The Ship Carbon Recycling Working Group (WG) of Japan's Carbon Capture & Reuse Study Group has pronounced that the carbon recycled methane produced by methanation technology can be recognised as a ‘zero emission ship fuel’.
A technical paper describing the details of the calculation procedure and evaluation conducted by the WG has been published in the latest issue (Vol. 56, No. 4) of the official journal of the Japan Institute of Marine Engineering.
In a statement issued today (19 July) to mark the WG’s position, Japanese shipowner Mitsui O.S.K. Lines (MOL) said that carbon recycling, which is the process of capturing and reusing emitted CO2, is ‘becoming increasingly important as one of the pathways to realise a carbon-neutral society’.
MOL said that the WG – which started exploring the feasibility of using methanation technology for zero-emission ship fuels in July 2020 – has ‘assumed and evaluated the following four processes as the supply chain for carbon-recycled methane fuel: (1) CO2 separation and capture, (2) CO2 transportation, (3) methanation fuel synthesis, and (4) methanation fuel liquefaction.’
MOL continued: ‘As a result, the CO2 emission per unit calorific value of carbon-recycled methane fuel by methanation was calculated as approximately 27-gCO2/MJ (regarded as Well to Propeller).
‘This figure is comparable to other alternative fuel candidates generally recognized as zero-emission fuels, confirming that carbon-recycled methane can be recognized as zero emission ship fuel. In addition, further reduction to approximately 20-gCO2/MJ is expected by improving the efficiency of the separation and capture technology, and using electricity produced from renewable energy.’
MOL added that, in order to further demonstrate carbon recycled methane’s suitability as a ship fuel, the WG will continue to work on issues such as: CO2 transportation by large-scale liquified CO2 carrier vessels; the supply of hydrogen from renewable energy; the prevention of methane slip; and the supply infrastructure of liquefied methanation fuel.