Specify Control Scheme: Heat Exchanger

7.22. A reactor is cooled by circulating liquid through a heat exchanger that produces low-pressure (10 psig) steam. This steam is then split between a compressor and a turbine. The portion that goes through the turbine drives the compressor. The portion that goes through the compressor is used by 50 psig steam users. 100 p steam can also be used in the turbine to provide power required beyond that available in the 10 psig steam. Sketch a control concept diagram that includes all valve actions and the following control strategies: (a) Reactor temperature is controlled by changing the setpoint of the turbine speed controller. (b) Turbine speed is controlled by two split-range valves, o... click for more

Specify Control Scheme: Vapor-Phase Reactor

8.14. Overhead vapor from a distillation column passes through a partial condenser. The uncondensed portion is fed into a vapor-phase reactor. The condensed portion is used for reflux in the distillation column. The vapor fed to the reactor can also come from a vaporizer which is fed from a surge tank. To conserve energy, it is desirable to feed the reactor with vapor directly from the column instead of from the vaporizer. The only time that the vaporizer should be used is when there is not enough vapor produced by the column. Sketch a control concept diagram showing: (a) Total vapor flow rate to the reactor is flow controlled by valve V-i. (b) Reflux drum pressure is controlled by valve... click for more