Sequestering, carbon dioxide

Goff, F. and Lackner, K.S., Carbon dioxide sequestering using ultramafic rocks, Environ. Geosci., 5(3), 89,1998. 

Estimated cumulative amounts of carbon dioxide sequestered from supply chain for automobiles powered by hydrogen current hydrogen production technologies, 2010-2050, 78... 

Ehlig-Economides C. and Economides M.J. Sequestering carbon dioxide in a closed underground volume. 2010 Journal of Petroleum Science and Engineering 70(1-2) 123-130. 

There is also interest in finding feasible and harmless ways to capture and permanently sequester carbon dioxide underground or in the oceans, thereby preventing its accumulation in the atmosphere.2 Carbon dioxide concentration in the... 

Discusses how to sequester carbon dioxide when producing hydrogen from fossil fuels... 

Compared to conventional combustion, carbon dioxide exits a coal gasifier in a concentrated stream instead of a diluted flue gas. This allows the carbon dioxide to be captured more easily and used for commercial purposes or sequestered. 

Almost a billion metric tons of C02 are sequestered in 2025. Then, hydrogen is produced from coal, oil and gas fields, with the carbon dioxide extracted and sequestered cheaply at the source. Large-scale renewable sources and nuclear energy are producing hydrogen by electrolysis come 2030. 

A second reason for the slow substitution of biomass for fossil fuels is an economic one. The economic issues of hydrogen production are dealt with in Chapter 15. Hydrogen produced from fossil fuel under conditions in which carbon dioxide is sequestered is compared with the economics of hydrogen produced from biomass. 

The idea here is to capture carbon dioxide from power plants and then inject it into natural gas hydrate reservoirs assumed to contain primarily methane hydrate. Thus one achieves the simultaneous sequestration of carbon dioxide with the production of natural gas. Lee et al. (2003) presented laboratory data that showed the replacement of methane molecules by C02. Yoon et al. (2004) and Ota et al. (2005) confirmed these laboratory findings. Park et al. (2006a) used a CO2/N2 mixture containing 20 mol % carbon dioxide (flue gas) instead of pure C02 and noticed that the methane recoveiy increased from 64 to 85 %. A similar idea for sequestering captured C02 is to use it as cushion gas for natural gas storage in reservoirs (Oldenburg, 2003). 

Carbon dioxide mainly enters the oceans from the atmosphere. It dissolves in the cold surface waters around the north and south poles. When these cold waters sink, they carry the carbon deep into the oceans where it can be stored for hundreds of years. Because of their ability to store carbon, the oceans are known as a carbon sink. The sea as a carbon sink has become increasingly important in recent decades because human activity is adding increasing amounts of carbon dioxide to the atmosphere, and much of it ends up in the sea. According to the National Aeronautics and Space Administration (NASA), almost half of the carbon added to the atmosphere hy fossil fuel burning ends up sequestered in the ocean. 

Emissions of carbon dioxide are comparable with emissions from a conventional coal plant. However, should future environmental regulations require the removal of CO2, an IGCC plant can separate and sequester CO2 from the process at a significantly lower cost than conventional technologies. 

The use of fossil fuels to meet variable electrical demands may be limited in the future because of concerns about the price of natural gas and climate change. With any deep reduction in greenhouse gas emissions, carbon dioxide emissions will likely be limited to transportation, consumer products and other mobile applications - not stationary applications such as peak power production. While carbon dioxide from fossil power plants may be sequestered underground, such fossil power plants are likely to be uneconomic for the production of intermediate and peak electricity because of their high capital costs (MIT, 2007) and the difficulties in operating such plants with variable output. 

Fuel boxes can be distributed like soft drinks to multiple distribution channels, even dispensing machines. Consumers can get their fuel anywhere and any time. By 2025, one-quarter of the industrialized vehicle fleet uses fuel cells, which also account for half of new sales. Renewables start out slowly but pick up speed after 2025. Some one billion metric tons of co2 are sequestered in 2025, and, after 2025, hydrogen is widely produced from coal, oil and gas fields, with carbon dioxide extracted and sequestered cheaply at the source. Also, large-scale renewable and nuclear energy schemes to produce hydrogen by electrolysis become attractive by 2030. ... 

Whether or not the carbon dioxide (C02) by-product is sequestered when hydrogen is produced from fossil fuel. 

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