| 摘要 |
<p>Used plant oils are continuously processed to remove saturated fatty acids, mineral oil components and water, thus recovering usable lubricating and hydraulic oils. Continuous processing of used plant oil comprises: (a) feeding the used plant oil m0 with solvent m12 consisting of 90 % acetone and 10 % cycloheptane (ratio m0/m12 of 0.5) through nozzles D1 and D2 using pump P1 producing free streams of high impulse and forming an emulsion m2 made of 1st lighter phase rich in unsaturated fatty acids and a 1st heavier phase rich in saturated fatty acids and impurities; (b) separating emulsion m2 into lighter phase m3 and heavier phase m4 by centrifuging, and cooling to 4 [deg]C forming a 2nd lighter phase and 2nd heavier phase, which are separated from each other in vessel B5; (c) vaporizing 2nd heavier phase m6, cooling and removing as product m11; (d) cooling heavier phase m4 to 0 [deg]C forming a 3rd lighter phase and 3rd heavier phase, which are separated from each other in vessel B6; (e) combining 2nd lighter phase m5 and 3rd lighter phase m7 to a mass stream m9 and feeding to rectification column KE between packings PA1 and PA2; and (f) withdrawing the sump product (saturated fatty acids and impurities) using pump P3 whilst the head product m12 consisting of purified solvent is recycled to the cycle stream. An independent claim is also included for the apparatus for continuously processing used plant oil.</p> |
