Biofiltration systems utilizing thermophilic (55 degreesC) bacteria were co
nstructed and tested for the removal of methanol and alpha -pinene - two im
portant volatile organic compounds (VOCs) in the forest products industry.
Thermophilic bacterial mixtures that can degrade both methanol and alpha -p
inene were obtained via enrichment techniques. Two bench-scale thermophilic
biofiltration systems (1085 and 1824 cm(3)) were used to examine compound
removals at different residence times, with influent concentrations of 110
ppmv methanol and 15 ppmv alpha -pinene. At a residence time of 10.85 min,
the smaller system had removal efficiencies of > 98% for methanol, but only
23% for alpha -pinene, The larger system was operated with the same parame
ters to evaluate residence time and surfactant effects on compound removals
. At a residence time of 18.24 min, both methanol and alpha -pinene removal
rates were greater than or equal to 95%, However, alpha -pinene removal dr
opped to 26% at a residence time of 6.08 min; methanol removal was not affe
cted. Subsequent addition of a surfactant mixture increased alpha -pinene r
emoval to 94% at the shortest residence time. No residual alpha -pinene was
detected with the support medium Celite R-635, indicating that the surfact
ant may increase mass transfer of alpha -pinene.