Export To Whittle [PDF]

Citation preview

Export to Whittle You use this function to convert a block model into a format suitable for Whittle to perform an open-pit optimisation. This function outputs a Whittle .mod and/or .pil file directly from a (loaded) Surpac block model. This function uses data in several block model attributes to determine if a block could be potentially processed, and outputs a Whittle block model file dependant on attributes containing grade, specific gravity and other information. Optionally, you may also perform validation on the model before output of the Whittle file. This will increase the processing time required, but will prevent Surpac from trying to produce an invalid Whittle block model file. To run this function:Block Model > Block Model > Export > to Whittle, or  In the Function Chooser, type BM OUTPUT WHITTLE and press ENTER. Fields on the Export to Whittle four-x form Field Description Standard Output Options Constrain  Selected: Constrains the block model, cutting down the number of blocks in the output. Model  Cleared: Uses all of the blocks in the block model. Export Block Selects the block size at which the Whittle model will be exported. An example value is 0.5, 0.5, 0.5. Size (X, Y, Z) SG attribute The attribute storing a specific gravity value for each block, for example sg. Mine number The attribute containing the mine number. This is an optional field and can be left blank. attribute Rounding Options The number of decimals used when calculating block tonnage and metal content. Note: If you export to free file format, 3 decimal points are always used. One reason for specifying fewer Decimals decimal places is to prevent data 'overrun' in a block model report for a fixed file format, that is, to prevent values in the report extending beyond their allocated space and over the top of other values. Mod File  Selected: Exports a .mod (Whittle block model) file. This is enabled by default. Generate mod file  Cleared: Does not export a .mod file. Model file The name of the output model file. It is given a .mod extension. name Parameter file The name of the output parameter file. It is given a .par extension. name The attribute that contains a character rock code for each block. An example value is rock. Rock code Note: This attribute must not contain any NULL values. attribute The attribute containing a Mining Cost Adjustment Factor for each block, or a numeric value (greater than 0) to MCAF attribute be applied to all blocks. The attribute containing a Processing Cost Adjustment Factor for each block, or a numeric value (greater than 0) PCAF attribute to be applied to all blocks. The attribute containing the zone number. This field is used to define different slope regions that can use Zone attribute separate slope profiles within Whittle. This is an optional field and can be left blank. Block value The attribute containing the block value. This is an optional field and can be left blank. attribute The volume adjustment factor attribute. This is an optional field and can be left blank. The volume adjustment attribute is used to modify the ore tonnes in a block but NOT the total block tonnes. This Volume attribute is a factor less than one i.e. 0.8 not 80%. If the block has 100t @ 2 g/t, without the volume adjustment adjustment the ore parcel contains 100t @ 2 g/t for 200g. If the volume adjustment was 0.5 then the total block tonnes remain 100t while the parcel contains 50t @ 2 g/t for 100g. Waste rock The rock code that is "undefined waste". code Air rock code The rock code that is air. Validate Model  Selected: Validates the block model for Whittle output, preventing an invalid model from being exported. This option is the equivalent of running BM VALIDATE FOR WHITTLE OUTPUT function.



 Cleared: Does not validate the block model for Whittle output. Error lookup The attribute to contain the error code(s) if validation fails. It is recommended that you create a new attribute for attribute this purpose, because the function will over-write any existing values for this attribute. Error report file The name of the report text file to output. This report contains the successful tests as well as failed test name information. Output report The name of the report text file to output, this will contain the successful tests as well as failed test information. file format Indicator Indicates whether or not the model to be exported is an Indicator Kriged (IK) model. If selected, the Enter Kriged indicator kriging values form will be displayed following this form. Grade The names of one or more attributes that contain the grade values to be exported to Whittle. This table is Attributes displayed if the Indicator Kriged field is not selected. Generate  Selected: Generates a Whittle style report. This is disabled by default. report  Cleared: Does not generate a Whittle style report. Export report The name of the report text file to export to Whittle. filename The file format for your output. Options are:  .not: Note File  .csv: Comma Separated (Spreadsheet)  .htm: Hypertext Markup Language (Web) Output report file format  .html: Hypertext Markup Language (Web)  .rtf: Rich Text Format (Microsoft Word)  .pdf: Adobe Acrobat  .ps: Postscript Pit List File  Selected: Exports a .pil (Whittle pit list) file. This is disabled by default. PIL files are used to export a pit Generate pit design from Surpac to Whittle and allow further scheduling and financial analysis in Whittle. list file  Cleared: Does not export a .pil (Whittle pit list) file. Pit list file The name of the pit list file to output. name The attribute containing the pit number. If there are several cutbacks before the final pit then a block falling Pit number inside the final pit should have the number of the lowest pit (which would be mined first). Pit numbers should be attribute sequential and start at 1. If a block is not located within the final pit, it should have a NULL value or be given the final pit number plus one. Output This command outputs a Whittle .mod, .par, and / or .pil file. The output depends on the options chosen (i.e. either to generate a .mod file or a .pil file). There are a number of other reports (validation and export reports) that can also be generated during this process depending on the options chosen. Model Preparation To output a correct Whittle file, correct and useful data must first exist in the block model. If the data in the block model is not correct, the Whittle model will not make sense, or it will be incorrect. Therefore, good model preparation is essential. Note: To conform to guidelines issued by most professional institutions, it is important that you only include mineralised material which is classified as 'measured' or 'indicated' in the pit optimisation process. Material in the 'inferred' category should be ignored for the purpose of pit optimisation. Filling the block model attributes with reasonable data is the most difficult part of the interface. But here are some suggestions:  Ensure all blocks above the topography have zero density and zero grades.  Ensure that all blocks below the topography do not have zero density, except where modelling voids.  If using zone numbers to model different slope regions, ensure that all blocks in the model are assigned a slope region.  Ensure all blocks in the model are assigned a rock code.  Ensure that mining cost adjustment factors and processing cost adjustment factors, if used, have reasonable values and that background values are filled with 1, not zero or -99. Required Attributes



First, there must exist an attribute containing a grade value for every block in the model. These values must exist as a fraction of "units" / tonnes, with a zero grade usually denoting an air or waste block. The metal contents produced are then in "units". If an air or waste block has a grade greater than zero, the grade is just ignored as part of the export routine. For a Whittle output, several grade fields are needed, one for each element to process. Second, there must exist an attribute with a rock code in it. This attribute can be either a character or an integer attribute. This rock code is used to determine whether the block is ore, waste, or air. If the block is an ore block, the rock code is used to determine the material name to output to the Whittle .mod file. Whittle rock codes have a maximum of four characters, so if the code in the block model is longer than four characters, then the names are truncated. Make sure that all rock codes used in the block model are unique over the first four characters. If the rock code is numeric, the number will be converted to a zero-padded character string. Therefore, any numeric rock code larger than 9999 is also truncated. All blocks must have a rock code value, otherwise they are assumed to be waste. Air blocks must have a rock code value. The third common field is a specific gravity attribute. This attribute contains the specific gravity for the block. If a block is to become a parcel for the Whittle block and the block is not air, its specific gravity value is used in calculating a weighted average of the specific gravity for the entire Whittle block. There are several attributes which also must exist for some Whittle products but not others. Whittle .mod files require a Mining Cost Adjustment Factor (MCAF). All blocks must contain an MCAF value. However, if all blocks in the model contain the same MCAF, then no attribute is required, the single value can be entered on the export whittle form. Because cost of mining applies only to blocks containing rock, MCAF can be zero for air blocks. See Outputting a Whittle model file for more information on how MCAF is used and calculated in sub-blocked models. A Processing Cost Adjustment Factor (PCAF) must also exist for a Whittle .mod file. Again, however, if the PCAF value is the same for all blocks in the model, no attribute is required, the value can be entered on the Export Whittle form. The cost of processing a block obviously only applies if the block is to be processed, so air and waste blocks do not need a meaningful PCAF value. See Outputting a Whittle model file for more information on how PCAF is used and calculated in subblocked models. If all the above attributes are correctly filled — you can check this graphically using the block model functions — the output Whittle file should be simple to output for all block models except blocks model with attributes filled with Indicator Kriging. Validate for Export to Whittle You should use this function before exporting a block model to Whittle. This function validates a Surpac block model so that you can export it to Whittle (as a .mod file). By validating the block model, you can identify logical errors in the block model (for example air blocks that have a positive grade). The validation step can save you time, and help you avoid potentially costly mistakes later when you are working on the model in Whittle. This function scans every block in the Surpac block model, and tests each one for the conditions specified in the following 'fields on the form' table. If a block fails to meet a condition, the Error lookup attribute of the block is set to "WTLERROR". Any errors are reported only once in the Report file name, because all blocks could contain the same error, and the length of the report would become too long to be usable. Successful tests results are also reported. Prerequisites: The block model must have attributes for sg, rock, and grade of the resource. Air blocks must have a specific value, for the rock attribute, to indicate that they are air. Waste blocks must have a specific value, for the rock attribute, to indicate that they are waste. To run this function: In the Function Chooser, type BM VALIDATE FOR WHITTLE OUTPUT, and press ENTER. If a block model is not already open, you are prompted to open a block model. Fields on the Validate for export to Whittle form Field Description  Selected. The block model is an indicator kriged block model. That is, it does not use a single attribute for grade, but instead it uses multiple attributes for grade, each of which states the probability that the block has a grade within a specific range of values. When you select Indicator Kriged, the Grade Indicator Attribute field is hidden, and therefore the validation does not perform the checks relating to the single Kriged grade attribute.  Cleared. The block model is not an indicator kriged model. The Grade Attribute field is displayed and the validation performs checks relating to the grade attribute. Rock code The attribute that contains an alphanumeric rock code for each block. Rock codes must have at least 1, and no attribute more than 4, characters. An example Rock code attribute is rock. The attribute which contains the specific gravity, that is density, value for each block. The SG attribute must have a SG attribute data type of real, and its value must be 0 or higher. An example SG attribute is sg



The attribute that contains a Mining Cost Adjustment Factor (MCAF) for each block. The MCAF attribute must have a data type of real, and its value must be greater than 0. An example MCAF MCAF attribute is mcaf. attribute Tip: Alternatively, you can type a value, for example 1, to force the validation to use a specific MCAF value for all blocks. The attribute that contains a Processing Cost Adjustment Factor (PCAF) for each block. The PCAF attribute must have a data type of real, and its value must be greater than 0. An example PCAF PCAF attribute is pcaf. attribute Tip: Alternatively, you can type a value, for example 1, to force the validation to use a specific PCAF value for all blocks. The attribute for volume adjustment factor. The Volume adjustment attribute must have a data type of real, and its value must be between 0 and 1. Volume adjustment is optional. You use the Volume adjustment attribute to Volume modify the ore tonnes in a block, but NOT the total block tonnes. Volume adjustment is a factor less than one, for adjustment example 0.8 not 80%. If the block has 100t @ 2 g/t, without the volume adjustment the ore parcel contains 100t @ 2 g/t for 200g. If the volume adjustment was 0.5, then the total block tonnes remain 100t while the parcel contains 50t @ 2 g/t for 100g. Waste rock The rock code that defines "undefined" waste. Only the first 4 characters are used. An example Waste rock code code is WAST. Air rock code The rock code that identifies a block that is air. An example value is AIR. Zone The attribute that contains the rock type number. The Zone attribute must have a data type of integer, and its value attribute must be greater than 0. This field is optional. Grade The attribute, or attributes, that contain the grade for each block. Grade values must be 0 or higher. attribute The block size you intend to use when you export the block model to Whittle. BM VALIDATE FOR WHITTLE OUTPUTS checks whether there will be more than 999 parcels (that is, subExport Block blocks) in any block at the Export Block Size. This check is important because you can have no more than 999 Size parcels in a block in Whittle. Additional sub-blocks would be removed when you export to Whittle, and so you could lose ore.  Selected. Before the validation occurs, the block model is constrained to the constraint you specify. After Constrain you click Apply, the Enter Constraints form is displayed to allow you to specify the constraint. Model  Cleared. No constraint is applied. The attribute that will contain the error code if validation fails. If you type the name of an attribute that does not yet Error lookup exist, you will create the new attribute. attribute Note: BM VALIDATE FOR WHITTLE OUTPUT overwrites any existing values for the Error lookup attribute. Report file The name of the report file to output. The text file contains a report of the successful tests and the failed tests. name Output A report file is created that shows which validation tests passed and which failed. If any validation errors occurred, the blocks where the errors occurred have the Error lookup attribute set to WTLERROR. Tip: To see the error blocks in Graphics, display the block model, and colour by the Error lookup attribute. You might need to apply a constraint to hide less important blocks that are obscuring the view, for example by constraining where the rock attribute does not equal waste. The following image shows the result of running BM VALIDATE FOR WHITTLE OUTPUT on a block model where most validation tests passed but some air blocks do not have an sg value of zero, and some air blocks have a grade value greater than zero. The block model is displayed, and then constrained to hide the waste blocks, and coloured by the Error lookup attribute. The blocks that have an Error lookup attribute value of WTLERROR are displayed in red.



Note: This function also tests whether the Surpac block model has more than 999 999 blocks in any direction.