On this day in 1891, Frederic Lennard was granted the patent for APPARATUS FOR THE DISTILLATION OF TAR. U.S. Patent No. 459,123.
The object of this invention is to provide means whereby the distillation of tar or other matters which can be distilled according to this invention is effected in a continuous manner, and more rapidly, economically, and efficiently than hitherto.
According to this invention the tar is subjected to distillation to pass in films or streams of but small depth over surfaces which are heated, preferably, with the intervention of a bath of oil or other liquid which can be conveniently raised to and maintained at the temperature necessary for distilling the tar. To insure the effectual working of the still, the tar before being admitted to the still should be raised to such a temperature that distillation commences immediately the tar enters the still. The volatile products are collected as they arise and the pitch passes off at the outlet. Steam should be injected into the still to facilitate the distillation.
