A CSTR R01 is being used for a liquid phase reaction of reac

A CSTR (R-01) is being used for a liquid phase reaction of reactant A following first-order kinetics to convert to product B. The reaction is exothermic and is in the liquid phase. The feed (stream 1) comes from an upstream unit. The heat of reaction is removed by circulating some of the reactor contents with a pump P-01 through a heat exchanger with chilled water (E-01). For this reactor, indicate control schemes for the following: regulate the temperature of die reactor and regulate the liquid level in the reactor to keep it constant. Also explain how the control scheme would compensate for a change in flow late of the feed stream 1. Finally, what additional control measure would you implement to achieve a constant residence tune and hence constant conversion m the reactor?

Solution

a.temprature regulations

Temperature control includes advanced control electronics that monitor and control the process inside the reactor and also the internal processes of the system. When a control variable changes, the system is capable of readjusting the variable to the setpoint sans overshooting.

Accurate control electronics are needed to maintain the stability of a temperature control application. One option to assess control electronics is to look at the effort needed to set parameters. In a temperature control unit, users can enter a setpoint. Control electronics must be self-optimizing throughout the temperature control process to ensure optimum results.

B. regulate liquid level in reactor

To maintain the liquid level,the pressure differential sensor is used to calculate deltaP.There has to be valve to be fitted after the pump which will cause disturbance in inlet flow and there by changing pressure in the system.

c.compensating fluid flow rate

To control total feed flow,the orifice is used which runs on the principle of delta- P across this device.the disturbance is created due to change in pressure which will allow sensor to read and take action according to set limit of pressure and feed flow rate.

d. additional changes

Control Objective-Reactor space time
Controlled Variable -liquid level
Sensor Principle- pressure differential
Manipulated Variable-valve after pump
Disturbances that would
affect the controlled variable -pressure of pump