Ethanol content control

Most of them are caused by the leakage of methanol water cooler, which leads to poor methanol separation effect and serious alcohol content in the synthesis gas. Such problems mainly cause the increase of dimethyl ether, aldehydes, and ethanol lipids.

Ethanol is a heavy component, and the product is unqualified. This is caused by the high temperature of the pressurized tower and the heavy components moving up. The amount of steam at the bottom of the tower can be reduced, or the reflux ratio can be increased.

If the ethanol content in the crude alcohol is high, how can it be effectively removed during the distillation process? The current problem is that the ethanol in the atmospheric tower can be controlled through the side line, but the effect of adjusting the reflux volume and heat load in the pressurized tower is not obvious. The ethanol content still reaches about 80PPm at a reflux ratio of 3.0. Looking forward to seeing you all!

1. I agree with liujianguo1116's opinion. Find the reason in the synthesis and look at the alcohol content of the circulating gas. If it is high, it will promote the reaction to develop toward higher alcohols. Also look at the synthesis system pressure, airspeed, and catalyst temperature. 2. Support the idea of ​​extending the road and reducing the extraction of pressurized towers. 3. Some articles suggest adding water to the pre-distillation tower to reduce the concentration of crude methanol, and diluting and concentrating the ethanol in the crude methanol with water to control the upward movement of ethanol into refined methanol during the distillation process. 4. It also depends on the composition of the raw gas. The ethanol content of crude methanol produced from different raw gases is different. If the ethanol content of the crude methanol is very high, it will be difficult to control the product indicators to double A standards in the distillation section. My personal opinion, please give me some advice.

1. There are no abnormal changes in the process conditions and analytical indicators of the synthesis system. It can basically be ruled out that the ethanol content is high due to the operation of the synthesis system. As for whether the ethanol content increases in the later stages of catalyst use, resulting in an increase in the difficulty of distillation and separation, it remains to be verified by analytical results. We are currently preparing to analyze the ethanol content in crude alcohol. Since we do not have the ethanol content data in the early stages of catalyst use, if anyone has data on the ethanol content in crude alcohol at different stages of using the NC307 catalyst, please let us know. I would be very grateful! 2. The current measures are to reduce the heat load of the pressurized tower and increase the reflux ratio to prevent the ethanol from moving upward. However, this results in the atmospheric tower being overloaded and the tower body temperature being low. For a long time, the residual alcohol content will exceed the standard. 3. I have also seen the idea of ​​increasing the amount of extraction water, but I think it doesn’t matter much. If the previous measures cannot solve the problem, I am ready to give it a try. Thank you for your attention, and continue to look forward to seeing you!

1. Check the ethanol content in the crude methanol to see if it exceeds the normal value. 2. Add more extraction water to the pre-column. 3. Add appropriate reflux to the pressurized tower.

The ethanol content in crude alcohol is also a reason. Some are hundreds of PPM and some are 2000PPM.

The ethanol content in crude alcohol is difficult to separate. Let me tell you an empirical method to see if it is useful. If it is not effective, do not use it. Use side line extraction. The temperature at the side line extraction point should be controlled at about 95 degrees.