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15 Photobiological Reactors for the Degradation of Harmful Compounds in Wastewaters
of Lac-S were 30%, 40%, and 50% at 0, 10, and 20 ∘C respectively. The half-lives at
50, 60, and 70 ∘C were 21.7, 9.7, and 1.5 hours, respectively. The results provide
a compelling basis for further utilization of E. crassipes. Recent study confirmed
that E. crassipes, an abundant waste in China, could be used as the sole substrate
for laccase production by P. sanguineus SYBC-L1 in SSF. The maximum laccase
production has been achieved on the agro-industrial solid substrates (E. crassipes
and sawdust) without adding any other costly carbon or nitrogen source. The
Lac-S showed high stabilities over a broad range of pH and temperature, and
more notably, Lac-S was found to be not only a thermostable enzyme but also a
cold-adapted enzyme [12].
15.2.1.11
Algae–Bacteria Interaction in Photo-Bioreactors
Recent work presents a simple model to describe the consortia of algae–bacteria
in a photo-bioreactor. The model is influenced by the structure of activated sludge
model (ASM), which includes different process rates and stoichiometric parame-
ters, and it comprises two main biomass populations (algae and bacteria), two dis-
solved substrates (ammonium and nitrate), and two dissolved gases (oxygen and
carbon dioxide) in the reactor. The model was calibrated with data from batch exper-
iments performed in two lab-scale photo-bioreactors where a sensitivity analysis was
done to identify the parameters to be considered for the model calibration. Results
show that the maximum algal and bacterial growth rate, bacterial growth yield, and
half-saturation constant for carbon were the most sensitive parameters. Recent work
presents a simple model to describe the interaction between algae and bacteria in
a photo-bioreactor. Inspired by the ASMs framework, the aim of the model was to
predict the dynamics of the dissolved ammonium, nitrate, and oxygen concentration
considering the principal reactions and components involved in the process. A sen-
sitivity analysis was used to identify the key model parameters for calibration, where
experimental data from two lab-scale photo-bioreactors was used, and the proposed
model can give a good prognosis of the experimental values [13].
15.2.1.12
Photo Sequence Batch Reactor
In recent study, photo-sequencing batch reactors (PSBRs) were set up to evaluate
the effect of photoperiod (i.e. 24 hours illumination and 16 hours/8 hours light–dark
cycle) on NH4
+-N removal performance of algae–bacteria consortium under
long-term low-light intensity condition, and it was observed that constant NH4
+-N
removal rate (60 mg N/l/d) was achieved in both photoperiods at low light intensity
(LI) (1000 lx). Longer photoperiod favored higher production of biomass. The
16 hours/8 hours light–dark cycle condition produced less biomass but showed
same nitrification rate and slightly higher denitrification efficiency (30 mg/l) than
the reactor that was operated at 24 hours brightness. The results of a recent study
demonstrated that use of algae–bacteria consortia could be a sustainable and
cost-effective method to treat NH4
+-N-loaded wastewater, and this study also used
PSBRs, which operated at low-light intensity (1000 lx), hydraulic retention time
(HRT) of 2 days, and solid retention time (SRT) ranging from 5 to 13 days, to treat
wastewater loaded with 130 mg N/l. A daily ammonium removal rate of 60 mg N/l/d