Approximately 3% of all carbon emissions come from shipping
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A container ship with a total length of 240 meters. sounion trader recently completed testing its onboard carbon capture system while cruising around the Persian Gulf. The ship has space to hold tons of carbon dioxide, joining a small but growing number of ships seeking to reduce their impact on climate change by capturing and storing carbon dioxide emissions onboard. is difficult to find.
“We're miniaturizing systems that were designed for huge power plants,” he says. Louja Wen Seabound, a UK-based startup that is helping test run Sounion Trader.
Shipping accounts for approximately 3% of global CO2 emissions. To reduce it, shippers are using cleaner fuels, painting their hulls with foam to improve fuel efficiency, and even going back to sail. However, short-term options for achieving the industry's commitment to net-zero emissions by 2050 are limited.
Another possibility is to capture ship emissions. keep on board, but faces major obstacles. One is to provide energy to recharge the chemical adsorbents used to absorb CO2. tristan smith Researchers at University College London say some existing systems increase fuel use by a third just to capture half of the CO2 emissions.
The system, and the carbon it captures, also takes up space on the ship that would normally be used for valuable cargo. “Space is an issue,” he says. jasper ross At the Dutch research institute TNO. “Especially when you're talking about long voyages.” About three tonnes of CO2 is produced for every tonne of fuel burned. George Malupas At the Cyprus Marine and Maritime Institute. Once captured and stored, the added mass can affect the ship's stability and reduce fuel efficiency.
Wen said Seabound's small-scale tests captured about 1 tonne of CO2 per day. Although this is only a fraction of the ship's overall emissions, a full-scale system could capture as much as 95 percent of the ship's CO2, she says.
To save energy, Seabound moves some of its processes onshore. On ships, the exhaust air passes through a calcium oxide adsorbent and reacts with CO2 to form solid calcium carbonate pebbles. The company will then wait to refill the adsorbent until the pebbles are offloaded at the port for permanent storage. The tradeoff is space. Seabound's approach means the ship must carry tanks of sorbent with every ton of her CO2 captured. Still, Wen said the company aims to retrofit 1,000 ships for carbon capture by 2030.
Dutch company Value Maritime has taken a similar approach, using liquid amine adsorbents to capture carbon dioxide and refill it offshore. Yvette van der Sonmen Value Maritime says 26 ships are currently using its system in parallel with existing sulfur pollution scrubbers to capture up to 40 percent of CO2 in their exhaust, but the process is still being managed by third parties. Not certified by She said the company sells some of the captured CO2 to greenhouses to use as fertilizer for plants, but much of it remains in tanks at the port.
Such systems may now look attractive for reducing emissions, Smith says. However, the rapid scale-up of cleaner transportation fuels could quickly make them obsolete unless very high recovery rates can be achieved at sufficiently low costs. “The shipping industry currently has a very short window to decarbonize, because it has been very slow to start decarbonizing,” he says.
Source: www.newscientist.com
