Abstract
Cryogenic air separation plants producing pressurized gaseous oxygen (PGOX) near 40 bara at purities 99.8% and 95% and gaseous nitrogen at 5 bara above 99.99% purity are analyzed. Oxygen is compressed either by external compression process (EC) or by internal compression (IC). IC is gasification of pumped liquid oxygen in the main heat exchanger (MHX). IC plants require appropriate combinations of pressure and flow of air and size of the MHX to vaporize PGOX with reasonable specific power consumption (SPC). Based on exergy and economic analyses of the ASU after simulating the plant in Aspen HYSYS®™8.6, the values of parameters which give high exergy efficiency with low capital and operating expenditures are determined. SPC of IC is 7–8% higher than that of EC. Addition of crude argon column improves the purity of oxygen from 96.3% to 99.8%. Recovery of oxygen improves by 5% with 3–4% reduction of SPC for both types of plants. Capital requirement for both EC and IC plants is about 50% higher with argon separation than without it. HP air between 33% and 31% of total air flow at 70 bara and 80 bara respectively is the most preferred range of operation of IC plants for 95% purity of oxygen. The corresponding flow of HP air is 5% lower for 99.8% purity of oxygen.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
