CO_2 QUALITY REQUIREMENT FOR A SYSTEM WITH CO_2 CAPTURE, TRANSPORT AND STORAGE

摘要

An important but not very well studied aspect in the analysis of a system with CO_2 capture-transport and storage is the quality requirements put on the captured CO_2, i.e. the concentration limits for the non-CO_2 components present in the stream sent to the storage site. This aspect could be seen as both an opportunity and a risk and could have a direct influence of the cost of CO_2 capture and storage:rn1. An opportunity to co-capture other main pollutants from power plant operations such as SO_x and store them together with the CO_2. Thereby, a concept with near zero emissions could be created and in addition costly and energy-demanding flue gas cleaning equipment could be excluded.rn2. A risk that components other than CO_2 in the captured stream could have a negative effect on the transport and storage system, both from a technical and environmental and health point of view, and therefore need to be removed. Stringent requirements are however likely to induce high costs for cleaning of CO_2.rnA discussion on CO_2 purity/specification is presented for the CO_2 capture transport and storage system. A list of potential impurities in the captured CO_2 stream is provided for considerations to bring forward a practical CO_2 specification which could be used as a guideline for CO_2 capture, transport and storage, and acceptable for environmental regulations.rnThe results from this initial investigation show that further investigations of the CO_2 specification especially from transport, storage and environmental points of view is needed in order to understand the impacts and limitations of various impurities on different procedures of CO_2 capture and storage.