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Is it possible to recover heat from the discharge of reciprocating compressor pushing hydrogen from 20 bar to 120 bar? Is there any safety concerns if we use it to preheat DM water for further processing as BFW?
Conditions are like this:
3 stage reciprocating compressor,
Hydrogen flow : 3.5 tph,
Discharge temperature: approximately 130 deg C in each stage,
1stage suction pressure: 20 bar, suction temp: 30 deg C
2nd stage suction pressure: 40 bar, suction temp: 30 deg C
3rd stage suction pressure: 70 bar, suction temp: 30 deg C
 
Answers
27/05/2012 A: Prakash Pimparkar, Environmental Consulting Services , prakash.pimparkar@yahoo.in
Keiths reply answers all.With low Cp of Hydrogen it may not be economical to recover the heat even though technically possible.You can calculate the recoverable heat by simple calculation as a product of Hydrogen flow x Cp x ( t in -t out) for hydrogen.
Get the cost of waste heat boiler (HE) and compare the annual returns to check the feasibility. It doesn't cost much to do the calculations.
24/05/2012 A: keith bowers, B and B Consulting, kebowers47@gmail.com
Possible? Yes. Economical? very unlikely.
Easy to calculate the possible energy savings. Cost of the piping and exchangers are likely to exceed the discounted cost savings. Don't forget to increase delta P on the compressor which increases Hp requirements