Converting Waste Agricultural Biomass into a Resource - UNEP

mode, all of the steam directed to the turbine is condensed and returned to
the boiler via boiler feedwater pumps. The turbine selected for this application
does have an extractive lobe which allows the extraction of up to 100,000
pounds per hour of medium pressure steam. The extracted steam is piped to
a re-boiler, which generates utility steam for consumption in the adjoining food
processing plant. By incorporating a re-boiler into the design, turbine quality
feedwater is segregated from process plant quality water and avoids the
possible contamination resulting from use in food processing.
The entire system, from the receipt of the rice hulls to the generation of
electricity is controlled by a human machine interface located in a control
room. The control room adjoins the turbine generator building and crew
quarters. From the central CTR’s each function of the overall process can be
individually adjusted, or the overall process can operate in a fully automatic
mode.
Main Products
Electrical Energy and Process Steam
Environmental Considerations
For compliance with particulate matter in vent stacks, the products of
combustion exiting the boiler are filtered of fly ash in a conventional
baghouse. An induced draft fan, which maintains a slight negative pressure
through out the entire process, is located after the baghouse. The induced
draft fan discharges into a vent stack.
Investment and Operating Cost
All fabricated equipment was manufactured in Tulsa by Primenergy’s sister
company, Heater Specialists, L.L.C. and major equipment was pre-assembled
prior to shipment to Arkansas. The project duration from final contact signing
until initial commissioning was less that one calendar year.
Examples of Real Life Applications
Rice Hulls to Electrical Energy & Process Steam
Stuttgart, Arkansas
Supplier:
Primenergy, L.L.C
P O Box 581742 Tulsa Oklahoma 74158
Phone: (918) 835-1011 Fax: (918) 835-1058
Sources:
1. http://www.primenergy.com/Projects_detail_Stuttgart.htm
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