| Summary: | 碩士 === 逢甲大學 === 土木及水利工程研究所 === 85 === Two digesters, aerobic and anaerobic, were used to treat septage
with sludge retention time (SRT) of 30, 20, 15, 10 and 5.3
days. At SRT of 30 days or organic loading of 178 g-COD/m3.
day, the removal efficiencies of VS (volatilesolids), COD
(Chemical Oxygen Demand), NH3-N (Ammonia), T-p (Total
Phosphorus),saccharide and protein were respectively higher than
43, 89, 90, 77, 64 and 52percent for aerobic digestion, and
higher than 40, 84, 57, 65, 65 and 57 percent for anaerobic
digestion. The removal rates of COD, NH3-N, totalphosphorus,
saccharide and protein were 159, 10.8, 0.6, 5 and 2.4 g /m3.day
foraerobic digestion, and 150, 8, 0.4, 5 and 2.6 g-COD/m3.day
for anaerobicdigestion at SRT of 30, 20, 15, 10 and 5.3 days,
respectively. The treatmentefficiency of aerobic digestion was
better than that of an aerobic digestion.The dewaterability of
digested sludge was determined by capillary suction time(CST).
The CSTs were respectively 19, 15, 12.5, 10.2 and 33 seconds for
aerobicdigestion, and 67, 31, 28, 24 and 72 seconds for
anaerobic digestion for thefive SRTs. The nondegradable portion
of VSS (Volatile Suspended Solides) wasapproximately 49.6
percent of the initial total VSS concentration, resultingin the
removal efficiency of VSS of lower than 50 percent. The Kb
(batchreaction rate for degradable VSS) was 0.132 per day.The
kinetic parameters were calculated using Monod model for
anaerobicdigestion and the values of Vmax, Ks, Yg and Kd were
3.34 day-1, 236 mg COD/L,0.3 mg VSS/mg COD and 0.014 day-1,
respectively. A series of batch tests withserum bottle was used
to analyze the effects of heavy metals on the VFA degradation
and methane production. The dosages at 45 mg Cu+2/L, 12 mg Ni+2/
L,29 mg Zn+2/L, 33 mg Fe+3/L and 1.4 mg Mn+2/L can promote VFA
degradation andenhance methane production efficiency for
anaerobic digested sludge with SRTof 5.3 days.
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