PROCESS RETROFITTING VIA INTEGRATION: METHODOLOGY AND APPLICATIONS

Abstract

In this doctoral research, a heuristic-based methodology for retrofitting with focus on process integration is developed in this thesis. It consists of four steps: (1) Base case analysis, retrofit target and contributing units; (2) Generation of an improved solution without capital investment; (3) Generation of integrated solution(s); and (4) Comparison of retrofit solutions and selection. The methodology is applied to retrofit a conventional isopropanol (IPA) process; two retrofit designs are developed. One reduces the manufacturing cost by 12%, and the other reduces the manufacturing cost by 23%. The former retrofit scheme is further retrofitted to a process with two RDs, which has manufacturing cost similar to that of the latter. Finally, process retrofitting via hybridization is discussed. An amine absorption process for removal of CO2 and H2S retrofitted by adding membrane units to sweeten a new feedstock with increased CO2 content.