Regarding the issue of excessive ethanol levels
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In our pure methanol product, the ethanol content in the output from the pressure tower is very low, at around 5PPM, whereas the ethanol content in the output from the atmospheric pressure tower is as high as around 150PPM. How can the ethanol content in ethanol obtained from atmospheric pressure distillation be reduced to below 10PPM? We have a side extraction line on the first layer of packing in the atmospheric pressure tower; the methanol with a high ethanol content obtained from this extraction is sent to the recovery tower for further processing. Should the location of the side extraction line in the atmospheric pressure tower be moved upward? Moreover, the temperature of the atmospheric pressure tower can no longer be reduced, as it is necessary to ensure that the alcohol content in the bottom water does not exceed the specified limits. Let’s all analyze it.
What is the designed capacity of the recovery tower? If the ethanol content in crude methanol exceeds the designed value, it is difficult to resolve the ethanol issue in the atmospheric pressure column
In fact, there are already many posts on the forum regarding the quality of products from atmospheric pressure towers; you can search for them. There is more than just adjusting the extraction position as a way to make adjustments, and I think they can be made from the following aspects. . 1. Production locations: typically, atmospheric towers have several production locations. 2 Reflux ratio, tower pressure 3. Side-line production volume
Pay attention to temperature control at the point where ethanol is extracted from the side line. If the temperature at the extraction point is controlled too low, methanol is primarily obtained; if it is controlled too high, water is mainly produced, and ethanol tends to end up in the product. More layers of trays can be analyzed to determine the optimal extraction point.
The ethanol content in the product obtained from the atmospheric pressure column here is relatively low, while that in the product obtained from the pressurized column is higher than that from the atmospheric pressure column. Some sources state that ethanol is primarily removed in the atmospheric pressure column.
The ethanol content in the product obtained from the atmospheric pressure column here is relatively high, while that in the product obtained from the pressurized column is much lower than that from the atmospheric pressure column.