定向千米钻机在近水平煤层石门揭煤中的应用与探索

针对作为瓦斯突出矿井的大宁煤矿近水平煤层石门揭煤措施控制区域大、预抽钻孔施工质量要求高等问题,结合定向千米钻机轨迹可控、过程可溯的特点,提出采用千米钻机反向穿层钻孔预抽揭煤区域煤层瓦斯的技术方案。该方案实现了煤层产状的精准探测和钻孔质量的全过程管理,突破了传统揭煤措施在时间及空间上的限制,实现了区域煤层超前抽采,煤层瓦斯含量由10.25 m³/t降低至5.84 m³/t,既保证了抽采效果,又有效控制了揭煤作业时的瓦斯突出风险。     

双碳目标下煤气同采技术体系构想及内涵

“双碳”的确定对煤气同采发展理念提出了绿色低碳的新要求。立足我国以煤为主的能源禀赋特点,针对煤矿CH₄-CO₂双重碳减排技术难题,通过探究煤矿瓦斯高效精准抽采、煤矿瓦斯全浓度梯级利用及煤层CO₂捕获-封存-利用等关键技术问题,提出了以煤矿CH₄-CO₂近零碳排放为核心的全生命周期煤气同采技术体系构想,从低碳融合技术与负碳技术两方面阐述了该构想体系,并简化分析了相应的碳源汇机制。煤矿瓦斯高效精准抽采涵盖瓦斯含量精准原位测定、瓦斯涌出量精准预测、瓦斯高效抽采区域精准辨识、瓦斯抽采精准施工设计、瓦斯抽采精准增透及瓦斯抽采精准调控;在瓦斯全浓度梯级利用方面,提出了高浓度瓦斯直接利用、乏风瓦斯及低浓度瓦斯提浓增效技术为主的阶梯式综合利用体系;煤层CO₂封存作为典型负碳排放技术已处于商业运行阶段,笔者及其团队则聚焦煤矿CH₄-CO₂近零碳排放核心,提出了CO₂煤矿采空区吸储与植被固碳理念。最后阐述了双碳...     

新义矿采煤工作面区域瓦斯抽采效果研究

为了消除采煤工作面煤与瓦斯突出危险性,保证工作面接替工作的顺利进行,根据新义矿11031采煤工作面煤层赋存与瓦斯的具体情况,选择采用(本)煤层顺层平行钻孔预抽回采区域煤层瓦斯的区域防突措施。预抽工作面煤层瓦斯后结果表明:预抽钻孔布置均匀无空白带,整个回采区域划分为4个评价单元;累计抽采瓦斯量112.4万m3,抽采率达33.8%,根据瓦斯抽采量计算残余瓦斯含量为5.45⁷.16 m3/t;实测残余瓦斯含量3.897.16 m3/t;实测残余瓦斯含量3.89⁶.77 m3/t,可解吸瓦斯含量为2.696.77 m3/t,可解吸瓦斯含量为2.69⁵.57 m3/t。各项评价指标均满足《煤矿瓦斯抽采达标暂行规定》的要求,可以判定11031采煤工作面区域瓦斯抽采效果达标。     

松软低透强突出特厚煤层瓦斯治理

为了提高松软低透强突出特厚煤层瓦斯抽采效果,基于煤与瓦斯安全高效共采理论,采用保护层开采结合卸压瓦斯强化抽采技术,使高瓦斯突出煤层转变为低瓦斯非突出煤层,实现松软低透强突出煤和瓦斯安全高效共采。在崔庙煤矿进行了保护层开采试验,分析了保护层回采工作面瓦斯来源,利用分源预测法预测瓦斯涌出量并采取卸压瓦斯强化抽采技术。结果表明,保护层开采后,瓦斯抽采量由1.15 m3/min升高到4.3 m3/min且长时间保持稳定,抽采瓦斯加以利用可以取得保证安全生产、开发能源和减少环境污染三重效果,实现了煤与瓦斯安全高效共采。     

千米定向钻机在大宁煤矿瓦斯抽采中的应用

为了充分发挥千米定向钻机轨迹可控、过程可溯的特点,有效提高矿井瓦斯抽采钻孔施工效率和煤层瓦斯的抽采效果,以煤与瓦斯突出矿井大宁煤矿为例,先后在本煤层钻孔瓦斯抽采、煤层顶板穿层钻孔瓦斯抽采、岩层底板穿层钻孔瓦斯抽采等方面进行了VLD深孔千米定向钻机瓦斯抽采现场应用,实现了生产准备采区煤与瓦斯突出风险的有效管控、采煤工作面上隅角和采空区瓦斯的有效抽采、石门揭煤区和开拓煤巷煤层瓦斯的高效预抽,为安全、高效的采掘作业奠定了基础。同时针对开拓规划采区首采面布置过程中存在的诸多瓦斯治理问题,提出了千米定向钻机配合下的L形综掘工序和底抽巷穿层钻孔抽采的解决方案,有效提高了瓦斯抽采效率,降低了煤层残余瓦斯含量,保证了矿井的安全有序生产。     

定向顺层钻孔“钻-冲-护”一体化增透技术试验

针对松软低透煤层瓦斯抽采钻孔塌孔严重、瓦斯抽采效果差、抽采达标周期长、抽掘采衔接紧张等问题,基于现有装备,提出了定向顺层钻孔"钻-冲-护"一体化低透煤层高效促抽瓦斯技术,该技术在长平煤矿实践表明:大功率定向钻机施工煤段长度达到340 m,煤段水力冲孔后总返煤量260.46 t,扩孔孔径φ0.87 m。对冲孔方式进行考察,发现回转冲孔方式和交叉冲孔方式效率优于水平冲孔方式。未采取下筛管工艺抽采钻孔平均瓦斯浓度为25.05%;全程下筛管护孔抽采钻孔平均瓦斯浓度为49.10%,一体化工艺下抽采钻孔百米瓦斯纯流量比普通钻孔水力冲孔护孔后抽采钻孔百米瓦斯纯流量提高了约11倍,瓦斯流量衰减系数降低了9.4%。瓦斯抽采浓度提高约2倍,百米抽采瓦斯纯量由0.08 m³/min增至0.94 m³/min,瓦斯抽采效果明显,保障了矿井的安全高效生产。     

大宁煤矿瓦斯地质规律及防治措施研究

综合运用瓦斯地质、数理统计及矿井瓦斯防治等相关理论和方法,研究了大宁煤矿的瓦斯地质规律,分析了井田地质构造特征对煤层瓦斯赋存的影响,结果表明,煤层埋深是控制煤层瓦斯赋存的主要因素.并依据煤层瓦斯含量与煤层埋深的线性回归关系预测了大宁煤矿煤层瓦斯含量的变化趋势.在此基础上,提出了针对大宁煤矿的优化矿井通风方式,采用立体交叉瓦斯抽采措施及建立煤与瓦斯突出预警系统的瓦斯综合防治措施.     

小回沟煤矿本煤层瓦斯抽采钻孔设计研究

随着矿井采掘深度的增加,瓦斯含量及压力也随之变大。瓦斯抽采是治理矿井瓦斯最直接、最有效的手段,而抽采钻孔布置间距又是钻孔设计的重要参数。通过测定,小回沟煤矿2号煤层钻孔瓦斯抽采半径为：抽采30 d为2.22 m,抽采60 d为3.01 m,抽采90 d为3.48 m,抽采120 d为3.80 m。设计抽采钻孔间距为4 m,2204工作面原煤最大瓦斯含量为6.781 1 m³/t,抽采后煤的残余瓦斯含量最大值为5.571 2 m³/t,原煤瓦斯含量降低1.209 9 m³/t。通过优化本煤层瓦斯抽采设计达到降低煤层瓦斯含量的目的。     

低透气性厚煤层瓦斯双抽采系统优化研究

随着煤炭采深和强度的增加,多数矿井原有的1套抽采系统不能满足采掘平衡及安全生产需求,且由于采用原有系统进行高低负压(预抽、采空区抽采)抽采,导致高、低浓度瓦斯混合,不利于瓦斯的利用.鉴于此,以余吾煤矿为研究对象,将该矿现有西回风井1套地面固定瓦斯抽采系统进行优化,将其服务范围由全矿井缩小到只负责南一、南二采区的瓦斯抽采,扩建新抽采系统,采用2套管路分别建立高、低负压瓦斯抽采系统,实现全矿井高、低浓度瓦斯分源抽采,分区治理瓦斯.结果表明,该措施有效提高了瓦斯抽采率和瓦斯利用率,使高浓度瓦斯并网输送,低浓度瓦斯发电利用;同时有效解决了高瓦斯低透气性煤层采掘工作面瓦斯超限与瓦斯突出问题.     

瓦斯抽采钻孔封孔技术改进研究与应用

针对宏远煤矿系高瓦斯和煤与瓦斯突出矿井属于低透气性煤层,瓦斯抽采困难、抽采效率低、达不到燃料级浓度等问题,提高封孔质量方面采用新装备、新工艺、新方法,并改进封孔技术,提高了抽采钻孔封孔质量、单孔抽采量和整体瓦斯抽采浓度,为保障矿井安全高效生产奠定了良好基础。     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

2014 second batch of rare earth quota released

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矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586