| 摘要 |
<p>1517244 Vertical retorts J W HOLLAWAY 24 March 1976 11813/76 Heading F4B In a vertical retort 32 for carbonizing coal having heating walls 34 through which heat from heating flues 36 is transmitted to the retort interior, the heating walls 34 have a constantly decreasing thickness from their lower to their upper ends. Coal gas produced in the retort is passed through a condenser 66 to remove tar oils therefrom and thereafter recirculated into the bottom of the retort via a heat exchange zone 42 in which it passes in countercurrent heat exchange relationship with the discharging coke. Part of the coal gas may be bled via a connection 72 and fed, together with preheated air in a line 70, into the top of the heating flues wherein it is burned, said air being preheated in a tubular heat exchanger 48 by means of waste gases leaving the bottom of the heating flues 36. The heating walls 34 are formed from castable refractories which incorporate high alumina cement and heat resistant aggregates, the interior of said walls being lined with stainless steel cladding 40. The heat exchange zone 42, which is defined by an extension of said cladding 40 terminates in a trough 44. In an alternative embodiment (Figs. 1 and 2, not shown), the coal gas withdrawn from the retort is fed through conduits (30) into the lower portion of the heating flues (18) where it is burned. The cross-section of each heating flue increases as it extends upwardly.</p> |
