A professional who tends extractor tanks, distilling and condensing units, and auxiliary equipment that removes grease from bones for further processing. Respnsibilities include:

• Loads bones into extractor tanks and bolts tank door, using wrench.
• Turns valves to circulate naphtha and live steam through extractor tanks to dissolve and remove grease from bones.
• Observes tank thermometer and color of vapor through viewing glass to determine when all grease has been removed.
• Turns valves to circulate spent naphtha through distilling and condensing units.
• Starts steam pump to force grease into treating tank.
• Notifies other workers to start and stop screw conveyor that removes degreased bones from extractor.
• Closes top valves and opens bottom valves on extractor tanks to flush naphtha from tank for processing subsequent batches of bones.