Factors influencing the liquefaction,separation,and recovery of solid grease from restaurant garbage

The recovery of oil from the restaurant waste was studied experimentally to identify the effects of temperature and heating time in the hydrothermal process,the height and type of the coalescent material in the packed-bed coalescer,the temperature of the oil-water mixture effluent,and the water flow velocity at the coalescer inlet.The results show that the optimal hydrothermal process conditions for solid grease liquefaction and extraction are heating for 80 min at 160℃.For the coalesce treatment,the coalescent made of plastic fiber was more effective for oil and grease recovery than that made of metal wire.The packed bed coalescent should be 35 cm height with an optimal temperature of the oil-water mixture being 40℃.Reducing the water flow velocity at the inlet of the packed bed coalescer increases the oil and grease recovery rate with 75% oil recovery at velocities below 0.825 m/s.