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1.
黄金矿山尾矿处理,投资和工程量大,对当地生态环境破坏严重,并且损失尾矿中的已溶金,文章介绍全泥氰化矿处理新工艺,此法可以圆满解决上述问题。  相似文献   

2.
铁尾矿地砖的制备及其机理分析   总被引:2,自引:0,他引:2  
简要介绍了唐山地区铁矿尾矿制备铁尾矿砖的试验研究,并设计制备铁尾矿砖生产工艺流程和最佳配比。研究结果表明,以铁尾矿为主要材料,通过掺加适量的水泥、粉煤灰、粗骨料和一定的外加剂,经常温常压养护28天后,抗压强度可达到28.30MPa,抗折强度为5.63MPa,同时长期性能研究也表明可以制备出合格的铁尾矿地砖。为铁尾矿大量资源化利用辊供了一条新的徐径.同时还对铁尾砖的微观机理作了初步研究。  相似文献   

3.
珍珠岩尾矿烧结砖的实验研究   总被引:1,自引:0,他引:1  
以珍珠岩尾矿为原料进行烧结砖实验研究,发现该砖具有轻质、高强及保温等特点。珍珠岩尾矿烧结砖的生产,将有利于环保治理,又具有较为显著的经济效益。  相似文献   

4.
正一、概述(一)金矿尾矿的来源与特点1.来源尾矿是选矿厂在一定技术条件下,将大的矿石磨碎、磨细,从中选出有用的组分之后排放出的废弃物,也就是矿石经选别出精矿后剩余的固体废料。金矿尾矿就是在金矿开采的产物中有用组分含量较低而无法用于生产的部分。金矿尾矿按照选矿工艺的不同可以分为以下几种类型:手选尾矿、重选尾矿、浮选尾矿、化学选矿尾矿、电选及光电选矿尾矿等。随着黄金提金技术的高速发展,中国黄金矿山的数量、规模及产量也日趋增长,然而矿石入选品位却  相似文献   

5.
根据德兴矿酸性废水及尾矿分级溢流液的特性,经试验,利用尾矿分级溢流液处理矿山生废水是可行的,中和液在尾矿库进行沉淀,中和渣存放于发愤矿库内,不别建渣库,节省投资,这一处理工艺对灰似矿山具有参考价值。  相似文献   

6.
目前,我国95%以上的能源、80%以上的工业原料、70%以上的农业生产资料均来自矿产资源。随着矿产资源开采量的日益增大,矿业固体废物——尾矿的排放量也逐年增多。我国现有8000多个国营矿山和11万多个乡镇集体矿山,堆存的尾矿达40亿t以上,且每年以数亿吨的速度增加,不仅占用了大量土地,而且造成了严重的环境污染。矿山尾矿具有颗粒细、数量大、成本低的特点,除含有可回收的少量矿物成分外,基本上是由硅酸盐、碳酸盐等组成的“复合”矿物材料,是可利用的二次资源。我国制定的(中国对世纪议程冲提出:伴生资源的综合回收率2000年…  相似文献   

7.
碳酸盐岩地区矿山酸性排水的产生及其防治初探   总被引:1,自引:0,他引:1  
尾矿中的硫化物在空气、水、微生物等的作用下,发生一系列的物理化学反应,形成矿山酸性排水(AMD)。在碳酸盐岩地区,由于尾矿和围岩中都含有大量对酸具有中和效应的碳酸盐矿物,于是人们一直认为碳酸盐岩地区的尾矿不存在酸污染。而如广西大厂、广东凡口及大宝山、贵州牛角塘等碳酸盐岩地区矿山的尾矿却存在着严重的酸污染,其主要原因是碳酸盐矿物在中和酸水过程中,表面会形成阻止反应进一步进行的次生包壳,碳酸盐矿物的实际中和量达不到其理论值。矿山酸性排水携带大量的重金属离子,对碳酸盐岩地区的生态环境及矿山工程设施带来严重的危害。针对碳酸盐岩地区尾矿自身的特殊性,对新建尾矿堆采用覆盖法,而对已经产酸的尾矿用渗透反应栅法,是防治这类尾矿酸化的有效方法。  相似文献   

8.
通过实验,以金尾矿、石膏、水泥、石灰、铝粉等为原料,研究金尾矿添加量对加气混凝土性能的影响。分析认为,不同的配合比,不仅关系到产品的经济效益,还会对产品的性能有显著影响。实验得出能提高尾矿利用率的最优尾矿添加量为64.8%,最佳配比为:金尾矿64.8%、石灰16.2%、水泥14.2%、石膏4.7%、铝粉0.1%。  相似文献   

9.
对湖南湘西金矿尾矿的堆存、分布特征及其化学组成、微量元素含量等进行了初步研究.结果发现:尾矿中贵、重金属元素如Au、Sb、W、Pb、As等含量较高,因此,尾矿不仅是矿区的潜在污染源,而且是一种重要的后备资源.具有较大的二次开发前景。  相似文献   

10.
在矿石的开采过程中,不可避免的会产生尾矿,相对于其他金属而言,黄金的品位较低,开采后会产生更多的尾矿,如果没有做好相应的处理和回收利用,就会造成资源的浪费。因此,对尾矿的节能开采以及综合利用显得尤为重要。本文针对金尾矿的节能开采和综合利用技术展开探讨,将金尾矿中的有用材料进行二次回收,不仅避免了相应的浪费,还会使得土地资源得到更有效的运用。  相似文献   

11.
Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.  相似文献   

12.
A new anaerobic reactor, Jet-loop anaerobic fluidized bed (JLAFB), was designed for treating high-sulfate wastewater. The treatment characteristics, including the effect of influent COD/SO42 ratio and alkalinity and sulfide inhibition in reactors, were discussed for a JLAFB and a general anaerobic fiuidized bed (AFB) reactor used as sulfate-reducing phase and methane-producing phase, respectively, in two-phase anaerobic digestion process. The formation of granules in the two reactors was also examined. The results indicated that COD and sulfate removal had different demand of influent COD/SO4^2- ratios. When total COD removal was up to 85%, the ratio was only required up to 1.2, whereas, total sulfate removal up to 95% required it exceeding 3.0. The alkalinity in the two reactors increased linearly with the growth of influent alkalinity. Moreover, the change of influent alkalinity had no significant effect on pH and volatile fatty acids (VFA) in the two reactors. Influent alkalinity kept at 400-500 mg/L could meet the requirement of the treating process. The JLAFB reactor had great advantage in avoiding sulfide and free-H2S accumulation and toxicity inhibition on microorganisms. When sulfate loading rate was up to 8. 1 kg/(m^3.d), the sulfide and free-H2S concentrations in JLAFB reactor were 58.6 and 49.7 mg/L, respectively. Furthermore, the granules, with offwhite color, ellipse shape and diameters of 1.0-3.0 mm, could be developed in JLAFB reactor. In granules, different groups of bacteria were distributed in different layers, and some inorganic metal compounds such as Fe, Ca, Mg etc. were found.  相似文献   

13.
随着纳米技术迅猛发展,纳米颗粒的环境行为和生态效应越来越受到关注.纳米氧化物作为环境中的重要组成,广泛存在于水体、大气、土壤以及沉积物中,其大比表面积和高表面活性,控制和影响着环境中一些污染物和营养元素的形态、迁移、转化和生物有效性.纳米尺寸是纳米颗粒特有属性,颗粒尺寸大小调控和决定纳米氧化物的结构及物理化学特性,从而在较大程度上影响其与相关元素的界面反应性和环境地球化学行为.综述了纳米氧化物的尺寸对吸附、(还原)溶解、(催化)氧化、聚集和迁移等环境行为的影响,讨论了尺寸效应的作用机制,最后展望了环境中纳米金属氧化物尺寸效应有关的研究热点和方向.  相似文献   

14.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

15.
To demonstrate the existence of light thresholds in plant growth and to examine the effects of elevated CO2 on the shade tolerance of a tree species, an experiment consisting of a completely randomized design for a total of 96 yellow birch (Betula alleghaniensis Britton) seedlings was conducted with 3 light levels (2.9%, 7.7%, 26.1% of full sunlight)×2 CO2 levels (350 and 700±10 ppm) with 4 replications in a phytotron. The study proved that thresholds exist and they vary in different plant organs. In ambient CO2, the thresholds were 13.3%, 18.7%, 15.0%, 15.2%, and 15.6% of full sunlight for stem, leaf, root, total plant biomass, and the averaged value, respectively. In 700 ppm CO2, the corresponding thresholds were 16.7%, 21.3%, 18.1%, 21.7% and 19.5% for stem, leaf, root, total plant biomass, and the averaged value, respectively. The lowest threshold in the stem is an indicator of the minimal light intensity for regular growth for seedlings of this species. Below this threshold, light-stressful growth occurs. The result of a paired t-test indicated that the thresholds in elevated CO2 were significantly higher than in ambient CO2. This suggests that yellow birch will lose its moderate shade tolerance, evolutionally becoming a shade-intolerant species, and that it may become more difficult to naturally regenerate in the future.  相似文献   

16.
Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury (HgT), combinative mercury (Hgc) and gaseous mercury (HgG), and content of total organic carbon (TOC), but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of (HgG,/HgT)1992〉(HgG/HgT)1996〉〉(HgG/HgT)2000. A simple outline of Hg release in landfill could be drawn: with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants (e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum) are capable of enriching more Hg than herbaceous plants.  相似文献   

17.
This study focused on the screening of cadmium-resistant bacterial strains from Pb-Zn tailing. We investigated the diversity of microbial community inhabiting Dong-san-cha Pb-Zn tailing in Beijing, China, by polymerase chain reaction-denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene of bacterial strain, and found two dominant strains in the DGGE profile. Using special culture media, we isolated two strong cadmium-resistant bacterial strains. On the basis of morphological, physiological, and biochemical characteristics, BIOLOG, and 16S rDNA sequencing, the two strains were identified as Bacillus cereus and Enterobacter cloacae. Minimal inhibitory concentrations (MICs) of heavy metals for the bacteria were determined. E. cloacae showed higher MIC values for heavy metals and a larger range of antibiotic resistance than B. cereus.  相似文献   

18.
灭幼脲类农药对非靶生物的影响及其在生物体内的代谢   总被引:3,自引:0,他引:3  
综述国内外近年来有关灭幼脲类农药施用后对非靶生物可能造成的影响和其在生物体内吸收代谢方面的研究成果。分别阐述了施药区中,蜜蜂、家蚕、鸟类等陆生生物,鱼类、甲壳类和节肢类等水生生物可能受到的影响;以及灭幼脲类农药对家禽、家畜的影响和在它们体内的吸收代谢情况。指出,灭幼脲类农药的使用对陆生生物蜜蜂和鸟类,以及家禽、家畜等不产生明显的毒害和污染,对水生生物鱼类也没有什么影响,但对家蚕、以及水生甲壳类动物和节肢类动物(尤其是其幼体)的毒害较大。  相似文献   

19.
典型山核桃产区土壤重金属空间异质性及其风险评价   总被引:3,自引:0,他引:3  
山核桃(Carya cathayensis)是我国特有的高档干果和木本油料植物,目前关于山核桃林地土壤重金属污染研究鲜有报道.本研究以典型山核桃产区临安为研究区,系统采集了188个山核桃土壤样品,采用地统计学以及Moran's I等空间分析方法研究土壤重金属的空间异质性,并对山核桃林土壤重金属潜在生态风险进行评价.结果表明,重金属Cd、Cu、Zn、Pb、Ni、Cr平均含量分别为0.37、40.76、87.61、30.10、28.33、56.57 mg·kg-1,其中Cd、Cu平均值分别是背景值的1.33和2.87倍.单因子污染指数、内梅罗污染指数及潜在生态风险评价结果显示研究区土壤重金属均有样点超过土壤背景值,且Cd、Cu、Zn、Pb、Ni有部分样点超过土壤环境质量二级标准,表明研究区土壤已具有Cd、Cu、Zn、Pb、Ni、Cr不同程度的累积特征,局部土壤已受到Cd、Cu、Zn、Pb、Ni的污染,其中Cd最为严重,达到了强生态危害程度,Cu次之,总体上重金属呈中等生态危害程度.基于半方差函数分析得出,Cd、Cu、Pb、Ni、Cr具有强烈的空间自相关,而Zn属于中等空间相关性.Moran's I指数以及克里格插值结果揭示重金属Cd、Cu、Zn、Pb、Ni、Cr均存在明显的空间分布格局和局部空间聚集现象,高值主要集中在太阳、岛石、清凉峰、河桥以及湍口几个乡镇,且以重金属Cd、Cu污染风险概率较高.土壤Cd、Cu、Zn、Ni、Cr高值分布主要与矿区开采有关,而Pb与钾肥的施用密切相关.可见,研究区重金属空间分布特征受人为活动影响明显.  相似文献   

20.
李建辉  张莹莹  黄魁  夏慧 《中国环境科学》2021,40(12):5375-5382
为判定蚯蚓粪作为微生物肥料的潜力,本研究采用宏基因组学的方法,对污泥、牛粪与蔬菜蚯蚓粪样品抽提的DNA进行测序,并将结果进行物种注释及功能注释,以揭示不同蚯蚓粪中功能性微生物的种群结构.结果表明:污泥、牛粪和蔬菜蚯蚓粪分别检测到117505、81182、81104条scaftigs.变形菌门、拟杆菌门、疣微菌门与放线菌门为3种蚯蚓粪的优势菌门.氮磷代谢途径分析表明,蚯蚓粪中富含固氮菌(Rhizobium、Mesorhizobium、BradyrhizobiumAzospirillum)、硝化菌(Nitrosomonas、Nitrosospira、NitrosococcusNitrospira)和溶磷菌(FlavobacteriumPseudomonas、Arthrobacter、Streptomyces)等肥料功能菌.相比而言,蔬菜蚯蚓粪微生物肥料潜力较高.相对于蔬菜蚯蚓粪(371条Unigenes),污泥(2461条Unigenes)和牛粪(965条Unigenes)蚯蚓粪中存在较多的病原菌.而且,污泥、牛粪与蔬菜蚯蚓粪中耐药基因相对丰度高达0.93×10-3、0.32×10-3和0.32×10-3,主要为β-内酰胺类、氨基糖苷类、大环内酯类及四环素类耐药基因等.研究结果显示,蚯蚓粪中有益的功能菌群和有害微生物同时存在,其生物污染物的环境风险值得关注.  相似文献   

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