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991.
农村居民煤炭消费牵涉到农村居民生活方式与能源转型、北方供暖清洁化改革、大气污染治理等重大改革实践,如何准确理解和研判现有的农村居民煤炭消费现状,并进而识别出科学、有效的减煤措施,已成为改善农村居民能源结构、治理农村地区煤炭消费、改善北方地区大气质量的重要手段之一。然而,现有对农村居民煤炭消费的统计数据可能存在一定低估,基础性数据的匮乏与不足严重阻碍了科学研究和公共决策。为了准确了解我国农村居民煤炭消费的现状、特征与空间分布,本文采用第三次中国家庭能源消费调查数据对农村居民的煤炭消费进行了核算,并针对户均煤炭消费量和地区农村居民煤炭消费总量进行了比较,在此基础上还考察了气候差异、资源禀赋、收入水平等因素对农村居民煤炭需求的影响。研究结果表明,2014年中国农村居民生活用煤炭消费总量为6 585.7万tce,平均每户煤炭消费量为347.2 kgce,其中供暖用煤占比96.9%,烹饪用煤占比3.1%。各省的户均煤炭消费和煤炭消费总量呈现显著的空间差异,其中:东北、西部地区农村居民户均煤炭消费量显著高于其他地区,北京及周边的河北、山东、山西、内蒙、辽宁和天津7个省、市的农村居民共消费了全国55%的农村生活用煤,其中北京周边的河北、山东和山西三省农村居民消费了全国46.6%的农村煤炭消费。地区煤炭资源禀赋、农村居民住房面积与供暖用煤需求显著正相关,而冬季户外温度、居民收入水平同煤炭需求之间关系不显著。未来政府应通过改善农村居民民生需求、推动农村能源转型、提高农村能源统计水平等途径来有效治理农村散煤消费。 相似文献
992.
化学循环燃烧载氧体的研究进展 总被引:1,自引:0,他引:1
化学循环燃烧是集分离捕集CO2和去除NOx为一体的新型燃烧技术。介绍了化学循环燃烧的发展背景、工艺原理及特点;综述了化学循环燃烧载氧体的选材、载氧体的性能要求,对各系载氧体(如NiO系、Fe2O3系、CuO系、CoO系和Mn2O3系载氧体)的性能进行了对比分析;提出了Fe2O3、Fe2O3/Al2O3(质量分数为60%的Fe2O3+质量分数为40%的Al2O3)、NiO/NiAl2O3(质量分数为50%的活性NiO+质量分数为50%的NiAl2O3)是当前的优势载氧体,并对载氧体的发展做了展望。 相似文献
993.
994.
HAO Li-qing WANG Zhen-y FANG Li ZHANG Wei-jun WANG Wei LI Cheng-xiang SHENG Liu-si 《环境科学学报(英文版)》2006,18(5):903-909
Photooxidation reaction of toluene in smog chamber systems was initiated by the UV radiation of tolucne/CH5ONO/NOx mixtures. The products of the photooxidation reaction of toluene and its subsequent reactions were analyzed directly utilizing Fourier transform infrared spectrometer (FTIR). Detailed assignments to FTIR spectrum of gas-phase products were given. The information of some important functional groups in the products, such as, carbonyl groups (C-O), hydroxyl groups (-OH), carboxylic acid (- COOH), C-C bonding, N O bonding and C-H bonding (C H), was got from this analysis. These results were compared to those analyzed by aerosol time of flight mass spectrometer (ATOFMS). It was found that there are some differcnccs between FTIR analysis of gas-phase products and that of particle-phase, for example, the products with carbonyl groups, which were connected to unsaturated chemical bonds, was relatively higher in the gas phase, while kctoncs, aldehydes, carboxylic acid and organonitrates were the dominant functional groups in the aerosol-phase reaction products. The possible reaction pathways of some important products in the gas phase were also discussed. 相似文献
995.
Recent measurements at different locations suggest that the emission of mercury from soils may play a more pronounced role in the global mercury cycle as suggested by global emission inventories and global mercury cycling models. For up scaling and modelling of mercury emissions from soils a comprehensive assessment of the processes controlling the emission of mercury from soils is imperative. We have developed a laboratory flux measurement system (LFMS) to study the effect of major environmental variables on the emission of mercury under controlled conditions. We have investigated the effects of turbulent mixing, soil temperature and solar radiation on the emission of mercury from soils. The emission of mercury from soils is constant over time under constant experimental conditions. The response of the mercury emission flux to variations of the atmospheric transfer parameters such as turbulence requires a rapid adjustment of the equilibrium that controls the Hg(o) concentration in the soil air. It has been shown that the light-induced flux is independent of the soil temperature and shows a strong spectral response to UV-B. 相似文献
996.
997.
W. Z. Khan 《Environmental monitoring and assessment》2001,71(2):123-142
The reduction of SO2 by ammonia gas additionduring staged combustion of bituminous coal has beenstudied in a 2 m high fluidized bed combustor of 30 cmstatic bed height and a freeboard height of 100 cm.The coal was introduced to the combustor at 42 cmabove the distributor and the ammonia gas was injectedat 52 cm above the distributor by an uncooledstainless steel injector. Experiments were carriedout to investigate effects of ammonia gas injection onSO2 emissions of (i) air staged levels, (ii) excess air levels, (iii) primary air factor, PAF(ratio of primary to stoichiometric air), (iv) NH3:SO2 molar ratio, and (v) fluidizingvelocity. Experiments were carried out under a newtechnique of air staging called Pseudo-stagedCombustion, maintaining the excess air level andfluidizing velocity between 17 and 70% and between0.7 and 2.0 m sec-1, respectively. A maximum reduction of92% was obtained at 37% excess air, at NH3:SO2 molar ratio of 5.5. The effective NH3:SO2 molar ratio was found to be between 3.0 and5.5, which is true for all staging and excess air levels.A greater removal of SO2 with NH3 injectionduring staged combustion is probably due to this newstaging technique. The Pseudo-staging reducestemperature through the freeboard and flue for theoccurance of as NH3 + SO2 reactions. Thesereactions are reported to be low temperaturereactions. The NH3 carry over was less than 83 ppm for all operating conditions. The present studydemonstrates that staged combustion coupled withammonia injection can reduce SO2 emissions. 相似文献
998.
利用气相色谱/燃烧/同位素比值质谱(GC/C/IRMS)分析技术,采用NaHSO3与半胱胺衍生化方法,测定了气态乙醛在衍生化反应过程中的碳同位素效应,探讨了采用该方法测定大气乙醛碳同位素组成的可行性。试验测定了乙醛、衍生剂半胱胺及相应衍生物的碳同位素比值,结果表明,乙醛衍生物的δ13C测量值与理论值的偏差范围为0.11‰~0.35‰,在仪器精密度范围内(<0.50‰),即在衍生化过程中基本不会发生碳同位素分馏。采用该方法初步测定了大气中乙醛的碳同位素组成,实测数据显示,广州地化所和肇庆鼎湖山大气乙醛δ13C平均值分别为(-34.21±0.27)‰和(-31.23±0.16)‰,相同采样点的大气乙醛碳同位素组成基本不变,可见该方法可作为研究大气乙醛不同排放源的一种有效方法。 相似文献
999.
1000.
Eva Leotz-Gartziandia Véronique Tatry Patrick Carlier 《Environmental monitoring and assessment》2000,65(1-2):155-163
The fraction of atmospheric semi-volatile organic compounds (SVOC) is partitioned between the gaseous and particulate phases. Certain of these compounds eg. polynuclear aromatic hydrocarbons (PAH) and their derivatives have been shown to exhibit mutagenic or carcinogenic properties. Emissions from diesel engines are an important source of these contaminants. In a dilution chamber, we studied a diesel engine emissions. It is shown firstly, that the gaseous fraction is predominant (by up to 20 times) with respect to the particulate phase. Secondly, the polar compounds, neglected in the majority of previous studies, are the predominant species. A test campaign was carried out in Paris-Porte d'Auteuil which yielded similar results to the laboratory experiments. 相似文献