Recycling of Waste Generator Oils by Different Treatment Methods

Abstract

Engine oils with wide range of viscosities are used to lubricate an engine’s moving parts in different industrial units. Used engine oils are considered hazardous wastes because of their high content of pollutant ,thermal degradation products from the base oil and additives and combustion products from fuel and lubricant. The used oil still contains a large proportion of valuable base oil that may be used to formulate new lubricants if undesirable pollutants are separated from the oil by an appropriate recycling method. Different techniques have been practiced for recycling used lubricating oil but not the generator oil. Because of the large amount of electrical power generator oil use in our country we have to look for a practical and effective method about how to recycle waste generator oil. In this study, we applied different recycling procedures, i.e., vacuum distillation, acid/bentonite, distillation/bentonite, and acid/distillation treatments. The treated waste generator oil was evaluated by comparing the change in physical and chemical properties including specific gravity, viscosity, pour point, flash point, ash content, and total acid number before and after treatment. In comparison, the results obtained from the evaluation of physical and chemical properties of the waste and fresh generator oils show that all the treatment methods show varying degrees in improvement of their properties and that the best results are obtained from the recycling treatment (acid/bentonite) method.

Keywords: Lubricating oils, refining, recycling of waste oil, environmental pollution, generator oil, used oil