SU924055A1 - Method for controlling process for purifying solvent from impurities - Google Patents

Description

The invention relates to the automation of polymerization processes, in particular to a method for regulating the process of purification of the solvent from impurities, and can be used in the production of synthetic rubber.

A known method of regulating the process of purification of the solvent from impurities used in a solution polymerization by azeotropic drying by changing the steam consumption in the boiler of the azeotropic drying column, processing the organoaluminum compounds with a polymerization catalyst, or its component [1

However, this method does not provide obtaining a solvent with a given degree of purification from impurities, since the costs of steam, an organoaluminum compound in it do not depend on the concentration of total impurities in the solvent.

2

The closest to the proposed method is to regulate the process of purification of the solvent from impurities in the process of polymerization of diene hydrocarbons by azeotropic drying by changing the steam consumption in the boiler of the azeotropic drying column equipped with a boiler, bypassing the dried solvent stream into which the organometallic compound is introduced [2]

However, in the known method, the accuracy of the stabilization of the concentration of impurities in the dried solvent decreases because of the low accuracy of the measurement of the small consumption of the solution of the organo-aluminum compound, and also because of the large retardation time in the control channels.

The purpose of the invention is to improve the accuracy of stabilization of the concentration of impurities in the dried solvent.

This goal is achieved by

that in the method of regulating ppoies3

92 * 4055

BUT

sa purification from impurities in the solvent during the polymerization of diene hydrocarbons by azeotropic dehydration change steam flow to the reboiler of the column an azeotropic osush- ₅ ki equipped kettle, dried bypass flow of solvent into which the organometallic compound is stabilized costs baypasiruemogo stream carried th cervical solvent and organometallic compounds, change the flow rate of the vapor phase from the azeotropic drying column, depending on the concentration in the bypass stream, metal anicheskogo compound, wherein the flow of the vapor phase from the azeotropic dehydration column is stabilized change steam flow to the reboiler of the column an azeotropic dehydration.

In this case, if the vapor phase consumption from the azeotropic drying column or the steam flow rate into the boiler of the azeotropic drying column exceeds the maximum permissible value, the load on the azeotropic drying column * is reduced, and an organoaluminum compound or lithium butyl is used as the organometallic compound. ,

The drawing shows a block diagram of the regulatory system.

Returnable solvent is fed to the column 1 azeotropic drying and stabilized by the regulator 2, receiving information about the flow from the sensor 3 and acting on the control valve Steam flow in the boiler 5 of the column 1 azeotropic drying is stabilized by the regulator 6,

I

receiving information about the flow from the sensor 7 and acting on the valve 8.

The dried solvent stream is bypassed through conduit 9 and its flow is stabilized by regulator 10, receiving information about flow from sensor 11 and acting on valve 12. Pipeline 9 introduces an organo-aluminum compound or lithium butyl in a rater, whose flow is stabilized by regulator 13, receiving flow information from the sensor 1 * 4 and acting on the valve 15 · Behind the entry point of aluminum organic compound or lithium butyl in line 9 is installed a sensor 15 of the concentration of this compound, which supplies this the information on the regulator 17, which stabilizes this value by changing the flow rate (distillation) of the vapor phase from column 1, i.e. by changing the reference to the vapor flow controller (distillation) 18, receiving information about the flow rate from sensor 19 · The vapor flow (distillation) stabilization is performed by changing the steam flow rate to the boiler 5 of column 1, and thus the regulator 18 changes the steam regulator 6 task.

If the concentration of the organoaluminum compound or lithium butyl in the bypass stream is exceeded, the flow rate (distillation) of the vapor phase from column 1 is reduced and vice versa. At the same time, steam consumption decreases and increases accordingly.

When the flow rate (distillation) of the vapor phase from the column 1 of a given maximum permissible value is exceeded, the controller 18 reduces the load on the column 1 of azeotropic drying, reducing the task to the controller 2.

Using the proposed method allows to increase the accuracy of stabilization of the concentration of impurities in the dried solvent and, consequently, reduce their content, which leads to a decrease in catalyst consumption during the polymerization process and to an increase in the quality of commercial polymer.

Claims (3)

Claim 1. The method of regulating the process of purification of the solvent from impurities in the process of polymerization of diene hydrocarbons by azeotropic drying by changing the steam flow rate in the boiler of the azeotropic drying column equipped with a boiler, bypassing the dried solvent stream into which the organometallic compound is introduced, in order to improve the accuracy stabilizing the concentration of impurities in the solvent, stabilize the costs of the bypass flow of the dried solvent and the organometallic compound, change the flow rate of the vapor phase from the azeotropic drying column depending on the concentration in the bypassed flow of the organometallic compound, and the flow rate of the vapor phase from the boiler is 924055 6 Lines of azeotropic drying are stabilized by changing the steam consumption in the boiler of azeotropic drying column. 2. The method according to claim 1, characterized in that when the vapor phase flow from the azeotropic drying column or the steam flow to the boiler of the azeotropic drying column exceeds the maximum permissible value, the load on the azeotropic drying column is reduced. 3. The method according to claim 1, characterized in that an organoaluminum compound or lithium butyl is used as the organometallic compound. five