土耳其卡赞碱矿对接井水溶开采技术创新综述

土耳其卡赞碱矿钻井项目主要利用高精度中靶技术使定向水平井与垂直井在碱层中对接后进行水溶开采的方法。该项目通过长期大量的钻井工作,在已有的钻井技术与地质条件基础上,改进完善了与地层相适应的钻井技术,建立了矿区三维地质模型,设计应用了水平分支对接井,优化了钻井轨迹设计,建立起非矿层与矿层的基准物探测井响应曲线,探索出矿区地层致斜机理及相应钻井防斜措施,研究并应用了各种井底钻具组合与设备,采用了提高水平钻井轨迹控制精度的技术方法。上述多种水溶采矿钻井技术创新措施的应用,提高了矿山规划能力、降低了施工成本、提高了资源回采率、缩短了施工工期、降低了劳动强度、提高了钻进效率、减少了施工用地以及对环境的破坏。可为天然碱矿及可溶性矿产的整体矿山规划,以及钻井水溶采矿技术的提高提供借鉴。     

基于灰色模糊模型的塔山煤矿构造复杂程度定量评价

为实现大同煤田塔山煤矿构造复杂程度的定性-定量综合分析和分区评价,本次研究充分收集研究区钻孔实测数据和井田详查和勘探阶段的区调资料,以及各煤层采掘工程平面图,统计了研究区近百条褶皱和断裂构造产状、落差和延伸长度等参数,绘制了研究区构造纲要图.厘定了断层密度、断层强度、断层影响指数和褶皱的平面变形系数4个构造评价指标,应...     

甘肃省宁正矿区新庄井田煤质及工业用途评价

甘肃省宁正矿区新庄井田位于宁县县城南约15 km处,矿区面积208 km²,属于大型井田,煤炭资源量达19. 25亿t。从煤的物理性质、煤岩性质、煤的化学性质和工艺性能等方面分析,认为矿区的煤具有中高挥发分、低灰、低硫—中硫、低磷、高发热量、弱粘结,高热稳定性、较低软化温度灰、较难磨、易选—中等可选的特点,煤类主要为不粘煤,其次为弱粘煤,少量中强粘结煤,原煤或浮选后的浮煤可作为动力用煤、气化用煤等。     

笏山矿难应急救援钻孔施工技术

2021年笏山矿难钻孔救援是我国钻孔救援成功的典型案例。由于地层坚硬且裂隙发育,导致钻孔易偏斜且易发生卡钻事故,针对这一特殊情况采用潜孔锤空气泡沫钻进及螺杆马达纠偏等钻进工艺,成功完成了小口径生命保障孔钻探救援任务,同时本文也对生命保障孔、排水孔和大口径救生孔钻探救援技术进行了总结,对今后开展钻孔救援工作提出有待改进的问题和建议。     

Management of karst water resources in mining area: dewatering in mines and demand for water supply in the Dongshan Mine of Taiyuan, Shanxi Province, North China

Coalfields in North China contain six to seven coal seams in the Permo-Carboniferous strata. The coal seams are underlain by the Ordovician limestone. Large-scale dewatering or depressurizing of the karst aquifer was considered essential to avoid water inrushes and keep the mines safely operational. This practice, however, has caused water supply shortage in the mining areas. The most effective solution to this conflict is to use the uncontaminated karst water from the mines for water supply. This paper explores a management model to maximize the utilization of the karst water while maintaining the safe operation of the mines. The model can provide essential information on water resource distribution for decision makers. The model was applied to the Dongshan Coal Mine in Taiyuan City, China.     

Simulation of Paleotectonic Stress Fields and Distribution Prediction of Tectonic Fractures at the Hudi Coal Mine, Qinshui Basin

Study on tectonic fractures based on the inversion of tectonic stress fields is an effective method. In this study, a geological model was set up based on geological data from the Hudi Coal Mine, Qinshui Basin, a mechanical model was established under the condition of rock mechanics and geostress, and the finite element method was used to simulate the paleotectonic stress field. Based on the Griffith and Mohr-Coulomb criterion, the distribution of tectonic fractures in the Shanxi Formation during the Indosinian, Yanshanian, and Himalayan period can be predicted with the index of comprehensive rupture rate. The results show that the acting force of the Pacific Plate and the India Plate to the North China Plate formed the direction of principal stress is N-S, NW-SE, and NE-SW, respectively, in different periods in the study area. Changes in the direction and strength of the acting force led to the regional gradients of tectonic stress magnitude, which resulted in an asymmetrical distribution state of the stress conditions in different periods. It is suggested that the low-stress areas are mainly located in the fault zones and extend along the direction of the fault zones. Furthermore, the high-stress areas are located in the junction of fold belts and the binding site of multiple folds. The development of tectonic fractures was affected by the distribution of stress intensity and the tectonic position of folds and faults, which resulted in some developed areas with level Ⅰ and Ⅱ. There are obvious differences in the development of tectonic fractures in the fold and fault zones and the anticline and syncline structure at the same fold zones. The tectonic fractures of the Shanxi Formation during the Himalayan period are more developed than those during the Indosinian and Yanshanian period due to the superposition of the late tectonic movement to the early tectonic movement and the differences in the magnitude and direction of stress intensity.     

Use of sample color to estimate oxidized Fe content in mine waste rock

 Color, a readily perceived feature of natural earth materials, including mine waste, often represents compositional variation as a result of oxidative processes involving Fe. Near surface samples from excavated trenches in a mine-waste rock pile were collected to investigate the relationship between color and contents of Fe, Cu, and S. The silt+clay fraction (<0.05 mm) was isolated from recognizable colored material of the bulk sample for determination of pH, total and extractable Fe and Cu, and bulk mineralogy. Rock fragments within the pile exhibited coatings of crystalline gypsum and amorphous Fe. These coatings result from weathering (secondary products) and play important roles in surface reactions of waste rock piles, such as adsorption of anions (SO₄ ^2–) or coprecipitation of Fe with Cu. The correlation between color (Hurst method) and extractable Fe was high. Although color is influenced by site conditions such as original mineral composition, materials handling, weathering conditions etc., the results suggest that color measurements may provide an inexpensive and rapid estimation for secondary iron compounds and associated sorbed elements. Received: 5 April 1998 · Accepted: 30 June 1998     

Arsenic distribution during formation and capping of an oxidised sulphidic minesoil, Macraes mine, New Zealand

A minesoil has developed over 5 years oxidative exposure on sulphide concentrate tailings (ca. 1 wt.% As) at the Macraes mesothermal gold mine, New Zealand. The minesoil has a dry crust which has formed due to evaporative drying. This dry crust is enriched in arsenic (ca. 5 wt.% As) as scorodite (FeAsO₄·2H₂O) because of upward mobility of dissolved arsenic during drying. Similar enrichment of arsenic has occurred along the walls of desiccation cracks which extend over 1 m into the minesoil. Capping of the tailings and minesoil with wet tailings (pH=8) results in dissolution of scorodite and remobilization of arsenic on the millimetre scale. Experimental capping of the minesoil with wet calcium carbonate remobilized some arsenic from scorodite on the centimetre scale, but much original arsenic enrichment was preserved after 400 days. A layer of gypsum (CaSO₄·2H₂O) and iron oxyhydroxide cementation developed at the interface between the minesoil and the experimental calcium carbonate cap, restricting water flow. This layer was ca. 1 mm thick after 400 days. Theoretical comparison between advection and diffusion in the minesoil suggests that diffusion is an important mechanism for chemical mobility on the 1–50-year time scale. However, advection can be important in secondary porosity of the dry crust of the minesoil and water penetrates this zone at a rate of 1.5 mm/day.     

Mobilization and attenuation of heavy metals within a nickel mine tailings impoundment near Sudbury, Ontario, Canada

 The oxidation and the subsequent dissolution of sulfide minerals within the Copper Cliff tailings area have led to the release of heavy metals such as Fe, Ni, and Co to the tailings pore water. Dissolved concentrations in excess of 10 g/l Fe and 2.2 g/l Ni have been detected within the shallow pore water of the tailings, with increasing depth these concentrations decrease to or near analytical detection limits. Geochemical modelling of the pore-water chemistry suggests that pH-buffering reactions are occurring within the shallow oxidized zones, and that secondary phases are precipitating at or near the underlying hardpan and transition zones. Mineralogical study of the tailings confirmed the presence of goethite, jarosite, gypsum, native sulfur, and a vermiculite-type clay mineral. Goethite, jarosite, and native sulfur form alteration rims and pseudo-morphs of the sulfide minerals. Interstitial cements, composed of goethite, jarosite, and gypsum, locally bind the tailings particles, forming hardpan layers. Microprobe analyses of the goethite indicate that it contains up to 0.6 weight % Ni, suggesting that the goethite is a repository for Ni. Other sinks detected for heavy metals include jarosite and a vemiculite-type clay mineral which locally contains up to 1.6 weight % Ni. To estimate the mass and distribution of heavy metals associated with the secondary phases within the shallow tailings, a series of chemical extractions was completed. The experimental design permitted four fractions of the tailings to be evaluated independently. These four fractions consisted of a water-soluble, an acid-leachable, and a reducible fraction, as well as the whole-rock total. Twenty-five percent of the total mass of heavy metals was removed in the acid-leaching experiments, and 100% of the same components were removed in the reduction experiments. The data suggest that precipitation/coprecipitation reactions are providing an effective sink for most of the heavy metals released by sulfide mineral oxidation. In light of these results, potential decommissioning strategies should be evaluated with the recognition that changing the geochemical conditions may alter the stability of the secondary phases within the shallow tailings. Received: 9 April 1997 · Accepted: 21 July 1997     

矿井突水水源的Bayes逐步判别分析研究

对Bayes逐步判别法在矿井突水水源判别中的应用进行研究分析。选用六大常规离子（ Ca2＋、Mg2＋、K＋＋Na＋、SO42-、Cl-、HCO3-）作为判别因子,建立Bayes逐步判别分析模型,以内蒙唐家汇矿区突水水源判别为例,在建立的判别模型回判检验准确率仅60%,分析原因可能与选定的特征判别因子对该矿区水样分类影响能力较弱有关。增加总硬度、碱度、PH值和矿化度作为判别因子,重新建立Bayes判别分析模型,使回判准确率提高至90%,证明适当增加特征判别因子对改善Bayes逐步判别模型的可靠性和稳定性有利。经对唐家会矿区的3个未知样本进行了判别分析,并与距离判别法和模糊综合评判法判别结果对比,结果表明Bayes逐步判别模型准确性较好,判别准确率与距离判别结果完全相同,而优于模糊综合评判方法。在合理选取特征判别因子的情况下,Bayes逐步判别法是目前矿井突水水源判别的有效方法。