Mining Engineers use Whittle in open pit mines to run the economic evaluation of any mining project or operation in order to determine the investment strategy. This also enables the development of a robust mine plan that maximizes profitability by taking into account real mining constraints. In addition, Whittle can also be used to determine the orientation of the mining sequence and to minimize any risks associated to the project while maximizing the net present value (NPV).
Whittle can read block models originating from some GMPs including Surpac. In this blog, we use Whittle 4.7.3 in conjunction with Surpac 2020.1.
There are three ways how to import a block model into Whittle using Surpac.
- Users can import a block model as .mdl file which is a Surpac model
- Users can import a block model as .mod and .par files which are Whittle models
- Users can import a block model as ascii file which is .csv or text file
In this blog, we explore how to import an ASCII (csv) file as a block model into Whittle.
BLOCK MODEL VALIDATION
Mandatory attributes are:
- Density; and
- Rock types
‘’AIR’’ blocks (above topo) must have zero for density, mass, and grade values at all times.
Rock codes must have a maximum of 4 characters.
Avoiding using reserved words like ‘’ROCK’’ for rock code.
- Zone: consecutive integer
- Mining Cost Adjustment Factor (MCAF)>0
- Processing Cost Adjustment Factor (PCAF)>0
Note: No nulls and negative values for all attributes.
The ASCII file must have block indexes (I, J, K) as Whittle uses IJK. Coordinates (X, Y, and Z) are not used during the importation process.
1. Open Whittle and create a new project
2. Give a name to the project and choose where you would like to save the project.
3. Import the csv block model
4. click Next
5. Add the element then click Next
In this block model, the tonnages of blocks are defined, rock type codes are stored in the model and element in the block model is defined as grade.
N.B: blocks can be defined using ‘’density’’ if the tonnages of blocks are not defined. If blocks are defined using density, block size must be typed in. Rock type codes can be typed in and element in the block model can be defined as quantity.
6. Choose the appropriate definitions then click Next
7. Assign required fields names then click Next
8. Assign parcel information then click Next
N.B: Users can save definition
Users can click Next if they would like to set up their projects now or they can click Finish if they would like to set up their projects later.
In this blog, the author clicked Finish.
9. Whittle imports the block model.
10. Element type code is displayed.
11. Click Next then enter manually block dimensions, origin co-ordinates and mine-azimuth. In this case, there is no mine-azimuth.
12. Click Finish
In Whittle, under New Block Model node.
- Tonnage Regions
Tonnage for each rock type and total units for the element should be the same as in the GMP. In this case, Surpac 2020.1 was used as a GMP to check the tonnages and total units.