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1 IntroductionThegoldindustryinChinagrowsupquicklywiththegrowthrateofabout 10 %since 90’s.In 1995,theproductionofgoldwasover10 0tons/a,andin 1996reached 12 0tons/a .Itisrankedsixthintheworld(Chang ,1995) .Theirmainproceduresofgoldextractionare :(1)cyanizationintotalore carbo… 相似文献
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GUAN Ming ZHENG De |ming YU Ya |qin ZHAO Jie |xu BI Wen |xiang WU Di LING Jing DU Wei XIA Yu |Yong GAO Shen SUN Wei |wei GUAN Ci |nan WANG Yan |li 《环境科学学报(英文版)》2000,(Z1)
Inrecentyears,mercurycontaminationhasbeen paid greatattentiontoovertheworld(Zilloux ,1993;Monamy ,1993;Guan ,1994;Yang ,1992 ;Li,1993;1994;SCOPE ,1994) .TheprincipalfocusistodecreaseHgcontaminationinordertoprotecttheecosystemenvironmentandthehuman’shealth .Itisdifferentfrom“mi… 相似文献
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Mercury (Hg) concentrations in sediment samples collected from the inner and middle shelves of the East China Sea (ECS) were analyzed to evaluate Hg contamination levels and to calculate Hg sedimentation rates and total accumulation in the ECS. The range of Hg concentrations in surface sediments of the inner shelf was 26.5–47.6 ng/g, and that for the middle shelf was 4.1–13.9 ng/g. Hg concentrations correlated well with organic carbon contents but varied inversely with sediment grain size. Enrichment factors indicated that the whole inner shelf and a small portion of the middle shelf were slightly contaminated by Hg. Hg accumulation rates in the ECS ranged between 0.42–48.7 ng/(cm2·yr), with higher values observed in the inner shelf. Total Hg accumulation in the calculated area (accounting for 80% of the ECS continental shelf area) ranged from 25 to 30 tons/yr; approximately 51% and 17% of the accumulated Hg mass was deposited in the Yangtze estuarine zone and the inner shelf, respectively. 相似文献
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The mining of gold has been and continues to be an important aspect of Australian industry. Gold mining moved quickly from fossicking and alluvial sources in the 1850's to hard rock mining. This paper presents, arguably for the first time, a detailed historical compilation of Australian gold mining production data. This data is then analysed in the context of sustainability, focussing particularly on mineral resource sustainability and the broader aspects of environmental impacts now commonly reported by some mining companies in annual sustainability performance reports. The key trends which are demonstrated by the data include a long-term decline in ore grade, increased open cut mining, substantive increases in tailings and waste rock production, as well as showing the impact of new technologies and economics on available gold resources. The available environmental data on material and energy inputs to and pollutant emissions from gold production is also presented, showing a clear sensitivity to ore grade. In terms of sustainability, these relationships raise significant issues such as increasing greenhouse footprint per unit gold produced, potential impacts on energy and water consumption, as well as overall gold resource sustainability. The paper presents a unique case study of the resource and environmental sustainability of the Australian gold mining sector with major implications for sustainability policy and reporting. 相似文献
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Carlos E. Rodr′?guez-Rodr′?guez Evelyn Rodr′?guez Rigoberto Blanco Ivannia Cordero Daniel Segura 《环境科学学报(英文版)》2010,22(10):1595-1601
Because of the lack of reports, the base levels of microbial contamination on stored fuels are unknown in tropical regions and it is
unclear whether these levels have some influence on fuel quality parameters. Therefore, fungal quality in automobile fuels stored across
Costa Rican territory was evaluated during two years according to the standard ASTM D6974-04. For a total of 96 samples, counts and
identification of molds and yeasts were performed on regular gas, premium gas and diesel taken from the bottom and superior part of
the container tanks. The highest contamination was found on the bottom of the tanks, where an aqueous phase was usually identified,
showing populations over the ones present in the hydrocarbon itself (up to 108 CFU/L). Diesel was the most contaminated fuel (up to
107 CFU/L); however, an alteration on the physicochemical parameters was not observed in any kind of fuel. Seventy-five mold strains
were isolated, Penicillium sp. being the most common genus (45.8% of the samples), and ten yeast strains, from the genera Candida sp.
and Rhodotorula sp. Four of the yeasts were able to grow on diesel as the sole carbon source, at concentrations ranging from 0.5% to
25%. Increasing the frequency of tank cleaning, adding antimicrobial agents and monitoring microbial populations are recommended
strategies to improve microbial quality of stored fuels. 相似文献
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松花江上游金矿开采区环境中汞污染的空间分布特征 总被引:3,自引:2,他引:3
采用俄罗斯Lumex公司生产的RA-915+汞自动分析仪采集松花江上游桦甸金矿开采区环境中的气态总汞,并同步采集水体、土壤和植物样品,测定各环境要素中的汞含量,旨在研究金矿开采区周围大气汞的分布特征、影响因素及其与其它环境要素的相关性.结果表明,环境中大气汞污染的时间分布规律为夏季大于秋季,傍晚高于午间;空间分布规律以金矿开采和汞源为中心随距离加大而逐渐衰减;金矿开采区附近环境要素中汞污染的规律为:沉积物土壤植物水,植物中总汞污染特征为:根茎叶,秋季植物中汞的含量普遍大于夏季,这与植物随生长发育不断通过土壤向体内富集污染元素有关.无论夏季还是秋季,气汞与植物根部的相关性均最高,分别为0.83和0.97. 相似文献
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IntroductionHealthhazardsfrommercuryintheenvironmenthavecausedrestrictionsintheuseofmercuryandastrictercontrolofthereleaseofmercuryfromindustrialandotheruses.Butatthesametimethesesourcesofmercuryhavebeensubjectedtoregulation ,twonewsourceshaveappeared … 相似文献
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珠江河口沉积物Hg的分布与污染评价 总被引:2,自引:0,他引:2
利用Hg元素直测仪分析了珠江河口表层沉积物和柱状沉积物Hg的含量和背景值.沉积物Hg的背景值为(45.94~70.62)×10-9.表层沉积物Hg含量在(20.81~369.20)×10-9,平均为168.23×10-9,平面分布呈西部向东部和东南方向减少的趋势,其中,以西部浅滩沉积物Hg含量最高,富集程度最大.柱状沉积物Hg含量在(33.61~250.43)×10-9,平均含量150.49×10-9,垂直分布存在显著的地域差异,东滩沉积物Hg表现为上部富集,而西滩沉积物表现为均匀分布.地质累积指数法、潜在生态危害指数法和单因子污染指数法三种污染评价的结果表明,珠江河口表层沉积物的Hg污染区主要集中于西部浅滩,存在中等程度的Hg污染. 相似文献
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Seepage from Hg mine wastes and calcines contains high concentrations of mercury (Hg). Hg pollution is a major environmental
problem in areas with abandoned mercury mines and retorting units. This study evaluates factors, especially the hydrological and
sedimentary variables, governing temporal and spatial variation in levels and state of mercury in streams impacted by Hg contaminated
runo . Samples were taken during di erent flow regimes in theWanshan Hg mining area in Guizhou Province, China. In its headwaters
the sampled streams/rivers pass by several mine wastes and calcines with high concentration of Hg. Seepage causes serious Hg
contamination to the downstream area. Concentrations of Hg in water samples showed significant seasonal variations. Periods of
higher flow showed high concentrations of total Hg (THg) in water due to more particles being re-suspended and transported. The
concentrations of major anions (e.g., Cl??, F??, NO3?? and SO4
2??) were lower during higher flow due to dilution. Due to both sedimentation
of particles and dilution from tributaries the concentration of THg decreased from 2100 ng/L to background levels (< 50 ng/L) within
10 km distance downstream. Sedimentation is the main reason for the fast decrease of the concentration, it accounts for 69% and 60%
for higher flow and lower flow regimes respectively in the upper part of the stream. Speciation calculation of the dissolved Hg fraction
(DHg) (using Visual MINTEQ) showed that Hg(OH)2 associated with dissolved organic matter is the main form of Hg in dissolved
phase in surface waters in Wanshan (over 95%). 相似文献
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松花江上游夹皮沟金矿土壤与大气汞污染特征 总被引:2,自引:3,他引:2
在松花江上游夹皮沟金矿开采区内,混汞法提金工艺已使用180余年,导致严重的环境介质汞污染问题.为研究土壤和大气汞污染特征,使用塞曼效应汞分析仪(Zeeman RA915+)测定了大气汞含量,使用冷原子吸收分光光度法(GB/T17136-1997)测定了土壤汞含量,使用动态通量箱法测定了老金厂、二道沟、二道岔和夹皮沟镇小区四处土/气间汞交换通量;对土壤汞含量和大气汞含量进行了线性回归分析;并对土/气间汞交换通量与气象因子进行了相关性分析.结果表明:①区域大气汞含量均值为(71.08±38.22)ng.m-3.②区域土壤汞含量均值为(0.913 1±0.040 8)mg.kg-1;土壤汞含量与大气汞含量显著正相关.③各采样点土/气间汞交换通量为:老金厂(129.13±496.07)ng.(m2.h)-1,二道沟(98.64±43.96)ng.(m2.h)-1,二道岔(23.17±171.23)ng.(m2.h)-1,夹皮沟镇小区(7.12±46.33)ng.(m2.h)-1.④太阳辐射是老金厂、二道岔和夹皮沟镇小区土/气间汞交换通量主要影响因子,太阳辐射、大气温度和土壤温度共同控制二道沟土/气汞交换通量过程;地形条件的干扰,形成三类迥异的土/气间汞交换通量日变化特征形态. 相似文献
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利用高时间分辨率自动测汞仪(Tekran 2537B)于2017年6月~2018年5月对武夷山气态元素汞(GEM)进行了连续1a的观测.结果表明,武夷山GEM年均浓度为(1.70±0.43)ng/m3,稍高于北半球背景值,表明武夷山受到一定程度的大气汞污染.GEM浓度表现为冬季>秋季>春季>夏季,季风和风速是影响武夷山GEM季节变化的主要因素.武夷山四季GEM表现为不同的日变化特征,早上8:00之后,春秋季GEM继续呈现下降趋势,其他季节则呈现先升后降再上升,并在晚上不同时刻出现峰值.GEM值白天低于晚上,这与风速和汞的长距离迁移有关.后向轨迹和浓度权重轨迹分析结果表明,偏西风背景下污染气团经江西向武夷山输送是大气汞迁移的主要路径,而江西和福建中北部为武夷山大气汞污染的潜在源区.△GEM/△CO值表明武夷山GEM汞污染主要来源于人为工业排放,生物质燃烧贡献较弱. 相似文献
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中国水环境微塑料污染现状及其潜在生态风险 总被引:2,自引:0,他引:2
微塑料在水环境中的广泛存在导致的环境污染问题引起了全世界的关注.微塑料对水生生物的生长活动、生命健康产生威胁,同时也对生态系统的功能产生影响.中国是世界上十大塑料制品生产和消费国之一,近年来,我国在多个水环境中发现了微塑料的踪迹.本文对中国几种水环境(污水处理厂、淡水、海洋)中微塑料的污染情况进行了总结,并对微塑料产生的影响,特别是微塑料产生的潜在生态风险进行了介绍.现阶段水环境中微塑料的研究大多数是针对于某一特定水域,缺少微塑料在不同水域环境中迁移赋存的探究,且对于微塑料生态毒性的研究还很少,为此我们提出了未来水环境中针对微塑料研究的建议与展望. 相似文献
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大气汞沉降是汞从排放源进入地表系统最主要的迁移途径,利用汞同位素追踪汞在大气中的迁移转化规律及潜在来源对研究汞的生物地球化学循环具有重要意义.本研究于2012—2013年对厦门市小坪、坂头、鼓浪屿和洪文站点降水中总汞(THg)浓度和汞同位素的变化特征进行了研究.结果表明,厦门降水中THg浓度为1.0~59.4 ng·L~(-1),大气THg湿沉降量为13.1μg·m~(-2)·a~(-1).厦门冷、暖季降水中THg浓度相当,但由于暖季丰沛的降水量,导致暖季THg的湿沉降量约为冷季的2.5倍.降水样品中均表现出负的偶数汞同位素质量分馏(δ~(202)Hg,-2.2‰~-1.5‰)、正的奇数汞同位素非质量分馏(Δ~(199)Hg,0.08‰~0.22‰),以及轻微偏正的偶数汞同位素非质量分馏(Δ~(200)Hg,0.01‰~0.07‰).厦门降水中奇数汞同位素非质量分馏是大气汞液相光致还原反应的结果.偶数汞同位素非质量分馏不明显与其处于较低的纬度有关.厦门降水中δ~(202)Hg接近于厦门当地及贵州燃煤烟气中的δ~(202)Hg值,表明厦门降水中汞可能受到本地或传输过来的燃煤排放的影响. 相似文献
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植被主要通过叶片气孔吸收大气气态单质汞,森林植被是大气汞重要的汇.量化森林生物质汞库对了解全球汞循环至关重要.为揭示森林乔木层(乔木层分为树干、树叶、树枝、树根和树皮)、灌木层、草本层和凋落物层(凋落物层分为未分解层(Oi)、半分解层(Oe)和已分解层(Oa))汞含量和汞库分配,本研究选取黑龙江省凉水自然保护区小兴安岭原始林阔叶红松林、次生原始林云冷杉林和次生原始林白桦林3种原始林开展植物和凋落物汞含量和汞库调查.结果表明,乔木层各组织中汞含量遵循树皮 > 树叶 > 树枝 > 树根 > 树干的规律,云冷杉林乔木层汞含量总体上高于阔叶红松林及白桦林乔木层汞含量.凋落物中汞含量排序为Oa > Oe > Oi,原始林阔叶红松林凋落物汞含量高于次生原始林白桦林凋落物汞含量,但低于次生原始林云冷杉林凋落物汞含量.进一步估算生物质总汞库发现云冷杉林、阔叶红松林和白桦林分别为212、192和163 μg·m-2.乔木层地上部分是森林生物质汞库的主体,其树皮汞库占总汞库的37.4%~43.5%,灌木层和草本层仅占总汞库的1%左右.本研究可为进一步评估森林生态系统在大气汞循环中的作用及预测森林火灾发生时生物质燃烧汞释放潜势提供基础数据. 相似文献
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应用氢化物发生原子荧光光谱技术,同时测定海水养殖基地环境介质底泥、海水和水产品中微量As和Hg。研究了载流、KBH4浓度对As和Hg测定的影响。在最佳实验操作条件下,As和Hg检出限分别为0.028 3μg/L、0.017 4μg/L。底泥中As和Hg的加标回收率分别为89.7%~112.6%和91.7%~110.8%,相对标准偏差分别为2.7%~5.3%和2.2%~4.3%;海水中As和Hg的加标回收率分别为90.2%~101.8%和90.0%~108.8%,相对标准偏差分别为3.1%~5.6%和2.1%~4.5%;水产品中As和Hg的加标回收率分别为89.6%~102.0%和89.2.0%~108.0%,相对标准偏差分别为2.6%~4.9%和1.7%~4.4%。 相似文献
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Hirokatsu Akagi Koichi Haraguchi Yoshihide Kinjo Olaf Malm Fernando J. P. Branches Jeans R. J. Guimaraes 《环境科学学报(英文版)》2000,(Z1)
IntroductionSincetheearly 1980’s,rapidincreasesingoldminingactivitiesusingmercuryamalgamationtechniqueinmanydevelopingcountrieshasbeenoneofthemainsourcesofmercurypollution ,particularlyintheAmazonandothertropicalregions(Malm ,1990 ;Ramel,1996;Ikingura,1996;Lacerda,… 相似文献