SU959047A1 - Cellulose boiling control method - Google Patents

Description

The invention relates to pulp and paper production and can be used to control the pulping process.

There is a known method for controlling the pulping process by adjusting the average integral temperature, the duration of the impregnation stages of the chips with chemicals and the actual cooking 1.

The disadvantage of this method is that it does not provide the required quality pulp.

The aim of the invention is to ensure the required quality of JI-a. vines.

This goal is achieved by the fact that according to the method of controlling the pulping process by means of regul. the average integral temperature, the duration of the stages of impregnation of chips with chemicals and the cooking itself, determine the value of the depth of impregnation of chips with chemicals according to the current average integral temperature, the concentration of active reagent in the cooking pacTBOpje, the quality of the wood chips and the amount of mismatch of the result of the found and found, and found the results of the found patterns of the found and found and found the result of the distressed patterns. regulate the average integral temperature of the impregnation stage, and the duration of the impregnation stage of the chips is controlled by the actual value NIJ index impregnation depth defined by the formula

l y-

-3163.1 ,,. G1 ,.

CIt; dt,

T (t)

ten

where X is the impregnation depth indicator

chemical chips; A - adjustable coefficient; ) is the average integral process temperature;

15

С (t) is the concentration value of the active reagent in the m. Moment of time t; n - coefficient of sensitivity

the impregnation process to change20. No concentration of active

reagent ,,

Moreover, the final average integral temperature of the impregnation and cooking stage is adjusted depending on the concentration of the active reagent at the time the impregnation depth reaches the specified value and the duration of the cooking stage, determined by the technological regulation of the cooking department and the required quality indicators for the pulp.

The drawing shows a diagram of the device that implements the proposed method. .

The circuit contains a sensor 1 liquid temperature, a digester 2, a sensor 3 liquid temperature, a heater, a calculation unit 5, a control unit b, a concentration sensor 7, a comparison unit 8, a setting unit 9, a calculator: a unit 10, a relay unit 11, a comparison unit 12, a setting device 13, a steam flow controller 14, a valve 15, setting devices 16 and 17, a ratio block 18, a computing unit 19. ....

The device is operated as follows.

According to the temperature measurement data, at least at two points of the apparatus, for example, the temperature sensor 1 of the liquid at the outlet of the digester 2 and the temperature sensor 3 of the liquid at the furnace of the preheater 4 and in the calculation block 5, determine the average integral temperature of the digester at a given time . The value of the average integral temperature from block 5 is fed to the block with the actual value of the depth of wood chips impregnation with chemicals, which is determined taking into account the measured concentration of the active agent with sensor 7 by the formula

T

.j.

e C (. valid

the value of the impregnation depth indicator comes from block 6 to the comparison block 8 with the specified value received from block 9.

According to the sensor 7. The concentration of the active reagent in the cooking solution and the specified value of the impregnation depth indicator from the sampler 9 in the computing unit 10 determine the required value of the average integral temperature of the impregnation stage, which through the relay unit 11 enters the comparison unit 12 of the specified and actual average integral temperatures. The mismatch from block 12 enters the setting device 13 of the controller 14 of the steam consumption for heating; From the output of the regulator 14, a control is applied to the valve 15 of the steam flow rate. . . ::,: ..

Upon reaching a predetermined value by the impregnation depth indicator, the comparator unit 8 issues a signal to the relay unit 11 to turn on the operations of controlling the cooking stage.

On the instructions of the knob 16 productivity of the cooking department and

The task of the generator 17 indicators of the quality of the obtained cellulose, block. The ratio of 18 mouths gives the required duration of cooking. Based on the calculated cooking time from unit 18 and data on the concentration of the active reagent sensor 7 at the time of the operation of the relay unit 11, the computing unit 19 determines the required final integral temperature of the pulping stage and transmits the cooking processes through the blocks 11-14 to valve 15.

When the required duration of the cooking stage is reached, the process ends.

Thus, the proposed process control method allows the required amount of pulp to be provided.

Claims (1)

1. USSR author's certificate 666524, cl. D 21 3/00, 1979. L