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Pre-reinforcement grout in fractured rock masses and numerical simulation for optimizing shrinkage stoping configuration

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Journal of Central South University 2017年第12期24卷 2924-2931页

作者： YU Shao-feng WU Ai-xiang WANG Yi-ming LI Tao School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of High-Efficient Mining and Safety of Metal of Ministry of Education University of Science and Technology Beijing Beijing 100083 China

Proper room and pillar sizes are both critical factors for safe mining and high ore recovery rate in shrinkage stoping mining of underground metal mines. The rock masses of Tangdan copper mine of China are fractured, which needs much reinforcement and support prior to mining. Cement-sodium silicate grout technology was selected, then its related parameters such as grout pressure, diffusion radius and time were calculated and proposed. In order to test the effect of the pressured grout in the fractured No.4 ore block, field experiments were conducted. To optimize stoping configuration, three-dimensional numerical simulation with ANSYS and FLAC 3 D softwares was proposed. The results show that the drilling porosity and mechanical properties of the rock masses are increased obviously. After grout, ore recovery rate is increased by 10.2 % employing the newly designed stoping configuration compared with the previous. Last, analyzed from the surface movements, roof subsidence and the maximum principal stress of the pillars, the mining safety is probable of being ensured.

关键词： shrinkage stoping mining cement-sodium silicate grout effect of pressured grout stoping configuration three-dimensional numerical simulation

Simulation of long-distance pipeline transportation properties of whole-tailings paste with high sliming

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Journal of Central South University 2018年第1期25卷 141-150页

作者： WU Ai-xiang RUAN Zhu-en WANG Yi-ming YIN Sheng-hua WANG Shao-yong WANG Yong WANG Jian-dong School of Civil&Resources Engineering University of Science&Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Mines of the Ministry of Education(University of Science&Technology Beijing) Beijing 100083China

Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproperties of high sliming paste from a copper mine in *** on the rheological properties test,the pressure and velocity of pipeline and elbow are simulated by CFD under different mass concentrations and different stowing *** results show that the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with high sliming and pumping agent at the same mass concentration,and the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with low sliming while without pumping *** is very important to add pumping agent to whole-tailings paste with high sliming,and the resistance changes with mass concentration and stowing capacity at the same cement-to-sand ratio of1:5and tailings-to-waste ratio of6:***,the change is just limited,that is to say,the paste transportation system is of good ***,at the elbow,the maximum pressure and velocity transfer to the outside of the pipe from the ***,lubricating layer is formed at the pipe wall because of high content of fine particles in whole-tailings paste,which will protect the elbow from *** provides an intuitive and accurate basis for pipeline transportation study,and would have a wider application space in the study of paste rheological properties and resistance reduction methods.

关键词： whole-tailings paste long-distance transportation computational fluid dynamics

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供应链节点企业合作机制研究

技术经济与管理研究 2002年第2期 109-109页

作者：禹智潭吴爱祥中南大学

在供应链运作中，销售商通常根据其最初的需求预测与制造商签订合约，要求制造商建立某种产品的生产能力。如果合约可接受，制造商将建立这种生产能力。在生产能力建成后，销售商观察到实际需求，提交最后订单，制造商按最后订单组织生... 详细信息

在供应链运作中，销售商通常根据其最初的需求预测与制造商签订合约，要求制造商建立某种产品的生产能力。如果合约可接受，制造商将建立这种生产能力。在生产能力建成后，销售商观察到实际需求，提交最后订单，制造商按最后订单组织生产。在这种运作机制下，由于销售商不必支付构建生产能力的固定成本，它最初将提交一个乐观的需求预测引诱制造商建立过剩的生产能力以满足偶然出现的高需求。然而，当出现的不是高需求时，制造商过剩能力的投资将被白白浪费掉。如果制造商意识到销售商的这种动机，则以怀疑的态度对待销售商最初的预测需求，建立一个谨慎的生产能力。……

关键词：企业供应链管理协商机制合同机制供应链节点企业合作机制

Numerical study of flocculation settling and thickening of whole-tailings in deep cone thickener using CFD approach

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Journal of Central South University 2019年第3期26卷 711-718页

作者： WU Ai-xiang RUAN Zhu-en LI Cui-ping WANG Shao-yong WANG Yong WANG Jian-dong School of Civil & Resources Engineering University of Science & Technology Beijing Key Laboratory of High-Efficient Mining and Safety of Metal Mines of the Ministry of Education University of Science & Technology Beijing

Deep cone thickener (DCT) is the key equipment in cemented paste backfill (CPB), so it is essential to study the flocculation settling and thickening characteristics of the whole-tailings in DCT. Coupled with population balance model (PBM), computational fluid dynamics (CFD) was used to study the characteristics, namely particle size distribution (PSD) and underflow concentration in DCT. Based on actual production, the effects of rake rotational speed, feed rate and tailings slurry concentration were simulated and analyzed in a certain range. The PSD varied with rake rational speed, feed rate and tailings slurry concentration almost in the same trend, but the influence of feed rate was less than that of rake rational speed and tailings slurry concentration. The underflow concentration increased at first and then declined with rake rational speed and feed rate, but it rose and fell with the tailings slurry concentration. Finally, the optimal key parameters on the flocculation settling and thickening of the whole-tailings in DCT were obtained: rake rotational speed of 17 r/min, feed rate of 3.25 m^3/h and tailings slurry concentration of 20%, giving the reference values to the industrial production in Baishitamu Copper Mine.

关键词： deep cone thickener flocculation settling thickening whole-tailings computational fluid dynamics

Effect of ultraviolet mutagenesis on heterotrophic strain mutation and bioleaching of low grade copper ore

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Journal of Central South University 2017年第10期24卷 2245-2252页

作者： WU Ai-xiang HU Kai-jian WANG Hong-jiang ZHANG Ai-qing YANG Ying School of Civil and Environmental Engineering University of Science and Technology Beijing School of Resources and Environmental Engineering Jiangxi University of Science and Technology

The effect of ultraviolet mutagenesis on a heterotrophic strain(Providencia JAT-1) mutation was studied and bioleaching of low grade copper ore with mutant bacteria was investigated. The results show that the activity of bacteria was improved after ultraviolet mutagenesis; the best irradiation time was 120 s. Compared to the original bacteria, the cells density of mutant bacteria at stationary phase increased by 26% and ammonia produced by mutant bacteria increased by 12%. Higher activity of bacteria leads to a higher copper extraction rate. The bioleaching performance of Providencia JAT-1 was improved after UV mutagenesis. The copper extraction rate with mutant bacteria increased by 10.6% compared to the original bacteria. The ore surface was corroded and the fine particles were absent after bioleaching. Free copper oxide and copper silicates could be leached out easily by using JAT-1; a small part of the copper sulfide can also be leached out. Bioleaching using JAT-1 is more effective than ammonia leaching and copper extraction rate with mutant bacteria was 21.1% higher than that by ammonia leaching under the same condition.

关键词： ultraviolet mutagenesis bioleaching heterotrophic strain ammonia low grade copper ore

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左权县上武村发展核桃的经验调查

林业与社会 1999年第2期7卷 14-14页

作者：郑爱书郝炳伟吴爱祥山西省左权县林业局

上武村位于山西省左权县南部,全村202户,720口人,现有耕地59.33hm^2,1997年人均纯收入1007元,其中,果菜收入占到80％以上。核桃产出是该村农民收入的一项重点。然而近年来,1500多株挂果核桃树,年产量仅为7500kg左右,株均产量不足5kg,... 详细信息

上武村位于山西省左权县南部,全村202户,720口人,现有耕地59.33hm^2,1997年人均纯收入1007元,其中,果菜收入占到80％以上。核桃产出是该村农民收入的一项重点。然而近年来,1500多株挂果核桃树,年产量仅为7500kg左右,株均产量不足5kg,而该村曾有年产核桃2.5万kg的记载。导致产量低的直接原因是产权不稳,管理粗放。为解决产权和管理机制上的问题。

关键词：左权县核桃树早实核桃管理机制产权产量不足公开拍卖农民收入林业局滚动式发展