Biomass baling

A different concept in biomass baling has appeared in recent years. This is the "bulk" or "round" baler which operates as a windrow wrapper rather than a compactor. This implement produces large cylindrical bales weighing up to 1500 pounds each (68,69). Since no appreciable compaction is involved, the bale density is relatively low, on the order of 10 to 12 pounds per cubic foot. More recent modifications enable this machine to produce cube-shaped bales which are more economical of space during transport and storage. Both front- and rear-end loaders suitable for handling these bales are marketed as conventional tractor attachments (65). 

Agricultural crop residues are a valuable renewable biomass resource. In 1999, American farmers harvested 53,909,000 acres of wheat (1). The straw from this acreage of wheat represents >50 million t annually. Currently, some of the straw is harvested (baled) for use as livestock bedding or low-grade animal feed. However, these low-value uses provide only a... 

Briquetting of biomass can be achieved by different techniques, and by either using some kind of binder or by direct compacting without any binder. One example from a pilot plant is presented below. Bales of raw material are put on a conveyor, transported to a shredder and stored in a silo. The shredder cuts the material into particles ranging from microscopic to 15 mm. When the production of briquettes starts, material from the silos is transported through a mixer and a... 

Herbaceous biomass that has been solar-dried and baled can be transported to processing or storage sites without appreciable difficulty with existing equipment. However, this can entail a significant cost. Ordinarily such materials would be loaded directly in the field on a low-bed truck. Standard bales (60-80 pounds) can be loaded manually or with mechanical loaders requiring only one laborer on the truck for final positioning of the bales. Bulk bales would be stacked two layers deep on the truck bed with tractor-mounted loaders. The same truck would transport the biomass to a final... 

Grate firing system for herbaceous biomass 50 kW-20 MW Bales, chipped herbaceous biomass... 

FIGURES Example of a cigar burner for straw bales. [From Kaltschmitt, M., and Hartmann, H., eds. (2001). Energy from Biomass, Springer, Beriin, Heidelberg, Germany. (In German.)]... 

FIGURE 2.9 Midwest com stover harvested in 2009 exceeded moisture limits for stable bale storage, while in 2010 nearly aU harvested biomass could be stored stable in conventional stacks. 

Darr Ml, Shah AJ. (2012). Biomass storage An update on industrial solutions for baled biomass feedstocks. Biofuels, 3, 321-332. 

Smith WA, Bonner IJ, Kenney KL, Wendt LM. (2013). Practical considerations of moisture in baled biomass feedstocks. Biofuels, 4, 95-110. 

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