硅灰石

硅灰石是一种新型的陶瓷原料,能满足于低温快速一次烧成的工艺要求,产品具有光洁、坚固、湿膨胀低、干燥收缩小、成型好、化学惰性强、介电损耗低等特点。硅灰石还可用作涂料、塑料、橡胶、磨料、焊条、釉面砖坯体和绝缘材料等。在国外许多国家都发现了硅灰石。苏联发现的硅灰石,是产在前寒武纪地层中。印度的硅灰石储量也很大。我国在前寒武纪和古生代地层中发现了硅灰石矿。     

吉林省的优质硅灰石矿

硅灰石用于陶瓷、涂料、塑料、橡胶、磨料、焊条、绝缘材料等工业,尤其是釉面砖坯体的理想原料。硅灰石能满足低温快速一次烧成的工艺要求,具有光洁、坚固、湿膨胀低、干燥收缩小、成型性好、化学惰性强、介电损耗低等特点。目前很多国家在建陶工业中广泛使用硅灰石。 吉林省磐石县长葳子硅灰石矿床是吉林省地质局第一地质队勘探的。矿床产在燕山期花岗岩与上古生代硅质灰岩和含燧石条带灰岩接触带上。属矽卡岩型矿床。主要矿体     

硅灰石与方解石、石英分选工艺研究的新成果

吉林省地矿局于1987年5月15—16日组织省内外专家对吉林省地质实验研究中心完成的“硅灰石与方解石、石英分选工艺——大顶山低品位硅灰石综合回收”成果进行了技术评审,认为该项成果具有国内先进水平。该课题仅用十个月时间,提前一年多取得了可靠数据,全面完成了吉林省地矿局下达的科研任务。采用方解石、石英依次优先浮选流程,工艺合理、技术可行,指标先进,研制的w—50捕收剂分选硅灰石与     

吉林省硅灰石矿床成矿地质条件及成矿规律分析

硅灰石是一种天然产出的钙的偏硅酸盐类矿物[CaSiO3]具有一系列优异的物化特征和独特的工艺性能,主要应用在造纸、陶瓷、塑料、涂料、冶金、绝缘材料等领域,在节约能源"降低成本方面具有独特优势。随着科技的发展,应用范围不断地扩大。硅灰石是吉林省最具优势的非金属矿产资源之一,且找矿潜力很大,通过我省硅灰石矿床找矿标志及成矿规律研究,对指导硅灰石勘查及深部找矿,满足市场日益增长的需要具有重要意义。     

赣西蒙山地区石竹山超大型硅灰石矿床地质特征及找矿意义

江西省新余市石竹山硅灰石矿床硅灰石矿物量5 400余万t,相当于54个大型硅灰石矿床资源量规模,硅灰石矿物含量平均约60%。Ⅱ、Ⅷ号矿体为石竹矿区内主矿体。Ⅱ号矿体走向延伸超过4 800 m,倾向延深超过1300m,平均厚度14.14m,硅灰石平均含量60.86%,矿石类型以硅灰石-石英-方解石型(Ⅱ号矿体)为主。Ⅷ号矿体走向延伸超1 000 m,倾向延深超过600 m;平均厚度14.67 m;硅灰石矿物量600余万吨,硅灰石平均含量61.80%,矿石类型主要为硅灰石-透辉石型。蒙山地区"岩体+碳酸盐岩+构造裂隙+盖层"组合的矽卡岩与矽卡岩化大理岩化蚀变带是寻找硅灰石矿体的重要区域;石竹山—库里一带中深部具有寻找锡铜钨多金属矿的较好潜能。     

机械力化学改性硅灰石机理研究

天然硅灰石矿物具有特殊的针状结构,白色,无毒,是橡胶、塑料的理想填料。添加硅灰石填料,可降低橡胶制品的生产成本,提高橡胶的力学性能,赋以橡胶自身所没有的特殊功能。其作用大小取决于硅灰石／橡胶界面的结合状态。硅灰石系亲水性矿物,与橡胶相容性差。界面能否形成良好的粘结,硅灰石矿物表面性能是关键。经超细粉碎、表面改性可以提高硅灰石表面活性,增强与橡胶的粘结强度。但是,当硅灰石经超细粉碎,粒度为微米级或纳米级,粉体容重为０－１５ｇｃｍ３,以表面化学改性方法加入偶联剂,经高温高速搅拌,不但破坏硅灰石的长…     

江西蒙山地区石竹山—樟木桥矿区硅灰石地质特征及成因探讨

石竹山—樟木桥矿区硅灰石矿床是江西蒙山地区硅灰石矿田的重要组成部分,位于蒙山岩体南部,普查发现为一超大型硅灰石矿床。本文阐述了该硅灰石矿床的地质特征,从成矿物质来源、成矿物理化学环境等方面探讨了矿床成因,并建立了成矿模式,对今后蒙山地区的找矿工作具有指导意义。     

硅灰石的矿床类型和用途

一、前言硅灰石是具有多种变体的钙质偏硅酸盐(CaSiO_3)矿物。在自然界常温常压下稳定的只有低温变体中的三斜和单斜硅灰石,而硅灰石的高温变体仅见于人工合成和煤层地下燃烧的产物中。天然纯硅灰石(CaO48.3％和SiO_251.7％)甚为少见。由于它与钙蔷薇辉石的晶格相似,所以常受到Fe、Mn、Ti等杂质的混染、从而使其在工业上的应用受到很大的限制。     

吉林省硅灰石资源开发利用现状及展望

通过对吉林省硅灰石矿产资源开发利用现状及存在问题的分析,结合国內外硅灰石产需形势、硅灰石应用方向及技术标准,展望了硅灰石开发利用的市场发展趋势。     

吉林省磐石地区硅灰石成矿条件及找矿远景分析

在总结磐石地区已知四个大型硅灰石矿床长崴子硅灰石矿、孟家硅灰石矿、驿马乡西错草和南错草硅灰石矿地质特征的基础上,总结磐石地区硅灰石矿成矿地质条件,分析找矿前景.硅灰石主要产于石炭纪、奥陶纪的硅质碳酸盐岩建造中,构造为北西向断裂构造,与之关系密切的侵入岩以燕山期酸性岩为主.硅灰石矿成因类型主要为层控热接触变质型和层控热接触变质-接触交代变质型.磐石地区北部长崴子、孟家和东部驿马乡错草一带是硅灰石重点找矿远景区.     

Formation of wollastonite-bearing marbles during late regional metamorphic channelled fluid flow in the Upper Calcsilicate Unit of the Reynolds Range Group,central Australia*

Abstract Granulite facies marbles from the Upper Calcsilicate Unit of the Reynolds Range, central Australia, contain metre-scale wollastonite-bearing layers formed by infiltration of water-rich (X_CO2= 0.1–0.3) fluids close to the peak of regional metamorphism at c. 700° C. Within the wollastonite marbles, zones that contain <10% wollastonite alternate on a millimetre scale with zones containing up to 66% wollastonite. Adjacent wollastonite-free marbles contain up to 11% quartz that is uniformly distributed. This suggests that, although some wollastonite formed by the reaction calcite + quartz = wollastonite + CO₂, the wollastonite-rich zones also underwent silica metasomatism. Time-integrated fluid fluxes required to cause silica metasomatism are one to two orders of magnitude higher than those required to hydrate the rocks, implying that time-integrated fluid fluxes varied markedly on a millimetre scale. Interlayered millimetre -to centimetre-thick marls within the wollastonite marbles contain calcite + quartz without wollastonite. These marls were probably not infiltrated by significant volumes of water-rich fluids, providing further evidence of local fluid channelling. Zones dominated by grandite garnet at the margins of the marl layers and marbles in the wollastonite-bearing rocks probably formed by Fe metasomatism, and may record even higher fluid fluxes. The fluid flow also reset stable isotope ratios. The wollastonite marbles have average calcite (Cc) δ¹⁸O values of 15.4 ± 1.6% that are lower than the average δ¹⁸O(Cc) value of wollastonite-free marbles (c. 17.2 ± 1.2%). δ¹³C(Cc) values for the wollastonite marbles vary from 0.4% to as low as -5.3%, and correlations between δ¹⁸O(Cc) and δ¹³C(Cc) values probably result from the combination of fluid infiltration and devolatilization. Fluids were probably derived from aluminous pegmatites, and the pattern of mineralogical and stable isotope resetting implies that fluid flow was largely parallel to strike.     

Reciprocity Effect between Silicate Bacteria and Wollastonite

This paper studied the reciprocity effect between wollastonite and a strain silicate bacterium from purple soil. We analyzed the changes of pH value, glucose (GLU) residual concentration, electrolyte and Mn, Si, Fe etc. in the culture liquid with wollastonite after 48 h. The results show that the GLU wastage of silicate bacteria with wollastonite is 2.5 times of the bacterial contrast. It showed wollastonite could obviously accelerate silicate bacteria growth, but bacterial cell broken and distorted badly have been found by SEM analysis. The solubilization of silicate bacteria to Si element of wollastonite reached above 10 times. At the same time, three apices in FTIR of wollastonite (898 cm-1, 925 cm-1, 962 cm-1) descended obviously after the action of silicate bacteria, which shows that a great deal of Si has dissolved out. So we can get that wollastonite has remarkable effect to the growth of silicate bacteria and silicate bacteria has obvious solubilization to Si of wollastonite.     

Long-term interaction of wollastonite with acid mine water and effects on arsenic and metal removal

This paper reports the results of a laboratory experiment conducted to investigate the effects of wollastonite dissolution on removal of potentially toxic trace elements from stream waters affected by acid mine drainage (AMD). Nearly pure wollastonite was treated with natural acid mine water (pH 2.1) for different lengths of time (15, 30, 50 and 80 days). The compositional and textural characterization of the solid reaction products suggests that wollastonite was incongruently dissolved leaving a residual amorphous silica-rich phase that preserved the prismatic morphology of the parent wollastonite. The release of Ca into solution resulted in a pH increase from 2.1 to 3.5, and subsequent precipitation of gypsum as well as poorly crystallized Fe–Al oxy-hydroxides and oxy-hydroxysulfates whose components derived from the AMD solution. A geochemical modeling approach of the wollastonite–AMD interaction using the PHREEQC code indicated supersaturation with respect to schwertmannite (saturation index = 10.7–15.7), jarosite (SI = 8.7–10.2), alunite (SI = 5.1), goethite (SI = 4.7) and jurbanite (SI = 2.2). These secondary phases developed a thin coating on the reacted wollastonite surface, readily cracked and flaked off upon drying, that acted as a sink for trace elements, especially As, Cu and Zn, as indicated by their enrichment relative to the starting wollastonite. At such low pH values, adsorption of As oxyanions on the positively charged solid particles and coprecipitation of metals (mainly Cu and Zn) with the newly formed Fe oxy-hydroxides and oxy-hydroxysulfates seem to be the dominant processes controlling the removal of trace elements.     

Calc-silicate reactions and bedding-controlled isotopic exchange in the Notch Peak aureole, Utah: implications for differential fluid fluxes with metamorphic grade

Fluid compositions and bedding‐scale patterns of fluid flow during contact metamorphism of the Weeks Formation in the Notch Peak aureole, Utah, were determined from mineralogy and stable isotope compositions. The Weeks Formation contains calc‐silicate and nearly pure carbonate layers that are interbedded on centimetre to decimetre scales. The prograde metamorphic sequence is characterized by the appearance of phlogopite, diopside, and wollastonite. By accounting for the solution properties of Fe, it is shown that the tremolite stability field was very narrow and perhaps absent in the prograde sequence. Unshifted oxygen and carbon isotopic ratios in calcite and silicate minerals at all grades, except above the wollastonite isograd, show that there was little to no infiltration of disequilibrium fluids. The fluid composition is poorly constrained, but X(CO₂)_fluid must have been >0.1, as indicated by the absence of talc, and has probably increased with progress of decarbonation reactions. The occurrence of scapolite and oxidation of graphite in calc‐silicate beds of the upper diopside zone provide the first evidence for limited infiltration of external aqueous fluids. Significantly larger amounts of aqueous fluid infiltrated the wollastonite zone. The aqueous fluids are recorded by the presence of vesuvianite, large decreases in δ¹⁸O values of silicate minerals from c. 16‰ in the diopside zone to c. 10‰ in the wollastonite zone, and extensive oxidation of graphite. The carbonate beds interacted with the fluids only along margins where graphite was destroyed, calcite coarsened, and isotopic ratios shifted. The wollastonite isograd represents a boundary between a high aqueous fluid‐flux region on its higher‐grade side and a low fluid‐flux region on its lower‐grade side. Preferential flow of aqueous fluids within the wollastonite zone was promoted by permeability created by the wollastonite‐forming reaction and the natural tendency of fluids to flow upward and down‐temperature near the intrusion‐wall rock contact.     

广西平乐硅灰石矿工艺矿物学研究

对广西平乐硅灰石矿的化学成分和矿物组成进行了分析确定，对硅灰石及其伴生矿物的结构构造特征进行了查定，主要对硅灰石中碳质物的赋存特征进行了研究，发现硅灰石矿石中的碳质物分别与硅灰石、方解石、石英等多种矿物以多种形式紧密伴生，认为要提高平乐硅灰石粉的白度，除了要尽可能除去透辉石、石榴石等矿物杂质及含铁、锰等的氧化物杂质外，关键还要使碳质物单体解离，并除去碳质物杂质。     

广西南源洞硅灰石中石墨的赋存特征及其对硅灰石粉白度的影响

采用X射线衍射（XRD）及扫描电子显微镜（SEM）等方法对广西南源洞以层控接触热变质作用为主，并伴随有接触交代作用的叠加所形成的硅灰石矿石中的黑色碳质物的物相及存在特征进行了研究。发现硅灰石矿石中的碳质物为石墨，并分别与多种矿物紧密伴生，伴生情况有几种：（1）碳质物与硅灰石、方解石紧密伴生；（2）碳质物与石英、方解石紧密伴生；（3）碳质物仅与方解石紧密伴生；（4）碳质物呈尘埃状或星点状被包裹于硅灰石矿物颗粒中；（5）碳质物以浸染、渗透方式存在于硅灰石矿物颗粒中。欲将碳质物从硅灰石矿物中解离出来，至少要将矿石粉碎到0.043mm以下。另外，还就硅灰石中的碳质物对于硅灰石粉白度的影响进行了讨论。     

Patterns of Ca/Sr and Sr/Sr variation before and after a whole watershed CaSiO3 addition at the Hubbard Brook Experimental Forest, USA

Forty-one metric tons of the mineral wollastonite (CaSiO₃) was applied to an 11.8 hectare watershed at the Hubbard Brook Experimental Forest (HBEF; White Mountains, New Hampshire, USA) with the goal of restoring the Ca estimated to have been depleted from the soil exchange complex by acid deposition. This experiment provided an opportunity to gain qualitative information on whole watershed hydrologic flow paths by studying the response of stream water chemistry to the addition of Ca. Because the Ca/Sr and ⁸⁷Sr/⁸⁶Sr ratios of wollastonite strongly contrast that of other Ca sources in the watershed, the wollastonite-derived Ca can be identified and its amount estimated in various ecosystem components. Stream water chemistry at the HBEF varies seasonally due to shifts in the proportion of base flow and interflow. Prior to the wollastonite application, seasonal variations in ⁸⁷Sr/⁸⁶Sr ratios indicated that ⁸⁷Sr/⁸⁶Sr was higher during base flow than interflow, due largely to greater amounts of biotite weathering along deeper flow paths. After the application, Ca/Sr and ⁸⁷Sr/⁸⁶Sr changed markedly as the high Ca/Sr and low ⁸⁷Sr/⁸⁶Sr wollastonite dissolved and mixed with stream water. The Ca addition provided information on the response times of various flow paths and ion exchange processes to Ca addition in this small upland watershed. During the first year after the addition, wollastonite applied to the near stream zone dissolved and was partially immobilized by cation exchange sites in the hyporheic zone. In the second and third years after the addition we infer that much of this Ca and Sr was subsequently desorbed from the hyporheic zone and was exported from the watershed in stream flow. In the fourth through ninth years after the addition, Ca and Sr from wollastonite that had dissolved in upland soils was transported to the stream by interflow during wet periods when the ground water table was elevated. Between years three and nine the minimum annual Ca/Sr ratio (in late summer base flow) increased, providing evidence that Ca and Sr had increasingly infiltrated to the deepest flow paths. Strong seasonal variations in Ca/Sr and ⁸⁷Sr/⁸⁶Sr ratios of stream water resulted from the wollastonite addition to upland forest soils, and these ratios have become sensitive to changing flow paths during the annual cycle. Most notably, high flow events now produce large excursions in stream geochemistry toward the high Ca/Sr and low ⁸⁷Sr/⁸⁶Sr ratios of wollastonite. Nine years after the application we estimate that ∼360 kg of Ca from wollastonite has been exported from the watershed in stream flow. The rate of export of Ca from wollastonite dissolution has stabilized at about 11 kg of Ca per year, which accounts for ∼30% of the dissolved Ca in the stream water. Given that 19 metric tons of Ca were applied to the watershed, and assuming this current rate of loss, it should take over 1000 years for this added Ca to be transported from the watershed.     

甘肃北山金庙沟南大型硅灰石矿床地质特征及找矿标志

甘肃省肃北县金庙沟南硅灰石矿床产于敦煌岩群C岩组三岩段的石英硅灰大理岩与花岗岩的接触带及其附近，矿体呈透镜状、似层状产出。矿区共圈出硅灰石矿体16个，矿体长96~818 m，矿体厚度在1.20~12.33 m之间，矿石品位为φ（硅灰石）=35.53%~51.62%，含矿岩石为石英硅灰石大理岩。矿石的类型可分为团块状硅灰石-方解石-石英型矿石、薄层状硅灰石-方解石-石英型矿石。在矿床地质特征研究的基础上，对矿床成因类型进行了分析，提出了找矿标志，对甘肃北山寻找同类矿床具有借鉴意义。     

纤维状硅灰石/聚丙烯复合材料界面性能研究

以未改性纤维状硅灰石粉、硬脂酸改性纤维状硅灰石粉与聚丙烯混炼制成聚丙烯复合材料。利用平衡接触角仪间接测得聚丙烯基体和矿物粉体的表面自由能。计算出纤维状硅灰石／聚丙烯界面的粘附功Wa和界面张力γSL等热力学参数。分析探讨了聚丙烯及矿物粉体表面特性、纤维状硅灰石／聚丙烯界面行为与复合材料力学性能的关系。结果表明：复合两相界面的粘附功Wa和界面张力γSL,共同作用影响复合材料的强度。界面粘附功Wa大,说明两相结合牢固．则复合材料强度大;界面张力γSL小。则粉体在基体中的分散性能好,有利于增加两相间总的接触面积,使复合材料强度增大。研究复合两相的界面行为．找出粘附功Wa和界面张力γSL间的最佳组合。将有助于设计出性能优良的复合材料。为合理地选择和改性填料提供科学依据。