SU1535909A1 - Method of controlling the process of continuous digestion of sulfate pulp - Google Patents

Abstract

The invention relates to pulp and paper production and can be used to automatically control the process of continuous sulphate pulping. The purpose of the invention is to reduce the stiffness fluctuations of the pulp produced. To do this, in the liquor flow control system in the Kamyur type two-chamber cooking vessel, which includes controlling the flow rate of liquor to be withdrawn by the liquid level in the boiler, the temperature of the liquor to be withdrawn is also measured and the flow of the washing liquor to the boiler is controlled depending on the mismatch of the measured values and the set temperature of the selected liquor. The position of the lower boundary of the cooking zone is controlled not by the consumption of heating steam, which heats the cooking liquor circulating in a closed circuit, but by the flow of cold wash liquor fed to the lower part of the boiler. 2 Il.

Description

one

(21) 8100/23-П

(22) 12.22.87

(6) 01/15/90. Bol N1 2

(71) Astrakhan special design and technology bureau with pilot production

(72) V.S.Belov and V, A „Druzhinin (53) 676.о :. (088.8)

(56) USSR Copyright Certificate No. 926131, cl. P 21 S 7/12, 1075. Mate; piles 12-1

S - C I SIST WITH WE

p.116-125.

Tzlancepa I.L., Filipenko S.M. Management of liquor flows and the level of liquid in the boiler of the cooking plant with a portable intermediate track. Sat scientific papers VNIB Agtsmatizatsii and mechanization of production processes in the pulp and paper industry, Leningrad 986. (} THE METHOD IS MANAGED ;, THE HEfiPFPhiShQii PROCESS AND SULPHATE CELLULOSE (57 The invention relates to cellulose 37, Stoke.,

concise pulp and paper industry

Sobolev O.F

paper production and can) be used to automatically control the continuous process of sulfate pulp. The purpose of the invention is to reduce the stiffness fluctuations of the pulp produced. To do this, in the liquor flow control system in the Kamyur-type two-chamber cooking boiler, which includes controlling the flow rate of the liquor to be extracted, the liquid level F is additionally measured, the liquor withdrawn and the flow of the washing liquor to the boiler is controlled depending on the error measured and set temperature of the selected liquor. The position of the lower boundary of the cooking zone is controlled not by the consumption of heating steam, which heats the cooking liquor circulating in a closed circuit, but by the flow rate of the cold wash liquor supplied to the bottom of the coagle. 2 Il.

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 Genia is a pulp and paper industry and can be used to automatically control the process of continuous cooking from pulp.

The aim of the field is to reduce the fluctuations of u fCTKc Ti of the caseable pulp by staiE, - the position of the lower boundary of the cell line.

Cha FIG. 1 nptqc scheme of the device, peaping method of controlling the process of continuous cooking of sulfate, fatah pulp; Fig. 2 is a diagram of temperature distribution with a deviation of the lower boundary of the cooking zone.

The device contains a digester 1 with screens 2 liquor extraction, a sensor 3 levels of liquor in the boiler, a valve for regulating the flow of the liquor to be withdrawn, a valve 5 for regulating the flow of the washing liquor, a sensor 6 for the temperature of the liquor to be withdrawn, a regulator

7 flow rate of the washing liquor, collector 8 of supplying the washing liquid to the boiler, regulator of the 9th level of the liquor in the boiler.

For the Kamur apparatus, the temperature distribution (T) over the height of the boiler is related to the spatial coordinate Y by the ratio

T Y / V,

where V is the speed of movement of the mixture of chips-lye in the boiler.

The cooking zone is the cross section of the boiler, limited by Y Y coordinates (and in a two-chamber digester, a Y point can be taken as a point corresponding to the HQ liquor level in the boiler) and Y is the coordinate of the delignification reaction end point, where the temperature of the reacting chip mixture The alkali drops to 1.5-150 ° C due to the cooling of this mixture with a stream of washing liquor to the boiler. This point is the lower boundary of the cooking zone.

It is known that the value of the H-factor can be calculated by the following dependence

v -jMnxiv)

H

k-e-dCY / V)

X, / V

where P is the reaction rate constant of the drlinikifik di di wood; T (Y / V) - temperature distribution

the height of the boiler; V - speed of movement of the mixture

chips-lye in the boiler; k - exp / 1 "3,2 /; Y, and Y4 - the position of the coordinates, limiting the cooking zone. Since the position of Y influences the value of the H-factor, and the magnitude of the latter is in a linear relationship with the rigidity of the pulp, it becomes obvious that the position of the lower boundary (Ya) of the pulping zone is stabilized.

The method is implemented as follows.

In steady state, the hot liquor from the cooking zone enters the extraction zone, where it is mixed with the cold washing liquor. The temperature of the selected liquor T0, 150 ° C corresponds to the setpoint T0 - setting the controller 7, at which the nominal flow rate Qn of the washing liquor is maintained.

An increase in the flow of hot liquor from the cooking zone due to uncontrolled disturbances (change in the moisture of the chips, change in the consumption of heating steam supplied to the boiler, etc.) will shift the boundaries of the zone in which the hot and cold liquors are mixed and the temperature changes accordingly. ) from the extracted liquor. In this case, the regulator 7 will issue a control action to the valve 5, which changes the flow rate of the washing liquor, which in turn returns the extraction zone to the previous limits.

An increase in the level of liquor in the boiler due to an increase in the consumption of the washing liquid is stabilized by the regulator 9.

Adjusting the lower boundary of the cooking zone with the flow rate of the washing liquor according to the temperature of the liquor to be extracted, together with the circuit for stabilizing the level of liquor in the boiler, will reduce the fluctuations in the hardness of the pulp produced.

Claims (1)

Invention Formula The method of controlling the process of continuous sulphate pulping, which includes controlling the consumption of liquor in the extraction zone for the liquid level in the boiler, characterized in that, in order to reduce the stiffness fluctuations of the produced pulp by stabilizing the lower boundary of the cooking zone, the flow of leaching liquor is proportionally controlled the magnitude of the mismatch between the measured and set temperatures of the liquor selected. Boundary of the barque zone Liquor Flow Up Boiler Industrial slurry Uch J and / Level of chips 6 ko / ple f--, Of - Stream liquor To bottom byduVka 1