The effect of automatic deliquification and automatic control of the liquid separation tank between compressor stages!
Thread Content
The liquid separation tanks between all stages of the three compressors in my unit are all equipped with automatic liquid drainage, and are equipped with high and low liquid level interlocking shutdowns. However, due to instrument reasons and control valves, all of them have been changed to on-site manual dehydration. In the past, instrument display errors caused the machine to interlock and shut down many times, and internal leakage in the control valve caused the liquid level to be too low, causing interlocking and shutting down multiple times. It is a bit troublesome to switch to on-site manual deliquidation. I don’t know if anyone has a good idea! Can the low level interlock be canceled? We all took off the interlock a little higher on site, and then closed the on-site stop valve. The originally advanced equipment became like this! Thanks
The interstage liquid separation tank can be set with high and low limit alarms, but interlock shutdown seems to be rare.
If the pump is sending liquid to the outside, the high and low liquid levels of the instrument can be connected to the pump to start the pump when the liquid level is high and stop the pump when the liquid level is low. If it is self-pressurizing, it can be connected to the control valve. There is also a certain alarm, and there is no need to set up an interlock shutdown. The instrument should be replaced with something that is easy to use. A magnetic flop level gauge is more useful for alarms.
Think about it, if deliquification is frequent, it is better to use the original regulating valve control. Regarding the chain, the chain shutdown with high liquid level should be retained to prevent the compressor from being damaged by liquid. Low liquid level may cause low inter-stage pressure and high-pressure medium from the deliquidizing line to flow into the low-pressure equipment. We do not have chain shutdown with low liquid level. It is recommended that you switch to fully closing the hydraulic control valve. ； You can consider the causes of instrument failures in the past and replace them with reliable ones. Instrument failures are more frequent in the initial stage, but they will get better in the future. The best way is to consider increasing reliability, such as changing the liquid level to a transmitter and a liquid level switch, two out of two or two out of three, adding a chain automatic shut-off valve to the main pipe of the deliquidating valve, etc. Try to use instruments to increase operating workload and prevent human errors.
The valve can be opened when the liquid level is high, and the valve can be closed when the liquid level is low.
Why set a low liquid level alarm?