RU61427U1 - SENSOR OF REACTIVITY OF GAS AND CONDENSED PRODUCTS - Google Patents

Abstract

The utility model relates to measuring and controlling the chemical activity of gaseous and condensed products, as well as their mixtures and registration of chemically active components of gas mixtures. The principle of operation is based on the Seebeck thermoelectric effect, two platinum rhodiums are used for its implementation - platinum thermocouples 1 and 2 connected to a bridge electric circuit. The bridge is used to compare signals from a thermocouple 2 with an isolated junction and thermocouple 1 with an uninsulated junction, converting chemical activity into an electrical signal, which is measured by a thermo-emf measuring device. 10. The positive effect is achieved through the use of two effects simultaneously in the joint work — the catalytic effect of the materials of the working junction of thermocouple 1 for detecting chemically active components, as well as the thermoelectric effects of two thermocouples 1 and 2 (with and without coating) for measuring the relative value of chemical activity , since thermocouple 2 acts as a comparative element.

Description

The utility model relates to measuring and controlling the chemical activity of gaseous and condensed products, as well as their mixtures and registration of chemically active components of gas mixtures. It can be used for gas analysis in the petrochemical industry in control systems for the synthesis or decomposition of gaseous substances, as well as a detector of chemically active components of gas mixtures for their registration or control in chemical chemistry of fuel, plasma chemistry, exhaust or flue gas exhaust systems, and in scientific research.

The closest technical device to the proposed utility model is a thermoelectric pyrometer, which is a series connection of a thermoelectric transducer, which is a thermocouple made in the form of two conductors of dissimilar materials fastened together by two ends to a working junction, and a device for measuring thermoelectric power .s. (see Electrical measuring instruments and measurements: V.O. Arutyunov. - M.: State Energy Publishing House, 1958. - 631 s, EE-5-2; p. 566).

The disadvantages are: a narrow range of measured parameters.

The purpose of the utility model is to increase the versatility of the device.

The goal is to measure the reactivity of gaseous and condensed products, which is a series connection of a thermoelectric converter, which is a thermocouple made in the form of two conductors of dissimilar materials, fastened together by two ends to a working junction, and a device for measuring thermoelectric power. C., achieved by the fact that the device introduced a second thermocouple, the working junction of which is covered with a thin layer of heat-resistant passivating composition, the free ends of the thermocouples with are interconnected with the thermo-emf measuring device according to the principle of electric bridge connection, the shoulders of which are working junctions of thermocouples, the materials for the conductors of each thermocouple are platinum rhodium and platinum, the thermocouples are placed in a sealed case and filled with a heat-resistant compound, working junctions brought out of the body.

The essence of the utility model is illustrated by the diagram in figure 1, where 1 is platinum rhodium is platinum thermocouple No. 1, and 9 is a positive electrode of thermocouple No. 1; 2 - platinum rhodium - platinum thermocouple No. 2 with a heat-resistant insulating coating - 4, and 8 - a positive electrode of thermocouple No. 2; thermocouples are interconnected and with a device for measuring thermo-emf-10 in a bridge electrical circuit; thermocouples are filled with a compound - 7, placed in a housing - 5, made for example of steel

which are insulated with an insulator - 3, and in the upper part - with a sealant - 6; working junctions of thermocouples 1 and 2 are led out of the housing 5. For durable, reliable operation, thermocouples are filled with a heat-resistant compound, for example, K-30 hot-cure polyurethane. For heat-resistant insulation coating 4 thermocouples 2 use a heat-resistant passivating composition, such as Teflon, glass.

The device operates as follows. Housing 5 by working junctions of thermocouples 1 and 2 is placed in the test gas mixture, for example, in the products of plasma-chemical conversion of hydrocarbons. As a comparative element, a thermocouple 2 is used, isolated from the chemical environment. Since the temperature of the medium near the junctions of thermocouples 1 and 2 is the same, the same thermo-emf value is generated in thermocouples, depending on the temperature of the working junction. At the shoulders of the bridge are the same thermo-emf. mutually cancels each other - the arrow of the device for measuring thermo-emf. 10 does not deviate. If the composition of the gas mixture or condensed products contains chemically active components, then by reacting (an accelerated chemical reaction due to the catalytic effect of platinum) on the surface of the working junction of thermocouple 1 with the release or absorption of heat, they contribute to a change in temperature of the junction of thermocouple 1, therefore the thermo- emf from this thermocouple (Seebeck effect). The voltage at the terminals of thermocouples 1 and 2 becomes different and the arrow of the device for measuring thermo-emf. 10 will deviate in one direction or another, depending on whether chemical reactions took place with the absorption or release of heat.

The positive effect of the device is to provide the ability to signal the presence of chemically active components in the mixture of gaseous and (or) condensed products of interest and measure the level of reactivity of the mixture by using a combination of two effects at the same time - the catalytic effect of platinum and the Seebeck thermoelectric effect, which improves performance , expand the scope of the device, provide a wide range of operating conditions.

Claims (1)

The reactivity sensor of gaseous and condensed products, which is a series connection of a thermoelectric converter, which is a thermocouple made in the form of two conductors of dissimilar materials, fastened together by two ends to a working junction, and a device for measuring thermo-EMF, characterized in that he introduced a second thermocouple, the working junction of which is covered with a thin layer of heat-resistant passivating composition, the free ends of the thermocouples are connected to each other and to the device for measuring the thermo-electromotive force by means of electric bridge connection, which shoulders - working thermocouple junctions, material for conductors of each thermocouple is Platinum and platinum thermocouple placed in a sealed enclosure filled and heat-resistant compound, workers junctions withdrawn beyond the housing.