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Biofiltration of polluted gas stream containing malodorous
trimethylamine (TMA) was studied in this work. The experiments
were structured in two laboratory-scale reactors. One is the
biofilter with a mixture of sieved compost and diatomaceous
earth particles as the filter material, and another is the
trickle-bed bioreactor with diatomaceous earth particles as the
reactor material, on both which the microorganisms were
immobilized. The inlet concentration of TMA varied from 0.174 to
2.61 g/m3, whilethe superficial inlet gas stream velocity ranged
from 1.34 to 2.95 cm/s. In the steady state part, the removal
efficiency of trimethylamine in the biofilter and trickle-bed
bioreactor decreased as the inlet gas velocity or TMA inlet
concentration increase, and the elimination capacity of the
biofilter was 55 g/m3hr. Moreover, due to TMA easy dissolved in
the water, TMA in the trickle-bed bioreactor could reacted
aerobic nitrification, and detected nitrate in the recycle
nutrient liquid. Since nitrogen gas exited about 2% from
calculation nitrogen balance, it showed that anaerobic
denitrification did react due to the overthickness of biofilm.
In addition, compared to the model in the steady state biofilter
proposed by Tang et al., the experiment data could fit the
curves drawn by the model. In the portion of unsteady state, the
trickle-bed bioreactor could acclimate to the change the
environment better and reached to new steady state faster than
the biofilter.
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