Cooling compressor interstage coolers

The gas stream leaves a first-stage compressor in an olefin plant at a pressure of 48 psia and a temperature of The gas flow rate is 295,000 Ib/h consisting of 240 Ib-mol/h of water vapor and 10,000 Ib-mol/h of hydrocarbon. The exit gas must be cooled to 97°E Water to cool this gas steam is available at 90°F for use in a direct-contact gas cooler. The heated water effluent from this column should be at a temperature of about 130°F so that it can be returned to the center of the water quench tower. What will be the size of a packed interstage cooler, and how much can it reduce the gas-side pressure drop of 4.0 psi through the present tube-and-shell heat exchangers ... 

For multistage compressor, it is better to provide an interstage cooler to cool down the gas before It enters the next stage. This will reduce the gas volvtme to be compressed and horsepower comsumptiott. 

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