中国磷块岩矿石选矿评价预测技术的系统研究

在确立磷块岩矿石中化学组分与矿物组分间的数量关系,并对大量选矿试验结果的主要化学组分分配率进行统计分析的基础上,制定了预测精矿产率和主要化学组分的计算公式。根据不同磷肥产品对磷矿石的质量要求,制定了矿石产品方案和选矿方法选择的框图,从而提供了一套完整的磷块岩矿石选矿评价预测技术。     

第七章 石棉选矿(续前)

第七章石棉选矿（续前）潘先佐（四川精维电解材料厂６１００８１）石棉选矿的目的，就是从石棉矿石中分离出纯净的石棉纤维，并按其纤维的不同长度进行分级。它与其他矿物选矿完全不同，它必须使用特别设计的专用机械设备和厂房。根据不同选矿方法，商品石棉可分为手选石...     

国内外硅灰石的选矿进展

全世界硅灰石的探明储量为1.6亿吨,1985年世界开采量达到25万吨。主要硅灰石生产国有美国、印度、芬兰和中国、我国又是硅灰石主要出口国,预计到2000年,我国硅灰石的年产量约15～20万吨,出口量达10万吨。硅灰石用于陶瓷、釉面砖、电焊条、油漆和橡胶工业,其中以在塑胶类物质中作填料及石棉代用品居多,目前国外正从事以硅灰石代替钛用于宇宙飞船保护壳和轴的研究。 一.国内外硅灰石选矿进展 铁和方解石是硅灰石中的有害组分,铁过高降低产品的白度,方解石过量引起坯体结构松驰。国外一般控制硅灰石中Fe_2O_3<     

高压辊磨机的特性及其在矿石选矿破碎中的应用

在进行矿石选矿的工作过程中,高压辊磨机是一种至关重要的机械设备,该设备对选矿磨碎效率与精度的提升有着重要作用。基于此,笔者对高压辊磨机在矿石选矿磨碎工作中的具体应用进行分析,以此来为该机械设备的应用和矿石、选矿工作质量的提升提供相应参考。     

磷矿的化学选矿

随着采选工业的发展,以及各工业部门对选矿产品在数量和质量上的要求日益提高,许多组成复杂、品位低、矿物细粒嵌布的矿石的选矿问题已成为极待解决的课题。对于此类矿石,采用基于单体颗粒分离的物理选矿方法,往往难以获得高质量的精矿,或者使有用矿物在尾矿中大量损失。对于某些矿石用物理选矿方法实际上不可能回收有     

硅灰石在不饱和聚酯树脂中的应用

对针状硅灰石（L：D≥10，325目及800目）提纯后，采用硅烷偶联剂进行表面处理，用活化指数对改性效果进行评价，确定了偶联剂的最佳用量，将硅灰石按不同比例填充于不饱和聚酯树脂体系中，研究了材料的性能，比较了不同粒径硅灰石对材料性能的改善效果。结果表明：改性后的硅灰石可显著改善不饱和聚酯的性能。800目硅灰石比325目硅灰石对不饱和聚酯树脂的性能改善效果更好。当800目硅灰石的添加量在30％－40％之间时，硅灰石填充不饱和聚酯复合体系经基体树脂的拉伸强度增加1．95倍，弯曲强度增加1．47倍。     

探讨复杂矿石及精矿湿法冶金工艺的进展

近年来,随着环境问题的日益恶化与严峻、能源问题不断涌现,矿山工作面临着巨大的挑战和机遇。目前,矿山和冶金工业在选矿之中致力于开发现代化的选矿措施,改善传统火法冶金工艺的处理难度和矿石的提炼要求,因此在工作之中对于复杂矿石及精矿的湿法冶金处理工艺变得越来越重要。选矿是目前矿山工作中的主要难题,其在工作中常常受到无法或难以将有份矿物分选为可以外销精矿的制约。因此在工作之中采用湿法冶金是利用选择性浸出工艺为基础,通过化学分选方式来对选矿工作中较为难选的矿石进行分类。本文以复杂矿石及精矿处理新技术的研发案例为依据分析,详细的介绍了阐述了回收混合硫化矿中铜、铂等金属的冶炼工艺。     

滑石微粉提纯的技术研究

天然滑石矿是多种矿物的集合体。原矿石可采用人工选矿进行提纯，但对于微粉颗粒人工选矿是无能为力的。利用滑石与伴生矿物杂质的物理性质的差异以及其在超细粉碎过程中不同的运动特性达到提纯的目的。得到的滑石，纯度明显提高，粒径分布窄，适宜作高档功能性粉体。     

云南尖山低品位磷矿特征研究及工业应用

对云南尖山磷矿堆存的低品位混合型磷块岩进行矿石特性研究，分析磷矿石的化学组分、矿物组成及结构、嵌布粒度、矿物单体解离特征及矿石可选性。通过实验室不同选矿工艺研究及对比，最终选择与碳酸盐型胶磷矿配矿浮选生产应用。配矿浮选采用反浮选一次粗选、一次精选、一次扫选工艺，可获得精矿w(P₂O₅) 28.04%、w(MgO) 0.93%、产率71.87%、P₂O₅回收率90.37%的选矿指标。     

光电选矿技术在沙特磷矿的应用

光电选矿是利用矿石和脉石的物性差异,通过对原矿进行逐粒扫描分析,将脉石与矿石分离以提高矿石品位的一种技术。本文介绍了光电选矿技术在沙特某磷矿选矿厂的应用,为我国低品位磷矿的预选提供了一条可以借鉴的路线。     

Crack-free silicate bioceramics from preceramic polymers

As a case study, the present paper illustrates an innovative processing method employing a preceramic polymer containing different fillers, which can be used to manufacture various ceramic components for biomedical applications. Crack-free wollastonite (CaSiO₃) ceramics were successfully produced, with high phase purity, after heating at 900°C in air starting from a silicone resin containing CaCO₃ micro-sized particles as ‘active filler’. As ‘passive filler’, wollastonite preceramised powders as well as commercially available wollastonite fibres were added. Their presence reduces the gas evolution occurring due to the decomposition of the calcium carbonate active filler and the polymer-to-ceramic conversion, reducing the stresses that generate in the component during heating. The resulting samples exhibited improvements in terms of the morphology and the mechanical strength, with respect to samples not containing any passive fillers, without significant modification of the final phase assemblage.     

Scratch deformation characteristics of micrometric wollastonite‐reinforced ethylene‐propylene copolymer composites

The scratch deformation behavior of neat and wollastonite‐containing ethylene‐propylene copolymer composites has been studied by electron microscopy and atomic force microscopy techniques. The study indicates that the severity of plastic deformation during scratch testing in reinforced ethylene‐propylene copolymers is a function of debonding/detachment of wollastonite mineral particles from the ethylene‐propylene matrix. The resistance to scratch deformation was evaluated in terms of scratch hardness, scratch depth, average scratch roughness, and change in gray level before and subsequent to scratching. The data suggests that resistance to scratch deformation follows the sequence: coated + coupled wollastonite‐containing EP copolymer > fine wollastonite‐containing EP copolymer > coated wollastonite‐containing EP copolymer > coarse wollastonite‐containing EP copolymer > neat EP copolymer. EP copolymer containing coated wollastonite and coupling agent is characterized by highest scratch hardness and minimum scratch depth and scratch roughness. The visibility of scratch, quantified in terms of gray level, suggests that coated + coupled wollastonite‐containing copolymer exhibits significantly reduced susceptibility to stress whitening, and is characterized by a lower gray level in the scratch‐deformed regions. In the present case of wollastonite‐containing copolymer composites, the resistance to scratch deformation follows a trend similar to that of gray level or scratch visibility. Polym. Eng. Sci. 44:1738–1748, 2004. © 2004 Society of Plastics Engineers.     

PBMA原位包覆硅灰石填充改性聚丙烯的研究

采用不同的方法处理硅灰石填充改性PP,研究了经不同处理工艺处理的硅灰石对PP复合材料力学性能及加工流动性的影响。结果表明:在相同用量下,经PBMA表面包覆方法处理的复合材料比偶联剂JN-101处理的屈服强度要高,同时经过表面包覆的硅灰石能使PP屈服强度提高45.9%。SEM分析表明:经表面包覆的硅灰石分散能力大幅度提高,与基体界面结合较好;复合材料的熔体流动速率随着包覆硅灰石添加量的增加而降低。     

Polymer nanocomposites for bone tissue substitutes

Following the quest for new composite biomaterials for bone tissue engineering, this work presents the processing of new nanocomposite made of polycaprolactone matrix and wollastonite particles. Wollastonite nanopowder was obtained by thermal treatment of polymethyloxosilane resin mixed with silica and calcium hydroxide. Bioactive character of the ceramic nanopowder was verified in simulated body fluid (SBF). The apatite formation on wollastonite grain surface after immersion in SBF was observed. Basic mechanical properties of the samples containing various amount of ceramic nanoparticles have been examined. It was shown that the presence of small amount of wollastonite nanoparticles (0.5–1.0 wt%) improves significantly the Young's modulus, tensile strength, and work-of-fracture of polymer matrix composite. Increased content of ceramic nanoadditive (>2%) in nanocomposites resulted in degradation of their mechanical characteristics.     

硅灰石作聚合物填料的应用及其加工技术

硅灰石用作聚合物填料可降低聚合物产品的成本,改善其性能,已成为硅灰石开发利用的重要方向。本文介绍了硅灰石的矿物学特性、国外硅灰石作为聚合物填料的应用及其加工技术。并对我国硅灰石填料的发展提出建议。     

硅灰石的深加工及在塑料工业中的应用

介绍了硅灰石的性能、深加工技术,及其硅灰石的深加工产品在尼龙、聚四氟乙烯、聚丙烯、聚乙烯等塑料中的应用效果。     

聚丙烯/硅灰石复合材料的改性

综述了近年来国内外关于硅灰石改性聚丙烯(PP)过程中表面处理、工艺条件对PP/硅灰石复合材料性能的影响以及硅灰石与乙烯辛烯共聚物（POE）、部分氢化聚苯乙烯丁二烯共聚物（SEBS）等材料复合改性PP的研究现状,并展望了PP/硅灰石复合材料的发展前景。     

硅灰石表面改性及其在丁苯橡胶中的应用

以硅灰石为原料，用干法改性优化出改性剂的种类，再用该改性剂，利用ZM振动磨探讨了硅灰石表面改性的工艺条件：当硬脂酸质量分数为2％、改性时间为9min、处理量占ZM振动磨容量的10％时，经沉降体积法、表面接触角法、红外光谱等方法及填充丁苯橡胶试验证实，硅灰石改性效果最佳；且填充丁苯橡胶物理机械性能有明显提高，试样拉伸强度增加，永久变形，邵尔A型硬度增大。     

我国硅灰石及其填充塑料的研究进展

综述了国内有关硅灰石填充塑料方面的工作，填充改性工艺的研究和对填充改性塑料性能的考察。研究发现，硅灰石/聚丙烯（PP）体系属非牛顿假塑性流体。熔体流动性接近或优于PP，这有利于加工稳定性的提高；硅灰石可以成为树脂的成核剂而对树脂的结晶行为和结晶度产生明显的影响。硅灰石填充塑料的力学性能一般较未填充体系有所改善，这可能归因于硅灰石所特有的针状晶体形态，另外，硅灰石填充于塑料中，可以使生产成本有较大幅度的下降，显示了明显的经济效益。     

In-vitro bioactivity of wollastonite materials derived from limestone and silica sand

This paper describes the behaviour of bioactive wollastonite materials containing Malaysian limestone and silica sand. Wollastonite, which is also known as calcium silicate (CaSiO₃), is an industrial mineral composed of calcium, silicon and oxygen. Pseudowollastonite, which is a primary crystal of wollastonite, was synthesised via a solid-state reaction at a temperature of 1450 °C. The in-vitro bioactivity of wollastonite was examined by soaking it in simulated body fluid (SBF) solution for 1–7 days at 36.5 °C. The soaked wollastonite samples were characterised using XRD, SEM-EDX, FTIR and ICP analyses. Apatite particles precipitated on the surface of the wollastonite sample after the sample was soaked in the SBF. The XRD analysis indicated the presence of an increasing amount of the hydroxyapatite phase as the soaking time increased. The SEM and EDX analyses indicated the formation of granules of agglomerated apatite particles on the surface of the soaked wollastonite sample. During the formation of apatite, phosphate ions from the SBF solution were consumed. This process was confirmed by ICP, which revealed a decrease in ion concentration after the soaking process. The FTIR analysis indicated that the peaks of the phosphate ions increase when the apatite layer forms on the surface of the wollastonite sample. After the soaking process, a calcium deficient hydroxyapatite layer was observed on the wollastonite sample. The study concludes that wollastonite produced from Malaysian limestone and silica sand is bioactive and may be used as an implantable biomaterial.