properly sloped having an outlet tube 26 an oil outlet tube 211 and an oil inlet tube 212 an overflow tube 213 and passageway tubes 214 and 215 on the top oil soaked waste pieces are liquefied and dissolved at temperatures of 200 u00b0 370 u00b0 c for 30 minutes when moving in the converter 2 the oil sealed residue conveyor 3 has a similar structure as the oil sealed feed conveyor 1 having a feed inlet tube 31 a housing 32 a screw 33 and a motor 34 combined together the housing 32 has an outlet 321 an inlet 322 an oil outlet tube 323 an oil inlet tube 324 and an overflow tube 325 the oil sealed residue conveyor 3 washes and separates residue inorganic wastes after liquefying process while moving in the housing 32 the soaking oil control device 4 consists of a heavy oil storage tank 41 a heavy oil drum 42 a passageway solid liquid separating control set 43 and liquid pumps 44 45 and 46 the heavy oil drum 42 is connected with the feed tube 12 to feed oil in the oil sealed feed conveyor 1 and keep the oil therein at a constant level together with operation of the liquid pump 46 and the passageway solid liquid separating control set 43 so that the wastes moving in the oil sealed conveyor 1 may be soaked in oil and insulated from air for continuous subsequent operations the converter oil control device 5 consists of a fire heater 51 a hot oil drum 52 a mixed heavy oil storage tank 53 a heavy oil cooler 54 a passageway solid liquid separating control set 55 and liquid pumps 56 57 the hot oil drum 52 is connected with the oil outlet tubes 133 211.