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1.
改性铝土矿做净水剂，与市售其它混凝剂比较，具有ＰＨ值适用范围宽，对水中阴阳离子，尤其是对ＳＯ＾２－４的吸附能力强等优点。去除水中的浊度，颜色，ＣＯＤ等同于市售其它混凝剂。 相似文献
2.
靖西堆积型铝土矿,就是指其境内赋存于上二叠统合山组底部古风化壳型铝土矿（亦称原生铝土矿）,在新生代的表生条件下,遭受长期性的岩溶作用和红土化作用,使原生铝土矿剥蚀、崩落、迁移,同碳酸盐岩的溶蚀残留物堆积于岩溶洼地、谷地中或缓坡上的一套含铝土矿的堆积组合物。堆积型铝土矿主要分布在以石炭系、二叠系下统地层为基底的岩溶洼地及缓坡地上。堆积铝土矿体的形成、规模、含矿率、矿石质量受原生沉积铝土矿体、岩溶洼地大小、矿源层所处位置、地形地貌及地层等因素控制。峰丛洼地是堆积铝土矿最主要的分布区段;原生铝土矿体规模越大,则形成的堆积铝土矿体规模越大;含矿洼地封闭性较好,则矿体厚度大,含矿率较高。 相似文献
3.
《International Journal of Mineral Processing》2005,77(1):46-52
Experiments have been conducted in a shear cell in order to provide insight into the separation of flocs by size and density in a hydrocyclone. The size of the aggregates was measured after shearing at a rate comparable to that found within a typical hydrocyclone. Two types of coal tailings from the Hunter Valley, NSW Australia with average sizes of about 0.4 μm and 10 μm were investigated. The size of aggregates after shearing was measured for a range of different polymeric flocculants of varying molecular weight and charge density. Under certain conditions 90% of the aggregates from the submicron tailings have size greater than 38 μm after shear at 1200 s− 1 for 30 s. The aggregates produced from the 10 μm tailings had over 90% larger than 82 μm with the flocculants tested. The size of the aggregates remained sufficiently large after shearing to be suitable for hydrocyclone dewatering. The density of the aggregates was calculated from the aggregate size and mass fractal dimension. The small difference between the density of the aggregates and water was found to be the factor limiting their velocity under the applied centrifugal acceleration. 相似文献
4.
Study on the flocculability of metal ions by<Emphasis Type="Italic">Bacillus mucilaginosus</Emphasis> GY03 strain 总被引：1，自引：0，他引：1
This study deals with the flocculability of two types of metal ions by Bacillus macilaginosus GY03 Strain, with an emphasis on the influence of pH conditions, volume and time of flocculants produced by GY03 Strain on the adsorption of metal irons such as Pb^2 and Mn^2 and the capabilities of floceulants to adsorb metal ions of different concentrations. The results showed that microbial flocculants produced by Bacillus mucilaginosus GY03 Strain are highly capable of flocculating metal ions, but show different effectiveness with respect to the adsorption of Pb^2 and Mn^2 . In accordance with the experimental data and actual waste-water treatment conditions, the relevant regression equation of floeculation has been deduced, which has found some application in practice. The experimental results of this study demonstrated that microbial flocculants produced by Bacillus mucilaginosus can be used to treat metallic ion-containing waste water. In practical application the volume of microbial floceulants required and flocculation conditions should be taken into comprehensive consideration in accordance with the properties of metal ions, the composition of anions and the solubility of other metals, in combination with the cost and effectiveness of floceulants to be used. Floeeulant used in this experiment has the advantages of being applied over a wide range of pH values, small flocculant volume, and rapid speed of floeeulation. So this kind of flocculant is within excellent prospect of application. 相似文献
5.
Inrecentyears,withtherapiddevelopmentofindustrialeconomy ,wastewaterisdischargedinhugevolumeandtheaccumulationofheavymetalionsinsoilsandwatersourcesisspeededuprapidly .Asaresult,waterpollutionhasbecomeadailydeterioratingproblem .Heavymetalsareeasytoenterthefoodchain ,therebyconstitutingagreatthreattothehealthofanimalsandhu manbeings .Therefore,howtoeffectivelyhandleheavymetalpollutionhasbecomeacommonat tractionformankind .Theroutineheavymetaltreatmentmethodsaremainlythechemical,phys icalandphy… 相似文献
6.
《International Journal of Mineral Processing》2005,76(3):173-180
The process of pelleting flocculation, a further development of classical flocculation technology, is defined as a formation of wet pellets directly in a liquid medium. Apart from well described mechanisms of flocculation like perikinetic and orthokinetic flocculation, the mechanism responsible for the formation of dense agglomerates is the mechanical syneresis guaranteed by the appropriate reactor form. Upon the two established models in the literature: the series system and the parallel system, experiments were performed to simulate a layer-by-layer particle deposition on the so-called “mother seeds” conforming to the parallel system.The present paper deals with the results originating from laboratory scale experiments with model sludge, kaolin suspension. The layering process was conducted in the presence of different cationic flocculants and the resulting relationships with respect to their nature and to the applied energy level have been assessed. The achieved agglomerates exhibit an “onion like” structure with densities up to 1.42 g/cm3 and solid matter content up to 48% after gravity dewatering. Thus generated sludge agglomerates reveal the optimisation potential for sludge treatment manifested by improved characteristics achieved during the conditioning. 相似文献
7.
铝类絮凝剂对细颗粒泥沙絮凝沉降有重要作用,常应用于浑水澄清、农业污水处理等研究中。在AlCl3浓度为0～1.7mmol/L,泥沙浓度为10g/L时,用吸管法研究了AlCl3对细颗粒泥沙絮凝沉降的影响,结果表明:在液面下同一深度,泥沙浓度随时间呈指数衰减;悬液经多次搅拌后再沉降,其沉速减缓;当AlCl3浓度为0.9～1.7mmol/L时,出现明显的清浑水交界面,交界面随时间等速下降,平均沉速为4.756cm/min,对应的絮团平均粒径为0.0315mm;土娄土絮凝临界粒径为0.027mm。 相似文献
8.
Y.A. Attia 《International Journal of Mineral Processing》1977,4(3):209-225
Problems encountered in developing a selective flocculation process for a complex copper ore and ways of overcoming these difficulties are reported. To obtain a useful enrichment ratio, multiple stages of flocculation and redispersion were found necessary in order to release entrapped, unwanted particles. Particular attention was given to the dispersion process of the ore suspensions, and the importance of mechanical and chemical factors were established. The effects of solids content and quality of water on the performance of selective flocculation have been investigated. The possibility of developing new, selective or more powerful dispersants was confirmed and one such reagent was tested. 相似文献
9.
为实现疏浚淤泥高效快速脱水减容，选取化学絮凝和真空预压相结合的脱水技术，利用自制真空预压抽滤装置对5种类型絮凝剂调理淤泥进行系列室内脱水试验，通过上清液高度、泥水分界面高度、沉降速率、底泥含水率等指标，综合评价疏浚淤泥沉降过程与深度脱水效果。结果表明：5种絮凝剂对应最优添加量分别为Ca(OH)2(1 500 mg/L)、PAFSI(200 mg/L)、PAC(200 mg/L)、HCA(50 mg/L)、APAM(500 mg/L)；与原始淤泥自然沉降过程相比（底泥高度17.14 cm、含水率96.8%），真空预压可实现絮凝调理淤泥脱水减容、底泥平均含水率降至53.5%，使底泥体积进一步压缩20.48%～36.99%；真空预压作用下，絮凝调理淤泥在50 min内达到沉降速率峰值，前120 min内淤泥絮凝效果明显、泥水分离程度占据主导；与原始淤泥真空预压对比，絮凝?真空预压大幅提升淤泥沉降速率、有效缩短峰值对应沉降时间，最优絮凝剂（APAM）底泥沉降速率峰值、淤泥总高度沉降速率峰值对应时间点缩短87.5%和83.33%，峰值速率分别增加3.56倍、5.18倍；添加适量絮凝剂能有效改善淤泥脱水性能，增大泥粒尺寸、防堵促排，加速疏浚淤泥沉降与泥水分离效率。化学絮凝?真空抽滤技术有利于实现疏浚淤泥减量化，显著缩短工期、加快施工进度、减少堆积占地，具有显著的工程应用价值。 相似文献
10.
The possibility was investigated of carrying out selective flocculation in the model set smithsonite-dolomite using polymers containing nitrogen atoms, which should interact selectively with zinc minerals.A high activity of flocculants in relation to smithsonite and a low activity towards dolomite was observed. However, the activation of the dolomite surface by Zn2+ ions was determined whereby the selective flocculation was not observed in the mixture of smithsonite and dolomite. 相似文献
11.
Solid–liquid separation of tailings slurries in gravity thickeners relies on the efficient mixing of slurry and dilute polymer flocculant solutions within the feedwell. Computational fluid dynamics (CFD) can provide predictions of solids distribution, liquor velocity and shear rate within a feedwell, and with the incorporation of an adsorption model, can also assess the effectiveness of flocculant mixing. This study presents the first use of feedwell CFD to examine the effect of the flocculant inlet direction and velocity on the subsequent distribution and adsorption of flocculant. When flocculant is injected inside the feed stream, a high inlet nozzle velocity will maximise adsorption, with injection preferably vertically upward or towards the feedwell walls. For injection inside the dilution stream (vertical upflow of liquor within the feedwell), the flocculant should be directed either upwards or inwards away from the strong downward flow of the feed stream, with the velocity not critical.At flocculant inlet velocities predicted by CFD to enhance mixing and adsorption, the shear rate experienced within the injection pipe exceeds that in the feedwell, and the duration under higher shear may be greater. Pipe flow studies for several flocculants have confirmed reductions in activity at a solution concentration of 0.025 wt.%; this effect diminishes with greater dilution. Much of this lost activity is recovered on standing, indicating that the applied shear leads to a mixture of chain scission (irreversible) and entanglement (reversible). Minimising the duration of such shear effects on flocculant solution transport to the feedwell is essential, as the potential for increased flocculant demand and reduced flocculation efficiency can easily exceed any benefit from improved feedwell mixing. 相似文献
12.
D.F. Bagster 《International Journal of Mineral Processing》1985,14(1):21-32
Having previously established a system of hematite and silica which can be separated effectively using long-chain polyacrylamide flocculants (Part 1) a stirred tank system was chosen to enable physical variables of flocculant concentration, impeller speed, time of flocculation, slurry concentration, ratio of hematite to quartz in the feed and particle size distribution to be studied.It was concluded that the time of flocculation allowed should be kept short and that there is an optimum of impeller speed though not a sharp one. Slurry concentration must be kept to 1% w/w to prevent serious performance deterioration. A clear optimum flocculant concentration was not found under present circumstances though very low concentrations (< 1 ppm) gave poor results while high concentrations gave no improvement on the results at about 2 ppm.Comparison between an impeller and a propeller of the same diameter and location in the tank pointed to the possibility of critical agitation configurations and the need for caution in scaling up results.The grade of material settling from a selective aggregation process is heavily dependent on the particle size distributions of the mineral species. Larger flocculated minerals produce richer flocs. 相似文献
13.
A. Biati A. R. Karbassi Ph.D. A. H. Hassani Ph.D. S. M. Monavari Ph.D. F. Moattar 《International Journal of Environmental Science and Technology》2010,7(2):327-336
Flocculation can be considered as an effective mechanism in self-purification of metals during estuarine mixing. In the present investigation, flocculation of metals during mixing of Minab River water with the Strait of Hormuz (The Persian Gulf) water is studied for the first time. Flocculation behavior of metals (except for Pb) is governed by dissolved organic carbon. The source of dissolved organic carbon is terrigenous in the estuarine waters of study area. The general pattern of flocculation of studied metals is manganese (180 μg/L) > zinc (88 μg/L)> nickle (73 μg/L)> copper (30 μg/L)> lead (19 μg/L). The results of present study show that metal species are a very important factor in overall flocculation rate. It is found that solids and oxides have the highest and lowest flocculation levels, respectively. Eh-pH diagram indicated that lead is present as lead oxide in Minab River water and the least flocculation rate is attributed to this element. The results also showed that flocculation rate of metal species could be as solids > free ions ≈ hydroxides > oxides. The amount of metal flocculation is about 30.5, 6.6, 25.3, 10.4 and 62.5 ton/y for zinc, Pb, Ni, Cu and Mn, respectively. 相似文献
14.
我国铝土矿资源合理开发利用的探讨 总被引：14，自引：3，他引：14
分析我国铝土矿开发利用的现状以及存在的问题 ,指出我国铝土矿的特点是多为一水硬铝石型矿石 (占 98.4 6 % ) ,且是高铝高硅低铁 ,用其生产氧化铝成本高 ,矿石开采难度大。探讨今后合理开发利用铝土矿的途径 相似文献
15.
福泉矮蹬地区铝土矿、赤铁矿均产于石炭系九架炉组（Cjj）地层中下部,产出层位较稳定,延伸规模大.矿体呈层状、似层状、透镜状产出,产状与地层产状基本一致,矿石品位较高,变化较小.含矿岩系底厚度严格受下伏地层泥盆系上统高坡场组（D3g）厚层白云岩风化壳（喀斯特地貌）起伏控制.将该区铝土矿与修文地区大豆厂九架炉组（Cjj）铝土矿床含矿岩系等进行对比,揭示了本区铝土矿的独特之处.结合九架炉组分布范围、厚度及其变化等,对该区铝土矿资源找矿潜力进行了初步评价,拟为下一步在该区实现铝土矿的找矿突破提供一定的参考. 相似文献
16.
豫西礼庄寨隐伏铝土矿床是应用可控源测量发现的,矿区发育有与华北型铝土矿关系密切的石炭系本溪组,通过可控源音频大地电磁测量,发现了一系列起伏不平的卡尼亚低阻(体)带,钻探验证表明其正好反映了奥陶系顶板古侵蚀面分布特点,从而为隐伏铝土矿床靶区预测指明了方向.本文系统总结了礼庄寨矿床的地质地球物理特征以及隐伏铝土矿床的地球物... 相似文献
17.
This paper presents the results of investigation on uptake of radioactive species 90Sr and 137Cs present in the liquid effluents from nuclear processing plants. Chemical precipitation process is adopted to remove radioactivity from the effluents with low and intermediate level of activity. In this process, radioactive 90Sr and 137Cs are co-precipitated along with copper ferrocyanide, ferric hydroxide and either calcium phosphate or barium sulphate. These precipitates being fine in size require flocculation for enhanced settling rate in clarifier/thickener. The flocculation by some selected high molecular weight polyacrylamide based polymers has improved the uptake of radioactive metal ions. The adsorption of these radioactive species has been found to increase in the presence of these flocculants thereby improving the decontamination factor (DF). While flocculating the precipitates, there may be some complex formation with Sr2+/Cs+, flocculant and the substrate. This has enhanced the uptake of the radioactive metal ions from the liquid component. The plant trials have indicated the improvement of DF value due to flocculation by cationic flocculant. 相似文献
18.
利用X射线荧光光谱法测定铝土矿中主成分A l2O3、SiO2、Fe2O3、TiO2。采用四硼酸锂-偏硼酸锂作熔剂,溴化锂作脱模剂,国产高频熔样炉高温熔融制备玻璃圆片,以标准物质制作校准曲线进行测定,并与化学法进行对照,结果基本一致。方法操作简单、快速,准确度和精密度均达到国家标准方法规定的要求,已用于实际生产中。 相似文献
19.
贵州大竹园大型铝土矿是中国近年来取得重要找矿进展的大型铝土矿之一。以采自大竹园矿区栗园向斜不同部位铝土矿、铝土岩和黏土岩的样品为研究对象,分析了这些样品的稀土元素含量（质量分数）特征及空间分布特征,研究了稀土元素含量与铝土矿质量及成矿过程的关系,最后就稀土元素对于成因和环境的指示意义进行了讨论。结果表明：铝土矿、铝土岩和黏土岩稀土元素总含量（不包括Y）分别为107.07×10-6、185.00×10-6和246.28×10-6,依次增高,说明铝土矿的成矿过程是一个稀土元素贫化的过程,也是Eu异常和Ce异常趋于增大的过程,即相对于黏土岩来说,铝土矿具有高Eu异常、Ce异常的特征;相对于重稀土元素来说,无论是栗园向斜西翼还是东翼,铝土矿轻稀土元素相对富集,且轻稀土元素含量以及La与Yb含量之比均随深度变浅而增加;单纯利用稀土元素图解不能有效反映成矿物质的来源,但可以大体反映含矿岩系形成于海相或海陆过渡相环境;大竹园大型铝土矿与黔北其他铝土矿一样,总体上属于沉积型,可能与古喀斯特化过程、古风化过程有关。 相似文献