According to fuel, there are mixed-firing kilns, which burn solid fuels such as coke, coke powder, coal, etc. Japanese kiln. Gas-fired kilns include burning blast furnace gas, coke oven gas, calcium carbide tail gas, producer gas, natural gas, etc. According to the kiln shape, there are vertical kilns, rotary kilns, sleeve kilns, West German Vimaster kilns, Maerz kilns (Switzerland), Fokas kilns (Italy), etc. At the same time, there are positive pressure operation kilns and negative pressure operation kilns. Linzhou Modern Technology Center has developed and designed mixed-fired kilns with a capacity of less than 300 cubic meters and gas-fired kilns with a capacity of less than 140 cubic meters, especially the XD-type energy-saving and environmentally friendly lime kiln that burns blast furnace gas and coke oven gas. The combustion problems of high calorific value and short flame of coke oven gas are overcome, and the remaining coke oven gas can be fully utilized. The original coke oven gas "lit the sky lanterns", which polluted the environment, has become a valuable energy source that creates benefits for enterprises. It is a very effective way to save energy, protect the environment and increase efficiency for small and medium-sized steel companies, coking companies, calcium carbide companies, and refractory materials industries.