8905

8250

كارشناسي ارشد

مكانيك سنگ

اصفهان: دانشگاه صنعتي اصفهان، دانشكده معدن

1392

ده،85ص.: مصور،جدول،نمودار

ص.ع.به فارسي و انگليسي

عليرضا باغبانان، علي احمدي عامله

سعيد مهدوري

31/2/93

لهراسب فرامرزي، محمد رئوف حسيني

مهندسي معدن

ID8250

86 Investigation into the Role of Chemo Hydro Mechanical Processes in Heap Leach Stability using Numerical Methods Roohollah Narimani r narimani@mi iut ac ir Department of Mining Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Alireza Baghbanan bagh110@cc iut ac irSupervisor Ali Ahmadi a ahmadi@cc iut ac irAbstractIn the leaching process the valuable element is transferred from the solid phase into the liquidphase via a leachate solution Heap leaching is one of the most common leaching methods in thelarge scale The safe performance of the leaching process is largely dependent on the heap stability What happens in the large macro scale of the heap is directly or indirectly depended on theprocesses happening in the small micro scale Predicting the state of the heaps after leachingimproves the design and management of the overall structure of the heap The main goal of thisresearch is to have a better understanding of the mechanical behavior of the heaps before and afterthe utilization In this regard the coupled f chemo hydro mechanical process involved in the fieldof the heap 4 of Sarchesmeh Mine is modeled using the numerical and experimental methods The results of experiments conducted on the heap soil before and after the simulated leachingprocess indicates that the soil grains density and size decreases While the grain size distributiondoesn t change significantly The results of the direct shear tests on the leached test samplesindicated a decrease of about 4 6 degrees in the internal friction of the soil After conducting the experiments the accumulation and the leaching of the soils in the heap andtheir effect on the stability were modeled using PFC 2D in the 2D state increasing the layers andtheir height in the steep beds increases the possibility of instability In the current situation of heap4 of Sarchesmeh Mine at a height of 4 5 m in the bed dip nd 14 rd of there is a significant decrease in nd rdthe angle of repose of 2 and 3 layers The situation of 2 and 3 layer of the heap in the heightof 6 5 m and the bed dip of 8 indicates a decrease of 1 2 5 to 1 3 5 angle of repose In the bed dipof 14 and the height of 6 5 m 2nd layer is considered to be nd critical After finishing the leaching of 4layers in in the bed dip of 14 and the height of 10 m the 2 layer slips It seems that the leachingin small scale and in the lower height layers doesn t have a destructive effect on the heap stability Increasing the height and the number of layers while increasing the bed dip makes the stability acritical issue Keywords Heap Leaching Coupled processes Angle of repose size distribution PFC

عليرضا باغبانان، علي احمدي عامله

سعيد مهدوري

لهراسب فرامرزي، محمد رئوف حسيني