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Mining Science and Technology 2009年第6期19卷 724-729页

作者： LIU Hai-bo CHENG Yuan-ping SONG Jian-cheng SHANG Zheng-jie WANG Liang National Engineering Research Center for coal ＆ Gas Control China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China zhengzhou coal industrial group corporation ltd. Zhengzhou Henan 452371 China

Numerical simulations and field tests were used to investigate the changes in ground stress and deformation of, and gas flow from, a protected coal seam under which an extra-thin coal seam was drilled. The geological conditions were: 0.5 meter mining height, 18.5 meter coal seam spacing and a hard limestone/fine sandstone inter-stratum. For these conditions we conclude: 1) the overlying coal-rock mass bends and sinks without the appearance of a caving zone, and 2) the protected coal seam is in the bending zone and undergoes expansion deformation in the stress-relaxed area. The deformation was 12 mm and the relative defor- mation was 0.15%. As mining proceeds, deformation in the protected layer begins as compression, then becomes a rapid expansion and, finally, reaches a stable value. A large number of bed separation crannies are created in the stress-relaxed area and the permeability coefficient of the coal seam was increased 403 fold. Grid penetration boreholes were evenly drilled toward the protected coal seam to affect pressure relief and gas drainage. This made the gas pressure decrease from 0.75 to 0.15 MPa, the gas content decrease from 13 to 4.66 m3/t and the gas drainage reach 64%.

关键词： extra-thin protective coal seam drilling pressure relief expansion deformation gas drainage

A comparison between DCCAE and conventional extrusion of Mg-9.5Li-3Al-1.6Y alloy

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Journal of Rare Earths 2016年第6期34卷 626-631页

作者：刘军威彭晓东王宝魏国兵谢卫东杨艳刘明朴 College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys zhengzhou coal Mining Machinery group Co. ltd.

Double change channel angular extrusion（DCCAE） was performed in dual-phase Mg-9.5Li-3Al-1.6Y（wt.%） alloy to develop fine-grained microstructures. The microstructure evolution during DCCAE and conventional extrusion（CE） was investigated. The microstructure of the extruded dual-phase Mg-Li alloy consisted of recrystallized β-Li grains, banded α-Mg phases, and Al_2Y phases distributed in β-Li phases and phase-interface uniformly. Compared with CE, the specimens after DCCAE had smaller β-Li grain size（3–5 μm by the DCCAE and 6–10 μm by the CE） and the α-Mg phases were refined during the DCCAE. The distribution of the Al2 Y phases was improved a lot by DCCAE. Furthermore, the specimens after DCCAE had better tensile strength than conventional extrusion ones.

关键词： DCCAE dual-phase Mg-Li alloy Al_2Y fine-grained rare earths

Spontaneous caving and gob-side entry retaining of thin seam with large inclined angle

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International Journal of Mining Science and Technology 2014年第4期24卷 441-445页

作者： Zhang Yongqin Tang Jianxin Xiao Daqiang Sun Lele Zhang Weizhong State Key Laboratory of coal Mine Disaster Dynamics and Control Chongqing University Sichuan Dazhu coal-Electricity group corporation Zhangji coal Mine Co. ltd. Huainan Mining Group Co. Ltd. School of Environment and Civil Engineering Wuhan Institute of Technology

Based on the research method of combining simulation analysis with field testing by distinct element process UDEC, we have analyzed the roof deformation and failure laws and roadway support technology of gob-side entry retaining in a thin seam with a large inclined angle. The results show that during exploitation in seams with large inclined angle, rotational subsidence of the main roof under the gob area is small and can maintain balance, so there is no need to provide artificial permanent support resistance for the main roof near the upper side to control rotational subsidence. Obstructed by the dense scrap rail,waste rock from the immediate roof caving slides from the upper gob area to the lower area and fills it,which strikes a balance between the immediate roof under the goaf after it fractures into large pieces and filling waste rocks.

关键词： Large inclined angle Gob-side entry retaining Spontaneous caving Thin seam Field test

CFD simulation of effect of anode configuration on gas–liquid flow and alumina transport process in an aluminum reduction cell

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Journal of Central South University 2015年第7期22卷 2482-2492页

作者：詹水清李茂周孑民杨建红周益文 School of Energy Science and Engineering Central South University zhengzhou Research Institute Aluminum corporation of China ltd.

Numerical simulations of gas–liquid two-phase flow and alumina transport process in an aluminum reduction cell were conducted to investigate the effects of anode configurations on the bath flow, gas volume fraction and alumina content distributions. An Euler–Euler two-fluid model was employed coupled with a species transport equation for alumina content. Three different anode configurations such as anode without a slot, anode with a longitudinal slot and anode with a transversal slot were studied in the simulation. The simulation results clearly show that the slots can reduce the bath velocity and promote the releasing of the anode gas, but can not contribute to the uniformity of the alumina content. Comparisons of the effects between the longitudinal and transversal slots indicate that the longitudinal slot is better in terms of gas–liquid flow but is disadvantageous for alumina mixing and transport process due to a decrease of anode gas under the anode bottom surface. It is demonstrated from the simulations that the mixing and transfer characteristics of alumina are controlled to great extent by the anode gas forces while the electromagnetic forces(EMFs) play the second role.

关键词： aluminum reduction cell anode configuration gas–liquid flow alumina transport process simulation alumina content distribution

Process-scheme-driven automatic construction of NC machining cell for aircraft structural parts

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Chinese Journal of Aeronautics 2013年第5期26卷 1324-1335页

作者： Chen Shulin Zheng Guolei Zhou Min Du Baorui Chu Hongzhen School of Mechanical Engineering and Automation Beihang University Shenyang Aircraft Industry (group) corporation ltd.

In order to enhance the NC programming efficiency and quality of aircraft structural parts （ASPs）, an intelligent NC programming pattern driven by process schemes is presented. In this pattern, the NC machining cell is the minimal organizational structure in the technological process, consisting of an operation machining volume cell, and the type and parameters of the machining operation. After the machining cell construction, the final NC program can be easily obtained in a CAD/CAM system by instantiating the machining operation for each machining cell. Accordingly, how to automatically establish the machining cells is a key issue in intelligent NC program- ming. On the basis of the NC machining craft of ASP, the paper aims to make an in-depth research on this issue. Firstly, some new terms about the residual volume and the machinable volume are defined, and then, the technological process is modeled with a process scheme. Secondly, the approach to building the machining cells is introduced, in which real-time complement machining is mainly considered to avoid interference and overcutting. Thirdly, the implementing algorithm is designed and applied to the Intelligent NC Programming System of ASP. Finally, the developed algorithm is validated through two case studies.

关键词： Aircraft structural part (ASP) Automatic programming Machining cell Process planning Process scheme Residual volume

Geochemistry of Mercury in the Permian Tectonically Deformed coals from Peigou Mine, Xinmi coalfield, China

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2243-2254页

作者： SONG Dangyu LI Chunhui SONG Boyi YANG Cunbei LI Yunbo Institute of Resource and Environment Henan Polytechnic University Collaborative Innovation Center of coalbed Methane and Shale Gas for Central Plains Economic Region State Key Laboratory of coal Resoures and Safe Mining China University of Mining and TechnologyBeijing Yanghe coal Industry Zhengzhou Coal Mining Group Co.Ltd.

As the mercury emitted from coal combustion can lead to serious environmental issues, researchers pay more attention to the content, distribution and occurrence of mercury in coal. In this paper, the content, distribution, and occurrence of mercury in the Permian tectonically deformed coals from Peigou Mine, Xinmi coalfield, Henan Province were investigated. A total of 18 bench samples were taken from No.2-1 coals seam in Peigou Mine, including 15 coal bench samples, two roofs and one floor. The mercury concentration, mineral composition, and main inorganic element content of 18 samples were determined by DMA-80 direct mercury analyzer, XRD, and XRF respectively. The results show that the mercury content ranges from 0.047 ppm to 0.643 ppm, with an average of 0.244 ppm. Though the coal seam has turned into typical tectonically deformed coal by the strong tectonic destruction and plastic deformation, the vertical distribution of mercury has remarkable heterogeneity in coal seam section. By the analysis of correlation between mercury and the main inorganic elements and the mineral composition in coal, we infer that majority of mercury mainly relates to pyrite or kaolinite.

关键词： mercury in coal minerals in coal tectonically deformed coal modes of occurrence

Experimental investigation of laser peening on TiAl alloy microstructure and properties

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Chinese Journal of Aeronautics 2015年第2期28卷 609-616页

作者： Qiao Hongchao Zhao Jibin Gao Yu Shenyang Institute of Automation Chinese Academy of Science AVIC Shenyang Liming Aero-engine (group) corporation ltd.

In order to study the effect of laser peening on microstructures and properties of TiAl alloy, TiAI alloy samples were treated by Nd：YAG laser system with the wavelength of 1064 nm, pulse-width of 18 ns, and pulse-energy of 0-10J. Surface micro-hardness, roughness, and microstructural characteristics were tested with micro-hardness tester, roughness tester and scanning electron microscope. Residual stress and pole figures were tested with X-ray diffraction and its high-temperature stability was analyzed. The experimental results show that surface micro-hardness increases by up to 30%, roughness increases to 0.37 lain, compressive residual stress increases to 337 MPa, and local texture and typical lamellar microstructure are generated. Residual stress, micro-hardness, and （002） pole figures tests are conducted, compressive residual stress value drops from 337 MPa to 260 MPa, hardness value drops from 377 HV0.2 to 343 HV0.2, and the （002） poles shift back to the center slightly. Laser peening improves microstructure and properties of TiAl alloy significantly.

关键词： High temperature stabilityLaser peening Microstructure Residual stress TiAl alloy

Slag Characteristics of Biomass Pellet Fuels with Different Additives to Tobacco-Stalk for Tobacco Curing Heating

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Energy Engineering 2024年第11期121卷 3401-3415页

作者： Jianan Wang Yikuan Fan Weidong Duan Zhaopeng Song College of Tobacco Science Henan Agricultural UniversityZhengzhou450000China China National Tobacco corporation Henan Provincial Company Zhengzhou450046China Tobacco Production Department China Tobacco Henan Industrial Co.Ltd.Zhengzhou450000China

Since pure tobacco stalk(TS)biomass pellet fuels tend to slag,five anti-slagging agents were added to the crushed TS to obtain a pellet fuel that could be used in biomass burners to provide heat for tobacco *** obtained results revealed that the main component of TS pellet fuel was K_(2)Si_(2)O_(5).During fuel combustion process,additives generated higher melting point silicate compounds by Al–K,Ca–K,and Ca–K elemental structures to replace single K elemental structure of TS,enhancing the anti-slagging efficiency of the pellet fuel from 21.63%to 78.29%and promoting the precipitation of K,Mg,and Na elements in the slag *** investigating the anti-slagging mechanism pathways of the additives in TS biomass pellet fuels,altering of the structure of silicate ion group pathway was found to improve anti-slagging effects that met the requirements of production formula.

关键词： Pellet fuel additives flue-cured tobacco heating potassium precipitation silicate

Investigation on hydrogen-induced cracking susceptibility of HG980D steel with yield strength 900 MPa

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China Welding 2008年第3期17卷 15-19页

作者：高有进王乘徐宗林 School of Hydropower and Information Engineering Huazhong University of Science and Technology zhengzhou coal Mining Machinery group Co. LTD

In this paper, the microstructure and hardness of HG980D heat-affected zone （HAZ） at different cooling rate t8/3 were studied, the implant critical fracture stress under three diffusible hydrogen conditions were measured, and the hydrogeninduced cracking （H1C） fructograph of steel HG980D were analyzed, The experimental results show that martensite exists in HAZ of HG980D till ts/3 ≥ 150 s, the harden quenching tendency of HG980D is greater; The implant critical fracture stress is related to difJhsible hydrogen content significantly, at low hydrogen level, high restraint stress is needed to nucleate HIC, the fraetograph is mainly mierovoid coalescence, bat at high hydrogen level, only small restraint stress can cause H1C occurrence, the fractograph is mainly quasicleavage. It is very important to choose ultra-low hydrogen welding consumable to weld steel HG980D to prevent hydrogen-induced cracking.

关键词： HG980D hydrogen-induced cracking diffusible hydrogen fractograph

Post-riser Regeneration Technology in FCC Unit

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Petroleum Science 2007年第2期4卷 91-96页

作者： Liu Xiancheng Lu Chunxi Shi Mingxian State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China coal to Oil ＆ Chemicals Department Shenhua Group Corporation Ltd. Beijing 100011 China

In our present work, a post-riser regeneration technology （PRRT） for fluid catalytic cracking （FCC） units was developed to deal with increasingly heavier feedstock and hereby the larger amount of coke deposited on the catalyst particles during reaction. This technology can make full use of the advantages of riser regenerator, such as high cokeburning efficiency and low residual carbon, and at the same time overcome its disadvantages, such as difficulty in starting combustion. The average particles concentration on the cross section of the system was studied on a large scale cold model experimental set-up. Also a necessary software was developed by combining the hydrodynamics research results in our work with the coke-burning kinetics model and the heat and mass transfer model developed by previous researchers. The simulation results showed that the PRRT could increase regeneration capability by 16.28%-26.24% over the conventional turbulent fluidized bed regenerator under the similar operation conditions, and that the residual carbon could be kept below 0.1 wt %.

关键词： Fluid catalytic cracking (FCC) post-riser regenerator turbulent fluidized bed regenerator FCC regenerator