The function of hot blast furnace is to heat the blast air to the required temperature so as to improve the efficiency and efficiency of blast furnace.It works on the principle of "heat storage".The gas is burned in the combustion chamber, and the high temperature waste gas passes through the grid brick and causes it to store heat. When the grid brick is fully heated, the hot air furnace can be changed to supply air. At this time, the relevant combustion valves close, the supply air valves open, and the cold air is heated and sent out through the grid brick.When three or four hot blast furnaces are installed, two or three are heated, one is supplied with air, and two are heated when they are replaced alternately.
Direct type high purification hot blast furnace
It is the direct combustion of fuel, through high purification treatment to form hot air, and direct contact with the material heating drying or baking.This method of fuel consumption
Fuels can be divided into:
1.Solid fuels, such as coal and coke.
2.Liquid fuels, such as diesel oil, heavy oil, alcohol-based fuels
3.Gas fuel, such as gas, natural gas, liquid gas.
The high temperature combustion gas obtained after the combustion reaction of the fuel is further in contact with the outside air. After mixing to a certain temperature, it directly enters the drying chamber or baking room. It comes into contact with the dried materials, heats up and evaporates the water, so as to obtain the drying products.In order to utilize the heat of combustion reaction of these fuels, a fuel combustion apparatus must be added.Such as: coal burner, fuel burner, gas burner, etc.
This type of direct - heating hot - blast furnace can not be used for farming and other heating.
Indirect hot air furnace
It is mainly used for drying materials that are not allowed to be contaminated, or for drying heat-sensitive materials with low temperature.Such as: milk powder, pharmaceutical, synthetic resin, fine chemical and so on.This kind of heating device, namely steam, heat conduction oil, flue gas as carrier, through a variety of forms of heat exchanger to heat air.
The most essential problem of indirect hot - blast furnace is heat exchange.The greater the heat exchange area, the higher the heat conversion rate, the better the energy-saving effect of the hot blast furnace, the longer the life of the furnace and heat exchanger.Conversely, the size of the heat exchange area can also be identified from the flue gas temperature.The lower the smoke temperature, the higher the heat conversion rate, the greater the heat exchange area.
After the separation of fuel and heating source, can be used for human heating.
