中国生物质燃烧大气污染物排放清单

根据2000-2007年各省市生物质燃烧消耗量和排放因子,估算了中国大陆生物质燃烧所导致的NOx、SO2、CO、CO2、CH4、NMHC、PM、BC排放量,并给出了分省区、分生物质类型的排放清单.研究表明,2007年中国生物质燃烧排放的NOx、SO2、CO、CO2、CH4、NMHC、PM和BC排放量分别为109万t,1...     

低浓度SO2和NOx自动监测系统性能评价方法

通过对7种废气自动监测系统的比较研究和现场测试,提出了非分散红外法、紫外差分法、紫外荧光法、化学发光法等多种SO2和NO x自动监测技术在低浓度范围实现准确定量监测的性能评价方法,定义了CEMS的系统检出限及其主要影响因素。建议采用系统检出限、线性误差等关键参数作为低浓度CEMS的性能评价方法,提出将全系统多点标准气体校准或加标回收率作为验收和质控监督的基本方法。     

2005年陕西秋淋特征分析

通过对2005年陕西秋淋特征分析认为,2005年陕西秋淋明显且偏晚,降水强度大,落区广且地区较集中;秋淋造成渭河下游、汉江干流分别出现了1981年、1983年以来最大的洪峰.西太平洋副热带高压强盛稳定及适当的副高脊线位置和西伸脊点位置是秋淋期间强降水集中的主要原因,而2005年的台风活动也为陕西秋淋天气提供了有利的气候背景.     

三种农作物秸秆燃烧颗粒态多环芳烃排放特征

收集3种农作物秸秆玉米,水稻和小麦露天燃烧排放的颗粒物样品,并利用气相色谱-质谱(GC-MS)对样品中的34种多环芳烃(PAHs)进行分析,研究颗粒态PAHs的排放因子及可用于源解析的诊断参数.结果表明,3种秸秆燃烧总PAHs的排放因子为644.18~1798.13μg/kg;其中4环PAHs在秸秆燃烧样品中含量最高,约占38.8%~58.8%,6环PAHs所占比例相对较小,约占5.72%~15.17%.PAHs中部分单体具有相对较强致癌性,对环境和人体健康的影响不可忽视.首次检测分子量为300的高分子多环芳烃二苯并[a,e]荧蒽.在玉米、水稻和小麦秸秆燃烧排放颗粒物中的排放因子分别为6.70,2.77和2.92μg/kg.此外,研究发现BaP/BghiP, Phe/Phe+Ant和Flu/(Flu + Pyr)比值可以作为较好的区分秸秆燃烧与其他来源的诊断参数.     

广州市区广播电视发射塔电磁辐射调查

为了解广州市区广东电视发射塔和广州电视发射塔电磁辐射状况，广州市环境监测中心站对电视发射塔周围的环境进行了监测。结果表明．两座电视发射塔周围电磁辐射水平随着距离的增加，呈现下降的趋势；两座广播电视发射塔周围高层建筑敏感点窗外电磁辐射水平随着楼层的增加．呈现上升的趋势。     

Preparation and emission characteristics of ethanol-diesel fuel blends

The preparation of ethanol-diesel fuel blends and their emission characteristics were investigated. Results showed the absolute ethanol can dissolve in diesel fuel at an arbitrary ratio and a small quantity of water(0.2% ) addition can lead to the phase separation of blends. An organic additive was synthesized and it can develop the ability of resistance to water and maintain the stability of ethanol-diesel-trace amounts of water system. The emission characteristics of 10%, 20%, and 30% ethanol-diesel fuel blends, with or without additives, were compared with those of diesel fuel in a direct injection(DI) diesel engine. The experimental results indicated that the blend of ethanol with diesel fuel significantly reduced the concentrations of smoke, hydrocarbon(HC), and carbon monoxide(CO) in exhaust gas. Using 20% ethanol-diesel fuel blend with the additive of 2% of the total volume, the optimum mixing ratio was achieved, at which the bench diesel engine testing showed a significant decrease in exhaust gas. Bosch smoke number was reduced by 55%, HC emission by 70%, and CO emission by 45%, at 13 kW/1540 r/min. However, ethanol-diesel fuel blends produced a few ppm acetaldehydes and more ethanol in exhaust gas.     

“2+26”城市秋冬季大气污染治理措施效果评估

针对京津冀及周边"2+26"城市秋冬季不同大气污染治理措施的减排量进行核算,结果表明,2017~2018年秋冬季"2+26"城市SO₂,NO_x,VOCs,PM_2.5和PM₁₀的总减排量分别为43.26,20.63,18.36,28.00和47.31万t,2018~2019年秋冬季"2+26"城市SO₂,NO_x,VOCs,PM_2.5和PM₁₀的总减排量分别为16.68,18.11,11.03,17.04和25.33万t.基于此,采用CAMx模型对各项措施的减排效果进行模拟评估,采取措施后,2017~2018年秋冬季"2+26"城市SO₂,NO_x,PM_2.5和PM₁₀浓度的平均下降量（下降率）分别为22.69μg/m³（42.67%）,33.22μg/m³（37.81%）,24.28μg/m³（22.58%）和31.26μg/m³（18.67%）,2018~2019年秋冬季"2+26"城市SO₂,NO_x,PM_2.5和PM₁₀浓度的平均下降量（下降率）分别为9.36μg/m³（26.86%）,25.73μg/m³（30.62%）,16.38μg/m³（16.09%）和20.43μg/m³（12.33%）.2017~2018年秋冬季各项措施对PM_2.5浓度的平均减排效率排序依次为："散乱污"企业治理 > 交通运输结构调整 > 企业错峰生产 > 民用散煤替代 > 燃煤锅炉综合整治,2018~2019年秋冬季各项措施对PM_2.5浓度的平均减排效率排序依次为：重点行业升级改造 > 企业错峰生产 > "散乱污"企业治理 > 交通运输结构调整 > 民用散煤替代 > 燃煤锅炉综合整治.     

火电厂二氧化硫排放行为分析

火电厂是二氧化硫排放大户。从企业层面和国家层面上对火电厂二氧化硫排放行为和形势进行了分析和总结,以期为环境管理服务。     

我国轻型汽车污染物排放因子的测试研究

采用底盘测功机按ＥＣＥ－１５规程测试了我国１３辆（１２种）正在使用的轻型汽车的ＣＯ、ＨＣ和ＮＯｘ的排放量分别为８７．２５±５６．３１、１１．３６±５．１３和８．２０±６．６８ｇ／ｔｅｓｔ;在相同测试条件下,测试了其中１１种轻型车在不同车速匀速行驶时的ＣＯ、ＨＣ和ＮＯｘ排放因子．测试结果表明、轻型汽车污染物排放因子随车速的变化有良好的规律性．用统计方法拟合了轻型汽车污染物排放因子的车速变化系数的计算公式。当车速＜９０ｋｍ／ｈ时,轻型车ＣＯ、ＨＣ排放因子随车速的增加而减小,当车速＞９０ｋｍ／ｈ时,又略有增加,而ＮＯｘ排放因子随车速的增加而增大。     

Raman spectroscopy of diesel and gasoline engine-out soot using different laser power

We studied engine-out soot samples collected from a heavy-duty direct-injection diesel engine and port-fuel injection gasoline spark-ignition engine. The two types of soot samples were characterized using Raman spectroscopy with different laser powers. A Matlab program using least-square-method with trust-region-reflective algorithm was developed for curve fitting. A DOE (design of experiments) method was used to avoid local convergence. The method was used for two-band fitting and three-band fitting. The fitting results were used to determine the intensity ratio of D (for “Defect” or “Disorder”) and G (for “Graphite”) Raman bands. It is found that high laser power may cause oxidation of soot sample, which gives higher D/G intensity ratio. Diesel soot has consistently higher amorphous/graphitic carbon ratio, and thus higher oxidation reactivity, compared to gasoline soot, which is reflected by the higher D/G intensity ratio in Raman spectra measured under the same laser power.