Limestone and the Sea: Lomar, Seabound Debut New Tech to Sequester Sea-Vessel CO2

by Jim Lane (Biofuels Digest) ... Lomar’s new subsidiary lomarlabs has signed a collab with Seabound, in a bid to reduce emissions and catalyze new, cost-effective methods to capture CO2 onboard vessels.

This project is part of the Clean Maritime Demonstration Competition Round 3, which was announced in September 2022, funded by the UK Department for Transport and delivered in partnership with Innovate UK. As part of the CMDC3, the Department allocated £60m to 19 flagship projects supported by 92 UK organizations to deliver real-world demonstration R&D projects in clean maritime solutions. Projects will take place in multiple locations around the UK from as far north as the Shetland Isles and as far south as Cornwall.

The technology gambit

Seabound has developed a patent-pending compact carbon capture device that can be retrofitted into a ship’s engine exhaust at the funnel. The CO2 chemically reacts with pebbles of quicklime, which then convert into limestone, keeping the CO2 locked in. The limestone pebbles are temporarily stored onboard before the ship returns to port, without any need for energy-intensive CO2 separation, compression, or liquefaction. The pebbles are safe, inert and non-toxic; abundantly available worldwide and reasonably priced. Once back in port, the limestone pebbles are offloaded and either sold in pure form or turned back into quicklime and CO2, for the quicklime to be reused onboard another vessel and the CO2 sold for utilization or sequestration.

Is it really carbon sequestration?

Well, yes and no. Think of it as a way to aggregate hard-to-sequester CO2. Originally, the quicklime was made by combusting limestone to make it, and releasing CO2 in the process. Taking the quicklime to the ship, sequestering CO2, bringing calcium carbonate pebbles back to land and then combusting those, doesn’t sequester CO2, precisely, at any given point there is either some net CO2 emission (after combustion) or it is CO2 neutral, while in stone form. There is good news in the aggregate, however, pardon the pun. That is, over time we have taken CO2 that would have been vented into the sky and turned it into an emission which is collected, controlled, used or stored. If we were to inject the CO2 in storage media, such as stable caves, over time there would be a net reduction in Co2. So, all good, if complex.