / L NaCl and Mg. 2+ 0.001-0.5 g / L, Ca 2+ 0.005-0.5 g / L, COD 100-1000 mg / L, total phosphorus 1-100mg / L, Na2SO41-1000mg / L.

[0056] The inorganic membrane has an average pore size of 0.002 μm to 1 μm, or a molecular weight cutoff of 10,000 to 5,000,000 Da; the inorganic membrane operates at a pressure range of 0.05-0.3 MPa and is filtered using a micro-crossflow velocity of 0.01-5 m / s.

[0057] During the filtration process of the ceramic membrane, sodium carbonate, sodium hydroxide, and filter aid are added to the feed at a rate of 0.5-5%. The filter aid is one of the following: diatomaceous earth, perlite, cellulose, asbestos, graphite powder, sawdust, magnesium oxide, gypsum, activated carbon, and acidic clay.

[0058] The nanofiltration membrane filtration process operates at a pressure of 0.5MPa~8MPa. The nanofiltration membrane material is selected from one or a combination of several of PA, PVC, PEEK, PES, PET, PVDF, etc.

[0059] The advanced oxidation reaction treatment is an ozone catalytic oxidation or ozone-hydrogen peroxide combined catalytic oxidation system; after advanced oxidation treatment, the organic matter removal rate of the effluent is 20%~70%.

[0060] The reverse osmosis membrane filtration process operates at a pressure of 0.5 MPa to 12 MPa. The reverse osmosis membrane material is selected from one or a combination of several of PA, PP, PEEK, PES, PET, and PVDF. The temperature control for evaporation and crystallization is 50℃ to 95℃, with 70℃ to 80℃ being more preferred.

[0061] Based on the above methods, the glufosinate wastewater resource recovery and reuse device in this patent includes:

[0062] Reaction device 1 is used to carry out a biochemical degradation reaction on glufosinate wastewater;

[0063] Sedimentation tank 2 is connected to reaction device 1 and is used to settle the wastewater generated by reaction device 1;

[0064] Ceramic membrane 4 is connected to sedimentation tank 2 and is used to filter the wastewater that has undergone sedimentation treatment in sedimentation tank 2.

[0065] Nanofiltration membrane 5 is connected to the permeate side of ceramic membrane 4 and is used to perform nanofiltration treatment on the permeate of ceramic membrane 4;

[0066] Advanced oxidation equipment 6 is connected to the permeate side of nanofiltration membrane 5 and is used to oxidize the permeate obtained from nanofiltration membrane 5;

[0067] The reverse osmosis membrane 7 is connected to the advanced oxidation equipment 6 and is used to concentrate the salt in the oxidized wastewater.

[0068] Evaporator 8, connected to the retentive side of reverse osmosis membrane 7, is used to evaporate and crystallize the obtained salt concentrate to obtain NaCl salt.

[0069] It also includes: filter aid addition tank 3, used to add filter aid to sedimentation tank 2.

[0070] The aforementioned reaction apparatus is an A / O system, A 2 One of the / O systems.

[0071] The ceramic membrane 4 is configured as a single tube, a flat plate, or a multi-channel ceramic membrane.

[0072] The ceramic membrane 4 has an average pore size of 0.002 μm to 1 μm, or a molecular weight cutoff of 10,000 to 5,000,000 Da.

[0073] The ceramic film 4 is made of alumina, zirconium oxide, silicon carbide or titanium oxide.

[0074] The advanced oxidation device 6 is an ozone oxidation device.

[0075] Example 1

[0076] After biochemical treatment, the glufosinate production wastewater contained 2.5 g / L NaCl and Mg. 2+ 0.01 g / L, Ca 2+ 0.02 g / L, COD 500 mg / L, Na₂SO₄ 0.8 g / L, TP 15 mg / L, filtered through a 50 nm ceramic membrane device at an operating pressure of 0.1 MPa and a cross-flow velocity of 0.1 m / s, can remove solids, yielding the ceramic membrane permeate. The ceramic membrane permeate is then fed into a nanofiltration membrane at an operating pressure of 3 MPa to obtain a sodium chloride solution. This sodium chloride solution is then fed into an ozone catalytic oxidation system with an ozone dosage of 0.5 g / L, achieving a COD removal rate of 45%, yielding a sodium chloride solution with a COD of 48 ppm. The concentrated sodium chloride solution from reverse osmosis is then evaporated and crystallized to obtain industrial-grade sodium chloride salt with a purity of 98.7%. Example 2

[0077] After biochemical treatment, the glufosinate production wastewater contains 3 g / L NaCl and Mg. 2+ 0.02 g / L, Ca 2+ 0.02 g / L, COD 400 mg / L, Na₂SO₄ 1 g / L, TP 12 mg / L, filtered through a 200 nm silicon carbide membrane device at an operating pressure of 0.1 MPa and a cross-flow velocity of 0.2 m / s, can remove solids. The resulting silicon carbide membrane permeate has the following ion content: Mg 2+ Content 0.005 mg / L, Ca 2+The concentration of sodium chloride was 0.005 mg / L, COD 320 mg / L, sodium sulfate 0.96 g / L, and sodium chloride 3 g / L. The permeate from the ceramic membrane was fed into a nanofiltration unit at an operating pressure of 3 MPa to obtain a sodium chloride solution. This sodium chloride solution was then fed into an ozone catalytic oxidation system with an ozone dosage of 0.4 g / L, resulting in a sodium chloride solution with the following ion concentration: Mg... 2+ Content 0.001 mg / L, Ca 2+ The concentration was 0 mg / L, COD 40 mg / L, sodium sulfate 0.02 g / L, and sodium chloride 3 g / L. The sodium chloride solution was concentrated via reverse osmosis, and the concentrate was then evaporated and crystallized to obtain industrial-grade sodium chloride salt with a purity of 98.1%. Example 3

[0078] After biochemical treatment, the glufosinate production wastewater contains 5 g / L NaCl and Mg. 2+ 0.01 g / L, Ca 2+ 0.01 g / L, COD 600 mg / L, Na₂SO₄ 1.1 g / L, TP 16 mg / L, filtered through a 50 nm ceramic membrane device at an operating pressure of 0.1 MPa and a cross-flow velocity of 0.15 m / s, the solids were removed. The resulting permeate from the ceramic membrane contained the following ion content: Mg 2+ Content 0.002 mg / L, Ca 2+ The composition is 0.002 mg / L, COD 390 mg / L, sodium sulfate 1.06 g / L, and sodium chloride 5 g / L. The permeate from the ceramic membrane is fed into a nanofiltration membrane at an operating pressure of 3.5 MPa to obtain a sodium chloride solution. This sodium chloride solution is then fed into an ozone catalytic oxidation system with an ozone dosage of 0.7 g / L, achieving a COD removal rate of 51% and yielding a sodium chloride solution with a COD of 49 ppm. The concentrate from the reverse osmosis concentration is then evaporated and crystallized to obtain industrial-grade sodium chloride salt with a purity of 98.3%.

[0079] In contrast, 1-2 wt% diatomaceous earth filter aid was added to the feed solution entering the ceramic membrane for filtration. The flux decay curve for the first 20 minutes is shown below. Figure 3 As shown, it can be seen that by adding a filter aid to the feed solution during the solids removal process, a filter cake layer can be formed on the surface of the membrane, thus avoiding membrane fouling.

Claims

1. A glufosinate wastewater resource recovery and reuse device, characterized in that, Includes the following steps: The reaction apparatus (1) is used to carry out a biochemical degradation reaction on glufosinate wastewater; A settling tank (2) is connected to the reaction device (1) and is used to settle the wastewater generated by the reaction device (1); A ceramic membrane (4) is connected to a sedimentation tank (2) and is used to filter the wastewater that has undergone sedimentation treatment in the sedimentation tank (2). Nanofiltration membrane (5) is connected to the permeate side of ceramic membrane (4) and is used to perform nanofiltration treatment on the permeate of ceramic membrane (4); An advanced oxidation device (6) is connected to the permeate side of the nanofiltration membrane (5) and is used to oxidize the permeate obtained from the nanofiltration membrane (5). A reverse osmosis membrane (7) is connected to an advanced oxidation device (6) for salt concentration treatment of the oxidized wastewater; Evaporator (8), connected to the retentive side of reverse osmosis membrane (7), is used to evaporate and crystallize the obtained salt concentrate to obtain NaCl salt.

2. The glufosinate wastewater resource recovery and reuse device according to claim 1, characterized in that, Also includes: The filter aid addition tank (3) is used to add filter aid to the sedimentation tank (2).

3. The glufosinate wastewater resource recovery and reuse device according to claim 1, characterized in that, The aforementioned reaction apparatus is an A / O system, A 2 One of the / O systems.

4. The glufosinate wastewater resource recovery and reuse device according to claim 1, characterized in that, The ceramic membrane (4) is configured as a single tube, a flat plate, or a multi-channel ceramic membrane.

5. The glufosinate wastewater resource recovery and reuse device according to claim 1, characterized in that, The ceramic membrane (4) has an average pore size of 0.002 μm to 1 μm, or a molecular weight cutoff of 10,000 to 5,000,000 Da.

6. The glufosinate wastewater resource recovery and reuse device according to claim 1, characterized in that, The ceramic film (4) is made of alumina, zirconium oxide, silicon carbide or titanium oxide.

7. The glufosinate wastewater resource recovery and reuse device according to claim 1, characterized in that, The advanced oxidation equipment (6) is an ozone oxidation equipment.

Images