An advantage shown by the biofiltration technology is the
capacity to retain suspended particles which contribute to increase
effluent turbidity and may potentially cause deterioration
of the effluent quality. Hence, the turbidity of the influent
and effluent of the biofilter was continuously monitored (data
not shown). The average turbidity of the influent and effluent
flows corresponded to 3 and 1 NTU, respectively, which implies
a removal of higher than 60 %.