| 摘要 |
1,165,469. Thermal cracking. LINDE A.G. 11 Oct., 1967 [12 Oct., 1966], No. 46352/67. Heading C5E. In a process for thermally cracking hydrocarbons, e.g. benzine, to produce olefins in a cracking furnace comprising a convection zone and a radiation zone, wherein a hydrocarbonwater vapour mixture is initially heated in the convection zone through which pass hot flue gases leaving the radiation zone, and is then cracked in the radiation zone which is heated by hot combustion gases, the transition temperature of the feed between the convection zone and the radiation zone is regulated by controlling the heating in the convection zone. Said control may be effected by one of the following means:- (a) part of the hot flue gases leaving the radiation zone may be diverted so as not to flow through the convection zone; (b) part of the feed mixture may be allowed to by-pass at least part of the convection zone, being reunited with the remainder before the radiation zone; (c) the hot flue gases flowing through the convection zone may be cooled, e.g. by indirect heat exchange with water flowing through tubes within the convection zone. |
