GB1449760A - Method of recovering thermal energy in a gas production process - Google Patents

Abstract

1449760 Dry cooling coke; preheating WAAGNER-BIRO AG 26 July 1974 [6 Aug 1973 14 Aug 1973] 33236/74 Headings F4B and F4G In a gas production process heat for drying and/or preheating the coal charge is recovered by cooling the coke produced in a closed primary inert gas circuit, utilising this primary gas circuit to heat a secondary circuit and utilising the inert gas in the second circuit to dry and preheat the coal, dust being separated from both gas circuits. As shown, a coke dry quenching chamber 2 has a primary inert gas circuit including a dust separator 6, heat exchanger 7, dust separator 8 and blower 5. The secondary inert gas circuit includes a heating element 11 in heat exchanger 7 supplied with gas through pipes 9 and 10 controlled by valve 40, a preheater 12, cyclone 13, drier 14, cyclone 15, blower 16, dust separator 17, return pipe 19 with valve 39 and waste pipe 18 with valve 38. By closing valves 38 and 40 and opening valve 39 a closed circuit is obtained and by closing valve 39 and opening valves 38 and 40 an open circuit is obtained. A further heating element 23 in the heat exchanger 7 produces hot gas used to generate steam or for another utility. Preheated coal collects in a chamber 22 and dried coal is fed by line 21 to the preheater. Fine coke and coal dust is collected in a mixer 41 which feeds it to chamber 22 with the addition of a binder. In a modification (Fig. 2) the drier 26 incorporates a fluidised bed and another modification (Fig. 3) has both drier and preheater operating on the fluidised bed principle. A final modification (Fig. 4) has the secondary inert gas circuit passing through a coke oven regenerator. The inert gas may be nitrogen.