Issues regarding the modification of emergency shutdown operations
Thread Content
If an emergency stop is initiated, how should operations be carried out depending on the stop time?
My understanding of the current changes in parking is that the first thing the system’s parking conversion unit needs to do is 1)
1. On-site, fully open the shut-off valves of the cooling control valves in the conversion unit. 2. Fully close the steam control valve of the main control system. 3. Fully close the water temperature control valve of the main control system. 4. If the liquid level in the separation tank stops rising, fully close all the control valves as appropriate. 5. On-site, close at least one of the shut-off valves of those three control valves; if time permits, fully close the inlet valve of the conversion unit as well. 6. It is essential to regularly drain water from each quenching tank
Handle it according to different situations: 1. Short-term parking: 1) Pay attention to changes in the bed temperature to prevent the catalyst from overheating； 2) Shut off the level automatic control valves and backflow valves of each separation tank; set each automatic control valve in manual mode ； 3) Close the feed valve, steam valve, and cut-off valve of the waste boiler; pay attention to changes in the liquid level and pressure in the waste boiler ； 4) Pay attention to the pipelines from the high-pressure system to the low-pressure system; close the automatic control valves as well as the upstream and downstream isolation valves, and monitor the pressure changes in the low-pressure system ； 1. Long-term parking: 1) After effective isolation of the unit, depressurize it to a slightly positive pressure for operation (be careful to control the rate of depressurization); monitor changes in bed temperature to prevent the catalyst from overheating ； 2) Shut off the level automatic control valves and backflow valves of each separation tank; set each automatic control valve in manual mode ； 3) Close the feed valve, steam valve, and cut-off valve of the waste boiler; pay attention to changes in the liquid level and pressure in the waste boiler ； 4) Pay attention to the pipelines from the high-pressure system to the low-pressure system; close the automatic control valves as well as the upstream and downstream isolation valves, and monitor the pressure changes in the low-pressure system ；