Fresh feed is combined with a recycle stream and fed to a reactor to form CH3OH. The reactor effluent is fed to a separator that removes effectively all of the methanol as a pure stream. The remaining products are recycled, but part of this stream is purged. A diagram is shown below:
The synthesis gas has a small amount of methane present as a contaminant. which does not participate in the reaction. The single pass conversion of CO in the reactor is 18%. Finally, the purge stream is used to eliminate both methane and excess hydrogen, and is set to have a methane fraction of 3.2 mol%. For simplicity, assume a 100 mole/hour total Fresh Feed rate.
(Hint: Answer the following questions in whatever order seems simplest to you Also, this problem gets a lot simpler if you think of the excess hydrogen in the feed as an inert.)
(a) What is the composition of the purge stream?
(b) What is the molar production rate of methanol product?