Drying the biomass would help to improve its
heating value and performance but traditional thermal drying technologies
(rotary dryers, fluidized bed, steam, paddle, etc) use fossil fuels, are
energy intensive and expensive to build and operate, require pollution
control systems, are prone to fires and are often difficult to site and
permit (combustion process, emissions, natural gas piping, etc).
In
comparison, a
biological dryer (Biodryer®)
is designed to take advantage of nature's biological oxidation process to
cost effectively reduce moisture content of the organic wastes and resulting
biomass fuel to less than 20%; without the need for natural gas, oil or
steam heating and with minimal capital, labor, maintenance and operating
costs.
Typically,
Wright's biomass product will have a heating value of about 14,000 kJ/kg to
20,000 kJ/kg; depending on the organic feedstock and the desired moisture
content of the fuel (bomb calorimeter, ultimate or proximate analysis, etc).
The
Biodryer®
standard product has the appearance of a mulch or "hog fuel", but it can
also be densified (pellets, briquettes, etc) to meet the specific
transportation, handling and feed requirements of the client.
Mulch ("hog fuel")
Pellets
Briquettes
This
biomass fuel can be used in direct combustion, gasification, cofiring or
calcination energy conversion processes to produce heat, steam or power
while reducing operating costs and emissions.
Biomass is a renewable energy resource
and is often defined as "the
biodegradable fraction of products, waste and residues from
agriculture (including vegetal and animal substances), forestry and related
industries, as well as the biodegradable fraction of industrial and
municipal waste" (source EU Directive 2001/77/EC, Article 2). Biomass
differs from MSW (Municipal Solid Waste) or RDF (Refuse Derived Fuel) in
that it does not contain plastics, textiles, rubbers, contaminates or
non-organic matter which can lead to dioxins, furans and other harmful
emissions. In fact, plastics, textiles, metals and other non-organic
materials should be recycled where possible.
Biomass is also
considered carbon neutral and contains little to no sulphur, mercury and
other pollutants (unlike coal and other fuels). Therefore biomass can also
generate valuable credits (renewable energy, CO2, environmental,
GHG, "Green", etc) for the client.
Unfortunately,
the moisture content of biomass has a great impact on its effectiveness as a
fuel source. Most readily available biomass sources will have a moisture
content of 40% to 90% MC. Considerable energy must be consumed (2444
kJ/kg) just to evaporate this water without doing any useful work in the
process. In addition, the amount of water in the biomass also increases
transportation and handling costs. Therefore, drier biomass has a greater
heating value, burns hotter, more vigorously and more efficiently.
