Reliability-Based Capacity Determination Model for Semi-Mobile In-Pit Crushing & Conveying Systems Bulk Material Handling: New Technology in BMH

Transcription

1 Reliability-Based Capacity Determination Model for Semi-Mobile In-Pit Crushing & Conveying Systems Bulk Material Handling: New Technology in BMH Dr. Robert Ritter

2 Agenda 1 Introduction Context Problem & Objective 2 Random Behaviour of System Elements Operational Disturbance 3 System Capacity Model Hourly Loader Capacity Effective Operating Time 4 Case Study Mine Results 5 Summary 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 2

3 Context Mine Planning Context Main Process: Material Transport Predominate TRUCKS Overall Operational Cost Increase Material Transport Cost Increase 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 3

4 Context More Material On Longer Distances Declining Ore Grades Lead 7% to 3.5% within 30 years Increasing Stripping Ratios Gold 1:1 to 1:3 within 30 years Increasing Mineralisation Depth Belt Conveyors At Increased Cost Increasing Labour Cost Australia increase of about 40% within 10 year Governmental Cost Burdens Canada (BC) Carbon Tax 30$/tonne Requires Crushing In-Pit Crushing and Conveying Systems 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 4

5 In-Pit Crushing and Conveying System Discontinuous Part Continuous Part 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 5

6 Semi-Mobile In-Pit Crushing and Conveying System (SMIPCC) Loading Intermitted Truck Haulage Crushing Conveying Discharge Discontinuous Part Continuous Part 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 6

7 Problem Statement IPCC Systems not a Novelty Some failed to live up to Capacity & Cost Expectations Unsuitable Methods neglect Variance Disturbances 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 7

8 Objective Loading Intermitted Truck Haulage Objective Discontinuous Part 2017 SME Annual Conference and Expo, 20 th February 2017, Denver Develop a structured method to estimate SMIPCC systems capacity under consideration of the random behaviour of system elements Crushing Conveying Discharge Continuous Part 8

9 Random Behaviour of System Elements Fluctuation of operational process time Random variables Described by PDF Distribution: Normal (13.8, 1.5) Statistic Analysis based on Time studies Data sets 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 9

10 Random Behaviour of System Elements - Results Random behaviour of system elements Operational Disturbance Bucket Cycle Time Gamma Repair Time Exponential Bucket Payload Normal Work Time Exponential Truck Payload,, Repair Ratio Truck Loading Time Truck Travel Time,, Normal non dimensional parameter Measure of disturbance frequency 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 10

11 SMIPCC System Capacity Model Hourly Loader Capacity Annual System Capacity Effective Operating Time - Loader 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 11

12 Hourly Loader Capacity Mean Truck Payload Hourly Loader Capacity Truck Loading Time Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 12

13 Hourly Loader Capacity - Deterministic Approach Example: Bucket Payload Bucket Cycle Time Maximum Payload of Truck SME Annual Conference and Expo, 20 th February 2017, Denver 13

14 Hourly Loader Capacity - Stochastic Approach ~ 50, 10.. =139t =71s SME Annual Conference and Expo, 20 th February 2017, Denver 14

15 Hourly Loader Capacity - Deterministic Approach Stochastic Approach , /, / Δ / 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 15

16 Effective Operating Time Time Usage Model Structures time quantities Establishes logical relations Simulation Model for Stochastic simulation model Written in VBA system delay ratio repair ratio 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 16

17 Case Study Based on a Clermont coal mine SMIPCC system setup: P&H4100 Komatsu 930 Crusher Station 6 Conveyor flights Spreader Appropriate input values, / 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 17

18 Case Study - Analyses Analysis 1 Various truck quantities Analysis 2 Economic analysis Analysis 3 Sensitivity analysis Analysis 4 Stockpile Analysis 5 Comparison Results as Diminishing marginal returns Limit at 41.5 Mt ζ as ζ as 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 18

19 Case Study - Analyses Analysis 1 Various truck quantities Analysis 2 Economic analysis Analysis 3 Sensitivity analysis Analysis 4 Stockpile Analysis 5 Comparison Results Cost per tonne approach a 6 Trucks With 0.69 $/t At about 37Mt/a 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 19

20 Case Study - Analyses Analysis 1 Various truck quantities Analysis 2 Economic analysis Analysis 3 Sensitivity analysis Analysis 4 Stockpile Analysis 5 Comparison (continuous part) Results Linear relation between and MRT as MRT -30% MRT IPCC +11% 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 20

21 Case Study - Analyses Analysis 1 Various truck quantities Analysis 2 Economic analysis Analysis 3 Sensitivity analysis Analysis 4 Stockpile Analysis 5 Comparison Δ. / Results as by Diminishing marginal returns Cost reduction to base case -4.6c/t 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 21

22 Case Study - Analyses Analysis 1 Various truck quantities Analysis 2 Economic analysis Analysis 3 Sensitivity analysis Assumption Truck travel time increased by 2.5 Results & Δ.. $/ Analysis 4 Stockpile Analysis 5 Comparison 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 22

23 Summary 1. Quantification of disturbance parameters 2. Development of a stochastic hourly loader capacity method 3. Structured Time Usage Model specific to IPCC 4. Stochastic simulation model for system delay ratio 5. Descriptive conclusions to lay out new SMIPCC systems 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 23

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25 Clermont Coal Mine Transitions: Start of operation: FMIPCC to SMIPCC (inpit) rightafter start 2. SMIPCC (inpit) to SMIPCC (expit) Mar Stop of operation Oct Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 25

26 Clermont Operating Delay System Induced Operating Delay

27 Clermont Coal Mine Crusher Station Spreader Old Crusher Station Location Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 27

28 Clermont Unplanned Downtime Breakdown

29 Clermont Unplanned Downtime Breakdown

30 Clermont Unplanned Downtime Breakdown

31 Clermont Unplanned Downtime Breakdown

32 Clermont Technological Downtime

33 Methodology Description of random behaviour of system elements System Capacity Determination Model Case Study Operational Disturbance Hourly Loader Capacity Time Usage Model Simulation Model Literature Review & Site Data Analysis 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 33

34 Critical Discussion of Results 1. Work Time Distribution 2. Alteration of Truck Allocation 3. Preventative Maintenance for Trucks 4. Trucks in Reserve 5. Increasing Truck Travel Times 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 34

35 10/10/20 Truck Loading Policy No more than 10% of payloads may exceed 1.1 times the target payload and no single payload shall ever exceed 1.2 times the target payload 35

36 Random Disturbance Behaviour of System Elements 36

37 Simulation Model Goal system delay ratio ζ VBA in Excel Simulation Model Description Initialization Disturbance Check Truck Loop Loader Queue Procedure Loading Procedure Travel Procedure Crusher Queue Procedure Truck Discharge Procedure 37

38 Number of Bucket Cycles - Formular

39 Truck Payload Equations I Based on the above it is now possible to describe the distribution function of the truck payload. It is clear that. can be expressed as Where is the distribution function under the condition that passes are handled and under the consideration of the truck payload policy. Using, 1,, 1 (Fehler! Kein Text mit angegebener Formatvorlage im Dokument.-1) 39

40 Truck Payload Equations II It can be seen that, ;, ;, ;, 1. 40

41 Truck Payload Equations III Practically, the sum of only extends over a few (usually between 2 and 7 bucket cycles). In particular, for a sufficiently large. Therefore, the probability density function of can be derived as the following holds ;, (Fehler! Kein Text mit angegebener Formatvorlage im Dokument.-1) Thus the mean and variance of can be written as ;, octoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 41

42 Crusher Type Overview 42

43 Crusher Type Overview 43

44 Crusher Type Properties 44

45 Change of Crusher Types over Decades 45

46 Feed System 46

47 Background Challenges Material transport as the main process in mining Today s predominate mean of material transport - TRUCKS However OPEX Development Mining OPEX Truck Breakdown Evolution Source: SNL Metals and Mining s Strategies for Gold Reserve Replacement After Bozorgebrahimi, 2004 Buhl, 2000 Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 47

48 Increase of Mineralisation Depth Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 48

49 Increasing Stripping Ratios Mudd, 2009 Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 49

50 Declining Ore Grades Mudd, 2009 Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 50

51 Increasing Labour Cost Source: Australian Bureau of Statistics, 2012 Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 51

52 Single Side Loading Doctoral Thesis Defence by Robert Ritter, 1st November 2016, Freiberg 52

53 Recommendation for further Research 1. Incorporation of the aspects highlighted in the critical discussion 2. Extension of method for heterogeneous truck fleet 3. Extension of method for entire IPCC range 4. Inclusion of multiple periods and Investment cost 2017 SME Annual Conference and Expo, 20 th February 2017, Denver 53