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1.
石化工业区周边土壤中多环芳烃的组成及分布特征分析 总被引:1,自引:0,他引:1
《环境污染与防治》2015,(8)
采集某石化工业区周边20个表层土壤样品,分析了其中16种优控多环芳烃(PAHs)的含量与分布特征,并对其污染水平及来源进行了解析。结果表明,各采样点土样中16种PAHs的总质量浓度在268.16~3 304.60μg/kg,平均为1 032.24μg/kg,除芴、苊外,其余14种PAHs在各采样点土样中均有不同程度的检出,该研究区周边土壤已经普遍受到PAHs的影响,且污染程度主要集中在中重度污染;总的来看,各采样点PAHs的组成结构规律基本一致,所占比例以4环为主,5~6环居中,2~3环较低;根据PAHs特征比值法判断,该石化工业区周边土壤中PAHs污染主要来源于煤等生物质的高温燃烧,小部分地区受到石油燃烧源输入的影响,而机动车尾气排放也可能是PAHs的来源之一。 相似文献
2.
为分析峰峰矿区煤矿开采后矿区地下水多环芳烃(PAHs)的分布和来源,在矿区采集并分析了15件奥灰水样品,对样品中16种PAHs的含量进行统计分析,并运用氢氧同位素和同分异构体比值相结合的方法分析确定了其污染来源。结果表明:峰峰矿区奥灰水中PAHs总质量浓度为0.06~0.56ng/L,呈现出萘(Nap)、菲(Phe)、蒽(Ant)、荧蒽(Flt)、芘(Pyr)、芴(Flu)为主的2~4环PAHs低浓度高检出特征;Ant/(Ant+Phe)—Flt/(Flt+Pyr)结果表明奥灰水中PAHs主要来自煤和生物质的燃烧;δD—δ18 O、δD—Phe结果表明,奥灰水中的PAHs主要来源于煤和生物质燃烧产物在高海拔基岩裸露地区随降雨直接入渗补给;少数来源于潜水、矿井水和煤系基岩水等的越流补给。 相似文献
3.
福州市蔬菜基地土壤重金属和多环芳烃的含量及其与土壤磁性指标的关系 总被引:1,自引:0,他引:1
蔬菜基地土壤污染状况与人类健康有着密切的关系。本研究对福州市蔬菜基地土壤中6种重金属和15种美国环境保护总署(US EPA)优控的多环芳烃(PAHs)污染状况进行了调查,并分析了污染物含量与土壤磁性指标间的关系。结果表明,土壤中重金属平均含量为Zn 147.0 mg·kg-1、Pb 55.0 mg·kg-1、Cu 45.5 mg·kg-1、Cr 21.3 mg·kg-1、As 16.0 mg·kg-1、Cd 0.6 mg·kg-1;PAHs的总量范围为324.3~1 838.6 μg·kg-1。Cu含量和PAHs总量与土壤磁化率χ都具有显著的相关性(pχfd的结果分析表明,土壤中PAHs主要来源于石油泄漏和生物质的燃烧;重金属来源复杂,为混合来源,包括人类活动排放和成土母质固有含量。污染评价结果表明,土壤中Cr和As的含量都未超标,Cu、Zn和Cd的含量均超标;参考荷兰土壤修复标准中的目标值, PAHs含量超标的土壤为11.1%,而参照我国土壤污染状况评价技术规定,PAHs含量超标的土壤为22.2%。 相似文献
4.
2012年3-8月对北京西三环地区大气颗粒物进行分级采样,利用气相色谱(GC)/质谱(MS)联用仪对颗粒物中多环芳烃(PAHs)含量进行测定.结果表明,检出的16种PAHs总质量浓度(∑16PAHs)平均为46.73ng/m3;苯并[a]蒽(BaA)等6种单体浓度与∑16PAHs呈良好线性关系;PAHs粒径分布特征表明,其更易富集在细颗粒物上;不同环数PAHs分布特征为:3环>4环>5环>6环>2环,随着颗粒粒径减小,高环数PAHs含量增加.温度、湿度和紫外线(UV)指数与∑16PAHs呈负相关.通过特征化合物比值分析法对PAHs进行源解析发现,采样期间PAHs主要来源为燃烧源,交通源影响微弱. 相似文献
5.
利用PUF被动采样器于2008年8月—2009年7月采集了西安大气样品,研究了大气气相中多环芳烃(PAHs)的含量和季节分布特征。结果表明,西安大气气相中16种美国EPA优控的PAHs(Σ16PAHs)质量浓度为10.9-489.6 ng/m3(平均为143.4 ng/m3),四季具有明显的季节差异,依次为夏季(62.5 ng/m3)〈春季(80.1 ng/m3)〈秋季(175.8 ng/m3)〈冬季(255.2 ng/m3)。气相中PAHs主要以3-4环为主,占总量的86.5%-94.1%。利用主成分分析法判断四季气相中PAHs的污染来源类型,主要为燃煤和机动车尾气及生物质燃烧的复合源。 相似文献
6.
苏州河上海市区段表层沉积物中多环芳烃的分布及特征 总被引:3,自引:0,他引:3
参照美国EPA8000系列方法、质量保证和质量控制,对苏州河上海市区段的表层沉积物中16种优控多环芳烃类有机物(PAHs)进行了分析.结果表明,苏州河上海市区段的表层沉积物均受到了很大程度的污染,其中处于市区中段的昌化路桥、西康路桥和长寿路桥断面的PAHs含量较高,处于黄浦江入口附近的四川路桥、河南路桥和福建路桥断面的含量较低.同时发现,近十几年来苏州河沉积物中的PAHs含量和成分发生了一定的变化,对其原因作了初步探讨. 相似文献
7.
《环境污染与防治》2015,(11)
通过采集鞍山市城市PM_(2.5)样品,使用气相色谱—质谱联用仪分析PM_(2.5)样品中的多环芳烃(PAHs)含量,并进行PAHs组成特征及来源研究。结果表明,鞍山市6个采样点13种PAHs质量浓度总和为10.54~14.26ng/m3,平均为12.08ng/m3,苯并[a]芘日均浓度均未超过《环境空气质量标准》(GB 3095—2012)日均浓度限值;低分子量PAHs比例较低,5、6环PAHs呈相对优势分布,表明交通污染源对鞍山市PM_(2.5)中的PAHs贡献较大;利用比值法和主成分分析(PCA)法对PAHs来源进行解析,两种方法均表明,PAHs污染主要来自柴油、煤炭燃烧源和焦炉源,污染类型为煤烟和交通复合型。 相似文献
8.
为了解西安市7月大气降尘中多环芳烃(PAHs)的污染特征,在对西安市各功能区7月大气降尘样品采集的基础上,测定分析了样品中PAHs的含量、组成、来源、生态健康风险及其与总有机碳(TOC)的关系。结果表明:(1)西安市7月大气降尘中PAHs为0.92~20.60μg/g,平均值为8.10μg/g,其中荧蒽、菲、芘、和苯并[a]芘含量相对较大。各功能区大气降尘中PAHs主要以4环为主。(2)PAHs与TOC之间存在显著相关性,而各单体PAHs与TOC呈现不同程度的相关性。(3)西安市7月大气降尘中PAHs主要来源于机动车排放、燃煤和低温燃烧。(4)依据终生癌症风险增量(ILCR)模型,大气降尘中PAHs对不同暴露人群的风险值均为10~(-6)~10~(-4),存在人体可耐受致癌风险。生态风险评价显示,大气降尘中PAHs污染存在潜在生态风险。 相似文献
9.
杭州市冬春季大气细颗粒物中多环芳烃的粒径分布特征及细胞毒性研究 总被引:1,自引:0,他引:1
《环境污染与防治》2017,(2)
为了解杭州市大气细颗粒物中多环芳烃(PAHs)的粒径分布特征和主要来源,于2015年12月至2016年5月在杭州市某商住区采集了不同粒径的大气细颗粒物样品,利用气相色谱质谱联用仪对其中的PAHs进行分析,并进行了细胞毒性试验。结果表明,不同粒径大气细颗粒物中PAHs的总浓度冬季均明显高于春季。冬春两季的PAHs环数粒径分布基本呈现出4环5环3环6环2环。通过特征比值法判定,杭州市大气细颗粒物中的PAHs主要来源于燃烧源和机动车尾气排放。细胞毒性试验结果表明,粒径越小的大气细颗粒物对细胞的毒性作用越强,对细胞膜损伤程度越大。 相似文献
10.
为了解焦化厂在装煤过程中产生的PM2.5及其周边区域空气环境PM2.5中多环芳烃(PAHs)的含量,采用微纤维石英滤膜对PM2.5采样,并通过气相色谱-质谱仪分析PM2.5上负载的16种毒性较大PAHs。结果表明:焦炉装煤除尘烟气PM2.5中PAHs的成分主要受到炼焦配煤的影响;布袋除尘器对装煤除尘烟气中高环PAHs的处理效果显著;焦化厂周边空气环境中PM2.5中的PAHs浓度呈明显空间递减趋势。采用特征比值法分析得到该区域空气环境中PAHs主要来源于煤炭燃烧,用毒性当量法分析得到焦化厂区域PM2.5中PAHs的毒性为其他区域的9~90倍,高环PAHs的毒性贡献较大。 相似文献
11.
Esther Borrás Luis A. Tortajada-Genaro Monica Vázquez Barbara Zielinska 《Atmospheric environment (Oxford, England : 1994)》2009,43(37):5944-5952
The study of light-duty diesel engine exhaust emissions is important due to their impact on atmospheric chemistry and air pollution. In this study, both the gas and the particulate phase of fuel exhaust were analyzed to investigate the effects of diesel reformulation and engine operating parameters. The research was focused on polycyclic aromatic hydrocarbon (PAH) compounds on particulate phase due to their high toxicity. These were analyzed using a gas chromatography–mass spectrometry (GC–MS) methodology.Although PAH profiles changed for diesel fuels with low-sulfur content and different percentages of aromatic hydrocarbons (5–25%), no significant differences for total PAH concentrations were detected. However, rape oil methyl ester biodiesel showed a greater number of PAH compounds, but in lower concentrations (close to 50%) than the reformulated diesel fuels. In addition, four engine operating conditions were evaluated, and the results showed that, during cold start, higher concentrations were observed for high molecular weight PAHs than during idling cycle and that the acceleration cycles provided higher concentrations than the steady-state conditions. Correlations between particulate PAHs and gas phase products were also observed.The emission of PAH compounds from the incomplete combustion of diesel fuel depended greatly on the source of the fuel and the driving patterns. 相似文献
12.
Diesel fuels governed by U.S. regulations are based on the index of the total aromatic contents. Three diesel fuels, containing various fractions of light cycle oil (LCO) and various sulfur, total polyaromatic, and total aromatic contents, were used in a heavy-duty diesel engine (HDDE) under transient cycle test to assess the feasibility of using current indices in managing the emissions of polycyclic aromatic hydrocarbons (PAHs) from HDDE. The mean sulfur content in LCO is 20.8 times as much as that of premium diesel fuel (PDF). The mean total polyaromatic content in LCO is 28.7 times as much as that of PDF, and the mean total aromatic content in LCO is 2.53 times as much as that of PDF. The total polyaromatic hydrocarbon emission factors in the exhaust from the diesel engine, as determined using PDF L3.5 (3.5% LCO and 96.5% PDF), L7.5 (7.5% LCO and 92.5% PDF), and L15 (15% LCO and 85% PDF) were 14.3, 25.8, 44, and 101 mg L(-1), respectively. The total benzo(a)pyrene equivalent (BaPeq) emission factors in the exhaust from PDF, L3.5, L7.5, and L15 were 0.0402, 0.121, 0.219, and 0.548 mg L(-1), respectively. Results indicated that using L3.5 instead of PDF will result in an 80.4% and a 201% increase of emission for total PAHs and total BaPeq, respectively. The relationships between the total polyaromatic hydrocarbon emission factor and the two emission control indices, including fuel polyaromatic content and fuel aromatic content, suggest that both indices could be used feasibly to regulate total PAH emissions. These results strongly suggest that LCO used in the traveling diesel vehicles significantly influences PAH emissions. 相似文献
13.
Zhu J Cao XL Pigeon R Mitchell K 《Journal of the Air & Waste Management Association (1995)》2003,53(1):67-76
Three diesel fuels, one oil sand-derived (OSD) diesel serving as base fuel, one cetane-enhanced base fuel, and one oxygenate [diethylene glycol dimethyl ether (DEDM)]-blended base fuel, were tested for their emission characterizations in vehicle exhaust on a light-duty diesel truck that reflects the engine technology of the 1994 North American standard. Both the cetane-enhanced and the oxygenate-blended fuels were able to reduce regulated [CO, particulate matter (PM), total hydrocarbon (THC)] and nonregulated [polyaromatic hydrocarbons (PAHs), carbonyls, and other volatile organic chemicals] emissions, except for nitrogen oxides (NO(x)), compared with the base fuel. Although burning a fuel that contains oxygen could conceivably yield more oxygenated compounds in emissions, the oxygenate-blended diesel fuel resulted in reduced emissions of formaldehyde along with hydrocarbons such as benzene, 1,3-butadiene, and PAHs. Reductions in nitro-PAH emissions have been observed in both the cetane-enhanced and oxygenated fuels. This further demonstrates the benefits of using a cetane enhancer and the oxygenated fuel component. 相似文献
14.
Yuan-Chung Lin Wen-Jhy Lee Chung-Bang Chen 《Journal of the Air & Waste Management Association (1995)》2013,63(6):752-758
Abstract Diesel fuels governed by U.S. regulations are based on the index of the total aromatic contents. Three diesel fuels, containing various fractions of light cycle oil (LCO) and various sulfur, total polyaromatic, and total aromatic contents, were used in a heavy-duty diesel engine (HDDE) under transient cycle test to assess the feasibility of using current indices in managing the emissions of polycyclic aromatic hydrocarbons (PAHs) from HDDE. The mean sulfur content in LCO is 20.8 times as much as that of premium diesel fuel (PDF). The mean total polyaromatic content in LCO is 28.7 times as much as that of PDF, and the mean total aromatic content in LCO is 2.53 times as much as that of PDF. The total polyaromatic hydrocarbon emission factors in the exhaust from the diesel engine, as determined using PDF L3.5 (3.5% LCO and 96.5% PDF), L7.5 (7.5% LCO and 92.5% PDF), and L15 (15% LCO and 85% PDF) were 14.3, 25.8, 44, and 101 mg L?1, respectively. The total benzo(a)pyrene equivalent (BaPeq) emission factors in the exhaust from PDF, L3.5, L7.5, and L15 were 0.0402, 0.121, 0.219, and 0.548 mg L?1, respectively. Results indicated that using L3.5 instead of PDF will result in an 80.4% and a 201% increase of emission for total PAHs and total BaPeq, respectively. The relationships between the total polyaromatic hydrocarbon emission factor and the two emission control indices, including fuel polyaromatic content and fuel aromatic content, suggest that both indices could be used feasibly to regulate total PAH emissions. These results strongly suggest that LCO used in the traveling diesel vehicles significantly influences PAH emissions. 相似文献
15.
Fu F Tian B Lin G Chen Y Zhang J 《Journal of the Air & Waste Management Association (1995)》2010,60(11):1309-1314
To obtain the characteristic factors or signatures of particulate polycyclic aromatic hydrocarbons (PAHs) to help identify the sources of particulate PAHs in the atmosphere, different carbonaceous aerosols were generated by burning different fossil fuels and biomass under different conditions in the laboratory, and the chemical characteristics of 14 PAHs were studied in detail. The results showed that (1) carbonaceous aerosols derived from domestic burning of coal, diesel fuel, and gasoline have much higher concentrations of PAHs than those derived from domestic burning of biomass; (2) carbonaceous aerosols derived from domestic burning of diesel fuel/gasoline have similar PAH components as those derived from high-temperature combustion of diesel fuel/gasoline, although the former have much higher concentrations of PAHs than the latter, suggesting that the burning temperature obviously affects the emitting amount of particulate PAHs, but only slightly influences the PAHs components; and (3) the ratios of benzo[b]fluoranthene/acenaphthylene, benzo[b]fluoranthene/fluorene, dibenzo[a,h]anthracene/acenaphthylene, dibenzo[a,h]anthracene/fluorine, and benzo[b]fluoranthene/benzo[k]fluoranthene in carbonaceous aerosols are sensitively dependent on their sources, indicating that these ratios are suitable for use as characteristic factors or signatures of particulate PAHs in the atmosphere. 相似文献
16.
《Atmospheric environment (Oxford, England : 1994)》2007,41(16):3373-3380
The use of biodiesel fuel as a substitute for fossil fuel in diesel engines has received increasing attention in recent years. This study is the first to investigate and compare the characteristics of mutagenic species, trans,trans-2,4-decadienal (tt-DDE), and polycyclic aromatic hydrocarbons (PAHs) in the diluted exhaust of diesel engines operated with diesel and biodiesel blend fuels. An engine of current design was operated on a dynamometer consistent with the US federal test procedure transient-cycle specifications. Petroleum diesel and a blend of petroleum diesel and biodiesel (B20) were tested. Exhaust sampling was carried out on diluted exhaust in a dilution tunnel with a constant-volume sampling system. Concentrations of tt-DDE and PAHs were analyzed by GC/MS. Although average PAH emission factors decreased from 1403 to 1051 μg bhp-h−1, the results show that tt-DDE is evidently generated (1.28 μg bhp-h−1) in the exhaust of diesel engine using B20 as fuel. This finding suggests that tt-DDE emission from the use of biodiesel should be taken into account in characterization and health-risk assessment. The results also show that tt-DDE is depleted in the diesel engine combustion process and the existence of tt-DDE in biodiesel is the major source of tt-DDE emission. The distribution of tt-DDE in the particulate phase is 55.3% under this study's sampling conditions. For diesel and B20, PAH phase distributions have similar trends. Lower molecular weight PAHs predominate in gaseous phase for both diesel and B20. Cold-start driving has higher tt-DDE and PAH emission factors, as well as a higher percentage of tt-DDE in particulate phase, than for warm-start driving. 相似文献
17.
Fujita EM Zielinska B Campbell DE Arnott WP Sagebiel JC Mazzoleni L Chow JC Gabele PA Crews W Snow R Clark NN Wayne WS Lawson DR 《Journal of the Air & Waste Management Association (1995)》2007,57(6):705-720
The U.S. Department of Energy Gasoline/Diesel PM Split Study examined the sources of uncertainties in using an organic compound-based chemical mass balance receptor model to quantify the contributions of spark-ignition (SI) and compression-ignition (CI) engine exhaust to ambient fine particulate matter (PM2.5). This paper presents the chemical composition profiles of SI and CI engine exhaust from the vehicle-testing portion of the study. Chemical analysis of source samples consisted of gravimetric mass, elements, ions, organic carbon (OC), and elemental carbon (EC) by the Interagency Monitoring of Protected Visual Environments (IMPROVE) and Speciation Trends Network (STN) thermal/optical methods, polycyclic aromatic hydrocarbons (PAHs), hopanes, steranes, alkanes, and polar organic compounds. More than half of the mass of carbonaceous particles emitted by heavy-duty diesel trucks was EC (IMPROVE) and emissions from SI vehicles contained predominantly OC. Although total carbon (TC) by the IMPROVE and STN protocols agreed well for all of the samples, the STN/IMPROVE ratios for EC from SI exhaust decreased with decreasing sample loading. SI vehicles, whether low or high emitters, emitted greater amounts of high-molecular-weight particulate PAHs (benzo[ghi]perylene, indeno[1,2,3-cd]pyrene, and coronene) than did CI vehicles. Diesel emissions contained higher abundances of two- to four-ring semivolatile PAHs. Diacids were emitted by CI vehicles but are also prevalent in secondary organic aerosols, so they cannot be considered unique tracers. Hopanes and steranes were present in lubricating oil with similar composition for both gasoline and diesel vehicles and were negligible in gasoline or diesel fuels. CI vehicles emitted greater total amounts of hopanes and steranes on a mass per mile basis, but abundances were comparable to SI exhaust normalized to TC emissions within measurement uncertainty. The combustion-produced high-molecular-weight PAHs were found in used gasoline motor oil but not in fresh oil and are negligible in used diesel engine oil. The contributions of lubrication oils to abundances of these PAHs in the exhaust were large in some cases and were variable with the age and consumption rate of the oil. These factors contributed to the observed variations in their abundances to total carbon or PM2.5 among the SI composition profiles. 相似文献
18.
Semi-volatile and particulate emissions from the combustion of alternative diesel fuels 总被引:8,自引:0,他引:8
Motor vehicle emissions are a major anthropogenic source of air pollution and contribute to the deterioration of urban air quality. In this paper, we report results of a laboratory investigation of particle formation from four different alternative diesel fuels, namely, compressed natural gas (CNG), dimethyl ether (DME), biodiesel, and diesel, under fuel-rich conditions in the temperature range of 800-1200 degrees C at pressures of approximately 24 atm. A single pulse shock tube was used to simulate compression ignition (CI) combustion conditions. Gaseous fuels (CNG and DME) were exposed premixed in air while liquid fuels (diesel and biodiesel) were injected using a high-pressure liquid injector. The results of surface analysis using a scanning electron microscope showed that the particles formed from combustion of all four of the above-mentioned fuels had a mean diameter less than 0.1 microm. From results of gravimetric analysis and fuel injection size it was found that under the test conditions described above the relative particulate yields from CNG, DME, biodiesel, and diesel were 0.30%. 0.026%, 0.52%, and 0.51%, respectively. Chemical analysis of particles showed that DME combustion particles had the highest soluble organic fraction (SOF) at 71%, followed by biodiesel (66%), CNG (38%) and diesel (20%). This illustrates that in case of both gaseous and liquid fuels, oxygenated fuels have a higher SOF than non-oxygenated fuels. 相似文献
19.
Yuan CS Lin HY Lee WJ Lin YC Wu TS Chen KF 《Journal of the Air & Waste Management Association (1995)》2007,57(4):465-471
This study investigated the emissions of polycyclic aromatic hydrocarbons (PAHs), carcinogenic potential of PAH and particulate matter (PM), brake-specific fuel consumption (BSFC), and power from diesel engines under transient cycle testing of six test fuels: premium diesel fuel (PDF), B100 (100% palm biodiesel), B20 (20% palm biodiesel + 80% PDF), BP9505 (95% paraffinic fuel + 5% palm biodiesel), BP8020 (80% paraffinic fuel + 20% palm biodiesel), and BP100 (100% paraffinic fuel; Table 1). Experimental results indicated that B100, BP9505, BP8020, and BP100 were much safer when stored than PDF. However, we must use additives so that B100 and BP100 will not gel as quickly in a cold zone. Using B100, BP9505, and BP8020 instead of PDF reduced PM, THC, and CO emissions dramatically but increased CO2 slightly because of more complete combustion. The CO2-increased fraction of BP9505 was the lowest among test blends. Furthermore, using B100, B20, BP9505, and BP8020 as alternative fuels reduced total PAHs and total benzo[a]pyrene equivalent concentration (total BaPeq) emissions significantly. BP9505 had the lowest decreased fractions of power and torque and increased fraction of BSFC. These experimental results implied that BP9505 is feasible for traveling diesel vehicles. Moreover, paraffinic fuel will likely be a new alternative fuel in the future. Using BP9505 instead of PDF decreased PM (22.8%), THC (13.4%), CO (25.3%), total PAHs (88.9%), and total BaPeq (88.1%) emissions significantly. 相似文献
20.
Size distribution of polycyclic aromatic hydrocarbons in urban and suburban sites of Beijing, China 总被引:9,自引:0,他引:9
PAHs in five-stage size segregated aerosol particles were investigated in 2003 at urban and suburban sites of Beijing. The total concentration of 17 PAHs ranged between 0.84 and 152 ng m(-3), with an average of 116 ng m(-3), in urban area were 1.1-6.6 times higher than those measured in suburban area. It suggested a serious pollution level of PAHs in Beijing. PAHs concentrations increased with decreasing the ambient temperature. Approximately 68.4-84.7% of PAHs were adsorbed on particles having aerodynamic diameter 2.0 microm. Nearly bimodal distribution was found for PAHs with two and three rings, more than four rings PAHs, however, followed unimodal distribution. The overall mass median diameter (MMD) for PAHs decreased with increasing molecular weight. Diagnostic ratios and normalized distribution of PAHs indicated that the PAHs in aerosol particles were mainly derived from fossil fuel combustion. Coal combustion for domestic heating was probably major contributor to the higher PAHs loading in winter, whereas PAHs in other seasons displayed characteristic of mixed source of gasoline and diesel vehicle exhaust. Biomass burning and road dust are minor contributors to the PAHs composition of these aerosol particles. Except for source emission, other factors, such as meteorological condition, photochemical decay, and transportation from source to the receptor site, should to be involved in the generation of the observed patterns. 相似文献