What are the stable factors in distillation tower operation?

Everyone knows that distillation towers are pressure vessel equipment, so what are the stable factors in their operation?

The main factors for stable operation of distillation towers are as follows:

1. The impact and constraints of material balance;

In the operation of the distillation tower, it is necessary to maintain the stability of the products at the top and bottom of the tower, and maintaining the material balance of the distillation device is a necessary condition for the steady-state operation of the distillation tower. The material balance of the distillation tower is usually controlled by the liquid level at the bottom of the tower.

2. The impact of tower top reflux;

The reflux ratio is the main factor affecting the separation efficiency of distillation towers, and it is often used in production to regulate and control the quality of products.

There are several methods to adjust the reflux ratio.

(1) Reduce the extraction amount at the top of the tower to increase the reflux ratio.

(2) When the overhead condenser is a condenser, the amount of overhead refrigerant can be increased to increase the condensate volume and increase the reflux ratio.

(3) For forced reflux in the middle storage tank with reflux liquid, the reflux flow rate can be temporarily increased to improve the reflux ratio, but the reflux storage tank must not be emptied.

3. The impact of feed heat conditions;

When the feeding condition changes, the feeding position should be appropriately changed and the reflux ratio should be adjusted in a timely manner. Generally, there are several feeding positions in the distillation tower to adapt to the feeding conditions during production and ensure feeding at the appropriate positions in the distillation tower. If the feeding condition changes while the feeding position remains unchanged, it will inevitably cause changes in the composition of the distillate and the residual liquid in the reactor.

4. The influence of tower kettle temperature;

The kettle temperature is determined by the kettle pressure and material composition. During the distillation process, only by maintaining the specified kettle temperature can product quality be ensured. Therefore, kettle temperature is one of the important control indicators in distillation operations.

When raising the temperature, both product quality and process losses should be considered. In general, it is customary to use temperature to improve product quality and reduce process losses.

5. The impact of operational pressure;

The pressure of the tower is one of the main control indicators of the distillation tower. In distillation operations, the adjustment range of operating pressure is often specified. Excessive fluctuations in tower pressure can disrupt the gas-liquid balance and material balance of the entire tower, resulting in products not meeting the required quality.