SU973141A1 - Device for automatic regulation of extractive rectification process - Google Patents

Description

(5) DEVICE FOR AUTOMATIC REGULATION BY THE EXTRACTIVE RECTIFICATION PROCESS

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The invention relates to devices for the automatic regulation of the process of multicomponent extractive distillation and can be used in the chemical, petrochemical and other industries.

A device for optimal control of a distillation column is known, which contains a raw material temperature controller connected to a sensor and a coolant supply valve, a computing unit associated with temperature sensors, a composition and consumption of raw materials, an optimizer whose inputs are js connected to a computing unit, and sensors cube temperatures, reflux and distillate flow rates, one of the optimizer outputs is connected to the raw material temperature controller, and the other outputs are connected via a dynamic filter to the master inputs of the flow regulators reflux, distillate consumption and temperature regulator of the cube of the column С 1

The closest to the technical essence of the invention is a device for automatic regulation of the extractive distillation process, comprising a sensor and a flow controller of the distillate, a sensor and a regulator of the flow of heat carrier into the cube of the column, pressure sensors of the cube and the top of the column block 2j.

The known device is characterized by insufficient compensation of disturbances that cause flooding of the column, leading to a deterioration in the quality of the separation products.

The aim of the invention is to increase the stability of the operation of the column and the quality of the distillate and bottom product.

The goal is achieved by additionally inserting a sensor and a flow controller, antifoam agent, a pressure sensor on the upper control plate, a raw material consumption sensor, matching and correcting blocks. In this case, the matching unit is connected by its inputs with the output of the correction unit and the computing unit, the input is connected with the master input of the flow controller of the defoamer, and the inputs of the correction unit are connected with the flow sensor and the pressure sensor on the upper control plate, the logic unit connected Svsimi inputs with pressure sensors of the cube and the top of the column. The computational unit is connected with its inputs (concentration sensors on the bottom and upper control plates, the logic unit, and outputs - with the master inputs of the distillate flow control and heat flow regulator to the cube of the column and matching unit. The drawing shows the block diagram of the device for automatic control. The device for automatic control by the process of extractive distillation in column 1 includes a distillate flow sensor 2, a regulator 3, a valve, and a heat carrier flow sensor 5 in a cube of columns , regulator 6 and valve 7, defoamer flow sensor 8, Si regulator valve 10. In addition, the bft cTBO device contains a sensor 11 for raw material consumption per column 1, pressure sensors cube 12 and the top of column 13, pressure sensor 14 on the upper control plate, impurity concentration sensors on the bottom 15 and top 1b control plates, logic block 17, connected by its inputs to sensors 12 and 13, corrective block 18, connected by its inputs to sensors 11 and 14, and logic block 17, computing unit 19, connected its inputs with sensors 15 and 16 and block 17, outputs which are connected to the driver inputs of the regulators 3 and 6, the matching unit 20 connected by its inputs with the correction unit 18 and the computing unit 19, the output of which is connected to the driver input of the controller 9. The device operates as follows. The logic block 17 calculates the value of the differential pressure over the column and compares it with a predetermined value — the maximum allowable value of the ARR, adh, determined by 10) ”1 column flooding. If the pressure drop is greater than the specified value, then the output is generated. Computing unit 19, which, in this case, calculates new values for the costs of distillate, heat carrier and defoamer. D.-. + AD C. .., where D4, 0,.,., 0t, VV hi the current values of the distillate, heat carrier and defoamer flow rates correspond to, and DO are constant values; - pressure drop across: column. From the computational unit, signals are sent to the controllers 3.6 and, through the matching unit 20, to the controller 9 in order to eliminate the flooding of the column. If the pressure drop value is less than the specified value, then logic block 17 outputs a signal to correction block 18, and the output from logic block 17 to computing block 19 becomes 0. At that, computing block 19 shows current concentrations of impurities on the control plates from sensors 15 and 16 calculates the flow rates of the distillate and the heat and coolant, which ensure the maintenance of the specified concentration values on the control plates, and outputs the corresponding signals to the controllers 3 and 6. The correction unit 18, for the purpose of preventing the flooding of the column and increasing its throughput, according to the signal from logic block 7, using information from pressure sensors 14 on the upper control one, reel and 1l of raw material consumption, generates an antifoaming agent flow value and through a matching unit 20 outputs a signal to the antifoam regulator 9 . If the rate of pressure increase on the control plate exceeds the allowable value

59731

Kr. CORRECT

the unit calculates the defoaming agent consumption by the formula

ihr-GM. (fPKT4- “P | CT-i..X (j,), 5

where (f kT1-G pressure change on the upper control plate for. time interval & t at 1st, (1-1) -th time instants; ®

RF, - raw material consumption in the f-th, (-1) -th time points.

If the rate of pressure decrease on the control plate exceeds ROnycKfPitTf .- fPitTiJneit rPuT, then the correction unit 5: unit 18 analyzes the change in raw material consumption from sensor 11. At F | .F

 otherwise, 2

calculation of the defoaming agent consumption value according to the formula (3).

Using this device allows you to increase the throughput capacity of the extractive distillation yolon by 2-3 and reduce the loss of products for the main components by 0.1-8.2%, which, with an installation capacity of 120 thousand tons of isoprene / year and isoprene cost of 530 rubles / ton gives an economic effect of approximately 90 thousand rubles. in year.

Claims (2)

1. USSR author's certificate f 565675, cl. B 01 D SL2, 1976. 2. USSR author's certificate tP, cl. B 01 D ЗД2, 05.26.77. Disti / 1tsa1