基于时空属性的黄陵矿区瓦斯精准化预抽实践

为了实现黄陵矿区井下瓦斯精准化预抽,在综合分析煤矿瓦斯含量分布规律、有效抽采半径与抽采时间关系、以及"采-掘-抽"衔接关系基础上,从时空的角度提出了一种预抽钻孔进行分区段布置的煤矿井下瓦斯精准化预抽方法,并在黄陵矿区二号矿207综采工作面进行了现场验证试验。试验结果表明,该方法提出的钻孔分区布置方案可有效解决瓦斯抽采空白带和抽采达标问题,且明显优于统一钻孔间距6 m和12 m两种方案,较2种方案可分别节约预抽时间36、146 d,有效缓解"采-掘-抽"工程衔接不平衡,经济效益显著,实现了煤矿井下瓦斯的精准化预抽。     

余吾煤业地面钻井抽采采空区瓦斯的技术实践

针对余吾煤矿N2105工作面瓦斯涌出量大、瓦斯超限难以治理的问题,进行了地面钻井抽采采空区瓦斯的工程试验。地面钻井共抽采瓦斯27 d,累计抽采纯瓦斯19.04×104 m3,抽采期间工作面瓦斯涌出量降低约10 m3/min,且工作面瓦斯预警次数几乎为零,工作面瓦斯治理效果明显。运用FLAC3D软件研究了采动作用下套管的受力特性,结果表明钻井布置在靠近回风巷比布置在采场中部的受力要大。     

浅析中兴煤矿底抽巷布置层位优化

汾西矿业中兴煤矿可采煤层有2#、4#、5#、6#、8#、9#煤层,现开采2#煤层,为了解决上组煤瓦斯治理难题,通过分析底抽巷的优越性,结合矿井实际确定了底抽巷布置方案,并从支护成本、瓦斯治理效果、服务年限和掘进效率等方面进行了分析比较,认为底抽巷布置在4#煤层下10 m左右的砂质泥岩中对上组煤工作面开采瓦斯治理更为合理,并针对布置的层位优化巷道支护参数,保证了底抽巷施工的安全。     

高瓦斯矿井两层煤同时开采瓦斯抽采方案设计

为解决高瓦斯中近距离煤层群安全开采问题,针对阳泉大贤煤矿9号与15号煤层开采条件及瓦斯赋存特征,根据矿井瓦斯涌出量构成关系,对两层煤同时开采瓦斯抽采可行性进行分析,设计了瓦斯抽采方案,并研究确定了工作面瓦斯抽采巷道布置、抽采钻孔技术参数及采空区瓦斯抽采参数,可为类似低渗透性煤层瓦斯的治理提供很好的借鉴。     

大孔径钻孔大流量瓦斯抽采技术研究与应用

新田煤矿1901工作面为被保护层工作面,虽然通过保护层开采卸压后,但煤层瓦斯含量还是偏高,所以瓦斯治理工作任务仍然繁重,瓦斯抽采时间较长。该工作面在巷道掘进期间,经过探索研究,采取在巷道掘进面及钻场内布置大孔径钻孔,进行大流量瓦斯抽采的新技术,有效地提高了瓦斯抽采效果,确保了煤巷快速掘进。     

大直径钻孔代替横川埋管瓦斯治理技术实践

针对目前王坡煤矿横川埋管抽采存在的问题,开展了大直径钻孔代替横川埋管瓦斯治理技术探索,从施工工程量、巷道维护、抽采效果等方面,分析了大直径钻孔的技术优势;从大直径钻孔布孔设计、孔径选择、成孔工艺到钻机具选择,形成一套大直径钻孔代替横川埋管方案。通过现场试验考察,给出了大直径钻孔合理布孔间距为10 m,实现了直径550 mm钻孔一次成孔。在王坡煤矿工作面回采期间,通过大直径钻孔代替横川埋管抽采,把上隅角瓦斯浓度控制在合理区间,未出现瓦斯超限问题,解决了横川埋管抽采带来的辅助工程量大、巷道后期变形严重等问题,丰富了采空区瓦斯治理方法。     

综采工作面上隅角瓦斯治理研究与应用

综采工作面采用"U"型通风方式时,上隅角容易发生瓦斯超限,影响工作面的安全生产,是工作面瓦斯治理的难点。以平安煤矿150502工作面为工程背景,对工作面瓦斯涌出特征进行分析,发现采空区瓦斯涌出导致上隅角瓦斯积聚,确定采用设置抽采巷道布置穿层钻孔及采空区插管抽采瓦斯治理的综合方案。现场实践表明,该方案能成功降低上隅角瓦斯积聚,保障了工作面安全回采,为其他工作面上隅角瓦斯治理提供了借鉴。     

单一突出煤层底板抽放巷优化布置方案研究

为考察单一突出煤层中采用底板瓦斯巷预抽瓦斯的消突效果,在平宝公司矿井单一突出煤层下10m处布置底板抽放巷,分别提出两巷道中心对中心垂直投影距离为0、10、20m以及煤巷外帮对岩巷内帮垂直投影距离为1m等4种钻孔布置方案。结果表明：第3、第4种方案相比第1、第2种方案,每组钻孔钻进距离分别减少20-83、11-74m,施工时间分别减少100-180、80-150min,百米巷道治理周期缩短2-3d,抽放瓦斯体积分数提高10％左右。采用第3、第4种方案后,虽巷道应力分布集中、变形量较大,但通过高强锚网索支护,完全可满足安全生产需要。     

单一煤层高位瓦斯抽采巷道布置位置研究

以常村煤矿2103工作面为工程背景,在煤层开采方向,通过分析煤层基本顶的受力状态,建立基本顶岩梁断裂前夕的力学模型,求解出基本顶的周期垮落步距;利用垮落步距,引入渗透率公式,重新建立力学模型,求解岩梁内部渗透率的分布状况,并按照渗透率分类标准,将高位瓦斯抽采巷道布置在煤层透气性较好的区域。在煤层倾斜方向,建立二维模型,确定出剪切破坏带的边界,通过分析将瓦斯抽采巷道布置在剪切破坏带以外。最终确定将瓦斯抽采巷道布置在轨道运输平巷上方27.03 m,与轨道运输平巷内错29.82 m的掘进方案。给出了高位瓦斯抽采巷道实际测得的瓦斯抽采量和巷道的变形特征,表明所设计的高位瓦斯抽采巷道的位置合理,能够保证煤矿安全生产需求。     

瓦斯突出矿井预抽巷布置方法

本文针对东曲煤矿+860水平九采区瓦斯预抽巷巷道的两种布置方案,在工作面低抽巷沿不同层位进行布置以及不同施工方式、抽采进度及难易程度、所产生的经济、回采衔接效益等各方面,进行了比较分析说明,最终采用方案一即瓦斯预抽巷道布置在煤层内为最佳施工方案。     

China rare earth market review

正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.     

Current situation and future trend of China rare earth luminescent materialindustry(continued)

<正>Developing ecological lighting source The world is facing the big problem of energy shortage today and the contradiction between economy development and environmental protection is worsened.Therefore,people are more likely to choose an ecological light source that is more energy efficient and environmental friendly.The choice provides great opportunity for the development of rare earth optical material industry in China.The concept of green lighting positions rare earth luminescent material as a leading player in illumination market.The light source of both rare earth luminescent lamp and LED lamp is ecological and energy saving.This is why     

Galaxy Magnets achieved the net profit of 34.02 million yuan in the first six months of 2014

正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.     

Rare Earth Application in Steel in China

<正>China has rich rare earth resources.Output of rare earth and steel in China ranks the top first in the world.However,there is still certain distance between the steel produced in China and developed countries from the point of varieties and quality.China still has to import some types of steel.Improving the quality should be emphasiZed in future development of steel industry in China.Rare earth can be used to upgrade traditional steel     

稀散金属产业的观察与思考

分析了近年来国内外稀散金属产业的生产、应用、资源与市场状况.铟锡氧化物靶材、砷化镓晶片、锗红外材料、铼高温合金和硒在电解锰及玻璃的应用等已成为稀散金属的主要应用领域.稀散金属的产量快速增长达到历史高位而导致了市场的失衡.以GaInP_2/GaAs/Ge,CIGS和CdTe为代表的非硅系太阳能电池是稀散金属的新兴应用领域,将给稀散金属带来日益增长的需求.     

China rare earth market review

正November 1~10,2014Chinese rare earth market was still inactive.Demand for rare earth products was weak.Consumers took a wait-and-see attitude for lower price.As it was an off season for rare earth products,it was expected that prices of rare earth could continue turbulence at the bottom in short terms.Due to a sharp drop,demand for rare earth from downstream recovered.Affected by new energy vehicles,wind powder and energy-efficient appliances,production of rare earth permanent     

China rare earth market review

正August 1~10,2014 There was some good news in rare earth industry recently.Restructuring plans of rare earth groups led by Baotou IronSteel Group and Xiamen Tungsten Group respectively have been approved by MIIT.And rare earth storage policy,which had been expected for a very long time,has been launched officially.Pushed by the good news,rare earth price started to rebound since August 5.Price of didymium oxide and dysprosium oxide rose about 1% to 2%,averagely.About 10% of     

China rare earth market review

正July 1~10,2014Due to weak demand from downstream industry and slow transactions,rare earth market remained weak and price of rare earth products continued to decline.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,     

New energy vehicle:an opportunity for rare earth magnets

<正>Extracted from Securities Guide 1.Popularity of new energy vehicles—an irresistible market trend1.1 Progress of new energy vehicles Chinese Premier Li Keqiang said recently on a visit to Xi'an BYD Autos that new energy vehicles,especially new energy bus,can lessen environment and noise pollution.He encouraged the use of new     

Brief news

正Corun invested another 50 million yuan in power battery for HEV Hunan Corun announced on 27 June that they had signed the cooperation agreement to jointly built Corun(Shaoxing)Autos Power Battery System Co.,Ltd.in Shaoxing Binhai New City.According to the announcement,total registered