Carbon Capture and Storage (CCS) has seen growing momentum as a crucial strategy for meeting CO2 emission reduction targets. However, it comes with different technical and strategical challenges. One of the major challenges associated with CCS is the multi-actor value chain, which based on individual actor requirements, may not be necessarily aligned with each other and therefore requires coordination and agreement.
An important design consideration is the quality of the CO2 stream as it moves through the CCS process. Various industries still consider CO2 as a waste stream and as such it only has limited quality control based on local regulations. This paper will discuss the various issues associated with CO2 quality in the various elements of the CCS chain, from collection, through transportation to storage.
There are various technologies providing discrete solutions for different elements of the CCS chain. However, for a cost-effective CCS design, a holistic approach should be applied.
At custody transfer points within a CCS chain, CO2 will need to meet specification criteria for type and quantity of allowable impurities. Impurities may be inherent in the captured CO2 or carried over from processes or reaction by-products. Some impurities may have significant impact on the behaviour of CO2 rich fluid even in small ppm quantities and adversely affect the CCS chain integrity or operation. CO2 not meeting specification criteria risks non-acceptance at custody transfer points. This paper shall address the critical considerations for CO2 quality at each of the CCS chain interface points.
This paper will provide a high-level overview of how impurities can significantly affect the calculation of CO2 rich fluid properties and behaviour, chemical reactions, corrosion risk, etc. Additionally, some of the gaps in the current understanding and standards will be addressed and their possible economic impact on CCS chain design and operation.
The novel part of this work is holistically looking at the whole CCUS chain and addressing how CO2 quality and specification can affect each part of the chain and their impact on the economics and viability of the solution.