The liquid level at the bottom of the ethanolamine regeneration tower fluctuates frequently
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This post was last posted by I Ai Maomao Dye on 2017-8-3 23:22. The editor would like to ask you why the liquid level in the ethanolamine regeneration tower has been unstable? This is not the case for a short period of time, it has been like this since the start of construction. I looked at the liquid levels in the regeneration towers of other devices in our company and the same is true. The steam at the bottom of our tower is 1.0MPa steam produced by the reaction itself, and the temperatures at the bottom and top of the tower are also very stable. The ethanolamine entering and exiting the regeneration tower is self-pressured, and the flow rate and pressure are also very stable. It is considered that the entry position of the gas phase at the bottom of the tower is related. One stream of gas phase enters the bottom of the tower, and ethanolamine is forced into the reboiler, causing the page to drop. After the page of the reboiler rises, the gas phase becomes less, and the liquid level rises again, and so on. If this is the case, the reboiler may need to be replaced with a smaller one. Has this happened to anyone? Please enlighten me! I would like to ask if the gas return port of the reboiler of the ethanolamine regeneration tower that you have come across has any special structure to prevent the gas phase from impacting the liquid level? In our device, the air return port is bent downwards and reaches the liquid level at the bottom of the tower. Also, some devices I have seen have the air return port under the extraction port, and the extraction is to pump out the liquid in the liquid collecting tank.
Looking at Figure 2, it seems that when the hydraulic control valve position is fixed, the liquid level is also very stable. If this is the case, it should be related to the PID of the control valve.
That was when the liquid level at the bottom of the tower was full and the regulating valve was turned on.
This post was last edited by wkqkaken on 2017-8-1 23:03. By comparing the changes in water intermodal transport, cold amine closed-circuit circulation, hot amine closed-circuit circulation, and the current liquid level since the start of construction, it should be possible to determine whether it is a problem with the gas-liquid phase balance in the tower or the equipment itself. Furthermore, you can refer to the gas phase inlet position of the reboiler of the regeneration tower of other devices for further judgment.
If the heat exchange area of the equipment is too large, you can try to reduce the steam or the steam pressure to see if the reboiler is too large, the heat source is overheated, and the vaporization is too fast, causing the pressure difference between the tower kettle and the reboiler to be unstable and the liquid level to jump.
I once encountered a similar situation, and finally found that it was caused by the improper installation position of the liquid level gauge. The liquid level gauge is installed at a position where the gas-liquid inlet is offset, causing air to enter the liquid level gauge, resulting in inaccurate measurement.