| 摘要 |
<p>The parent patent described the regeneration of used lubricating oil consisting of pulverising the il in a pulsed form, at the top of a first column into which propane is introduced in countercurrent. The mixt. of oil propane and oil dissolved in propane is passed through a series of columns at the top of at least one of which additional propane is pulsed in countercurrent. At the base of the columns impurities deposited by gravity are removed and the purified oil is recovered by vaporising the propane. Pref. the columns are vibrated mechanically and the propane is liquefied for re-use. In the addn. patent before the treatment is commenced the used lubricating oil is injected into a reservoir contg. liquified propane and is left there long enough for an intimate mixt. to be formed and impurities to be deposited. The procedure of the parent patent is then followed. The oil is injected at different levels into the reservoir for pref. in the ratio of from 1:4-1:8.</p> |
