Summarize the process design method and optimization measures of distillation column

Distillation technology is a common technology widely used in petrochemical, chemical industry, precision chemicals and other industrial fields, and the basic process has a separation device process. Starting from the source of the process, in order to improve the distillation technology, improve the efficiency of the separation process, reduce energy consumption, and achieve energy saving and emission reduction, the process design of the distillation column must be realized first.
       The separation requirements depend on the entire process route, and the process parameters calculate the column reflux ratio, feed position, column temperature, column bottom temperature, feed composition, production line recovery position, number of trays (plate column) or packing height. Then computational fluid dynamics calculates parameters such as plate spacing, pressure drop, column height, column diameter to select column interior fittings such as tray type or packing type. After strength calculation and inspection, the tower wall thickness and material will be selected, and the control plan will be determined.
       Most of the rectification towers used in industry are complex in material world, so the use of sideline mining is actually calculated by the method. Fluid mechanics calculations often use software calculations, and most of the components in the tower are stereotypes or components. After completing the internal design, we will select the tower according to pressure, temperature, medium environment, etc., and calculate parameters such as wall thickness, load, etc. Propose processing requirements and draw equipment diagrams.
       According to the process requirements, draw a process flow diagram PID with auxiliary instruments, valve selection, control scheme determination and pinch point control. Optimizing a distillation column begins with identifying individual design variables and adjustable design variables in a number of parameters.
       The pressure optimization of the existing single tower is relatively simple. In the summer when the temperature of the tower Condenser can be met, the heat load of the reboiler can be reduced by using a relatively low working pressure on the premise that tap water can be used for cooling. In practical designs, equipment costs due to increased wall thickness increase to increased pressure, so compliance with separation requirements is relatively beneficial for low voltages.
       In theory, the more trays in the distillation column, the better the separation effect and the higher the manufacturing cost. The same separation requirements and number of plates, small or condenser, reflux is less than the heat load of the reboiler; with the same number of plates and reflux ratio, the separation purity of the column top and column bottom products is higher; the same separation requirements and reflux costs, the required trays Less in quantity.