| 摘要 |
<p>Purificn. of used lubricating oil is carried out by (a) removing water and sludge-forming impurities, (b) distilling under reduced pressure in a predistillation column with a short residence time, (c) evaporating under vacuum in two series-connected wiped-film evaporators, the bottoms product from the 1st-evaporator being passed to the 2nd, and (d) subjecting the overhead product to after treatment. The process gives higher-yields and better product quality than the prior art processes.</p> |
