The influence of sewage sludge properties on sludge-borne metal availability

With the advent of more stringent controls on wastewater treatment, sewage sludge production in Europe and many parts of the world is increasing. With this increase comes the problem of sludge disposal, and recycling to land arguably offers an economically and environmentally sustainable option. However, a major limitation of sewage sludge reuse is the potential release of heavy metals from the sludge and heavy metal accumulation to toxic levels in topsoils. The properties of the sludge play a crucial role in determining the initial release and subsequent availability of heavy metals in amended soils. Bioavailable forms of heavy metals in recently amended soils are most likely to be those that are bioavailable in the sewage sludge. In this paper, published research on the importance of sewage sludge characteristics on metal release and bioavailability will be reviewed and contrasted with original research. A selection of sludges from around Australia has been collected for this purpose. Through the use of incubation studies, isotope dilution techniques, ion-selective electrode measurements and ¹³C-NMR spectroscopy, the importance of a range of sludge properties on heavy metal behaviour in sludges and sludge-amended soils is addressed.     

Trace element speciation in selected smelter-contaminated soils in Anaconda and Deer Lodge Valley, Montana, USA

Long-term copper smelting in the Anaconda and Deer Lodge Valley area of Montana has resulted in an extensive area of trace element contamination. Aerial extent of contamination is generally established, but total analysis of soils does not correlate to relative degree of impact on vegetation growth. Three pedons (Beaverell, Cetrack and Judco) were analyzed by routine soil characterization methods, aqua regia microwave digestion, sequential chemical extraction, and X-ray diffraction analysis with the objective of providing a better understanding of chemical forms and potential reactivity of selected trace elements (Cd, Co, Cr, Cu, Hg, Mn, Ni, P, Pb). Surface horizons of soils are more acidic than subsoils, with pH for all horizons ranging from 4.0 to 8.7. Beaverell is the most contaminated in the upper 20 cm with the sum of total extractable (SUM_TE) trace elements by microwave digestion ranging from 1836 to 3605 mg kg⁻¹, largest H₂O-soluble (WS) and exchangeable (EX) fractions (e.g. 1.6 and 9.3%, respectively), and smallest residual (RES) fraction (e.g. 14.3%). Cetrack has greater SUM_TE elements than Judco, though a lower WS+EX fraction due to the effects of alkaline pH, carbonates and high P. Oxide (OX), organic matter/sulfide (OM/S), and RES fractions predominate over WS, EX, and specially-sorbed/carbonate-bound fractions (SS/CAR) for all horizons. Copper, Zn, Pb and Cd are elevated in surface over subsurface horizons in these latter fractions, indicating these elements were anthropogenic additions. X-ray data indicate that Pb, Cu, Cr and Cd partially exists as both OX and sulfide mineral forms.     

生物膜填料塔处理浓度有机废气的工业应用试验研究

工业应用试验研究表明，生物膜填料塔处理工业有机废气是可行的，当运行条件控制适当时，净化效率可保持在90％以上，能够实现达标排放，这一成果填补了我国环保工业技术领域的空白，工程技术上接近现阶段国外的技术研究水平。     

应用改进密切值法进行地表水环境综合评价

针对密切值法应用中的实际问题,引入目标差值率和虚拟优点、劣点的概念,对密切值法进行了改进.将改进后的密切值法应用于地表水环境综合评价中,经实例分析表明,该方法概念清晰、计算简便实用,且从评价结果可获许多潜在的信息,是开展地表水流域水环境综合评价的一种有效的方法.     

藻类吸附法去除废水中的重金属

介绍了藻类吸附法处理重金属废水的研究现状,讨论了不同藻类的预处理方法和吸附能力,总结了藻类吸附水中重金属的效果、影响因素、机理和规律,展望了藻类在重金属废水处理中的应用前景。     

用植物清除土壤中的重金属

介绍了生物修复技术去除土壤中的重金属及对植物的要求.植物能去除土壤中的有毒金属,将金属富集在生物体内,或将金属变成挥发性气体.     

烟气脱硫(FGD)工程设计框架

在国家实施“总量控制”和“两控区”的重要环境保护政策下,烟气脱硫（ＦＧＤ）工程提到了可持续发展的议事日程,实施ＦＧＤ工程是投资大、直接经济效益不显著的环境工程。因此在全面论述实施ＦＧＤ工程的设计框架,即各设计阶段应考虑的几个重大因素和必须遵循的一系列规则基础上,着重对目前国内外主要的ＦＧＤ工艺进行了技术经济分析评述,提出选择ＦＧＤ工艺的８条重要原则。供重大决策参考和推动环境目标的实现。     

坡道式停车库空气质量及影响因素

为了解不同形式坡道式 车库中汽车尾气污染状况，对４座典型的坡道式停车库进行了空气质量监测，并同时进行车流量统计、计算和分析了信车库内污染物浓度与车流量之间的相关性，监测结果表明，停车库ＮＯｘ和ＣＯ浓度符合相应标准，而地下停车库排气Ｏｘ有超桔现象。结论是地面停车主轵成于地下停车库，地下停车库的送排风系统必须合理设置。     

含硫化合物的气相色谱检测响应特性研究

利用气相色谱（配炎焰光度检测器）对二硫化碳（ＣＳ２）、甲硫醇（ＣＨ３ＣＨ）、甲硫醚（ＤＭＳ）和二甲二硫醚（ＤＭＤＳ）４种含硫物质进行了分析检测，着重讨论了气相色谱仪的各项参数对几种含硫物质响应和分离效果的影响。结果表明：该分析对含硫气体的最小检测浓度达到ｐｐｂ级。在各项参数中，色谱柱温度在Ｎ２压力对各含硫物质响应和分离度影响最大，汽化室和检测器温度及空气压力对它们的影响相对较小。     

上海城市交通与机动车排气污染调查

上海市机动车保有量逐年增加，车辆的排气污染愈来愈严重，据调查，１９９７年机动画排放的ＣＯ，ＭＮＨＣ，ＮＯＸ和ＰＭ分别达到５８．６，９．０８，６．２０和０．２３万吨。中心城区机动车排放的ＣＯ，ＮＭＨＣ和ＮＯＸ污染物５０％以上来自于小型车，是影响上海城区环境空气质量的主要污染源。