16
2 Advantages of Hybrid Bioreactor
municipal wastewater [39, 40]. It was found that the hybrid bioreactor ensured a better
removal of nutrient than the purely attached biofilm system [41, 42]. Thalla et al. [43]
conducted laboratory experiments on activated sludge biofilm system under the influence of a composite medium and using vinasse as the substrate. It was noticed that
concentration of biomass attached in the media was higher than that in suspension.
The biomass around the media played a significant role in the overall process. Municipal wastewater containing oils and fats, dairy wastewater, meat industry wastewater,
hospital wastewater, rapeseed oil industry wastewater were also treated with hybrid
bioreactor [18, 39, 44–49].
An aerobic hybrid bioreactor was operated for 120 days at Tilanjin, China [39]
for COD and nutrients removal from municipal wastewater. The removal efficiency
of COD and ammonium nitrogen was found 76% and 72.6%, respectively.
2.4.2 Integrated Fixed-Film Activated Sludge (IFAS)
System—At a Glance
In the early 80 s, work started in the USA on integrated fixed-film activated sludge
(IFAS) system. IFAS systems add the benefits of fixed-film systems into the activated
sludge process. The additional biomass provided by introducing fixed-film media
directly into the suspended-growth reactor does not increase clarifier solid loading
that often limits the treatment capacity of existing ASP system. IFAS technology
fulfills the need for enhancing activated sludge plant capacity, with little or no additional tankage, by virtue of the additional fixed biomass. In IFAS system, a variety of
media such as structured sheet media, knitted fabric media, etc. can be used to introduce the biomass in the activated sludge basin. Nowadays, the most common material
of fabrication for media is either high-density polyethylene (HDPE) or polypropylene (HDPP) or polyurethane, which is chemically inert and can be molded into
any shape. The geometric shape and size of the media directly influence the specific
surface area and the cost of production. To make the IFAS system successful, it is
essential that the internal pores remain open to maximize the effective surface area
[27, 28]. Biomass populations in IFAS aeration basins are not susceptible to biomass
washouts during hydraulic surges as they are fixed in place and the fixed biomass
acts as a “re-seeder” to get the system returned to normal operation quickly after the
same.
2.5 Mathematical Modeling of Aerobic Fixed-Bed Hybrid
Bioreactor
In order to design a hybrid biological process, a rational and simplified model is
very much useful. A good model not only elucidates a better understanding of the
2 Advantages of Hybrid Bioreactor
municipal wastewater [39, 40]. It was found that the hybrid bioreactor ensured a better
removal of nutrient than the purely attached biofilm system [41, 42]. Thalla et al. [43]
conducted laboratory experiments on activated sludge biofilm system under the influence of a composite medium and using vinasse as the substrate. It was noticed that
concentration of biomass attached in the media was higher than that in suspension.
The biomass around the media played a significant role in the overall process. Municipal wastewater containing oils and fats, dairy wastewater, meat industry wastewater,
hospital wastewater, rapeseed oil industry wastewater were also treated with hybrid
bioreactor [18, 39, 44–49].
An aerobic hybrid bioreactor was operated for 120 days at Tilanjin, China [39]
for COD and nutrients removal from municipal wastewater. The removal efficiency
of COD and ammonium nitrogen was found 76% and 72.6%, respectively.
2.4.2 Integrated Fixed-Film Activated Sludge (IFAS)
System—At a Glance
In the early 80 s, work started in the USA on integrated fixed-film activated sludge
(IFAS) system. IFAS systems add the benefits of fixed-film systems into the activated
sludge process. The additional biomass provided by introducing fixed-film media
directly into the suspended-growth reactor does not increase clarifier solid loading
that often limits the treatment capacity of existing ASP system. IFAS technology
fulfills the need for enhancing activated sludge plant capacity, with little or no additional tankage, by virtue of the additional fixed biomass. In IFAS system, a variety of
media such as structured sheet media, knitted fabric media, etc. can be used to introduce the biomass in the activated sludge basin. Nowadays, the most common material
of fabrication for media is either high-density polyethylene (HDPE) or polypropylene (HDPP) or polyurethane, which is chemically inert and can be molded into
any shape. The geometric shape and size of the media directly influence the specific
surface area and the cost of production. To make the IFAS system successful, it is
essential that the internal pores remain open to maximize the effective surface area
[27, 28]. Biomass populations in IFAS aeration basins are not susceptible to biomass
washouts during hydraulic surges as they are fixed in place and the fixed biomass
acts as a “re-seeder” to get the system returned to normal operation quickly after the
same.
2.5 Mathematical Modeling of Aerobic Fixed-Bed Hybrid
Bioreactor
In order to design a hybrid biological process, a rational and simplified model is
very much useful. A good model not only elucidates a better understanding of the