51 / 222
مجلة النفط والتعاون العربي
161
العدد
- 2017
أربعون
المجلد الثالث و ال
2016
أوابك العلمية لعام
�
ص لبحوث العلمية الفائزة بجائزة
�
عدد خا
44
34
Industrial oils are not different. Comparative test life for turbine oils indicates that
it is 4000 hours for solvent refined oil and 18000 hours for hydrocracked oil
32
.
For hydraulic oils the comparative numbers are 2000 and 6000 hours
respectively
32
.
The Impact on Used Oil Re-refining:
It is clear from the evolution of lubricating oil specification and consumption
trends that the used oil re-refining industry has to follow suite in order to be viable
and able to compete. It is often reported that re-refined oils are now on par or
better than virgin oils. But to satisfy the trend of moving away from Group I oils,
only the processes using a hydro-treating step can now compete.
The technological advances in the last 15 years have shown that the re-refining
industry has reached a stage where it can produce re-refined base stocks on par
with virgin base stocks by following the hydro-treating route
54
. Consumer
awareness of the quality of re-refined lubricants is spreading slowly but the
industry still suffers from the stigma that its products are recycled and may be
sub-standard and have to sell at a discount. This issue is particularly important in
developing countries and in other low-cost markets
54
.
The precipitous decline in crude oil prices since June 2014 and the subsequent
decline of base oil prices are not helping the re-refining industry though
regulations in some countries favors re-refined oils.
This is not to say that the more classical processes of distillation and solvent
extraction are now redundant. They still can play a role for small capacity or for
markets that still use lower grade finished lubricants.
The trend to extend the oil drain periods will enhance the re-refining industry to
produce base stocks that are compatible with higher specification though the trend
will reduce the availability of used oil in the long run.