【作者】 杜长学；

【导师】 彭振斌； 杨传德；

【作者基本信息】 中南大学 ， 地质工程， 2006， 博士

【摘要】 矿泥是氧化铝生产过程中在洗、选矿时排出的高含水量红色粘土状物质。国内对矿泥的处理主要采用管道输送、湿法堆存，其优点是堆场运行管理简单，矿泥排放和堆存无特殊要求。但湿法堆存占用大量土地，附碱损失高，防渗处理困难，对环境存在潜在的危害。广西平果铝矿自1995年投产以来，堆存矿泥逾1000万m³，且在以4000m³／d的速度增加。大量矿泥的弃置不用既造成资源浪费，又增加了企业的生产成本。 本文通过原位测试、室内土工试验、能谱分析、x射线物相分析、等离子光谱、扫描电镜观察及固化试验等方法对矿泥的沉积规律、物理力学性质、化学特性、固化剂筛选、固化机理等进行深入的研究。在此基础上，对固化矿泥的应用作了有益的探讨。 平果铝矿泥颗粒细小、表面积大、颗粒表面带电，粘性差。矿泥在沉积时由于受粒度、流速、放矿方法和矿浆浓度的综合影响，矿泥的沉积形成了三个区：冲积滩的水上区、冲积滩的水下斜坡区和沉淀池区。由于自身的特性和沉积规律，矿泥在沉积时形成“超架空结构”微观结构，由此导致了矿泥的含水量可超过100％；十字板抗剪强度不超过58.2kPa；压缩系数α_1-2界于0.20～1.85MPa^-1之间；液限平均值为43.8％，塑性指数Ip平均值为17.8，液性指数I_L平均值为1.74，矿泥处于流塑～软塑状态；渗透系数k平均值为2.44×10^-6cm／s，而矿泥在100～800kPa荷载下，固结系数为0.27～7.16×10^-3cm²／s；矿泥持水量为79～93％，震动析水量为4.7～14.9％。因而矿泥在自然条件下难以排水泌干，完成自重固结需要上百年的时间。 针对平果铝矿泥含铁、铝高，硅、钙低的特点，对其进行了固化剂配方筛选研究，研究发现平果铝矿泥有两组较好的固化配方：①水泥72％、石膏20％、石灰5％、硫酸钠3％，②石灰72％、石膏20％、粉煤灰5％、硫酸钠3％。且配方②的固化效果较配方①好，材料也更经济。 通过能谱分析、x射线物相分析、等离子光谱、扫描电镜观察等方法对矿泥固化过程进行进一步研究，结果发现固化过程发生的一系列复杂的物理、化学和物理化学反应，可归结为以下方面：水解反应、离子交换和团粒化作用、硬凝反应、火山灰反应、碳酸化作用和结晶作用。反应的主要生成物是水化硅酸钙、水化铝酸钙、结更多还原

【Abstract】 Bauxite mine slime is the high water content and red clay material that discharged during product Alumina, The main method to deal with it in China is transporting by pipe and storing up it as it is nature, its advantage is that the operation of storage yard to manage is simple, the bauxite mine slime emission and store up without special requirement, but it occupy plenty of lands as it store up in nature, the soda attached is lost easily. Defence seeps handling is difficult, and it have latent harm for environment. GuangXi PingGuo Aluminum Industry Company have stored up bauxite mine slime exceed 1000x10⁴m³ since it started product alumina in 1995, and is increasing with the speed of 4000 m³/d . Plenty of bauxite mine slime put aside to do not need cause resource waste, and have again increased the production cost of company.Using site testing and geotechnial testing indoor, X-ray Energy Dispersive Analysis（EDAX）, X-ray diffraction phase analysis, Inductively Coupled Plasma-Atomic Emission Spectrometry（ICP-AES）, Scanning Electron Microscopy（SEM） and bauxite mine slime solidified experiment etc, we study the physical mechanics chemical property, curing agent test and selection, the solidified mechanism of bauxite mine slime. On this foundation we discuss the application of solidified bauxite mine slime.The pellet of the bauxite mine slime discharged by GuangXi PingGuo Aluminum Mine Company are small, the surface of the pellet is big, pellet surface electrified, and there is not glued between pellets. There are three areas when bauxite mine slime deposited because of pellet size , current velocity , put mine slime method and the density of bauxite mine slime. The three areas are: alluviation beach district above the water, alluviation beach district under the water and deposit area. Because of deposit law and the property of itself, bauxite mine slime forms the " Super Impracticable Structure" microscopic structure when it is depositing. By this, the water content of bauxite mine slime exceed 100%, cross shear strength does not exceed 58.2kPa, reduce coefficient α_1-2 are between 020 MPa^-1 and1.85MPa^-1, liquid limit is 43.8%, plasticity更多还原