SU800857A1 - Electrochemical concentration meter sensor - Google Patents

Description

one

This invention relates to α-instruments for measuring the concentration of liquid media by an electrochemical method and. It can be used in the chemical food and other industrial fields, especially for measuring the concentrations of ions in electrolyte solutions containing sediment-forming

substances.

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A known sensor of an electrochemical concentrator, containing an indicator electrode and a remote reference electrode, is fixed in a housing made in the form of a flange, in which is placed a device for cleaning the contacting part of the indicator electrode, which includes a rubber membrane. The sensor allows pH measurements in films and sediments of industrial solutions pj.

A disadvantage of the known device is the low reliability of the mechanical cleaning unit of the indicator electrode, as when sinking on the rubber membrane the quality of cleaning the indicator electrode deteriorates dramatically. As a result, the measurement reliability decreases. whole

The most technical solution to the proposed is an electrochemical concentrator sensor,

containing renewable indicator and nonpolarizable electrodes fixed in the device for their translational movement in the course of measurement in order to renew the surface "in contact with the measured medium. The electrodes are placed through bushings with seals in a flow housing made of electrically insulating material. Housing along with outside device

5 for updating the contacting part of the electrodes is placed on the board of electrically insulating material. Analyzed medium, pre-cleaned from mechanical suspensions,

0 comes from the industrial apparatus into a flow housing with electrodes for measuring the concentration of ions 2.

The disadvantages of this sensor are to reduce the reliability of measurements in

5 environments intensively precipitating precipitates on the elements of the sensors, including the internal walls of the flow-through loop-shaped body. In addition, the need for pre-cleaning

0 The analyzed liquid from mechanical suspensions, for example, fibrous materials, in special filters, hydraulic cyclones or settling tanks, on the surface of which the precipitates are also precipitated, causing the measurement to be delayed.

The purpose of the invention is to increase the reliability of the sensor by preventing the deposition of precipitates on the inner walls of the housing and supply lines, improving the measurement accuracy and expanding the functionality of the application.

This goal is achieved in that an additional auxiliary electrode is inserted into a sensor containing a renewable indicator electrode, placed in an electrical insulating material, an auxiliary electrode and a device for fixing and moving an indicator electrode, and the body is made in two stagnant sealed glasses, installed coaxially with the indicator electrode at a distance from one another and connected by a zipper through the tube. renewable indicator electrode; in this case, a device for fixing and moving the renewable indicator electrode is placed in one glass, and in another - a device for breaking off the waste part, and an electrically conductive surface of the process apparatus is used as an additional auxiliary electrode, and a device for removing waste part of the renewable electrode is made in the form of a beveled protrusion on the inner surface of the glass.

In the drawing a schematic representation of the proposed sensor electrochemical concentrator.

The sensor includes a housing made in the form of two non-flowing sealed glasses 1 and 2 installed coaxially and connected by a stitch 3, an updated indicator electrode 4 located along the axis of the glasses, and an electrode 5 with an electrolytic key B. filled with KCE solution. Electrodes 4 and 5 are connected to potentiometer 7. Both cups are made of electrically insulating material and sealed with sleeves 8 with seals 9 through which the updated indicator electrode 4 is passed. In device 1, a device 10 is placed to fix and move the updated indicator electrode driven by a synchronous motor 11. In the cup 2 on the inner surface there is a beveled protrusion 12 for breaking off the waste part of the renewable indicator electrode. Both parts of the housing are ksirovany Art zhkoy 3 spaced from each other defining a length emom active portion contacting with a solution of the indicator electrode, rasprlozhennoy seals between faces 9, dependent upon the specific conditions of physico-chemical measurements.

The sensor is installed directly in the process apparatus 13, immersing the housing in the investigated electrolyte solution. As an additional auxiliary electrode, an electrically conducting surface of the apparatus is used, one of the elements of which is connected to the source 14 of a stabilized voltage, and the indicator electrode 4 is connected to the Kotopoi via a capacitor 15.

Measurements with a sensor are performed as follows.

The sensor is immersed in the electrolyte solution located in the process apparatus 13 to such a depth that, with all changes in the electrolyte level in the apparatus, the electrode 4 is immersed in the electrolyte. Next, a synchronous motor 11 is switched on, with which the indicator electrode 4 is set in motion, and a stabilized voltage source 14. After the electrode 4 advances no less than 1/2 the length of the gate between the ends of the seals 9, the readings of the concentrator are measured. using potentiometer 7.

After 5-10 days after the electrode is completely consumed, the sensor is removed from the technological apparatus, the device 10 is installed to move the electrode to its initial position, and the cup 2 is released. from debris electrode, insert a new electrode, screw the beaker 2 and immerse the sensor in the electrolyte for subsequent measurements.

Making the body in two parts in the form of staggered sealed glasses, through which the renewable electrode coaxially passes through, allows its contact with the test electrolyte solution only in the area that is working at a given time. At the same time, the electrolyte under study is located outside both parts of the housing in the free volume of the apparatus where it, unlike the flow-type sensor, is not susceptible to clogging with mechanical impurities, thereby increasing the reliability of the sensor.

. Cleaning the sensor from precipitated precipitates is facilitated) - since it is necessary to clean the outer surfaces, which is especially important in the presence of precipitates that are difficult to dissolve even with special reagents (for example, CeESO gypsum). This eliminates pre-cleaning devices, which helps reduce measurement lag.

Claims (3)

Claim 1. The electrochemical sensor con- _I .tsentratomera comprising an indicator electrode x0, placed in a housing of electrically insulating material, an auxiliary electrode and a device for fixing and moving the indicator electrode to update its contact portion, characterized in that, in order to increase reliability by prevent precipitation on the inner walls of the housing and improve the accuracy of 20 measurements, it contains an additional auxiliary electrode, and the housing is made in the form of two non-flow sealing bathtubs installed -> coaxially with the indicator electrode 25 'and an indicator electrode is passed through both glasses, with a device for fixing and moving the indicator electrode along the axis of the glasses and a device for removing its spent part in another. 2. The sensor according to claim 1 ,. It is due to the fact that the electrically conductive surface of the technological apparatus is used as an additional Auxiliary electrode. 3. The sensor according to π.1, characterized in that the adjustment for removing the spent part of the indicator electrode is made in the form of a chamfered protrusion on the inner surface of the glass.