Issue 161-M

172

2016

أوابك العلمية لعام

�

ص لبحوث العلمية الفائزة بجائزة

�

عدد خا

مجلة النفط والتعاون العربي

161

العدد

- 2017

أربعون

المجلد الثالث و ال

Re-refining of Used Lubricating Oil and its Economic and Environmental Implications

6 Environmental implications of re-refining of used lubricating oils.

Used oils are characterized as hazardous wastes under Basel convention and, therefore,

must be handled in accordance with the provisions thereof. Their disposal in the

environment is dangerous for the natural systems, be it water, land or air. Initially

theses waste oils were either discarded in landfills or burned to recover energy. Both

disposal methods were considered, and rightly so, to be harmful to the environment. In

the 1970s, growing environmental concerns in industrialized countries have favored the

re-refining option over these recycling methods. There have been several studies in

recent years to assess the implications of re-refining of used lubricating oils on the

environment through a specific process called LCA (Life Cycle Assessment).

Briefly, an

LCA is a study based on the review of the environmental impacts of a product

throughout its life cycle. It is a widely accepted framework that is used to assess the

environmental impact of a given product or process. As far as used lubricating oil is

concerned, many studies have been conducted to assess its potential impacts on the

environment (Vold et Al, 1995; GEIR, 2005; IFEU, 2005; OECD, 2006; CAL, 2013). In

these studies, re-refining was compared to the combustion of used oil as fuel with

energy recovery. These studies have demonstrated that substantial environmental

improvements can be obtained by re-refining used lubricating oil instead of burning it

for energy recovery.

Vold et al (1995) have reported that re-refining of used lubricating oil reduces the

potential environmental impact in relation to the burning of waste oil, in particular the

contribution to acidification and global climate change are reduced.

As illustrated in Figure 26, re-refining used lube oil to lubricants emits less atmospheric

pollutants (CO2 emissions are 40% lower) and consumes less energy (66%) than the

refining of crude oil into lubricants.