Control system for a coal gasification plant

In an apparatus including a reactor to gasify fine-particle fuels under pressure, a main pressure tank having a level controller to maintain a desired fine-particle fuel level therein while such fuel and a partial quantity of vehicle gas are delivered therefrom by a fuel-feed conduit for introduction into said reactor, a vehicle-feed conduit coupled to said fuel-feed conduit for introducing the major portion of vehicle gas to convey said fine-particle fuel into said reactor, and conduit means to feed a gasification agent into said reactor, the combination therewith of a control system to maintain a predetermined volumetric ratio between said fine-particle fuel and said gasification agent during feeding into said reactor, said control system comprising:

• first measuring means responsive to absorption of electromagnetic radiation by said fine-particle fuel in said fuel-feed line for producing a fuel-feed signal corresponding to the volumetric amount of fuel conducted by said fuel-feed line per unit of time,
• second measuring means responsive to the volumetric amount of vehicle gas conducted by said vehicle-feed conduit to produce a vehicle gas-feed signal,
• computing means responsive to said fuel-feed signal and said vehicle gas-feed signal to produce a control signal according to the following expression
• U.sub.1 . (U.sub.2 - U.sub.v)
• for all values of U.sub.2 greater than U.sub.v, where U.sub.1 corresponds to the reciprocal of said fuel-feed signal, U.sub.2 corresponds to said vehicle gas-feed signal, and U.sub.v is a predetermined comparison signal constant,
• first control valve means responsive to said control signal to vary the volumetric amount of vehicle gas introduced into said pressure tank for loosening and discharging fine-particle fuel into said fuel-feed conduit, and
• second control valve means responsive to said control signal to vary the volumetric amount of gasification agent fed by said conduit means into said reactor.