Problems with carrying desulfurizer in dry gas
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It often happens at night that the dry gas of this device (FCC) carries desulfurizer. The liquid level in the tank suddenly rises at night, and returns to normal after several liquid cuts. However, the desulfurization of dry gas and liquefied gas in other devices did not occur. I have been thinking about it for a long time and have no clue. Please enlighten me. This post was last edited by wfme816 on 2009-3-30 09:33 ]
Foam the desulfurizer and try to increase the operating pressure.
If it is the same set of amine liquid systems, the following aspects can be considered:: 1. Does the flow rate of FCC dry gas exceed the design load? 2. Does the FCC dry gas itself contain liquid? 3. After eliminating the above reasons, you can consider washing and steaming the FCC dry gas desulfurization tower once. Excessive accumulation on the tray is sometimes a factor that causes amines.
I have also encountered the same problem, and it happened in the past few days. Sometimes I don't wear it for a month, but I always have it for a few days. I don't know why!
Agree with what the third floor said. After ruling out other causes, you can consider that there is too much packing or tray accumulation. The main consideration is the salt problem, which can be solved well by washing with water.
Are there changes in dry gas load or system pressure? Pour liquid?
Is the operation at night different from that during the day? Such as pressure and boundary position?
Generally speaking, it is due to the desulfurizer foaming. It may be that the desulfurizer supplier did not add a good defoaming agent. Check the desulfurizer used carefully. Because defoaming agents are generally added during the production process of desulfurizers, but if you do not indicate this during the bidding process for defoaming agents, some suppliers will not add them or add less. Increasing the operating pressure will only help temporarily, and entrainment will soon begin again.
The temperature is low at night, the temperature of the diesel in the reabsorption tower is low, and the oil in the dry gas causes the desulfurizer to foam. It is recommended to adjust the water cooler operation in time at night. I suggest the owner skim the oil. If there is no effect, you need to clean the tower.
Inject defoaming agent to inhibit the foaming of desulfurizer
It will be effective if you add it, but you can’t add it often.
There are several reasons why amine liquid foams. First, the concentration is too high and the viscosity increases. The solution is to use rare amine liquid.； The second is that the absorbed gas contains too many heavy components. The solution is to enhance the absorption of heavy components by the front gas. ； Third, the degradation products in the amine liquid increase. The solution is to strengthen the renewal of the amine liquid. Another option is to increase the temperature of the amine liquid at night to prevent the temperature from being too low and increasing the viscosity of the amine liquid.
It may be caused by the temperature difference. You should control the dry gas temperature to be 3-5 degrees lower than the amine liquid temperature to prevent the amine liquid from foaming.
Generally, the temperature should be low at night, and the temperature after dry air cooling is low, resulting in pressure fluctuations and liquid entrainment. If this phenomenon occurs, write down the operating parameters at that time for reference.