Simulation-based decision-making system for optimal mine production plan selection

Price uncertainty is one of the major uncertainties in the life of mine (LOM) planning process which can have a decisive effect on the overall profitability. Today’s mine planning software tools provide block-sequencing optimisation for a given static price assumption that is then used as a basis of managerial decision-making process. This paper proposes a complementary approach to this by introducing a simulation-based decision-making tool that, with the help of simulation, seeks for the optimal mine plan when a managerially estimated price development with minimum and maximum boundaries is used as a data input for the given period. To demonstrate the approach, a realistic gold mine case study is presented with five alternative and technically feasible mine plans calculated in a static optimiser from a commercial mine planning software package. These mine planning scenarios are then subjected to price uncertainty in simulation with and without a price trend assumption to highlight the effect of price on the mine’s expected performance. Based on the results, we derive and demonstrate a simulation-based system that automates the matching of optimal mine plan with the managerial insight of long-term price development.

Evaluasi produksi penambangan batubara di PT Hamparan Mulya, Provinsi Kalimantan Tengah

PT Hamparan Mulya memiliki 2 pit, yaitu Pit Alfa dengan luas sebesar 8,4 Ha dan Pit Clara dengan luas sebesar 31,8 Ha. Sebelum melakukan suatu kegiatan penambangan, PT HM membuat perencanaan yang matang serta perancangan suatu sistem dan tata cara penambangan. Setelah itu perlu dilakukannya evaluasi dari perencanaan dan perancangan tersebut yang sudah terlaksana di lapangan untuk mengetahui ada atau tidaknya target produksi yang tidak tercapai dari data mine plan periode Mei 2017, sekaligus mencari faktor-faktor apa saja yang mempengaruhi ketidaktercapaian tersebut.Penelitian ini dilakukan dengan mengumpulkan data primer dan sekunder memakai dua cara, yaitu pengamatan lapangan dan penggunaan data perusahaan. Pengolahan data dilakukan dengan bantuan software Ms.Excel 2016, Map Source, ArcGIS ArcMap 10.3, dan Surpac 6.3 dengan melakukan penyusunan laporan yang menyajian peta, gambar, tabel, dan grafik. Analisis data dilakukan terhadap hasil pengolahan data dan analisa pembahasan dilakukan dengan cara mengkorelasikan hasil pengolahan data dengan masalah yang diteliti.Pembongkaran overburden (OB) pada Pit Alfa dan Pit Clara sudah tercapai sesuai target plan dengan total volume sebesar 341.079 BCM dan 96.063 BCM, sedangkan penggalian batubara (coal) pada Pit Alfa tidak tercapai sesuai target plan dengan total tonase sebesar 42.714,87 ton dan pada Pit Clara sudah tercapai sesuai target plan dengan total tonase sebesar 60.267,69 ton. Target produksi (gabungan kedua pit) untuk pembongkaran overburden (OB) sudah tercapai, sedangkan untuk penggalian batubara (coal) masih belum tercapai dikarenakan adanya ketidaktercapaian target plan perpit pada Pit Alfa. Luas area yang tergali pada kegiatan penambangan di Pit Alfa adalah seluas 7,4 Ha dan di Pit Clara adalah seluas 3,9 Ha. Kata-kata kunci: mine plan, penggalian, pit

A Review of Models and Algorithms for Surface-Underground Mining Options and Transitions Optimization: Some Lessons Learnt and the Way Forward

It is important that the strategic mine plan makes optimum use of available resources and provides continuous quality ore to drive sustainable mining and profitability. This requires the development of a well-integrated strategy of mining options for surface and/or underground mining and their interactions. Understanding the current tools and methodologies used in the mining industry for surface and underground mining options and transitions planning are essential to dealing with complex and deep-seated deposits that are amenable to both open pit and underground mining. In this study, extensive literature review and a gap analysis matrix are used to identify the limitations and opportunities for further research in surface-underground mining options and transitions optimization for comprehensive resource development planning.

EVALUASI DESAIN BULANAN TERHADAP KONDISI AKTUAL DI PIT 10 (PT BTS) PADA IUP PT BINUANG MITRA BERSAMA

PT Berkat Tambang Sejahtera kontraktor dari PT Binuang Mitra Bersama, dalam kesempatan ini digunakan untuk mengevaluasi antara rencana penambangan dengan kondisi aktual Perencanaan tambang adalah tahapan penting dalam studi kelayakan dan rencana operasi penambangan. Tujuan dari penelitian ini ialah membandingkan volume overburden dan batubara antara rencana dengan aktual pada bulan Juni 2019, menganalisis ketercapaian volume overcut dan undercut antara desain bulanan dengan kondisi aktual bulan Juni 2019, membandingkan volume overcut dan undercut bulan Juli dengan bulan Juni. Metode yang dilakukan dalam penyelesaian penelitian ini ialah observasi lapangan, data primer, jumlah fleet. seperti data curah hujan, peta kemajuan tambang, mine plan design, data aktual overburden, coal, dan data plan overburden serta data plan coal. Pengolahan data dilakukan dengan tahapan melakukan penggabungan antara peta kemajuan tambang dengan peta desain bulanan. Perhitungan pada bulan Juni didapatkan hasil volume overcut 10.175.06 BCM untuk tanah penutup dan 3.350,50 ton untuk batubara. Volume undercut 58.482.65 bcm untuk tanah dan 6.078.00 ton untuk batubara.sedangkan pada bulan Juli didapatkan volume overcut 11.508,73 bcm untuk tanah dan 4.320,52 ton untuk batubara. Volume undercut 79.281.60 bcm untuk tanah dan untuk batubara pada bulan Juli melebihi rencana yang telah ditentukan sebesar 4.320.52 ton. Kata kunci : Perencanaan, Desain Bulanan, Topo aktual, , Total Volume

Accounting for operational dilution by incorporating geological uncertainties in short-term mine planning

Operational dilution in open-pit mining can influence short-term mine planning and affect the adherence between designed and executed plans, impacting the reconciliation results. This type of dilution may occur due to several reasons, such as erroneous assumptions regarding contacts, inefficient mining performance, and uncertainties associated with the planned grades. The use of uncertainties enables better predictability and achievement of planned targets. Using the mine planning polygons and grade models, a methodology is proposed to measure the dilution ranges in each region. The methodology considers the uncertainty associated with the ore grades to verify the probability of occurrence of dilution in the short-term mine plan. The results demonstrated that the use of uncertainties enabled identification of the areas with a higher potential of incurring operational dilution. Using this information, the plans can be adjusted to minimize dilution, or the result can be used as a factor to correct the planned data.

Relationship between pit slope design and coal reserve estimation in Pit X, Muara Enim, South Sumatra Province

Mine planning is an important part of mining activity. Improper mine plan will increase production costs, non-optimal extraction of mines and safety factors that do not meet the standard. One of the most important aspects before undertaking mine plan is determining the optimal slope design as a basis for making mine pits for coal extraction. This study aims to estimate the maximum reserves that can be taken from the mine pit by taking account of the safety factor of the pit slope design. The study was conducted using drill log data and rock engineering characteristics. Analysis of slope stability is done using the Rocscience Slide V.6 software while coal reserves estimation is done using Minescape V.5.2. Slope stability analysis is modeled with several scenarios of slope angles until a single optimal slope angle is obtained, with the value of the slope safety factor that meets the safety criteria. The results showed that the maximum single slope angle in a safe pit was 52° with a safety factor of 1.266, while the coal reserves obtained with the said slope angle are 29, 965, 008 tons.