GB127700A - Improvements in or relating to the Continuous Dehydration and Distillation of Tar, or other Liquids and to Apparatus therefor. - Google Patents

Abstract

127,700. Wilton, T. O. May 28, 1918. Progressive evaporators; hydrocarbons, distilling. - Tar and other liquids are dehydrated and distilled by passage through a series of units each consisting of a coil in which the liquid is heated to a suitable temperature under pressure, and an expansion chamber in which the pressure is suddenly released so as to produce vaporization of the lighter constituents. The tar is preheated, and is pumped, under a pressure of 30-50 lb. per sq. in., through a coil 1 heated to 160-190‹ C. The heated tar enters an expansion chamber 3 through a spring-relief valve, and the reduction of pressure causes the water and light oils to vaporize. The vapours escape by a pipe 8 to condensers 9, 14 in which light oils and naphtha respectively are collected. The residues are pumped, under a pressure of 30-50 lb. per sq. in., through a coil 2 heated to 230-300‹ C., and enter an expansion chamber 4. The resulting vapours are led by a pipe 18 to a first creosote condenser 19. The residues are led to a vessel 6 in which dstillation is effected by free steam of about 300‹ C. The vapours are led by a pipe 22 to condensers 23, 28 in which anthracene and second creosote respectively are collected. The residual pitch is led to a cooler 31. The tar is preheated by use as cooling-agent for the condensers 28, 23, 9 and the cooler 31. The heating-coils 1, 2 may be arranged concentrically so as to be heated by the same furnace, the hot gases passing over the coils 2, 1 in succession. Bvpass arrangements under thermostatic control provide for regulation of the temperature.