A backlight assembly includes a receiving container, a light-generating unit and a reflective sheet. A three-level prediction algorithm may be performed to obtain auto-precharge prediction for each readwrite request, without having to track every individual page. The advantages of this method include the recovery of a high yield of intact VLPs. The overhead vapor is condensed to produce an overhead liquid of lubricant boiling range hydrocarbons, a portion of which is recovered as a product and a portion of which is recycled.