What are the advantages and disadvantages of adding a distillation section to a distillation tower, and how is it operated?
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What are the advantages and disadvantages of adding a distillation section to a distillation tower, and how is it operated?
It should be explained upstairs: how does adding a distillation section to a distillation column achieve this? Is it by moving the feed inlet position, reducing the stripping section while increasing the distillation section, or by simply increasing the number of trays?
It is likely that the purity of the product at the top of the tower is insufficient. The disadvantage of adding more tower sections is that it requires significant modifications to the equipment, results in high costs, and increases the pressure drop across the plates. In such cases, the first option to consider is the use of more efficient trays or packing; additionally, internal heat removal can be considered, but this would require recalculating the operating parameters of the tower.
My company once had two sets of distillation towers modified, with the work carried out by the manufacturer itself. One set was imported and the other was domestically produced; yet neither set met the requirements for modification – in fact, their performance was even worse than that of the original design. Moreover, the modification process was extensive and complicated, resulting in high costs. It was all a lot of effort for nothing in the end. To carry out renovations, I believe a new, precise design is necessary; many of these renovations are the result of the leaders’ arbitrary decisions, as no real experts were consulted for advice or design work. The quality of such renovations is poor, and the leaders’ goal is merely to boost their own achievements. Such things are common in many companies.
Advantage: Increasing the distillation section can improve product purity； Reduce the return flow rate under certain load conditions to save steam ； Disadvantage: The negative pressure tower requires attention to pressure drop ； Increase in fixed costs ；
Adding a distillation section is a relatively complex task. First, the new section needs to be fabricated; then, using a crane – one with sufficient lifting capacity, which depends on the height of the tower; I estimate a capacity of 300 tons is required – the tower’s head, reflux pipes, and product extraction pipes must be cut off. The specific method involves welding a basket, with a person inside that basket! To save time, it’s possible to pre-weld the reflux pipes and product removal pipes for adding distillation stages – simply connect them directly! Also, once the work is completed, insulation and leak testing must be carried out! Apart from an increase in tower pressure, there are no changes in operation!