Distillation column capacity expansion
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After the distillation column’s capacity is increased, the steam volume goes up while the pressure at the top of the column remains unchanged; why don’t the pressure difference across the column and the temperature in the reactor increase?
Could you provide more details about the specific situation?
What does capacity expansion mean? ? How to increase the capacity of a distillation tower? ? Has the tower diameter increased? Was it the filler that was replaced? ?
Since the diameter of the tower has been increased, it was considered whether there might not be enough steam, which could result in a too slow upward movement of the material vapor and thus leakage, leading to poor mass transfer. This is why the temperature inside the reactor fails to rise and the temperature at the top cannot drop.
Was the distributor of the corresponding tower modified as well?
When the diameter of the distillation column is increased, with the gas velocity in the empty column remaining unchanged, the theoretical vapor volume in the empty column will increase. If the gas-liquid ratio throughout the column becomes unbalanced, it will lead to changes in the pressure difference; if this pressure difference decreases, the temperature at the bottom of the column will surely drop. To a certain extent, incomplete removal of the light components from the tower bottom will lead to a decrease in the purity of the light components at the tower top. At this point, it is necessary to continue increasing the steam supply to the reboiler and to raise the reflux ratio appropriately, thereby increasing the gas-liquid load across the entire column. This will result in an increase in the pressure difference across the column, as well as a gradual rise in the temperature at the bottom of the column; only then will the purity of the light and heavy key components meet the required standards.