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To improve the deficiencies of the traditional Aerated
Submerged Filters (ASF) in removing Nitrogen and Phosphorus ,a
study of treating domestic sewage from the Taipei Min- Seng
Domestic Sewage Treatment Plant by operating an ASF with
intermettent aeration patterns of different aeration time
scales(100％, 75％ and 50％ of the Hydraulic Retention Time,
HRT) was conducted. The results of the studies are found as
follow: 1.Under the condition of 75％ aeration time scales of
an 8 hours'' HRT, a 61％ TN removal can be accomplished, and of
an 12 hours'' HRT, a 77％ amonia nitrogen removal can be
accomplished. 2.While the influent ratio of TBOD/TN =3.23,
SBOD/TN =1.3, a 64％ TN removal can be accomplished. In the
other hand, and the influent ratio of TBOD/TN=1.79, SBOD/
TN=0.38, only 1％ TN is removed. 3.Every substrate has a
linear relationship between the unit area loading rates and
unit area removal rates. For example, the relationship is Lr =
0.88Lo + 0.024 for TBOD under the condition of 100％ aeration
time scales. 4.The unit area removal rate is 0.196 g amonia
nitrogen per squared meter per day under the condition of
100％ aera- tion time scales when the unit area loading rate
is 0.3g amonia nitrogen per squared meter per day. 5.Because of
the low wash-out frequency of Biomass, the removals of TP
were not obvious in the intermettent aeration systems.
6.When the unit area loading rates are higher than 0.256g TN/
per squared meter per day, the operation of 75％ aera- tion
time scale can obtain higher unit area removal rates
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