مجلة النفط والتعاون العربي
161
العدد
- 2017
أربعون
المجلد الثالث و ال
2016
أوابك العلمية لعام
�
ص لبحوث العلمية الفائزة بجائزة
�
عدد خا
24
14
Since the early days of this century, the lubricants technology continued its
advance to develop products that are capable of meeting the rising demand for
lubricants and more importantly to improve performance and reliability.
Naturally, the increased use of lubricating oils generated the problem of the used
oil and how to get rid of it especially that drain intervals were relatively short. In
the beginning dumping in the environment was the case that environmental laws
and regulations were hardly in existence anywhere. It is not known when any
commercial activity was made to use waste lubricating oils but it must have been
limited and for the use of the waste as fuel only and before the advent of re-
refining came into play.
However, the first re-refining activities were reported in Germany in 1921
20
, and
later developed into an industry largely on its own. It was also accompanied by
the use of used oil directly as fuel or processed strictly for fuel purposes. At that
time, lubricating oils contained little or no additives, which made their recycling
possible by simple processes involving settling and filtering and then heating to
remove volatile components followed by settling or centrifuging to remove the
remaining insoluables
4
.
During the Second World War processing used oil gained ground for the scarcity
of crude oil resources
4
. The technology developed from simple distillation to acid
clay treatment and so on.
The low oil prices until the early 1970s were not encouraging for the re-refining
industry. However, the sharp increase of oil prices and the start of the tightening
of environmental laws and regulations were the stimulant needed for growth in
recycling and re-refining which to a large extent continues at different pace to
this day.
However, the available processes were found to be increasingly not adequate for
the modern needs of the lubricants manufacturers as they failed to keep pace with
the increasing quality demanded by the market. However, these processes were
not entirely discarded as many investors in the less stringent countries continued
to use them.
For North America, the first hydro-treating re-refiner was the State of North
Carolina as it started a plant using the Phillips Re-refined Oil Process (PROP)
41
where prison inmates were employed as operators and the plant continued to be
used until 1983. The importance of this small plant (250000 gallons annually or