Final Report - Ohio Department of Transportation

2010 Rhododendron Leaves 57.36 18.94 73.21
2009 Sycamore Leaves 9.31 37.56 46.54
2009 Willow Leaves 10.59 37.96 58.34
Average 21.26 32.23 59.17
Standard Deviation 18.97 9.56 6.83
Another goal of the project was to investigate if drying yard waste feed stock before
carbonization significantly increased yields of byproducts. A drying step would not be difficult
to implement, but would add additional area and cost requirements to the carbonization process.
The basic concept is that, if yard waste had less moisture to expel, off-products might have
higher organic concentrations, and might favor higher molecular weight products.
Two comparisons between dried and “wet” yard waste are included in Table 5 and are
emphasized in Table 8. In both cases, although the dried samples had a smaller moisture content
and larger organic content than“wet” samples, the collection of byproducts was less efficient
when the yard waste was dried before carbonization. Figure 25 illustrates the relationship
between moisture content and collection efficiency.
Table 8 - Comparison of the Yield from Un-dried and Dried Carbonization Feed Stock
Yard Waste
Moisture Organics
Byproduct
Collection
Year Type Component
Branches
(%) (%) Efficiency (%)
2009 American Elm (dried) 0 62.99 22.2
2009 American Elm Branches 39.12 30.65 74.1
2009 Rhododendron Leaves 9.60 34.23 57.4
2010 Rhododendron Leaves 57.36 18.94 73.2
After applying linear regression analysis, the results of Fig. 25 illustrate that, although there is
a models correlation that seems to favor higher moisture content, the correlation is not sufficient
to conclude that pre-drying is advantageous. If anything, the data indicate that the presence of
more moisture assists in the formation of organic byproducts.
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