title: Drying characteristics and equilibrium moisture content of steam-treated Douglas fir (Pseudotsuga menziesii L.).
abstract: Douglas fir (Pseudotsuga menziesii L.) particles were exposed to high pressure saturated steam (200 and 220 °C for 5 and 10 min) to improve the durability and hydrophobicity of pellets produced from them. Depending on treatment severity, the moisture content of the particles increased from 10% to 36% (wet basis). Douglas fir particles steam-treated at 220 °C for 10 min had the fastest drying rate of 0.014 min(-1). The equilibrium moisture content (EMC) of steam-treated samples decreased with increasing steam temperature and treatment time. The Giggnheim-Anderson-deBoer (GAB) equilibrium model gave a good fit with the equilibrium data with R(2) = 0.99. The adsorption rate of untreated pellets exposed to humid air (30 °C, 90% RH) for 72 h was 0.0152 min(-1) while that of steam-treated pellets ranged from 0.0125 to 0.0135 min(-1) without a clear trend with steam treatment severity. These findings are critical to develop durable and less hygroscopic pellets.
authors.affiliation: Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC, Canada V6T 1Z3.
authors.forename: Pak Sui
authors.initials: PS
authors.lastname: Lam
authors.forename: Shahab
authors.initials: S
authors.lastname: Sokhansanj
authors.forename: Xiaotao T
authors.initials: XT
authors.lastname: Bi
authors.forename: C Jim
authors.initials: CJ
authors.lastname: Lim
authors.forename: Sylvia H
authors.initials: SH
authors.lastname: Larsson
mesh_terms: D000327:Adsorption; D003890:Desiccation / Q000379:methods*; D006813:Humidity; D007700:Kinetics; D010316:Particle Size; D011312:Pressure; D028224:Pseudotsuga / Q000737:chemistry*; D013227:Steam; D013696:Temperature; D013997:Time Factors
chemical_list: D013227:Steam