... for regenerating the black waste oil, including waste engine oil, lube oil, hydraulic oil, gear oil, dirty diesel oil, mixed oils etc. HCY ... environment pollution. HCY Heating device are optional, there are oil-burner furnace, natural-gas furnace, also you use the coal ... produce different density diesel fuel oil. 2, HCY Heating device are optional, there are oil-burner furnace, natural-gas furnace, ...