烟气催化脱硝装置对多环芳烃排放特性的影响

通过对装有选择性催化还原(SCR)脱硝装置的燃煤锅炉排放烟气中的多环芳烃(PAHs)进行测试,分析比较了工业锅炉排放的PAHs经过SCR脱硝装置前后的排放特性变化.实验结果表明,烟气催化脱硝装置促进了PAHs含量的增加,特别是低环多环芳烃含量的增加,并提高了其毒性当量,但对PAHs在气相与颗粒相的分布影响不大.     

β-环糊精对燃煤焦油和烟气中环芳烃的清除作用

采用三维荧光法测定了7处产地煤样燃烧的焦油和烟气中多环芳烃（PAHs）的含量,焦油中PAHs含量为0.201～0.419 mg/g,烟气中PAHs含量为1.1～3.2 μg/g;测试了β-环糊精（β-CD）溶液对煤烟气中多环芳烃的清除作用,最高去除率可达65.6%。 结果表明：不同产地煤的烟气中PAHs含量不同, 煤焦油中PAHs浓度(mol/L)在10-5数量级,远高于烟气中的浓度(mol/L,10-7数量级)。 用β-CD去除不同产地煤燃烧烟气中多环芳烃的去除率不同。 所选7种煤平均清除率为38.4%。 β-CD溶液有希望成为煤烟气中多环芳烃的清除剂。     

河南贫煤不同温度燃烧烟气中环烃类产物的分析研究

本文用色谱／质谱／红外联用系统研究了河南贫煤在不同温度下燃烧释放的烟气二氯甲烷富集液中的脂环烃，苯系物，多环芳烃及杂多环芳烃等环烃类物的组成和差异，尤其是对多环芳烃的种类，含量及分布特征进行了较详细的探讨。并与原煤常温二氯甲烷浸取中各化合物组成进行了对照。     

荧光法研究香烟烟气中多环芳烃的降低作用

香烟烟气中大约有40多个致肿瘤活性的稠环芳烃[1,2]。人们曾经探索了大量方法[3-6]来降低烟草焦油的致肿瘤活性。环糊精(Cyclodextrin,简称CD)可通过形成包结物[5-8]去除烟气中的多环芳烃。本文对比研究了β-CD溶液对7种不同品牌香烟烟气焦油中多环芳烃的去除率。1实验部分1·1     

飞行时间质谱仪在线检测多环芳烃

采用实验室自行研制飞行时间质谱仪对二(口恶)英常见的关联产物多环芳烃进行了在线检测,选取二环至四环的多环芳烃芴、菲、蒽、萘、芘进行了测量并分析了仪器检测得到的信号.结果表明,该仪器对实验选取的多环芳烃具有良好的响应特性,检测浓度可达到25 nmol/L(即体积浓度500 ppbv),检测结果与实际物质浓度间具有良好的线性关系.使用最小二乘法拟合了浓度和信号强度的线性方程,实现了25～500 nmol/L(体积浓度0.5～10 ppmv)之间检测物质浓度的标定,为进一步发展烟气中的实际多环芳烃测量和浓度标定提供了参考.     

焦炉烟气中全量多环芳烃分析方法

报道了利用处在制串联采样装置。优选出了比较理想的前处理方法，并用此方法对焦炉烟气中的全量多环芳烃进行了研究。滤膜颗粒物中的多环芳烃有６途中 ，聚氨酯泡沫吸附剂中有４９种。     

烟气中多环芳烃吸附脱除的研究

针对热电厂烟气中排放的多环芳烃（PAHs）污染物，在实验室规模上研究了六种吸附剂对烟气中典型的PAHs, 如萘（Nap）、芴（Flu）、菲（Phe）的吸附脱除行为。考察了吸附剂结构特征与Nap，Flu，Phe高温脱除的相关性，并对煤质活性炭（AC-1）在160 ℃～200 ℃下的吸附等温线进行了研究。结果表明，吸附剂对PAHs的吸附能力与其结构参数中BET表面积和微孔体积具有紧密相关性，而与中孔体积没有明显关系；活性炭表现出很好的脱除烟气中PAHs的作用；吸附剂对PAHs的吸附能力随着PAHs的质量分数增大而增大，随吸附温度的增加而减小；随着PAHs的碳原子数和芳环数增加，其在吸附剂上的吸附能力也增强。     

色谱－质谱－红外光谱联用系统研究原煤浸取液及燃煤烟气中环烃类有机污染物

 采用美国惠普公司色谱－质谱－红外三联仪，研究了我国典型煤种──青山烟煤中二氯甲烷（ＣＨ２Ｃｌ２）的４１ｈ浸取液和８００℃燃烧排放烟气中脂环烃、苯系物、多环芳烃（ＰＡＨｓ）等环烃类有机污染物的种类、组成及含量。并用ＰＡＨｓ标样对原煤浸取液和烟气中ＰＡＨｓ排放进行了定量评价。通过两种排放源中各有机污染物的组成和含量比较，获得了原煤及燃后烟气中环烃类有机污染物排放的一般规律。     

色谱－质谱－红外光谱联用系统研究原煤浸取液及燃煤烟气中环烃类有机污染物

采用美国惠普公司色谱－质谱－红外三联仪，研究了我国典型煤种──青山烟煤中二氯甲烷（ＣＨ２Ｃｌ２）的４１ｈ浸取液和８００℃燃烧排放烟气中脂环烃、苯系物、多环芳烃（ＰＡＨｓ）等环烃类有机污染物的种类、组成及含量。并用ＰＡＨｓ标样对原煤浸取液和烟气中ＰＡＨｓ排放进行了定量评价。通过两种排放源中各有机污染物的组成和含量比较，获得了原煤及燃后烟气中环烃类有机污染物排放的一般规律。     

表面增强拉曼光谱结合主成分分析快速筛查食品接触材料中多环芳烃

建立了表面增强拉曼/主成分分析快速筛查食品接触材料中4种多环芳烃的分析方法。采用纳米银溶胶作为增强基底,碘化钾为絮凝剂,实现了4种多环芳烃（芘、荧蒽、苯并［b］荧蒽、苯并［k］荧蒽）的表面增强拉曼分析。针对食品接触材料中4种多环芳烃拉曼谱峰重叠难以鉴别区分的问题,采用主成分分析法分别对同浓度多环芳烃、不同浓度多环芳烃以及多环芳烃混合样品进行分析。结果表明,4种多环芳烃均可得到较好的鉴别。该方法成功用于食品接触材料迁移液中4种多环芳烃的快速筛查。     

On-line monitoring of traces of aromatic-, phenolic- and chlorinated components in flue gases of industrial scale incinerators and cigarette smoke by direct-inlet laser ionization-mass spectrometry (REMPI-TOFMS)

The combination of laser induced resonance-enhanced multiphoton ionization (REMPI) and time-of-flight mass spectrometry (TOFMS) represents a highly selective as well as sensitive analytical technique, well suited for species selective real-time, on-line monitoring of trace-gases. Results presented are obtained with a newly designed, mobile REMPI-TOFMS instrument, optimized for field applications. The mobile REMPI-TOFMS device either is equipped with a compact excimer laser (KrF, λ = 248 nm) or a small Nd:YAG laser (forth harmonic frequency, λ = 266 nm). A special effusive molecular beam inlet system was used, which allows direct inlet of flue gases from e.g. waste incinerators without memory effects for compounds of a molecular weight of up to 260–280 amu. Detection sensitivities in the sub-ppb region are achieved under field measurement conditions. Applications concerning on-line monitoring of combustion byproducts and fuel components are presented. This includes on-line analysis of polycyclic aromatic hydrocarbons (PAH) in the flue gas of a 0.5 MW waste incineration pilot plant, headspace analysis of wood gasification products and crude oil composition (fuel analysis) as well as highly time resolved (single puff resolution) on-line analysis of cigarette smoke. The application of the on-line REMPI-TOFMS monitor for continuous analysis of dioxin indicators in the flue gas of e.g. hazardous waste incinerators is discussed. Received: 25 September 1998 / Revised: 7 December 1998 / Accepted: 10 December 1998     

Quantification of polychlorinated dibenzo-p-dioxins and dibenzofurans by direct injection of sample extract into the comprehensive multidimensional gas chromatograph/high-resolution time-of-flight mass spectrometer

Polychlorinated dibenzo-p-dioxins and dibenzofurans in crude extracts of fly ash and flue gas from municipal waste incinerators were quantified using a comprehensive multidimensional gas chromatograph (GC x GC) coupled to a high-resolution time-of-flight mass spectrometer (HR-TOFMS). For identification and quantification, we developed our own program to prepare 3D chromatograms of selected mass numbers from the data of the GC x GC/HR-TOFMS. Isolation of all congeners with a TCDD toxic equivalency factor from the other isomers by only one injection was confirmed. The instrumental detection limit of TCDD on the GC x GC/HR-TOFMS was 0.9 pg by the relative calibration method. Quantification of these substances in the crude extracts was achieved by direct injection to the GC x GC/HR-TOFMS. The results agree with the values obtained using a generic gas chromatography/high-resolution mass spectrometry (GC/HRMS) system. It was confirmed that measurement by high-resolution TOFMS and GC x GC effectively reduces interference from other chemicals.     

On-line monitoring of traces of aromatic-, phenolic- and chlorinated components in flue gases of industrial scale incinerators and cigarette smoke by direct-inlet laser ionization-mass spectrometry (REMPI-TOFMS)

The combination of laser induced resonance-enhanced multiphoton ionization (REMPI) and time-of-flight mass spectrometry (TOFMS) represents a highly selective as well as sensitive analytical technique, well suited for species selective real-time, on-line monitoring of trace-gases. Results presented are obtained with a newly designed, mobile REMPI-TOFMS instrument, optimized for field applications. The mobile REMPI-TOFMS device either is equipped with a compact excimer laser (KrF, λ = 248 nm) or a small Nd:YAG laser (forth harmonic frequency, λ = 266 nm). A special effusive molecular beam inlet system was used, which allows direct inlet of flue gases from e.g. waste incinerators without memory effects for compounds of a molecular weight of up to 260–280 amu. Detection sensitivities in the sub-ppb region are achieved under field measurement conditions. Applications concerning on-line monitoring of combustion byproducts and fuel components are presented. This includes on-line analysis of polycyclic aromatic hydrocarbons (PAH) in the flue gas of a 0.5 MW waste incineration pilot plant, headspace analysis of wood gasification products and crude oil composition (fuel analysis) as well as highly time resolved (single puff resolution) on-line analysis of cigarette smoke. The application of the on-line REMPI-TOFMS monitor for continuous analysis of dioxin indicators in the flue gas of e.g. hazardous waste incinerators is discussed.     

废弃物燃烧产生的可吸入颗粒物中金属元素的排放特性研究

将纸屑、甘蔗渣、木粉、谷壳、垃圾衍生燃料（RDF）五种废弃物进行燃烧，采集其烟气中可吸入颗粒物（PM10）样品并分析，获得了颗粒物中金属元素的质量分数和排放特性，并与其相应的原料和灰烬中的金属元素质量分数比较。结果显示，废弃物燃烧的颗粒物中金属元素的种类与燃烧的物料有关；纸屑的颗粒物中金属元素的质量分数最低，RDF的最高，其余三种生物质废弃物的质量分数较相近；在五种样品中，一些重金属的质量分数很高，比土壤中的质量分数高出很多倍；金属元素在灰烬和颗粒物中的分布情况与金属元素的性质密切相关，且在可吸入颗粒物上有明显的富集。     

Long-term monitoring of PCDD/PCDF and other unintentionally produced POPs — Concepts and case studies from Europe

During the start-up and unstable combustion periods, even the state-of-the-art incinerators emit polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) in stack gases at concentrations that are up to 1000 times higher than normal operation. Therefore, incinerators and other sources with variation of PCDD/PCDF release into air cannot be reliably monitored by the conventional short-term sampling that covers only 0.1% to 0.2% of the yearly operating time. A more comprehensive monitoring regime is required. This paper describes different applications of continuous PCDD/PCDF sampling in some European countries. The cases demonstrate that flexible regimes for continuous sampling can be crafted and applied by governments or regional/local authorities. Such regimes range from a countrywide, continuous requirement for selected facility types (e.g., waste incinerators) to a facility-specific regime that applies, for example, to new facilities for a defined time period until the facility has demonstrated continuous compliance with regulatory limits. Countries implementing the Stockholm Convention are suggested to evaluate in their Best available technology/Best environmental practice (BAT/BEP) activities the usefulness of long-term sampling by, for example, designating institutes related to the environmental ministry or regional authorities to supervise long-term sampling regimes at relevant facilities in their country/areas, beginning with priority sources (e.g., facilities used for destruction of persistent organic pollutants (POPs) or hazardous waste processing). This paper presents and discusses the results of the AMESA long-term monitoring system having demonstrated that in addition to PCDD/PCDF all other unintentionally produced POPs listed in the Stockholm Convention could be supervised.     

Partitionings and kinetic behaviors of major-to-ultratrace elements between industrial waste incineration fly and bottom ashes as studied by ICP-AES and ICP-MS.

The partitionings of major-to-ultratrace elements between industrial waste incineration fly ash (IWIFA) and industrial waste incineration bottom ash (IWIBA) in industrial waste incinerators were investigated by measuring their concentration distributions, where the incineration ash samples were collected from three different types of industrial waste incinerators. The concentrations of the elements in the incineration ash samples were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). As a result, ca. 40 elements in the concentration range from mg g(-1) to sub-microg g(-1) could be determined in both IWIFA and IWIBA samples. The concentration ratios of CF/CB (CF, concentration in fly ash; CB, concentration in bottom ash) for analyte elements were used to evaluate the partitionings of the elements between fly and bottom ashes. Then, the correlations between the CF/CB values of the elements and the dissociation energies of their monoxides were examined to evaluate the kinetic behaviors of the elements during the incineration processes. It was found that lithophile and siderophile elements, which have a large affinity with oxygen, were almost equally distributed between fly and bottom ashes, regardless of the dissociation energies of their monoxides. On the other hand, chalcophile elements with rather large volatility provided different behaviors; the elements with the smaller dissociation energies of monoxides were more partitioned in fly ashes than those with the larger ones.     

Analysis of polycyclic aromatic compounds in the fly ash of an incineration plant for radioactive waste

Organic compounds adsorbed on fly ash from an incinerator for radioactive waste were investigated. Following Soxhlet extraction and concentration, analysis was performed by GC and GC/MS using high temperature silylated glass capillary columns coated with OV-1 and SE-54. Compound identification was based on retention data, relative detector responses, and mass spectra. Among other polycyclic aromatic compounds, series of gradually chlorinated PAHs containing four to seven aromatic rings were detected. For unequivocal identification, appropriate reference compounds were synthesized by chlorination of the corresponding parent PAHs.     

Optimisation of supercritical fluid extraction of polynuclear aromatic hydrocarbons from spiked soil and marine sediment standard reference material

 For the determination of 16 PAHs in soils and sediment samples by GC/FID and GC/MS, the dynamic off-line supercritical fluid extraction with both pure and modified carbon dioxide has been evaluated. The optimisation of extraction parameters was performed for four individual groups of PAHs according to their number of aromatic rings (2–3 rings, 4 rings, 5 rings and 6 rings) by varying pressure (200–510 bar), temperature (50–150 °C), extraction fluid volume (10–50 ml), and the methanol modifier concentration (0–10%). Using a five level spherical factorial experimental design the number of experiments required for optimisation was 45. In spiked soil samples extraction efficiencies of 80–100% were achieved for the individual groups of PAHs. At the optimal set of conditions 10–30% lower recoveries of PAHs were obtained for the standard reference material NIST SRM 1941a (marine sediment). The largest differences between extraction recoveries of native and spiked PAHs occurred at high molecular weight PAHs. Using SFE efficiency data for the standard reference material, cluster analysis proved that dividing the 16 PAHs into four groups according to their number of aromatic rings was appropriate and correct. Received: 2 February 1996/Revised: 26 November 1996/Accepted: 30 November 1996     

Calibration of the complex matrix effects on the sampling of polycyclic aromatic hydrocarbons in milk samples using solid phase microextraction

Solid phase microextraction (SPME), a simple, fast and promising sampling technique, has been widely used for complex sample analysis. However, complex matrices could modify the absorption property of coatings as well as the uptake kinetics of analytes, eventually biasing the quantification results. In the current study, we demonstrated the feasibility of a developed calibration method for the analysis of polycyclic aromatic hydrocarbons (PAHs) in complex milk samples. Effects of the complex matrices on the SPME sampling process and the sampling conditions were investigated. Results showed that short exposure time (pre-equilibrium SPME, PE-SPME) could increase the lifetime of coatings, and the complex matrices in milk samples could significantly influence the sampling kinetics of SPME. In addition, the optimized sampling time, temperature and dilution factor for PAHs were 10 min, 85 °C and 20, respectively. The obtained LODs and LOQs of all the PAHs were 0.1–0.8 ng/mL and 1.4–4.7 ng/mL, respectively. Furthermore, the accuracy of the proposed PE-SPME method for milk sampling was validated by the recoveries of the studied compounds in two concentration levels, which ranged from 75% to 110% for all the compounds. Finally, the proposed method was applied to the screening of PAHs in milk samples.