|SUBHASHREE, SRINIVASAGAN - North Dakota State University|
|IGATHINATHANE, CANNAYEN - North Dakota State University|
Submitted to: Biomass and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/27/2020
Publication Date: 12/7/2020
Publication URL: https://handle.nal.usda.gov/10113/7200690
Citation: Subhashree, S.N., Igathinathane, C., Liebig, M.A., Halvorson, J.J., Archer, D.W., Hendrickson, J.R., Kronberg, S.L. 2020. Biomass bales infield aggregation logistics energy for tractors and automatic bale pickers—a simulation study. Biomass and Bioenergy. 144:105915. https://doi.org/10.1016/j.biombioe.2020.105915.
Interpretive Summary: Demands for agricultural biomass are ever increasing due to its versatility. Unfortunately, costs associated with harvesting logistics are a major barrier to biomass utilization. An ‘automatic bale picker’ (ABP), which collects and transports bales in a single trip, may improve efficiency of infield biomass bale logistics. A mathematical simulation was conducted to mimic bale collection processes using an ABP and traditional tractor bale harvesting methods. Across a range of field sizes (20 to 640 acres), the ABP was able to decrease the distance traveled by 67 to 83% when compared to traditional tractor bale harvesting methods. Simulations suggested an ABP, with a capacity of 8 bales per trip, was most efficient in improving infield logistics, minimizing collection time, and mitigating soil compaction. Among four field outlet locations for biomass consolidation (origin, field middle, mid-width, and mid-length), the field middle was associated with the least bale aggregation logistic distance for both the ABP and tractor. Simulated outcomes will serve to guide future economic analyses for identification of cost effective approaches to biomass harvest by ABPs.
Technical Abstract: The infield logistics of baled biomass aggregation and transportation to a field outlet is an elaborate operation comparable to crop harvest. Efficient infield logistics are essential for clearing the field for subsequent crops, and for avoiding biomass quality or nutritive value changes, spontaneous heating, and dry matter loss. Traditionally, tractors and trailers are the common and simplest equipment used for infield bale aggregation; however, the modern automatic bale picker (ABP) combines bale picking, accumulation, and transportation to a pre-defined outlet. The efficiency of ABPs, relative to traditional biomass aggregation methods has not been thoroughly evaluated. Several aggregation logistic scenarios using a tractor handling one and two bales/trip (control method) and an ABP handling 8 to 23 bales/trip were studied with field areas ranging from 8 to 259 ha and four outlet locations using a user-developed simulation program in 'R’ language. Circular turning paths of the equipment were accounted for more realistic evaluation of logistic distances. A decrease in logistics distance for the ABP (8–259 ha) with 8 bales/trip was on average 82.90(0.01)% and 66.91(0.01)% compared to that of the tractor with 1 and 2 bales/trip, respectively, showing the effectiveness of ABP over the tractor. The field middle outlet produced the least aggregation distance (44(0.02)% of origin) followed by the mid-edge (30(0.01)% of origin) while the origin outlet produced the most for the equipment. The ABP with capacity of 8 bales/trip produced the least operating time for the field areas (8–259 ha), 5 and 2.6 times lesser than the tractor with capacity of 1 and 2 bales/trip, respectively. Based on relative weights, the most influential variables for predicting the logistics distances were the field area (64.90%) and bales/trip (32.03%). Specific bales/trip logistics distance prediction models based on field area following the power model; and combined multi-variate prediction models for logistics distance and operation time, based on both field area and bales/trip, following the modified Henderson model produced good performance (R2= 0.98). Overall, an ABP with a capacity of 8 bales/trip, which can also handle 11 bales/trip, is recommended considering its smaller physical footprint and decreased impact pressure on the soil compared to higher capacity ABPs. Future work should concentrate on other parameters influencing the logistics, bale stacks on the field and at the edge of the field, and economic analysis of the infield logistics using ABP.