What affects the purity of distillation products?
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What factors affect the purity of distillation products? This post was last edited by jh56565656 on 2007-12-20 21:14.]
1. Raw material purity 2. Treatment efficiency of light and heavy components removal 3. Reflux ratio
This is too broad – there are so many factors involved, such as the impurities in the raw materials and the efficiency of the separation equipment
So, which are the most common ones in the production process?
If we are talking about the control of the purity of distillate products, it is mainly related to reflux； While it generally refers to the purity of distillate products, covering a wide range ； There are many factors that influence it, which can be found in the relevant materials on the forum.
1. Fluctuations in raw material composition 2. The size of the flow rate into the tower: 3. Fluctuations in temperature and pressure inside the tower 3. When determining the reflux ratio, you should mainly consider the points mentioned above. By accumulating relevant data over time, once you see the real-time control records for that day, you will know what range the product purity falls within on that day. This is my work experience.
Number of plates, reflux ratio, recovery ratio, and outlet temperature
1. Top of tower temperature, which mainly affects the quality of the product at the top of the tower. 2. The bottom temperature primarily affects the quality of the product at the tower bottom. 3. The reflux ratio affects the quality of the product at the tower top. 4. The location of the feed inlet influences the product quality. 5. The number of plates affects the degree of separation; the more plates there are, the better the separation effect. 7. The properties of the filler affect the degree of separation. 8. With the equipment remaining constant, changes occur in the composition of the feed. It is necessary to adjust some corresponding process parameters.
1. Operational reasons: top temperature of the tower, pressure inside the tower, reflux ratio. 2. Raw material reasons: composition. 3. Hardware reasons: design parameters of the tower
This issue covers a wide range of aspects. I suggest you buy the book <<Questions and Answers on Methanol Production Operations>>, published by the Chemical Industry Press; it’s quite good
It’s not the case that the higher the number of plates, the better the separation performance… After all, an increase in the number of plates leads to a rise in pressure drop, and this increased pressure drop results in higher pressure and temperature at the bottom of the tower, which inevitably leads to increased energy consumption. To reduce the pressure and temperature at the bottom of the tower, and without being able to modify the equipment, the only option is to reduce the reflux rate, which can also lead to a decrease in the tower’s production capacity. Furthermore, an excessive number of trays results in the qualified product staying in the tower for too long; if it is a product with poor stability, decomposition may occur, which directly leads to a decline in product quality and yield.
The original poster’s question is too vague; it’s recommended to provide more specific details about your situation so that others can analyze it properly
The boiling points of the two media to be separated directly affect the height of the tower; the closer the boiling points of these two substances are to each other, the more difficult it is to separate them, and the greater the number of tray levels required.
For a fixed distillation unit, the influencing factors are as follows: 1. The nature and temperature of the feed. 2. Temperatures at the top and bottom of the tower. 3. Reflux ratio. 4. Pressure of the tower.