Distilled product quality
Thread Content
Three months after we stopped the plant operation, and not long after restarting the distillation process, the potassium permanganate test on the three columns showed a slightly red color in the samples taken from the reflux tank. What could be the reason for this?
The red color is likely rust; as the original poster mentioned, as long as the process parameters are well controlled, things should return to normal quite quickly.
The main issue is the presence of a large amount of reducing impurities, which are difficult to separate from methanol; therefore, it is essential to properly control the parameters of the pre-distillation column as well as the condensation temperature at the top of the column during distillation. As for why the color is slightly red, I think it’s due to the device having been idle for a long time and not being cleaned before being used again.
We expect the temperature at the top of the tower to be 3 degrees lower than usual. How can we raise this temperature? Is it because less extraction water was used?
Is it related to your steam that our prognosis is generally kept around 0.84?
What does around 0.84 mean?
If the temperature at the bottom of the tower is normal but the temperature at the top is low, it is likely that too much water has been added. As for the slight redness during sampling, it might be due to corrosion that occurred as a result of not emptying the reflux tank and the liquid level in the tower bottom after you stopped the machine
Oh, thank you. Do I need to take pictures before parking every time?
If the result of the potassium permanganate test is not satisfactory, it is related to proper control of parameters. The slightly red color observed in the samples taken from the reflux tank is due to rust inside the equipment... There is no need to drain the liquid level after shutting down the equipment; rust formation is likely caused by air getting inside or by incomplete cleaning of the equipment during its initial cleaning.