Investigation of the Intensification of Separation Processes Using the Heat of Exhaust Gases

Abstract

The useful use of heat for the above cases is primarily related to the use of heat from the exhaust gases. It should be stressed that in all cases it is necessary to return the maximum amount of waste heat to the process. Part of the heat is usually returned to the working chamber with heated air (up to 300 - 500 oC). In some cases, it is possible to use a certain amount of gas heat for drying and heating the raw material, the finished product and/or for heating the process water used in the processing; the use of heat from gases to produce steam and other parameters for the necessary heating of the blast furnace. All of this opens up the possibility of achieving very high end results for energy plants. However, as a rule, the exhaust gases are characterized by fairly high concentrations of fine solid particles (fine removals), which must be effectively removed in the separator because in most cases they prevent the efficient use of heat from the exhaust gases. Thus, efficient separation of fine removal is crucial for heat recovery of exhaust gases, especially for high-performance units. The ways to intensify the separation processes in industrial waste were investigated and made practical conclusions. Based on known literature data and results of own experiments, some questions of separation of fine removal are considered. The basics of the separation mechanism are formulated, which are reduced to elucidating the causes and patterns of movement of small particles to the separating surface across the main stream. The mechanisms of separation of small particles due to turbulent diffusion are analyzed in detail, the possibility of realization of the mechanism of separation on the basis of thermophoresis is estimated. The initial parameters and criteria that characterise the particle separation process have been established. A formula for assessing the particle separation rate is derived and the effect of the specified criteria on this value is analyzed. The analysis of the above dat a resulted in practical conclusions on ways to intensify the separation processes under industrial conditions.