Gases

As fuel- use natural gases the fuels and obtained artificially in the form of basic (generator G.) or side-line (coke, domain and other G.) production. Osn users natural g. in ferrous metallurgy - domain and Martin production. With the use natural g. it is produced yearly by ok. 60% of cement, 60% of glass, SV. 60% of keramzit, SV. 60% of ceramics. The transfer of the glass furnaces into natural g. considerably improves the technical-economic indices of the production of glass. In the fuel balance Masha- constructs, industry in the portion combustible g. it is ok. 40%. Osn users are reheating and therm. furnaces. Application in these furnaces natural g. instead of others it is specific fuel it makes it possible to reduce the cost of heating, to improve its quality, to increase efficiency of furnaces and to create more favorable the dignity -gigiennc. of condition in productions, accomodations. In the fuel balance of the power stations OF THE USSR specific weight natural g. composes ok. 20%. Application of natural g. at the power stations gives it means, effect. Efficiency of boiler installations at the power stations with the transfer from the solid to the gas fuel- increases by 1 - 4%; it decreases by 21-26% quantity of service personnel. Summary reduction in the fuel consumption due to the increase efficiency and reduction in the expenditure of electric power for sobstv. need it composes 6-7%. Combustion g. in the furnaces it is boiler small productivity increases efficiency in comparison with the boilers, which use the solid fuel, by 7-20% (depending on the type of fuel) it makes it possible to increase to proizv'oditelyyust' to 30% and more. Use natural g. opens great possibilities for creating the simple, less metal-consuming and more economical it is boiler (steam and water-heating), that work on natural G.

Some g. are at the same time source material for the technological processes in the chem. industry (of them it is manufactured by ok. 200 it is specific razldc- chem. products); on natural g. works a number of largest khimnch. of the combines OF THE USSR.

From the number g., the agents utilized as khimnch., air (atmospheric or enriched by oxygen) and oxygen obtained the widest use in the metallurg., khimich. and the adjacent with them branches of industry (seeAir and oxygen in the technology). Great significance they have also many other g.: acetylene, chlorine, fluorine and rare G.

With torch welding of larger partly is used the flame of acetylene-oxygen mixture, which makes it possible to develop the very high temperature (ok. of 3200 °S). Sometimes the atomic-hydrogen welding, based on heating of metal by hydrogen, converted into the atomic state under the action of electric arc, uses.

The hot working of metals in the furnaces they frequently accompany by the action of chem. agents, which are been in a gaseous state. Saturation of the surface layer of steel by carbon (see cementation) is produced by way it lasts, its heating in the atmosphere g., which dissociate with the isolation of atomic carbon. In industr. type installations for the gas carburizing they use: natural g., butanepropionic mixture, etc. to avoid the excessive isolation of soot (or sludges) to these g. mix generator gas or the flue gases, purified of carbon dioxide it is water vapor.

G. as chem. agents adapt also in the practice of the chemically- therm. treatment of the surface of steel with its nitration, the cyanidation, the aluminizing, chromium-plating , etc. with the gas carburizing of steel by aluminum (or chromium) of it tyuey nagrevayut in the vapors of chloride aluminum (chromium). Nitrogen, generator gas from the anthracite either the charcoal, products of combustion some g. (after the removal of them of carbon dioxide and it is water vapor) and products of ammonia disassociation in Me-talloobr. industry serve as the special atmosphere for dealing with oxidation and decarbonization of the metals, which occur with their heating in an atmosphere of air or flue gases.

As the inert substances for the scavenging of dangerously explosive equipment (gas holders, gas-scrubbing boxes, communications, etc.) use water vapor, carbon dioxide and nitrogen, and also the mixture of carbon dioxide with nitrogen, for example, the products of combustion of the gaseous fuel, burnt with the small excess air. The tech. apparatuses of great capacity are blown through by the inert gases before their filling g. (for example, by hydrogen). In this case air located in the apparatus atm is displaced and is prevented the formation of explosive g. - air.

In the electric-lamp industry for the filling of incandescent lamps adapt nitrogen, krypton, xenon and other filling of incandescent lamps with inert gas decreases the rate of evaporation of thread and thus the period of the service of lamps increases. Use for these purposes some rare g. allows considerably (to 30%) to increase the luminous efficiency of incandescent lamps, which has great significance, since on the needs of illumination is expended ok. 20% of entire manufactured in THE USSR energy. The filling of incandescent lamps with argon-nitrogen mixture widespread, the especially suitable fillers are krypton and xenon, that possess high density and minimum thermal conductivity.

G. adapt also for the intensification of some biokhimich. of processes. Carbon dioxide and clean products of combustion of nonsulfurous fuel can be used as the carbonate fertilizer. The increased carbon-dioxide content (to 0,3% ) in the atmosphere of hot-houses and hothouses accelerates increase and increases the fruiting of some plants. Ripening of the torn away vegetables and fruits (tomatoes, apples, etc.) it is possible to accelerate by their storage in an atmosphere of ethylene.

As the heat-transfer agents they are widespread track. G.: products of combustion (smoke G.), air is thinner the gaseous products of ekzotermich. of processes (oxidation of ammonia, obtaining sulfuric anhydride, etc.). Flue gases as heat-transfer agent uses: for the nepo- means of the heating of articles or materials in the furnaces and the drying apparatuses; for obtaining and preheating of intermediate heat-transfer agents (water vapor, hot water, air, etc.). For regulating the process of heating by flue gases it is possible to dilute them by air or waste gas. Sometimes flue gases serve for the transport of carbon dust and its partial drying in the suspension. In these cases flue gases are not only heat-transfer agent, but also phys. by medium for the transfer of solid bodies, which are been in a powdered state. Air as an intermediate heat-transfer agent uses when is inadmissible the pollution of the nagrevayemogo product by soot and by ashes, that are contained in the some flue gases. Most frequently air as heat-transfer agent adapts in the drying apparatuses and in some heating systems of accomodations.

As the work substances for the accomplishment of the mech. work Of g.rasprostraneny in the gas turbines, in the firearms, in the jet engines and the projectiles, and also in the engines vnutr. of combustion. G., which have low density, are used for the filling of dirigibles and balloons.

The elec. discharge in g. (or pairs) widely adapts in electrical engineering for the rectification of alternating current, transformation of direct current into the variable, the generation of elec. fluctuations, illumination by luminous gas lamps and many others by the selection of the corresponding gases or steam metals it is possible to increase the emission of luminous gas lamps in the assigned region of the spectrum. By this an increase in the general luminous efficiency of luminous source (see the electrical discharge through gases, vacuum tube lamp) is achieved.

Lit.: Kortunov A. K., The natural gas industry OF THE USSR, M., 1967; Speysher v. A., the combustion of gas at the power stations and in the industry, 2 publ., M., 1967; Use of gas in the industrial and power plants, in the collection: Theory and the practice of the combustion of gas, in. 3-4, l., 1967 - 68; Ryabtsev i. i., is Volkov AU, the production of gas from the liquid propellants for the synthesis of ammonia and alcohols, M, 1968. In. A. speysher.