Regarding the adjustment of the fractionation tower?

1. What is the impact of the distillation column top pressure on product distribution? The top pressure of the distillation tower has almost no effect on the product distribution. The pressure at the top of the tower is high, requiring more energy for distillation ； A low tower top pressure requires less energy, resulting in energy savings. However: (1) The pressure operation of the distillation column must be stable in order to ensure even separation of the various components and to guarantee that the product meets quality standards. (2) The operating pressure of a column with light component distillation cannot be too low, as it will become difficult to control at such low pressures. 2. What are the methods for reducing the extraction at the top and bottom of the tower, increasing the production of middle distillates, and adjusting the first and second intermediate refluxes? And how does a fractionation tower adjust the top pressure? The backflow in No. 1 is increased, while the backflow in No. 2 is decreased. The top pressure of the fractionation tower is maintained at a reasonably stable level.