Similarly, the attachment rate
coefficients for poliovirus to dune sand were 35 times of that for
MS-2 bacteriophage (Schijven et al., 2003). The differences in
attachment rates of MS-2 and poliovirus changed with the negative
zeta-potential of the attached surface (Schijven et al., 2002).
Therefore, MS-2 represents the low adsorptive behaviour of negatively
charged viruses and may be considered as a worst case
scenario for virus removal. This result was supported by previous
research findings (Schijven et al., 2003).We may therefore conclude
that the most likely removal path for poliovirus and MS-2 bacteriophage
in our system was adsorption onto the activated sludge
flocs. The difference of the log removal was due to the difference of
their attachment rates to the negative charged activated sludge.