市政垃圾焚烧飞灰中添加CaO抑制PCDD/Fs生成试验探究

采用自制装置,以CaO作为PCDD/Fs生成抑制剂,对市政垃圾焚烧飞灰做热处理。通过试验考察温度、CaO添加量等因素对飞灰中PCDD/Fs生成的影响。结果表明：质量分数为5%的CaO添加可以减少80%的PCDD/Fs生成。     

某典型生活垃圾焚烧企业烟气中二噁英类变化特征

本文选取了1家典型的生活垃圾焚烧企业作为研究对象,分别采集了净化前和净化后的烟气,结果表明:净化后的烟气中二噁英毒性当量浓度均低于0.1 ng TEQ/Nm 3,去除效率为98.3%;净化前二噁英主要以“从头合成”为主,净化后变化成“前驱物合成”为主;无论是烟气净化前还是净化后,O 8CDD、1,2,3,4,6,7,8-H 7CDD和1,2,3,4,6,7,8-H 7CDF,占比都是最大的;通过相关性分析,1,2,3,4,7,8-H 6CDF质量浓度与I-TEQ相关性最高,可作为二噁英潜在的测定指示物。通过对比研究净化前后的烟气,初步掌握了二噁英工艺流程中变化特征,为企业焚烧控制技术和环境管理提供了数据支持。     

生活垃圾焚烧二噁英排放对人群健康影响研究进展

综述了二噁英对人体健康的危害特性, 以及我国生活垃圾焚烧厂二噁英排放浓度水平,及其周边环境空气和土壤中二噁英污染浓度水平、人群暴露途径、剂量和健康影响。指出,现有研究显示,我国生活垃圾焚烧排放的二噁英浓度在合理范围之内,垃圾焚烧厂周边人群二噁英暴露量普遍低于世界卫生组织（WHO）推荐的容许标准,但也有研究发现,垃圾焚烧会导致周边环境介质中二噁英浓度水平增高。提出,应重点关注垃圾焚烧排放二噁英的长期低剂量暴露对人群健康的影响。     

生活垃圾焚烧飞灰重金属检测试验方法探讨

生活垃圾焚烧飞灰中由于含有大量重金属等污染物而被列为危险废物,常见的重金属检测方法包括形态分析、全量测试及浸出毒性评价。本文对国内外这3类检测方法进行了系统总结及对比,选择出适合我国垃圾焚烧飞灰的重金属检测方法或标准,为飞灰的无害化资源化处置利用提供参考。     

M12半自动净化法与手工净化法应用于飞灰中二噁英类检测比较

研究比较了M12半自动净化法与手工净化法应用于二噁英检测的效果。结果显示,采用高分辨气相色谱-高分辨质谱法(HRGC-HRMS)检测飞灰样品中的二噁英,手工净化法的回收率要优于M12半自动净化法的回收率,但M12半自动净化法除2种单体外,其余单体回收率均满足对二噁英的分析要求,且2种净化方法所得二噁英的总毒性当量结果相近,证明手工净化法与HRGC-HRMS联用检测飞灰中二噁英的效果较好,但M12半自动净化法也能够满足HRGC-HRMS检测二噁英的净化要求。应用酶联免疫法检测飞灰样品中二噁英的总毒性量,当样品中二噁英浓度较高时,M12半自动净化法和手工净化法净化测得结果与基准值一致性较好;当样品中二噁英浓度较低时,手工净化法检测结果与基准值差别较大,表明酶联免疫法更适合用M12半自动净化法进行净化。     

生活垃圾与危险废物焚烧二噁英类排放特征研究

对某省52家焚烧企业(21家生活垃圾和31家危险废物)排放烟气数据进行了分析,结果表明,两类焚烧企业二噁英类17种单体分布有所不同,生活垃圾焚烧烟气中浓度较高的是O8CDD和O8CDF;危险废物焚烧烟气中较大的是2,3,4,7,8-P5CDF、2,3,7,8-T4CDD和1,2,3,7,8-P5CDD;两类焚烧企业二噁英类单体对I-TEQ贡献最高的都是2,3,4,7,8-P5CDF,贡献率分别为0. 7%～45%和10%～67%;两者的17种二噁英类与I-TEQ的相关性分析表明,1,2,3,7,8-P5CDF在2类焚烧炉中与I-TEQ均存在较高的相关性,其相关系数分别0. 932和0. 927,可以作为潜在的测定指示物。     

生活垃圾焚烧炉烟气中二噁英排放水平及控制措施

对浙江省14家企业32台生活垃圾焚烧炉开展验收监测,结果表明,其烟气二噁英的排放值均能达到现行标准的限值要求(0.013 ng TEQ/m~3~0.100 ng TEQ/m~3,平均值为0.059 ng TEQ/m~3),焚烧每吨生活垃圾二噁英的排放量为248.1 ng。分析了二噁英的主要生成途径与控制措施,提出了做好垃圾分类与预处理,加强人员培训,运营管理公开、透明、规范化等进一步降低二噁英排放水平的建议。     

二噁英类等环境激素污染物的来源监测调查

二英类对环境的污染及对内分泌的干扰作用已引起世界各国的广泛关注。本文叙述了水中二英类的来源 ,在食物链中的迁移、生物富集、生物放大及日本环境空气、土壤、水、底质及生物 ,食品中二英类的存在情况。还报道了世界各国二英类发生源及大致排放量。本文还介绍了目前在国外通用的二英等环境激素类物质的监测分析方法及我国制定此类监测分析方法应考虑的基本问题。     

生活垃圾焚烧烟气中重金属排放水平及影响因素分析

通过对浙江省生活垃圾焚烧炉排放烟气中重金属的监测,分析生活垃圾焚烧烟气中重金属排放水平。结果表明,汞及其化合物的检出率最高,为95.7%,其次为铬和锰,检出率均为60%,且在不同的焚烧炉中重金属排放浓度差异较大,检出率最低的为铊和镉,且排放浓度均较低;焚烧炉排放烟气中汞及其化合物、镉+铊及其化合物、锑+砷+铅+铬+钴+铜+锰+镍及其化合物排放浓度均低于国标排放限值,最大占标率分别为76%、4%、21.9%。焚烧烟气中的重金属含量与焚烧垃圾中的重金属含量有关,烟气通过废气处理设施,可有效地减少重金属等污染物的排放。     

统计学在垃圾焚烧飞灰浸提液重金属检测准确性研究中的应用

为提高复杂基体重金属检测准确性,在使用电感耦合等离子体发射光谱法检测生活垃圾焚烧飞灰浸提液时,进行标准曲线法、标准加入法和内标法3种定量校准方法比对。3种方法报出结果经过加标回收率换算后的样品原值具有明显一致性,使用统计学方差齐性和单因素方差分析验证了该一致性成立,表明内标法的精密度和准确度与标准曲线法、标准加入法无显著性差别。以3种方法样品原值的算数平均值作为样品最佳估计值评价各方法实际报出结果准确性,标准加入法准确性最好;稀释后的样品内标法加标回收率明显优于标准规定,受稀释倍数影响不大,工作效率高,满足HJ 781—2016质控要求,建议可作为该标准的补充;建议批量样品检测时优先采用内标法。3种方法样品原值一致性的验证,有助于执法、科研中对于复杂基体重金属物质含量的准确判断。     

Modeling Waste Incineration for Life-Cycle Inventory Analysis in Switzerland

This paper proposes a mathematical model for life-cycle inventory analysis (LCI) of waste incineration in Switzerland. In order to model conventional and new incineration technologies adequately, fundamental aspects of the different technologies relevant for the LCI are discussed. The environmental impact of these technologies strongly depends on the assessment of the long-term emissions of the solid incineration residues and is therefore related to value based decisions about the time horizon considered. The article illustrates that the choice of the landfill model has a significant influence on the results of life-cycle assessment of waste incineration.     

Bioavailability of Metals in Fly Ash and Their Bioaccumulation in Naturally Occurring Vegetation: A Pilot Scale Study

A pilot scale study was conducted to find out the different forms of metals if fly ash (FA) and bioaccumulation of these metals in the naturally growing vegetation on FA dumps. The total, acid extractable, bioavailable and water soluble fraction of metals of Fe, Cu, Mn, Zn, Ni, Co and Pb, and their bioaccumulation coefficients (BAC) on naturally growing vegetation were determined. FA samples had a neutral pH, low electrical conductivity, low organic C and trace amounts of N and P. The relative abundance of total metals in FA were found in the order Fe ≤ ≤ Zn ≤ Ni ≤ Co ≤ Cu. The concentration of bioavailable (DTPA) metals depend on the type and nature of coal used in thermal power stations. In the water the extract solution, only Fe and Zn were found above detection limits. After one year only four species of naturally occurring herbaceous vegetation were found growing and Cynodon dactylon (grass) covered almost entire surface of the FA. Iron accumulated to the greatest extent in vegetation followed by Mn, Zn, Cu, Pb, Ni and Co. The sequence of BAC for different metals were Fe (202) ≤ Mn (90) ≤ Zn (63) ≤ Pb (49) ≤ Ni (41) ≤ Cu (24). The experimental study revealed that Cynodon grass could be used for remediation of fly ash without any amendments, as this grass species act as metal excluder type.     

Accumulation of Heavy Metals in Epiphytic Lichens Near a Municipal Solid Waste Incinerator (Central Italy)

The epiphytic lichen Parmelia caperata was usedas biomonitor in the area of a municipal solid wasteincinerator (Poggibonsi, central Italy) to investigatethe levels and the spatial distribution of the heavymetals Al, Cd, Cr, Cu, Fe, Hg, Pb and Zn. Levels ofAl, Cu and Hg were similar to those in unpollutedareas, whereas high values were found for Cr, Zn andespecially Cd. The distribution pattern of the lastthree metals and the exponential relationship of theirconcentrations with distance from the incinerator,showed that the disposal plant is a local source ofatmospheric pollution due to Cd, Cr and Zn. For thesemetals, long-term hazard should be seriously taken into account.     

Impact of Fly Ash from Coal-Fired Power Stations in Delhi, with Particular Reference to Metal Contamination

Indraprastha Power Station (IPP Stn) and Rajghat Power House (RPH), owned by Delhi Electric Supply Undertaking, are both coal-fired power stations located on Ring Road in New Delhi. Ash content of the coal used ranges between 38–47%. The ash is collected in electrostatic precipitators which have an efficiency of 99.3% (IPP station), and 99.7% (RPH). There are instances of major dust pollution around the power stations from fly ash dispersal. The main method of disposal of fly ash from the power stations is by mixing with water, the resultant slurry is pumped through pipes to ash disposal ponds. The supernatant from these ponds is discharged into River Yamuna. Field studies have revealed large quantities of fly ash being deposited into the river. Local populations of Eichhornia crassipes have reduced dramatically between 1987–1995, with a marked reduction in the year 1994–1995. Field studies, conducted in January, 1995 have investigated the impact of fly ash dispersal in the Delhi region with particular reference to metal contamination. Elemental concentrations for a range of elements are determined by ICP-AES in fly ash and top soils along four transects from the power stations up to a distance of 8 km. The effects of fly ash leachates from the ash settling ponds on the river are determined by analyzing river overbank soils and vegetation for their elemental contents. It is concluded that fly ash dispersal from the stacks are a source of alkali, alkaline-earth and to some extent heavy metals in soils in the vicinity of the power stations, and enrichment of elements in river overbank soils are a result of discharge of fly ash leachates from ash disposal ponds. However, the impact from both these sources of metal contamination is not large enough to give cause for concern. Marked reduction in populations of Eichhornia crassipes downstream of the river where it receives leachates from the ash disposal ponds are attributed to turbidity of the ash pond leachates and metal toxicity. Elemental enrichment in the floodplain soils, as a result of fly ash particle deposition during monsoons, may enhance the horticultural value of these soils as is shown by a healthy cultivated crop of Brassica juncea.     

示波极谱滴定法测定水和废水中的溶解氧

在pH值为6.5的NaAc-HAc底液中,加入经处理后的水样10ml,用EDTA标准溶液滴定其中的Mn^2 ,以EDTA在示波极谱上的切口到一定深度指示终点,废水的色度、浊度等对测定不产生干扰,不需进行预处理,操作简便、快速。该方法的相对误差小于1.0%,变异系数小于0.7%。     

富集采样法监测空气和废气样品时采样体积的确定方法

讨论了富集采样法监测空气和废气样品时确定采样体积的主要因素,给出了富集采样法监测空气和废气样品时采样体积的确定方法和实例。     

Assessment of Ground Water Vulnerability and its Application to the Development of Protection Strategy for the Water Supply Aquifer in Owerri, Southeastern Nigeria

Pollution vulnerability of theOwerri regional water supply aquifer wasevaluated as a basis for developing appropriateprotection strategy for the groundwaterresource. The assessment was accomplished usingLegrand, GOD, Siga and DRASTIC models.Techniques of the models generally involvedparameters rating and point count systems, whichare based on the evaluation of various parameterin relation to their capacity for enhancing orattenuating contaminants in the groundwatersystem. Field and laboratory evaluations of theparameters indicate that the Owerri areagenerally occupies a nearly, flat topographywith a relatively high groundwater recharge. Thearea is underlain by predominantly sandyfacies in the Northern area which grades intogravelly sequences towards the southwest. TheSoutheastern area is distinguished by thickclayey facies that thin westwards towards theOwerri metropolis. Effective hydraulicconductivity (Kz) in the downward directionranges from 1.44 × 10^-3 to 5.6 × 10^-9 m s^-1; with the upper limits reflecting coarsesands and gravelly units. The amount of clay andclay-size particles in the sandy and gravellyunits is negligible, suggesting that thesorptive capacity of the units is low. Depth towater table decreases southwards while hydraulichead gradients vary between 0.09 and 0.22.Groundwater occurs in unconfined conditions inmost places except in the southeastern zonewhere it is semi-confined due to the presence ofa clayey unit. The groundwater vulnerabilitymap developed on the basis of the models andseveral other thematic maps shows that theOwerri metropolis and the southwest area ofOwerri have high vulnerability, indicatinggroundwater pollution. The existing wastedisposal sites in these sub-areas should beabandoned and rehabilitated to forstall furtherpollution of the groundwater system. Areas tothe North and Southeast of Owerri have moderateand low vulnerabilities, respectively,indicating the relatively lower sensitivity ofthe groundwater system in the sub-areas tocontamination. The lower sensitivity couldfurther be matched with properly engineeredsanitary landfills in the event of choice ofsites, as an additional protective strategy forthe groundwater system.     

微波消解石墨炉原子吸收法测定工业废气中铍及其化合物

采用玻璃纤维滤筒采集工业废气中铍及其化合物,硝酸-氢氟酸混酸体系微波消解滤筒、硝酸镁一硝酸混合液作为基体改进剂,石墨炉原子吸收法测定铍。本方法前处理操作过程简单、省时、酸用量少、环境污染小,方法的灵敏度和准确度都有很大的提高。当采样体积为30L,工业废气中铍的最低检出质量浓度为1×10μmg／m^3。