Studying the effect of solvent properties in treatment design within CO2 Integration Networks

Abstract

Carbon Dioxide Integration mainly targets the recovery of CO2 streams, and assesses the allocation of those recovered streams into CO2-using sinks, with an overall aim of attaining a minimum cost of a CO2 network that could meet a prescribed emission target. Meeting emission targets often introduces numerous challenges, especially when energy intensive processes are involved. Hence, CO2 Integration aims to identify appropriate CO2 capture, allocation, and utilization options. There exists numerous processes (or CO2-using sinks) that convert CO2 streams into value added products, while generating revenue in some cases. However, many CO2 sink options may be costly, especially if a high purity CO2 stream is required in the process. Thus, the incorporation of treatment units is imperative, to separate CO2 gas from the remaining gaseous emission material, which is in fact the most expensive design step in CO2 integration systems. This study focuses on assessing the effect of varying the temperature of the solvent to be used in the treatment stage of CO2 on the overall performance of the entire integration network attained. A MINLP formulation has been established based on key design parameters whilst taking into consideration important technical performance constraints that effectively describe the system to be assessed. A more detailed cost model for the treatment units was developed, to establish the effect of varying the emission reduction targets onto the overall performance of CO2 integration systems.