Fuzzy-Based Prediction of Spatio-Temporal Distribution of Wet Muck in Block Cave Mine of PT Freeport Indonesia
Keywords:block cave, fuzzy differential equation, fuzzy logic, mud rush, predictive tool, wet muck
AbstractMud rushes, or wet muck spills, are hydro-geotechnical challenges in block cave mines where wet muck spills out of drawpoints formed by the accumulation of fine materials and water in drawbells. The purpose of this paper is to share the results of the developement of an improved predictive tool that can be used to manage wet muck spills. The tool was developed based on the hybrid modeling of wet muck distribution using fuzzy logic and fuzzy number operations. The fuzzy logic operations were applied to model the spatial distribution of wet muck classes, providing the spatial model of drawpoint status based on five contributing factors, i.e. the height of draw, the water content, the grain size of the fine material, rainfall, and no-mucking days. The fuzzy number operations were used in accordance with the mass balance principle to estimate the temporal distribution of wet muck that forms a mud deposit consisting of fine materials and water in a drawbell. The mass balance principle was expressed using the fuzzy ordinary differential equation, including the uncertainty of joining variables. A wet muck spill event at the Deep Ore Zone (DOZ) block cave mine of PT Freeport Indonesia was utilized as a case study as well as to validate the proposed method. The fuzzy-based approach shows promising results in predicting wet muck spill events.
Butcher, R.J., Stacey, T.R. & Joughin W.C., Mud Rushes and Methods of Combatting Them, Journal of The South African Institute of Mining and Metallurgy, 105, pp. 817-824, 2005.
Butcher, R.J., Stacey, T.R. & Joughin W.C., Mud Rushes in Caving Operations and Their Prevention, Proceeding of 1st International Symposium on Block and Sub-Level Caving Cave Mining, The South African Institute of Mining and Metallurgy, South Africa, 2007.
Faadhilah, I., Modeling Spatial Distribution of Wet Muck Using Fuzzy Logic - Case Study - DOZ Mine PT Freeport Indonesia, Thesis, Dept. of Mining Engineering, Bandung Institute of Technology, Bandung, Indonesia, unpublished, 2015.
Faadhilah, I., Widodo, L.E. & Widijanto, E., Modeling Spatial Distribution of Wet Muck Using Fuzzy Logic - Case Study - DOZ Mine PT Freeport Indonesia, Proceeding of International Symposium on Earth Science and Technology, Kyushu University, Fukuoka, Japan, 2015.
Hubert, G., Dirdjosuwondo, S., Plaisance, R. & Thomas, L., Tele-operation at Freeport to Reduce Wet Muck Hazards, Proceedings MassMin, The Australian Institute of Mining and Metallurgy, Melbourne, pp. 173-180, 2000.
Samosir, E., Brannon, C. & Diering, T., Implementation of Cave Management System (CMS) Tools at the Freeport DOZ Mine; Proceedings of Massmin 2004, Santiago, Chile, 2004.
Samosir, E., Basuni, J., Widijanto, E. & Syaifullah, T., The Management of Wet Muck at PT. Freeport Indonesia's Deep Ore Zone Mine; 5th International Conference and Exhibition on Mass Mining, Lule, Sweden, 2008.
Setiawan, I. & Syaifullah, T., Dewatering and Identification of Groundwater Sources at DOZ Block Cave Mine PT. Freeport Indonesia, Proceeding of Indonesian Association of Mining Professional Annual Meeting XIII, Indonesia, 2004.
Syaifullah, T., Widijanto, E. & Srikant, A., Water Issues in DOZ Block Cave Mine, PT Freeport Indonesia; Proceeding of Water in Mining Conference, Brisbane, Australia, 2006.
Ramadhan, M., Wicaksono, D., Haflil, D. & Antoro, B., New Perspective of Wet Muck Risk Map: Lesson Learned from Wet Muck Spill in Coarse Fragmentation at Deep Ore Zone (DOZ) Block Caving Mine, Papua, Indonesia, Proceedings of 24th Indonesian Mining Professionals Annual Meeting, Jakarta, pp. 198-207, 2015.
Wicaksono, D., Silalahi, P., Sriyanto, I., Soebari, L.. Ekaputra, A. & Jong, G., Potential Hazard Map for the Wet Muck Flow Prevention at The Deep Ore Zone (DOZ) Block Cave Mine, Papua, Indonesia, Proceedings of 21st Indonesian Mining Professionals Annual Meeting, Jakarta, Indonesia, 2012.
Widijanto, E., Arsana, N. & Srikant, A., Geotechnical Challenges in the DOZ Block Cave Mine, Rock Mechanics in Underground Construction ISRM International Symposium 2006, World Scientific Publishing Co. Pte. Ltd., Singapore, 2006.
Widijanto, E., Sunyoto, W., Wilson, D., Yudanto, W. & Soebari, L., Lesson Learned of Wet Muck Management in Erstberg East Skarn System of PT Freeport Indonesia, Proceeding of 21st Indonesian Association of Mining Professional Annual Meeting, Jakarta, Indonesia, 2012.
Widodo, L.E., Widijanto, E., Iskandar, I. & Notosiswoyo, S., Modeling Development of Mud Deposit for Assessment of Mud Rush Potential in Block Cave Mine, Proceeding of International Symposium on Earth Science and Technology 2014, Kyushu University, Fukuoka, Japan, 2014.
CNI, Freeport McMoran, HCI, IOZ Wet Muck Study, PT. FI Internal Report, unpublished, 1998.
Geomine & CNI, Technical Study on Condition Change of Material in Cave Causing Mud Rush Event on April 18, 2011 in DOZ Block Cave Mining - ESZ - PTFI, unpublished report, 2011.
LAPI-ITB & PTFI, Identification, Characterization, Modeling of Groundwater and Management of Inflow into DOZ Underground Block Caving Operation, Unpublished Research Report, 2012.
Zadeh, L.A, Fuzzy Sets, Information and Control 1965, 8, pp 338-53, 1965.
Mamdani, E.H., Applications of Fuzzy Algorithms for Simple Dynamic Plan; Proc. Inst. Elect. Eng, 121(12), pp. 1585-1588, 1974.
Kurtulus, B. & Flipo, N., Hydraulic Head Interpolation Using ANFIS"Model Selection and Sensitivity Analysis, Computer and Geoscience, 38(1), pp 43-51, 2012.
Dubois, D. & Prede, H., Towards Fuzzy Differential Calculus, Part 3. Diff., Fuzzy Sets and System, 8, pp. 225-233, 1982.
Gao, S. & Zhang, Z., Multiplication Operation on Fuzzy Numbers, Journal of Software, 4(4), pp 331-338, 2009.
Coutts, B.P., Susanto, H., Belluz, N., Flint, D. & Edwards, A., Geology of the Deep Ore Zone, Ertsberg East Skarn System, Irian Jaya, Proceeding of PACRIM, 10-13 October 1999, Bali, Indonesia, 1999.
PTFI-UG Geology, Study of Mud Rush Accident on April 2011, Collection of Presentations by UG-Devision, Unpublished Internal Report, 2011.
Hamrin, H., Choosing an Underground Mining Method in - Techniques in Gertsch, R.E. & Bullock, R.L. (Eds.), Underground Mining, Society for Mining-Metallurgy and Exploration, United States, pp. 45-85, 1998.
Butcher, R.J., Cunningham, R., Edwards, K., Lye, A., Simmons, J., Stegman, C. & Wyllie, A., Northparkes Mines, Rio Tinto, in Rankin, W.J. (Ed.) Monograph 28 - Australasian Mining and Metallurgical Operating Practices - 3rd Edition, The Australasian Institute of Mining and Metallurgy, Melbourne, pp. 861-878, 2013.