Rotary drying of wood waste fuels with boiler exhaust gases: simulation, field studies, economics

Journal Article · · For. Prod. J.; (United States)

OSTI ID:6616946

Kirk, R W; Wilson, J B

Two computer simulation models of a boiler/dryer system fueled by wood waste were developed, each general enough to be used for different boiler/dryer configurations and to predict boiler performance expected after rotary dryer installation. Model accuracy was tested by comparing predictions with field data from three different boiler/dryer systems currently in operation in the forest products industry. In each case, the models predicted fuel consumption within, on the average, 2 percent of the observed value. The simulation models were then used to examine the effects of various operating parameters - on boiler performance. On the basis of these studies, the rotary dryer is expected to reduce fuel consumption and decrease the boiler's sensitivity to fluctuations in fuel moisture content (MC), excess air after combustion, and boiler exhaust temperature. An economic analysis of retrofitting a rotary dryer to a boiler operating at moderate conditions indicated cash-flow payback periods based on hogged fuel savings to be 3.6 years for a used dryer and 5.2 years for a new dryer. The analysis assumes that the fuel was dried from 50 to 30 percent MC, wet basis. Payback periods based on Btu-equivalent savings of natural gas and No. 6 heating oil were estimated to be, respectively, 1.2 and 1.3 years for a used dryer and 2.1 and 2.2 years for a new dryer.

• Research Organization: Oregon State Univ., Corvallis
• OSTI ID: 6616946
• Journal Information: For. Prod. J.; (United States), Journal Name: For. Prod. J.; (United States) Vol. 36:7-8; ISSN FPJOA
• Country of Publication: United States
• Language: Finnish

Related Subjects

09 BIOMASS FUELS
090400* -- Solid Waste & Wood Fuels-- (-1989)
140504 -- Solar Energy Conversion-- Biomass Production & Conversion-- (-1989)
APPLIANCES
BOILERS
CHEMICAL REACTIONS
COMBUSTION
COMPUTERIZED SIMULATION
DRYERS
DRYING
ECONOMIC ANALYSIS
ECONOMICS
ENERGY CONSUMPTION
FUEL CONSUMPTION
INDUSTRY
MOISTURE
OXIDATION
PARAMETRIC ANALYSIS
PERFORMANCE
RETROFITTING
SIMULATION
SOLID WASTES
THERMOCHEMICAL PROCESSES
WASTE HEAT UTILIZATION
WASTE PRODUCT UTILIZATION
WASTES
WOOD BURNING APPLIANCES
WOOD PRODUCTS INDUSTRY
WOOD WASTES