Sodium thioglycolate-containing wastewater treatment device

Abstract

The utility model discloses a sodium thioglycolate-containing wastewater treatment device. A sodium thioglycolate-containing wastewater treatment system comprises a pretreatment tank, a centrifugal extraction device, a rectifying tower, a solvent feeding tank and a residual liquid neutralization tank, the pretreatment tank is used for mixing wastewater containing sodium thioglycolate with acid to form acidified wastewater; the centrifugal extraction device is used for carrying out centrifugal extraction treatment on the acidification wastewater; the rectifying tower is connected with a light phase outlet of the centrifugal extraction device; the solvent feeding tank is connected with a light phase feeding hole of the centrifugal extraction device; the top of the rectifying tower is connected with a solvent feeding tank; the residual liquid neutralization tank is connected with a heavy phase outlet of the centrifugal extraction device; according to the sodium thioglycolate-containing wastewater treatment system provided by the utility model, sodium thioglycolate is effectively separated and recycled, the resource utilization rate is improved, and the pollution to the environment is reduced.

Description

Technical Field

[0001] This utility model relates to the chemical industry, specifically to a wastewater treatment device containing sodium mercaptoacetate. Background Technology

[0002] Thioacetic acid is an organic compound containing thiol and acetic acid groups. It serves as an intermediate in pharmaceuticals such as phenalool and veterinary drugs like diclazuril. It can also be used as an antioxidant, catalyst, and in biochemical research. Its derivatives are used in depilatory agents, hair curling products, heat stabilizers in polyvinyl chloride processing, corrosion inhibitors in the petroleum industry, mineral processing aids, and intermediates in organic synthesis. During the production of thioacetic acid esters, a large amount of wastewater containing sodium thioacetate is generated, which contains sodium thioacetate and its sodium salts.

[0003] Existing technologies use conventional distillation to treat wastewater and separate sodium thioglycolate. However, this technology has several limitations, including: 1. Ineffective separation of sodium thioglycolate and its sodium salt; 2. The high oxidizability and strong corrosiveness of thioglycolate, requiring protective measures; and the safety risks associated with its corrosiveness; 3. Failure to achieve continuous production, impacting overall treatment efficiency.

[0004] Therefore, in order to solve the above-mentioned problems in the existing process for separating sodium thioglycolate from thiocyanate wastewater, a new wastewater treatment device containing sodium thioglycolate is needed. Utility Model Content

[0005] The purpose of this invention is to provide a wastewater treatment device containing sodium thioglycolate, to solve the aforementioned problems existing in the process of separating sodium thioglycolate from thiocyanate wastewater. This invention is achieved through the following technical solutions:

[0006] A wastewater treatment device containing sodium thioacetate includes:

[0007] Pretreatment tank T001 is used to mix wastewater containing sodium thioacetate with acid to form acidified wastewater; and to convert sodium thioacetate into an aqueous solution containing thioacetic acid.

[0008] Centrifugal extraction device 003 is used to centrifuge extract acidified wastewater; the centrifugal extraction device 003 includes a heavy phase inlet 31; the heavy phase inlet 31 is connected to the pretreatment tank T001.

[0009] Distillation column T010 is used to distill the light phase product output from the centrifugal extraction device to obtain thioglycolic acid product and extractant; the centrifugal extraction device 003 also includes a light phase outlet 34, and distillation column T010 is connected to the light phase outlet 34; the distillation column performs evaporation recovery of the solvent loaded with thioglycolic acid and concentration treatment of thioglycolic acid, realizing dual recovery of solvent and thioglycolic acid, and improving resource utilization efficiency.

[0010] Solvent feed tank T008 is used to input the extractant into the centrifugal extraction device 003; the centrifugal extraction device 003 also includes a light phase feed port 32, and the solvent feed tank T008 is connected to the light phase feed port 32; the top of the distillation column T010 is connected to the solvent feed tank T008, so that the extractant in the distillation column T010 enters the solvent feed tank T008.

[0011] The residual liquid neutralization tank T007 is used to neutralize the heavy phase product output from the centrifugal extraction device 003; the centrifugal extraction device 003 also includes a heavy phase outlet 33, and the residual liquid neutralization tank T007 is connected to the heavy phase outlet 33.

[0012] Optionally, the centrifugal extraction device 003 includes multiple centrifugal extractors connected in series in countercurrent. Using centrifugal extractors for multi-stage countercurrent extraction effectively extracts thioglycolic acid from the aqueous solution and separates it from a suitable solvent, achieving efficient recovery and utilization of thioglycolic acid.

[0013] Optionally, the centrifugal extraction device 003 is equipped with a protective gas inlet 35 and a protective gas outlet 36. The centrifugal extractor uses nitrogen as a protective gas, which effectively prevents the oxidation of mercaptoacetic acid, thereby improving recovery efficiency and product quality.

[0014] Optionally, the sodium mercaptoacetate wastewater treatment device further includes a condensation device 004, and the centrifugal extraction device 003 is connected to the condensation device 004; the condensation device 004 is used to condense the vaporized extractant gas output from the protective gas outlet 36. The condensation device prevents the extractant from being lost due to volatilization with the protective gas.

[0015] Optionally, the wastewater treatment device containing sodium mercaptoacetate further includes a condensation mixing tank T005, wherein the condensation device 004 is connected to the condensation mixing tank T005; the condensation mixing tank T005 is used to store the condensate generated in the condensation device.

[0016] Optionally, the sodium mercaptoacetate-containing wastewater treatment device further includes a stripping tower T006, which is connected to the residual liquid neutralization tank T007; the stripping tower T006 evaporates and recovers the extractant from the neutralized heavy phase product. By recovering the residual solvent through the stripping tower, solvent recycling is achieved, reducing resource waste and environmental pollution.

[0017] Optionally, the wastewater treatment device containing sodium mercaptoacetate further includes an acidification tank T002, which is located between the pretreatment tank T001 and the centrifugal extraction device 003.

[0018] Optionally, the wastewater treatment device containing sodium mercaptoacetate further includes a load collection tank T009, which is located between the centrifugal extraction device 003 and the distillation column T010.

[0019] Optionally, the extractant may be at least one of ethyl acetate, propyl acetate, and isopropyl acetate.

[0020] Optionally, the centrifugal extractor is a corrosion-resistant, fully composite hybrid material extractor. This avoids the safety risks associated with corrosion and improves the reliability and service life of the equipment.

[0021] Compared with existing technologies, the beneficial effects of this technical solution are as follows:

[0022] This invention employs a pretreatment tank, centrifugal extractor, neutralization treatment, and stripping tower in the design of a wastewater treatment system containing sodium thioacetate. This achieves effective separation and recovery of sodium thioacetate, resulting in higher treatment efficiency, lower environmental pollution, and higher resource utilization. Through the acidification process in the pretreatment tank, sodium thioacetate is converted into an aqueous solution containing thioacetic acid, achieving separation and treatment of sodium thioacetate in the wastewater and avoiding direct discharge of wastewater that would pollute the environment. The centrifugal extractor uses multi-stage countercurrent extraction to effectively extract thioacetic acid from the aqueous solution and separate it from a suitable solvent, achieving efficient recovery and utilization of thioacetic acid. The centrifugal extractor uses nitrogen as a protective gas to effectively prevent the oxidation of thioacetic acid, improving recovery efficiency and product quality. The centrifugal extractor uses fully composite hybrid materials, avoiding safety risks caused by corrosion and improving equipment reliability and service life. The stripping tower recovers residual solvent, achieving solvent recycling and reducing resource waste and environmental pollution. By evaporating and recovering the solvent loaded with mercaptoacetic acid and concentrating the mercaptoacetic acid, dual recovery of the solvent and mercaptoacetic acid is achieved, thereby improving resource utilization efficiency. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 Here is a schematic diagram of the device of this utility model:

[0025] The diagram is labeled as follows: Pretreatment tank T001, Acidification liquid tank T002, Centrifugal extraction device T003, Condensation device T004, Condensation mixture tank T005, Solvent feed tank T008, Residual liquid neutralization tank T007, Stripping tower T006, Load collection tank T009, Distillation tower T010, Heavy phase feed inlet 31, Light phase feed inlet 32, Heavy phase outlet 33, Light phase outlet 34, Protective gas inlet 35, Protective gas outlet 36. Detailed Implementation

[0026] Various exemplary embodiments of the present invention are now described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention. It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the present invention.

[0027] Furthermore, regarding the numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, are also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0028] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art described herein. While only preferred methods and materials are described herein, any methods and materials similar to or equivalent to those described herein may be used in the implementation or testing of this invention.

[0029] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0030] like Figure 1 The device shown is a wastewater treatment device containing sodium thioacetate, comprising:

[0031] Pretreatment tank T001 is used to mix wastewater containing sodium thioglycolate with acid to form acidified wastewater;

[0032] Centrifugal extraction device 003 is used to treat acidified wastewater by centrifugal extraction. The centrifugal extraction device includes a heavy phase inlet 31, a light phase inlet 32, a heavy phase outlet 33, and a light phase outlet 34. The heavy phase inlet 31 is connected to a pretreatment tank T001; an acidified liquid tank T002 is provided between the pretreatment tank T001 and the centrifugal extraction device 003.

[0033] like Figure 1 As shown, in some embodiments, the centrifugal extraction device 003 includes multiple centrifugal extractors connected in series in countercurrent. All centrifugal extractors utilize fully composite hybrid materials.

[0034] Distillation column T010 is connected to the light phase outlet 34 of centrifugal extraction device 003. Distillation column T010 is used to distill the light phase product output from centrifugal extraction device 003 to obtain mercaptoacetic acid product and extractant. A load collection tank T009 is provided between centrifugal extraction device 003 and distillation column T010.

[0035] Solvent feed tank T008 is connected to the light phase feed port 32 of centrifugal extraction device 003. Solvent feed tank T008 is used to input extractant into centrifugal extraction device 003. The top of distillation column T010 is connected to solvent feed tank T008, so that the extractant in distillation column T010 enters solvent feed tank T008.

[0036] The residual liquid neutralization tank T007 is connected to the heavy phase outlet 33 of the centrifugal extraction device 003. The residual liquid neutralization tank T007 is used to neutralize the heavy phase product output from the centrifugal extraction device 003. The residual liquid neutralization tank T007 is connected to a stripping tower T006, which evaporates and recovers the extractant from the neutralized heavy phase product. The recovered extractant is sent to a condensate mixing tank T005.

[0037] The centrifugal extraction apparatus 003 is equipped with a protective gas inlet 35 and a protective gas outlet 36, used to prevent the oxidation of thioglycolic acid by introducing a protective gas into the centrifugal extraction apparatus 003 during the extraction process. Nitrogen gas is used as the protective gas. A condenser 004 is connected to the protective gas outlet 36. Figure 1As shown, the condensing device 004 includes three condensing tanks, which condense the protective gas output from the protective gas outlet 36. The condensing device 004 is connected to a condensate mixture tank T005, which stores the condensate generated in the condensing device. For example, the protective gas inlet 35 is located at the top of the centrifugal extractor. It should be noted that the protective gas inlet 35 and the protective gas outlet 36 can be located on the same side of the centrifugal extractor.

[0038] The operation procedure for treating sulfuric acid ester wastewater using the above system is as follows:

[0039] Step 1. The wastewater containing sodium thioacetate is introduced into a pretreatment tank and acidified by contacting hydrochloric acid to obtain an aqueous solution containing thioacetic acid. The pH of the acidified wastewater is 1-3.

[0040] Step 2. Pour the aqueous solution containing mercaptoacetic acid into the acidification tank and connect it to the feed port of the centrifugal extractor.

[0041] Step 3. In a centrifugal extractor, countercurrent extraction is performed using ethyl acetate and an aqueous solution containing mercaptoacetic acid in multiple stages, and the material and solvent are completely separated by centrifugal force. The volume ratio of solvent to acidified wastewater is 0.5-1.5:1.

[0042] Step 4. The extracted heavy phase product is introduced into the residual liquid neutralization tank, neutralized with sodium hydroxide to pH 6-7, and then sent to the stripping tower for solvent recovery.

[0043] Step 5. In the stripping tower, the remaining liquid after neutralization is stripped to recover the residual solvent, and the recovered solvent is returned to the solvent feed tank.

[0044] Step 6. The extracted mercaptoacetic acid extract is first fed into a loading collection tank, and then into a distillation column. The light phase product output from the distillation column centrifugal extraction device yields mercaptoacetic acid product and extractant. The extractant enters the solvent feed tank and is then fed into a centrifugal extractor.

[0045] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A wastewater treatment device containing sodium mercaptoacetate, characterized in that, include The pretreatment tank (T001) is used to mix wastewater containing sodium thioacetate with acid to form acidified wastewater; A centrifugal extraction device (003) is used to centrifuge and extract acidified wastewater; the centrifugal extraction device (003) includes a heavy phase inlet (31); the heavy phase inlet (31) is connected to the pretreatment tank (T001); A distillation column (T010) is used to distill the light phase product output from the centrifugal extraction device to obtain mercaptoacetic acid product and extractant; the centrifugal extraction device (003) also includes a light phase outlet (34), and the distillation column (T010) is connected to the light phase outlet (34); A solvent feed tank (T008) is used to input the extractant into the centrifugal extraction device (003); the centrifugal extraction device (003) also includes a light phase feed port (32), and the solvent feed tank (T008) is connected to the light phase feed port (32); the top of the distillation column (T010) is connected to the solvent feed tank (T008) so that the extractant in the distillation column (T010) enters the solvent feed tank (T008); The residual liquid neutralization tank (T007) is used to neutralize the heavy phase product output from the centrifugal extraction device (003); the centrifugal extraction device (003) also includes a heavy phase outlet (33), and the residual liquid neutralization tank (T007) is connected to the heavy phase outlet (33).

2. The wastewater treatment device containing sodium mercaptoacetate according to claim 1, characterized in that, The centrifugal extraction device (003) includes multiple centrifugal extractors connected in series in countercurrent.

3. The wastewater treatment device containing sodium mercaptoacetate according to claim 1, characterized in that, The centrifugal extraction device (003) is provided with a protective gas inlet (35) and a protective gas outlet (36).

4. The wastewater treatment device containing sodium mercaptoacetate according to claim 3, characterized in that, The sodium mercaptoacetate wastewater treatment device further includes a condensation device (004), and the centrifugal extraction device (003) is connected to the condensation device (004); the condensation device (004) is used to condense the vaporized extractant gas output from the protective gas outlet (36).

5. The wastewater treatment device containing sodium mercaptoacetate according to claim 4, characterized in that, The sodium mercaptoacetate wastewater treatment device further includes a condensation mixing tank (T005), and the condensation device (004) is connected to the condensation mixing tank (T005); the condensation mixing tank (T005) is used to store the condensate generated in the condensation device.

6. The wastewater treatment device containing sodium mercaptoacetate according to claim 5, characterized in that, The sodium mercaptoacetate wastewater treatment device further includes a stripping tower (T006), which is connected to the residual liquid neutralization tank (T007); the stripping tower (T006) evaporates and recovers the extractant from the neutralized heavy phase product.

7. The wastewater treatment device containing sodium mercaptoacetate according to claim 1, characterized in that, The sodium mercaptoacetate wastewater treatment device also includes an acidification tank (T002), which is located between the pretreatment tank (T001) and the centrifugal extraction device (003).

8. The wastewater treatment device containing sodium mercaptoacetate according to claim 1, characterized in that, The sodium mercaptoacetate wastewater treatment device also includes a load collection tank (T009), which is located between the centrifugal extraction device (003) and the distillation column (T010).

9. The wastewater treatment device containing sodium mercaptoacetate according to claim 2, characterized in that, The centrifugal extractor is a corrosion-resistant, fully composite hybrid material extractor.

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