174 / 222
البحـث الثاني
167
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
44
The simplified process flow diagram is illustrated in Figure 25.
Figure 25 MRD simplified process flow diagram
Source: Speight et al (2014)
5 Comparison of available technologies
In light of the foregoing technology review which covered only some technologies
which have found their way into commercial application, it can be seen that these
technologies, albeit consisting of different unit operations, are all based on a sequence of
steps which can be grouped under three main heading: Primary treatments, secondary
treatments and finishing treatments. The process always starts with a primary
treatment, followed by a secondary treatment and finally a finishing (tertiary)
treatment. Full details of the various treatments are provided in Audibert (2011). A brief
overview is given below:
Storage
tank
Solvent
Light ends
and Water
Light
heating oil
Feed
Atmospheric
distillation
Multistage
distillation
Bottoms
product
Liqui-liquid
extraction
Extract
Thin film
evaporator
KOH
solutio
Distillation to
remove solvent
and to storage