河南不同成因类型铝土矿的矿石特征

本文在对铝土矿石物质组成研究的基础上,运用电子显微镜(EM)对河南两类不同类型铝土矿床的矿石结构进行了观察研究。根据EM观察到的铝土矿石显微结构的不同形貌特征,划分出三种矿石结构类型:致密-隐晶结构、粒状镶嵌结构和粒屑结构。由此归结为两个成因类型:古风化壳异地堆积亚型和古风化壳原地堆积亚型的铝土矿床。     

华北铝土矿矿石分类

在铝土矿矿石结构分类（粗糙状、碎屑状、鲕豆状和致密状）的基础上，根据拜尔法工艺对矿石的要求，按矿石中主要组分的种类及其含量进一步划分为正常型、高岭石型、伊利石型、绿泥石型和混合型五个亚类。利用矿石中的Ａｌ２Ｏ３、ＳｉＯ２、Ｋ２Ｏ、Ｆｅ２Ｏ３和ＴｉＯ２，根据Ｑ型聚类分析划分了三种化学成分类型。对不同矿石类型的可用性提出了结论性意见。     

铝土矿赤泥的开发利用

赤泥耕层土是一种大量消纳赤泥,同时又将其转化为二次资源的赤泥产品。该技术以农作物废弃物为改性剂,通过改性剂在赤泥中发酵腐化的产物改性赤泥成适宜植物生长的土壤。该技术应用不受赤泥组分、结构差异等因素限制,具有广泛适用性,尤其是有价金属元素含量低、又不适宜于制作建材的赤泥以及堆场防渗、防溃（堤）能力弱,需迅速消减的赤泥库的赤泥土可优先选用该技术处理。     

贵州道真县大塘铝土矿沉积相特征

文章通过对含矿岩系岩石、矿物、微量元素及沉积特征的阐述,概括了贵州道真县大塘铝土矿的沉积相特征并对铝土矿沉积环境进行了探讨。     

西澳Darling Range地区铝土矿特征及成矿控制因素

我国铝土矿资源相对匮乏,但需求量大。澳大利亚铝土矿资源丰富,是我国铝土矿进口主要国家之一。Darling Range地区为澳大利亚铝土矿主产地之一,了解该区的铝土矿成矿特征将有助于我国企业走出去在该地区或相似地区找矿提供依据。Darling Range位于西澳大利亚的伊尔岗克拉通,该区铝土矿以红土型为主,铝土矿的显著特点是品位较低,铁、硅含量高,但对铝土矿冶炼有害的可溶性硅含量低,资源潜力巨大。铝土矿产于红土层中,厚度受后期剥蚀作用控制。红土剖面从上到下依次分为覆盖层、硬壳、碎屑层和底部粘土层。覆盖层以砂砾为主,具有经济意义的铝土矿主要集中在碎屑层和硬壳中,底部粘土层则阻止铝土矿继续向下运移。铝土矿中的矿石矿物主要是三水铝石,也有少量一水软铝石,主要由花岗岩或基性岩(如辉绿岩、绿岩)中的长石经过风化淋滤形成。Darling Range地区铝土矿根据基岩的种类可分为花岗岩类铝土矿和镁铁质类铝土矿,分别以Jarrahdale铝土矿矿床和Mount Saddleback铝土矿矿床为代表。铝土矿的成矿主要受气候、母岩、地貌、排水和植被等因素控制。气候主要通过控制气温和降水影响红土化作用的进行;母岩通过自身的物理化学性质和矿物组成控制铝土矿的形成;地貌和排水影响铝土矿的风化速度;植被的作用既保证了土壤风化淋滤所需的渗透性,又降低了外部因素对土壤的侵蚀速率。在各种成矿因素的综合作用下,经过漫长的时间演化最终形成了红土型铝土矿。     

红土型三水铝土矿的一种新分类方法

由于已知国内的红土型三水铝土矿矿床均为小型,且矿石质量也偏差,多为小规模开采利用,而国外多为大型—特大型矿床,质量也好.笔者长期在境外开展红土型三水铝土矿的资源勘探和资源评价工作.在结合矿山开采的选矿工作和生产氧化铝的拜耳法工艺,对红土型三水铝土矿按照边界品位即是否需要洗矿,提出了全新的分类方法.     

Mineralogical and geochemical investigations of the Mombi bauxite deposit,Zagros Mountains,Iran

The Mombi bauxite deposit is located in 165 km northwest of Dehdasht city, southwestern Iran. The deposit is situated in the Zagros Simply Fold Belt and developed as discontinuous stratified layers in Upper Cretaceous carbonates (Sarvak Formation). Outcrops of the bauxitic horizons occur in NW-SE trending Bangestan anticline and are situated between the marine neritic limestones of the Ilam and Sarvak Formations. From the bottom to top, the deposit is generally consisting of brown, gray, pink, pisolitic, red, and yellow bauxite horizons. Boehmite, diaspore, kaolinite, and hematite are the major mineral components, while gibbsite, goethite, anatase, rutile, pyrite, chlorite, quartz, as well as feldspar occur to a lesser extent. The Eh–pH conditions during bauxitization in the Mombi bauxite deposit show oxidizing to reducing conditions during the Upper Cretaceous. This feature seems to be general and had a significant effect on the mineral composition of Cretaceous bauxite deposits in the Zagros fold belt. Geochemical data show that Al₂O₃, SiO₂, Fe₂O₃ and TiO₂ are the main components in the bauxite ores at Mombi and immobile elements like Al, Ti, Nb, Zr, Hf, Cr, Ta, Y, and Th were enriched while Rb, Ba, K, Sr, and P were depleted during the bauxitization process. Chondrite-normalized REE pattern in the bauxite ores indicate REE enrichment (ΣREE = 162.8–755.28 ppm, ave. ∼399.36 ppm) relative to argillic limestone (ΣREE = 76.26–84.03 ppm, ave. ∼80.145 ppm) and Sarvak Formation (ΣREE = 40.15 ppm). The REE patterns also reflect enrichment in LREE relative to HREE. Both positive and negative Ce anomalies (0.48–2.0) are observed in the Mombi bauxite horizons. These anomalies are related to the change of oxidation state of Ce (from Ce³⁺ to Ce⁴⁺), ionic potential, and complexation of Ce⁴⁺ with carbonate compounds in the studied horizons. It seems that the variations in the chemistry of ore-forming solutions (e.g., Eh and pH), function of carbonate host rock as a geochemical barrier, and leaching degree of lanthanide-bearing minerals are the most important controlling factors in the distribution and concentration of REEs. Several lines of evidences such as Zr/Hf and Nb/Ta ratios as well as similarity in REE patterns indicate that the underlying marly limestone (Sarvak Formation) could be considered as the source of bauxite horizons. Based on mineralogical and geochemical data, it could be inferred that the Mombi deposit has been formed in a karstic environment during karstification and weathering of the Sarvak limy Formation.     

广西铝土矿遥感综合成矿预测及资源总量估算

前人在已知矿床、点的基础上对广西铝土矿做过系统的成矿预测及资源总量估算，但原有工作限于储量级别要求，划入预测区的范围较小，部分有矿层分布的区带未圈出，又参与资源总量估算的块段尚有向外延伸部分。通过遥感综合方法，在原有基础上扩大预测区，增加三水型铝土矿预到区，并对已知块段外延矿带、新增预测区进一步估算其资源总量，较全面地解决了资料不完整地区的铝土矿资源量估算问题。     

平果铝土矿样品加工粒度的研究

为使样品加工粒度200目的过筛率平均达到98％以上，满足X荧光分析对样品粒度的基本要求，在实验过程中发现了饭颗粒存在并影响着过筛率，通过分析饭颗粒的成因，找出了有效抑制饭颗粒的办法——加入酒精在一定的条件下能抑制饭颗粒的产生并能保证样品加工粒度达到200目过筛率平均在98％以上。     

铝土矿加压法生产硫酸铝的工艺研究

研究了铝土矿与硫酸进行加压反应制造硫酸铝的生产工艺，确立了最优工艺操作条件。当采用适当的矿粉粒度、硫酸浓度、原料配比、反应压力进行生产时，反应平稳，铝士矿的铝溶出率高。适当的矿渣洗涤次数可以使铝土矿的铝利用率得到提高。将本研究成果应用于生产实际，充分利用了矿产资源，节约了能源，从而降低了生产成本，达到了节能降耗的目的。