伊朗东北部萨卜泽瓦尔蛇绿岩带Baghejar铬铁矿周边土壤的镍、铬污染分析与评估（英文）

主要分析伊朗东北部萨卜泽瓦尔蛇绿岩带Baghejar铬铁矿(BCM)周边土壤的镍、铬浓度,采用污染指数评估土壤污染程度。土壤样品(深度为0~20cm)采于距BCM矿不同距离的地点。采用原子吸收光谱测定土壤样品中重金属(铬和镍)含量。绘制等高线图描述重金属的空间分布,同时对金属污染程度进行了量化。结果表明,采样地土壤受到铬和镍污染。铬和镍的相应浓度分别达到(156.19±24.45)和(321.7±133.27)mg/kg,超出对应的土壤最大允许浓度。各种指数显示出铬铁矿周边土壤显著受到铬和镍污染,超出正常范围数倍之多。研究表明,重金属浓度随着与矿区距离增加而增加。采矿产生的污染可以迁移到距源头较远的地方。     

硫酸盐侵蚀条件下固化重金属污染土强度及浸出特性（英文）

污染土修复常采用固化稳定化技术。固化稳定化重金属污染土在酸侵蚀条件下其重金属离子会重新溶出,从而导致对周边环境的二次污染。以常用的水泥、粉煤灰和石灰为固化剂原料,设计不同组合及配比的固化剂,通过无侧限抗压强度试验及硫酸/硝酸法毒性浸出试验研究固化重金属污染土在酸侵蚀条件下的强度及浸出特性。探讨固化剂类型、硫酸盐浓度(1.5,3.0,6.0 g/L)和侵蚀龄期(0,7,14,28 d)对固化重金属污染土的强度及溶出浓度的影响,并引入固定率参数,进一步量化考察侵蚀龄期和侵蚀浓度对重金属离子固定率的影响。结果表明:重金属离子的浸出量随着硫酸盐侵蚀浓度和侵蚀龄期的增加而增加;相对而言,含氧化钙的固化剂对重金属污染土的固化效果较差,重金属离子浸出量大,固化率低。     

地表水重金属污染监测现状与对策

当前我们国家的各项经济生活和社会生活都在发生变化,这种情况加快了各种矿产资源和金属资源的开发利用率。也使得我国的环境问题更加的突出,大气污染、水污染以及土壤污染等,都为自然环境的发展带来了沉重的负担。在这些污染中地表水重金属污染受到了社会各界的关注,同时也是高危险性的影响之一。重金属污染中含有较多的有毒物质,尤其是对地表水的污染,因此必须充分重视地表水金属污染的检测。     

氧化亚铁硫杆菌淋滤重金属污染底泥的动力学

针对氧化亚铁硫杆菌生物(T.f)淋滤法处理重金属污染底泥进行实验研究。采用分批摇床培养方法,分析生物淋滤过程中Fe~(2+)浓度对底泥酸化、微生物生长、Fe~(2+)氧化以及底泥中重金属溶出率的影响;借助Monod方程得到不同Fe~(2+)浓度下氧化亚铁硫杆菌的最大比生长速率及饱和常数;通过经验方程推导出不同Fe~(2+)浓度下重金属离子Cu~(2+)和Zn~(2+)的溶出速率常数。结果表明,当Fe~(2+)浓度由2.0 g/L增加到10.0 g/L时,氧化亚铁硫杆菌的最大比生长速率由0.126 h~(-1)上升到0.159 h~(-1),饱和常数由0.881 g/L下降到0.327 g/L,重金属的溶出速率常数与Fe~(2+)浓度呈正相关;当Fe~(2+)浓度超过10.0 g/L时,氧化亚铁硫杆菌的最大比生长速率降低,而饱和常数增大。随着Fe~(2+)浓度的增加Fe~(2+)氧化速率增大。综合各个动力学参数可知,Fe~(2+)浓度为10.0 g/L是生物淋滤体系的最佳底物浓度。     

电镀污泥的重金属湿法回收资源化技术及展望

电镀污泥含有一定量的铜、镍、铬、锌等金属,属于危险废物。对其中的金属（尤其是重金属）进行资源化利用,将有效消除电镀污泥重金属污染的危害,又能带来可观的经济和环境效益,成为电镀污泥处理技术发展的重点。本文介绍了湿法回收重金属技术,其中湿法加压氢还原技术具有选择性高、回收率高、工艺成熟的优点,适合于成分复杂的电镀污泥重金属回收,具有较高的应用前景。     

电镀污泥的重金属湿法回收资源化技术及展望

电镀污泥含有一定量的铜、镍、铬、锌等金属,属于危险废物.对其中的金属(尤其是重金属)进行资源化利用,将有效消除电镀污泥重金属污染的危害,又能带来可观的经济和环境效益,成为电镀污泥处理技术发展的重点.本文介绍了湿法回收重金属技术,其中湿法加压氢还原技术具有选择性高、回收率高、工艺成熟的优点,适合于成分复杂的电镀污泥重金属回收,具有较高的应用前景.     

Pannonibacter phragmitetus对Cr(Ⅵ)污染土壤的修复效应

在前期从铬渣污染土壤中分离筛选出高效还原Cr(Ⅵ)的土著微生物(Pannonibacter phragmitetus)的基础上,通过单因素实验对所筛选的土著微生物修复模拟铬污染土壤效应及其影响因素进行研究.结果表明: 土著微生物对土壤中Cr(Ⅵ)的修复受pH值、微生物接种量和初始Cr(Ⅵ)浓度的影响;pH值越高、微生物接种量越大而初始Cr(Ⅵ)浓度越低时,Cr(Ⅵ)的修复速率越快;所筛选的土著微生物在316 h内就能够完全还原污染土壤中浓度为360 mg/kg的Cr(Ⅵ);Cr(Ⅵ)的修复是土著微生物(Pannonibacter phragmitetus)通过酶促反应对Cr(Ⅵ)的直接还原所致.     

从铜镍电镀污泥中提取铜和硫酸镍的试验研究

电镀污泥是电镀废水处理过程中产生的固体废弃物,它含有大量的重金属如铜、铬、镍、锌、铁等,是一种廉价的二次可再生资源。电镀污泥综合利用方面的研究报道很多,如采用氨浸电镀污泥,然后用氢还原分别回收铜、镍和锌;用萃取法回收污泥氨浸液中的金属资源;采用微生物净化法回收电镀污泥及废液中的铬和其它     

堆肥对重金属污染的水稻根际土壤细菌群落的剂量依赖性影响（英文）

在复合重金属污染的水稻土壤中分别添加1%、5%和10%(质量分数)的堆肥，150 d后观察土壤微生物群落的结构和组成变化。研究发现，堆肥对根际细菌群落的影响表现出剂量依赖效应。低等(1%)和中等(5%)堆肥添加量对根际细菌群落结构的影响比对非根际细菌群落的影响更大。根际土壤细菌多样性在添加堆肥后明显低于非根际土壤细菌多样性。冗余分析(RDA)结果表明，根际和非根际细菌群落对土壤理化性质(如p H、Pb、Cd和Cu含量)变化的响应不同，可能是根际和非根际细菌群落差异的原因之一。因此，在农业管理中应该考虑堆肥的施加对根际微生物的影响。     

大型铸钢件用镁铝质球形砂的研究

本研究针对大型铸钢件生产用铬铁矿砂存在的资源少、价格高、铬污染等问题,利用资源丰富的镁砂及高铝质材料,用人工制球及高温烧结工艺制作出一种新型铸造特种砂———镁铝质球形砂。该砂具有很高的耐火度和优异的抗金属渗透及粘砂的能力,粒形圆整,流动性及透气性好,无污染,在大型铸钢件上获得了良好的应用效果。     

Acid mine drainage and heavy metal contamination in groundwater of metal sulfide mine at arid territory (BS mine, Western Australia)

The issues of acid mine drainage (AMD) and heavy metals contamination in the metal sulfide mine in the arid district were explored, through studying the acidification and the heavy metals distribution and evolution of groundwater in the black swan (BS) nickel sulfide mine (Western Australia). The groundwater samples were collected from the drilling holes situated in the vicinity of tailings storage facility (TSF) and in the background of the mine (away from TSF), respectively, and the pH and electric conductivity (E_c) were measured in site and the metal contents were analysed by ICP-MS and ICP-AES, quarterly in one hydrological year. The results disclose that the TSF groundwater is remarkably acidified (pH_mean≈5, pH_min=3), and the average contents of heavy metals (Co, Cu, Zn, Cd) and Al, Mn are of 1–2 orders of magnitude higher in TSF groundwater than in background groundwater. It may be due to the percolation of tailings waste water from mill process, which leads the tailings to oxidize and the deep groundwater to acidify and contaminate with heavy metals. Besides, the heavy metals concentration in groundwater may be controlled by pH mainly.     

Diversity of microbial community at acid mine drainages from Dachang metals-rich mine, China

Two acid mine drainage (AMD) samples TS and WK, which were from the Dachang metals-rich mine in Guangxi province, China, were studied using PCR-based cloning approach. A total of 44 operational taxonomic units (OTUs) were obtained from the two AMD samples. However, only three OTUs (GXDC-9, GXDC-19 and GXDC-50) detected in sample TS can also be observed in sample WK. Phylogenetic analysis revealed that the bacteria in the two samples fell into four putative divisions, which were Nitrospira, Alphaproteobacteria, Gamaproteobacteria, and Acidobacteria. Organisms of genuses Acidithiobacillus and Leptospirillum, which were in gamaproteobacteria class and Nitrospira family, were dominant in two samples, respectively. In sample TS, which was characterized by low pH, high sulfate, high iron, and high arsenide, two species (Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans) constituted 98.22% of the entire microbial community. Compared with sample TS, the microbial community in sample WK was more diversified according to the observation. Interestedly, the Legionella species, which was rarely observed in the low-pH environment, was detected in sample WK. This work helps us to further understand the diversity of microbial community living in extreme acid mine drainages with unique geochemistry and the tolerance capability of acidophiles to heavy metal.     

Effect of sulfate erosion on strength and leaching characteristic of stabilized heavy metal contaminated red clay

Solidification/stabilization (S/S) technology has been widely used for remediation of the heavy metal contaminated soils. The heavy metal ions will be leached from the stabilized contaminated soil under sulfate erosion conditions, which gives rise to secondary contamination to the areas around the mine sites. The commonly used Portland cement, fly ash and quicklime were taken as binder raw materials with various mix proportions. And then, the sulphuric acid and nitric acid method was used to investigate the leaching characteristic of stabilized heavy metal contaminated soils. The effects of binder types and binder contents, sulfate concentrations (1.5, 3.0 and 6.0 g/L) and erosion time (0, 7, 14 and 28 d) on leached concentrations of heavy metal ions from contaminated soils were studied. Moreover, a parameter named immobilization percentage (IP) was introduced to evaluate the influence of erosion time and sulfate concentration on immobilization effectiveness for heavy metal ions. The results showed that, the leached heavy metal concentrations increased with sulfate concentration and erosion time. Comparatively speaking, the composite binders that had calcium oxide in it exhibited the worst solidification effectiveness and the lowest immobilization percentage, with the largest leached heavy metal concentration.     

铜陵重金属富集的尾矿废弃地酸性废水中细菌及古菌的多样性

为了加深对安徽省铜陵市不同重金属富集程度的尾矿附近酸性废水中微生物多样性的了解,运用PCR-16S r DNA克隆文库技术对酸性废水中细菌及古菌的群落结构进行研究。在铜陵的5个样点采集了8个水样。系统发育分析结果表明,酸性废水中的细菌主要是Betaproteobacteria,Gammaproteobacteria,Alphaproteobacteria,Deinococcus-Thermus,Nitrospira,Firmicutes,Actinobacteria,Deltaproteobacteria,Bacteroidetes,Chloroflexi,古菌是Thermoplasma,Ferroplasma以及Thermogymnomonas。根据细菌和古菌的组成对样品进行聚类分析,结果表明,5个样品由于优势菌株Thermomonas和Meiothermus拥有较高的相似度。2个样品由于Acidithiobacillus和Leptospirillum占主导也拥有较高的相似度。剩余的样品多样性较高,拥有最高的香浓-微纳指数2.91。典型相关分析CCA的结果表明微生物的多样性组成与理化因子有密切的关系,如水的p H以及Hg2＋、Pb2＋、Cl-、SO2-4、Fe3＋的含量。     

Response of soil fungal community to long-term chromium contamination

To further study the fungal community in heavy metal contaminated ecosystems, soil samples were collected from an abandoned chromium (Cr) factory, and fungal community was analyzed by Illumina sequencing of Internal Transcribed Spacer (ITS) amplicons. The results showed that Cr contamination changed the composition and structure of soil fungal community, but didn't change the diversity. Fungus showed various responses to Cr contamination. LEfSe analysis revealed that the biomarker changed a lot in the Cr-contaminated samples in comparison with that in the control samples. The changes in fungal community may be caused by the direct toxic effects on fungi by high concentration of Cr and the significant change in soil properties resulting from Cr contamination. Among all the Cr fractions, organic matter-bound Cr and exchangeable Cr showed significant effects on the fungal community and organic matter also showed a significant effect on soil fungal community.     

Heavy metals contamination characteristics in soil of different mining activity zones

Depending upon the polluted features of various mining activities in a typical nonferrous metal mine, the contaminated soil area was divided into four zones which were polluted by tailings, mine drainage, dust deposition in wind and spreading minerals during vehicle transportation, respectively. In each zone, soil samples were collected. Total 28 soil samples were dug and analyzed by ICP-AES and other relevant methods. The results indicate that the average contents of Zn, Pb, Cd, Cu and As in soils are 508.6, 384.8, 7.53, 356 and 44.6 mg/kg, respectively. But the contents of heavy metals in different zone have distinct differences. The proportion of oxidizing association with organic substance is small. Difference of the association of heavy metals is small in different polluted zones.     

德兴铜矿尾矿库重金属的浸出

德兴铜矿的4#尾矿库废水来源包括碱性浮选矿浆和附近露天矿山的酸性废水（AMD）。因此,酸性矿山废水的酸化作用极可能造成尾矿中重金属的浸出。通过实验室的批次实验对德兴铜矿尾矿中锌、铜、铁和锰的浸出行为进行了研究,对pH值、温度、颗粒大小和接触时间对重金属浸出的影响进行了讨论。结果表明,锌、铜、铁和锰是尾矿中的主要重金属,石英类脉石矿物是尾矿的主要成分。尾矿的溶解反应受酸度控制,其动力学可以根据非均相反应的模型来表达,通过表面化学反应作为速率决定步骤的核收缩模型来解释。这些重金属的浸出依赖于pH值和接触时间。批次实验研究得出,锌、铜、铁和锰在pH=2．0时的最大浸出率分别为5．4％、5．8％、11．1％和34．1％。重金属的溶出与温度呈正相关性。颗粒大小不会改变这些重金属的浸出趋势,但会略微导致重金属的最高浓度和平均水平的下降。     

Pollution hazards of heavy metals in sewage sludge from four wastewater treatment plants in Nanchang,China

The pollution hazards of heavy metals were investigated in sewage sludge collected from four wastewater treatment plants in Nanchang City, China, including Honggutan (HGT), Chaoyang (CY), Qingshanhu (QSH) and Xianghu (XH). Contamination/risk characteristics of heavy metals (Cu, Pb, Zn, Cd, Cr and Ni) were evaluated based on their leachable content, total content and chemical speciation. The sewage sludge from QSH contained higher total contents of heavy metals (except Pb) than those from HGT, XH and CY. The total contents of Cd and Ni were mostly beyond standard. Cu, Cr and Pb were predominantly present in potential effect and stable fractions. Zn and Ni showed higher bioavailability. Cd presented roughly uniform distribution into four fractions. The leaching contents of heavy metals almost exceeded the threshold values, especially for Zn and Ni. The potential ecological risk indexes of heavy metals in sewage sludge were 4263.34–7480.26, indicating very high risks. Cd contamination is the major concern.     

广州市不同来源污泥中重金属的含量和形态分布特征

采集了广州市4个不同来源污水处理厂及1个工业废水处理厂的脱水污泥,分析污泥的理化性质参数和重金属(Zn、Cu、Pb、Cr、Ni、Mn、Cd)的含量,重点利用BCR法研究不同污泥中重金属的赋存形态。结果表明,脱水污泥中有机质含量较高,并且富含N和P营养成分。污泥中重金属含量差别较大,其中Mn、Zn、Cu含量高,其次是Ni、Pb、Cr,Cd含量最低,但5个不同来源污泥中重金属的含量都高出广州市农田背景值。除了S1污水污泥中的Cu、Cd及S1、S2、S5污水污泥中的Ni外,其他污泥中重金属的含量都低于国家污泥农用控制标准(GB 18918-2002)。BCR连续提取法表明,污泥中的Mn和Zn主要以酸可交换态及易还原态存在,Cu和Cr主要以可氧化态和残渣态存在,Pb大部分存在于残渣态,Ni和Cd的形态分布没有明显特征。     

Cu behaviors and effects of mine drainage in Kosaka River,Hokuroku mining district,Northeast Japan

Focusing on the origin of the heavy metal, this study aims to build an imputed method to estimate the heavy metal content in river water by making a distinction between the heavy metal of natural origins and that caused by human activities. Supported by GIS, Kosaka watershed within the Hokuroku basin was divided into several sub-watershed polygons and the outflows of water and Cu were calculated for each polygon. Compared with the natural origin, the dominant Cu emissions affected the river water more significantly in local. Based on the mass balance closure, the heavy metal content of Cu in the Kosaka River was estimated by the conflux accumulation of tributaries and mine drainages. The estimated Cu concentrations were checked by comparing with the actually measured values at monitoring points along the Kosaka River and the results are coincidence with each other in general. It is revealed that the mainstream water quality could be estimated by seizing the water quality of upstream tributaries and human drainages.