SU1370534A2 - Device for conductometric tolerance check of liquid composition - Google Patents

Abstract

) The invention relates to devices for automatically determining the concentration of substances dissolved in a liquid by electrical conductivity and can be used for conductometric tolerance control of the salt content in the output condensate of a group of low-pressure preheaters, control of acidity of wastewater of a sulphate acid coolers during the circulation cycle of water supply and other technological processes . The aim of the invention is to increase the reliability and reliability of the control - is achieved by isolating the tolerance signal of conductometric sensors that do not have contact with the controlled fluid, while maintaining conductometric control of the minimum electrical conductivity of the liquid. The device contains conductometric sensors 1-5 (their number is chosen equal to the number of liquid streams), signal switching unit 6, unit 7 for measuring the conductivity of the liquid, the correction unit 8, comparators 9-13, units 14 and 21 of the comparison, blocks 15 and 22 indications, comparators 16-20. 1 il. (L

Description

with

 L

with

four

14)

The invention relates to devices for the automatic determination of the concentration of substances dissolved in a liquid by electrical conductivity and can be used for the conductometric control of the salt content in the output condensate of a group of low pressure preheaters having a common heat supply source, in the form of steam from a thermal and atomic turbine unit. power plants to control the acidity of wastewater sulfuric acid refrigerators during the cycle of water supply and other technological processes s.

The purpose of the invention is to increase the reliability and reliability of monitoring by the puds of the comparison blocks 14 and 21, the latter being equipped with indicator blocks combined into blocks 15 and 22, respectively. In addition, the outputs of the comparators 16-20 are connected to the corresponding control inputs of the switching unit 6.

The device works as follows.

From conductometric sensors 1-5 installed at the sampling sites for liquids, the signals arrive through the open inputs of the switching unit 6 to the input of the unit 7, which performs the function of extracting the extremum of the minimum signal min and feeding it to the input of the correction unit 8, in which

the selection of the signal of the conductor tolerance is 20 summation of the minimum signal

tomometric sensors that do not have contact with the controlled fluid, while maintaining conductometric tolerance control on the signal of the minimum electrical conductivity of the liquid. I

The drawing shows a block diagram

devices for conductometric tolerance control of the composition of liquids (in this case, condensate of low-pressure heaters).

The device contains conductometric sensors 1-5 in an amount equal to the number of fluid flows (a case is depicted when the number of flows is equal to five); the outputs of the conductometric sensors are connected to the information inputs of the switching unit 6, the outputs of which are connected to the inputs of the unit 7 for selecting the reference value of the conductivity of the liquid, made in the form of a minimum value extremum separator; the output of block 7 is connected to the input of block 8 for correcting the magnitude of the electrical conductivity deviation, the first

the output of which (Xc X,

+ $ -} is connected to the combined second inputs of the comparators 9-13 of the comparison block 14; display unit 15; The second output of block 8 (XD t} is connected to the combined second inputs of the comparators 16-20 of the second comparison unit 21. The connection nodes of the inputs of the comparators are structurally the inputs of the reference voltage of the first 14 and second 21 comparison blocks. 16-20 are combined in pairs (9 s 16; 10 s 17; ... 13 s 20) and are signal inputs of the tolerance signal cG. The control signal X "received at the first output of the correction block 8 goes to the combined second inputs of the comparators 9- 13 block 14 comparison, from the second output of block 8 correction and the tolerance signal X d is fed to the combined second inputs of the comparators 16-20 of block 21 as compared to

0 neither. At the first inputs of comparators

9-13 and 16-20, signals are provided from the respective, outputs of the conductometric sensors 1-5. In case of exceeding any controlled signal (from conductometric sensors

0

five

0 5

1-5) of the control signal X, the corresponding comparator (comparators 9-13) triggers, including the output signaling device of the display unit 15.

When the contact with the controlled medium is lost by any of the conductometric sensors, the signal from the corresponding sensor decreases to a value less than the tolerance signal Xj сГ, the corresponding comparator (controllers 16-20) is triggered and disconnects this signal from the conductometric sensor from the extremum selector minimum value unit 7 using block 6 switching signals. In addition, the output device for signaling the malfunction of the additional display unit 22 is turned on.

Claims (1)

Invention Formula Device conductometric tolerance control of the composition of the liquid31370534 Stey on auth. No. 1182366, about tl and -sharing the minimum value is electrically so that, with the purpose of conduction through the fail-over unit and reliability of signals, the inputs of the control signal board, the comparators are connected to it and the corresponding outputs are connected comparison, made of thermal sensors, other inputs in the form of a set of comparators, the number of co-comparators is connected with the additional ones equal to the number controlled by the liquid output of the correction unit, the inputs bones, an additional block of indie (a- Q additional block of the indication of sociation, and the conductometry outputs are connected with the corresponding outputs These sensors are connected to the unit of the second comparator unit.