Mining Science and Technology (China)最新文献

{"title":"Explosive characteristics of nanometer and micrometer aluminum-powder","authors":"Jiang Bingyou ,&nbsp;Lin Baiquan ,&nbsp;Shi Shulei ,&nbsp;Zhu Chuanjie ,&nbsp;Li Wenxia","doi":"10.1016/j.mstc.2011.10.006","DOIUrl":"10.1016/j.mstc.2011.10.006","url":null,"abstract":"<div><p>The explosive characteristics of aluminum powder have great significance in preventing and controlling aluminum-dust explosion accidents, especially the nano-aluminum powder. The explosion characteristics of 100<!--> <!-->nm and 75<!--> <!-->μm aluminum powders were investigated by using a 20 L spherical explosion cavity and a horizontal pipe whose cross-section area is 80<!--> <!-->mm<!--> <!-->×<!--> <!-->80<!--> <!-->mm and length is 8<!--> <!-->m. The results show that the maximum explosion pressure and its rising rate of 100<!--> <!-->nm aluminum powder gradually increase with increasing concentration of aluminum-powder at the beginning. When aluminum-powder concentration is 1<!--> <!-->kg/m³, the maximum explosion pressure reaches its maximum, and then gradually decreases. While when the concentration is 1.25<!--> <!-->kg/m³, the maximum rate of pressure rise obtains its maximum, and then decreases. After 100<!--> <!-->nm aluminum powder is exploded in pipes, the peak overpressure of blast wave first decreases and then increases to the maximum at a distance of 298<!--> <!-->cm from the ignition source, and then gradually decreases. The most violent concentration is about 0.4<!--> <!-->kg/m³ which is lower than 0.8<!--> <!-->kg/m³ of 75<!--> <!-->μm aluminum powder, so 100<!--> <!-->nm aluminum powders are more easily exploded. The change laws of maximum explosion pressure, maximum rate of pressure rise and blast-wave peak overpressure of 100<!--> <!-->nm aluminum powders with concentration are similar to those of 75<!--> <!-->μm aluminum powders, but these values are much higher than 75<!--> <!-->μm aluminum powders under the same concentration, so the aluminum-powders explosion of 100<!--> <!-->nm will produce more harms. In the process of production, storage and transportation of aluminum powder, some relevant preventive measures can be taken to reduce the loss caused by aluminum-dust explosion according to nano-aluminum dust.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 661-666"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.10.006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75858812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Active velocity tomography for assessing rock burst hazards in a kilometer deep mine","authors":"He Hu ,&nbsp;Dou Linming ,&nbsp;Li Xuwei ,&nbsp;Qiao Qiuqiu ,&nbsp;Chen Tongjun ,&nbsp;Gong Siyuan","doi":"10.1016/j.mstc.2011.10.003","DOIUrl":"10.1016/j.mstc.2011.10.003","url":null,"abstract":"<div><p>Active velocity tomography was used to determine the stress state and rock burst hazards in a deep coal mine. The deepest longwall face, number 3207 in the Xingcun colliery, was the location of the field trials. The positive correlation between stress and seismic velocity was used to link the velocity data with stratum stresses. A GeoPen SE2404NT data acquisition system was used to collect seismic data from 300<!--> <!-->g explosive charges fired by instantaneous electric detonator and located in the tail entry. The geophones were installed on the rock bolts in the head entry of LW3207. Velocity inversion shows an inhomogeneous distribution of stress in the longwall face that could not be obtained from theory or numerical simulations. Three abnormally high P-wave velocity regions were identified that were located on the corners of the two roadways and at the face end near the rail entry side. The maximum velocity gradient is located at the open cut off near the rail entry and is the area most dangerous for rock burst. Mining-induced tremors recorded by a micro-seismic monitoring system demonstrated that the position of energy release during mining coincides with the high velocity gradient area. This technology aids technicians in the coal mine as they design measures to weaken or eliminate potential danger during subsequent mining.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 673-676"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.10.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86854442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of a cyclonic flotation column on the separation of magnesium from phosphate ore","authors":"Li Guosheng,&nbsp;Liu Jiongtian,&nbsp;Cao Yijun,&nbsp;Wang Dapeng","doi":"10.1016/j.mstc.2011.10.009","DOIUrl":"https://doi.org/10.1016/j.mstc.2011.10.009","url":null,"abstract":"<div><p>This study was performed to investigate the effects of the cyclonic separation mechanism on the removal of magnesium from phosphate ore. An analysis of the particle-bubble collision mechanism in a cyclonic force field was used to design two different pulp circulation systems for a cyclonic-static micro-bubble flotation column (FCSMC). Experiments comparing the two conditions were then conducted. Size analysis of the feed and separated products was conducted with a BXF cyclone size analyzer. The results show that about 34.60% of the total MgO content in the feed exists in the −10<!--> <!-->μm fraction. This demonstrates that magnesium removal from phosphate ore has the characteristics of a micro-fine particle flotation problem. Under conditions of cyclonic circulation the MgO level of the concentrate is 1.74%, which is lower than that obtained from the column operated in direct-flow circulation by 0.34%. These results indicate that the cyclonic circulation mechanism of the FCSMC can promote removal of micro-fine particles containing magnesium. This is attributed to the function of surface flotation and to the reduction of the lower separation limit under conditions of cyclonic circulation.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 647-650"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.10.009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91699322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parameters analysis of shearer drum loading performance","authors":"Liu Songyong,&nbsp;Du Changlong,&nbsp;Zhang Jiajia,&nbsp;Jiang Hao","doi":"10.1016/j.mstc.2011.10.005","DOIUrl":"https://doi.org/10.1016/j.mstc.2011.10.005","url":null,"abstract":"<div><p>Three drums with different helical angles (15°, 20°, and 25°) were developed to investigate improved loading performance of the shearer drum. Nine trials were performed at different drum rotation speeds (80, 100, and 120<!--> <!-->r/min) and different haulage speeds (1.5, 2.0, and 2.5<!--> <!-->m/min) in an orthogonal test design. Loaded coal quantity and cutting power of the drum were the responses measured under the different conditions. The effect of the parameters was determined by means of the extreme difference method. The significance of the effects was determined by analysis of variance. The results indicate that the effect from changes in the helical vane on loading performance of the drum is the largest in magnitude. The haulage speed has the least affect on loading performance. The helical angle has the least affect on cutting power of the drum. Haulage speed has the largest affect on the cutting power of the drum.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 621-624"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.10.005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91699319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the complex and long term swelling behavior of argillaceous rocks","authors":"Doostmohammadi R. ,&nbsp;Mutschler Th. ,&nbsp;Osan C.","doi":"10.1016/j.mstc.2011.10.007","DOIUrl":"https://doi.org/10.1016/j.mstc.2011.10.007","url":null,"abstract":"<div><p>The swelling behavior of argillaceous rocks is a complex phenomenon and has been determined using a lot of indexes in the literature. Determining the required modeling indexes that need to be performed requires expensive tests and extensive time in different laboratories. In some of the cases, it is too difficult to find a relation between the effective variables and swelling potential. This paper suggests a method for modeling the time dependent swelling pressure of argillaceous rocks. The trend of short term swelling potential during the first 3<!--> <!-->days of the swelling pressure testing is used for modeling the long term swelling pressure of mudstone that is recorded during months. The artificial neural network (ANN) as a power tool is used for modeling this nonlinear and complex behavior. This method enables predicting the swelling potential of argillaceous rocks when the required indexes and also correlation between them is unattainable. This method facilitates the model of all studied samples under a unique formulation.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 655-659"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.10.007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91699324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Parameters analysis of shearer drum loading performance","authors":"Songyong Liu, C. Du, Jia Jia Zhang, Hao Jiang","doi":"10.1016/J.MSTC.2011.10.005","DOIUrl":"https://doi.org/10.1016/J.MSTC.2011.10.005","url":null,"abstract":"","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"27 1","pages":"621-624"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77824302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of coal gangue on the level of main trace elements in the shallow groundwater of a mine reclamation area","authors":"Li Wei,&nbsp;Chen Longqian,&nbsp;Zhou Tianjian,&nbsp;Tang Qibao,&nbsp;Zhang Ting","doi":"10.1016/j.mstc.2011.03.004","DOIUrl":"10.1016/j.mstc.2011.03.004","url":null,"abstract":"<div><p>Coal gangue is the most used filling material during reclamation of areas suffering subsidence from mining. Main trace element levels (F, As, Hg, and Pb) in shallow groundwater in the reclamation area may be affected by leaching from the gangue. This can has an impact on the application of the water for agricultural irrigation or use as drinking water. Therefore, it is of great significance to understand the effect coal gangue has on the shallow groundwater of a reclaimed area. We studied the effect of coal gangue on fluorine, arsenic, mercury, and lead levels in the shallow groundwater of a reclamation area by testing the water and the coal gangue. One well near the reclamation area was used as a control well and element levels in water from this well and from the soil next to the well were also measured. The results show that the levels of these elements are increasing in the reclamation area over time. The increase in fluorine, arsenic, mercury, and lead in monitor wells varies from 7.42% to 8.26%, from 7.13% to 7.90%, from 4.85% to 6.48%, and from 4.69% to 6.42%, respectively. Fluorine and arsenic levels are lower in monitor wells than in the control water. The other elements are found in greater concentration than in the control. The Nemerow index also indicates that the shallow groundwater in the reclamation area I is moderately affected by the back-filling coal gangue, while the shallow groundwater in the reclamation area II and III are slightly affected by the back-filling coal gangue. This shallow groundwater could be used for agricultural irrigation or for drinking.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 715-719"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.03.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83634043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of sintered metal distributor on fluidization quality of the air dense medium fluidized bed","authors":"Yang Xuliang,&nbsp;Zhao Yuemin,&nbsp;Luo Zhenfu,&nbsp;Chen Zengqiang,&nbsp;Song Shulei","doi":"10.1016/j.mstc.2011.03.009","DOIUrl":"10.1016/j.mstc.2011.03.009","url":null,"abstract":"<div><p>Dry coal beneficiation using an air dense medium fluidized bed (ADMFB) requires the formation of a stable and uniform bed from the dense medium. Others have shown that the structure and geometric parameters of the air distributor have a significant influence on the experimentally observed fluidization quality. In this study we used a sintered metal distributor (SMD) in the ADMFB separator and study its effect on the fluidization quality. The results show that for the same open area ratio (OAR), a smaller aperture in the SMD will provide improved fluidization quality. If aperture size is held constant bigger open area ratios result in improved fluidization quality. And, the fluidization quality also improves when the pressure drop across the SMD increases. A model relating distributor pressure drop and the geometric parameters of the SMD is also proposed.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 681-685"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.03.009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72915524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation of the screening process on a circularly vibrating screen using 3D-DEM","authors":"Zhao Lala ,&nbsp;Zhao Yuemin ,&nbsp;Liu Chusheng ,&nbsp;Li Jun ,&nbsp;Dong Hailin","doi":"10.1016/j.mstc.2011.03.010","DOIUrl":"10.1016/j.mstc.2011.03.010","url":null,"abstract":"<div><p>A numerical study of the motion particulates follow along a circularly vibrating screen deck was done using the three dimensional Discrete Element Method (DEM). The motion of the particles was analyzed. The effects of vibration amplitude, throwing index, and screen deck inclination angle on the screening process are discussed. The results show that the average velocity of the particles increases along the longitudinal direction of the deck. The screening efficiency is highest when the vibration amplitude, throwing index, and screen deck inclination angle are 3–3.5<!--> <!-->mm, 2.7 and 15°, respectively. This work is helpful for developing a deep understanding of particle motion and for optimizing screen separator designs.</p></div>","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Pages 677-680"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.mstc.2011.03.010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84508764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"IFC: Editorial","authors":"","doi":"10.1016/S1674-5264(11)00171-2","DOIUrl":"https://doi.org/10.1016/S1674-5264(11)00171-2","url":null,"abstract":"","PeriodicalId":100930,"journal":{"name":"Mining Science and Technology (China)","volume":"21 5","pages":"Page IFC"},"PeriodicalIF":0.0,"publicationDate":"2011-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S1674-5264(11)00171-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91739604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}