What to do when the principle of fail-open operation for the pneumatic emergency shut-off valve conflicts with that of the check valve?
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Emergency cut-off valve for the material at the bottom of the reflux tank: fails to function properly in case of a fault, resulting in closure. When there is a wind-related fault in the reflux valve that feeds liquid into the tower, FO opens. At this time, since the emergency shut-off valve is closed, there is no flow of reflux at the top of the tower – how can this be explained?
Emergency cut-off valve for material at the bottom; in case of failure, FC~~~ What kind of failure? Is it a major system failure or a valve actuator failure? ~~~Should the former have a FO?
Action in the event of a instrument air failure: when there is an instrument air failure, the return valve opens, while the emergency shut-off valve remains closed due to the failure
It is generally fail-safe; does the return valve FO serve to relieve pressure in the preceding system to ensure safety?
The discharge cut-off valve at the bottom of the tower can be used to maintain the level in the windward tank
The pressure storage can last for only a short time either. For emergency shutdown, is it better to use a pneumatic or an electric system?
When extraction is turned off and reflux is turned on, it’s as if there’s no extraction with full reflux – why is there no flow? No conflicts seem to be present either