... 85% according to the difference of boiler type.FuelCoal, water gas, city gas, mixed gas, light oil, heavy oil, residual oil ... fusionFat: decomposition, deodorization, distillation of aliphatic acid, heating, hydrogenation, esterification.Petrochemical: rectification, heating, thermal insulationPlastic&Rubber: hot-press, calender, extrusion ... below 350°C. horizontal oil fuel (gas) heating furnace