EFFICIENCY OF THE USE OF SUPERCRITICAL EXTRACTION TECHNOLOGIE IN THE RECOVERY OF ETHYLENE OXIDE

Abstract

The article considers a model of supercritical СО2 ‒ extraction technology of ethylene oxide emission from its aqueous solution, which is proposed to replace energy consuming desorption process. The possibility of using normal alkanes as modifiers of the main extractant is considered. A comparative analysis of the energy consumption ofsupercritical and traditional technologies is carried out.

Methods. The Hysys program was used to model the processes.

Results.Was simmulated the extraction process of ethylene oxide separation from its aqueous solution using as an extractant pure and modified with propane, n-butane, n-pentane supercritical carbon dioxide supplemented with further purification and concentration of the desired product.The results indicate the inappropriateness of using n-butane and n-pentane as an additive to carbon dioxide. Comparison of three technological schemes (traditional and two extraction schemes with pure and modified carbon dioxide) shows that the energy consumption for heating the rectification columns is significantly lower in the case of SC-CO2 extraction technologies (115 MW ‒ traditional technology, 36 and 79 MW for SC ‒ CO2 extraction technology without additives and with the addition of propane, respectively), while the combined capacities of pumps and compressors were the least for traditional technology. But, since the degree of extraction of ethylene oxide in the extraction scheme with the addition of propane turned out to be practically equal to unity (0.996), the considered energy indices, referred to the kilogram of the product obtained, turned out to be the best for this scheme.