Please ask everyone**, how is the mixed refrigerant recovered during LNG plant shutdowns for maintenance?
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Please ask everyone**, how is the mixed refrigerant recovered during LNG plant shutdowns for maintenance? We are conducting an LNG shutdown for maintenance today; this reduces the system load while also decreasing the opening degree of the throttles for the pre-cooling refrigerant and the liquefaction refrigerant. My understanding is that the reason for doing this is to reduce the opening of the throttle valve in order to decrease the amount of liquefied refrigerant that vaporizes, which in turn increases the liquid level in the refrigerant separator, allowing the refrigerant to be recovered. But there are no pipelines on the PID diagram for recovering the liquid phases from the pre-cooling refrigerant separator and the liquefying refrigerant separator... **How do they proceed with recovering the refrigerant? We are currently studying* in another place; usually we watch others carry out the operations. The workers here only know how to perform the tasks but don’t understand the principles behind them, so we have to ask ** for help
For short-term shutdowns, we do not recover the liquid phase; before shutting down, the liquid phase should be turned off first. The liquid refrigerant remains in the outlet buffer tank, and the compressor itself is depressurized. In the case of long-term shutdowns, the liquid phase needs to be recovered in advance, and it is sent to the refrigerant recovery tank via the outlet separator for recovery
May I ask, what about the gas phase? How to handle it
May I ask, what about the gas phase? How to handle it
May I ask, what about the gas phase? How to handle it
How is the liquid phase actually recovered? Is it just to recover the liquid phase from the outlet separator?
The gas phase can also be recovered; if your company has containers with sufficient pressure resistance, it can be transferred there, and then replenished after the process starts again
It is not possible to recover the gas in the vapor phase; the only option is to close the inlet and outlet of the compressor and release pressure in the unit back to the operating pressure
There is no liquid level at the inlet or between stages; only the outlet has a liquid level. The subcooled refrigerant can be recovered and remaining in the system. If it is necessary to inspect the refrigerant lines, they must be emptied first
There is no liquid level at the inlet or between stages; only the outlet has a liquid level. The subcooled refrigerant can be recovered and remaining in the system. If it is necessary to inspect the refrigerant lines, they must be emptied first
Well, thank you**. We didn’t recover any light components this time either, but during the shutdown the supervisor said we should recover as many heavy components as possible, which means we need to increase the liquid level in the outlet separator as much as possible? How can the liquid level in the outlet separator be increased as much as possible?