A new global optimum solution model based on multi-value dynamic programming for the cut-off grade optimization in a surface mining complex

Abstract In techno-economic concern, cut-off grade (COG) optimization is the key for efficient mineral liquidation from thehuge metalliferous surface mining sector. In this paper, a sequentially advancing algorithm based on discretemulti-value dynamic programming (MDP) has been developed to calculate the global optimum COG of alarge-scale open-pit metalliferous deposit. The proposed COG optimization algorithm aims to overcome thelimitations of straightforward classical techniques in determining the optimum COG. This discrete COG-MDPmodel is the first of its kind and has the novelty of dealing with the simulation of eight dynamic possibilities toachieve the maximal global Net Present Value (NPV). A high-level programming language (Python) has been usedto develop the computer model to deal with the complexity of handling a minimum of 500 series of dynamicvariables. This model can generate results in polynomial-time from the complex of mining, milling, and smeltingand refining system corresponding to various limiting conditions. The prime objective considered in the model isto optimize the COG of a metalliferous deposit. A working open-pit copper mining complex from India has beenused to validate the model. In this study, the optimum COG for the Malanjkhand copper deposit has been found tobe (0.33%, 0.23%, 0.52%, 0.26%, 0.27%, 0.22%, 0.24%) with a maximum NPV of ₹ (12204, 14653, 16948, 14609,21454, 26717, 38821) million corresponding to various scenarios. The findings also show that the present valuegradually hits zero after the project’s life cycle, confirming the typical pattern of other mining firms.

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A sequentially advancing algorithm based on multi-value dynamic programming for the cut-off grade optimization in open-pit metalliferous deposits

10.21203/rs.3.rs-1171028/v1 ◽

2021 ◽

Author(s):

Pritam Biswas ◽

Rabindra Kumar Sinha ◽

Phalguni Sen

Keyword(s):

Dynamic Programming ◽

Net Present Value ◽

Real Life ◽

Surface Mining ◽

Life Time ◽

Copper Deposit ◽

Early Years ◽

Open Pit ◽

Present Value ◽

Copper Mine

Abstract In techno-economic concern, cut-off grade (COG) optimization is the key for efficient mineral liquidation from the huge metalliferous surface mining sector. In this paper, a sequentially advancing algorithm based on exact multi-value dynamic programming (MDP) has been developed to determine the optimum COG of an open-pit metalliferous deposit. The proposed COG optimization algorithm aims to overcome the limitations of straightforward classical techniques in determining the optimum COG. This discrete COG-MDP model is the first of its kind and has the novelty of dealing with the simulation of eight dynamic possibilities to achieve the maximal Net Present Value (NPV). A high-level programming language (Python) has been used to develop the computer model to deal with the complexity of handling a minimum of 500 series of dynamic variables with a precision value of 0.01% in grade bins. This model can generate results in polynomial-time from the complex mine, mill, and smelter and refinery system corresponding to various limiting conditions. The prime objective considered in the model is to optimize the COG of a metalliferous deposit. The model validation has been done using a real-life case study of an open-pit copper mine in India (Malanjkhand Copper Mine, HCL), considering the fixed yearly output of the mining, milling, and smelting and refining. In this study, the optimum COG for the Malanjkhand copper deposit has been found to be (0.33%, 0.23%, 0.52%, 0.26%, 0.27%, 0.22%, 0.24%) with a maximum NPV of ₹ (12204, 14653, 16948, 14609, 21454, 26717, 38821) million corresponding to various scenarios. The findings also show that the present value of net cash-flow grows in the early years, peaks at a specified mid-life time, and then drops as the reserve is depleted. The present value gradually hits zero after the project’s life cycle, confirming the typical pattern of other mining firms.

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A Dynamic-Programming Based Model for Phase-Mining Optimization in Open-Pit Metal Mines

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.316-317.896 ◽

2013 ◽

Vol 316-317 ◽

pp. 896-901

Author(s):

Qing Wang ◽

Xiao Chuan Xu ◽

Xiao Wei Gu

Keyword(s):

Dynamic Programming ◽

Net Present Value ◽

Open Pit ◽

Present Value ◽

Dynamic Nature ◽

Time And Space ◽

Full Account ◽

Metal Mines

Three important aspects of phase-mining must be optimized: the number of phases, the geometry and position of each phase-pit (including the ultimate pit), and the ore and waste quantities to be mined in each phase. A model is presented in this paper in which, a sequence of geologically optimum pits are first generated and then dynamically evaluated to simultaneously optimize the above three aspects, with the objective of maximizing the overall net present value. The model takes into full account of the dynamic nature of the problem with respect to both time and space, and is robust in accommodating different pit wall slopes and different bench heights.

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An Application of Simultaneous Stochastic Optimization at a Large Open-Pit Gold Mining Complex under Supply Uncertainty

Minerals ◽

10.3390/min11020172 ◽

2021 ◽

Vol 11 (2) ◽

pp. 172

Author(s):

Mélanie LaRoche-Boisvert ◽

Roussos Dimitrakopoulos

Keyword(s):

Stochastic Optimization ◽

Value Chain ◽

Gold Mining ◽

Net Present Value ◽

Mineral Deposit ◽

Open Pit ◽

Supply Uncertainty ◽

Geological Uncertainty ◽

Processing Facility ◽

Mining Complex

The simultaneous stochastic optimization of mining complexes optimizes various components of the related mineral value chain jointly while considering material supply (geological) uncertainty. As a result, the optimization process capitalizes on the synergies between the components of the system while not only quantifying and considering geological uncertainty, but also producing strategic mine plans, maximizing the net present value. This paper presents an application of simultaneous stochastic optimization at a large gold mining complex. The complex contains three open-pit mines, three stockpiles, a waste dump, and a processing facility. Material hardness management is integrated at the processing facility. The case study generated production schedules for each mineral deposit considered, as well as an overall assessment of the project and related forecasts. It resulted in an 18 year life-of-asset and identified the semi-autogenous grinder (SAG) mill as the bottleneck of the operation.

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A Framework for Open-Pit Mine Production Scheduling under Semi-Mobile In-Pit Crushing and Conveying Systems with the High-Angle Conveyor

Mining ◽

10.3390/mining1010005 ◽

2021 ◽

Vol 1 (1) ◽

pp. 59-79

Author(s):

Dingbang Liu ◽

Yashar Pourrahimian

Keyword(s):

Production Scheduling ◽

Material Handling ◽

Net Present Value ◽

Programming Model ◽

Mining Industry ◽

Open Pit ◽

High Angle ◽

Mine Production Scheduling ◽

Optimum Solution ◽

Sequence Requirements

In-pit crushing and conveying (IPCC) systems have drawn attention to the modern mining industry due to the numerous benefits than conventional truck-and-shovel systems. However, the implementation of the IPCC system can reduce mining flexibility and introduce additional mining sequence requirements. This paper investigates the long-term production scheduling and the crusher relocation plan of open-pit mines using a semi-mobile IPCC system and high-angle conveyor. A series of candidate high-angle conveyor locations is generated around the pit limit, with a crusher located along each conveyor line. Each conveyor location is solved independently by an integer linear programming model for making production scheduling and crushing station decisions, aiming to maximize the net present value (NPV) considering the material handling and crushing station relocation costs. The production schedule with the highest NPV and the associated conveyor and crusher location is considered the optimum or near-optimum solution.

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Phase Planning for Open Pit Coal Mines through Nested Pit Generation and Dynamic Programming

Mathematical Problems in Engineering ◽

10.1155/2021/8219431 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Xiaowei Gu ◽

Qing Wang ◽

Xiaochuan Xu ◽

Xiaoqian Ma

Keyword(s):

Dynamic Programming ◽

Net Present Value ◽

Open Pit ◽

Coal Deposit ◽

Present Value ◽

Coal Seams ◽

Column Model ◽

Coal Deposits ◽

Coal Rock

This paper presents a phase planning method specially designed for coal deposits with nearly horizontal, bedded coal seams. The geology of this type of deposit is modeled into a column model, instead of a block model, to avoid coal-rock mixing in blocks. A nested pit generation algorithm is developed for producing a series of nested, least-strip ratio pits with a column model as its input. The algorithm completely overcomes the troublesome gap problem. Taking the least-strip ratio pits as possible phase states, a dynamic programming formulation is proposed to simultaneously optimize the number of phases, the phase-pits, and the ultimate pit, with an objective of maximizing the net present value. The merits and capability of the proposed method are demonstrated through a case study on a large coal deposit.

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A Multiple Criteria Decision Making Method to Weight the Sustainability Criteria of System Selection for Surface Mining

Energies ◽

10.3390/en14113066 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3066

Author(s):

Michał Patyk ◽

Przemysław Bodziony ◽

Zbigniew Krysa

Keyword(s):

Decision Making ◽

Performance Assessment ◽

Multiple Criteria Decision Making ◽

Surface Mining ◽

Open Pit ◽

Mining Equipment ◽

Surface Mines ◽

Mining Conditions ◽

And Performance ◽

Selection Of

Selection and assessment of mining equipment used in open pit rock mines relies chiefly on estimates of overall exploitation cost. The rational arrangement of mining equipment and systems comprising loading machines, haul trucks and crushing plants should be preceded by a thorough analysis of technical and economic aspects, such as investment outlays and the costs of further exploitation, which largely determine the costs of mining operations and the deposit value. Additionally, the operational parameters of the mining equipment ought to be considered. In this study, a universal set of evaluation criteria has been developed, and an evaluation method has been applied for the selection of surface mining equipment and the processing system to be operated in specific mining conditions, defined by the user. The objective of this study is to develop and apply the new methodology of multi-criteria selection of open pit rock mining equipment based on multiple criteria decision-making (MCDM) procedures, to enable the optimization of loading, handling and crushing processes. The methodology, underpinned by the principles of MCDM, provides the dedicated ranking procedures, including the ELECTRE III. The applied methodology allows the alternative options (variants) to be ranked accordingly. Ultimately, a more universal methodology is developed, applicable in other surface mines where geological and mining conditions are similar. It may prove particularly useful in selection and performance assessment of mining equipment and process line configurations in mining of low-quality rock deposits. Therefore, we undertook to develop universal criteria and applications for the selection and performance assessment of process machines for surface mines, taking into account environmental aspects as well as deposit quality.

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Quantification of methane sources in the Athabasca Oil Sands Region of Alberta by aircraft mass balance

Atmospheric Chemistry and Physics ◽

10.5194/acp-18-7361-2018 ◽

2018 ◽

Vol 18 (10) ◽

pp. 7361-7378 ◽

Cited By ~ 17

Author(s):

Sabour Baray ◽

Andrea Darlington ◽

Mark Gordon ◽

Katherine L. Hayden ◽

Amy Leithead ◽

...

Keyword(s):

Mass Balance ◽

Oil Sands ◽

Surface Mining ◽

Open Pit ◽

Emission Rates ◽

Athabasca Oil Sands ◽

Emissions Inventory ◽

Athabasca Oil Sands Region ◽

Major Surface ◽

Tailings Ponds

Abstract. Aircraft-based measurements of methane (CH4) and other air pollutants in the Athabasca Oil Sands Region (AOSR) were made during a summer intensive field campaign between 13 August and 7 September 2013 in support of the Joint Canada–Alberta Implementation Plan for Oil Sands Monitoring. Chemical signatures were used to identify CH4 sources from tailings ponds (BTEX VOCs), open pit surface mines (NOy and rBC) and elevated plumes from bitumen upgrading facilities (SO2 and NOy). Emission rates of CH4 were determined for the five primary surface mining facilities in the region using two mass-balance methods. Emission rates from source categories within each facility were estimated when plumes from the sources were spatially separable. Tailings ponds accounted for 45 % of total CH4 emissions measured from the major surface mining facilities in the region, while emissions from operations in the open pit mines accounted for ∼ 50 %. The average open pit surface mining emission rates ranged from 1.2 to 2.8 t of CH4 h−1 for different facilities in the AOSR. Amongst the 19 tailings ponds, Mildred Lake Settling Basin, the oldest pond in the region, was found to be responsible for the majority of tailings ponds emissions of CH4 (> 70 %). The sum of measured emission rates of CH4 from the five major facilities, 19.2 ± 1.1 t CH4 h−1, was similar to a single mass-balance determination of CH4 from all major sources in the AOSR determined from a single flight downwind of the facilities, 23.7 ± 3.7 t CH4 h−1. The measured hourly CH4 emission rate from all facilities in the AOSR is 48 ± 8 % higher than that extracted for 2013 from the Canadian Greenhouse Gas Reporting Program, a legislated facility-reported emissions inventory, converted to hourly units. The measured emissions correspond to an emissions rate of 0.17 ± 0.01 Tg CH4 yr−1 if the emissions are assumed as temporally constant, which is an uncertain assumption. The emission rates reported here are relevant for the summer season. In the future, effort should be devoted to measurements in different seasons to further our understanding of the seasonal parameters impacting fugitive emissions of CH4 and to allow for better estimates of annual emissions and year-to-year variability.

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On evaluation of complex-structured coal deposits based on their typical geometric features

E3S Web of Conferences ◽

10.1051/e3sconf/202130301029 ◽

2021 ◽

Vol 303 ◽

pp. 01029

Author(s):

Alexander Katsubin ◽

Victor Martyanov ◽

Milan Grohol

Keyword(s):

Surface Mining ◽

Geological Structure ◽

Point Of View ◽

Open Pit ◽

Open Pit Mining ◽

Mining Operations ◽

Coal Deposits ◽

Geological Conditions ◽

Wide Range ◽

Large Length

Information about the geological structure of Kuznetsky coal basin (Kuzbass) allows us to note that coal deposits developed by open-cast method are characterized by complicated conditions and have the following features: large length of deposits at significant depths of occurrence; coal series bedding of different thicknesses (from 1 to 40 m); different dip angles (from 3 to 90º); a significant number of dip and direction disturbances; different thickness of unconsolidated quaternary sediments (from 5 to 40 m); a wide range of strength values of rocks. In addition, there is a thickness irregularity and frequent variability of elements of occurrence of coal seams within the boundaries of a quarry field both in length and depth of mining. From the point of view of open-pit mining, such deposits are complex-structured. The factors listed above have a decisive influence on the choice of technical means, the order of development and the possibility of carrying out surface mining operations. Therefore, there is a need for a systematization of mining and geological conditions for the development of coal deposits, the purpose of which is to ensure a process of evaluation of complex-structured coal deposits for the development of coal-bearing zones by various complexes of equipment.

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Rethinking of Construction Robot in the Whole Project Life Cycle

Journal of World Architecture ◽

10.26689/jwa.v5i1.1873 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Yvkai Zhang

Keyword(s):

Evaluation System ◽

Large Scale ◽

Global Optimum ◽

Building Performance ◽

Future Directions ◽

Modular Systems ◽

Project Life Cycle ◽

Complete Set ◽

Optimum Solution ◽

Project Life

Assistive technology and evaluation system are expected to effectively solve the challenges of using robots in construction activities and improve the efficiency and building performance. Still, challenges are still need to be addressed before using robots for construction on a large scale. This Studies were corresponded to the identified areas for further critical review, and the development of research and application in each area was systematically analyzed to identify future directions for both the academia and the industry. More speci?cally, this review focus on determining the requirement of technology and application profile for robots, and based on the above analysis, a complete set of construction framework for robot was proposed, which integrates robots and activities with the various modular systems and digital technology to get global optimum solution.

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Technological Adaptation of Internal Dumping to the Operating Mode of Open Pit when Developing Inclined and Steeply Dipping Coal Seams Strata

E3S Web of Conferences ◽

10.1051/e3sconf/202131501015 ◽

2021 ◽

Vol 315 ◽

pp. 01015

Author(s):

Alexei Selyukov

Keyword(s):

Surface Mining ◽

Operating Mode ◽

Open Pit ◽

Surface Mines ◽

Technological Adaptation ◽

Coal Deposits ◽

Mining Front ◽

Mining Methods ◽

Further Development ◽

Internal Dumping

With surface mining of inclined and steeply dipping coal deposits, the so-called deeping longitudinal mining methods with a gradual deepening of mining from the surface to the final depth are widely spread, while orienting the mining front along the strike line of the seams (strata). When using such mining methods, the volumes of internal dumping are limited or completely absent; there is a peak-like increase in overburden volumes and transportation distance, the land resources disturbing proceeds at a progressive pace. In this regard, it is obvious that an important production task is to find technological solutions and methods to develop coal deposits that reduce the environmental hazard and increase resource conservation in mining by placing overburden in the mined-out space while reducing the area for external dumps and disturbing the earth's surface. If this is not foreseen at the present time, then all coal surface mines in the coming decades will be limited by their own external dumps of overburden, and their further development will be problematic.

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