Heat Exchanger Sizing

The problem:

I need to cool natural gas from 130 deg F to 110 deg F using a shell & tube heat exchanger with 70 deg F water.

Question: How much water do I need?

Design conditions:
Ambient Temp: 100 deg. F .
Altitude: 6700 ft, atmospheric pressure 11.6 psia Process Gas: Natural gas, sweet, 95 % methane, 2% CO2, specific gravity 0.55-0.60, 46 ,000,000 scf/day ( 90,000 lb/hr) , 130 deg F, operating 350 -545 psi, Relief valve set at 500 psig . Cooling Medium: Produced water,80-90 psig, 70 deg F, specific gravity 1.04.

I am piping/pipeline facilities engineer (not a process engineer).

I have requested information from a heat exchanger vendor. The flow rate of water required per vendor calculation is very high. I have ran hand calculations and compared my answer with the online calculation available at http://www.freecalc.com/hxfram.htm. The vendor reported flow rate is 3 times higher than what I came up with (hand calc & freecalc).

Supported formulas with your reply are very much appreciated.

Cheers, Received on Sun Sep 11 11:23:00 2005