SciELO - Scientific Electronic Library Online

 
vol.109 issue7Impact of deep-hole opencast blasting on the stability of water dams of a close-by underground coal mine author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Journal of the Southern African Institute of Mining and Metallurgy

On-line version ISSN 2411-9717

J. S. Afr. Inst. Min. Metall. vol.109 n.7 Johannesburg Jul. 2009

 

TRANSACTION PAPER

 

Development of a gravity flow numerical model for the evaluation of drawpoint spacing for block/panel caving

 

 

R.L. CastroI; F. GonzalezII; E. ArancibiaIII

IMining Engineering Department, Mining Technology Center, University of Chile, Santiago, Chile
IIMining Engineering Department, University of Chile, Santiago, Chile
IIICodelco, Chile

 

 


SYNOPSIS

Block caving methods, when operated under favourable rock mass conditions, can achieve higher production rates and lower operating costs than other various existing underground mining applications. For this reason, it has been considered the preferred method for the mining of deep and large orebodies in current and future operations around the world. One of the key aspects in the design of block caves is the selection of the production level layout, which, among other parameters, is based on the gravity flow characteristics of the caved rock. This is because gravity flow has a large impact on total ore recovery and the amount of dilution in a caving operation. Today, there are a number of computer based methods which aim to emulate the gravity flow pattern of the caved rock.
In this paper, the authors present the development of FlowSim an improved model of gravity flow based on the cellular automaton approach, to estimate dilution entry, mixing and ore recovery. As part of the model development, flow simulations were conducted and subsequently compared to full-scale data collected at two mine sectors operated by Codelco Chile. The results indicate that by using proper calibrated parameters, good correlations between simulated and measured grades as well as dilution entry are obtained. The potential use of the numerical tool to evaluate drawpoint spacing in terms of recovery and dilution for block/panel caving operations is also presented.


 

 

“Full text available only in PDF format”

 

 

References

1. LAUBSCHER, D. Cave mining - the state of the art. Journal of the South African Institute of Mining and Metallurgy, 1994, pp. 279-293.         [ Links ]

2. LAUBSCHER, D. Block Caving Manual. International Caving Study Report. JKMRC and Itasca Consulting Group Inc., Brisbane, 2000.         [ Links ]

3. TRUEMAN, R., CASTRO, R.L., and HALIM, A. Study of multiple draw zone interaction in block caving mines by means of a large 3D physical model. International Journal of Rock Mechanics and Mining Sciences, 2008. vol. 45, pp. 1044-1051.         [ Links ]

4. CASTRO, R., TRUEMAN, R., and HALIM, A. A study of isolated draw zones in block caving mines by means of a large 3D physical model. International Journal of Rock Mechanics and Mining Sciences, 2007. vol. 44, pp. 860-870.         [ Links ]

5. CASTRO, R. Study of the Mechanisms of Gravity Flow for Block Caving. PhD Thesis, University of Queensland.         [ Links ]

6. HESLOP, T.G. and LAUBSCHER, D. Draw Control in Caving Operations on Southern African Chrysotile Asbestos Mines.Design and operation of caving and sublevel stoping mines, NewYork, D. Stewart (ed.). Society of Mining Engineers -AIME, 1981, pp. 755-774.         [ Links ]

7. DIERING, T. PC-BC: A Block Cave Design and Draw Control System. Proceedings of MassMin 2000, Brisbane, G. Chitombo, (ed.). The Aus. Inst of Min & Met., 2000, pp. 469-484.         [ Links ]

8. CUNDALL, P.A. and STRACK, O.D.L. A discrete numerical model for granular assemblies. Géotechnique, 1979, vol. 29, pp. 47-65.         [ Links ]

9. PIERCE, M.E., CUNDALL, P.A., VAN HOUT, G.J., and LORIG, L. 2003. PFC3D modeling of caved rock under draw. Numerical Modeling. Micromechanics via Particle Methods, Konietzky, (ed.), pp. 211-217.         [ Links ]

10. CUNDALL, P, MUKUNDAKRISHNAN, B., and LORIG, L. REBOP (Rapid Emulator based on PFC3D) Formulation and User's Guide. JKMRC & ITASCA Consulting Group, Inc., Brisbane. 2000.         [ Links ]

11. JOLLEY, D. Computer simulations of the movement of ore and waste in an underground mine. CIMM Bulletin, 1968. vol. 61, pp. 854-859.         [ Links ]

12. GUSTAFSSON, P. Waste rock content variations during gravity flow in sublevel caving: Analysis of full-scale experiments and numerical simulations. PhD Thesis, Universitetstryckeriet Lulea, Lulea, 1998.         [ Links ]

13. ALFARO, A. and SAAVEDRA, J. Predictive models for gravitational flow. Proceedings of MassMin2004, Santiago, Chile, A. Karzulovic and A. Alfaro (eds.), 179. Chilean Engineers Institute. 2004.         [ Links ]

14. RAÑA, F., TELIAS, M., and VICUÑA, M. Controlled draw in block/panel caving. Proceedings of MassMin2004, Santiago, Chile, A. Karzulovic and A. Alfaro (eds.), 474. Chilean Engineers Institute.         [ Links ]

15. NEDDERMAN, R.M. Statics and kinematics of granular materials. Cambridge University Press, 1992. 351 pp        [ Links ]

16. MELO, VIVANCO, FUENTES. Calculated isolated extracted and movement zones compared to scaled models for block caving. International Journal of Rock Mechanics and Mining Sciences, 2009. vol. 46, pp. 731-737.         [ Links ]

17. DÉSÉRABLE, D. A Versatile Two-Dimensional Cellular Automata Network for Granular Flow. J. App. Math., 2002. vol. 62, pp. 1414-1436.         [ Links ]

18. SHARROCK, G., BECK, D., BOOTH, G., and SANDY, M. Simulating gravity flow in sublevel caving with cellular automata. Proceedings of MassMin2004, Santiago, A. Karzulovic and A. Alfaro, (eds.), 189. Chilean Engineers Institute. 2004.         [ Links ]

19. BAXTER, G. and BEHRINGER, R.P. Cellular automata models of granular flow. Physical Review A, 42: 1990. pp. 1017-1020.         [ Links ]

20. LITWINISZYN, J. The Model of a Random Walk of Particles Adapted to Researches on Problems of Mechanics of Loose Media. Bulletin de L' Académie Polonaise des Sciences Techniques, vol. XI: 1963. pp. 593-602.         [ Links ]

21. MULLINS, W.W. Stochastic Theory of Particle Flow under Gravity. Journal of Appiled Physics, vol. 43, 1972. pp. 665-678.         [ Links ]

22. VERDUGO, R. and UBILLA, J. Geotechnical analysis of gravity flow during block caving. Proceedings of MassMin2004, Santiago, A. Karzulovic and A. Alfaro, (eds.), vol. 195. Chilean Engineers Institute.         [ Links ]

23. KVAPIL, R. Sublevel Caving. SME Mining Engineering Handbook, 2nd edition, Hartman, H.L. (ed.). Society for Mining Metallurgy and Exploration: Littleton, Colorado, 1992. pp. 1789-1814.         [ Links ]

24. BAK, M., TANG, C., and WIESENFELD, K. Self-Organised Criticality. Physical Review A, vol. 38: 1988. pp. 364-374.         [ Links ]

25. RODRIGUEZ, F. Personal communication, 2008.         [ Links ]

26. BARRAZA, M. and CRORKRAN, P. Esmeralda Mine Exploitation Project. Proceedings of MassMin 2000, Brisbane, Australia, G. Chitombo. (ed.), the Aus. Inst. of Min & Met. 2002.         [ Links ]

27. DIDYK, M. and VASQUEZ, G. Draw Behavior in El Salvador Mine. Design and operation of caving and sublevel stoping mines, New York, Stewart, D. (ed.), Society of Mining Engineers -AIME, 1981. pp. 737-743.         [ Links ]

Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License