GB303167A - - Google Patents

Abstract

303,167. Barrett Co., (Assignees of Millers, S. P.). Dec. 29, 1927, [Convention date]. Condensing processes; pitch.-Low and high carbon tars are separately condensed from gases collected separately during early and later portions of the coking operation in coke oven or other coal distillation plant. A coke oven plant has two collector mains 3, 4, the uptake 2 from each oven &c. having valves 5, 6 for connecting it with one or other of the mains. Cross-over mains 7, 8 lead to multipass water-cooled condensers 11, 12 of indirect type. The mains 3, 4 are supplied with admixed tar and ammonia liquor through pipes 15, 16 and the mains 7, 8 with ammonia liquor through spray pipes 9, 10. Tar and ammonia liquor escape from the collector mains through pipes 19, 20, and may be pumped back to the appropriate mains, excess tar being collected in wells 21<1>, 22<1>, and pumped to storage tanks 23, 24. Tar or tarry oils thrown down in the crossover mains are passed to decanting vessels 29, 30, separated from ammonia liquor and stored in tanks 29<1>, 30<1>. The light tars or tarry oils from the condensers are discharged into decanting vessels 39 - - 42, similarly separated from ammonia liquor and stored in tanks 43 - - 46. In a modification, condensate from each pass may be separately treated. In an example to obtain a low carbon tar, gases from the first third of the coking operation are passed through main 3 and the remainder through main 4. A high carbon tar may be obtained by collecting the gases from the last third of the coking period in main 4. In either case tar recovered from the collector main is relatively heavy and the lighter tar or oil from the condensers may be employed separately or blended with the heavy tar or other products. A single condenser may replace the condensers 11, 12 when a single tar or tarry oil fraction is required. Or direct contact condensers in which water or ammonia liquor is sprayed into the gases may be employed. Modifications of the plant to obtain both a low and a high carbon tar or several tars comprise the provision of three or more mains. Thus gases from an initial period and a final period may be collected in two of the mains and the remaining gases directed into the third main from which intermediate tars are obtained. In one form a coke oven battery is divided into three sections each having two collector mains, three of the mains being independently operated to obtain varying high or low carbon tars, and lighter tars of varying character being obtained in two condensing systems each of which is connected to three mains. Specifications 289,378, 303,163, 303,164, and 303,165 are referred to. Reference has been directed by the Comptroller to Specification 17494/01.