恶臭源厂界空气中恶臭物质监测技术要点及结果分析探讨——以西安市某大型垃圾填埋场为例

建立了水杨酸-次氯酸钠法分析氨的标准曲线,通过对西安市某垃圾填埋场的实地监测,探索了恶臭气体中氨气的分析方法。分析了臭气、氨气、硫化氢之间的浓度相关性,利用本次监测数据,找出了针对该垃圾处理场的高浓度氨气样品初步分析方案。恶臭产生的主要点位为垃圾场渗滤液污水处理站及下游区域,垃圾场臭气呈现出由点源污染(作业面)到面源污染扩散的态势。     

预冷冻浓缩系统与气相色谱-质谱联用测定空气中挥发性有机物

采用预冷冻浓缩系统和气相色谱-质谱联用,建立了测定空气中39种挥发性有机物的分析方法,该法用苏玛罐或Tedlar气袋采集空气样品经-160℃液氮预冷冻浓缩后,用GC-MS检测.该方法采样简便,灵敏度、准确度高,已应用于室内空气和环境空气的测定,取得满意的结果.     

预浓缩系统与PFPD检测器联用测定环境空气中四氢噻吩

采用预浓缩系统与GC-PFPD联用,建立了环境空气中四氢噻吩的分析方法,该法用苏玛罐或Tedlar袋采集空气样品在预浓缩系统中经液氮于-160℃冷冻浓缩后,用GS-GASPRO专用毛细管色谱柱及GC-PFPD检测。四氢噻吩的最低检出限为2·0μg/m3。经6次的重复测定,其相对标准偏差小于5·0%。该方法已用于环境空气中四氢噻吩的测定,取得了令人满意的结果。     

环境空气中痕量挥发性有机硫监测分析方法研究

采用预浓缩系统与GC MS联用,建立了环境空气中痕量挥发性有机硫的分析方法,该法用苏玛罐或Tedlar袋采集空气样品在预浓缩系统中经液氮于-160℃冷冻浓缩后,进入GC MS进行分析。甲硫醇、乙硫醇、甲硫醚、乙硫醚、二甲二硫的最低检出限分别为2 0、1 0、1 0、1 0、0 5μg m3。经6次的重复测定,其相对标准偏差小于9 0%。该方法已用于环境空气的测定,取得了令人满意的结果。     

预浓缩气相色谱-质谱技术测定气体中六氟化硫

六氟化硫(SF6)是《京都议定书》所列的温室效应较强的一种温室气体。建立了气相色谱-质谱联用(GC-MS)、大气预浓缩系统分析测定气体中六氟化硫的方法。实验结果表明,该方法测定SF6气体的相对标准偏差为8.41%,线性范围为17.2×10-12～645×10-12,回收率为81.08%,方法检出限为5.28×10-12。该方法操作简便准确,分析时间短,适用于实验室分析。     

生活垃圾转运站恶臭污染指标初探

报道了广州部分垃圾转运站恶臭指标的检测结果.发现国家标准(GB14554-1993)中的单项污染物指标的测定值大多远低于标准限值,而综合指标臭气浓度普遍超标,两类指标间存在严重不符.利用SAS统计软件综合分析各指标的检测数据,结果表明,垃圾转运站臭气中恶臭指标的含量存在较大的变异,且在垃圾站内的变异程度更大;恶臭单项指标在垃圾站内和垃圾站边界点的测定均值问无显著差异;臭气浓度和恶臭单项指标整体间可能存在一定的线性关系,但和某个具体的恶臭指标的线性相关性并不显著.     

流动注射在线富集分离荧光分光光度计测定垃圾渗出液中的苯酚

建立了用荧光分光光度计作为流动注射分析的检测器 ,用自行研制的流通池测定垃圾渗出液中苯酚的新方法。方法的线性范围为 0 .0 9～ 0 .6mg/ L,检出限为 5 μg/ L。用于垃圾渗出液的测定 ,结果与 4-氨基安替吡啉法无显著性差异 ,回收率在 96%～ 10 3 %之间 ,该法具有选择性好、灵敏度高、重现性好的特点     

苏州吴江区某生活垃圾受控(简易)填埋场整治工程污染现状及评价浅析

2018年9月对苏州吴江区某生活垃圾受控(简易)填埋场整治工程进行土壤及地下水相关指标进行现场采样和实验室分析。通过采样分析发现:该生活垃圾填埋场周边环境土壤中无机物指标铬、铅、镉、砷、汞、铜、锌、镍含量均达到相关标准,土壤中53种挥发性有机物均未检出。地下水中氨氮、耗氧量、1,2-二氯乙烷含量均不符合标准要求。超标的主要原因是该生活垃圾简易填埋场建设期按未规范采取防渗措施,致使渗滤液向场地周边渗漏,污染地下水质。     

垃圾填埋场地下水污染对居民健康的风险评价

调查了某垃圾填埋场地下水和周边居民饮用水中的As、Hg等重金属和挥发酚等有机物的污染状况，运用美国环保局的健康风险计算模型，评估了该垃圾填埋场地下水对周边居民的潜在健康风险。结果表明，各类人群对4种有阈化合物的饮食和皮肤暴露的终身健康危险度在8．2×10^-11～1．3×10^-10之间，均低于可以接受的风险水平10^-6；对As的终身超额健康危险度在3．1×10^-7～4．9×10^-7之间，表明地下水中砷污染对居民潜在的致癌风险不明显。各类人群通过皮肤对Hg、As、Cd和挥发酚的暴露剂量比通过饮水暴露的剂量高0．7倍～14．5倍，皮肤暴露将是地下水影响人体健康并构成潜在风险的重要途径。     

丽江垃圾填埋场地质环境影响因素及适宜性评价

生活垃圾卫生填埋场的选址涉及多方面因素,该文通过对丽江市生活垃圾填埋的历史与现状、填埋量、填埋场分布等状况的分析,用层次分析法对正在使用填埋场进行适宜性评价,分析了导致污染的主要环境地质问题,对已污染填埋场的治理和未来填埋场的选址具有指导意义.     

北京市废弃物处理温室气体排放特征

基于《2006年IPCC国家温室气体清单指南》推荐的方法，结合《省级温室气体清单编制指南（试行）》和《城市温室气体核算工具指南》的部分数据与核算范围，针对固体废弃物填埋、焚烧和废水处理等过程，核算了北京市2005-2014年废弃物处理过程中温室气体总排放量。结果表明：2005-2014年北京市废弃物处理过程温室气体总排放量呈逐渐上升趋势，2014年温室气体总排放量比2005年增长98%。10年间，固体废弃物填埋过程一直是最主要的温室气体排放源，到2014年排放量达到最大，为416.3×10⁴t二氧化碳当量（CO₂e）。废弃物填埋、废水处理和废弃物焚烧过程占总排放量的比例分别为78.5%（CO₂e质量分数，下同）、13.5%和8%。结合已有研究，系统优化国内7个典型城市废弃物处理温室气体排放因子，核算7个城市排放情况，并对比分析了北京市排放情况。     

生活垃圾填埋场覆盖膜破损及其环境影响

中国的垃圾填埋场目前多采用高密度聚乙烯膜(HDPE)进行覆盖,已建成的填埋场均存在不同程度覆盖膜破损现象。采用填埋气泄漏可视化检测技术对中国东部某大型生活垃圾填埋场开展覆盖膜完整性检测,揭示了覆盖膜破损特征及破损成因,明确了破损点泄漏量,评估了其温室效应影响,梳理了国内外填埋场覆盖层监管相关管理规定和措施。结果表明:尖锐物体应力损伤导致的破损是填埋场覆盖膜破损的主要类型,粗放施工、监管机制不足、维护管理不到位是造成填埋场覆盖膜破损的主要原因。破损点的甲烷泄漏量约为817.2 m³/d,约合每年向大气环境释放温室气体超过4 900 t CO₂-eq。完善填埋场污染控制标准和技术规范、加强填埋场覆盖膜完整性的监管,是控制填埋场温室气体排放和推进固废处置设施碳减排的重要举措。     

COMBUSTIVE APPROACH FOR MEASURING TOTAL VOLATILE PHOSPHORUS CONTENT IN LANDFILL GAS

A technique was developed to measure the total gaseous phosphorus content in biogas. The amount of air needed for a neutral to oxidising flame was mixed with the biogas. The gas mixture was burnt in a closed quartz burner and the combustion gasses were bubbled through a nitric acid solution. The phosphate content in the bubbling liquid was determined with sector field ICP-MS. The technique was validated in the lab with phosphine. Afterwards the set-up was installed on a landfill. The total gaseous phosphorus content in the landfill gas, measured with the combustive technique, ranged from 1.65 to 4.44 g P/m³. At the same time the phosphine concentration in the landfill gas was determined gas chromatographically (GC). The phosphine (PH₃) content measured with GC ranged from 7.6 to 16.7 g PH₃-P/m³. Since the phosphine-P content (GC) was consistently higher than the total gaseous phosphorus content (burner/ICP-MS), the hypothesised presence of highly toxic gaseous phosphorus compounds other than phosphine could not be demonstrated.     

The Emissions of Major Aromatic Voc as Landfill Gas from Urban Landfill Sites in Korea

In this study, concentrations of major aromatic VOCs were determined from landfill gas (LFG) at a total of five municipal landfill sites in Korea including Nan Ji (NJ), Woon Jung (WJ), Sam Poong (SP), Hoei Chun (HC), and No Hyung (NH). The concentration levels of those VOC were found to be significantly different, mainly as a function of such a parameter as landfill aging. The VOC concentrations measured from the unclosed landfill sites (e.g., WJ) were characterized by exceedingly high values above a few tens of ppm. However, the results of the abandoned site (e.g., SP) were about three orders of magnitude lower than the others so as to merely exceed the typical ambient concentration levels. It was most striking to find a systematic dominance of toluene over other aromatic VOC under most circumstances. The LFG flux values of all aromatic VOC and the four specific major ones (termed as BTEX: benzene, toluene, ethylbenzene, and xylene) were also computed for each vent pipe from all study sites using their concentrations and the concurrently determined environmental parameters. The results, if calculated in terms of the average BTEX quantity emitted per vent pipe, showed that the magnitude of their emissions can vary substantially, with the values ranging from 0.05 (SP) to 49.2 kg yr⁻¹ (WJ in wintertime). The LFG flux values of aromatic VOC, when compared to the contribution of non-methane hydrocarbons (NMHC), were able to explain a constant, but minor, proportion of the LFG carbon budget.     

Solid waste characteristics and their relationship to gas production in tropical landfill

Solid waste characteristics and landfill gas emission rate in tropical landfill was investigated in this study. The experiment was conducted at a pilot landfill cell in Thailand where fresh and two-year-old wastes in the cell were characterized at various depths of 1.5, 3, 4.5 and 6 m. Incoming solid wastes to the landfill were mainly composed of plastic and foam (24.05%). Other major components were food wastes (16.8%) and paper (13.3%). The determination of material components in disposed wastes has shown that the major identifiable components in the wastes were plastic and foam which are resistant to biodegradation. The density of solid waste increased along the depth of the landfill from 240 kg m⁻³ at the top to 1,260 kg m⁻³ at the bottom. Reduction of volatile solids content in waste samples along the depth of landfill suggests that biodegradation of solid waste has taken place to a greater extent at the bottom of the landfill. Gas production rates obtained from anaerobic batch experiment were in agreement with field measurements showing that the rates increased along the depth of the landfill cell. They were found in range between 0.05 and 0.89 l kg⁻¹ volatile solids day⁻¹. Average emission rate of methane through the final cover soil layer was estimated as 23.95 g⁻²day⁻¹ and 1.17 g⁻²day⁻¹ during the dry and rainy seasons, respectively.     

气相色谱法测定工业废气中的异丙醇

用活性炭吸附管采集吸附工业废气中的异丙醇,经二硫化碳解析后由自动进样器送入气相色谱仪中分离并由FID检测器检测。2 mL二硫化碳解吸溶剂中异丙醇的绝对量为1.57~6.28 mg时,测定结果的相对标准偏差为2.4%~7.6%(n=5);当样品采集量为10 L时,方法检出限为0.3 mg/m³。所用活性炭采样管对异丙醇的吸附效果良好,100 mg活性炭对异丙醇的穿透容量大于15 mg;二硫化碳溶剂对吸附在活性炭中的异丙醇解吸效果较好,异丙醇加标量为3.92~15.70 mg时,解吸效率为93.9%~100.5%。     

电子制冷预浓缩仪-气相色谱-质谱法测空气中含硫化合物

建立电子制冷预浓缩仪-气相色谱-质谱法测定空气中10种含硫化合物的方法。经考察不同采样容器、优化预处理条件、研究样品保存等获得了最佳实验条件,并通过实际样品的测定,考察了方法的适用性。结果表明:硫化氢、甲硫醇和乙硫醇3种高活性含硫化合物校准曲线线性回归系数在0.990以上,另外7种含硫化合物在0.995以上;高、中、低空白加标样品相对标准偏差均为9.5%以内,乙硫醇由于具有高活性和吸附性,低浓度空白加标回收率为63%,其余组分回收率范围为83%~110%;当进样体积为400 mL时,各目标化合物的方法检出限为0.2×10^-3~1.1×10^-3 mg/m³。分析污水处理厂无组织排放监控点的空气结果显示,该方法具有较低的检出限及较强的抗干扰能力,能较好地满足目前监测工作的要求。     

超低排放下燃煤电厂颗粒物排放特征分析研究

选取6家经过超低排放改造的燃煤电厂,对湿法脱硫(WFGD)和湿式电除尘器(WESP)进出口烟气中TPM、PM_(10)、PM_(2.5)、PM_1进行测试,分析研究超低排放下燃煤电厂颗粒物的排放特征及电除尘器后净化设备对颗粒物的脱除效果。结果表明,6家电厂TPM、PM_(10)、PM_(2.5)、PM_1排放浓度分别为0.75~2.36、0.71~2.12、0.65~1.96、0.51~1.57 mg/m~3。分析烟气中颗粒物粒径分布可知,除尘器后,PM10占TPM质量比低于40%,且比例随烟气经过WFGD和WESP而逐渐降低。WFGD对PM2.5有较好的脱除效果,而WESP对PM1脱除效果显著。为满足超低排放标准,6家电厂除尘器后脱除设备综合除尘效率大多在85%以上。计算得到6家电厂TPM、PM_(10)、PM_(2.5)、PM_1排放因子,与超低排放改造之前同等级燃煤电厂相比,6家电厂不同粒径颗粒物排放因子均显著降低,也远低于西方发达国家燃煤电厂颗粒物排放因子。     

The effect of atmospheric pressure on CH4 and CO2 emission from a closed landfill site in Manchester, UK

A time series study was conducted to ascertain the effect of barometric pressure on the variability of CH₄ and CO₂ concentrations in a closed landfill site. An in situ data of methane/carbon dioxide concentrations and environmental parameters were collected by means of an in-borehole gas monitor, the GasClam (Ion Science, UK). Linear regression analysis was used to determine the strength of the correlation between ground-gas concentrations and barometric pressure. The result shows CH₄ and CO₂ concentrations to be variable with weak negative correlations of 0.2691 and 0.2773, respectively, with barometric pressure over the entire monitoring period. Although the R ² was slightly improved by considering their concentration over single periods of rising and falling pressure, single periods of rising pressure and single periods of falling pressure, their correlations remained insignificant at 95 % confidence level. The result revealed that atmospheric pressure—the acclaimed major control on the variability of ground-gas concentration—is not always so. A case was made for the determination of other possible controls such as changes in temperature, soil permeability, landfill water depth, season, and geology of the borehole and also how much of control each factor would have on the variability/migration of CH₄ and CO₂ concentrations from the studied landfill.     

Empirical gas emission and oxidation measurement at cover soil of dumping site: example from Malaysia

Methane (CH₄) is one of the most relevant greenhouse gases and it has a global warming potential 25 times greater than that of carbon dioxide (CO₂), risking human health and the environment. Microbial CH₄ oxidation in landfill cover soils may constitute a means of controlling CH₄ emissions. The study was intended to quantify CH₄ and CO₂ emissions rates at the Sungai Sedu open dumping landfill during the dry season, characterize their spatial and temporal variations, and measure the CH₄ oxidation associated with the landfill cover soil using a homemade static flux chamber. Concentrations of the gases were analyzed by a Micro-GC CP-4900. Two methods, kriging values and inverse distance weighting (IDW), were found almost identical. The findings of the proposed method show that the ratio of CH₄ to CO₂ emissions was 25.4 %, indicating higher CO₂ emissions than CH₄ emissions. Also, the average CH₄ oxidation in the landfill cover soil was 52.5 %. The CH₄ and CO₂ emissions did not show fixed-pattern temporal variation based on daytime measurements. Statistically, a negative relationship was found between CH₄ emissions and oxidation (R ²?=?0.46). It can be concluded that the variation in the CH₄ oxidation was mainly attributed to the properties of the landfill cover soil.