SU446820A1 - Method for automatic control of gas content in liquid and gaseous media - Google Patents

Description

The invention relates to methods for automatically controlling the content of gases B in liquid and gas environments and can be used in the chemical, petrochemical, coal and mining industries, as well as in other fields of science and production associated with the need to automatically control the gas regime of various mixtures of gases and liquids. .

A known method of automatically controlling the content of gases in liquid and gaseous media by passing the analyzed gas through a membrane of polymeric and other materials, dissolving it in the electrolyte of a potentiometric cell and measuring the pH of the electrolyte.

The disadvantages of the known method are the considerable duration of the establishment of an equilibrium between the analyzed medium and the electrolyte and the large delay in indications caused by the gradual

an increase in the concentration of the products of the reaction of the analyzed gas with an electrolyte, which is extremely slowly exchanging with the analyzed medium or not exchanging at all, as well as the absence of regeneration v. electrolyte and a constant decrease in measurement sensitivity. Due to this, the accuracy is reduced.

0 and the reliability of the control process.

in order to increase the accuracy and reliability of the control process in a potentiometric cell when measuring the pH of the electrolyte, it is also periodically regenerated by electrolysis of the regenerating solution.

1 shows a schematic diagram of an automatic control.

0 gas content in liquid and gaseous media; Fig. 2 shows graphs of the pH of an electrolyte of a potentiometric cell as a function of the content of the analysis of the Rushing Gas.

5 When the membrane I contacts the analyzed medium (solution or gas mixture) gas molecules (for example, COP) diffuse through the membrane into the interelectrode space filled with electrolyte 2, the pH value of the electrolyte is measured directly near the membrane using a glass electrode 3 - Comparison, with electrode 3 directly close to the membrane. Electrodes 5 and b of regeneration, separated by an ion exchange membrane 7 and immersed in a regenerating solution B, are placed behind electrodes 3 and (relative to the membrane) and, to avoid direct electrical contact with the latter, are separated from them by a perforated plate separator 9 of electrically insulating material. The potentiometric cell is located in the housing 10 of electrically insulating material. The diffused gas changes the pH of the electrolyte in the space between the electrodes 3 and 4, depending on the content of this gas. Further, the concentration of the reaction products of the analyzed gas with the electrolyte gradually increases so that the sensitivity of the potentiometric cell begins to fall. This moment includes regeneration electrodes 5 and 6, as a result of which the electrolytic decomposition of the regenerating

ipacTBOpa, diffusion of electrolysis products from the zone of electrode 5 through the separator 9 into the electrolyte and their interaction with the reaction products. As a result, the initial pH value of the electrolyte is restored. Further, the regeneration cycles are periodically repeated, in order to avoid mixing the electrolysis products formed on the electrodes 5 and 6, the latter are separated by ion exchange.

. membrane W. The change in pH of the electrolyte is recorded with a galvanometer.

Ii. The membrane I is permeable in practice. It is only for the analyzed gas, which provides selectivity

 measuring its content.

 INVENTIONS

A method of automatically controlling the content of gases in liquid and gas from foreign media by passing the analyzed gas through a membrane of polymeric and other materials, dissolving it in the electrolyte of a potentiometric cell and measuring the pH of the electrolyte so that In order to increase the accuracy and reliability of the control process, when measuring the pH of the electrolyte, it is simultaneously produced its periodic regeneration by electrolysis of the regenerating solution.

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WO9080

70 60

50 40

7.0 7.1 7.2 7.3 l 7.5 7.6 7.7 7.8 1.9 8.0 8.1

FIG. 2