【Registration Power】Seeking advice on this question regarding the boiler’s blowdown rate – where is the mistake in my solution?
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This post was last edited by longkui1990 on 2017-7-12 at 22:45. The question and the reference answers are as follows. Here is my solution; could you please tell me where I went wrong? I would appreciate some guidance from those who know more. O(∩_∩)O Thank you
1) Based on the diagram you drew, your boiler feed water composition is 0.6D + Dpw + 0.4D, which is greater than 1D. Therefore, the formula used to calculate the blowdown rate should not be Dpw/D, but rather Dpw/(0.6D + Dpw + 0.4D). 2) Additionally, there is an issue with the alkalinity of your feed water as well. The alkalinity of soft water at 1.5 includes 0.01 from 40% of the recycled water; thus, the actual alkalinity of the feed water entering the system should be greater than 1.5. It can be understood in this way: although the hardness of the feed water is high, the concentration is diluted by the condensate water, and the alkalinity at the outlet of the water treatment equipment being 1.5 does not mean that the alkalinity of the feed water entering the system is also 1.5.
I’ll think about it again tonight. Thanks, mate
Keep it up, keep working hard; I hope it goes well this year