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以红土镍矿酸浸产生的废水为原料,采用氧化-中和水解法沉淀铁,氢氧化钙沉淀法沉镁制备无机填料,为红土镍矿酸浸废水中有价金属的回收利用提供依据。研究了沉铁过程中温度和反应终点pH值对沉铁率及镁损失率的影响,获得适宜的沉铁条件为:温度40 ℃、pH=4.0,此时沉铁率可达99.86%,镁损失率约为2%。同时研究了沉镁过程中反应时间、反应温度、搅拌速度、镁钙摩尔比对镁沉淀率和钙利用率的影响,结果表明:温度50 ℃、搅拌速度300 r/min、反应时间2 h、镁钙摩尔比1∶1.2时,沉镁率可达99.53%,钙利用率为96.46%。采用XRD和SEM分析了沉镁产物的组成和结构,表明其为[Mg(OH)2-CaSO4·2H2O]混合物,可用作无机填料。 相似文献
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红土镍矿加压酸浸工艺进展 总被引:4,自引:0,他引:4
随着硫化镍矿资源的逐渐减少,高效且低成本的开发红土镍矿资源以满足逐渐增加的镍需求有着重要意义。据此,本文首先介绍了红土镍矿的矿物学特性及其加压酸浸工艺的反应机理,并从提高镍浸出率、降低酸耗角度概述了该工艺的影响因素;其次从工业应用角度介绍了该工艺的技术改进,着重介绍了加压酸浸—常压酸浸工艺(HPAL-AL)和非常规介质浸出工艺。 相似文献
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世界红土型镍矿开发和高压酸浸技术应用 总被引:27,自引:0,他引:27
由于世界镍需求增长和硫化镍资源短缺,红土型镍矿资源开发将成为未来十年镍业发展的主要趋势。1999年以来,澳大利亚西部新建的总投资20多他澳元的三个高压酸浸技术HPAL镍厂成为该趋势的标志。文章分析了红土型镍矿资源开发利用的长处及其两种类型,重点介绍了高压酸浸HPAL技术在西澳镍厂应用近况、问题、原因及纠正措施,并论述了该技术在未来世界镍业发展中的应用趋势。 相似文献
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针对我国云南某含镍、铁有价金属低的硅镁型红土矿,利用X射线衍射、扫描电子显微镜、光学电子显微镜等检测手段,开展了矿物工艺学研究.结果表明,红土镍矿主要包括蛇纹石和石英、褐铁矿、赤铁矿、磁铁矿、铬铁尖晶石等其它矿物.铁主要以褐铁矿、赤铁矿和磁铁矿的形式存在,充填分布在脉石矿物的边缘和间隙中;蛇纹石分布比较广泛,集合体呈块地存在红土镍矿中;石英呈重结晶菊花状,由细小晶粒集合成大结晶体;镍分散嵌布在铁矿物和蛇纹石等脉石中,镍在铁矿物中有相对的富集,而在蛇纹石等脉石中分布密度较少,未观察到独立的镍矿物存在. 相似文献
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Processability of complex, low-grade nickel (Ni) laterite ores via heap leaching is very limited due to some intractable geotechnical and hydrological challenges such as poor heap porosity/permeability and structural stability. This work presents some investigations on laboratory batch drum agglomeration and continuous column leaching behaviour of saprolitic (SAP) and goethitic (G) Ni laterite ores as part of the quest for an effective ore pre-treatment process for enhanced heap leaching. As a focus, the effect of ore mineralogy/chemistry on the agglomeration and column leaching behaviour of −2 mm (crushed from −15 mm run-of-mine) G and SAP Ni laterite ores was examined. To produce ∼5–40 mm agglomerates in <15 min, the SAP ore required a higher H2SO4 (30 wt.%) binder dosage compared with the G ore, although both ores displayed substantially similar, coalescence-controlled agglomeration mechanism. The resulting G agglomerates were more robust than the SAP ones based upon their compressive strength and acidic solution soak test measurements. However, over 100 days of continuous column leaching, the structural stability of the SAP agglomerate bed was slightly greater than that of G agglomerates, reflecting a lesser slump of the former. The pregnant leach solution analysis revealed greater Ni/Co extraction rates from the SAP than the G agglomerates. Whilst the total mass of acid consumed per ton dry ore processed was greater for the SAP ore, the total kg acid per kg Ni extracted was markedly lower. Incongruent leaching of gangue minerals’ constituent elements (e.g., Fe, Mn, Mg, Al and Si) occurred and contributed significantly to the overall acid consumption. The findings show the relevance of agglomeration and column leaching tests for providing useful information for plant designing and optimization of Ni laterite heap leaching operations. 相似文献
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Activation pretreatment of limonitic laterite ores by alkali-roasting method using sodium carbonate 总被引:3,自引:0,他引:3
Activation pretreatment of Cr-containing limonitic laterite ores by Na2CO3 roasting to remove Cr and Al, as well as its effect on Ni and Co extraction in the subsequent pressure acid leaching process were investigated. X-ray diffraction (XRD), thermogravimetric (TG), and scanning electron microscopy/X-ray energy dispersive spectroscopy (SEM/XEDS) techniques were used to characterize the laterite ores and the water leaching residues of alkali roasting and found that goethite is the major Ni-bearing mineral and chromite the minor one. Alkali-roasting pretreatment breaks the mineral lattices of the laterite, exposing their Ni and Co, which leads to higher extraction of these two metals under milder operation conditions in the subsequent pressure acid leaching process. Experimental results showed that the leaching of Cr and Al were up to 99 wt% and 80 wt%, respectively, under optimal alkali roasting and water leaching conditions. Compared with the direct pressure acid leaching of the raw laterite ores, leaching of Ni and Co increased from 79.96 wt% to 97.52 wt% and 70.02 wt% to 95.33 wt%, respectively, after alkali-roasting activation pretreatment was performed. Meanwhile, the grade of acid leaching iron residues increased from 55.31 wt% to 62.92 wt%, and these residues with low Cr content could be more suitable as the raw materials for iron-making. 相似文献
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Atmospheric leaching of nickel from limonitic laterite ores is regarded as a promising approach for nickel production, despite its low nickel recovery and slower leaching rate than high pressure acid leaching. Sulfur dioxide can enhance the sulfuric acid leaching of laterite, but its behavior for enhancing atmospheric sulfuric acid leaching was uncertain due to SO2 losses and emission. In this study, sodium sulfite was used as a substitute for SO2 gas in the leaching and the sulfuric acid leaching characteristics of Ni and Fe from a limonitic laterite in the presence of sodium sulfite were investigated. A linear correlation exists between the extraction of Ni and Fe, indicating the difficulty in selective leaching of Ni over Fe. Most nickel is isomorphically substituted within the goethite and it is difficult to dissolve in a high oxidation–reduction potential solution environment, resulting in a low nickel recovery. SO2(aq) generated from the reaction of sodium sulfite in sulfuric acid solution, lowers the potential for the reducing reaction of FeOOH to give Fe2+, accelerating the iron extraction and nickel liberation from goethite. 相似文献
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硫酸烧渣中铁的综合利用研究进展 总被引:1,自引:0,他引:1
综述了硫酸烧渣中铁的综合利用途径及最新研究进展。重点对硫酸烧渣中铁的各种提取方法的适用条件、存在问题进行了分析和对比,指出直接活化酸溶法具有工艺简单、节能环保等优点,工业化应用前景良好。 相似文献
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An innovative technology for processing saprolitic laterite ores from the Philippines by hydrochloric acid atmospheric leaching and spray hydrolysis is proposed. The factors that affect the hydrochloric acid atmospheric leaching of the laterite ores and spray hydrolysis of the atmospheric acid leach solution are investigated. Experimental results show that the leaching of Ni, Fe, and Mg is 98.9 wt%, 97.8 wt%, and 80.9 wt%, respectively, under optimal acid leaching conditions. The hydrolysis of Ni and Fe by the atmospheric acid leach solution approaches 100 wt% at the temperature range of 450–500 °C. Characterization results show that a serpentine mineral, nominally Mg3Si2O5(OH)4, is the major component and goethite, FeO(OH), is the minor one in the laterite ores. Treatment by hydrochloric acid atmospheric leaching breaks the mineral lattices of the laterite ores and makes amorphous silica the primary product in the atmospheric acid leach residue. The grade of Ni in the hydrolyzate increases to 4.55%. The hydrolyzate with high Ni content can be utilized for ferro-nickel production. 相似文献
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对铅冶炼难处理复杂氧化锌烟尘碱洗渣进行了\"中性浸出—酸浸\"工艺试验研究。结果表明,碱洗渣中性浸出时,锌、镉的浸出率先随浸出温度、液固比、搅拌速度和时间的增加而提高,后增速变缓;中浸渣酸浸时,液固比对锌、铟的浸出率无明显影响。锌、铟的浸出率随初始酸度、浸出温度和时间的增加先增加后变缓。中性浸出最佳条件为:温度338K、液固比5∶1、搅拌速度400r/min、浸出时间1h,此条件下,锌、镉的浸出率分别为80.3%和76.3%。中浸渣酸浸最佳条件为:初始酸度100g/L、浸出时间2h、浸出温度363K、液固比5∶1,在该条件下,锌、铟的浸出率分别为97.1%和85.5%。 相似文献