Application of analytical hierarchy process to selection of primary crusher

Selection of crusher required a great deal of design based on the mining plan and operation input. Selection of the best primary crusher from all of available primary crushers is a Multi-Criterion Decision Making (MCDM) problem. In this paper, the Analytical Hierarchy Process (AHP) method was used to selection of the best primary crusher for Golegohar Iron Mine in Iran. For this reason, gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impactor, hammer mill and feeder breaker crushers were considered as alternatives and capacity, feed size, product size, rock compressive strength, abrasion index and mobility of crusher were considered as criteria. As a result of our study, the gyratory crusher was offered as the best primary crusher for the studied mine.     

Fuzzy TOPSIS method to primary crusher selection for Golegohar Iron Mine（Iran）

Selection of the crusher required a great deal of design regarding to the mine planning. Selection of suitable primary crusher from all of available primary crushers is a multi-criterion decision making（MCDM） problem. The present work explores the use of technique for order performance by similarity to ideal solution（TOPSIS） with fuzzy set theory to select best primary crusher for Golegohar Iron Mine in Iran. Gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impact crusher, hammer mill and feeder breaker crushers have been considered as alternatives. Also, the capacity, feed size, product size, rock compressive strength, abrasion index and application of primary crusher for mobile plants were considered as criteria for solution of this MCDM problem. To determine the order of the alternatives, closeness coefficient is defined by calculating the distances to the fuzzy positive ideal solution（FPIS） and fuzzy negative ideal solution（FNIS）. Results of our work based on fuzzy TOPSIS method show that the gyratory is the best primary crusher for the studied mine.     

矿山皮带运输机远程控制与监视系统的设计及应用

数字矿山是当今采矿科学、信息科学、人工智能、计算机技术和3S技术发展与高度结合的产物,它将深刻改变传统的采矿生产活动和人们的生活方式。本文针对矿山井下运输及工业电视监视系统的技术要求,同时考虑其先进性、安全性、可靠性以及安装、使用和维护的方便性而设计了矿山皮带远程控制系统。     

灵新煤矿地下水库煤柱坝体合理尺寸研究

近年来,煤矿地下水库技术已成为西部地区保护和利用矿区水资源的重要手段,地下水库矿井水已成为西部地表生态灌溉的重要水源之一。以西部矿区灵新煤矿近距离倾斜煤层群采掘地质条件为工程背景,针对该矿首座煤矿地下水库建设过程中遇到的煤柱坝体留设问题,采用数值模拟的方法,分析了六采区工作面开采和水库储水压力两大因素对煤矿地下水库煤柱坝体的影响。研究表明:相关工作面回采后,会在煤柱坝体及邻近围岩中产生塑性区,随着煤柱坝体宽度的增加,煤柱坝体及附近围岩中塑性区相互贯通的趋势逐渐减弱。当煤柱坝体宽度增至50 m时,塑性区相互贯通的现象消失;当煤柱坝体宽度增加到60 m时,煤柱坝体及邻近围岩中的塑性区间距(塑性区未贯通区域)扩大至40 m左右。在储水压力作用下,煤柱坝体及邻近围岩中的塑性区裂隙将发生二次扩展,随着水压的增大,裂隙扩展长度逐步增大,在3 MPa水压(储水高度300 m)作用下塑性区裂隙扩展长度达到5 m左右。因此,为防止水力作用下煤矿地下水库透水灾害的发生,认为煤柱坝体合理尺寸应取60 m。     

Partition airflow varying features of chaos-theory-based coalmine ventilation system and related safety forecasting and forewarning system

To realize real-time monitoring and short-term forecasting and forewarning of coalmine ventilation systems(CVS), in this paper, we first established a joint surface and underground CVS safety management system consisting of main ventilation fan, safety-partition linked passageways, and air-required locations. We then applied chaos theory to identify the air quantity and gas concentration of underground partition boundaries, and adopted a fixed data quantity, multi-step progressive, weighted first-order local-domain method to setup a chaos prediction model and a CVS safety forecasting and forewarning system formed by the normal change level, orange forewarning level, and red alarm level. We next conduct the on-field application of the system in a coalmine in Jining, Shandong, China. The results showed that (1) in the statistical scale of 5 min, the changes in both air quantity and gas concentration along CVS partition airflow boundaries were characteristic of chaos and could be used for short-term chaos prediction, and the latter was more chaotic than the former;(2) the setup chaos prediction model had a higher prediction precision and the established safety prediction system could not only predict the variation in CVS stability but also reflect the rationality of underground mining intensity. Thus, this CVS safety forecasting and forewarning system is of better application value.     

准大采高综放工作面矿压特征的研究

本文以同煤集团云冈矿8212工作面地质条件为背景,对工作面矿压规律进行实测分析研究,结果表明:1)工作面支架平均工作阻力为2 016.1 k N,占其额定工作阻力(7 000 k N)的28.8%,该工作面支架的额定工作阻力可以满足顶板的管理要求。支架前后柱工作阻力分布较平均,能正常工作。2)工作面支架平均循环末阻力为3 147.0 k N,占其额定工作阻力(7 000 k N)的45.0%,该工作面平均循环末阻力主要分布区间为2 800~3 800 k N,即工作面支架的额定工作阻力完全可以支撑顶板。3)工作面超前支承压力作用范围在35~38 m处,随工作面的逐步推进,其增幅也逐步增加。该结论可为类似条件下其他工作面开采过程中矿压显现规律的研究提供参考。     

Changes in the extent of surface mining and reclamation in the Central Appalachians detected using a 1976-2006 Landsat time series

Surface mining and reclamation is the dominant driver of land cover land use change (LCLUC) in the Central Appalachian Mountain region of the Eastern U.S. Accurate quantification of the extent of mining activities is important for assessing how this LCLUC affects ecosystem services such as aesthetics, biodiversity, and mitigation of flooding. We used Landsat imagery from 1976, 1987, 1999 and 2006 to map the extent of surface mines and mine reclamation for eight large watersheds in the Central Appalachian region of West Virginia, Maryland and Pennsylvania. We employed standard image processing techniques in conjunction with a temporal decision tree and GIS maps of mine permits and wetlands to map active and reclaimed mines and track changes through time. For the entire study area, active surface mine extent was highest in 1976, prior to implementation of the Surface Mine Control and Reclamation Act in 1977, with 1.76% of the study area in active mines, declining to 0.44% in 2006. The most extensively mined watershed, Georges Creek in Maryland, was 5.45% active mines in 1976, declining to 1.83% in 2006. For the entire study area, the area of reclaimed mines increased from 1.35% to 4.99% from 1976 to 2006, and from 4.71% to 15.42% in Georges Creek. Land cover conversion to mines and then reclaimed mines after 1976 was almost exclusively from forest. Accuracy levels for mined and reclaimed cover was above 85% for all time periods, and was generally above 80% for mapping active and reclaimed mines separately, especially for the later time periods in which good accuracy assessment data were available. Among other implications, the mapped patterns of LCLUC are likely to significantly affect watershed hydrology, as mined and reclaimed areas have lower infiltration capacity and thus more rapid runoff than unmined forest watersheds, leading to greater potential for extreme flooding during heavy rainfall events.     

Analytical Framework for a Risk-based Estimation of Climate Change Effects on Mine Site Runoff Water Quality

A conceptual analytical framework was developed for the risk-based estimation of climate change effects on mine waste runoff water quality. The modeling approach incorporates temporal variability in both precipitation and temperature using trend analyses from historical datasets and the resulting effects on water balances and geochemical weathering rates. A case-study method was used to develop and present the model for regions near the city of Yellowknife, Northwest Territories, Canada. Time-resolved relative precipitation and weathering factors can be calculated using climate data and site-specific estimates regarding mine waste properties. Interpretation of these factors allows an assessment of when the period of highest analyte concentrations are expected to occur under a given risk scenario over a modeling timeframe, whether low precipitation or warming effects are more important in determining water quality issues, and the relative magnitudes of water quality under differing risk scenarios. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

我国铀矿冶设施退役治理现状及对策

铀矿冶设施退役治理是一项政策性强、公众敏感、环境要求高、治理周期长、涉及面广、耗资大的环境安全系统工程。本文根据国外的经验和我国多年的退役治理工作的实践,对铀矿冶退役治理工作的目标、技术政策、治理原则和治理技术等问题进行了分析、讨论,并提出相关建议。     

Experimental simulation of spiral slip lines on granular materials

The experimental results of modeling geomedium around a mine working are reported. Two families of spiral slip lines are reproduced on a granular material. One or two families of log spiral slip lines arise around a cylindrical foreign body simulating a supported mine working. It is shown that shears on the lines of different families develop irregularly. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 3–9, March–April, 2009.