CN-121974780-A - Method for extracting neopentyl glycol from wastewater

Abstract

The invention provides a method for extracting neopentyl glycol from wastewater, wherein the wastewater is from wastewater generated at the top of a neopentyl glycol light removal tower, the content of neopentyl glycol in the wastewater is about 10-15%, the generated wastewater directly enters a stripping tower, pall ring filler is arranged in the stripping tower, the neopentyl glycol in the wastewater is purified by improving the feeding position, 65-75% of neopentyl glycol aqueous solution is produced at the bottom of the tower, clear liquid containing methanol and isobutyraldehyde is discharged from the top of the tower, the neopentyl glycol in the wastewater is separated under the pressure of 10-20kPa and the temperature of 90-100 ℃, and the recovered neopentyl glycol aqueous solution directly enters the light removal tower through returning materials. The method can effectively recycle the neopentyl glycol in the wastewater, reduce the production cost and increase the production benefit.

Inventors

• LI YANSHUN
• SUN ZHAOJIAN
• WANG MINGJI
• LU XIAO
• SU SHENGYI

Assignees

• 聊城鲁西多元醇新材料科技有限公司

Dates

Publication Date

20260505

Application Date

20251226

Claims (10)

1. 1. A method for extracting neopentyl glycol from wastewater is characterized by comprising the steps of separating wastewater after the wastewater enters a stripping tower, purifying the neopentyl glycol in the wastewater by improving a feeding position, generating a small amount of clear liquid at the top of the tower, generating 65-75% of neopentyl glycol aqueous solution at the bottom of the tower, directly entering a light component removing tower through returning materials, and filling the stripping tower with filler.
2. 2. The method for extracting neopentyl glycol from wastewater of claim 1, wherein the neopentyl glycol content in the wastewater is 10-15%.
3. 3. The process for the extraction of neopentyl glycol from a wastewater of claim 1, wherein the stripper packing is pall ring packing.
4. 4. The process for the extraction of neopentyl glycol from waste water according to claim 1, characterized in that the pressure in the stripping column is 10-20kpa and the bottom temperature is 90-100 ℃.
5. 5. The process for the extraction of neopentyl glycol from a wastewater of claim 1, wherein the ratio of the feed position of the stripper to the height of the stripper is 1.5:10.5.
6. 6. An apparatus for extracting neopentyl glycol from wastewater is characterized by comprising a light component removing tower (2) and a stripping tower (9) which are communicated, wherein a reflux drum (4) of the light component removing tower is partially conveyed to the light component removing tower (2) through a pump (3), and a part of reflux drum is conveyed to the stripping tower (9).
7. 7. The plant for the extraction of neopentyl glycol from wastewater according to claim 6, characterized in that the flow (14) is set by means of a conduit between the pump (3) and the stripper (9) of the light ends column (2).
8. 8. Device for extracting neopentyl glycol from waste water according to claim 7, characterized in that a pump (13) is arranged in sequence between the stripping tower bottom (9) and the light ends removal tower (2), and the light ends removal tower feeding flowmeter (1) is positioned between a regulating valve (15) at the outlet of the pump (13) and the light ends removal tower (2).
9. 9. The device for extracting neopentyl glycol from wastewater according to claim 8, characterized in that a lightness-removing column reflux pump (3) and a stripper feeding flowmeter (14) are arranged between the lightness-removing column (2) and the stripper (9) in sequence.
10. 10. The device for extracting neopentyl glycol from wastewater according to claim 8, wherein the top of the stripping tower (9) is connected with a stripping tower reflux tank (10) through a stripping tower reflux pump (11) and is refluxed through a stripping tower top cooler (8), and the middle part of the stripping tower (9) is connected with a stripping tower reflux extraction (12).

Description

Method for extracting neopentyl glycol from wastewater Technical Field The utility model belongs to the technical field of neopentyl glycol production, and relates to a method for extracting neopentyl glycol from wastewater. Background Neopentyl glycol is a white crystalline solid with hygroscopicity, and is mainly used for producing unsaturated resins, oil-free alkyd resins, plasticizers, surfactants and the like of polyurethane foam plastics and elastomers, and the application is wide. The crude neopentyl glycol solution produced in the neopentyl glycol production process can be subjected to impurity removal through a light component removal tower and a heavy component removal tower to obtain a neopentyl glycol aqueous solution, and then further processing is carried out to obtain a neopentyl glycol product. The wastewater produced at the top of the light component removal tower contains 10-15% of neopentyl glycol, if the reflux of the light component removal tower is increased, the acid value at the bottom of the light component removal tower is increased, and if the reflux is reduced, the neopentyl glycol content in the wastewater is increased, so that the resource waste is caused. Disclosure of Invention The novel purpose is to provide a method for extracting neopentyl glycol from wastewater, so as to solve the problem of entrained neopentyl glycol in the wastewater of the existing production method. In order to achieve the above purpose, the present invention adopts the following technical scheme: The invention provides a method for extracting neopentyl glycol from wastewater, which comprises the steps of directly feeding the wastewater produced at the top of a light component removal tower into a stripping tower for stripping, wherein the content of the neopentyl glycol in the wastewater is 10-15%, filler in the stripping tower is pall ring filler, and the feeding position of the stripping tower is the proportion of the whole tower height to be 1.5-10.5. Preferably, the neopentyl glycol content in the wastewater produced by the light component removal tower is 10-15%. Preferably, the packing of the stripping tower is pall ring packing. Preferably, the pressure in the stripping column is between 10 and 20kpa. Preferably, the stripping column is fed at a location ratio of 1.5 to 10.5. The invention provides a device for extracting neopentyl glycol from wastewater, which comprises a light component removing tower and a stripping tower which are communicated, wherein the light component removing tower is conveyed to the stripping tower through the same pipeline and a pump. Preferably, a stripper feeding flowmeter is arranged between the light component removing tower and the stripper. Preferably, a stripping tower bottom pump, a regulating valve and a flowmeter are sequentially arranged between the stripping tower and the light component removal tower feeding, and the light component removal tower feeding flowmeter is positioned behind the returning regulating valve. Preferably, the top of the stripping tower is connected with a stripping tower reflux tank through a stripping tower reflux pump, and is refluxed by a cooler at the top of the stripping tower, and the middle part of the stripping tower is connected with the stripping tower for reflux extraction. Preferably, the temperature of the stripping tower kettle is controlled to be 90-100 ℃. The invention has the following beneficial effects: (1) After entering the stripping tower, the reflux and the extraction flow of the stripping tower are regulated, and the concentration of neopentyl glycol at the bottom of the stripping tower is regulated to be controlled between 65 and 75 percent. (2) At the pressure of 10-20kPa and the temperature of 90-100 ℃, the neopentyl glycol in the wastewater is separated by pall rings in a stripping tower, and finally, 65-75% neopentyl glycol aqueous solution is produced at the bottom of the tower. (3) The method and the system can effectively reduce the external discharge, improve the recovery rate of the neopentyl glycol, reduce the production cost and increase the production benefit. Drawings FIG. 1 is a schematic diagram of a system for improving the purity of neopentyl glycol product according to an embodiment of the present invention; The symbols represent: 1-light ends column feeding flow, 2-light ends column, 3-light ends column reflux pump, 4-light ends column reflux tank, 5-light ends column cooler, 6-light ends column bottom extraction, 7-light ends column bottom pump, 8-stripping column top cooler, 9-stripping column, 10-stripping column reflux tank, 11-stripping column reflux pump, 12-stripping column reflux extraction, 13-stripping column bottom pump, 14-stripping column feeding flowmeter, 15-light ends column reflux regulating valve. Detailed Description The invention provides a method for extracting neopentyl glycol from wastewater, which comprises the steps that wastewater produced at the top of a light