首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
Institute of Mining, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 4, pp. 77–85, July–August, 1991.  相似文献   

3.
4.
王滨  高立堂  吴涛 《工程建设》2007,39(2):18-21
对某厂房预制钢筋混凝土吊车梁进行了正常使用极限状态的性能检测,并详细介绍了试验的实现方法以及对有关检测规范的具体运用。  相似文献   

5.
对某厂房预制钢筋混凝土吊车梁进行了正常使用极限状态的性能检测,并详细介绍了试验的实现方法以及对有关检测规范的具体运用。  相似文献   

6.
7.
内蒙古某银多金属矿为缓倾斜矿脉,采用浅孔房柱法采矿。经过多年开采,井下形成大面积采空区,空区内遗留部分点柱矿量。为消除空区隐患,矿山进行了采空区综合治理研究。利用FLAC3D软件,对不同的治理方案和施工顺序进行数值计算模拟,分析治理过程中采空区围岩应力和位移变化,最终确定安全高效的治理方案。根据数值模拟结果,选择隔一充一间隔充填法在空区充填的过程中回收点柱方案,能够在空区治理的过程中有效控制围岩变形、控制地表塌陷、保障施工安全,为类似矿山大型采空区治理提供了参考依据。  相似文献   

8.
9.
《Minerals Engineering》1999,12(7):757-768
The “Barreiro” carbonatite complex is located in Araxá, MG, Brazil. The production of apatite concentrate from this ore started in 1978 and the current production capacity is 800,000 tonnes.The ore is subjected to the following unit operations in the concentrator: grinding, classification, low field magnetic separation, desliming, apatite and barite flotation, high field magnetic separation, filtration and drying.Barite and apatite flotations were performed in 300 ft3 (8.5 m3) Wemco mechanical cells until 1992. The replacement of the mechanical cells by flotation columns occurred in two stages: fine fraction flotation circuit in 1993 and coarse fraction flotation circuit in 1994. All the 66 mechanical cells were replaced by 6 flotation columns (3.0 m × 4.5 m × 14.5m), resulting in improved selectivity and recovery and significant reductions in the consumption of the collectors for barite and, mainly, for apatite.The flotation process control monitoring in laboratory bench scale mechanical cells was then inadequate due to the discrepancy with the industrial practice. A specific methodology was developed for batch column flotation testing. The technique was checked by means of comparison with the industrial plant practice of apatite and barite flotation, showing its reproducibility and reliability for process development testwork.The batch flotation column was utilised to evaluate the effect of ions (dosed in the conditioning stage) on the flotation of barite and apatite. Flotation tolerance limits were established for the ions calcium, magnesium, phosphate, fluoride and rice bran oil soaps. Due to the fact that these ions were dosed as sodium salts (in the case of anions) or as chlorides (in the case of cations), the effect of sodium and chloride ions was also assessed (tests with the addition of sodium chloride).The results led to the environmental benefit of a full process of water recirculation in the concentrator without impairing the flotation performance.  相似文献   

10.
Institute of Mining, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 109–113, January–February, 1989.  相似文献   

11.
12.
13.
王灿霞  庞建涛  肖喆  杨稳权  张华 《矿冶》2021,30(1):99-106
利用偏光显微镜、能谱仪、扫描电镜、XRF及MLA系统等对越南某磷矿进行了工艺矿物学研究.结果表明,该磷矿中P2O5含量为21.85%,为低品位磷矿,有害元素主要为SiO2,含量为34.73%,工业类型为硅质及硅酸盐型磷块岩;P2Os主要赋存在碳氟磷灰石中,少量赋存在银星石中;矿样中碳氟磷灰石主要为碎屑状、自形短柱状、微...  相似文献   

14.
15.
16.
In a semiarid climate where the annual precipitation is low and the evaporation rate is high, contaminated drainage production from mine tailings can be controlled by reducing water infiltration. Store-and-release covers that use capillary barrier effects can prevent water percolation by storage and evaporation (or evapotranspiration) during wet and dry climatic periods. In Morocco, sedimentary phosphate mines are located close to contaminated sites, which includes the abandoned Kettara mine. This mine site generates highly contaminated acid rock drainage (ARD) with negative impacts on its surrounding area. In order to validate if phosphate mine wastes can be used as cover material to reclaim the Kettara site, instrumented test columns were exposed to field conditions and tested for a period of one and a half years. Under natural conditions, more than 94 % of the total net infiltration (246.5 mm) was released to the atmosphere by evaporation. Preliminary tests showed that the studied scenarios can limit deep water infiltration even during extreme simulated rainfall (155 mm/d) and could be used to efficiently control contaminated drainage in a semiarid climate.  相似文献   

17.
18.
19.
Conclusions On the basis of the mathematical model here proposed for the action of the explosion of two cylindrical (borehole) explosive charges in the scarp of a rock mass, the scope for investigating the correlation between wave propagation parameters with scarp rock cutting in a pit is expanded. This offers the possibility of solving a series of problem associated with the correction of wave propagation parameters and their optimization in conditions of open-pit mining of minerals. Mining Institute, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 33–38, March–April, 1986.  相似文献   

20.
为了判明某滨海城市入侵海水的来源,对其沿海典型地段进行地下水取样,通过对所取水样的主要离子和同位素的分析,绘制了地下水中主要阴阳离子与氯离子浓度间的双变量图.主要阴阳离子与氯离子的相关性说明了研究区地下水化学成份中的变化主要是由于海水与地下淡水混合引起的离子交换造成的,同时Br-/Cl-的比值说明了入侵咸水来自于现代海水,氢、氧同位素的关系也说明了研究区地下咸水是由于海水和淡水的混合形成.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号