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551.
珠江三角洲地区大气污染最明显的特点就是臭氧浓度的升高导致大气氧化性增强,而挥发性有机化合物(VOCs)和氮氧化物是大气臭氧生成的重要前体物。珠三角地区工业体系发达,VOCs的生产及使用企业众多,由于VOCs的种类繁多,性质各异,排放条件多样,目前已经形成了一系列的VOCs废气实用治理技术。 相似文献
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文章通过综合分析、计算 ,提出用天然气代替煤作主要能源 ,走燃机热电联供道路 ,解决北京市大气环境恶化的问题 ,并对这一工程方案实施的可能性和优越性作了阐述 ,最后提出了多项实施建议。 相似文献
555.
将河南平顶山煤气公司原煤气输配系统改造成为自动恒压控制系统,从而提高安全系数,降低煤气输配电耗。 相似文献
556.
Benjamin K. Sovacool 《Environment, Development and Sustainability》2007,9(2):187-201
Contrary to claims from American politicians, lobbyists, and oil and gas executives, allowing energy development in the Alaskan
Arctic National Wildlife Refuge (ANWR) will harm the environment, compromise international law, erode the social significance
of wilderness protection, and ultimately fail to␣increase the energy security of the United States. After exploring a brief
history of the ANWR controversy, this piece argues that the operation of oil and gas refineries in ANWR will release discharged
solids, drilling waste, and dirty diesel fuel into the ecosystem’s food-chain, as they have from oil operations in Prudhoe
Bay. Less obvious but equally important, oil and gas exploration in ANWR will violate a number of international treaties on
biodiversity protection. In the end, development in ANWR will threaten the concept of wilderness protection, and will do little
to end US dependence on foreign sources of energy.
About the Author: Benjamin K. Sovacool is a doctoral candidate in the Department of Science and Technology Studies at the Virginia Polytechnic
Institute & State University in Blacksburg, Virginia. He works as a research analyst for the Consortium on Energy Restructuring
and is a Senior Research Fellow for the Virginia Center for Coal and Energy Research. He also just completed a Graduate Fellowship
in Energy Policy at the Oak Ridge National Laboratory in Oak Ridge, Tennessee.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
557.
As part of the Paris climate agreement, countries have submitted (Intended) Nationally Determined Contributions (NDCs), which includes greenhouse gas reduction proposals beyond 2020. In this paper, we apply the IMAGE integrated assessment model to estimate the annual abatement costs of achieving the NDC reduction targets, and the additional costs if countries would take targets in line with keeping global warming well below 2 °C and “pursue efforts” towards 1.5 °C. We have found that abatement costs are very sensitive to socio-economic assumptions: under Shared Socioeconomic Pathway 3 (SSP3) assumptions of slow economic growth, rapidly growing population, and high inequality, global abatement costs of achieving the unconditional NDCs are estimated at USD135 billion by 2030, which is more than twice the level as under the more sustainable socio-economic assumptions of SSP1. Furthermore, we project that the additional costs of full implementation of the conditional NDCs are substantial, ranging from 40 to 55 billion USD, depending on socio-economic assumptions. Of the ten major emitting economies, Brazil, Canada and the USA are projected to have the highest cots as share of GDP to implement the conditional NDCs, while the costs for Japan, China, Russia, and India are relatively low. Allowing for emission trading could decrease global costs substantially, by more than half for the unconditional NDCs and almost by half for the conditional NDCs. Finally, the required effort in terms of abatement costs of achieving 2030 emission levels consistent with 2 °C pathways would be at least three times higher than the costs of achieving the conditional NDCs – even though reductions need to be twice as much. For 1.5 °C, the costs would be 5–6 times as high. 相似文献
558.
Ammonium-dependent regulation of aerobic methane-consuming bacteria in landfill cover soil by leachate irrigation 总被引:1,自引:0,他引:1
The impacts of landfill leachate irrigation on methane oxidation activities and methane-consuming bacteria populations were studied by incubation of landfill cover soils with leachate and (NH4)2SO4 solution at different ammonium concentrations. The community structures and abundances of methane-oxidizing bacteria (MOB) and ammonia-oxidizing bacteria (AOB) were examined by PCRDGGE and real-time PCR. Compared with the pure (NH4)2SO4 solution, leachate addition was found to have a positive effect on methane oxidation activity. In terms of the irrigation amount, ammonium in leachate was responsible for the actual inhibition of leachate. The extent of inhibitory effect mainly depended on its ammonium concentration. The suppression of the predominant methaneconsuming bacteria, type I MOB, was responsible for the decreased methane oxidation activity by ammonium inhibition. Methaneconsuming bacteria responded diversely in abundance to ammonium. The abundance of type I MOB decreased by fivefold; type II MOB showed stimulation response of fivefold magnification upon the first addition but lessened to be lower than the original level after the second addition; the amount of AOB was stimulated to increase for 20-30 times gradually. Accumulated nitrate from nitrification strengthened the ammonium inhibition on type I and type II MOB, as a result, repetitive irrigation was unfavorable for methane oxidation. 相似文献
559.
This study was designed to clarify the influence of operating conditions on the formation and emissions of polychlorinated-pdibenzodioxins and dibenzofurans (PCDD/Fs) from a sintering process with hot flue gas recycling. A pilot scale sinter pot with simulated flue gas recycling was developed, and four key operational parameters, including temperature, oxygen content of the simulated waste flue gas, the coke rate of the sintering mixture, and the quicklime quality, were selected for exploring PCDD/Fs formation. The results showed that the temperature of the recycled flue gas had a major affect on PCDD/Fs formation, and a high temperature could significantly increase their formation during sintering. A clear linear correlation between the temperature of recycling flue gas and PCDD/Fs emission (r = 0.93) was found. PCDD/Fs could be reduced to a certain extent by decreasing the level of oxygen in the recycled flue gas, while sintering quality was unchanged. The coke rate had no significant influence on the formation of PCDD/Fs, but the quality of quicklime used in the sintering mixture could affect not only the amount of PCDD/Fs emissions but also the sintering productivity. Compared with a benchmark sinter pot test, PCDD/Fs emissions markedly decreased with improvements to quicklime quality. However, the reduction in PCDD/Fs emissions realized by using high-quality quicklime was limited by the temperature of the inlet gas. The highest reduction achieved was 51% compared with conventional quicklime when the temperature of the inlet gas was 150°C. 相似文献
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