Selection of the open pit mining cut-off grade strategy under price uncertainty using a risk based multi-criteria ranking system

• Autorzy: Azimi Y. , Osanloo M. , Esfahanipour A.

Warianty tytułu

PL

Wybór strategii określania warunku opłacalności wydobycia w kopalniach odkrywkowych w warunkach niepewności cen w oparciu o wielokryterialny system rankingowy z uwzględnieniem czynników ryzyka

• Języki publikacji: EN

Abstrakty

EN

Cut-off Grade Strategy (COGS) is a concept that directly influences the financial, technical, economic, environmental, and legal issues in relation to exploitation of a mineral resource. A decision making system is proposed to select the best technically feasible COGS under price uncertainty. In the proposed system both the conventional discounted cash flow and modern simulation based real option valuations are used to evaluate the alternative strategies. Then the conventional expected value criterion and a multiple criteria ranking system were used to rank the strategies based on the two valuation methods. In the multiple criteria ranking system besides the expected value other stochastic orders expressing abilities of strategies in producing extra profits, minimizing losses and achieving the predefined goals of the exploitation strategy are considered. Finally, the best strategy is selected based on the overall average rank of strategies through all ranking systems. The proposed system was examined using the data of Sungun Copper Mine. To assess the merits of the alternatives better, ranking process was done at both high (prevailing economic condition) and low price conditions. Ranking results revealed that at different price conditions and valuation methods, different results would be obtained. It is concluded that these differences are due to the different behavior of the embedded option to close the mine early, which is more likely to be exercised under low price condition rather than high price condition. The proposed system would enhance the quality of decision making process by providing a more informative and certain platform for project evaluation.

PL

Strategia doboru granicy opłacalności (COGS) jest koncepcją mająca bezpośredni wpływ na kwestie finansowe, techniczne, ekonomiczne, środowiskowe oraz prawne związane z eksploatacją surowców naturalnych. Zaproponowano system decyzyjny umożliwiający wybór najkorzystniejszej fizycznie wykonalnej strategii doboru opłacalności wydobycia w warunkach niepewności cen. W proponowanym systemie do analizy alternatywnych strategii wykorzystuje się konwencjonalne metody oparte o analizy przepływu strumienia gotówki oraz nowoczesne techniki symulacji rzeczywistych opcji. Następnie zastosowano tradycyjny system oparty o kryterium wartości oczekiwanej oraz system rankingu wielokryterialnego do określenia rankingu strategii, w oparciu o dwie metody oceny. W systemie wielokryterialnym obok wartości oczekiwanej uwzględnia się inne dane stochastyczne określające zdolność poszczególnych strategii do generowania dodatkowych zysków, do ograniczania strat i osiągania wcześniej zdefiniowanych celów. W etapie końcowym dokonuje się wyboru optymalnej strategii w oparciu o całkowity ranking strategii uwzględnionych w systemie. Proponowane podejście testowano w oparciu o dane uzyskane z kopalni miedzi Sungun. Aby ocenić zalety najlepszej alternatywy, ranking przeprowadzono przyjmując warunki wysokich i niskich cen. Wyniki rankingu wykazały, że w warunkach różnych cen i przy zastosowaniu różnych metod oceny, uzyskane rezultaty będą się różnić. Należy wnioskować, że różnice te spowodowane są różnicami w podejściu do wbudowanej opcji wczesnego zamknięcia kopalni, która ma większą szansę na realizację w warunkach niskich cen, a nie wysokich. Proponowany system podniesie jakość procesu decyzyjnego poprzez dostarczenie platformy dodatkowych informacji dla oceny przedsięwzięcia.

Słowa kluczowe

EN

open-pit mining; cut-off grade strategy; least-squares Monte Carlo Real options valuation; multiple criteria ranking system; metal price uncertainty

PL

kopalnia odkrywkowa; strategia wyboru granicy opłacalności wydobycia; metoda najmniejszych kwadratów; metoda Monte Carlo; opcje rzeczywiste; ocena; ranking wielokryterialny; niepewność cen metali

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2012
• Tom: Vol. 57, no. 3
• Strony: 741--768
• Opis fizyczny: Bibliogr. 48 poz., rys., tab., wykr.

Twórcy

autor

Azimi Y.

• Amirkabir University of Technology, Depratment of Mining and Metallurgy, Hafez Ave., Tehran, Iran

autor

Osanloo M.

• Amirkabir University of Technology, Depratment of Mining and Metallurgy, Hafez Ave., Tehran, Iran

autor

Esfahanipour A.

• Amirkabir University of Technology, Depratment of Mining and Metallurgy, Hafez Ave., Tehran, Iran

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