IEAGHG organised the fourth Post Combustion Capture Conference (PCCC4) in Birmingham, Alabama, supported by NCCC. The event attracted 110 attendees from 16 countries and included two visits to full-scale Carbon Capture facilities, the NCCC and Kemper sites.

PCCC-4 opened with a visit to the NCCC facilities, where we were lucky to see the membrane-based post-combustion capture technology based on the new PI-2 material (presented recently in the 2017 NETL CO2Capture Review meeting, see http://ieaghg.org/docs/General_Docs/Information_Papers/2017-IP51.pdf), chemical absorption system (now testing systems developed in collaboration with University of Texas at Austin (UTA)) and pre-combustion process.

The three days of PCCC4 presentations opened with plenary sessions, which included talks on the NCCC and Kemper demonstration projects, CCS in China and USA, followed by updates from the technologies tested by UTA. Moreover, a different policies perspective, given by Clear Path, completed the overview of the global CCS status.

Approximately 45 technical presentations included international research on 2nd - 3rd generation capture systems, novel solvents, modelling, industrial emissions, environmental impacts, pilot and large scale projects. On Tuesday, I was lucky to chair two fascinating sessions on last advances on amine solvents and industrial emissions. Firstly, we had the opportunity to see the last progresses on two research lines on hybrid amine solvents. We saw previous updates in TCCS-9 (see http://ieaghg.org/publications/blog/119-meetings-and-conferences/796-tccs-9) and GHGT-13: first, containing organic compounds and, secondly, including imidazoles, explained by UTA and NTNU respectively. In that case, recent kinetic results contributed to the further evaluation of those systems. Two presentations, given by Trimeric Corporation and UTA, showed the NO2 removal with Aqueous Sulfite process at two scales, including pilot testing at NCCC. Updates on cyclic oxidation piperazine and its avoidance were also given by Paul Nielsen, from UTA. Apart from amine solutions, biphasic solvents are lately emerging due to several advantages they might offer, as reduction of stripper size. We saw different approaches, based on liquid-liquid solvents (Ilinois State Geological Survey), based on precipitating systems (Lund University) and using catalysts. Still, the debate on high viscosity of the rich phase must be considered and research on the impact of that on the techno-economic analysis is still ongoing.

Through the industrial emissions session, we saw a good mixture of technologies. Following the presentation in GHGT-13 (http://www.sciencedirect.com/science/article/pii/S1876610217319598), ETH Zurich continued their research on the chilled-ammonia process in the context of the CEMCAP project (see http://ieaghg.org/docs/General_Docs/Publications/Information_Papers/2017-IP33.pdf), where we observed great interest from the audience. The results from the Tomakomai demonstration project in Japan were engaging, where we heard about social perception and government acceptance. As highlight, the discussion on the difference between the storage capacity and injection limitation due to regulations gave an additional realistic point of view. It is interesting to highlight the talk given by Hajime Kimura, from Mizuho Information & Research Institute, showing the work on the creation of guidelines on environmental risks of CCS systems in Japan. Also UK representatives offered some contributions for the next steps on risks guidance.

The session on 2nd-3rd generation systems included new configurations for membrane systems, as the two-layer structure with nanoparticles presented by Shinshu University. Through scaling-up, demonstration projects presented in this event included the technologies tested at NCCC, TCM, PICA Plant, University of Kentucky and Niederaussem.

PCCC4 closed with the visit to the Kemper site, based in Mississippi. We had the opportunity to see the pre-combustion facilities, including the fluidised bed gasifier and the ash separator column. Moreover, Richar Exposito explained rock formation possibilities we can find in storage sites and different strategies on CO2 injection campaigns.

In conclusion, PCCC4 covered a wide range of emerging systems at advanced stage of development. Full-scale projects proved that CCS technologies are technically feasible but still some concerns on price, regulations and environment must be addressed. Next generation of post-combustion capture technologies can include any of the systems exhibited during this event and IEAGHG will continue looking at those closely.