How much impact can the stability of distillation operations have on daily production? ?
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Our plant uses three-column distillation. Yesterday, both the volume of coke oven gas and the synthesis reactions were stable, but the steam supply for distillation was not consistent; the temperature at the bottom of the pressure column remained around 131 degrees, and the output volume was about 10 cubic meters. The temperature in the middle section of the atmospheric pressure tower is 79 degrees, with a reflux volume of 16 cubic meters. The operator kept saying that the steam volume was unstable, and adjustments had to be made frequently. By the time work ended, it was found that the production volume was five tons less than it had been under the same amount of coke oven gas the previous day! How much of an impact can distillation operations have on production? If the synthesis reaction proceeds well and a large amount of crude alcohol is produced, then wouldn’t the yield be quite promising once converted to terms of concentration? Please give some advice.....:handshake
What is your factory’s production capacity? Comparability is only possible if the distillation feed over the two days is the same.
An unstable steam supply leads to longer distillation times and a decrease in production, which is normal; it has little to do with the efficiency of the methanol synthesis reaction
Unstable steam has a significant impact on distillation; it can be said that in normal operating conditions, distillation relies entirely on steam! Unstable steam is likely to increase the loss of methanol through the venting of non-condensable gases from the pre-tower and in the wastewater from the atmospheric pressure tower, resulting in a lower yield of methanol. However, a lower production volume in one of the columns does not mean that the methanol produced in smaller amounts is lost; steam fluctuations can cause changes in the liquid levels in the columns and in the amount of liquid on the trays, and the methanol that is not produced may simply be temporarily present inside the column
If the steam is unstable, the daily production can vary by around 10 tons. With unstable steam, the heat balance cannot be maintained stably; as a result, the efficiency of distillation is not optimal and production decreases. To achieve high yields in the chemical industry, it’s not about increasing the load to the maximum, but rather about ensuring stable operation over the long term.
First, determine whether the amount of methanol entering the pre-tower is the same as yesterday’s level (it’s not the case that it will be the same just because the coke oven gas is the same); if it’s roughly the same, then analyze the methanol loss in the overhead vapor from the pre-tower and in the wastewater from the atmospheric pressure tower. If the losses here do not increase significantly, then the 5 tons of methanol that were produced less have simply accumulated within the system and have not escaped.
If the feed rate remains constant, the alcohol content in the wastewater is not high, and the vent volume from the pre-tower is low, then one should check the pressure in the tower; it should be elevated. In other words, unstable steam supply causes other parameters to fail to meet the required standards, and the steam consumption is likely to be quite high.
Distillation is really important! The components of the synthetic crude methanol also have an impact! Lack of steam definitely has an impact! If everything is sent back, the amount recovered will naturally be less!
The analysis above is all correct; one thing that needs special attention is that doing this for an extended period of time can lead to flooding in the distillation tower, with serious consequences.