... operate 2.Automatically temperature-testing 3 Low fuel consumption Coal Fired Type Air Heater Applicable Range:1. Processing and drying for chemical, ... , heavy oil.3.Gas fuel---like coal gas, natural gas, liquid gas.Types:1.Directly Heating FurnaceThe hot-blast air which generated ... , like milk powder, synthetic resin. This heating device heats air by various forms of heat exchanging. The larger of the ...