A parametric study of spectral radiation of gas-fuel combustion media in 1-D furnace cases for energy utilization

Oxy-fuel combustion is one of promising technologies for CO2 capture, which uses simple flue gas processing normally including compression, dehydration and purification/liquefaction (non-condensable gas separation). However relatively high levels of impurities in the flu gas present more challenges for the gas processing procedure. This paper studied the sensitivity of operating parameters to inlet composition, the effects of impurities on energy consumption, and the relationship between energy consumption and operating parameters. Results show that comparatively the total compression work is more sensitive to the composition of SO2 if the total mass flow is constant; while the operating temperature of purification is more sensitive to N2. To pursue the minimum energy consumption, from the viewpoint of impurity, the content of O2, N2, Ar and H2O should be lowered as much as possible, which means the amount of air leakage into the system and excess oxygen should be controlled at a low level in the combustion; as to SO2, if it is possible to co-deposit with CO2, its existence may be helpful to decrease compression work. From the viewpoint of operating parameters, low intermediate pressure, high intercooling temperature and high outlet pressure are favorable to achieve high energy utilization, if heat recovery is considered.

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Atmospheric observations of CO2, 14CO2 and O2 concentrations to capture fossil fuel CO2 emissions from the Greater Tokyo Area

10.5194/egusphere-egu2020-12366 ◽

2020 ◽

Author(s):

Yukio Terao ◽

Yasunori Tohjima ◽

Shigeyuki Ishidoya ◽

Mai Ouchi ◽

Yumi Osonoi ◽

...

Keyword(s):

Continuous Monitoring ◽

Significant Contribution ◽

Fossil Fuel ◽

Flux Measurement ◽

Fuel Combustion ◽

Fossil Fuel Combustion ◽

Atmospheric Observations ◽

Late Evening ◽

Gas Fuel ◽

Oxidation Ratio

The Grater Tokyo Area is the most populated (38 million) metropolitan area in the world. To capture fossil fuel carbon dioxide (CO2) emissions from the Grater Tokyo Area, we performed ground-based atmospheric observations for measuring concentrations of CO2, radiocarbon in CO2&#160;(14CO2), oxygen (O2) and carbon monoxide (CO) at Tokyo Skytree (TST, with high altitude (250m) inlet) and Yoyogi (YYG, turbulentCO2&#160;flux measurement site located in resident area) in Tokyo and at National Institute for Environmental Studies (NIES, suburb/rural area) in Ibaraki, Japan. The 14CO2&#160;measurement was used for separating the fossil fuel CO2&#160;emissions from the biotic emissions. Results from 14CO2&#160;measurements showed that a ratio of fossil fuel-derived CO2&#160;to the variation of CO2&#160;concentrations was 71% in average for winter both at TST and YYG but varied from 44% to 92%, indicating significant contribution of biotic CO2&#160;in Tokyo. The O2:CO2&#160;exchange ratio (oxidation ratio, OR) was used for the partitioning of CO2&#160;into emissions from gas fuels and gasoline. We observed larger OR in winter than in summer (due to both wintertime increases of fossil fuel combustion and summertime terrestrial biospheric activities) at TST and YYG and larger OR in the morning and late evening in winter due to increase of gas fuel combustion at YYG. We showed that the O2&#160;concentrations might be also used as a proxy for continuous monitoring of fossil fuel CO2&#160;content by assuming typical ratio of gas fuels and gasoline combustions. The presenter will introduce the related projects including development of building/road-scale dynamic CO2&#160;mapping and grid-based CO2&#160;emission inventory with high special resolution in Tokyo.

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Beyond Malthus

Low Carbon Energy Transitions ◽

10.1093/oso/9780199362554.003.0005 ◽

2018 ◽

Author(s):

Kathleen Araújo

Keyword(s):

Carbon Emissions ◽

Energy Supply ◽

Energy Use ◽

Innovation Policy ◽

Heat Budget ◽

Ghg Emissions ◽

Primary Energy ◽

Fuel Combustion ◽

Energy Utilization ◽

Primary Energy Supply

This chapter explores the evolving understanding of carbon and sustainability since the 18th and 19th centuries. Relevant applications of influential ideas are then identified with respect to knowledge, innovation, policy, and meta-level change. More than 100 years ago, Swedish scientist Svante Arrhenius hypothesized about the onset of ice ages and interglacial periods by considering high latitude temperature shifts (NASA Earth Observatory, n.d.). Applying an energy budget model and ideas of other scientists, like John Tyndall, Arrhenius argued that changes in trace atmospheric constituents, particularly carbon dioxide, could significantly alter the Earth’s heat budget (Arrhenius, 1896, 1897; NASA Earth Observatory, n.d.). Today, science indicates that the global, average surface temperature has continued to rise alongside the increase in greenhouse gases. Among global GHGs, CO2 emissions have increased by more than a factor of 1,000 in absolute terms since 1800. During that time, global carbon emissions found in the primary energy supply increased by roughly 6% per year (Grubler, 2008a). This growth in carbon emissions from energy is significant because CO2 from fuel combustion dominates global GHG emissions (IEA, 2015a and 2015b; IPCC, 2013). As noted earlier, 68% of the global GHGs that are attributed to human activity are linked to the energy sector; namely, fuel combustion and fugitive emissions (IEA, 2015a). Within this share, 90% consisted of CO2 (IEA, 2015a). In contrast to the rise in absolute numbers, carbon emissions per unit of output in the global primary energy supply has decreased 36% overall or by slightly less than 0.2% per year over the past two centuries (Grubler, 2008a). This subtle decarbonizing pattern in the energy mix is explained by the faster growth rate of energy use in relation to the rate of carbon emissions from that use. The delinking of energy utilization and carbon emissions occurred in part with the introduction of less carbon-intensive fossil fuel sources, like natural gas, in which a higher hydrogen-to-carbon ratio is evident (Gibbons and Gwin, 2009; Grubler, 2004, citing Marchetti, 1985).

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