DYNAMIC ANALYSIS OF HARVESTING AND HANDLING SYSTEMS FOR BIOMASS ENERGY FEEDSTOCKS
Abstract
A SLAM II combination network discrete event model was developed to simulate harvest and transport of corn residue, hay and wood chips for delivery to a central biomass conversion plant, on a year around basis. Ten years of climatological and biomass production data, from 1971-72 to 1980-81, were included in the model, in order to quantify the effect of weather on system performance. The model was used to analyze the system under several combinations and proportions of three feedstocks, plants of two sizes, localized in three regions: Northern, Central and Southern Indiana. Different harvest systems were compared: corn residue and hay big round bales or stacks, and wood chips from clear cut, thinning or plantation operations. Four storage capacities at the plant yard for corn residue and hay were compared and also the effect of number of machines on equipment utilization and costs were studied. The results showed that weather plays an important role on system performance, especially on the collection and transportation of corn residue and hay. In the worst weather year studied, the conversion plant working time was increased 29% by going farther to collect corn residue, increasing the haul radius by 41%, with the same equipment. To supply a conversion plant utilizing 40,000 Mg/year (1 Mg = 1 metric tonne) of wood chips or less, the forestry equipment should be utilized not only to produce chips for this particular plant, but also to perform other jobs, in order to decrease production costs. Corn residue yields averaged 3.3 Mg/ha and hay yields averaged 1.9 Mg/ha. Wood chips productivity per cutting averaged 86 Mg/ha for clear cut, 53 Mg/ha for thinning and 40 Mg/ha for plantations, for 100, 20 and 5 years rotation ages respectively. In an average weather year it cost up to 71% more to collect and transport corn residue bales than to produce and transport wood chips from clear cut. Stacks and bales cost about the same to produce, but it cost 55% more to transport bales than to transport stacks. Production and transportation costs were about twice as much for a clear cut operation compared to a plantation system.
Degree
Ph.D.
Subject Area
Agricultural engineering
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.