The rockbursts in the Upper Silesian Coal Basin in Poland

Coal mining realised in Upper Silesian Coal Basin is the main course of occurrence of bumps and rock-bumps. Geodynamical phenomena described as the rock-bumps occur in the area of GZW from the end of the 19th century. The mechanism of the rock-bumps phenomenon, due to the complexity, didn??t allow elaborating the completely effective method of its forecasting. However, increasing amount and the scale of rock-bumps, due to the development of mining, have extorted the scientific circles to perform works devoted to the elaborating newer and newer and better and better methods of the assessment of liability to rock-bumps, likewise methods of rock-bumps hazard assessment.     

Impact of mining on the groundwater chemistry in the Upper Silesian Coal Basin (Poland)

The Upper Silesian Coal Basin (USCB), 7500 sq.km area (including 5500 sq.km in Poland), is situated in the Variscian Upper Silesian intermountain depression. Coal-bearing Upper Carboniferous rocks occur beneath the permeable Mesozoic and Quarternary sediments in the NE part of the USCB and the impermeable Tertiary clay series in the southern and north—western parts. Studies on hydrogeochemical environment showed a normal vertical and horizontal hydrogeochemical zone in the full extent of the basin. This zone is characterized by changes in mineralization and chemical of waters along circulation routes. Strongly mineralized waters of isolated structures represent brines of the type Cl?Na and specially Cl?Na?Ca. A general trend of increased mineralization is noted along with depth of occurrence of water independently of age of the strata. The general regularity is disturbed by the phenomena of hydrochemical inversion mainly due to the mining activity. In the USCB coal deposits have began to be intensively exploited as early as the 18th century. The coal seams are exploited by the underground mining method, mainly by the longwall system, down to the average depth from 650 m to 1200 m. The steadily increasing mining depth and the opening of new mining levels increase the extent of drainage by mines and amounts as well as salinity of pumped out water. The total quantity of water pumped out of mines equals 724 m³/min. Area of decreased piezometric heads, because of the mine drainage, covers about 2000 sq.km. As the coal mine workings are carried out in different hydrochemical zones, the chemistry of the pumped mine waters vary significantly, with the mineralization of natural mine water ranging from 0.2 to 372.0 g/dm³. The artificial hydraulic interconnections created by mining activities and deep drainage cause changes in the natural hydrochemical regime of groundwater. The desalination effect caused by mining activity depends mainly on the depth and size of mining, duration of exploitation, drainage activity and geological conditions of the USCB. The present hydrochemical zone in the USCB determined by the mining impact is shown on the maps of groundwater mineralization at the depth of 500 and 750 m, as well as on the map of the depth of the occurrence of saline waters (35 g/dm³). There is a close correlation between mineralization of water in the Carboniferous within the coal fields and the type of overlying rocks as well as degree in which the rock mass is affected by mine workings. The maximum salinity of water was found in depressional structures under the cover of sealing. Tertiary rocks, host structure not covered by the Tertiary and affected by mine workings for over a hundred years are characterized by a marked desalination of waters to the depth of about 500 m.     

Main Key Heritage Adit (Sztolnia Dziedziczna) in Zabrze,Upper Silesian Coal Basin,Poland

Mine Water and the Environment - The Main Key Heritage Adit in Zabrze was used during from 1799 to 1953 to drain a series of underground coal mines and is the longest such facility in Europe. It...     

Water Hazard Assessment in Active Shafts in Upper Silesian Coal Basin Mines

Since 1976, there have been six inrushes of water into shaft mine workings in the Upper Silesian Coal Basin in Poland, with two of the more serious events occurring during the last 3 years. A safety assessment was conducted, considering inflow intensity, the amount of suspended material contained in the water flowing into the shaft, the proportion of water-bearing formations in the vertical profile, the condition of the shaft lining and safety pillar, and the history of the shaft. A risk assessment system is proposed to classify mine shafts with respect to the risk of a water hazard occurring, based on these factors. Each of the risk factors was assigned a weight, based on their relative significance, and then a method of evaluating each of these factors was developed. The proposed approach may be the basis for a more detailed, expert system for timely assessment of water hazard risk analysis. It may also be possible to adapt it to different geological and mining conditions.     

The probability of rockburst occurrence in the Upper Silesian Coal Basin area dependent on natural mining conditions

The presented assessment system of the rockburst occurrence probability and of the state of rockburst hazard takes into account the natural conditions of mining operations over the Upper Silesian Coal Basin area. The principal assessment factors governing the rockburst occurrence probability and the state of rockburst hazard, which have been included in the author’s system, are as follows: depth of coal seam, rock mass structure, geomechanical properties of rocks, energetic properties of rocks, coal seam thickness, distance between a coal seam and a potential seismogenic layer, maximum seismic energy of tremors from a given coal seam. The following four classes of rockburst hazard have been distinguished: no hazard, low hazard, moderate hazard, high hazard. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 6, pp. 55–62, November–December, 2006.     

Mechanical Properties of Carboniferous Rocks in the Upper Silesian Coal Basin under Uniaxial and Triaxial Compression Tests

Many years' studies of geological properties or rocks from the Upper Silesian Coal Basin have resulted in acquisition of a substantial data base of mechanical parameters or rocks over the total strain range. It is found that the post-peak rock properties are closely related with the peak strength and the pre-peak properties. The relationship between the uniaxial ultimate strength, elastic modulus, and drop modulus are determined. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 44–48, March–April, 2005.     

Using the DRASTIC System to Assess the Vulnerability of Ground Water to Pollution in Mined Areas of the Upper Silesian Coal Basin

Abstract  An attempt was made to use the U.S. EPA DRASTIC ranking system to assess the vulnerability of ground water in the Upper Silesian Coal Basin. Analysis of the various system components indicate that several DRASTIC factors would have to be modified to consider the effects of mining, subsidence, and ground water rebound.     

Selected ions and major and trace elements as contaminants in coal-waste dump water from the Lower and Upper Silesian Coal Basins (Poland)

Many temporary and permanent reservoirs of water occur on or near coal-waste dumps in the Lower-and Upper Silesian Coal Basins (Poland).Little or nothing is kno...     

永红煤矿峰峰组上部隔水性能研究

为了科学评价永红煤矿下组煤受奥灰水威胁的程度,分析研究峰峰组上部岩层的隔水性能,永红煤矿采用了水文地质钻探、抽水试验、压水试验、水化学特征分析等多种技术手段,对井田内峰峰组上部的隔水性能进行了分析和研究。得出了峰峰组上部35m以内具有一定的隔水性能,可视为相对隔水层。     

四川省煤矿区岩溶水赋存特征及防治措施

四川省煤矿区水文地质条件复杂,岩溶水对煤矿安全开采构成较大的威胁。在分析四川省含煤地层特征的基础上,系统研究了四川省煤矿区岩溶水分布特征和赋存形态,并通过分析经典案例得出岩溶突水的原因主要为自然原因和人为原因,提出了通过加强煤矿水文地质补勘、疏水降压开采、优化排水系统、选择合适采煤工艺、落实企业防治水主体责任等岩溶水综合防治措施。     

煤矿水质保障技术实践分析

针对目前煤矿用水存在的问题,结合现有技术及其煤矿井下的实际要求,通过矿井水的大颗粒及悬浮物自动反冲洗过滤技术、高硬度水的软化、再生技术、pH值自动控制技术及矿井用水水质保障配套工艺技术等方面开展实践研究,寻找出一套适用于煤矿防降尘及冷却设备的用水水质保障工艺技术及配套装备,有效治理矿井粉尘危害,减小矿工的尘肺发病率,降低采掘设备因其冷却失效而造成的损失。     

Mine Water for Energy and Water Supply in the Central Coal Basin of Asturias (Spain)

The Asturian Central Coal Basin (NW Spain) is generally characterized by moderately porous and permeable rocks, such as sandstone, limestone, and shale. Groundwater mostly flows through open fractures, voids, and decompression zones associated with coal mining. Exploitation of water resources in former coal mines could contribute to the economic well-being of communities affected by closure. The potential value of mine water associated with the flooded Barredo and Figaredo mine shafts near the town of Mieres was studied. This reservoir could supply water for 60,000 people; this could possibly be doubled by co-managing the river flow and underground resources. We studied the potential recovery of energy from the thermal value of this mine water (using water-to-water heat pumps). Two district heating systems are proposed: a low-temperature network (35 °C) for domestic heating and a very-low temperature network (20 °C) for large users, such as shopping centres, that need both heating and cooling. Return flow to the reservoir can generate electricity by means of micro-turbines. Preliminary estimates of profitability appear favourable, along with a sizable reduction in CO₂ emissions compared to natural gas heating. Extrapolation of these results to other mine water reservoirs in Central Asturias implies a potential of 40 million m³ per year for water supply, and an energy supply capacity close to 260,000 thermal MWh per year.     

Determining of safety pillars in the vicinity of water reservoirs in mine workings within abandoned mines in the Upper Silesian Coal Basin (USCB)

Against a background of hydrodynamic conditions connected with abandoning of significant number of mines and vast water reservoirs forming within them, basic methods of the assessment of strength of safety pillars used in coal mines in the USCB are presented. In the light of geomechanical research and conditions in mines in the USCB, the paper indicates a possibility of verification of safety pillar dimensions. On the example of one of mines in the USCB conditions for safety pillars stability in complicated mining conditions are assessed. The author also proposes a methodology of attempt and safety zones indication for existing safety pillars which would simultaneously be safety zones for designed exploitation.     

Spatial Distribution Characteristics of Coal Mine Drainage Water Quality in China

Mine Water and the Environment - Coal mine drainage (CMD) reuse is an important method for optimizing water resource supply in arid/semi-arid regions. This study analyzed the spatial distribution...     

影响邹庄煤矿7_2煤层瓦斯赋存的因素

邹庄煤矿为宿县矿区新建矿井,32煤层为即将开采煤层,72煤层为下一开采煤层。72煤层受岩浆岩侵蚀严重,且埋深较32煤层深,因此72煤层的瓦斯赋存情况更加复杂。文章系统分析影响瓦斯赋存的因素,采用灰色关联方法,对影响72煤层瓦斯含量的各个因素进行研究,建立了灰色关联模型,并计算出了各项因素的关联度。研究结果表明:影响邹庄煤矿72煤层瓦斯赋存的主要因素为煤的灰分、煤层埋藏深度、地层厚度、挥发分、煤厚与地层厚度比等,利用多元回归的分析方法对邹庄煤矿72煤层的瓦斯含量进行预测,并为其以后的安全开采提供前瞻性预测数据。     

汪家寨煤矿煤中汞的含量分布与赋存状态

采用原子荧光光度计测定了汪家寨煤矿煤中的汞含量,通过筛分、浮沉实验研究了煤中汞的分布,采用逐级化学提取研究了煤中汞的赋存状态。结果表明:汪家寨煤矿煤中的汞含量为0.41μg/g,属于高汞煤,煤中的汞具有很高的无机亲和性和亲硫性,汞含量基本上随着灰分和硫分的增大而增大。煤中汞的赋存主要以残渣态和有机质及硫化物结合态为主,不同赋存状态汞含量依次为残渣态>有机质及硫化物结合态>可交换态>氧化物结合态>碳酸盐结合态。     

双柳煤矿开采上组煤层太灰水突水危险性评价

双柳煤矿4号煤层存在底板太灰水带压开采问题,文中在概述井田内太灰水贮存特征的基础上,分别利用突水系数法和多层叠加抗压强度比值系数法进行了太灰水对4号煤层突水危险性评价,最后叠置二者评价结果做出了综合评价.以期为煤矿防治水工作提供参考依据.     

龙门煤矿矿井涌水水源判别分析

随着矿井开采深度的增加,矿井水害已成为龙门煤矿安全生产的主要隐患。每个煤矿有一个或多个含水层,各含水层的水质成分是已知的,且各含水层之间的水质存在一定的差异,具有明显的分类性。结合洛阳龙门煤业有限公司龙门煤矿矿井涌水各含水层水源的成分,用聚类分析和元素守恒定律方法对龙门矿井正常涌水水源构成进行了定量分析,从中寻找出一种新的方法和途径。     

怡泽煤矿煤与瓦斯突出异常现象浅析

根据怡泽煤矿突出煤层储存状况、构造分布、瓦斯及其压力特征分析,研究该矿煤与瓦斯突出的发生机理,为防治煤与瓦斯突出灾害提供科学依据。     

大柳塔煤矿的安全质量标准化

介绍了大柳塔煤矿的质量标准化的进展情况并介绍了矿井质量标准化的基本知识，最后提出了提高质量标准化的措施，对矿井顺利的进行质量标准化管理有一定的借鉴意义。