Pressure acid leaching of arid-region nickel laterite ore: Part I: effect of water quality

The effect of water salinity on the reactions occurring during pressure acid leaching of an arid-region laterite ore, using hypersaline water, seawater, sub-potable water and tap water, is examined. Particular emphasis is placed on the mineralogy of the residue and its implications with regard to residue volume/mass, overall acid consumption and nickel extraction. Analysis of a pressure acid leach residue by electron microprobe indicates that the residual nickel is present in phases that contain silicon and varying concentrations of aluminium, but are deficient in sulphur. Incomplete extraction of nickel from the ore may not be attributed to any one mineral phase.     

铜尾矿选矿综合回收试验研究

对某铜尾矿选矿综合回收进行了试验研究,采用全浮选工艺使有用组份得到高效回收,获得指标为:超纯硫精矿S品位51.12%,含Cu0.13%、Fe 45.7%,S回收率49.18%;明矾石精矿SO3品位23.99%(纯明矾石含量62.15%),SO3回收率72.65%;地开石粗精矿Al2O3品位22.08%(纯地开石含量80.53%),Al2O3回收率65.25%;最终尾矿SiO2含量91.99%,可作为冶炼熔剂、铸造石英砂或建材使用。     

明矾石综合利用技术研究进展

明矾石是未大规模开发利用的富含K、Al、S的矿物。为了推动明矾石综合利用技术的进步,促进明矾石的大规模开发,在概述了明矾石的基本性质,国内分布情况及资源化综合利用研究现状的基础上,分析了各技术路线中影响明矾石大规模产业化开发利用所存在的问题,对比了高温焙烧工艺和热压浸出工艺的技术特点和工业化难度,指出明矾石的高温焙烧工艺虽都能实现钾、铝元素的提取,但是工序复杂,成本高,焙烧能耗大,该技术方向降本潜力小,因而工业化难度大;而直接热压浸出明矾石工艺没有明矾石的焙烧工序,且浸出过程中的热量易于回收利用,因而该工艺具有能耗和成本低,投资小,工艺简单,流程短等优势。其中的碱法工艺与高温焙烧工艺相比,省去了球磨磨矿、高温焙烧脱水、还原和硫酸制取等工序,流程大为缩短,能耗明显降低,且无废气、废灰,减少了环境污染,但该法存在浸出过程中烧碱消耗量过大,碱原料成本高,对含硅高的明矾石还存在氢氧化铝提取成本太高的问题。而直接加压酸浸工艺对明矾石的品位要求不高,产品硫酸钾、氢氧化铝、石膏等具有极大的市场容量,因而适合大规模产业化开发。     

Phosphate adsorption characteristics of alunite to be used as a cement additive

The adsorption of phosphate from aqueous solution by alunite has been investigated as a function of calcination temperature, particle size, pH, agitation time and initial phosphate concentration. Phosphate adsorption was seen to increase with increasing calcination temperature, decreasing adsorbent particle size and pH. The adsorption isotherm data were fitted to the Langmuir isotherm. The alunite exhibited the highest phosphate uptake capacity at 1073 K calcination temperature, at a particle size of 90-150 μm, at the initial pH of 5.0, at an equilibrium time of 60 min and at the initial phosphate concentration of 20×10⁻⁴ mol/l. The adsorption capacity, Q, was 4.697×10⁻³ mol/g at initial pH 5.0.     

利用明矾石掉硫酸钾和聚羟基铝铁

针对明矾石酸法制氧化工艺中除铁难且制得的氧化铝成本高的问题，提出了一种新的明矾石综合利用工艺－－利用明矾石制取硫酸钾和聚羟基铁以及烟草氮钾复肥。工艺充分利用明矾石中钾、铝、硫等有用成分、把铁也作为有用成分，变废为宝。工艺中不主了硫酸分解氯化钾制盐酸工序，解决了聚羟基铝铁原料盐酸的来源和氨解母硫酸钾太稀的问题。     

Optimal field sampling for targeting minerals using hyperspectral data

This paper presents a statistical method for deriving optimal spatial sampling schemes. It focuses on ground verification of minerals derived from hyperspectral data. Spectral angle mapper (SAM) and spectral feature fitting (SFF) classification techniques were applied to obtain rule mineral images. Each pixel in these rule images represents the similarity between the corresponding pixel in the hyperspectral image to a reference spectrum. The rule images provide weights that are utilized in objective functions of the sampling schemes which are optimized through a process of simulated annealing. A HyMAP 126-channel airborne hyperspectral data acquired in 2003 over the Rodalquilar area in Spain serves as an application to target those pixels with the highest likelihood of occurrence of a specific mineral and as a collection the location of these sampling points selected represent the distribution of that particular mineral. In this area, alunite being a predominant mineral in the alteration zones was chosen as the target mineral. Three weight functions are defined to intensively sample areas where a high probability and abundance of alunite occurs. Weight function I uses binary weights derived from the SAM classification image, leading to an even distribution of sampling points over the region of interest. Weight function II uses scaled weights derived from the SAM rule image. Sample points are arranged more intensely in areas of abundance of alunite. Weight function III combines information from several different rule image classifications. Sampling points are distributed more intensely in regions of high probable alunite as classified by both SAM and SFF, thus representing the purest of pixels. This method leads to an efficient distribution of sample points, on the basis of a user-defined objective.     

明矾石无收缩自流灌浆料在设备基础二次浇灌层上的应用

本文通过对明矾石无收缩自流灌浆料在设备基础二次浇灌层上的使用情况 ,对明矾石无收缩自流灌浆料的材料配比、施工方法进行了说明。本文认为在普通灌浆料难以施工、难以保证工程质量的一次浇灌层上 ,明矾石无收缩自流灌浆具有广泛的使用价值     

Alunite processing method selection using the AHP and TOPSIS approaches under fuzzy environment

Alunite is the most important non bauxite resource for alumina. Various methods have been proposed and patented for processing alunite, but none has been performed at industrial scale and no technical,operational and economic data is available to evaluate methods. In addition, selecting the right approach for alunite beneficiation, requires introducing a wide range of criteria and careful analysis of alternatives.In this research, after studying the existing processes, 13 methods were considered and evaluated by 14 technical, economic and environmental analyzing criteria. Due to multiplicity of processing methods and attributes, in this paper, Multi Attribute Decision Making methods were employed to examine the appropriateness of choices. The Delphi Analytical Hierarchy Process(DAHP) was used for weighting selection criteria and Fuzzy TOPSIS approach was used to determine the most profitable candidates. Among 13 studied methods, Spanish, Svoronos and Hazan methods were respectively recognized to be the best choices.     

铜尾矿浮选明矾石精矿中有价元素直接碱浸动力学及过程强化

作为一种多元素矿物,紫金山铜尾矿浮选明矾石精矿有望成为铝、钾和镓等元素的替代资源。相对于传统工艺,KOH溶液直接浸出明矾石精矿可以避免高能耗的热分解过程,同时降低杂质离子的干扰。本工作研究了铜尾矿浮选明矾石精矿在KOH溶液中的直接浸出行为特性,重点研究了不同碱浓度和温度下精矿中多元素浸出率随时间的变化规律,并结合动力学分析阐明了精矿直接碱浸反应的控制步骤;在此基础上,引入机械活化促进精矿中有价元素的高效浸出。结果表明,在实验条件下精矿直接碱浸过程中仅发生明矾石相的分解;提高KOH浓度和浸出温度可使元素浸出速率快速增加;根据经典的液-固反应收缩核模型的动力学理论,分析发现浸出反应符合化学反应步骤控制。机械活化使精矿粒径降低、比表面积增加、非晶化程度提高,从而使精矿的反应活性增强,使铝、钾和镓的浸出速率提高。     

明矾石精矿焙烧—酸浸提取K和Al

福建紫金山选铜尾矿浮选得到的明矾石精矿主要化学组成为Al2O3、Si O2、K2O和SO3,主要矿物组成是明矾石、石英、地开石。为从该明矾石精矿中提取有价元素Al、K,进行了焙烧—浸出试验。结果表明:明矾石精矿在600℃焙烧1 h,焙烧产品在硫酸浓度为60 g/L、浸出温度为80℃、液固比为6、浸出时间为0.5 h条件下搅拌浸出,K的浸出率为98.47%,Al的浸出率为94.35%;浸出后浸渣的主要化学成分是二氧化硅和氧化铝,二者含量合计达到90.44%,可作为建筑原料。试验结果可以为酸法综合利用明矾石精矿提供技术指导。