SU1359628A1 - Method of recovering heat of hot gases - Google Patents

Abstract

Invention m. used in installations working with foam between 1m1 coolant. The purpose of the invention is. increase in the degree of waste heat utilization. To do this, an additional foam containing bubbles of a smaller size than that of the main foam is simultaneously introduced into the foam layer. This contributes to the turbulization of the gas-liquid mixture in the form of a foam and the renewal of the contact of the phases, reducing the diffusion resistance, and allows to increase the coefficient of heat and mass transfer. I il.

Description

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The invention relates to a power system and can be used in utilization plants operating with a foam intermediate coolant.

The aim of the invention is to increase the degree of waste heat utilization by means of heat exchange by intensifying heat exchange.

The drawing shows schematically the installation for the implementation of the proposed method.

The installation contains a channel 1 of hot gases with a perforated plate 2 installed in it, above which a heat-receiving heat exchanger 3 is located.

On the side wall of the channel 1 is installed porous vertical nozzle 4.

The method is carried out as follows.

Hot gas is passed through a perforated plate 2 to which Liquid intermediate heat transfer fluid is supplied. By bubbling through the latter, a main layer of foam is formed with the sizes of bubbles of given sizes, the size of which depends on the installation features, for example, the dimensions of the perforation of the plate 2 and the consistency of the intermediate heat carrier. The heat transfer resistance of waste gases is determined by the laminar boundary layer of the liquid intermediate heat carrier on the surface of the heat-receiving heat exchanger 3 and the boundary layer of non-condensable gases that accumulate during the condensation of water vapor at the heat exchanger 3 surface. additional foam containing bubbles smaller than that of the main foam bubble sizes. The foam bubbles set in motion behave like hard balls that contribute to the destruction of the boundary layers.

gas and liquid at the surface of the heat gQ ablation. To form an additional

the heat exchanger 3, the turbulence of the gas-liquid mixture in the form of foam and the renewal of the contact of the phases, the reduction of diffusion resistances, and consequently an increase in the coefficient of heat and mass transfer. Small foam bubbles, which have a more stable spherical shape than large ones, prevent sticking and contribute to breaking the pain 55

Claims (1)

foams, instead of waste gas, it is possible to use any other gas, for example compressed air, nitrogen, and if necessary, with the addition of a neutralizing sulfur compound, for example ammonia. Invention Formula The method of heat recovery of hot gases by bubbling the last 0 0 bubbles provide stabilization of the foam layer, while simultaneously increasing the surface of contact between the gas and the intermediate heat transfer fluid. Additional foam is created on a porous vertical nozzle 4 installed above the foam layer, irrigated with a film of an intermediate heat transfer medium on the one hand and penetrated by a gas on the other hand. For example, additional foam is obtained on a vertical porous ceramic or metal nozzle 4 with a diameter of 0.10–0.25 mm. At the same time, the tear-off diameter of the bubbles formed in the additional foam is 0.8-1.4 mm, which is 2-3 times less than the tear-off diameters of the bubbles formed in the holes with a diameter of 0.10-0.25 mm on a horizontal plate 2 while gas is bubbling through a layer of heat-transfer fluid. Even with holes in the plate 2, 10–20 times larger than the average diameter of the bubbles in the additional foam will be less than the average diameter of the bubbles with a usual sponge 4-5 times or more. When changing the load on gas and liquid heat carrier in a wide range, the ratios between their flows, going to the formation of a layer of the main foam and an additional one, are adjusted depending on the total load on the gas and the liquid heat carrier and the conditions for the formation of additional foam. Depending on the parameters of the gas and the method of obtaining small bubbles, the proposed method can be implemented using a different scheme. If the waste hot gas contains impurities that clog the pores of the porous nozzle 4, then a portion of the waste gas previously cleaned in the main foam layer is used to form additional foam. At the same time, the total flow rate of the circulating gas — purified and basic unpurified — should ensure the maintenance of a stable foam without splashing. 0 five 0 five five foams, instead of flue gas, it is possible to use any other gas, for example compressed air, nitrogen, if necessary with the addition of a sulfur neutralizing agent, for example ammonia. Invention Formula The method of heat recovery of hot gases by bubbling the last 31359628 through a liquid intermediate heat carrier with the formation of a layer of the main foam with a given size of bubbles, in which a heat-absorbing heat exchanger is immersed, which differs in bubbles smaller than that of the main one in order to increase the degree. fines utilization of waste heat by intensifying the heat exchange and simultaneously giving an additional foam to the foam layer bubbles smaller than that of the main foam. fines utilization of waste heat by intensification of heat and mass exchange, at the same time an additional foam with the size of Editor E. Sligan Compiled by V.Kn Zev Tehred I. Veres Proofreader S. Shekmar Order 6144/42 Edition 612 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and Polygraphic Enterprise, Uzhgorod, st. Project, 4