HomeMy WebLinkAboutSP200800032 Legacy Document 2008-09-30example, if stumps are collected that have been pulled from the ground due to clearing
activities these will have dirt and rock embedded and intertwined with the stump roots.
When the stump is placed into the tub grinder and processed, the dirt and rock will be
sifted out using screens and collected into separate piles from the wood.
From here, the processed wood biofuel will
be organized into long, low mounds
commonly known as windrow composting
(see the image to the right). These mounds
will be no more than 12' tall, checked
regularly and turned every few days to
maintain a proper temperature (ranging
from 55 to 80°C) and moisture content
(ranging from 0 to 17%). This windrow
process is similar to techniques commonly
used in large-scale farm/composting
(2)
transformation facilities. Windrow
composting (or the turning
method) allows for better porosity
and oxygen content to the
microbes digesting the organics,
mixing or removing moisture, and
redistributing cooler and hotter
portions of the pile in order to
reduce spontaneous combustion,
as well eliminating any gaseous
waste from harmful bacteria.
Equipment typically used in this
step includes front-end loaders
and/or mulch turners.
Following this handling process is
the next step of aging. This step varies depending on the demand of the consumers. Wood
biof iel can be handled differently in several phases. Obviously, the process described
above is the first few steps in creating any biofuel by-product. From there, depending on
the coarseness (i.e. end -product) desired, sometimes the by-product doesn't need to sit or
breakdown as long and can be handled sooner. This creates a coarser material. The longer
it sits, or is processed again, the finer the material becomes.
Central Virginia Recycling
SP -2008-00032
Certified Engineer's Report
4