Internal Report Comparison of Grind to Ground vs. Grind to Stu Spencer, RPF Keywords Comminution, horizontal, cost, productivity, grind to ground, grind to truck Abstract FPInnovations-Feric Division (Feric) monitored a wheeled horizontal as it comminuted immature mountain pine beetle killed lodgepole pine stands in the southern interior of British Columbia. The study determined the cost effectiveness of grinding hog fuel directly into trucks versus grinding hog fuel into piles for subsequent re-loading. Advantages and disadvantages of both strategies are discussed. Introduction The productivity of conventional roadside comminuting operations depends on the mechanical availability of the equipment, the productivity of the and comminution equipment, and the availability of trucks under the outfeed conveyor. For most operations, loading comminuted material directly into trucks is most efficient. However, when trucks are delayed comminution equipment remains idle waiting for them to arrive. This reduces comminution equipment utilization and production, and ultimately increases costs. An alternative strategy is to separate comminution and transportation by creating piles of comminuted material. These piles can be loaded into trucks independent of the comminution equipment by an additional. This project was established to determine the advantages and disadvantages of a grind-to-ground strategy. Page 1 of 11
FPInnovations studied a Bandit Beast 3680 wheeled horizontal comminuting (grinding) immature mountain pine beetle killed lodgepole pine in British Columbia s southern interior during the winter of 2008-2009. The objectives were to: Determine whether truck load size increased when loaded from piles compared to directly loaded from the. Determine the additional costs to load feedstock from the ground and determine if these costs are offset by increased load size and reduced cycle time. Evaluate the added flexibility provided by having surge piles to load from during grinding equipment delays. The study was conducted in cooperation with Jaeden Resources and Trace Resources and was funded by Natural Resource Canada s Transformative Technologies program, BC Ministry of Environment s Woody Debris Management Program, and a contribution from the British Columbia Ministry of Forests and Range. Acknowledgments The author would like to thank Ron Racine of Trace Resources and Dan Eaton of Jaeden Resources for allowing access to their operations. Marv Fraser of Jaeden Resources was invaluable in assisting the author in day to day operations. Site and equipment description The study was conducted from December 2008 to February 2009 at a series of small cutblocks approximately 40 km south of Kamloops, British Columbia 1. The site consisted of standing, immature lodgepole pine that was two thirds dead. Trees were felled and skidded to landings where they were decked in preparation for grinding. Equipment included a 700 HP 3680 Bandit Beast horizontal and a John Deere 2154 log with a full-rotation IMAC HX40 grapple attachment. The operator controlled the via radio remote control. A Volvo 240EC excavator with bucket attachment also loaded trucks. 1 More details on the site can be found in Spencer, 2009, Comminuting Immature Mountain Pine Beetle Killed Lodgepole Pine Stands Page 2 of 11
Highway B-train chip vans hauled most of the feedstock to Domtar Pulp and Paper Inc. s pulp mill in Kamloops. The remainder was hauled by 53 ft walking-floor trailers to various greenhouses in Aldergrove and Delta, BC. Feedstock was ground into three size classes: 5 cm, 7.5 cm and 10 cm. Methods The and were equipped with MultiDat data loggers to record their power-on, motion and delay times. Each truck load was weighed at a government scale on route to its destination, and load slips recorded where the load originated, the gross, tare and net weights. Green net loads were converted to oven dry units (tonnes) using moisture contents determined by Domtar s technical department. Results Grinding and loading operations The produced 4694 Odt of hog fuel in three size classes during the study (Table 1). Approximately 56% of the stand was ground directly into trailers; 141 B-train trailer loads delivered to Kamloops and 59 53-ft walking floor trailer loads delivered to greenhouses around Vancouver. The remaining 44% was ground into piles. Approximately 77% of the stand was ground into B-train trailers (141 loads). The remaining 23% was ground into 53 ft walking floor trailers (59 loads) and transported to greenhouses on the coast (Table 1). Page 3 of 11
Table 1. Hog fuel produced by size class Hog Fuel Size (cm) Direct to truck Grind-to-ground Amount Produced No. of Loads (Odt) No. of loads (Odt) (Odt) Super B 53-ft Super B 53-ft Super B 53-ft Super B 53-ft 5cm 9 4 227 76 0 12 0 220 523 7.5cm 20 11 517 203 8 3 201 55 976 10cm 60 6 1 517 106 44 23 1 153 419 3195 Total 89 21 2 261 385 52 38 1 354 694 4 694 Table 2. Percentage of total weight by trailer type and load method type Load Total weight Weight (Odt) method (%) Super B Direct 2 261 48 Super B Pile 1 354 29 Total Super B 3 615 77 53-ft walking floor Direct 385 8 53-ft walking floor Pile 694 15 Total 53-ft walking floor 1 079 23 Total 4 694 Difference in load size by loading method varied from a 3.5% increase to a 4.4% decrease. No trend was visible from load data (Table 3). Table 3. Cost/benefit in load weight by loading from pile Cost/benefit in load type Hog fuel Size (cm) weight by loading from pile Super B 5 N/A Super B 7.5-2.7% Super B 10 3.5% 53 Ft Walking 5-4.4% 53 Ft Walking 7.5-0.5% 53 Ft Walking 10 2.8% Machine costs were generated using FPInnovations standard costing methods that include direct owing and operational costs, but exclude overhead items such as supervision, crew transportation, room and board, mobilization, and demobilization, and profit risk. Components of the individual machine cost estimates are shown in Appendix 1 and the summary of all estimated costs for delivering the biomass from the cutblock to the power plant are shown in Appendix 2. Page 4 of 11
Using FPInnovation s hourly costs, the delivered costs of biomass for three scenarios: 100% direct to trailer grinding, 100% load from pile and 56% load direct to trailer and 44% load from pile (Table 4) were calculated. Scenario 1 This scenario assumes that 100% of the feedstock will be ground directly into trailers. The s sole responsibility would be to place material into the. Scheduled time for the and would be equal. Cost for this scenario was $52.22/Odt. Scenario 2 This scenario describes what happened during the actual study. 56% of the feedstock was ground directly into trailers and 44% ground into piles. The was responsible for placing material into the and loading trucks from the ground piles. An excavator was also used for a short time to load feedstock from the piles. Cost for this scenario was $54.59/Odt. Scenario 3 This scenario assumes that 100% of the feedstock would be ground into piles and later loaded into trailers. The would be responsible for placing feedstock into the and later loading into trucks after grinding was finished. Cost for this scenario was $56.95/Odt. A hypothetical analysis was also undertaken using the assumption that all of the trailers in the study were Super B-Train trailers and the hog fuel was transported to Kamloops. This hypothetical analysis was undertaken so that results could be compared to an earlier study involving the grinding of roadside logging residue at a nearby block (Spencer, 2009) Table 4. Comparison of estimated costs for comminuting, loading and trucking hog fuel Cost per Odt (80% Super B ) Cost per Odt (100% Super B ) Scenario 1 (100% direct load) $52.22 $43.02 Scenario 2 (56% direct load, 44% load From pile) $54.59 $45.96 Scenario 3 (100% load from pile) $56.95 $48.08 Page 5 of 11
Discussion There was no consistent increase in load size when loading from a pile versus loading directly from the. The drivers moved the trailers during direct loading, allowing for a consistent load throughout the trailer. In comparison, when loading from piles, the operator smoothed out the load with the grapple or bucket, creating a consistent load throughout the trailer. Attempts to press down on the feedstock by the grapple attachment were unsuccessful in creating room for additional hog fuel. There was benefit in creating surge piles because it improved the operation s flexibility although the additional cost incurred by loading feedstock from piles could not be offset by increased load size. The piled material allowed the operator to load the size of hog fuel required without the need to change the sorting screen on the. The piled hog fuel also allowed the operation to continue even when the was in need of repairs. Scenario 1 incurred the least costs and would be effective in an operation where only one size of hog fuel was needed. Scenario 2 would be effective when some flexibility was necessary due to customer demand for different sized hog fuel or when truck availability was marginal. Scenario 3 would be effective when trucks are not immediately available, when the s time is limited to a specific area, or multiple hog fuel sizes are required. Conclusions FPInnovations conducted a study of a Bandit Beast 3680 wheeled horizontal comminuting hog fuel in a mountain pine beetle killed lodgepole pine stand in British Columbia s southern interior in the winter of 2008-2009. No increase in load size was recorded when loading hog fuel into trailers from piles on the ground. The additional cost for loading from a pile versus loading directly into trailers was $4.73 Odt. This additional cost allowed for flexibility when dealing with customer demand for different sized hog fuel. Bibliography Spencer, S., 2009, Hog Fuel from Roadside Residue in Beetle Killed Lodgepole Pine Stands. FPInnovations, FERIC Division. Page 6 of 11
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Appendix 1 Grinding Item Make and model Bandit Beast 3680 John Deere 2154 Volvo 249EC Excavator Scheduled hours per year 2160 2160 1800 Utilization rate (%) 48 59 50 Total purchase price ($) 500 000 400 000 250 000 Expected life (h) 8 000 9 000 9000 Residual value, % of purchase (%) 20% 20% 20% Labour wages ($/h) 0 28.00 28.00 Wage benefit loading (%) - 35% 35% Fuel consumption per PMH (l/h) 100.0 20.0 35.0 Fuel cost ($/l) 1.00 1.00 1.00 Lube and oil as % of fuel (%) 10% 10% 10% Repair and maintenance ($/h) 50.00 15.00 15.00 Annual repair and maintenance ($) 30 000 10 000 10 000 Licences and inspection ($) Radio and communication ($) 2 000 2 000 Grinder screen (h) 2160 Grinder screen ($) 3 500 Tires, chains, undercarriage life (h) 5 000 5 000 5000 Tires, chains, undercarriage cost ($) 25 000 25 000 20000 Major rebuild life (h) 5 000 5 000 5000 Major rebuild cost ($} 70 000 40 000 30000 Other periodic cost life (h) 2160 Other periodic cost ($) 36 000 Owning cost ($/h) 65.28 47.78 31.39 Operating cost ($/h) 127.98 90.33 85.00 Total $/h 193.25 138.10 116.39 Page 8 of 11
ing Item Make and model Super B-Train chip truck Super B- Train trailer Tandem Axle 53ft Tridem Trailer Scheduled hours per year 2160 2160 1998 1998 Utilization rate (%) 75 75 75 75 Total purchase price ($) 128 000 140 000 128 000 100 000 Expected life (h) 5940 11 880 14 000 14 000 Residual value, % of purchase (%) 35% 24% 35% 24% Labour wages ($/h) 23.00 0 23.00 Wage benefit loading (%) 35% - 35% Fuel consumption per PMH (l/h) 32.4 0.0 32.4 Fuel cost ($/l) 1.00 1.00 Lube and oil as % of fuel (%) 15% 0% 10% 0% Repair and maintenance ($/h) 9.00 3.00 9.00 3.00 Annual repair and maintenance ($) 10 000 14 000 10 000 5000 Licences and inspection ($) 3000 2000 3000 500 Radio and communication ($) 2 000 2 000 Rigging life (h) Rigging cost ($) Tires, chains, undercarriage life (h) 2160 2160 1980 1980 Tires, chains, undercarriage cost ($) 9 000 14 000 9 000 7500 Major rebuild life (h) Major rebuild cost ($} Other periodic cost life (h) Other periodic cost ($) Owning cost ($/h) 18.48 13.77 10.70 8.86 Operating cost ($/h) 82.41 17.33 81.76 7.50 Total $/h 100.89 31.10 92.46 16.36 Page 9 of 11
Appendix 2 Bandit Beast 3680 John Deere 2154 Super B Chip Tandem Axle 53ft Walking Floor Tridem Trailer 100% Direct 80% Super B, 20% 53Ft ($/SMH) 193.25 138.10 100.89 31.10 92.46 16.36 SMH 384 384 456 456 530 530 Machine Cost ($) 74208 53030 46006 14182 49004 8671 Portion of Total Cost (%) 30% 21% 19% 6% 20% 4% Total Cost ($) 245101 Delivered Cost ($/Odt) $52.22 Bandit Beast 3680 John Deere 2154 Volvo EC240 Excavator Super B Chip Tandem Axle 53ft Walking Floor Tridem Trailer 56% Direct, 44% Reload - 80% Super B, 20% 53Ft ($/SMH) 193.25 138.10 116.39 100.89 31.10 92.46 16.36 SMH 384 425 70 456 456 530 530 Machine Cost ($) 74208 58693 8147 46006 14182 49004 8671 Portion of Total Cost (%) 29% 23% 3% 18% 5% 19% 3% Total Cost ($) 258911 Delivered Cost ($/Odt) 54.59 Bandit Beast 3680 John Deere 2154 Super B Chip Tandem Axle 53ft Walking Floor Tridem Trailer 100% Reload 80% Super B, 20% 53ft ($/SMH) 193.25 138.10 100.89 31.10 92.46 16.36 SMH 384 545 456 456 530 530 Machine Cost ($) 74208 75265 46006 14182 49004 8671 Portion of Total Cost (%) 28% 28% 17% 6% 18% 3% Total Cost ($) 267336 Delivered Cost ($/Odt) 56.95 Page 10 of 11
58% Direct, 42% Reload 100% B - Trains Bandit Beast 3680 John Deere 2154 Volvo EC240 Excavator Super B Chip ($/SMH) 193.25 138.10 116.39 100.89 31.1 SMH 384 425 70.00 566 566 Machine Cost ($) 74208 58693 8147 57104 17603 Portion of Total Cost (%) 34% 27% 4% 27% 8% Total Cost ($) 215755 Delivered Cost ($/Odt) 45.96 100% Direct 100% B -Trains Bandit Beast 3680 John Deere 2154 ($/SMH) 193.25 138.10 100.89 31.1 SMH 384 384 566 566 Machine Cost ($) 74208 53030 57104 17603 Portion of Total Cost (%) 33% 26% 28% 14% Total Cost ($) 201945 Delivered Cost ($/Odt) 43.02 100% Reload 100 % B -Trains Bandit Beast 3680 John Deere 2154 ($/SMH) 193.25 138.10 100.89 31.1 SMH 384 556 566 566 Machine Cost ($) 74208 76784 57104 17603 Portion of Total Cost (%) 26% 41% 22% 11% Total Cost ($) 225699 Delivered Cost ($/Odt) 48.08 Page 11 of 11