Heat Exchange using cooling water
Heat Exchange using cooling water
(OP)
Hi All,
I've got a process stream at 390 deg C and wants to cool up to 38 deg C using cooling water at 29 deg C. I understand to limit the pipe wall temperature at a high process inlet temp. I have to cool/temper the process sream with air up to a certain temp and then intoduce into the H-E using cooling water.
Can somebody guide me as how to estimate the process inlet temperature which would not result in a high tube wall temperature.
Thanks in advance,
I've got a process stream at 390 deg C and wants to cool up to 38 deg C using cooling water at 29 deg C. I understand to limit the pipe wall temperature at a high process inlet temp. I have to cool/temper the process sream with air up to a certain temp and then intoduce into the H-E using cooling water.
Can somebody guide me as how to estimate the process inlet temperature which would not result in a high tube wall temperature.
Thanks in advance,
Asif Raza





RE: Heat Exchange using cooling water
RE: Heat Exchange using cooling water
IMO you will need a train of exchangers in series to create good countercurrent, otherwise you will never get down to 38 deg.
Other than that, there is room for improvement in the sense that you would be extremely energy-inefficient by doing nothing useful with the 390 deg stream except heating up cooling water (or cooling air) to an unpractically high temperature. Isn't there any other 250-300 deg stream that can be used for initial cooling, then a ~150 deg stream, then finally cooling water or air to reach the target of 38 deg?
RE: Heat Exchange using cooling water
Is asifraza0's intention to limit temperatures to avoid hard water scale formation ?
RE: Heat Exchange using cooling water
I'm planning to cool the process up to 200 deg C using air (blowing air in a double pipe H-E) and then use cooling warter to further cool it to 38 deg C.
Asif Raza
RE: Heat Exchange using cooling water
Normally an air-fin array would be used, with a fan below each cell, and the process side outlet temperature might be around 60 C. Then cooling water can be used to finish the job. I wouldn't put 200 C process fluid against cooling water, because of the possibility of excessive fouling and film boiling.
RE: Heat Exchange using cooling water
Also if you can give brief description of your process streams, so that some other option may be considered.
Azhar Chaudhary
Asstt Operations Manager
Bosicor Pakistan Ltd
E-add: azharchaudhary.tec@bosicor.com.pk
Cell: +92-300-2943166