家具涂料的挥发性有机物排放特征及致癌风险估算

采用顶空实验装置采集家具涂料挥发蒸汽,通过不锈钢采样罐-气相色谱(GC)/质谱(MS)分析系统测量了溶剂型和水型涂料的挥发性有机物(VOCs)排放特征。结果表明,溶剂型涂料排放的总VOCs平均质量浓度为7.6mg/m3,远高于水型涂料的2.6mg/m3。溶剂型和水型涂料排放的VOCs主要以芳香烃和烷烃为主。溶剂型涂料和水型涂料排放的特征VOCs组分为甲苯、2-甲基戊烷、苯、正辛烷,分别占两种涂料总VOCs排放的41.8%(质量分数,下同)和31.2%、21.2%和9.6%、6.5%和5.6%、6.0%和4.8%。溶剂型涂料排放VOCs的臭氧生成潜势(OFP)和二次气溶胶生成潜势(SOAP)明显高于水型涂料,OFP和SOAP的主要贡献组分均为芳香烃物质。溶剂型涂料排放的苯的长期致癌风险是水型涂料的2.6~4.6倍,均远远高于可接受的暴露风险值1×10-6。     

活性炭纤维净化印刷过程产生的VOCs废气

介绍了应用局部排气的方法,收集印刷过程的挥发性有机化合物(VOCs)废气,应用活性炭纤维(ACF)吸附脱附有机废气回收净化装置,进行印刷厂VOCs废气的回收与治理,详细描述了印刷车间VOCs废气的收集与处理工艺过程及其效果.测试结果表明,应用此工艺和设备可以有效地进行印刷过程大风量的VOCs废气的回收和治理.     

典型石化企业挥发性有机物排放测算及本地化排放系数研究

石化行业是中国大气挥发性有机物(VOCs)的重要来源。以中国某新建典型石化企业为例,综合采用不同核算方法估算并比较了石化企业典型排放环节VOCs的排放结果;并在此基础上计算了石化企业典型排放环节本地化排放系数。结果表明,典型石化企业各环节VOCs排放量贡献分别为:储罐50.4%、废水收集与处理29.0%、火炬8.3%、装卸5.2%、设备密封点3.4%、循环冷却水2.4%、燃烧烟气0.8%、工艺废气0.5%;在装卸、设备密封点、废水收集与处理、循环冷却水环节,不同核算方法造成核算结果差异较大,排放系数法核算结果为本研究方法核算结果的数倍,其中装卸过程为4.2倍(无回收设施)和16.4倍(含回收设施),设备密封点为4.4倍(泄漏筛分法)和55.4倍(相关方程法),废水收集与处理为2.1倍,循环冷却水为2.1倍;《大气挥发性有机物源排放清单编制技术指南》中石油炼制企业的VOCs排放系数为本研究1.8倍,因此石化企业在建立排放清单时应开展本地化研究,建立本地化系数;研究结果对于中国建立石化企业VOCs排放清单提供了一定支撑。     

化学原料药行业挥发性有机废气污染特征与治理中的主要问题及建议

化学原料药制造行业是挥发性有机废气(VOCs)排放重点监管行业。原料药生产过程中VOCs排放具有排放节点多、成份复杂等特点。在阐述典型原料药生产过程中VOCs产生环节的基础上,分析了制药企业VOCs治理普遍面临的治理技术缺乏针对性、无组织废气收集不足、企业废气自行监测能力不足等难点问题,并对制药企业VOCs治理提出了加强有机废气成分溯源监测和规范废气收集等前瞻性建议,以期为提高该行业的VOCs治理效果并促进制药行业的可持续发展提供参考。     

油品装车栈桥区域挥发性有机物治理方案研究

挥发性有机物(VOCs)是石化行业的特征污染物,油品装车栈桥的VOCs无组织挥发是石化企业重要的VOCs排放源,因此对大型石化企业油品装车栈桥区域的VOCs进行治理减排具有十分重要的意义。以西北某石化公司油品装车栈桥VOCs无组织挥发治理项目为例,通过源强核算、削减方案确定,利用AERMOD模式对栈桥区域环境空气质量改善情况进行预测分析,进而对VOCs治理方案的环境收益进行讨论,以期为同类油品装车栈桥改造项目提供借鉴与参考。     

广州市工业挥发性有机物排放特征研究

伴随着工业经济的高速发展,广州市大气环境面临的压力日益增大,尤其是挥发性有机物( VOCs),可经过复杂的大气化学反应,引起一系列严重的空气质量问题.以源头追溯的方法,将该区域工业相关的33个VOCs排放源按照物质流动过程分为4个环节,分析了其排放特征.结果表明,2008年VOCs排放总量为182 362.7 t,各环节的贡献率分别为:VOCs的生产环节34.5％、储存和运输环节18.4％、以VOCs为原料的工艺环节9.9％、VOCs产品的使用和排放环节37.2％;污染主要来自石油炼制与石油化工、油品储运、交通运输设备制造与维修等,前12大污染源的VOCs排放量共占2008年排放总量的87.3％.2006-2008年的VOCs排放总量均超过15万t,且呈逐年增长的趋势.该研究可为“十二五”期间珠三角VOCs污染物联防联治工作提供借鉴.     

成都市冬季重污染过程中挥发性有机物污染特征及来源解析

采用大气挥发性有机物(VOCs)在线监测系统对成都市冬季重污染过程的VOCs进行了连续在线观测,用正交矩阵因子分解(PMF)模型开展了VOCs源解析工作,并对重污染成因进行了分析。结果表明:观测期间成都市总VOCs(TVOCs)体积分数为21.83×10~(-9)～183.59×10~(-9),平均值为54.17×10~(-9),TVOCs中烷烃浓度最高,其次为炔烃、烯烃、芳香烃和卤代烃;成都市主要VOCs污染源为机动车排放源、液化石油气燃烧排放源、工业源、生物质燃烧源和溶剂使用源,贡献率分别为34.15%、21.57%、19.08%、15.19%、10.02%;边界层压缩和静风条件可能是导致VOCs和PM2.5浓度增加的主要原因。     

四川省制鞋行业挥发性有机物成分谱研究

为探究四川省制鞋行业挥发性有机物(VOCs)的主要组分,通过现场采样的方法,对四川省整鞋制造、中大底制造、改性橡胶鞋底制造、橡胶鞋底制造、鞋跟制造以及鞋模制造6种制鞋类型企业排放的VOCs进行了采样分析。结果表明:四川省制鞋行业的VOCs成分谱中,含氧化合物和烷烃含量最高。有组织VOCs排名前三的组分为丙酮、二氯甲烷、甲苯,质量分数分别为30.82%、16.04%、11.06%;无组织VOCs排名前三的组分为正戊烷、丙酮、2-甲基戊烷,质量分数分别为20.26%、17.10%、10.31%。     

活性炭纤维净化印刷过程产生的VOCs废气

介绍了应用局部排气的方法,收集印刷过程的挥发性有机化合物（VOCs）废气,应用活性炭纤维（ACF）吸附脱附有机废气回收净化装置,进行印刷厂VOCs废气的回收与治理,详细描述了印刷车间VOCs废气的收集与处理工艺过程及其效果.测试结果表明,应用此工艺和设备可以有效地进行印刷过程大风量的VOCs废气的回收和治理.     

绍兴城区夏季大气挥发性有机物特征、来源及大气反应活性

研究了2019年夏季(8月)绍兴城区的烷烃、烯烃、炔烃、芳烃、卤代烃、含氧挥发性有机物(VOCs)、腈7类共98种VOCs的特征、来源及大气反应活性。结果表明,7类VOCs的平均质量浓度由大到小依次为烷烃(24.29μg/m3)卤代烃(17.17μg/m3)芳烃(15.89μg/m3)含氧VOCs(14.72μg/m3)烯烃(4.06μg/m3)炔烃(1.23μg/m3)腈(0.27μg/m3)。烃、腈和卤代烃白天浓度低,夜间浓度高,含氧VOCs基本上终日保持稳定。白天交通排放的贡献较为显著;夜间除交通排放外,挥发性有机溶剂的使用对绍兴城区夏季VOCs也有重要影响。此外,VOCs在一定程度上受到了长距离气团传输的影响,也存在一定的老化现象。烯烃、芳烃是绍兴城区夏季最具大气反应活性的VOCs。     

天津市挥发性有机物污染特征与来源及其O3生成潜势

为深入了解天津市大气挥发性有机物(VOCs)来源及对O3的影响,基于2020年天津市VOCs在线监测数据,统计分析了VOCs污染特征,用主成分分析法对天津市VOCs的来源进行解析,用最大增量反应活性法分析VOCs的O3生成潜势(OFP).结果表明:2020年天津市VOCs的年均质量浓度总和为56.56μg/m3,其中,...     

Source profiles of volatile organic compounds associated with solvent use in Beijing,China

Compositions of volatile organic compound (VOC) emissions from painting applications and printing processes were sampled and measured by gas chromatography–mass spectrometry/flame ionization detection (GC–MS/FID) in Beijing. Toluene and C8 aromatics were the most abundant species, accounting for 76% of the total VOCs emitted from paint applications. The major species in printing emissions included heavier alkanes and aromatics, such as n-nonane, n-decane, n-undecane, toluene, and m/p-xylene. Measurements of VOCs obtained from furniture paint emissions in 2003 and 2007 suggest a quick decline in benzene levels associated with formulation changes in furniture paints during these years. A comparison of VOC source profiles for painting and printing between Beijing and other parts of the world showed significant region-specific discrepancies, probably because of different market demands and environmental standards. We conducted the evaluation of the source reactivities for various VOC emission sources. The ozone formation potential (OFP) for unit mass of VOCs source emissions is the highest for paint applications. Substituting solvent-based paints by water-based in Beijing will lead to an OFP reduction of 152,000 tons per year, which is more than 1/4 of the OFPs for VOCs emissions from vehicle exhaust in the city.     

A study on dynamic volatile organic compound emission characterization of water-based paints

Volatile organic compounds (VOCs) emitted from surface coatings have caused growing public concern for air quality. Even the low-emitted VOC impact from water-based paints on indoor air quality in urban areas has caused concern. This paper presents experimental data using a mathematical model to simulate dynamic VOC emissions from water-based paints that is based on mass transfer and molecular diffusion theories. A series of field-analogous experiments were carried out to continuously measure the VOCs emitted from two typical water-based paints using a gas chromatography-flame-ionization detector monitor in an artificial wind tunnel system. In the study cases, the mass flux of VOCs emitted from the water-based paints was up to 50 microg/m2sec. It was found that the time needed to completely emit VOCs from water-based paints is just hundreds of seconds. However, the order of magnitude of the VOC emission rate from water-based paints is not lower than that from some dry building materials and solvent-based paints. The experimental data were used to produce a useful semiempirical correlation to estimate the VOC emission rates for water-based paints. This correlation is valid under appropriate conditions as suggested by this work with a statistical deviation of +/- 7.6%. With this correlation, it seems feasible to predict the dynamic emission rates for VOCs during a painting process. This correlation is applicable for assessing the hazardous air pollutant impact on indoor air quality or for environmental risk assessment. Associated with the dynamic VOC emission characterization, the air-exchange rate effect on the VOC emission rates is also discussed.     

Destruction of Volatile Organic Compounds Using Catalytic Oxidation

Catalytic oxidation is an air pollution control technique in which volatile organic compounds (VOCs) and vapor-phase air toxics in an air emission stream are oxidized with the help of a catalyst Design of catalytic systems for control of point source emissions is based on stream-specific characteristics and desired control efficiency. This paper discusses the key emission stream characteristics and VOC characteristics that affect the applicability of catalytic oxidation. The application of catalytic oxidation technology to four types of air emission sources is discussed: (1) groundwater stripping operations; (2) graphic arts facilities; (3) flexographic printing plants; and (4) latex monomer production. The characteristics of each of these emissions are discussed along with the catalytic technology used to control these emissions.     

Assessment of control strategies for reducing volatile organic compound emissions from the polyvinyl chloride wallpaper production industry in Taiwan

This study attempts to assess the effectiveness of control strategies for reducing volatile organic compound (VOC) emission from the polyvinyl chloride (PVC) wallpaper production industry. In Taiwan, methyl ethyl ketone, TOL, and cyclohexanone have comprised the major content of solvents, accounting for approximately 113,000 t/yr to avoid excessive viscosity of plasticizer dioctyl phthalate (DOP) and to increase facility in working. Emissions of these VOCs from solvents have caused serious odor and worse air quality problems. In this study, 80 stacks in five factories were tested to evaluate emission characteristics at each VOC source. After examining the VOC concentrations in the flue gases and contents, the VOC emission rate before treatment and from fugitive sources was 93,000 and 800 t/yr, respectively. In this study, the semiwet electrostatic precipitator is recommended for use as cost-effective control equipment.     

Assessment of Control Strategies for Reducing Volatile Organic Compound Emissions from the Polyvinyl Chloride Wallpaper Production Industry in Taiwan

Abstract

This study attempts to assess the effectiveness of control strategies for reducing volatile organic compound (VOC) emission from the polyvinyl chloride (PVC) wallpaper production industry. In Taiwan, methyl ethyl ketone, TOL, and cyclohexanone have comprised the major content of solvents, accounting for ～113,000 t/yr to avoid excessive viscosity of plasticizer dioctyl phthalate (DOP) and to increase facility in working. Emissions of these VOCs from solvents have caused serious odor and worse air quality problems. In this study, 80 stacks in five factories were tested to evaluate emission characteristics at each VOC source. After examining the VOC concentrations in the flue gases and contents, the VOC emission rate before treatment and from fugitive sources was 93,000 and 800 t/yr, respectively. In this study, the semiwet electrostatic precipitator is recommended for use as cost-effective control equipment.     

Near surface soil vapor clusters for monitoring emissions of volatile organic compounds from soils

The overall objective of this research was to develop and test a method of determining emission rates of volatile organic compounds (VOCs) and other gases from soil surfaces. Soil vapor clusters (SVCs) were designed as a low dead volume, robust sampling system to obtain vertically resolved profiles of soil gas contaminant concentrations in the near surface zone. The concentration profiles, when combined with a mathematical model of porous media mass transport, were used to calculate the contaminant flux from the soil surface. Initial experiments were conducted using a mesoscale soil remediation system under a range of experimental conditions. Helium was used as a tracer and trichloroethene was used as a model VOC. Flux estimations using the SVCs were within 25% of independent surface flux estimates and were comparable to measurements made using a surface isolation flux chamber (SIFC). In addition, method detection limits for the SVC were an order of magnitude lower than detection limits with the SIFC. Field trials, conducted with the SVCs at a bioventing site, indicated that the SVC method could be easily used in the field to estimate fugitive VOC emission rates. Major advantages of the SVC method were its low detection limits, lack of required auxiliary equipment, and ability to obtain real-time estimates of fugitive VOC emission rates.     

Near Surface Soil Vapor Clusters for Monitoring Emissions of Volatile Organic Compounds from Soils

ABSTRACT

The overall objective of this research was to develop and test a method of determining emission rates of volatile organic compounds (VOCs) and other gases from soil surfaces. Soil vapor clusters (SVCs) were designed as a low dead volume, robust sampling system to obtain vertically resolved profiles of soil gas contaminant concentrations in the near surface zone. The concentration profiles, when combined with a mathematical model of porous media mass transport, were used to calculate the contaminant flux from the soil surface. Initial experiments were conducted using a mesoscale soil remediation system under a range of experimental conditions. Helium was used as a tracer and trichloroethene was used as a model VOC. Flux estimations using the SVCs were within 25% of independent surface flux estimates and were comparable to measurements made using a surface isolation flux chamber (SIFC). In addition, method detection limits for the SVC were an order of magnitude lower than detection limits with the SIFC. Field trials, conducted with the SVCs at a bioventing site, indicated that the SVC method could be easily used in the field to estimate fugitive VOC emission rates. Major advantages of the SVC method were its low detection limits, lack of required auxiliary equipment, and ability to obtain realtime estimates of fugitive VOC emission rates.     

Air Levels and Mutagenicity of PM-10 in an Indoor Ice Arena

Abstract

Hazardous waste sites and industrial facilities contain area sources of fugitive emissions. Emission rate measurements or estimates are necessary for air pathway assessments for these sources. Emission rate data can be useful for the design of emission control and remediation strategies as well as for predictive modeling for population exposure assessments. This paper describes the use of a direct emission measurement approach – the enclosure approach using an emission isolation flux chamber – to measure emission rates of various volatile organic compounds (VOCs) from contaminated soil and water. A variety of flux chamber equipment designs and operating procedures have been employed by various researchers. This paper contains a review of the design and operational variables that affect the accuracy and precision of the method. Guidance is given as to the optimum flux chamber design and operating conditions for various types of emission sources. Also presented is a generic quality control program that gives the minimum number of duplicate, blank, background, and repeat samples that should be performed.