A Hydro-Economic Model for Optimizing Management of Mine Water: A Case Study in the Suancigou Coal Mine,Northwestern China

Mine Water and the Environment - Comprehensive analysis of hydrogeological conditions at a typical coal mine in northwestern China allowed us to establish a groundwater numerical model, which we...     

Risk Evaluation of Bed-Separation Water Inrush: A Case Study in the Yangliu Coal Mine,China

Water that accumulates in the void space where overburden strata separate can be an inrush source. We established an engineering geology model of bed-separation water inrush, and chose five factors (hard rock thickness, coal seam thickness, aquifuge thickness, aquifer thickness and hydrostatic head) as risk factors. Additionally, based on an analysis of hydrogeological and engineering geological conditions at two areas in the Yangliu coal mine, the comprehensive weight values of these factors were found to be 0.32, 0.24, 0.18, 0.15, and 0.11, respectively, using fuzzy analytic hierarchy process and entropy method. Finally, the data were normalized, and a zoning map for risk evaluation was created using the space superposition function of GIS. This method was further used to evaluate the risk at the Haizi coal mine, and the results were in accordance with an inrush disaster that occurred at the 745 working face at that mine. This validated the model’s practical applications. This provides mines with strategies to prevent and control bed-separation water inrush.     

Application of the Analytic Hierarchy Process to Assessment of Water Inrush: A Case Study for the No. 17 Coal Seam in the Sanhejian Coal Mine, China

Disasters caused by water inrush affect many coal mines in China. In order to predict and prevent water inrushes during mining of the no. 17 coal seam in the Sanhejian coal mine, the factors that affect water inrush from the underlying Ordovician limestone were studied using the analytic hierarchy process (AHP). The AHP method is based on the geographic information system, through which the sub-thematic layer and the overlying layers of each dominating factor were constructed. An expert system was used to calculate weighting for each factor. Integration of the controlling factors through the AHP allowed us to develop a vulnerability index map in which the mining area was divided into different zones according to the risk level for water inrush during mining. Furthermore, water control measures were recommended in response to each risk level.     

Hydrogeochemistry and Contamination of Trace Elements in Cu-Porphyry Mine Tailings: A Case Study from the Sarcheshmeh Mine,SE Iran

Geochemical and hydrochemical investigations were performed to understand the contamination potential of the Sarcheshmeh mine tailings. The geochemical mobility for the tailings is as follows: Cu > Cd > Co > Zn > Ni > Mn > S > Cr > Sn > As > Se > Fe = Bi > Sb = Pb = Mo. Highly mobile and contaminant elements (Cd, Cu, Zn, Mn, Co, Ni, S, and Cr), which significantly correlated with each other, were mainly concentrated in the surface evaporative layer of the old, weathered tailings, due to the high evaporation rate, which causes subsurface water to migrate upward via capillary action. The contamination potential associated with the tailings is controlled by: (1) dissolution of secondary evaporative soluble phases, especially after rainfall on the old weathered tailings, accompanied by low pH and high contamination loads of Al, Cd, Co, Mg, Cr, Cu, Mn, Ni, S, Se, and Zn; (2) processing of the Cu-porphyry ore under alkaline conditions, which is responsible for the high Mo (mean of 2.55 mg/L) and very low values of other contaminants in fresh tailings in the decantation pond; (3) low mobility of As, Fe, Pb, Sb, Mo, and Sn due to natural adsorption and co-precipitation in the tailings oxidizing zone. Speciation modeling showed that sulfate complexes (MSO₄ ⁺, M(SO₄)_(aq), M(SO₄) ₂ ^?2 , and M(SO₄) ₂ ^? ) and free metal species (M⁺² and M⁺³) are the dominant forms of dissolved cations in the acidic waters associated with the weathered tailings. In the alkaline and highly alkaline waters, trace element speciation was controlled by various hydroxide complexes, such as M(OH)⁺, M(OH) ₃ ^? , M₃(OH) ₄ ⁺² , M₂(OH) ₃ ⁺ , M(OH)_2(aq), M(OH) ₄ ^?2 , Me(OH) ₂ ⁺ , Me(OH) ₄ ^? , Me(OH) ₂ ⁺ , Me(OH)_3(aq), and Me(OH) ₄ ^? (where M represents bivalent and Me represents trivalent cations). The speciation pattern of As, Mo, and Se is mainly dominated by oxy-anion forms. The obtained results can be used as a basis for environmental management of the Cu-porphyry mine tailings.     

Assessment of Metal Contamination in the Mine Water of the West Bokaro Coalfield,India

This study was carried out in the West Bokaro coalfield area of the Jharkhand state of India to assess water quality for drinking and domestic purposes. Thirty mine water samples were collected from opencast and underground mines, and concentrations of Al, As, Ba, Cr, Cu, Fe, Mn, Ni, Se, and Zn were determined using ICP-MS. Spatial distribution maps were prepared using GIS software so that the quality of the mine water could be easily understood. Metal concentrations were higher in the pre-monsoon season than in the post-monsoon season, irrespective of location, but there were more significant seasonal variations in the opencast mine water than in the underground mine water. The concentrations of Al, Ba, Fe, Mn, and Ni exceeded the desirable as well as the permissible drinking water limits in both seasons. The quality of the surface water as well as the groundwater in the region may be adversely affected by the high metal concentrations in this mine water.     

开滦林南仓矿井水处理研究

煤炭是我国当前及未来很长一段时间的工业资源,随着工业的发展对煤炭需求的不断增加,我国煤炭的开采量也逐年增加,随之而来的是对地下水资源破坏日趋严重。文章就开滦林南仓矿井水如何处理、利用做了一些有益的尝试。     

煤层底板突水危险性分析：以唐山市钱家营矿12煤层底板为例

唐山市钱家营矿地处开平向斜南东翼,地质条件复杂,为探究钱家营矿12煤层底板突水危险性,基于矿井钻孔与水文地质资料,选取钱家营矿12煤层底板受奥灰水水压、隔水层厚度、有效脆性岩层厚度以及断层与褶皱分布作为影响钱家营矿12煤层底板突水的主控地质因素,运用层次分析法对各主控因素进行评价、构造判断矩阵、计算各主控因素所占权重、引入危险性评价模型并为所得数据选取合理的界限值,最终得到钱家营矿12煤层底板突水危险性评价分区图。研究表明:钱家营矿12煤层底板突水可能性较大,尤其是构造较为发育的东北地区,对比矿井水文地质资料,评价结果与实际拟合较好。本次研究为有效防治煤层底板水害提供了理论与技术支持。     

Evaluation of Water Inrush Vulnerability and Feasibility Analysis of Mining Under Rivers: A Case Study Involving the Jinjie Coal Mine in China

Mine Water and the Environment - The shallow groundwater of the Quaternary Salawusu Formation in China is distributed widely in the arid and semi-arid areas of northern Shaanxi and is an essential...     

煤炭工业矿区规划与环境影响评价的探讨

改革开放以来,生态矿区开始成为世界矿区发展领域的主要建设模式,纵观目前的国内外矿区建设可以发现,煤炭工业生态矿区建设已成为了主流。文章探讨了煤炭工业矿区规划环境评价的必要性,论述了当前煤炭工业矿区规划环境评价存在的问题,从而建立了煤炭工业矿区规划环境评价体系,提出了相关的优化对策:合理规划矿区土地利用、推动环境容量的充分利用和构建人与人的和谐。     

Modeling Irrigation with Gypsiferous Mine Water: A Case Study in Botswana

The possible use of mine effluent for irrigation of agricultural crops was investigated for BCL Ltd. nickel mine (Selebi Phikwe, Botswana). The aims were to estimate the long-term water and salt balance under irrigation with gypsiferous mine water, as well as to make recommendations on cropping and management options. A simple but mechanistic edynamic soil water-salt balance generic crop growth model (SWB, Soil Water Balance) and a weather data generator (CLIMGEN) were used for long-term predictions. Eleven years of irrigation with BCL effluent were simulated for different cropping systems and irrigation management practices, followed by 39 years of irrigation with freshwater or dry land cropping. The long-term simulations indicated that between 661 and 2017 mm of mine effluent could be used annually through irrigation, depending on crop choice and irrigation management. Between 18% and 32% ot the total amount of salt added through irrigation was predicted to leach in 11 years, the remainder being precipitated in the 1.1 m deep soil profile in the form of gypsum. The rate of gypsum dissolution and leaching after 11 years of irrigation with mine water depended on management. Simulated root density-weighted electrical conductivities at saturation indicated favorable conditions for growth of summer crops, but a leaching fraction is recommended in winter. A lucerne perennial pasture was the most suitable cropping system from the point of view of mine water utilization and salt precipitation in the soil profile. Deficit irrigation (room for rain) followed by dry land cropping was the most suitable management strategy in order to limit salt leaching and possible ground water contamination. The acceptability of the proposed strategies will depend on Botswana's standards for environmental protection, as well as social and economic issues.     

城郊煤矿二水平煤层底板突水危险性综合评价研究

为了探究城郊煤矿深部延伸二水平主采二2煤层底板突水危险性,根据矿区二水平底板地层及断层构造特征,采用突水系数法和分形分维方法对二水平底板的断层构造复杂程度及突水危险性分别进行了量化分区与综合分区评价.结果表明,虽然两种方法的计算过程和量化分区参数不同,但所进行的量化分区具有较好的一致性,断裂构造复杂程度分维值与突水系数...     

济宁二号煤矿矿井水、生活污水复用工程

简要介绍济宁二号煤矿矿井水、生活污水的水质现状及处理工艺，着重说明复用工程的工艺流程及实施情况，并有针对性讨论了复用后所带来的经济效益。     

Mercury Contamination in Water and Sediments and the Associated Health Risk: A Case Study of Artisanal Gold-mining

Mine Water and the Environment - This study investigated mercury (Hg) contamination in the Gilgit-Baltistan, Pakistan. Water and sediment samples were collected from various sites...     

Optimal Scheduling of a Mine Water Drainage System Based on Improved Particle Swarm Optimization Algorithm: A Case Study of the Guhanshan Coal Mine,China

A groundwater drainage system comprising five drainage points and seven submersible pumps was designed to relieve the threat of flooding by 2.9 million m³ of mine water and a dynamic water supply volume of 718 m³/h in the Guhanshan Coal Mine. The key aim of the design was to ensure safe production. A mathematical model of the optimal scheduling of the water drainage system was constructed and solved using an improved particle swarm optimization algorithm to minimize long-term energy consumption. The algorithm had high convergence accuracy, and quickly and efficiently realized the optimal configuration of the pumping volume of the mine drainage system. When the Wucun mine was full of water, the flow of submersible pumps no. 1 (or 2) and nos. 3, 4, 5, and 6 were set to 58, 150, 150, 180, and 180 m³/h, respectively, and the energy consumption of the system was minimal. When the water level in the Wucun mine was less than ? 40 m, the lowest energy consumption was found when the flow rates of pumps nos. 3, 4, 5, 6, and 7 were, respectively set to 150, 150, 180, 180, and 58 m³/h. This overcame the shortcomings of adjusting the submersible pump flow based only on past experience and should be useful for many future mine water drainage projects.

     

汾源煤业5#煤层顶板含水层富水性及突水危险性评价

为评价5^#煤层顶板石灰岩含水层突水危险性,通过石灰岩含水层富水性的分析结果,确定石灰岩含水层富水性相对较强区域主要分布在井田的北部和中部;通过将冒裂程度与富水性分区叠加,得出石灰岩含水层突水危险性程度。结果表明:石灰岩含水层整体突水危险性弱,仅在井田东南部存在小部分突水危险区,井田范围内大部分区域均为较安全区和过渡区。     

Geothermal Water at a Coal Mine: From Risk to Resource

Geothermal water from a Cambrian limestone aquifer presented a flooding risk at the No. 8 coal 2₁ mine near Pingdingshan City, China. The water-bearing zones were identified using the mine transient electromagnetic method and direct current prospecting, and a groundwater drainage system was installed. After water drainage was implemented, the water level in the limestone near the haulway dropped 17.2 m in 277 days, greatly reducing the risk of a mine water inrush. The water quality, quantity, and temperature allowed it to be used for mineral baths, resulting in energy savings and emission reductions.     

Assessment and Prevention of Water and Sand Inrush Associated with Coal Mining Under a Water-filled Buried Gully: A Case Study

Mining under a water-filled buried gully risks a potentially serious water and sand inrush, especially if the bedrock is thin. A case study was conducted at a Chinese coal mine, where the thin overlying overburden was covered by widely distributed gullies. Several empirical formulas and numerical modelling indicated that the overlying strata was almost totally fractured and that all of the conditions for an inrush were met. Pre-mining dewatering and grout injection were initiated. The groundwater table was lowered by 13 surface pumping wells and 33 underground upholes that were drilled around the gully. Those located at the bottom of the gully were generally better in aquifer dewatering than those located at the banks. A barrier was constructed to avoid a water inrush by injecting a chemical grout into the bottom of the buried gully through 25 surface holes. Field observations of the water table, underground water yield, and overburden movement prove the validity of the assessment methods and treatments.     

Holistic Design of Wetlands for Mine Water Treatment and Biodiversity: A Case Study

Passive treatment wetlands are conventionally designed with the primary objective of purifying contaminated mine water; any benefit of enhanced biodiversity is ancillary. We propose a new approach that incorporates enhanced biodiversity as an explicit objective. In this approach, treatment units are selected based on water flows and chemistry and the ecological requirements of key species are identified. Elements of the wetland design that meet these distinct requirements are selected and sized, then merged within the constraints imposed by site geomorphology and hydrology. This concept is illustrated with the wetland design for the Los Bronces Mine in Chile, where aspects of treatment, biodiversity, and water management were developed separately, and then integrated into a holistic design. The treatment wetlands are integrated within the local ecology. This approach adheres more closely to the objective of designing wetlands that offer ecosystem services and also meets the requirements for long-term water treatment.

     

Catastrophic Evolution of Water Inrush from A Water-Rich Fault in Front of Roadway Development: A Case Study of The Hongcai Coal Mine

Mine Water and the Environment - A fault can be both the inrush channel and the water source. In order to better understand how such a mine disaster develops, a fluid–solid coupling analysis...     

煤矿火灾事故评价方法研究

目前用于矿井火灾评价的方法仅限于检查表法,依据专家给定分值确定矿井火灾危险程度,其评价结果带有很强的主观性,评价指标体系也不完善。通过对近两年35起典型火灾事故的统计分析,总结了诱发矿井火灾的7个主要因素:煤层自燃等级、井下工人素质、矿井通风管理、消防洒水系统、安全管理、矿井可燃物和机电设备失爆率。依据层次分析法确定各因素的权重,然后经过数据处理评定矿井火灾安全等级,并根据结果对矿井火灾事故防治提出合理的对策和建议。