DISCUSSION WITH DR. PIER
The discussion with Dr. Pier was concerned chiefly with his reminiscences on the early development of the coal hydrogenation process and on some of the work on dry coal hydrogenation process and on some of the work on dry coal hydrogenation. The work with dry coal was of an orienting nature and they were never able to get an entirely satisfactory continuous plant operating. In some of their early experiments with brown coal, they produced 35% middle oil, 55% gatch (wax), and 15% gas at 200 atmospsheres pressure. The work was done in an apparatus in which coal was fed into the reactor by a plunger-type pump and high pressure valves. Subsequently, Dr. Wissel at Wesseling started that this coal pump was never very reliable and the operation that Pier referred to would be extremely hazardous in a large scale plant. Another attempt at simulated dry coal hydrogenation was made in a 300-liter converter by spraying a mixture of coal and benzene through nozzles into the converter. The hydrogen was heated considerably above reaction temperature in order to supply heat for vaporization of benzene and heating the coal to reaction temperature. This unit never operated satisfactorily and no measurements were possible. Pier suggested the use of a tilting-type autoclave in studying the hydrogenation of coal at short times of contact. This technique has been used successfully in some of their early work on hydrogenation of shale oil. The sample was kept in the cold end of an autoclave. The autoclave was then tilted and the sample dropped into the other end at reaction temperature. The reverse procedure was used to quench the reaction.
At present there is apparently no significant development work in progress on hydrogenation in Germany. In the Western Zone the plant at Wesseling is being operated for Shell to hydrogenate straight run residue to produce gasoline. A similar operation is being performed at Gelsenberg for Socony Vacuum and Esso Standard.