Chain problems of the Texaco gasifier
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Please discuss what interlocks should be set for the trip out due to low liquid level in the Texaco gasifier Should a low-flow trip interlock be installed for the quench water? Should a low-liquid-level trip interlock be installed in the water wash tower?
Oxygen flow: 3 options to choose from; slurry flow: 3 options to choose from; syngas outlet temperature in the cryogenic chamber: 3 options to choose from; burner cooling water: 3 options to choose from. It is not necessary to set the flow rate of cryogenic water, nor is it necessary to set the liquid level in the scrubber tower
Forgot about this haha, choose two out of three for the ultra-cold chamber level
Texaco’s shutdown interlocks: 1. Instrument air pressure; 2. Level of water in the wash tower feed tank; 3. Temperature of the process gas at the exit of the gasifier; 4. Burner cooling water system; 5. Level of liquid in the evaporator; 6. Oxygen timeout (to protect the furnace bricks); 7. Liquid oxygen pump; 8. Shutdown of the boiler system; 9. Oxygen flow rate; 10. Shutdown of the coal slurry pump; 11. Coal slurry flow rate (usually two or three flow meters are used for interlocking purposes); 12. Pressure difference across the burner; 13. Pressure difference in the gasifier; 14. Level of liquid in the quench chamber (usually also two sensors are used); 15. Shutdown button. Generally, no shutdown interlocks are installed for low levels in the wash tower or low flow rates of quench water
There is also testing of the CH4 content after washing, the CO content in the burner cooling water, and the CO content in the superheated steam on the shell side; these are also used for safety interlocks
Interlock shutdown is triggered when the flow rate of the quench water is extremely low; a 10-second delay should be set for activating this shutdown interlock. If the liquid level in the scrubber tower is low, an interlock may not be necessary.
There is a high-high trip setting for the oxygen-to-coal ratio; what are everyone’s interlock values? We 520
Our company does not have a interlock for low cold water flow; instead, there is an interlock for high temperature of the outlet process gas
In our plant, when the liquid level in the waste boiler dropped, the gasification furnace stopped operating. Previously, the interlock system caused the gas flow to be directed to the gasification torch; but when the valve opened suddenly, the high volume of gas combined with the existing gas flow caused the pipelines connected to the torch to collapse. The entire plant was shut down for a month, as some of the pipelines and wires were damaged, which resulted in a water supply outage throughout the plant for several days. It’s really unfortunate