离子色谱法测定废气中的甲酸和乙酸

阐述了离子色谱法测定废气中甲酸、乙酸含量的方法和步聚。甲酸、乙酸检出限分别为0.02mg/L和0.05mg/L,方法平均回收率分别为92%和95%。本方法分析速度快,所需样品量少,且无需复杂的前处理。     

地铁车厢机械排烟和细水雾耦合灭火效果研究

采用火灾动力学软件FDS（FireDynamicSimulator）,以封闭单节地铁列车车厢为研究对象,模拟分析不同喷雾速度、排烟量以及排烟启动时刻条件下,车厢内火灾热释放速率、烟气层高度、烟气层温度的变化规律,对细水雾和机械排烟耦合作用下地铁列车车厢火灾灭火效果展升研究。结果表明,喷雾初速度较小时,细水雾动作之后启动排烟系统的灭火效果更好;喷雾初速度较大时,细水雾动作之前启动排烟系统的灭火效果更好;同样的喷雾初速度条件下,增大排烟量町以提高烟气层高度和降低烟气层温度,排烟量过大可能造成火焰区的扰动,降低细水雾的火火效果。     

排烟口布置方式对高层建筑火灾排烟效果的影响

高层建筑发生火灾时,烟气对人员的生命安全有着非常大的威胁,因此有效地控制烟气在建筑物内的扩散对于人员的逃生是非常重要的。通过高层建筑内烟气流动的数学模型,采用k-ε两方程三维紊流模型对高层建筑火灾时排烟口布置于走廊顶棚和走廊侧壁时的机械排烟进行模拟。结果表明,排烟口的布置方式不同对排烟效果的影响很大。排烟口置于顶棚时比排烟口置于侧壁时排烟效率高近10％,走廊内危险性低。在进行排烟设计时应优先考虑将排烟口设置在走廊顶部。     

汽油无铅化与环境空气中铅污染的变化趋势

文章简要分析了 1 998年天津市环境空气及交通环境空气中铅污染的程度。机动车尾气排放是环境空气及交通环境空气中铅污染的重要来源 ,1 998年机动车推广使用无铅汽油后天津市铅污染状况明显减轻。     

Emission and Performance Characteristics of a 2 Litre Toyota Diesel Van Operating on Esterified Waste Cooking Oil and Mineral Diesel Fuel

Exhaust emission and performance characteristics were evaluated in a Toyota van, powered by a 21 indirect injection (IDI) naturally aspirated diesel engine, operating on vegetable based waste cooking oil methyl ester (WCOME).Tests were performed on a chassis dynamometer and the data were compared with previous results conducted on the same vehicle using mineral diesel fuel. The data obtained includes smoke opacity, carbon monoxide (CO), carbon dioxide (CO₂), oxygen (O₂), nitrogen dioxide (NO₂), nitric oxide (NO), sulfur dioxide (SO₂) and brake power. Engine lubricating oil samples were also taken. Results from this study indicated a difference of approximately 9% in brake power between the two fuels. WCOME developed a significant lower smoke opacity level and reduced CO, CO₂, SO₂ emissions. However, O₂, NO₂ and NO levels were higher with the vegetable oil based fuel. Power values were comparable for both fuels. Lubricating oil analysis gave little change of viscosity and wear metal concentrations after 2887km were: Silicon 35ppm, Chromium 3.3ppm, Iron 33.8ppm, Copper 14.1ppm and lead 78.6ppm.     

城市汽车尾气污染治理模式探讨

借鉴国内外 I/ M制度的经验 ,运用系统论、控制论的观点 ,创造性地提出有效治理城市汽车尾气污染应建立的六大体系 ,强调城市汽车尾气污染的控制应以尾气污染预前控制和过程控制为主 ,并以此构筑城市汽车尾气污染治理的新模式     

分光光度法测定大气颗粒物和柴油尾气中的砷含量

介绍了测定砷含量的分光光度法,该方法可以应用于大气颗粒物中的痕量砷的敏感性测定。测定、考察了北方城市大气中砷浓度及日变化规律,结果表明,分光光度法显色稳定,灵敏度高。将此方法获得的结果与原子吸收法所得到的结果进行比较,两者高度吻合。进行了柴油机动车尾气中砷含量的测定,结果表明,其尾气中含有一定量的砷。     

导电泡沫陶瓷过滤柴油机排气微粒的研究

柴油机排气微粒对环境危害严重,研究开发排气过滤技术是解决问题的有效措施之一.利用表面密集排列短纤维的导电泡沫陶瓷作为微粒过滤器的滤芯,对柴油机排气微粒的过滤效率可达90%,并可进行原位通电加热再生,再生后过滤效率不下降.同时,对表面纤维化导电泡沫陶瓷的过滤机理进行了初步探讨.     

Combustion performance and emission characteristics on HCCI engine of waste plastic pyrolysis oil biodiesel blends with external PFI and vaporiser

ABSTRACT

Analysis of plastic oil obtained from waste plastic through pyrolysis process, as an alternative to biodiesel is presented in this paper. The HCCI engine is considered for experimental validation of combustion performance and emission characteristics. To accumulate pyrolysis oil as fuel, the design modifications were made in external mixture formation on the existing computerised 4-stroke, single cylinder, water cooled, direct injection kirloskar diesel engine connected with eddy current dynamometer to satisfy HCCI conditions. HCCI engine can be worked on wide assortment of fuels beginning from diesel to different blends (WPPO 5%,10%,15% and 20% by volume) of biodiesel .The designed additional device connected to the engine is utilised for fuel vaporisation and mixture arrangement. In the experimental study, the combustion results were initiate to be of 39.69 % higher Rate of Heat Release (RoHR) for biodiesel HCCI as compared with diesel HCCI. Higher brake thermal efficiency (BTE) was found 37 % without exhaust gas recirculation (EGR) at WPPO 20 % biodiesel blend. And also found 50 % and 65 % reduction in NOx emission and 18 % and 28 % reduction in smoke opacity are obtained for biodiesel vapour induction without EGR and biodiesel vapour induction with 15 % EGR as compared with diesel fuel. The CO (0.34 %), and UHC (2.15 %) emissions are increases with 15 % EGR, but the emissions are within the standard limits specified by the emissions standards.     

铀矿井排风口尾气对周边农田土壤放射性污染的预测

铀矿井尾气排风口周围土壤中放射性物质的累积性污染不容忽视,但目前处于监测和积累数据阶段.在对指数平滑法综合应用分析研究的基础上,根据某铀矿井排风口周边某一农田土壤中近10 a的铀(238U)质量比监测数据建立了指数平滑预测模型,对土壤放射性铀(238U)污染进行预测,并对预测结果进行了深入分析,精度达75%以上.预测结果表明,采用指数平滑法建立土壤放射性污染预测模型是可行的,具有一定的应用价值.铀矿井排风口尾气对周边土壤的放射性累积性污染呈逐年递增趋势,迫切需要采取一些切实可行的控制措施.