Process and system for recovering base oil from lubrication oil that contains contaminants therein

Abstract

A process of recovering base oil from lubrication oil that contains contaminants therein, the process comprises the steps of: (i) extracting a light diesel fraction from the lubrication oil; and (ii) distilling the lubricating oil under vacuum conditions after said extracting step (i) to obtain a base oil that is substantially free of said contaminants.

1 . A process of recovering base oil from lubrication oil that contains contaminants therein, the process comprises the steps of:
 (i) extracting a light diesel fraction from the lubrication oil; and   (ii) distilling the lubricating oil under vacuum conditions after said extracting step (i) to obtain a base oil that is substantially free of said contaminants.   
     
     
         2 . The process as claimed in  claim 1 , wherein the distilling step (ii) comprises molecular distillation. 
     
     
         3 . The process as claimed in  claim 2 , wherein said molecular distillation comprises multi-stage molecular distillation. 
     
     
         4 . The process as claimed in  claim 3 , wherein said multi-stage molecular distillation is performed from two to five stages. 
     
     
         5 . The process as claimed in any one of  claim 3  or  4 , wherein the temperature in each stage is increased sequentially. 
     
     
         6 . The process as claimed in any one of  claims 3  to  5 , wherein the pressure in each stage is decreased sequentially. 
     
     
         7 . The process as claimed in any one of the preceding claims, wherein the extracting step (i) comprises removing of non-light diesel from the light diesel fraction to obtain a substantially pure light diesel fuel. 
     
     
         8 . The process as claimed in any one of the preceding claims, further comprising the step of removing at least part of said contaminants from the lubrication oil before said extracting step (i). 
     
     
         9 . The process as claimed in  claim 8 , wherein said removing step comprises at least one of sedimentation, precipitation, centrifugation, dehydration, deodorization and chemical treatment. 
     
     
         10 . The process as claimed in any one of the preceding claims, wherein at least 85% by weight of said base oil is recovered. 
     
     
         11 . The process as claimed in any one of the preceding claims, wherein said light diesel fraction comprises petrol. 
     
     
         12 . A system for recovering base oil from lubrication oil that contains contaminants therein, the system comprises:
 an extractor for extracting a light diesel fraction from the lubrication oil; and   a distiller for distilling the lubricating oil, after said light diesel fraction has been extracted therefrom, under vacuum conditions to obtain a base oil that is substantially free of said contaminants.   
     
     
         13 . The system as claimed in  claim 12 , wherein the distiller is in fluid communication with said extractor. 
     
     
         14 . The system as claimed in  claim 12 , wherein the distiller comprises a plurality of molecular distillation units. 
     
     
         15 . The system as claimed in  claim 14 , wherein said distiller comprises two to five molecular distillation units. 
     
     
         16 . The system as claimed in any one of  claims 12  to  15 , further comprising a dehydrator for removing water from the lubrication oil that contains contaminants therein, before said lubrication oil is being fed into the extractor. 
     
     
         17 . The system as claimed in any one of  claims 12  to  16 , further comprising a filter for removing solid contaminants from the lubrication oil that contains contaminants therein, before said lubrication oil is being fed into the extractor. 
     
     
         18 . The system as claimed in any one of  claims 12  to  17 , further comprising a precipitator for precipitating contaminants from the lubrication oil that contains contaminants therein, before said lubrication oil is being fed into the extractor. 
     
     
         19 . The system as claimed in any one of  claims 12  to  18 , further comprising a centrifugator for centrifuging solid contaminants from the lubrication oil that contains contaminants therein, before said lubrication oil is being fed into the extractor. 
     
     
         20 . The system as claimed in any one of  claims 12  to  19 , further comprising a deodorizer for removing odor from the lubrication oil that contains contaminants therein, before said lubrication oil is being fed into the extractor. 
     
     
         21 . The system as claimed in any one of  claims 12  to  20 , further comprising means for generating vacuum conditions in said distillation unit. 
     
     
         22 . The system as claimed in any one of  claims 12  to  21 , further comprising a condenser disposed within said distillation unit for condensing the base oil which is substantially free of said contaminants.