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مجلة النفط والتعاون العربي
161
العدد
- 2017
أربعون
المجلد الثالث و ال
2016
أوابك العلمية لعام
�
ص لبحوث العلمية الفائزة بجائزة
�
عدد خا
38
28
Collectors and re-refiners have adopted safeguards and procedures to avoid
having PCBs in their used oil especially that PCB
’
s use has been outlawed as
mineral transformer oil is now advanced enough to do the service without PCB
and its associated hazard.
But remnants in old electric systems do exist and incidents occur. In the US, if
PCBs are found in used oils above the allowed limit, the EPA does not allow even
the dilution
50
of used oil by another to reduce the PCB concentration to less than
50 ppm before re-refining or using it as fuel and forces the companies to destroy
the oil by special incinerators. The US EPA imposed heavy fine on a re-refining
company unless it properly disposes of PCB contaminated oil by end of 2016
43
.
However, the PCB rules in the US are now under review and the anti-dilution rule
may be removed or revised.
Resource Conservation:
Crude oil is a precious resource that is very expensive to find and develop and its
price often high especially for developing countries. Therefore, its conservation
is a priority for most consuming societies.
It is said that it takes one barrel of crude oil to produce the same amount of
lubricating oil that can be obtained by re-refining one gallon (1/42 barrel) of used
oil
1
. Therefore societies need for lubricants could be tied to crude oil refining for
virgin base oils supplemented by re-refining of used oil. Surely, on this point the
cost of re-refining is much less though in refining crude oil we obtain other
needed products as well.
At the same time, re-refining uses comparatively much less energy (one third) to
produce base oils as compared to virgin base oil production.
The process of re-refining can be repeated many times as the oil is changed and
the saving is substantial depending on the collection rate, the yield and the number
of times the used oil is collected. The factor is reported to be more than 30 times
in favour of re-refining over virgin production of base oils
1, 106
.
Burning used oil in certain controlled applications is a form of conservation
because the used oil is substituted for fuel oil, gasoil, natural gas or coal. But this
is limited to only one cycle as compared to re-refining.