SU447467A1 - Method for automatic adjustment of the work of the grinder - Google Patents

Description

one

This invention relates to the automatic regulation of wood pulp production in the pulp and paper industry.

There is a method for automatically controlling the operation of grinders, based on measuring the signal from the performance of the grinder. In this method, the performance of the grinder and the power consumed by the grinder stone drive motor are measured, the specific energy consumption per tonne of air-dry fiber is calculated, compared to a predetermined value, and the balance feed motor is controlled at a constant value. However, this method does not control the material and heat balances of the grinder. This, in turn, does not provide for the regulation of the temperature of the finisher and the concentration of wood pulp in the softener bath with a sufficient degree of accuracy (the latter is especially important for dipping the stone into the bath).

The purpose of the invention is to regulate the material and heat balances of the pulper.

This is achieved by additionally measuring a signal proportional to the flow rate of circulating water, calculating the ratio of the signal of the output of the grinder to the signal2

proportional to the flow of circulating water, and use this ratio to regulate the flow of circulating water.

The drawing shows a schematic block diagram of an automatic control system intended for the implementation of the proposed method. .

The consumption of wood pulp in the chute after the bath of the grinder is measured by a hydrodynamic flume meter 1 of the flow rate, and the flow of circulating water supplied to it for all the pullers of the cooler is measured by an induction flow meter 2.

The signals from the outputs of the flowmeters are converted by transducers 3 and 4 into unified pneumatic signals. In block 5 of the simplest algebraic operations, the difference of signals is calculated proportional to the consumption of absolutely dry fiber, i.e.

the performance of the grinder. After amplification in multiplication unit 6, a signal proportional to the performance of the fertilizer is fed to a regulating unit of ratio 7 with a remote setting of the ratio value and a secondary pneumatic recorder with a control station 8. A signal proportional to the flow rate of circulating water supplied to

drops of the grinder.

Changes in the flow of circulating water mainly occur at the expense of the flow that flows directly to the bursts of the fertilizer stone, since the flow of circulating water supplied to the third drop to dilute the mass in the groove is almost constant.

The pneumatic signal from the output of the regulating unit of ratio 7 is fed to the power amplifier 9 and further to the regulating valve 10 with a pneumatic diaphragm actuator, which controls the flow of circulating water directly to the drift stone jumpers.

Adjustable value of the ratio between the performance of the absolute dry fiber fiber and the flow of recycled water directly to the showers

stone grinder, determined experimentally when setting up the automatic control system on the grinder.

Subject invention

A method for automatically adjusting the operation of the ribber, consisting in measuring the signal according to the performance of the ribber

characterized in that, in order to ensure the regulation of the material and thermal balance of the fibber, the signal proportional to the flow of circulating water is additionally measured, the ratio of the signal is calculated

the performance of the grinder to the signal proportional to the flow of circulating water, and use this ratio to regulate the flow of circulating water.