Wastewater recovery treatment system for butyl acrylate production process

Abstract

The utility model discloses a wastewater recovery treatment system for a butyl acrylate production process, which is characterized in that an esterification reaction wastewater tank is connected to an alcohol recovery device, the alcohol recovery device is connected to a neutralization system, and the neutralization system is connected with a multi-effect evaporation device. The butanol raw material is saved, and the production cost is reduced; the neutralization system is connected with the alcohol recovery device, part of wastewater generated in the alcohol recovery reaction is used for the neutralization reaction, the wastewater treatment process is optimized, the multiple-effect evaporation device is connected behind the neutralization system, salt in the wastewater is evaporated and precipitated, the salt content and the COD value of the wastewater are greatly reduced, and the wastewater treatment efficiency is improved. And meanwhile, a large amount of industrial salt in the wastewater is purified and recycled, so that a certain economic value is generated.

Description

Technical Field

[0001] The utility model relates to the technical field of butyl acrylate production, in particular to a butyl acrylate production wastewater recovery and treatment system. Background Art

[0002] Butyl acrylate can be produced by the process of recombinant decomposition of acrylic acid esters. During the esterification reaction, a large amount of wastewater is generated. The wastewater consists of approximately 5-10% water, 70-80% butanol, and 15-25% butyl acrylate. This wastewater still has high economic value and needs to be recovered and treated. The existing treatment method is to recover the butanol and use it as a reactant in the esterification reaction, while the remaining wastewater is simply neutralized.

[0003] The wastewater produced by the neutralization reaction contains about 30,000 mg / L of salt and about 6-9% butanol; the wastewater produced by alcohol recovery contains about 1-2% butanol, a COD value of about 20,000 mg / L, and a salt content of about 30,000 mg / L. The above wastewater is far from meeting the standards for direct discharge. Currently, many companies do not pay attention to it as the end-of-production line system. In addition, there is a large amount of industrial salt in the neutralization wastewater that can be recycled and has certain economic value. Summary of the Invention

[0004] The purpose of this utility model is to propose an efficient butyl acrylate production wastewater recovery and treatment system, which can more efficiently realize alcohol recovery, further optimize the wastewater neutralization treatment process, so that the wastewater from the butyl acrylate production process can ultimately meet the direct discharge standard, and at the same time purify a large amount of industrial salt in the wastewater to create economic value.

[0005] To achieve the above-mentioned purpose, the technical solution provided by the present invention is: a butyl acrylate production wastewater recovery and treatment system, comprising an alcohol recovery device, a neutralization system and a multiple-effect evaporation device, wherein the alcohol recovery device is connected to the neutralization system, and the neutralization system is connected to the multiple-effect evaporation device.

[0006] In order to achieve more efficient alcohol recovery, the technical solution provided by the utility model includes: providing an alcohol recovery device, which includes: an alcohol recovery kettle, a stripping tower, a condenser, a distillation tower, and a first wastewater temporary storage tank connected in sequence, wherein the stripping tower and the distillation tower are also connected to a venting trap, and the condenser is also separately connected to the first wastewater temporary storage tank;

[0007] Furthermore, the distillation column is also connected to a product tank;

[0008] Furthermore, the distillation tower is also connected back to the esterification reaction stage.

[0009] In order to optimize the neutralization treatment process of wastewater, the technical solution provided by the utility model includes: setting up a neutralization system, which includes: an alkali adjustment reaction tank, an alkali adjustment buffer tank, a neutralization reactor, a high-efficiency phase separator, and a second wastewater storage tank connected in sequence, and the high-efficiency phase separator is also connected to an incinerator.

[0010] In order to enable the neutralized wastewater to meet the direct discharge standard, the technical solution provided by the utility model includes: adding a multi-effect evaporation device, which is connected to the neutralization system;

[0011] Furthermore, the multiple-effect evaporation device includes a pH adjustment reactor;

[0012] Furthermore, the multiple-effect evaporation device also includes a pH adjustment buffer tank;

[0013] Furthermore, the multiple-effect evaporation device further includes a decarbonization tower;

[0014] Furthermore, the multiple-effect evaporation device includes a desalination unit.

[0015] The advantages and beneficial effects of the utility model are as follows: by adopting the alcohol recovery device, the butanol in the esterification reaction wastewater can be reused, thereby saving butanol raw materials and reducing production costs; by adopting the neutralization system connected to the alcohol recovery device, part of the wastewater generated by the alcohol recovery reaction is utilized for the neutralization reaction, thereby optimizing the wastewater treatment process; by connecting a multi-effect evaporation device after the neutralization system, the salt in the wastewater is evaporated and precipitated, thereby greatly reducing the salt content and COD value of the wastewater, and can meet the production standard for direct discharge; at the same time, a large amount of industrial salt in the wastewater is purified and recovered, thereby generating certain economic value. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of a butyl acrylate production wastewater recovery and treatment system proposed by the utility model;

[0017] Figure 2 This is a schematic diagram of an alcohol recovery device for a butyl acrylate production process proposed by the present invention;

[0018] Figure 3 This is a schematic diagram of a neutralization system for a butyl acrylate production process proposed in the present invention;

[0019] Figure 4 This is a schematic diagram of a multi-effect evaporation device for a butyl acrylate production process proposed in the present invention;

[0020] Figure numerals: 1-esterification reaction wastewater tank, 2-alcohol recovery device, 21-alcohol recovery kettle, 22-stripping tower, 23-condenser, 24-distillation tower, 25-first wastewater temporary storage tank, 26-venting trap, 3-neutralization system, 31-alkali adjustment reaction tank, 32-alkali adjustment buffer tank, 33-neutralization reactor, 34-high-efficiency phase separator, 35-second wastewater temporary storage tank, 36-incinerator, 4-multi-effect evaporation device, 41-mixer, 42-acid adjustment reactor, 43-acid adjustment buffer tank, 44-decarbonization tower, 45-alkali adjustment reactor, 46-alkali adjustment buffer tank, 47-first effect evaporation, 48-second effect evaporation, 49-third effect evaporation, 410-desalting unit, 411-condensate tank, 5-wastewater discharge area, 6-esterification reaction stage, 7-product tank. DETAILED DESCRIPTION

[0021] The following embodiments are used to further describe the specific embodiments of the present invention in conjunction with the accompanying drawings and examples. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Example

[0022] A butyl acrylate production wastewater recovery and treatment system comprises an alcohol recovery device 2 and a neutralization system 3, wherein the alcohol recovery device 2 is connected to the neutralization system 3, the multi-effect evaporation device 4 is connected to the neutralization system 3, and the esterification reaction wastewater tank 1 is connected to the alcohol recovery device 2. Wastewater from the alcohol recovery device 2 and the multi-effect evaporation device 4 is discharged to a wastewater discharge area 5 through a pipeline.

[0023] The alcohol recovery device 2 includes: an alcohol recovery kettle 21, a stripping tower 22, a condenser 23, a distillation tower 24, and a first wastewater temporary storage tank 25 connected in sequence. The stripping tower 22 and the distillation tower 24 are also commonly connected to a venting trap 26, and the condenser 23 is also separately connected to the first wastewater temporary storage tank 25.

[0024] The neutralization system 3 includes: an alkali adjustment reaction tank 31, an alkali adjustment buffer tank 32, a neutralization reactor 33, a high-efficiency phase separator 34, and a second wastewater temporary storage tank 35, which are connected in sequence. The high-efficiency phase separator is also connected to an incinerator 36.

[0025] The multi-effect evaporation device 4 is sequentially connected with a mixer 41, an acid adjustment reactor 42, an acid adjustment buffer tank 43, a decarbonization tower 44, an alkali adjustment reactor 45, an alkali adjustment buffer tank 46, a first-effect evaporation 47, a second-effect evaporation 48, a third-effect evaporation 49, a desalination unit 410, and a condensation tank 411.

[0026] The wastewater from the esterification reaction is first stored in the esterification reaction wastewater tank 1 and then transferred to the alcohol recovery device 2 via a pipeline for separation and purification of the alcohol. Specifically, the esterification reaction wastewater first enters the alcohol recovery kettle 21, where a large amount of butanol and a small amount of oil and water are heated and evaporated, and then enter the stripping tower 22 for separation. The mixed solution of the solute butanol and a small amount of butyl acrylate obtained from the rough separation in the stripping tower 22 and the solvent enter the condenser 23 in sequence, and the discharged waste gas enters the vent trap 26. After the solvent is condensed, it directly enters the first wastewater temporary storage tank 25. The butanol and butyl acrylate are condensed and enter the distillation tower 24 for further separation. The separated butanol flows through a pipeline to the esterification reaction stage 6, the separated butyl acrylate flows through a pipeline to the product tank 7, and the distillation wastewater flows to the first wastewater temporary storage tank 25.

[0027] The separated alcohol is used as a reactant to continue to participate in the esterification reaction 6. Part of the wastewater generated by the alcohol recovery device 2 enters the neutralization system 3. The wastewater that meets the emission standards is directly discharged into the wastewater discharge area 5. The neutralization system 3 performs the first step of treatment on the wastewater, and then transfers it to the multi-effect evaporation device 4 for further treatment. The treated wastewater is discharged into the wastewater discharge area 5.

[0028] After the neutralization system 3 absorbs a small amount of wastewater from the alcohol recovery device 2, its pH is still relatively high. It needs to be adjusted to less than 8 in the alkali adjustment reaction tank 31, and then temporarily stored in the alkali adjustment buffer tank 32. It enters the neutralization reactor 33 to adjust the pH to neutral, and then enters the high-efficiency phase separator 34. The high-efficiency phase separator 34 flows the oil phase formed by the saponification reaction of alkali and oil to the incinerator 8, and the remaining water phase containing a large amount of salt enters the second wastewater temporary storage tank 35.

[0029] The treatment process of the multi-effect evaporation device 4 is as follows: first, the wastewater in the second wastewater temporary storage tank 35 enters the mixer 41, is mixed with concentrated sulfuric acid, and then transferred to the acid adjustment reactor 42. After the adjustment is completed, the wastewater enters the acid adjustment buffer tank 43, and then is transferred to the decarbonization tower 44. After decarbonization, it enters the alkali adjustment reactor 45 to adjust the pH. After completion, it enters the alkali adjustment buffer tank 46. The wastewater in the alkali adjustment buffer tank directly enters the multi-effect evaporation device. After the multi-effect evaporation treatment, it is desalinated by the desalination unit 410. Finally, the condensate tank 411 collects the treated wastewater and discharges it into the wastewater discharge area 5.

[0030] After treatment in alcohol recovery unit 2, the COD value of the wastewater generated by the esterification reaction is reduced to below 5000, and the pH of the wastewater is neutral, allowing it to partially replace the water used in neutralization system 3. After treatment in multi-effect evaporation unit 4, the neutralized wastewater has a salt content of approximately 200-300 mg / L and a COD value of less than 100 mg / L, allowing it to be directly discharged to wastewater discharge area 5.

[0031] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, making several improvements and modifications without departing from the technical principles of the present invention should also be regarded as within the scope of protection of the present invention.

Claims

1. A wastewater recovery and treatment system for a butyl acrylate production process, comprising an alcohol recovery unit and a neutralization system; The alcohol recovery device includes: an alcohol recovery kettle, a stripping tower, a condenser, a distillation tower, and a first wastewater temporary storage tank connected in sequence. The stripping tower and the distillation tower are also connected to a venting trap, and the condenser is also connected to the first wastewater temporary storage tank separately. The neutralization system includes: an alkali adjustment reaction tank, an alkali adjustment buffer tank, a neutralization reactor, a high-efficiency phase separator, and a second wastewater temporary storage tank, which are connected in sequence. The high-efficiency phase separator is also connected to an incinerator; Its characteristics are: The alcohol recovery device is connected to the neutralization system, and a multi-effect evaporation device is also provided. The multi-effect evaporation device is connected to the neutralization system.

2. The wastewater recovery and treatment system for the butyl acrylate production process according to claim 1, characterized in that: The multiple-effect evaporation device includes a pH adjustment reactor.

3. The wastewater recovery and treatment system for the butyl acrylate production process according to claim 1, characterized in that: The multiple-effect evaporation device includes a pH adjustment buffer tank.

4. The wastewater recovery and treatment system for the butyl acrylate production process according to claim 1, characterized in that: The multi-effect evaporation device includes a decarbonization tower.

5. The wastewater recovery and treatment system for the butyl acrylate production process according to claim 1, characterized in that: The multiple-effect evaporation device includes a desalination unit.

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