Catalytic cracking distillation

This post was last edited by lijianhuai on 2011-10-9 at 20:04. When switching pumps, it is essential to first start the backup pump; once the backup pump is operating smoothly, then gradually remove the pump that is currently in use from the system. And follow the steps below strictly. Initial condition verification: For the pump in use – the inlet valve is fully open; the outlet valve is open; the bypass valve of the check valve is closed; the drain valve and vent valve are covered with plugs or caps; the outlet pressure of the pump is at a normal and stable level. For the standby pump – the inlet valve is fully open; the outlet valve is closed; the auxiliary systems are functioning properly; the pump has been preheated (for hot oil pumps); power has been supplied to the motor. 6.1.3.1 Starting the standby pump (without load): a. Start the electric pump [P] – Contact the operator responsible for that station to prepare for starting the pump [P] – Access the control panel of the standby pump [P] – Close the preheating valve of the standby pump [P] – Start the motor of the standby pump [P] – Stop starting the pump immediately if any of the following occur: abnormal leakage, abnormal vibration, unusual odors, abnormal noises, sparks, smoke, or persistently high current levels [P] – Verify that the outlet pressure of the pump has reached the required starting pressure and remains stable. 6.1.3.2 Switching over: [P] – Slowly open the outlet valve of the standby pump [P] – Gradually close the outlet valve of the pump that is currently in operation [P] – Verify that the outlet valve of the pump in operation is fully closed and that the outlet valve of the standby pump is opened to the appropriate position [P] – Stop the motor of the pump in operation (follow the procedures for stopping centrifugal pumps) [P] – Close the outlet valve of the pump that was previously in operation [P] – Verify that the pressure of the standby pump and the motor current are within normal ranges [P] – Adjust the flow rate of the pump [I] – Set the control valve for the minimum flow rate of the pump to automatic mode

Is it useful to reduce the amount of slurry discharged before shutting down the pump, so as to keep the slurry circulation rate stable? Expert guidance

3rd floor, it doesn’t work; a smooth transition will do. The type of pump is important; for example, the water removed before pumping crude gasoline or top-loop pumps ； The heat pump is in normal condition.

Crude gasoline, water removed before starting the top circulation pump.

It is impossible to avoid fluctuations during pump switching; what was said above are just general statements. It is best to achieve a smooth transition when switching pumps, as brief fluctuations have little impact on production