Chemical Fractionation and Contamination Intensity of Trace Elements in Stream Sediments at the Sarcheshmeh Porphyry Copper Mine, SE Iran

This paper presents chemical fractionation and contamination intensities of trace elements in stream sediments at the Sarcheshmeh mine, southeastern Iran, which is one of the world’s largest Oligo-Miocene porphyry copper deposits. Evaluation of environmental pollution indices and maximum probable background concentrations revealed that As, Cu, Cd, Mo, Pb, Sb, Se, S, and Zn are highly concentrated in the contaminated sediments, while Cr, Co, Ni, Fe, and Mn show lower enrichment values. Discharges of industrial effluents (especially those contaminated by tailings), reject waste from the semi-autogenous mill, and rock waste drainages are the main anthropogenic contaminant sources. High values of As, Cu, Fe, Mo, Pb, and Zn were associated with the oxidizable, primary sulfide, and residual sediment fractions. Relatively high percentages of Co (>92?%), Cr (>58?%), Cu (>79?%), Fe (>40?%), Mn (>97?%), Ni (>87?%), and Zn (>83?%) in the sediments associated with the rock waste drainages were readily released during the extraction of water-soluble, exchangeable, and carbonate fractions. Sediments that received reject waste drainages were also polluted by As (>351.7?mg?kg^?1), Cu (>1.58?%), Mo (>91.8?mg?kg^?1), Pb (>291.8?mg?kg^?1), and Zn (>762.4?mg?kg^?1). A large percentage of these contaminants were found to be adsorbed and co-precipitated with amorphous Fe-oxides and carbonate phases. The chemical fractionation pattern of the potentially hazardous trace elements corresponded well with the mineralogical composition of the contaminated sediments.     

Lime Treatment of Mine Drainage at the Sarcheshmeh Porphyry Copper Mine,Iran

Laboratory and field treatment tests were performed to evaluate the effectiveness of lime treatment for mitigation of environmental effects of acid mine drainage (AMD) at the Sarcheshmeh porphyry copper mine. AMD associated with the rock waste dumps is contaminated with Al (>36,215 μg/L), Cd (>105 μg/L), Co (>522 μg/L), Cu (>53,250 μg/L), Mn (>42,365 μg/L), Ni (>629 μg/L), and Zn (>12,470 μg/L). The concentrations of other metals (Fe, Mo, Pb, and Se) are low or below detection limits (As, Cr, and Sb). Due to the very high Al and Mn content and the low concentration of Fe, a two-stage lime treatment method was chosen for the laboratory tests. In the first stage, the AMD was treated at four pH set points: 7.5, 8.9, 9, and 10. In the second stage, after removing the sludge at pH 9, treatment was continued at pH 10 and 11. The results indicated that a two-stage treatment method was not necessary because elements such as Al, Cu, Co, and Zn were easily treated at pH 7.5, while complete removal of Cd, Mn, and Ni only required a pH of 10. Increasing pH during the treatment process only caused a slight increase in Al. Field treatment tests support the laboratory results. Lime treatment of highly contaminated AMD from dump 11, using simple low density sludge pilot scale equipment, show that contaminant metals are treatable using this method. The mean treatment efficiency for contaminant metals was 99.4% for Al, % for Cd, 99.6% for Co, 99.7% for Cu, 98.5% for Mn, 99.7% for Ni, 99% for U, and 99.5% for Zn. The optimum pH for AMD treatment by lime was in the range of 9–10. The produced sludge in the treatment process was highly enriched in the contaminant metals, especially Cu (>7.34%), Al (>4.76%), Mn (>2.94%), and Zn (>1.25%). A correlation coefficient matrix indicates that the distribution pattern of the contaminant metals between soluble and precipitated phases is consistent with the hydrochemical behavior of the metals during the lime treatment process.     

Spatial Attenuation of Mining/Smelting-Derived Metal Pollution in Sediments From Tributaries of the Upper Han River,China

Spatial variations in contaminant distribution in river sediments are useful for pollutant diagnosis. This study investigated 18 metals/metalloids (Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Sn, Tl, U, V, Zn, and Hg) in sediments of rivers impacted by Sb and Hg mining/smelting activities in headwater catchments of the Han River Basin, China. Source and pollution assessments of the metals were examined based on their spatial variations. The results showed that sediment concentrations of Cu, Cr, Tl, U, Pb and typically, Ag, Mo, Sb, and Hg were generally elevated. However, their concentrations decreased from upstream to downstream along the river gradient. By combining their spatial variations with the results of multivariate analyses, it was deduced that the elevated concentrations were due to mining/smelting activities. At downstream sites, all elevated concentrations decreased to near background levels, except for those of Hg and Sb. The maximum concentrations of Hg and Sb in the river sediments, which were two- to three-orders of magnitude higher than the reference values, are still considered to pose very high potential ecological risks.

     

山东省博山区土壤元素分布特征研究

通过对山东省博山区土壤元素背景值状况的计算和研究,统计N、I、V、F、Cd、Cr、Hg、Co、K、P、Mn、Mo、Ni、B、Pb、As、Cu、Se、Zn、Ge、Sb、Fe、有机质等28种指标的表层土壤地球化学特征参数,查明了土壤元素分布特征、富集贫化规律,对其与全国、全省同类参数的差异进行了分析。结果表明,含量的显著特征是高Mn、F、P、Sr,而低Hg;大部分元素在表层土壤中的含量继承了土壤母质的成分特征,但Cd、Cr、Hg等受人为活动和污染源的作用在表层土壤中明显富集。区内土壤环境质量水平总体较好,部分重金属元素分布受地质背景控制,污染地块面积小。研究区Se、Zn、Ge等元素丰富,特色土地资源具有良好的开发前景。     

Heavy Metal Pollution Assessment in Surface Water Bodies and its Suitability for Irrigation around the Neyevli Lignite Mines and Associated Industrial Complex, Tamil Nadu, India

Opencast lignite mines, pit-head thermal power plants, and other associated industries in the Neyveli mining and industrial complex generate huge quantities of solid and liquid wastes that are contaminated with heavy metals. Some of these are toxic or carcinogenic at sufficient concentrations. Copper, Zn, Mn, Fe, Ni, Cd, Cr, Co, Pb, and Hg concentrations in surface water in the study area are from 2 to 1200 times higher than average concentrations in river water worldwide. Heavy metal contamination in the natural reservoirs (Peria, Kolakudi, Walaza, and Perumal Ponds, and the Paravannar River) is mainly due to the discharge of untreated mine water, fly-ash pond water, and effluents from associated industries. These waters have long been used for bathing, washing, animal watering, etc. Untreated mine and industrial waste water, and natural reservoir water have been used by nearby villagers for irrigation for the last four decades, which may have led to deterioration of soils, surface water, and groundwater. Heavy metal analyses of mine water, fly-ash pond and industrial effluents and the natural reservoirs reveals that Co, Cr, and Hg are above the recommended irrigation water quality standards in 17%, 75%, and 100% of the samples, respectively. Most samples were within the permissible limits for Mn, Ni, and Fe, while Pb, Zn, Cd, and Cu were within the limits in all samples. At elevated concentrations, toxic metals like Cr, Co, and Hg can accumulate in soils and enter the food chain, leading to serious health hazards and threatening the long-term sustainability of the local ecosystem.     

南非煤有害微量元素在干法分选中的迁移特性

 摘要：论文以南非煤的空气重介质流化床干法分选为研究对象,对其在干法分选中有害微量元素的迁移特性进行了探索,分析了As、Ba、Cd、Co、Cr、Cu、Hg、Mn、Ni、Pb、Sb、Se、Zn等在不同粒级产品中的分配情况,从而研究了干法分选对煤中有害微量元素的脱除效果。实验结果表明,对南非煤进行干法分选可以有效地脱除其中的有害微量元素,其中Cr、Cu的脱除率超过50%,As、Mn的脱除率接近50%,Co的脱除率高达39%。空气重介质流化床干法分选可以作为南非的一种经济、高效的煤中有害微量元素燃前控污手段。     

废弃矿区土壤重金属污染程度及生态风险评价研究

采用内梅罗指数法、地累积指数法对废弃矿区土壤重金属污染程度进行分析,并用潜在生态危害指数评价生态危害情况。研究结果表明,内梅罗指数法筛选Zn、Pb、Cd、As是主要污染因子,综合污染指数分别为16.30、9.48、20.16和7.07,属于重度污染;除点位11、12和14以外,其他11个点位的污染程度均为重度污染。地累积指数法筛选出Zn、Pb、Cd三种元素,未污染的元素为Ni、Hg、Cr、Ag,主要的污染点位是点位1、2、3。潜在生态危害指数法评价结果表明,主要污染因子为Cd、Hg两种元素,轻度污染的元素为Zn、Pb、Cu、As、Ni、Cr,主要的污染点位是点位1、2、3。     

煤炭洗选中有害痕量元素的迁移与脱除

对3个大型洗煤厂的原煤和相应的洗选产物进行了现场采样分析,通过测定原煤和各洗选产物中痕量元素的含量,研究了As,Be,Cd,Co,Cr,Hg,Mn,Ni,Pb,Sb和Se等11种有害痕量元素在洗煤过程中的迁移与脱除规律。结果表明,常规物理洗选能有效脱除煤中的无机矿物组分,在降低精煤灰分和硫分含量的同时,精煤中有害痕量元素也得到一定的脱除,除Se的脱除率较低以外(13.3%),其他元素的脱除率都在20%以上,这主要是由于这些痕量元素随着伴生的无机矿物被脱除;洗选后Be,Cd,Co,Cr,Hg,Mn,Ni主要向矸石中富集,Se则主要在中煤里富集,As,Pb和Sb在不同洗选产物中的分布则较为复杂。     

皖北煤矿区农田土壤-小麦中重金属分布特征 及健康风险评价

为了研究矿区农田土壤-小麦中重金属分布及农作物中重金属的迁移特征,以皖北恒源煤矿为研究对象,在矿区范围内采集了16个农田土壤和对应的小麦样品进行测试分析,应用内梅罗指数法评价了矿区内农田土壤重金属的污染状况,采用回归模型分析研究土壤根系、根系茎籽粒中重金属的迁移转化,并利用靶标危害系数法评价了小麦籽粒中重金属对人身健康的影响。研究结果表明:研究区农田土壤中的Cu、Zn、Mn、Pb、Hg、Cd、As、Cr和Ni等8种重金属元素含量低;小麦籽粒中重金属含量也未超出标准限量值;在小麦根、茎、籽粒等器官中,Mn、Pb、Cd、As、Cr和Ni在小麦根部含量最大,Hg较多地分布在小麦的茎中,Zn和Cu更易向上迁移至小麦的籽粒中;小麦籽粒中的Pb、Hg、Cd、As和Cr等重金属的单一重金属元素的靶标危害系数THQ和多种重金属元素的复合危害系数TTHQ均小于1。     

某工业废渣堆放场地重金属污染特征与健康风险评估

以某工业废渣堆积场为例,探讨了该场地废渣、土壤和地下水中重金属污染特征,着重评估了重金属污染对人体的致癌风险和危害商值。结果表明:1)场地废渣中8种重金属(As、Cu、Ni、Zn、Cd、Pb、Cr、Hg)均有不同程度超标,其中As污染范围最大(超标率达91%),Cr存在高污染集中区,土壤中Cu、Ni、Zn和Cd浓度超出当地背景值,地下水中As和Ni也存在超标现象;2)废渣和土壤中的As、Ni和Cr三种重金属的致癌风险水平均超过了致癌风险可接受水平(1.0×10^-6),其中Cr的致癌风险最高,高达5.3×10^-3,相同金属元素废渣的致癌风险值大于其在土壤中的风险值;3)废渣中As、Cr和Cd的危害商值大于其可接受水平(1),其中Cr的危害商值最大(高达7.5),土壤中重金属的危害商值基本在可接受范围(除As外);4)三种暴露途径按贡献率从大到小依次为:经口摄入>吸入土壤颗粒物>皮肤接触。     

中国西北某煤化工区土壤中重金属污染特征及其源解析

为明确煤化工区内土壤中重金属的污染状况及其来源,本文选定我国西北某大型煤化工区的土壤样品、原煤样品和煤灰样品,通过消解后应用ICP-MS和冷原子吸收等方法对样品中Cr、Cd、As、Pb、Ni、Se、Hg等8种元素含量进行测定。选用富集因子法、相关系数分析法、聚类分析法和因子分析法等数学方法,对煤化工区土壤中的重金属进行污染评价和来源解析。结果表明:Cr、As、Se、Ag、Cd属于人为源,依据数据模型以及土壤、煤和煤灰中重金属迁移规律分析,推定区域内土壤重金属来源主要有三种污染源。其中,煤气化污染源主要负载Se、Cd、Pb,其对区域土壤中重金属的总贡献率为32.01%;渣场扬尘等主要负载Cr、Ag和Hg,对区域内土壤中重金属的总贡献率为23.89%;交通等外来污染源主要负载As、Ni等,对区域内土壤中重金属的总贡献率为19.61%。     

燃煤电厂中有害微量元素迁移释放

对两个电厂的原煤、底灰、飞灰和超细飞灰（≤10 μm）进行了有害微量元素含量的测定,研究了As、Cd、Cr、Pb、Se、Mo、Ni、Be、Cu、Th、U、V、Zn、Hg等14种元素在煤燃烧过程中的散逸、迁移行为,揭示了它们在燃煤过程中在气态产物和固态产物（底灰、飞灰、超细飞灰）中的分配富集特征,分析了这些元素的环境效应。结果表明：在两电厂中,元素Cd、Pb、Zn富集系数由大到小为超细飞灰>飞灰>底灰;As的分布特性与煤中Ca的含量密切相关;较低的烟气温度能够使部分气态Hg在飞灰颗粒上发生凝结;将几种元素分为3类：Ⅰ类,留在固体废物中的元素V（QR＞085）;Ⅱ类,部分留在固体废物中的元素As、Cd、Cr、Pb、Se、Mo、Ni、Be、Cu、Th、U、Zn（0.85≥QR＞010）,其中As、Cr、Ni、Be、Cu、Th的富集程度较强,Zn、Mo、Se、Cd较弱;Ⅲ类,主要挥发到大气中的元素Hg（QR接近0）。     

模糊数学法综合评价土壤重金属污染程度研究

为了评价土壤中重金属污染程度,采用模糊数学法研究了最大隶属度、污染程度等,评价结果表明:研究区域土壤Zn、Pb、Cu、Cd、As、Hg、Ni和Cr最大值浓度超出背景值16.25、14.87、4.76、9.79、10.70、11.68、1.22和1.06倍,土壤受到Zn、Pb、Cu、Cd、As和Hg六种重金属元素的污染;模糊数学法综合评价重金属元素的最大隶属度为0.472,污染程度为三级污染。     

基于数理统计分析的淮南煤中微量元素的研究

采用高分辨率电感耦合等离子质谱仪测定了淮南矿区煤中10种微量元素含量。结果表明:淮南煤中Co、Ni、Th、Zn和Cd低于全国均值,没有异常富集;Mo、Sb、U略高于全国均值,Ba和Cr平均含量明显高于中国煤中均值,可能有异常富集。运用相关分析、R型聚类分析和因子分析等数理统计方法,对淮南矿区微量元素与灰分的相关性及赋存状态进行了分析。结果表明:元素Cr、Ni、U、Th和Ba与灰分线性正相关,其中Th和Ba与灰分高度正相关,其他元素与灰分无法建立线性关系;煤中Th、Ba、Ni、Cr、U和Co可能主要以无机态赋存于煤中;Zn和Cd可能以闪锌矿等硫化物微粒的形式赋存于有机质中;Mo和Sb赋存状态较为复杂,尚需进一步研究。     

Assessment of Metals Pollution from Tailing Sites in the North Caucuses Region,Russia

The concentrations of metals were determined in the water and bottom sediments of both the Urup and Kuban Rivers near tailings sites in the North Caucasus region of southern Russia. The average concentrations in the Urup followed the order Fe?>?Mn?>?Pb?>?Cu?>?Zn?>?Cd?>?Ni?>?Co, while in the Kuban, the order was Fe?>?Pb?>?Zn?>?Ni?>?Mn?>?Cd, with copper and cobalt not detected. The levels of Zn, Cu, Pb, Cd, and Ni were above Russia’s maximum permissible concentration in both rivers. The water pollution index (WPI) values in Urup ranged from 12.97 to 28.17, indicating that the river is extremely polluted (Class VII), while the WPI value for Kuban ranged from 2.34 to 4.33 downstream of the tailings site, which corresponds to Class IV (contaminated). Calculating the coefficient of accumulation in sediments (CAS) revealed that in Urup, the CAS values for Ni and Cu were 3046 and 11638, respectively, which indicates an emergency environmental situation, while for Co, Fe, and Mn, the situation is high level chronic pollution (CAS?>?10⁴). The Kuban CAS values of Fe and Mn were also >?10⁴, again highly and chronically polluted. Most of the metals in both rivers are bound to the sediments, with minimal mobility. The potential ecological risk is moderate to considerable in Urup, and low in the Kuban River.     

某钒尾矿库周边土壤重金属污染评价

为定量评价钒尾矿库周边土壤重金属污染程度,采用地累积指数法、内梅罗指数法、潜在生态危害指数等3种方法结合进行土壤重金属污染综合评价。结果表明,尾矿库周边土壤存在重金属Cd、Ni、As、Cr、Cu、Zn、Pb含量积累和超标情况,Cd的超标率最大,Ni、As 次之。总体上,尾矿库周边土壤中Cd为主要污染因子,其次为Ni、As,其它重金属元素贡献较小。生态风险评价表明,Cd、Ni为主要生态危害元素,Cd以较高风险为主,Ni为中度风险。该钒尾矿库对周边土壤的影响不容忽视,应加强重金属污染的污染防治。     

兖州矿区表层土壤重金属污染基线模型的建立

以Sc(钪)作为标准化元素,在采集、测试、分析兖州矿区表层土壤样品的基础上,研究了该区内表层土壤中As (砷)、Cd(镉)、Co(钴)、Cr(铬)、Cu(铜)、Hg(汞)、Mn(锰)、Ni(镍)、Pb(铅)、Zn(锌) 重金属污染元素的环境地球化学特征,采用标准化方法分别建立了这10种重金属元素的环境地球化学基线模型.     

SPSS在淮南矿区煤中微量元素研究中的应用

在研究煤中微量元素的过程中,SPSS具有较强的适用性。文章以淮南矿区煤中微量元素的研究为例,详细介绍了SPSS在统计学描述、正态分布P-P检验、回归和相关分析、聚类分析和因子分析等方面的应用。分析结果表明:煤中Cr元素服从正态分布;Zn、Cd、Pb和Mo与硫分呈正相关;Ni、Cu、Co和Mo可能赋存于黄铁矿中;Be、Se和Cr与有机质缔合;Zn、Pb和Cd最可能以闪锌矿形式赋存。     

Risk Assessment and Ranking of Metals Using FDAHP and TOPSIS

The sediment of the Sarcheshmeh copper mine in Iran contains high concentrations of trace metals. In this risk assessment study, criteria such as contamination factor, pollution load index, and geoaccumulation index were used to assess levels of Co, Cu, Mo, Zn, Cr, Mn, Ni, Pb, Ti, and Fe in the mine sediment released to the tailings dam. Expert opinions on the relative importance of each of the indicators were used to assign a final weighting of the criteria using the fuzzy Delphi analytic hierarchy process, and the metals in the sediments of the study area were ranked and clustered using the TOPSIS method. Based on the results, the metals were clustered into 10 categories with copper, iron, and zinc having the highest pollution and critical risk.     

煤中有害微量元素的洗选迁移特性

应用浮沉试验和分步释放浮选试验对贵州省水城煤业集团大河边矿原煤进行了洗选分离,采用电感耦合等离子体质谱(ICP-MS)测定了原煤和11个洗选产品中As,Se,Cd,Pb,Be,Cr,Co,Mo,Cu,Zn,Ni,V,Sb,Mn,Th,U等潜在有害微量元素的含量,应用等离子体低温灰化分离出原煤和洗选产品中的无机矿物质。结果表明,原煤中微量元素的总体含量水平中等;在浮沉试验中密度越高的洗选产品中微量元素的含量越高;在分步释放浮选试验中,精煤中微量元素的含量最低,尾煤中微量元素的含量最高,在中间产品中呈过渡关系;绝大多数微量元素与矿物质总量之间都存在极高的相关性,表明微量元素在煤中主要以无机态赋存,其迁移特性主要受控于煤中的矿物质。