SU697152A1 - Method of automatic control of suspension - Google Patents

Description

The invention relates to methods for automatically controlling the process of filtering suspensions and may find application in the chemical, electrochemical, hydrometallurgical and other industries.

A known method of automatically controlling the filtration process by measuring the ratio: the rotation speed of the vacuum filter — the thickness of the precipitate and its adjustment depending on the quality of the solid product; the obtained figure is entered into the regulator acting on the lower vacuum 1.

The closest is the method of automatically controlling the process of filtering the suspension by bringing the filter to regeneration by the pressure drop across the filter and the flow rate of the filtered suspension 2.

The disadvantage of these methods is that they do not provide the sensitivity and reliability of controlling the process of filtering the suspension when the pH of the filter medium fluctuates over a wide range, which take place in industrial conditions.

In this case, the dissolution of the solid phase and the contamination of the resulting filtrate, which is fed to the final product, is observed with soluble impurities.

The aim of the invention is to increase the sensitivity and reliability of control of the filtering process. This goal is achieved by the fact that the filter output for regeneration is additionally taking into account changes in the pH of the filtered suspension.

The drawing shows a schematic diagram of the implementation of the proposed method of automatic control of the filtering process.

The liquid to be purified, for example, the pH of medium 12, enters through the inlet pipeline 1 and passes through filter 2.

The filtrate through line 3 is diverted to the redistribution to obtain the finished product from it.

During the filtration process, the pH of the filtered fluid is measured by a flow sensor 4 mounted on the inlet pipe.

If the pH of the suspension to be filtered becomes less than 12 (for example, when filtering magnesium hydroxide to PUR S, 0), a precipitate dissolves on the filter element, resulting in an abrupt decrease in the pressure differential across the filter,

In this case, the signal from the flow sensor 4 is fed to a high impedance converter 5, the output of which is, and, a, em to the secondary device 6, where it is converted into a signal proportional to the abrupt reduction in pressure drop across the filter at a certain pH. Using differential pressure gauge 7, the differential pressure across the filter is measured.

The output signals from the differential pressure gauge 7 and the secondary device b are fed to the device 8.

In case of exit; : ,,:: differential meter 7 also abruptly (} sconce: ;;; 0 / change PPG, device 8 will give a signal to the automatic fn, about 2 from the technological scheme for recH shrapia.

The use of this method will improve the quality of life. and reliability of quality control filtering compared with the known methods, and improve the quality of the finished product.

Claims (2)

Invention Formula The method of automatic control of the filtering process of suspensions by bringing the filtrate to regeneration but the pressure drop across the filter, characterized in that, in order to increase the sensitivity and reliability of the control of the filtering process, the filter output to regeneration is carried out fully pH of the filtered suspension. Sources of information that are given: c () attention during examination. USSR author's certificate JMo 341504, M., cl. On 01 D 37/04, 1970. 2. USSR author's certificate No. 437517, M .., cl. On 01 D 37/04, 1972 (prototype). ...-. i t: i