RU2739458C1 - Catalytic filter - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to purification of air from organic impurities by oxidation thereof in the presence of a catalyst. Cleaned air can be further used as gas carrier for gas chromatography. Catalytic filter comprises a thermistor arranged on a nichrome wire cartridge with a deposited catalyst layer enclosed in a tubular furnace of stainless steel. Tubular furnace chamber makes volume of 3 millilitres, and its operating temperature is 240–250 °C.

EFFECT: technical result is reduction of resource and power costs during cleaning process, due to reduction of dimensions of catalytic filter device for air purification from volatile organic compounds.

1 cl, 1 dwg

Description

The invention relates to air purification from organic impurities by oxidation in the presence of a catalyst. The purified air can then be used as a carrier gas for gas chromatography.

There is a known method of air purification from organic impurities, in which air with impurities of organic substances, such as butanol, is passed through the zone of a pulsed gas discharge, then the gas to be purified is passed through a photocatalyst unit. The latter may contain tubular glass elements on which a TiO ₂ layer is applied. The photocatalyst is illuminated with a light source in the visible or ultraviolet range. At the stage of photocatalysis, complete gas purification from organic matter impurities is achieved (see: A.A. Vargauzin, G.N. Kuzmin, S.V. Kurganov, G.L. Spichkin, E.K. Chistov, a method for air purification from organic impurities, RU 2071816 C1, 1997).

Known adsorption-photocatalytic device for air purification from volatile pollutants, capable of effectively destroying periodic emissions of volatile pollutants in one pass, without the formation of intermediate compounds at the outlet, consisting of a housing, a cylindrical photocatalytic unit with a UV lamp, a fan, a dust filter with an applied adsorbent located around the photocatalytic unit (see: A.A. Pershin, M.V. Starkov, adsorption-photocatalytic device for air purification from volatile pollutants, RU 33035 U1, 2003).

A device for combined air purification is known, consisting of sections of electrostatic filtration, photocatalytic oxidation and adsorption purification, the precipitation part of the electrostatic filter is shortened, the carriers of the photocatalyst are made of a conductive material with a resistance of less than 1 MΩ and are grounded, and an ozonation unit is located in front of the photocatalytic section, contributing to the regeneration of the photocatalyst when working in a highly polluted atmosphere (see: Kozlov D.V., Vorontsov A.V., Mukhin V.F., device for combined air purification, RU 99348 U1, 2010).

The disadvantage of the known devices is the sufficient complexity and bulkiness of the structures due to the multistage cleaning system. In addition, the known devices are characterized by high power consumption and high reactor temperatures, which do not imply their use in the field.

Known device for catalytic oxidation of gaseous compounds, which consists of a housing with inlet and outlet pipes, inside which is placed a block carrier made of open-cell metal foam, covered with layers of secondary carrier and catalytically active substance. When the block carrier reaches a stationary operating temperature, the reaction of catalytic oxidation of gaseous compounds occurs in the device, (see: Danchenko Yu.V., Dorogokupets G.L., Ivanov O.E., Kulakov S.V., Kuprin P.B., Melnikov M.Yu., Perelman O.M., Rabinovich A.I., device for catalytic oxidation of gaseous compounds, RU 2305585 C2, 2005).

Known filter for catalytic cleaning of carrier gas (nitrogen, and simultaneous purification of nitrogen and air), produced by META-CHROM (Yoshkar-Ola), containing a heater placed in a rectangular metal case. The reactor of this filter is made in the form of a stainless steel tube with fittings (passport MET2. 508.005PS.2001).

The closest to the invention in terms of a combination of essential features is a catalytic filter developed at ZAO SKB Khromatek (Yoshkar-Ola) for purifying gases from impurities by heating them to a temperature of 500-600 ° C in the presence of a catalyst. The known filter contains a casing inside which a reactor is installed. The reactor vessel is made in the form of a sealed cylinder with inlet and outlet gas pipelines connected to it. At the ends of these pipelines, an inlet connection, an outlet connection and a plug connection are located. Thermal insulating material is placed between the reactor with the heater and the filter casing. There is no thermal insulation in the lower part of the filter, therefore, a part of the inlet pipeline and the outlet pipeline provide thermal decoupling between the heated reactor and the fittings. A ventilation channel is formed by a side wall of the casing and a heat-insulating material, and ventilation holes are made in the lower and upper parts of the casing. As a result of thermal decoupling, the temperature at the bottom of the filter is close to the ambient temperature. This ensures a long service life of the nozzle seals, (see: Ivanov PB, Starikov AI ZAO Scientific Center Chromatek. Catalytic filter. RU 2205060 C1).

The disadvantages of the known devices can also be attributed to the large dimensions of the devices and the need to create a high temperature in the reactor for the catalytic oxidation of organic compounds contained in the air.

The objective of the invention is to reduce the size, power consumption and reduce the operating temperature of the reactor of the catalytic filter device for air purification from volatile organic compounds, which reduces resource and energy costs during the purification process.

This problem is solved due to the fact that a catalytic filter containing a thermistor located on a cartridge made of nichrome wire with a catalyst layer applied, enclosed in a stainless steel tubular furnace, while a platinum catalyst is applied to the nichrome wire, the tube furnace chamber has a volume of 3 milliliters , and its operating temperature is 240-250 ° C.

When solving this problem, a technical result is created, which consists in reducing resource and energy costs during the cleaning process, by reducing the size of the catalytic filter device for cleaning air from volatile organic compounds.

The invention is illustrated by a drawing, which shows a diagram of a catalytic filter. The catalytic filter contains a thermistor 1 located on a cartridge made of nichrome wire with an applied catalyst layer 2, enclosed in a stainless steel tube furnace 3.

The catalytic filter works as follows: air enters through a capillary into the filter working chamber, which includes a thermistor 1 located on a nichrome wire cartridge with a catalyst layer applied 2, enclosed in a stainless steel tube furnace 3. When the filter chamber is filled with purified air, it is heated to temperatures 240-250 ° C in the presence of a catalyst. As a result, volatile organic compounds in the air are oxidized to carbon dioxide.

The use of the proposed catalytic filter can significantly reduce energy consumption for the air purification procedure, while the device allows complete oxidation of volatile organic compounds in the purified air.

Claims (1)

A catalytic filter containing a thermistor located on a cartridge made of nichrome wire with a catalyst layer applied, enclosed in a stainless steel tubular furnace, characterized in that a platinum catalyst is applied to the nichrome wire, the tube furnace chamber has a volume of 3 milliliters, while its operating temperature is 240-250 ° C.

Images