Agriculture Reference
In-Depth Information
glucose (BOD
5
to TN ratio of 100:10) and HRT of 10 days (organic loading
of 0.008 kg BOD
5
/m
3
day, CN
loading of 0.86 g/m
3
day, and Zn
2+
loading of
1.2 g/m
3
day). Lotito et al. (
2012
) address the characterization of the sludge
produced from sequencing batch biofilter granular reactor (SBBGR) in terms of
some physical properties (settling properties, dewaterability, rheology). The results
show that such sludge is characterized by good settling and dewatering properties,
adding a new advantage for the full-scale application of SBBGR technology. Janus
(
2014
) developed an integrated model for MBR reactor, which was composed of
three interconnected submodels: the activated sludge model (ASM) extended with
soluble and bound biopolymer kinetics, the membrane fouling model, and the
interface model relating cake back-transport rate to air-scour intensity and specific
cake resistance to concentration of extracellular polymeric substances (EPS). Sim-
ulation methods of a system dynamics model for activated sludge wastewater
treatment plants were developed by Park et al. (
2014
). A wastewater treatment
plant in South Korea was chosen for these analyses. The inflow rate beyond which
aeration tank size needs to be increased was calculated while satisfying the effluent
water quality requirement. The corresponding sizes of aeration tank were also
calculated for different activated sludge return rates under the maximum inflow
rate which does not require expansion of the aeration tank.
SBR has good removal characteristics with respect to decarbonization and
denitrification, with COD and NH
3
-N removal rates being more than 90 %. Fur-
thermore, the reactor can be controlled automatically with less area and a variety of
technologies such as ICEAS, CAST, DAT-IAT, etc., which are commonly used in
the livestock wastewater treatment process. On the other hand, SBBR is theoreti-
cally characterized by high biomass, less area, good carbonization and denitrifica-
tion performance, good aerobic granular sludge settling properties, the ability to
withstand high organic loading, and better decarbonization and denitrification;
however, practical application of this technology requires further study. Biofilter
has good sludge settling properties, high biomass, high organic load capacity, and
good decarbonization and denitrification performance and is suitable for livestock
wastewater treatment; nevertheless, further research regarding its practical appli-
cation is needed. Moreover, biofilter needs an appropriate filler with good denitri-
fication characteristics. The MBBR technology, a combination of both traditional
and biological technologies with the advantage of fluidized oxidation, is a new and
efficient method for sewage disposal. On the other hand, MBR has a longer sludge
age, higher sludge concentration, and good decarbonization and denitrification
performance, but faces a tough problem of membrane fouling that limits its further
development and implementation. Nevertheless, studies have shown that the addi-
tion of a suitable carrier and development of granular sludge are effective ways to
decrease MBR membrane fouling. Lastly, the A/O process is simple and less
equipped, and no external carbon source is needed.
