Japanese firms INPEX and Sumitomo Osaka Cement have started pilot testing a reusable CO2 capture process called calcium looping at a facility near Tokyo. The method turns captured CO2 into calcium carbonate, which can be shipped at normal pressure and temperature, then processed to release the CO2 for underground storage. The companies plan to install the system on large vessels first, targeting tightening international shipping emission rules. The key detail is the loop: calcium hydroxide captures CO2, becomes calcium carbonate, then is regenerated back to calcium hydroxide after the CO2 is stripped for storage. If the sorbent can survive many cycles without losing performance, this could offer a lower-energy alternative to conventional amine-based capture for marine use. The project also lines up with INPEX's CCS storage plans and Sumitomo Osaka Cement's push into carbon mineralization. No cost or capture efficiency figures were released in the announcement, so the main open questions are energy input, sorbent durability, and whether the whole chain, including transport, actually cuts emissions compared to current options.
