Anmerkungen:
Nach Informationen von SSRN wurde die ursprüngliche Fassung des Dokuments August 28, 2022 erstellt
Beschreibung:
This work has been based on a conceptual design of a ship for transport of liquified CO2 from the port of Dunkirk in France to the Northern Lights CO2 terminal at Kollsnes in Norway. The ship is intended as a part of a possible logistics chain for the Carbon Capture and Storage (CCS) DMX Demonstration project in Dunkirk (3D). In total 1 Mt/y of CO2 will be captured and transported. Both for economic reasons acknowledging future taxation schemes for GHG emissions (ETS) and to be in line with the overall target of the CCS project, it is seen as an important task to reduce the GHG emissions from the ship. This should be looked upon from the full life cycle perspective of the ship, from production of materials, via the building process, the operational phase and finally the scrapping and possible recycling of the ship. However, this article focusses solely on what can be done to optimize the design of the ship with respect to GHG emissions during the operational phase. Ship building materials and production processes for these materials has therefore not been discussed in this paper. Nevertheless, it is an important point to take into consideration.In addition to the design of the ship, reduction of GHG emissions during operations has also been linked to operational measures such as low speed, weather routing, reduction of idle time waiting in harbour, use of electrical power from shore etc. Ship design that enables the operator to make use of such operational measures will be discussed but the operational aspects will only be included as a justification for the implemented design.There are two possible main sources for operational GHG emissions from a CO2 cargo ship:1. Emissions from the power sources for the ships propulsion and other ship systems such as heating, ballast pumps, cargo pumps.2. Fugitive emissions as loss from the cargo via pressure safety valves, cargo pumps, flanges, valves.Both of these sources for GHG emissions have been discussed in this paper.For item 1 the following has been studied, optimized hull design for the chosen cruising speed (hull form, energy saving devices), choice of engine solution (2 stroke, 4-stroke, diesel electric, fuel cells etc), selection of energy source (fossil, renewable or blend of these). Alternative energy such as waste heat recovery to save energy for CO2 capture, ship systems and accommodation functionsand use of renewable energy, such as windmills and solar power for the typical accommodation functions have been explored as well. Furthermore, sail power and means of reducing friction between the ship hull and the water have been studied.For item 2, the fugitive release from the cargo system has been estimated and due to the low CO2 impact compared to the propulsion and ship systems, this has not been treated further. It must be remarked that the potential fugitive emissions must be kept in mind when the cargo system is designed, optimizing insulation type and thickness, optimisation of the reliquefaction system with respect to efficiency and CO2 footprint and designing the cargo system with respect to minimized fugitive emissions.The possibility for capturing CO2 from the exhaust gas has been briefly visited. The largest contributor for GHG is the propulsion and the systems. From an earlier study the CO2 release from propulsion and power generation is approximately 800 kg/h compared to the estimated fugitive release from the cargo system at 0.75 kg/h.For our ship the following designs have been chosen to reduce the CO2 footprint:Slow speed, 10-12 ktOptimized hull for low speedOption to install air lubricationDual fuel low-speed 2 stroke engineFuel system is ammonia readyTwo flettner type rotor sails to reduce fuel consumptionKappel type of propeller with Controllable pitchDuring detail engineering, the technology choices shall be revisited for further optimization