
91
4
Composition and
Treatment
4.1 INTRODUCTION
Large quantities of used oil are generated each year, which, if properly collected and
processed, can be a valuable energy source or rened to produce usable products
such as new lubricating oil. However, used oil is contaminated with water and other
liquids, halogens, and other elements including heavy metals. It is not surprising
that, in most countries, it is regarded as potentially hazardous waste and must be
handled, processed, and stored appropriately. The transport, storage, and ultimate
use of used oil is governed by a variety of direct and indirect national and interna-
tional legislation ...