A FLOWING SOLVENT REACTOR FOR COAL-LIQUEFACTION WITH DIRECT ELECTRICAL-RESISTANCE HEATING

A flowing solvent reactor for coal liquefaction has been developed, which uses direct electrical resistance heating of the reactor tube wall to achieve rapid, controllable heating. A computerized control system previously developed for a wire-mesh pyrolysis apparatus is used for temperature control; heating rates between 0.1 and 10 K/s, peak temperatures up to 450-degrees-C, and isothermal holding times from 5 to 1600 s have been obtained. Alternating current is used for heating, allowing a simple thyristor bridge to be used for power control. Solvent is fed from a pressurized reservoir at up to 100 bars, obviating the need for a supply pump. Using this apparatus the effects of a variety of parameters on primary coal liquefaction processes can be examined; the design of the system and typical results are presented.