Recent tests at Dutch research institute TNO have shown the technical feasibility of capturing CO2 directly from exhaust gases. In a new research project, DERISCO2, ship-based carbon capture will be prepared for piloting. The target ship is Heerema’s Sleipnir, a heavy lift vessel.
Zero emission shipping options rely on the use of electricity or alternative fuels, such as blue hydrogen or ammonia. However, that requires major modifications to the ships and the logistics of fuel distribution. Ship-based carbon capture (SBCC) could be a transition solution, which can be implemented on short term.
In previous studies, SBCC has been shown to be technically feasible. Large ships (above 3000 kW) running on LNG have been identified as most promising use cases for SBCC, operating with solvents that capture CO2 and release it at relatively elevated pressures (above 6 bar).
Speeding up Implementation
In a parallel project, CO2ASTS, SBCC units are being designed to be retrofitted for three different ships, with maximum heat integration so to reach economic feasibility. In DERISCO2, implementation is to be accelerated by closing knowledge gaps for SBCC; namely finding the optimal solvent system and assessing the effect of ship motions on the capture efficiency. This work will lead to a cost effective solution for onboard CO2 capture and thereby reducing time before implementation.
Reactive Absorption
The SBCC process is based on using reactive absorption to capture up to ninety per cent of the CO2. The efficiency is high, especially for LNG powered vessels such as the chosen use case, the Sleipnir. The engine provides the rest heat for the capturing process and the cold of the LNG can be used for liquifying the captured CO2. The stored CO2 as a liquid, can easily be offloaded while harbouring.
DERISCO2 Goals
DERISCO2 is to:
- demonstrate the feasibility of capturing CO2 from the exhaust gas of an LNG-fuelled marine propulsion engine, using an advanced solvent tailored for the SBCC application;
- demonstrate the feasibility of desorbing CO2 at high pressures (up to 10 bar), eliminating the need of a compression unit. This will greatly lower the cost of SBCC;
- demonstrate the use of a membrane contactor (MC) column, instead of a packed column, for CO2 absorption. This will reduce the size and weight of the capture system;
- evaluate the effect of ship motions to the SBCC system. For that, first a kind of absorption tests under ship motions will be performed;
- perform a techno-economic evaluation of SBCC onboard of Heerema’s Sleipnir, a heavy lift vessel.
The ultimate goal of DERISCO2 is to prepare the technology for onboard piloting on board the Sleipnir in the near future.
Partners in the DERISCO2 project are TNO in Delft, Conoship International BV in Groningen, FME in Zoetermeer, Heerema Marine Contractors in Leiden, and Linde Gas Benelux in Schiedam. The project has recently started and the first results are expected halfway through 2020. DERISCO2 has received a 167,710-euro grant from the Dutch Topsector Energy programme.
The DERISCO2 project will be discussed in detail in SWZ|Maritime’s January 2020 issue.
