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建立了顶空-气相色谱法测定固定污染源废气中三甲胺的分析方法。弱酸性吸收液采集固定污染源废气中的三甲胺,碱液中和后顶空进样气相色谱仪氮磷检测器分析。并对平衡温度、平衡时间、盐析效应、氨水和氢氧化钠条件实验进行优化,在最佳实验条件下,三甲胺的方法检出限为0. 46μg/m~3(以采集20 L空气样品计),加标回收率为97%~107%,相对标准偏差在9. 26%以下。利用该方法对垃圾焚烧发电厂厂界空气及鱼粉厂有组织废气中三甲胺进行检测分析,该方法能够满足国家标准及上海地方标准中三甲胺排放限值的要求。 相似文献
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Akira KONDO Esrom HAMONANGAN Satoshi SODA Akikazu KAGA Yoshio INOUE Masaharu EGUCHI Yuta YASAKA 《环境科学学报(英文版)》2007,19(6):709-713
Total suspended particulate mater (TSP) concentrations were monitored for one year from July 2000 and for one year from April 2003 in Jakarta City. Thirteen elemental TSP components, aluminum (Al), sodium (Na), iron (Fe), lead (Pb), potassium (K), zinc (Zn), titanium (Ti), manganese (Mn), bromine (Br), copper (Cu), chromium (Cr), nickel (Ni), and vanadium (V) were analyzed by a sequential X-ray fluorescence spectrometer. Al, Na, Fe, K, and Pb were major components at most of the sampling locations in 2000. However, only Pb in 2003 dramatically decreased to one tenth. The phase-out of leaded gasoline began on July 1, 2001 in Jakarta City and lead content in gasoline decreased to one tenth, too. The decrease in Pb concentration was a result of the phase-out of leaded gasoline, as lead emissions mainly are exhaust gas from vehicles. 相似文献
45.
Seyfi Polat Ahmet Uyumaz Emre Yilmaz Tolga Topgül H. Serdar Yücesu 《International Journal of Green Energy》2016,13(1):63-70
EGR is one of the most significant strategies for reducing especially nitrogen oxides (NOx) emissions from internal combustion engines. The thermal efficiency of spark ignition engines is lower than compression ignition engines because of its lower compression ratio. If the compression ratio is increased to obtain higher thermal efficiency, there may be a knocking tendency in spark ignition engines. EGR can be used in order to reduce NOx emissions and avoid knocking phenomena at higher compression ratios. In-cylinder temperature at the end of combustion is decreased and heat capacity of fresh charge is increased when EGR applied. Besides EGR, spark timing is another significant parameter for reducing exhaust emissions such as nitrogen oxides, and unburned hydrocarbon (UHC). In this study the effects of EGR and spark timing on spark ignition engine were investigated numerically. KIVA codes were used in order to model combustion process. The combustion process has been modeled for a single cylinder, four stroke and gasoline direct injection (GDI) spark ignition engine. The results showed that in-cylinder pressure and heat release rate decrease as EGR ratio increase. In-cylinder pressure increases with the advancing of spark timing. Advancing spark timing increases the heat release rate and in-cylinder temperature. The simulation results also showed that EGR reduced exhaust gas temperature and NOx emissions. 相似文献
46.
Giorgio Zamboni Silvia Marelli Giulio Marmorato Massimo Capobianco 《International Journal of Green Energy》2016,13(5):481-488
A cooperative fuel research (CFR) engine was modified and instrumented in order to control operating conditions and to measure engine parameters and in-cylinder pressure diagrams. Aiming at the comparison of different alternative fuels, an experimental procedure was defined, including cetane number (CN) evaluation and the definition of engine operating quantities in different working points, for fixed levels of compression ratio (CR) and injection advance. An investigation was made considering several blends of methyl-esters of rapeseed oil (RME) and of a mix of vegetable oils (VOME) with conventional diesel oil. The defined experimental procedure was applied to assess CN, engine brake thermal efficiency (bte) and exhaust emissions. Results show that the biodiesel content has a positive influence on soot emissions, with strong reduction, while thermal efficiency and NOX emissions are negatively affected, which can be justified taking into account fuel properties and changes in combustion process. As observed outcomes are generally in line with those presented in literature, the facility proved to be a suitable tool for basic investigations on alternative fuels to be used in specific applications. 相似文献
47.
模拟了车用工况下燃料电池发动机脉冲式排氢的特点,设计开发了一套质子交换膜燃料电池的尾气净化系统,并以5 kW燃料电池的尾气排放为例,研究其净化效果。研究了电池阳极排放氢气缓冲前后尾气中氢气浓度的变化,以及不同空速条件下氢气的去除效果。结果表明:电堆阳极排放氢气经过缓冲处理后,尾气中氢气浓度趋于平稳,大部分工况下处在2%以下,达到了安全处理的要求;尾气中氢气的去除效果与空速密切相关。对自制的整体式催化剂而言,当空速低于20000 h^-1时,氢气的去除率能达到约95%,而当空速达到39270 h^-1时,氢气的去除率仅为10.9%。鉴于这一问题,提出通过采用尾排空气的分流手段调整催化燃烧反应器对空速的要求,以提高尾气中氢气的去除率。 相似文献
48.
This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach. 相似文献
49.
应用CALINE4模式估算机动车排放污染物的浓度——以济南市主干道为例 总被引:1,自引:0,他引:1
随着经济的快速发展,机动车排气污染已成为我国城市空气污染的重要来源,而且在一定时段,机动车排气污染已成为空气污染最主要的污染源之一。以济南市经十路为例,采用实地调查的方法,得出各时段的车流量,选用大气环评助手EIAA中的CALINE4模式对机动车尾气中的主要污染物CO、NOx、THC的排放浓度进行估算,得出3种污染物CO、NOx、THC最大值均出现在7:00—8:00之间,最小值均出现在12:00-13:00之间,排放强度由大到小为:CO、THC、NOx。 相似文献
50.
以电解锰阳极泥与电解锌生产中产生的含SO_2尾气为原料,经过反应、浸出、浸出液两次净化和浓缩结晶制备硫酸锰,考察了反应时间、含SO_2尾气的流量及反应温度对Mn~(4+)转化率的影响.实验结果表明:在反应时间45 min、反应温度20~30 ℃、含SO_2尾气流量16 L/min的条件下,Mn~(4+)转化率达90%以上;尾气中SO_2利用率随尾气流量增加而降低;所得MnSO_4·H_2O产品质量达到GB1622-86<工业级硫酸锰标准>. 相似文献