The company has been sending to the sewer the filtrate from one of our chemical processes. This filtrate contains 63 vol. % methanol. The recovery of this methanol would reduce the amount of purchased methanol. The recovery would also reduce the Biological Oxygen Demand of the plant effluent. In the near future the local sewer authority will be billing the company for BOD. The goal of the recovery process is to obtain methanol of satisfactory quality for reuse in the process from which it came. A literature search and a laboratory study verified the non-ideality of the system. Preliminary calculations indicating the separability of the system were verified by batch still demonstrations. A recovery process was developed to utilize a set of existing equipment. This process was successfully demonstrated. The column runs with the calculated set of parameters yielding 99.5 vol. % pure methanol with an overall recovery of 99% by volume. The economic analysis indicates savings of $24,800/year in purchase of methanol and an additional saving of $34,000/year in BOD charges. The total operating expenses will be about $8,000/year. This gives an overall savings of about $50,000/year. Therefore it is recomŽmended that this process be put into use.
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