天然碱开采水平溶腔发育关键影响因素及稳定性分析

发布时间：2018-03-08 08:21

  本文选题：天然碱　切入点：水平对接井　出处：《中国地质大学(北京)》2017年硕士论文　论文类型：学位论文

【摘要】：水溶法采矿是根据某些矿物易溶于水的特性而发展形成的一种重要的采矿方法,具有投入成本低、劳动强度低和安全环保等许多优点,其主要分类有:硐室水溶开采和钻井水溶开采(单井和井组生产)两种方法,其中井组水溶开采根据开采工艺又分为自然连通、压裂连通和水平对接连通井三种方法。水溶采矿技术的发展日新月异,此方法最初广泛应用在开采地下岩盐矿藏,后随着技术的成熟逐步应用于开采钾盐矿、芒硝矿、天然碱矿等矿藏。本文以《土耳其Kazan天然碱溶采项目地下工程》水平对接井技术溶采天然碱为背景,对影响天然碱开采卤水浓度和总碱度的影响因素通过理论和试验数据做了部分分析研究,以及利用水平溶腔简化模型,通过数值模拟软件,对天然碱水平溶腔发育过程中溶腔稳定性及安全矿柱做了简单的研究。利用水平对接井开采天然碱过程中,天然碱矿石的溶解过程是一个很复杂的过程,影响卤水浓度的因素也有很多,例如:矿石品味、溶剂条件、开采技术手段和溶腔形状等。本文主要通过天然碱理论溶解特性对比kazan试采井现场采集的实验数据,从溶剂注入温度、溶剂注入流量和溶剂配比以及开采技术手段这些可控因素方面入手,对其影响天然碱卤水浓度和总碱度的具体情况做出分析。随着天然碱矿床的开采,水平溶腔的发育也是关注的一个重点,因为水平溶腔的形状和大小也是影响卤水浓度的一个重要因素,此外,水溶采矿过程中溶腔的发育稳定性也是很重要的关键因素。随着溶腔腔体发展变大,溶腔围岩由于卸荷扰动,原有应力状态发生变化,岩体内应力发生重分布,产生位移变形,当岩体应力大于其屈服强度后,就会发生破坏,所以,为了防止由于大规模的垮塌变形造成堵塞溶腔通道进行修井和破坏生产套管及中心油管的情况发生,了解溶腔发育过程中溶腔周围岩体应力和应变分布情况及破坏范围是很有必要的,同时,研究水平溶腔围岩稳定性对布井设计时预留矿柱的大小也有重要的指导意义。本文以kazan天然碱矿区地质条件为背景,利用FLAC3D软件建立简化模型,模拟不同规模水平溶腔围岩的应力分布和应变情况,希望能给卡赞天然碱矿的开采带来力所能及的帮助。
[Abstract]:Water solution mining is an important mining method developed according to the characteristics of some minerals that are soluble in water. It has many advantages, such as low input cost, low labor intensity, safety and environmental protection, etc. The main classification is as follows: chamber water solution mining and drilling water solution production (single well and well group production), in which the well group water solution mining is divided into natural connectivity according to the mining technology. The development of water-soluble mining technology is changing with each passing day. This method was widely used in mining underground rock salt deposits at first, and then gradually applied to mining potash ore with the maturity of technology. The background of this paper is "Underground Engineering of Kazan Natural Alkali dissolution Mining Project", horizontal docking well technology, dissolution and production of natural alkali. The influence factors on the concentration and total alkalinity of brine in natural alkali mining are studied in part through theoretical and experimental data, and the simplified model of horizontal solution cavity is used, and the numerical simulation software is used to analyze and study the factors affecting the concentration and total alkalinity of the brine. The stability of the cavities and the safety of ore pillars during the development of horizontal solution cavities are studied. The dissolution process of natural alkali ores is a very complicated process during the exploitation of natural alkali by horizontal docking wells. There are many factors that affect the concentration of brine, such as ore taste, solvent condition, extraction technology and cavity shape, etc. Based on the controllable factors of solvent injection temperature, solvent injection flow rate, solvent ratio and mining technology, this paper analyzes the specific conditions that affect the concentration and total alkalinity of natural alkali brine. The development of horizontal cavities is also a key concern, because the shape and size of horizontal cavities are also an important factor affecting the concentration of brine. The development and stability of the cavity is also a very important factor in the process of water solution mining. With the development of the cavity, the original stress state changes due to the unloading disturbance of the surrounding rock mass, and the stress in the rock mass redistributes, resulting in displacement and deformation. When the stress of rock mass is greater than its yield strength, the rock mass will be destroyed. So, in order to prevent the blockage of cavities due to large-scale collapse and deformation to repair wells and destroy production casing and central tubing, It is necessary to understand the stress and strain distribution and failure range of rock mass around the cavity during the development of the cavity. The study of the stability of horizontal cavities surrounding rock is also of great significance to the size of the reserved pillars in the design of well distribution. In this paper, based on the geological conditions of the kazan natural alkali mine area, a simplified model is established by using FLAC3D software. In order to simulate the stress distribution and strain of the surrounding rock of different scale horizontal solution cavities, it is hoped that it can help the mining of Kazan natural alkali mine as much as it can.
【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD871
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本文编号：1583108