GB680545A - An improved manufacture of gases from carbonaceous materials - Google Patents

Abstract

680,545. Gasifying powdered fuel. ARNOLD, J. C. (Standard Oil Development Co.). July 12, 1950 [July 27, 1949], No. 19793/49. Class 55 (i). Gas mixtures rich in carbon monoxide are produced by subjecting a fluidized mass of subdivided carbonaceous solids to combustion with upwardly flowing oxygen-containing gas in a heating zone at a temperature above the minimum gasification temperature, and passing the heated solids suspended in a gasification medium through a transfer line reactor, e.g. as described in Specification 625,523, the length of reactor and suspension velocity being correlated to provide for the conversion of most of the medium to the carbon monoxide-containing mixture in the line reactor. Air or other combustion supporting gas is admitted through a line 1 to a heater 10 containing a fluidized mass of coke particles, secondary air being introduced through tuyÞre 5 to prevent reduction of CO 2 formed. Hot gases after passage through a steam superheater 9 may be recycled through the heater as a control in heat generation. Coke at 1800‹- 2200‹F. is withdrawn into a line 13 and conveyed by superheated steam through a transfer line reactor 15 to a generator 20 in which a fluidized bed of residual coke is maintained by product gas and unconverted steam. Further steam CO 2 or air may be supplied through a line 16. About 60-85 per cent of the steam supplied to line reactor 15 may be converted therein, the temperature at the generator inlet being about 1750‹-1850‹F., and the contact time in line 15 and generator being e.g. 2-6 and 4-10 seconds respectively. Solid particles at 1700‹F. return to the heater through a line 24, make-up coke being admitted from a store 28 to the heater, generator or line 15. Hydrocarbons may be supplied to generator 20. Pressures below or above atmospheric may be employed : in synthesis gas production the pressure is preferably the same or slightly higher than the synthesis pressure which may be 700 1b. per sq. in. Non-fluidizable packings may be provided in the heater and generator.