The impact of excessive heat exchanger area requirements
Thread Content
When designing a heat exchanger, a certain amount of energy is generally left. For example, a reboiler with an amount of 30 to 50% (column temperature 100 degrees Celsius). Assuming that the actual operating heat transfer coefficient meets the design expectations, under a certain heat load, due to the excessive area, the heat transfer temperature difference will be reduced, such as the heat medium of the reboiler. It is 0.6MPa saturated steam. Due to the reduction in heat transfer temperature difference, the steam condensate will inevitably leave the heat exchanger in a subcooled state. If the condensate is required to be recycled to generate low-pressure steam (such as 0.3MPa), the supercooled condensate will most likely not be recovered, and it will also easily cause water hammer after being merged into the recovery pipe network. I would like to ask everyone if there is any truth to this.
It makes sense. The margin we leave is generally very small, maybe 20%, or even no margin. It is the customer who has the final say...
Generally calculated using HTFS, then X1.1 without phase change, and X1.2 with phase change
The analysis is reasonable, but in practice it will cause unstable tower operation and even drain the tower reactor.