Other compost equipment providers often approach
compost quality from a "What's not in it?" interpretation
of quality (pathogens, weed seeds, heavy metals, etc.). Attaining
minimum government safety standards is their goal. Beyond this,
because size-reduction is one of the results of composting, they
often measure success by the extent to which they can make an
organic waste stream disappear. Their equipment is therefore designed
to achieve those purposes.
Midwest Bio-Systems,
on the other hand, determines compost quality by:
What are the defining
differences between these approaches relative to turner design?
Drum speeds — Aeromaster
compost turners have variable drum speeds within a low rpm range.
Equipment does not make compost — microbes do!
So high quality composting is simply based on creating the optimal
environment for beneficial microbes to flourish and undesirable
microbes to diminish. High drum speeds retard rather than enhance
the quality composting process as well as limiting humus formation.
Materials need not be propelled against shields (limiting aggregation)
or thrown many feet behind the drum. Safety is also an issue here
as projectiles can be propelled from the windrow with high speeds.
Hourly cost of operation
— clearly affected
by drum speeds is hourly cost of operation and downtime. Aeromaster
turners have proven to cost less than 1/2 the industry standard.
Volumes
—extremely large compost turners can be
used to create a high heat environment for pathogen elimination
and size reduction. But excessively large windrows reduce oxygen
access for the microbes and quality is negatively impacted.
Tine shape and material movement pattern
—an ideal turning environment will lift,
blend, and aerate compost feedstocks. A key evidence of composting
excellence will be O2 and CO2 exchange. What are windrow CO2 levels
prior to turning compared to directly behind the turner? Best
turning and movement patterns will provide new contact points
in the feedstocks for microbial and chemical interaction. Tines
should therefore handle the materials gently, moving perimeter
materials to the center of the row and center materials to the
perimeter. Tines should not cut, shred, or pulverize materials,
especially after the first week in the row.
Watering
—to create an optimal microbial environment,
a turner must be able to apply water evenly throughout the row,
rather than only to the perimeter.
Is Midwest Bio-Systems the only turner builder
which embraces this composting philosophy? No. The key questions
then among turner manufacturers sharing this philosophy are ones
of value, durability, and service. Contact us for this value,
durability, and service information.
