... driving device, supporting device and sealing ring.3. Can I use the coal or gas as the heating source ... ?Yea, you can use coal, gas, electricity, oil and wind ... , heated air duct, inlet month and furnace body and other structure. 2. The fuel can be coal, fire, gas ... , and electricity and other fuel. 3. We can design the gas generator furnace, firebox, and euipped elevator ...