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碳交易为煤层气利用提供了一条重要的市场化融资渠道。目前国际、国内碳市场均只有1个方法学适用于煤层气利用项目。我国共注册了84个煤层气利用CDM项目,年减排量3 577万t(CO_2当量),已有40个项目获得了3 767万t(CO_2当量)减排量的签发,山西占最大比例。宁夏有4座煤层气发电站开展了碳交易工作,其中3个CDM项目实现了134.1万t(CO_2当量)交易。建议依托国际、国内碳市场,从加强政府引导、整体规划布局、探索规划类碳交易等4个方面促进宁夏煤层气的利用。 相似文献
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Yasin Şöhret Olcay Kıncay T. Hikmet Karakoç 《International Journal of Green Energy》2018,15(3):145-150
Emitted exhaust gases from aircraft are an issue of concern from an environmental perspective. Many research studies have been conducted aiming to reduce aircraft emissions in the hope of preventing any further increase in climate change and global warming. Within this scope, the present study intends to present a methodology for an optimum gas turbine engine selection with regard to emitted exhaust gases. The methodology focuses on five different turbofan engines which constitute the power unit of a commonly used passenger aircraft. At the end of the study, it is considered to be impossible to achieve a minimum exhaust emission for each gas. For this reason, it is considered to be better to optimize the engine with the aim of reducing nitrogen oxide emissions or other exhaust emissions. 相似文献
536.
Yang Wang Wenjie Du Lianliang Chen Haoran Wang Ziyang Shan Zhengyang Zhou Wenwei Li 《环境科学学报(英文版)》2023,35(2):745-757
Air pollution is a major obstacle to future sustainability, and traffic pollution has become a large drag on the sustainable developments of future metropolises. Here, combined with the large volume of real-time monitoring data, we propose a deep learning model, iDeepAir, to predict surface-level PM2.5 concentration in Shanghai megacity and link with MEIC emission inventory creatively to decipher urban traffic impacts on air quality. Our model exhibits high-fidelity in reproducing pollutant concentrations and reduces the MAE from 25.355 µg/m3 to 12.283 µg/m3 compared with other models. And identifies the ranking of major factors, local meteorological conditions have become a nonnegligible factor. Layer-wise relevance propagation (LRP) is used here to enhance the interpretability of the model and we visualize and analyze the reasons for the different correlation between traffic density and PM2.5 concentration in various regions of Shanghai. Meanwhile, As the strict and effective industrial emission reduction measurements implementing in China, the contribution of urban traffic to PM2.5 formation calculated by combining MEIC emission inventory and LRP is gradually increasing from 18.03% in 2011 to 24.37% in 2017 in Shanghai, and the impact of traffic emissions would be ever-prominent in 2030 according to our prediction. We also infer that the promotion of vehicular electrification would achieve further alleviation of PM2.5 about 8.45% by 2030 gradually. These insights are of great significance to provide the decision-making basis for accurate and high-efficient traffic management and urban pollution control, and eventually benefit people's lives and high-quality sustainable developments of cities. 相似文献
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The Great East Japan Earthquake in March 2011 devastated the eastern region of Japan.Due to the resulting nuclear accident,Japanese Cabinet decided to revise its energy policies.The Energy and Environment Council in National Policy Unit published options on the nation’s scenarios for energy and economy in 2030.We estimated the economic impacts of the options to national economy and households in 2030.Finally,we clarified significant factors to establish a secure,affluent and low-carbon society based on the energy scenarios. 相似文献
538.
It is well established that wet deposition of sulphate in the UKhas fallen by a much smaller fraction than have emissions of sulphur dioxide. Dry deposition of sulphur has decreased in proportion to the decline in emissions. A number of suggestionshave been made which offer possible explanations for this non-linearity between emissions and wet deposition. In this paper amodel of the processing of sulphur dioxide by aqueous phase cloudchemistry in a cloudy boundary layer is presented. This work doesnot simulate all the details of the mechanisms by which sulphate is incorporated into precipitation. It does, however, explorethe non-linearity of this oxidation process. It is shown that theoxidation of sulphur dioxide, in these conditions, over the UK isdominated by oxidation by ozone. The rate of sulphate productionis then controlled by the availability of the one basic trace gasin the atmosphere ammonia. Using realistic concentrations of thereacting species this is found to simulate well the observed non-linearity. The model predicts that sulphate and sulphur dioxideconcentrations will be uncorrelated in the cloudy boundary layerbut that ammonium and sulphate will be well correlated. Fieldobservations at a cloudy site in Northern England are consistentwith these predictions. 相似文献
539.
Methane emissions from 3 different landfills inthe Netherlands were estimated using a mobileTuneable Diode Laser system (TDL). The methaneconcentration in the cross section of the plumeis measured downwind of the source on a transectperpendicular to the wind direction. A gaussianplume model was used to simulate theconcentration levels at the transect. Theemission from the source is calculated from themeasured and modelled concentration levels.Calibration of the plume dispersion model isdone using a tracer (N2O) that is releasedfrom the landfill and measured simultaneouslywith the TDL system. The emission estimates forthe different locations ranged from 3.6 to 16 m3 ha-1 hr-1 for the differentsites. The emission levels were compared toemission estimates based on the landfill gasproduction models. This comparison suggestsoxidation rates that are up to 50% in springand negligible in November. At one of the threesites measurements were performed in campaignsin 3 consecutive years. Comparison of theemission levels in the first and second yearshowed a reduction of the methane emission ofabout 50% due to implementation of a gasextraction system. From the second to the thirdyear emissions increased by a factor of 4 due tonew landfilling. Furthermore measurements wereperformed in winter when oxidation efficiencywas reduced. This paper describes themeasurement technique used, and discusses theresults of the experimental sessions that were performed. 相似文献
540.
Examining Source-Receptor Relationships for Mercury in Scandinavia Modelled and Empirical Evidence 总被引:1,自引:0,他引:1
Munthe John Kindbom Karin Kruger Olaf Petersen Gerhard Pacyna Jozef Iverfeldt Åke 《Water, Air, & Soil Pollution: Focus》2001,1(3-4):299-310
The atmosphere remains the major source of mercuryin Swedish ecosystems. Since the late eighties,atmospheric emissions of mercury have drasticallydecreased in Europe. Wet deposition of mercury hasdecreased over the last decade but still exhibitsa clear south-to-north gradient, greatlyinfluenced by source areas in northern and centralEurope. The decreases in emissions can beattributed to both direct measures to close knownpoint sources and a declining economy and energyconsumption in many East European countries.Further reductions of mercury emissions willrequire that other source categories such asindirect emissions from mercury-containingproducts and crematories are be considered. 相似文献