SimSched DBS
What is mine optimization and planning?
Mine optimization and planning is the most critical and important stage from the beginning to the end of a mine. Here is a short article about SimSched and its capabilities.
Mine Optimization
What is SimSched Direct Block Scheduler?
Mine optimizations will be better in the future? Yes and that’s why is SimSched help us. SimSched DBS is a plugin software that uses innovative technology for Direct Block Scheduling in open pit mining. SimSched aims to maximize the Net Present Value (NPV) of a project deciding, based on an imported block model, which blocks will be mined, when, and to which destination they must be sent.
SimSched allows to define multiple processing plants, stockpiles and waste dumps, respecting their capacities. You can also set physical limits or force mining in certain regions by importing surfaces.
Mine optimizations and algorithms…
There are may mine planning and optimization software for mining engineering. Many of them use same algorithm system which is mostly Lerchs–Grossmann algorithm for blocks.

What’s going on in the background of mine planning?
Currently, we’re able to generate pit designs that not only maximize cash flows but simultaneously define cutoff strategies, respect blending constraints, bottom widths, control deforestation areas, production by rock type, metal production, consumption of processing inputs, force/restrict mining areas, among many other restrictions.
As a mining engineer we are familiar with a number of mine planning programs. Perhaps we are working on mine designs of different mines every day. A planning engineer follows follows all steps of the design stages e.g. entering drilling data, triangulation, converting orebody to solid, block modelling (krigging or may be inverse distance weighted method or etc), pit design and so on.
Every step goes to one final destination: economic mine production, lower costs, high volume production and achivement of the highest NPV. All bosses, investors or sharehalders want to see the highest profitability in mining sector and in fact they do not really care about production or other issues. Ofcourse every engineer wants to see quick solutions on designing steps, compare to different types of results of pit and compare the parameters related to get highest rate of production.

Traditional ways…
The mine planning process is usually performed though a bottom-up strategy, whereby the final pit limit is initially defined and later the nested pits. The goal of the first stage is to determine which blocks should be mined in order to maximize profit, while respecting operational constraints (Askari And Awuah, 2009).
The technology is named bottom-up because the final pit limit is determined before the upper intermediate pits are built (Meagher and Dimitrakopoulus, 2014).
Discounted Cash Flow…
The ultimate pit limits, are the combination of blocks that maximize the total discounted cash flow of the project and respect slope constraints (Almeida, 2013). The most common strategies adopted are: Lerchs and Grossmann (LG) algorithm (Lerchs and Grossmann, 1965) and the floating cone algorithm (Pana, 1965). After determining the final pit limit, it is necessary to build the push back using the discount factor (SME, 2011). The ultimate pit is the input of a process called parameterization, which economically discretizes the space defining series of nested pits that generates increasing pit-by-pit discounted cash flow (Whittle, 1999). The parameterization approach iteratively changes the economic value of the blocks using a revenue factor and determines the ultimate pit limit based on the modified block values (Askari and Awuah, 2009).
Lerchs–Grossmann
LG is a brilliant algorithm for its time, but none of the new software need to implement it anymore. The technological advances have proven that new methods overcome some barriers that the LG faces. These days, any software that has the same mathematical model of LG implemented will rather implement an algorithm based on maximum flow rate (Max Flow) which can be run tens or hundreds of times faster than the LG. However, both LG and Max Flow have no flexibility to include other important restrictions such as a minimum pit bottom width or blending.
SimSched uses highly recommended technology currently in practice and inside research centers, being what is the most advanced, tested and available when talking about optimization. It was implemented using modern techniques based on mixed integer programming and heuristics. Its mathematical model is more realistic, for considering operational aspects and uses surfaces to return solutions that does not have any geotechnical errors. What in practice is mined are surfaces and not blocks. This type of technology has the flexibility to include other real restrictions, such as blending.
In mining, the change in technology, i.e., processes and software, does not happen fast but it takes its time, around 10 to 15 years as miners are very conservative. Indeed, throughout the years new processes and software technologies have appeared and replaced the traditional ones because of their benefits when applying them in real life.
Dr. Luis Martinez

In respect to open pit mine plan and design, the traditional optimization processes is done by following the general steps:
- Apply geostatistics (kriging) to quantify mineral resources and generate an estimated block model – delineated by blocks and benches;
- Apply the LG algorithm to generate a set of nested pit-shells – that obey physical constraint such as the slope angle;
- Delineate production phases (or cut-backs) based on tonnage analysis and by integrating sets of pit-shells;
- Delineate the ultimate pit limits – here the physical reference for mine planning are blocks, benches and phases that obey slope constraints;
- Apply cut-off grade optimisation, based on Lane’s theory, to generate the yearly (long term) production scheduling – this is done by maximising the Net Present Value (NPV) of the mine operation, considering the time value of money and obeying operational constraints such as mine, mill and refining capacities. Something important to observe is that the process of cut-off grade optimisation depends on both the ultimate pit and phase/cutback designs, which depend on the initial nested pit-shells.
Here is SimSched DBS going to the scene. With its simple interface, it quickly performs many operations in a short period of time and is almost never felt in your computer hardware.
Also you can read: SimSched DBS Tutorial
Unlike all other programs, SimSched performs many stages on your behalf. You can reach many different results by playing with only a few critical parameters in order to see how high the NPV value can be, and you can easily compare these results in the form of excel spreadsheets. The program can easily transfer tables and values as a result of each simulation.
More and how-to-use
posts are on the way.Stay on track.
If you want to learn more about what is SimSched DBS you can visit website and youtube channel clicking here.
Source:
www.simsched.com
Stochastic optimization of strategic mine planning of a hypothetical copper deposit through a parameterizable algorithm – José Mario Pareja Zapata
Direct block scheduling technology: Analysis of Avidity – REM, Int. Eng. J., Ouro Preto, 71(1), 97-104, jan. mar
Dr. Luis Martinez
Alexandre Marinho
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SimSched DBS
What is mine optimization and planning?
Mine optimization and planning is the most critical and important stage from the beginning to the end of a mine. Here is a short article about SimSched and its capabilities.
Mine Optimization
What is SimSched Direct Block Scheduler?
Mine optimizations will be better in the future? Yes and that’s why is SimSched help us. SimSched DBS is a plugin software that uses innovative technology for Direct Block Scheduling in open pit mining. SimSched aims to maximize the Net Present Value (NPV) of a project deciding, based on an imported block model, which blocks will be mined, when, and to which destination they must be sent.
SimSched allows to define multiple processing plants, stockpiles and waste dumps, respecting their capacities. You can also set physical limits or force mining in certain regions by importing surfaces.
Mine optimizations and algorithms…
There are may mine planning and optimization software for mining engineering. Many of them use same algorithm system which is mostly Lerchs–Grossmann algorithm for blocks.

What’s going on in the background of mine planning?
Currently, we’re able to generate pit designs that not only maximize cash flows but simultaneously define cutoff strategies, respect blending constraints, bottom widths, control deforestation areas, production by rock type, metal production, consumption of processing inputs, force/restrict mining areas, among many other restrictions.
As a mining engineer we are familiar with a number of mine planning programs. Perhaps we are working on mine designs of different mines every day. A planning engineer follows follows all steps of the design stages e.g. entering drilling data, triangulation, converting orebody to solid, block modelling (krigging or may be inverse distance weighted method or etc), pit design and so on.
Every step goes to one final destination: economic mine production, lower costs, high volume production and achivement of the highest NPV. All bosses, investors or sharehalders want to see the highest profitability in mining sector and in fact they do not really care about production or other issues. Ofcourse every engineer wants to see quick solutions on designing steps, compare to different types of results of pit and compare the parameters related to get highest rate of production.

Traditional ways…
The mine planning process is usually performed though a bottom-up strategy, whereby the final pit limit is initially defined and later the nested pits. The goal of the first stage is to determine which blocks should be mined in order to maximize profit, while respecting operational constraints (Askari And Awuah, 2009).
The technology is named bottom-up because the final pit limit is determined before the upper intermediate pits are built (Meagher and Dimitrakopoulus, 2014).
Discounted Cash Flow…
The ultimate pit limits, are the combination of blocks that maximize the total discounted cash flow of the project and respect slope constraints (Almeida, 2013). The most common strategies adopted are: Lerchs and Grossmann (LG) algorithm (Lerchs and Grossmann, 1965) and the floating cone algorithm (Pana, 1965). After determining the final pit limit, it is necessary to build the push back using the discount factor (SME, 2011). The ultimate pit is the input of a process called parameterization, which economically discretizes the space defining series of nested pits that generates increasing pit-by-pit discounted cash flow (Whittle, 1999). The parameterization approach iteratively changes the economic value of the blocks using a revenue factor and determines the ultimate pit limit based on the modified block values (Askari and Awuah, 2009).
Lerchs–Grossmann
LG is a brilliant algorithm for its time, but none of the new software need to implement it anymore. The technological advances have proven that new methods overcome some barriers that the LG faces. These days, any software that has the same mathematical model of LG implemented will rather implement an algorithm based on maximum flow rate (Max Flow) which can be run tens or hundreds of times faster than the LG. However, both LG and Max Flow have no flexibility to include other important restrictions such as a minimum pit bottom width or blending.
SimSched uses highly recommended technology currently in practice and inside research centers, being what is the most advanced, tested and available when talking about optimization. It was implemented using modern techniques based on mixed integer programming and heuristics. Its mathematical model is more realistic, for considering operational aspects and uses surfaces to return solutions that does not have any geotechnical errors. What in practice is mined are surfaces and not blocks. This type of technology has the flexibility to include other real restrictions, such as blending.
In mining, the change in technology, i.e., processes and software, does not happen fast but it takes its time, around 10 to 15 years as miners are very conservative. Indeed, throughout the years new processes and software technologies have appeared and replaced the traditional ones because of their benefits when applying them in real life.
Dr. Luis Martinez

In respect to open pit mine plan and design, the traditional optimization processes is done by following the general steps:
- Apply geostatistics (kriging) to quantify mineral resources and generate an estimated block model – delineated by blocks and benches;
- Apply the LG algorithm to generate a set of nested pit-shells – that obey physical constraint such as the slope angle;
- Delineate production phases (or cut-backs) based on tonnage analysis and by integrating sets of pit-shells;
- Delineate the ultimate pit limits – here the physical reference for mine planning are blocks, benches and phases that obey slope constraints;
- Apply cut-off grade optimisation, based on Lane’s theory, to generate the yearly (long term) production scheduling – this is done by maximising the Net Present Value (NPV) of the mine operation, considering the time value of money and obeying operational constraints such as mine, mill and refining capacities. Something important to observe is that the process of cut-off grade optimisation depends on both the ultimate pit and phase/cutback designs, which depend on the initial nested pit-shells.
Here is SimSched DBS going to the scene. With its simple interface, it quickly performs many operations in a short period of time and is almost never felt in your computer hardware.
Also you can read: SimSched DBS Tutorial
Unlike all other programs, SimSched performs many stages on your behalf. You can reach many different results by playing with only a few critical parameters in order to see how high the NPV value can be, and you can easily compare these results in the form of excel spreadsheets. The program can easily transfer tables and values as a result of each simulation.
More and how-to-use
posts are on the way.Stay on track.
If you want to learn more about what is SimSched DBS you can visit website and youtube channel clicking here.
Source:
www.simsched.com
Stochastic optimization of strategic mine planning of a hypothetical copper deposit through a parameterizable algorithm – José Mario Pareja Zapata
Direct block scheduling technology: Analysis of Avidity – REM, Int. Eng. J., Ouro Preto, 71(1), 97-104, jan. mar
Dr. Luis Martinez
Alexandre Marinho