Heat utilization characteristics of industrial furnace
Heat utilization characteristics
The heat utilization methods of the same process and object are different from each other. In the brick kiln furnace, the fuel and workpiece are placed alternately. While the fuel is burning, it will also transfer heat to the nearby workpiece. There are also brick (porcelain) kilns and drying kilns, which mainly rely on radiation and convection to realize heating.
Industrial furnace is both combustion equipment and heat transfer equipment. Obviously, combustion and heat transfer play an important role in heat utilization. The thermal process of kiln includes internal heat exchange, external heat exchange, combustion process and gas flow process in kiln. The combustion process directly affects the output, quality and fuel consumption of products. The precondition to improve the thermal performance of kiln is to improve the combustion process and discharge efficiency. Its essence is the application of combustion technology, so we should master the characteristics of furnace combustion. Analyze the characteristics of the combustion process, reasonably organize the gas flow process and fuel combustion process, and control the emission of products to prevent environmental pollution.
In industrial furnaces, heat transfer modes include conduction, convection and radiation. The heat transfer in furnace is a complex physical and chemical process combined with many heat transfer modes. In a furnace where fuel and materials are co fired, heat can be directly transferred from combustion to materials through heat conduction. Therefore, the particle size and mixing degree of fuel materials have an important impact on heat transfer. Convection is a very important heat transfer mode for most industrial furnaces. High temperature flue gas washes the heating surface and continuously transfers heat to materials or workpieces. The composition, flow direction, flow velocity and heating surface shape of flue gas will have a great influence on the convective heat transfer coefficient. In industrial furnace, fuel, flue gas and furnace body are in high temperature state, so there will be strong radiation heat transfer. There are many factors affecting the effect of radiation heat transfer, such as radiator temperature, angle coefficient, gray coefficient and so on. Reasonable design greatly improves the effect of radiation heat transfer.