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1.
赤泥是从铝土矿中提取氧化铝生产过程中产生的残渣。赤泥的产率取决于氧化铝在铝土矿中的品位,据统计每生产1t氧化铝产出的赤泥为0.6~2.5t。由于赤泥的产量大,无论开放或封闭型堆放都将造成环境问题,且占用土地;同时,对于封闭型或赤泥库堆放,赤泥库的建造和维护将提高氧化铝的生产成本。另一方面,赤泥中含有多种有价金属和组分。因此,已有相当多的研究和开发工作在开展,以寻求有效的方法和技术从赤泥中提取有价金属和利用赤泥作为原料生产不同产品。然而,由于赤泥本身含高碱、重金属和放射性元素等,已开发的技术应用非常有限。文章就这些问题进行了评述,另外,就利用赤泥对将来研发方面,提出综合全回收和消耗掉赤泥的初步建议。  相似文献   

2.
赤泥综合利用及其放射性调控技术初探   总被引:5,自引:0,他引:5  
赤泥是氧化铝生产过程中的工业废弃物,目前尚没有对其进行大规模利用的成熟技术.本文通过对赤泥综合利用研究现状及发展趋势的调研和分析,指出最有希望能充分利用赤泥的领域是建筑材料行业,但高放射性是制约其在此领域应用的技术瓶颈.贵州某铝厂赤泥的放射性、物质组成和化学成分分析结果表明,赤泥的放射性主要由原料铝土矿带入,在氧化铝生产过程中逐步富集而成.在此结果上,提出了降低赤泥放射性的一种可行途径:采用重选、磁选、电选、浮选将含放射性元素从赤泥中分离殆尽.  相似文献   

3.
烧结法赤泥的物质组成与颗粒特征研究   总被引:1,自引:0,他引:1  
运用X射线荧光光谱仪、电感耦合等离子体质谱仪、X射线粉晶衍射仪(XRD)、透射电子显微镜和激光粒度分析仪等手段,对贵州烧结法赤泥主量元素和微量元素的化学组成、物质组成、微观形态和粒度分布等基本特征进行系统研究,并将烧结法赤泥的组成与拜耳法赤泥进行对比。结果表明,烧结法赤泥的主要化学成分是CaO、Al2O3、SiO2、Fe2O3、TiO2、Na2O、K2O和MgO,与拜耳法赤泥相比具有高钙低铝的特征。透射电子显微镜分析烧结法赤泥中部分矿物的颗粒形态与特征,XRD分析其主要物相有硅酸二钙、铝酸三钙、方解石、钙钛矿等,还有少量分散的含铁矿物、黏土类铝硅酸矿物。根据微观形态的不同,将烧结法赤泥的组成矿物划分为三类:薄片状或者大块状聚集体;片状、柱状、颗粒状等规则形态;毛发状、细丝状聚集体。通过激光粒度分析仪测量烧结法赤泥的粒径分布情况,表明粒径细小是赤泥的重要特征,同时也是影响赤泥在选矿等领域综合利用的重要因素之一。通过对赤泥物相组成与粒度特征的综合分析,为烧结法赤泥综合利用提供了必要的基础资料和科学依据。  相似文献   

4.
颗粒的迁移对地下水中污染物的迁移起着重要的作用。本文以扎塘赤泥库为例,通过现场采样和室内实验分析相结合的方法,分析了扎塘赤泥库赤泥颗粒的分布特征及赤泥颗粒的迁移规律。分析结果表明:赤泥为一种级配良好的类黏性土回填物;不同取样深度上,赤泥颗粒的分布特征基本趋于一致,不同粒径范围的赤泥颗粒迁移的规律存在着差异,水动力条件对赤泥颗粒迁移的最大粒径起着决定性的作用。  相似文献   

5.
拜耳法赤泥矿物成分特殊,力学性能较差,平果铝赤泥堆场利用拜耳法赤泥筑坝在国内尚属首次。通过对拜耳法赤泥颗分情况、矿物及化学组成、物理力学特性等进行试验研究,认为赤泥中Fe2O3含量较高、粒径较细且属于级配不良的土;结合平果铝赤泥堆场目前的运行情况,分析了赤泥堆场目前运行时存在的排水系统、赤泥固结等几个问题,指出了赤泥堆场堆存后期有可能由于赤泥排水缓慢而导致堆场底部赤泥长期被水浸泡,从而对堆场的稳定性造成一定影响。  相似文献   

6.
拜耳法赤泥具有特殊的物理、水理特性,经过改良处理可用于路基填筑。选择石灰、水泥、磷石膏、复合改性材料对赤泥进行化学改良处理,并分析不同改良材料对赤泥击实特性的影响。试验结果表明:不同材料改良赤泥击实特性差异较大,并随着掺加剂量的变化,每种材料改良赤泥的最佳含水率和最大干密度均呈现不同的增减变化趋势,为拜耳法赤泥改良方法的选择和工程应用提供参考。  相似文献   

7.
贵州铝厂拜耳法赤泥物相组成研究   总被引:2,自引:0,他引:2  
赤泥是铝土矿熔炼氧化铝过程产生的一种尾矿废弃物,根据炼铝工艺不同可以分为拜耳法赤泥、烧结法赤泥及联合法赤泥.近年来随着对低品位铝土矿的利用以及资源综合利用程度的提高,部分拜尔法赤泥被用作烧结法氧化铝生产的配料,但由于拜耳法赤泥排放量大,其堆存量与排放量仍然十分巨大.  相似文献   

8.
以某拟建赤泥堆场为研究区,选取合适的模拟计算参数及边界条件,在平面应变条件下,建立流体模型,利用FLAC~(3D)软件模拟坝体在无防渗、部分防渗、全部防渗设计条件下孔隙水压力分布、滤液渗流路径、渗漏量等,为该尾矿库的防渗设计提供技术依据。模拟结果表明:该软件能较好的模拟赤泥堆场尾矿坝渗漏情况,库区渗漏特性明显,因此为防止环境污染及保证尾矿坝的稳定性,应采用坝体和库区完全防渗措施,并应采用合适的防渗材料。此方法可为尾矿库安全防渗设计提供参考依据和指导施工。  相似文献   

9.
赤泥是制铝工业提炼氧化铝过程产生的固体废弃物。目前,全球累计排放的赤泥约40亿吨,并仍以1亿2000万吨的年排放量不断增加。赤泥现在主要依靠堆场或填海处置,不仅占用大量土地资源、耗费较多维护费用,而且对周边的生态环境造成巨大的污染,因此迫切需要进行赤泥的综合利用。由于赤泥具有颗粒分散性好、比表面积大、吸附性能优、在溶液中稳定性高等优点,近年来在污染控制与环境修复中应用广泛。本文概述了赤泥的种类、矿物组成与理化特性,总结了赤泥在控制地表污水与底泥中磷的应用研究进展,重点探讨了赤泥的不同改性方法、作用机制和除磷效果,并指出了未来可能发展的研究方向。  相似文献   

10.
据保守估算 ,我国每年排放的铝工业固体废料赤泥至少在 5 0 0万 t以上。由于赤泥对生态环境的严重危害 ,赤泥坝、赤泥库的安全已成为令人关注的环境问题。各类固体废弃物 (包括生活垃圾 )储存、处理和利用的研究不仅是当代环境科学的重要任务 ,亦是当代环境工程地质学、环境岩土工程学最重要、最迫切的研究任务之一。本文利用工程岩土学的有关理论和方法 ,系统地研究了赤泥的化学、矿物成分、不良工程特性及其形成变化机理 ,并在此基础上提出了赤泥的储存、加固 (处理 )和综合利用的原理和途径。  相似文献   

11.
Ekrem Kalkan   《Engineering Geology》2006,87(3-4):220-229
Red mud is a waste material generated by the Bayer Process widely used to produce alumina from bauxite throughout the world. Approximately, 35% to 40% per ton of bauxite treated using the Bayer Process ends up as red mud waste. Because of storing issues, the waste negatively affects the environment. To solve this problem, it is essential to investigate different uses for red mud waste. The potential use of red mud for the preparation of stabilization material is presented in this study. This study examines the effects of red mud on the unconfined compressive strength, hydraulic conductivity, and swelling percentage of compacted clay liners as a hydraulic barrier. The test results show that compacted clay samples containing red mud and cement–red mud additives have a high compressive strength and decreased the hydraulic conductivity and swelling percentage as compared to natural clay samples. Consequently, it is concluded that red mud and cement–red mud materials can be successfully used for the stabilization of clay liners in geotechnical applications.  相似文献   

12.
The management of tailings depends on its consolidation behavior to great extent. The red mud tailings in Pingguo, Guangxi is of high water content and void ratio. The present paper takes the red mud aluminiferous tailings in Pingguo, Guangxi as prototype. Model tests were carried out to study the consolidation behavior of red mud aluminiferous tailings that were landfilled layer by layer. The layered settlement and the water discharge caused by self-weight consolidation were studied. The influence of the latter landfilled layer of red mud on the previous layer was analyzed. The results show that the settlement at the surface with time can be divided into two stages. During the first stage, a thin layer of water appeared and the thickness kept increasing at the top of the mud surface with the particle of red mud sinking. During the second stage, water drained from the mud and settlement developed slowly. Cracks developed at the surface due to evaporation and the red mud near the surface became unsaturated. When the previous landfilled layer consolidated to the degree that the water content was less than 40%, the later landfilled layer of red mud will have little influence on the settlement of previous landfilled layer.  相似文献   

13.
水泥系结合料稳定赤泥应用于公路工程是消纳大宗工业固体废料赤泥的新技术路向。目前,路用稳定赤泥耐久性能的研究滞后于工程实践,为对此研究,进行稳定剂配比研究、干湿循环与冻融循环试验和微观试验。结果表明:水泥、石灰和磷石膏结合料稳定赤泥的标准强度最小为3.6 MPa,可满足路面稳定基层承载标准,且5级循环后试样质量损失趋于稳定。磷石膏比例由8%减小到2%,5级干湿循环后强度降低至1.69~3.69 MPa,强度损失率(BDR/%)达到35.1% ~85.4%,5级冻融循环后强度降低至2.63~3.70 MPa,强度损失率(BDR/%)达到54.82% ~79.79%,表明硫激发耦合效应的磷石膏掺量不宜超过赤泥用量的2%。此外,压汞试验研究揭示干湿与冻融循环导致试样大孔隙(直径>0.1 μm)占比增加,并与强度呈显著负相关。综合承载性能与耐久性能试验,使用稳定赤泥替代公路道面水稳材料是可行的,最优配比为赤泥︰水泥︰石灰︰磷石膏=100︰8︰2︰2。基于循环强度衰减特征,工程实践中施工期限制、早期养护质量等至关重要,且应严格控制稳定赤泥中的磷石膏掺量。  相似文献   

14.
对福建沙县钾长石粉合成的13X沸石及其与取自山东铝业公司的赤泥混合使用时除砷的效果和适宜条件进行实验。结果表明,以单一的13X沸石为吸附剂时,改变沸石用量和溶液的酸度均不能有效去除砷;赤泥和沸石混合使用时对低浓度砷(〈5mg/L)具有良好的去除效果。适宜的吸附条件为赤泥用量2g/L,沸石用量1.5g/L,pH值约为8,平衡时间1h。实验表明,赤泥在混合吸附剂除砷过程中起着重要的作用,沸石与赤泥的合理混合使用,对于含砷重金属废水处理具有重要意义。对可能的机理进行了探讨。  相似文献   

15.
渗漏问题一直是赤泥堆场的一个难题。在岩溶地区的赤泥堆场,因岩溶裂隙管道的存在,渗漏的产生是必然的,而防渗处理又是一个比较复杂、系统的工程。而对堆存强碱性(溶液的pH值≥12)液、固体物的堆场,若发生废液外渗,其对环境的危害及影响都较大。对赤泥堆场岩溶渗漏通道采取垂直帷幕注浆、场内封堵落水洞、赤泥铺盖等综合防渗措施进行治理,通过灌浆前后地层的渗透性对比和泉点水质监测,结果表明防渗治理的效果很好。  相似文献   

16.
Red mud residue from alumina production has been proposed as an alternative liner material. The chemical and environmental compatibility of red mud upon exposure to representative organic (methanol, heptane, TCE, and acetic acid) and inorganic liquids (CaCl2 and seawater) was studied. Chemical compatibility assays comprised Atterberg limits and sedimentation and hydraulic conductivity tests for red mud interacted with the chemical liquids, whereas the environmental compatibility was assessed through the leaching of metals from red mud as permeated with the liquids. Methanol greatly reduced the plasticity at concentrations ≥80 % by volume, but it did not increase the hydraulic conductivity of compacted red mud. High concentrations (≥60 % v/v) of acetic acid reduced the plasticity and enhanced the sedimentation of red mud. Conversely, acetic acid concentrations ≤40 % caused dispersion, but damaged the hydraulic properties and structure of red mud. The percolation of a pH 2 acetic acid solution did not adversely affect the hydraulic performance of the red mud liner. Neither diluted heptane nor TCE affected the red mud. However, pure organics suppressed the plasticity and induced aggregation of red mud, suggesting a great detrimental effect on red mud liners. The red mud exhibited great resistance to attack by inorganic salt solutions. Some concerning leaching of metals (primarily Al and Cr) occurred as water, acetic acid, and CaCl2 solutions percolated through red mud, but effluent metals concentration quickly dropped to permissible levels. In general, red mud exhibited a high resistance against chemical attack; nevertheless, exposure to low-dielectric-constant organic chemicals should be avoided.  相似文献   

17.
王伟  周岩 《吉林地质》2012,31(2):143-146
简要介绍我国目前钻井废弃泥浆无害化处理的现状,废弃泥浆对环境的影响,目前常用钻井废弃泥浆无害化固化处理技术。通过实例对勘探矿区内的钻孔产生的废弃泥浆进行无毒和无害化评价,并进行一次无害化和固化处理技术及工艺的大胆尝试,取得点滴体会供同行们分享,推动岩心钻探环境保护工作。  相似文献   

18.
In this study, feasibility of using seawater to neutralize alkaline red mud for its safe disposal has been studied using Taguchi’s design of experimental methodology. Parameters such as weight of red mud, volume of seawater, stirring time and temperature were tested at three levels to study their effect on response characteristic, i.e., pH of the neutralized slurry. The analysis of variance showed that volume of seawater added and quantity of red mud are the two significant parameters with 53.59 and 44.92 % contribution each, respectively. Under the optimized parameters, pH value of red mud slurry reaches to about 8.0 which is within disposable limits. When seawater or other Ca- and Mg-rich brines are added to caustic red mud, the pH of the mixture is reduced causing hydroxide, carbonate or hydroxy carbonate minerals to be precipitated. This mechanism of neutralization process has been explained with emphasis on chemical analysis, mineralogy and morphology of the neutralized red mud. The process improved the physical characteristics of red mud with entrained liquor becoming non-hazardous water with reduced alkalinity. The results would be extremely useful in the process of safe disposal of red mud.  相似文献   

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