Sewage Treatment in Campus for Recycling Purpose: A Review
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Macroalgae (seaweed) are multicellular, large-size algae, visible with the naked eye,
while microalgae are microscopic single cells and may be prokaryotic, similar to
cyanobacteria (Chloroxybacteria), or eukaryotic, similar to green algae (Chlorophyta).
Based on the review, different species of microalgae have been used in campus
sewage treatment namely S. quadricauda SDEC-13, Golenkinia sp., Scenedesmusacutus, and Euglena.sp. It is recorded to have an efficiency of 55–100% which depends
on the type of microalgae being used. In fact, it can also be combined with other
treatment such as wetland and has removal of 55% (BOD) and 100% (N–NH 3 ).
Till date, microalgae have been used as secondary treatment and tertiary treatment.
The bioremediation using algae does not limit to one species, in fact, more than one
species can be combined to treat campus wastewater as being done by Silveira et al.
(2017) with 100% removal of N–NH 3 .
The selection of microalgae for a particular treatment option can be based
on the knowledge about the indigenous species in such wastewaters, making use of their characteristics for our advantage. Several microalgae species
(such as Chlorella sp. Scenedesmus sp. or Desmodesmus sp. (Ji et al. 2014;
Martinez-Sosa et al. 2011), Neochloris sp., Chlamydomonas sp. (Xiong et al.
2016), Nitzschia sp., and Cosmarium sp. (Daneshvar et al. 2007) have been
applied for various types of wastewater treatments coupled with biofuels production. The most commonly applied species are Chlorella, Scenedesmus and
some other cynobacteria due to their high growth rate, high environmental tolerance as well as high lipid/starch accumulation potential (Wang et al. 2016).
Also, strains such as Oscillatoria, Scenedesmus, Chlorella, and Nitzschia have
been ranked as the most pollution-tolerant microalgae in wastewater treatment systems (Colzi Lopes et al. 2018). Chlorella sp. is widely applied in the wastewater treatment because of its enhanced ability in removing nitrogen, phosphorus, and chemical oxygen demand https://www.sciencedirect.com/topics/earth-andplanetary-sciences/chemical-oxygen-demand (COD), while Scenedesmus sp. can
be cultivated in high piggery wastewater (Kim et al. 2016), and high CODloading swine https://www.sciencedirect.com/topics/agricultural-and-biologicalsciences/swine wastewater (Prandini et al. 2016). Zhou et al. (2011) had isolated
microalgae strains from various wastewater treatment sites and found that five strains
(of the genera Chlorella sp., Hindakia sp., Scenedesmus sp., and Auxenochlorella
protothecoides) recorded higher biomass and lipid productivity.
Optimal growth temperatures for most microalgae species are in the range of
15–35 °C. Under low temperatures, lower growth rates are recorded while high temperatures may result in oxidative stress (Posadas et al. 2017). On the other hand,
a positive correlation between the photoperiod and microalgae growth is expected,
although a long light exposure and high irradiance may result in growth photoinhibition and culture photodamage. For instance, Chlamydomonas reindhardtii, Chlorella
vulgaris, and Scenedesmus obliquus grown independently in swine WW showed
higher biomass productions and greater nutrient removal rates at 23 °C and 14/10 h/h
light/dark cycles (irradiance of 5500 lx) than at 15 °C and 11/13 h/h light/dark cycles
(Molinuevo-Salces et al. 2016).
223
Macroalgae (seaweed) are multicellular, large-size algae, visible with the naked eye,
while microalgae are microscopic single cells and may be prokaryotic, similar to
cyanobacteria (Chloroxybacteria), or eukaryotic, similar to green algae (Chlorophyta).
Based on the review, different species of microalgae have been used in campus
sewage treatment namely S. quadricauda SDEC-13, Golenkinia sp., Scenedesmusacutus, and Euglena.sp. It is recorded to have an efficiency of 55–100% which depends
on the type of microalgae being used. In fact, it can also be combined with other
treatment such as wetland and has removal of 55% (BOD) and 100% (N–NH 3 ).
Till date, microalgae have been used as secondary treatment and tertiary treatment.
The bioremediation using algae does not limit to one species, in fact, more than one
species can be combined to treat campus wastewater as being done by Silveira et al.
(2017) with 100% removal of N–NH 3 .
The selection of microalgae for a particular treatment option can be based
on the knowledge about the indigenous species in such wastewaters, making use of their characteristics for our advantage. Several microalgae species
(such as Chlorella sp. Scenedesmus sp. or Desmodesmus sp. (Ji et al. 2014;
Martinez-Sosa et al. 2011), Neochloris sp., Chlamydomonas sp. (Xiong et al.
2016), Nitzschia sp., and Cosmarium sp. (Daneshvar et al. 2007) have been
applied for various types of wastewater treatments coupled with biofuels production. The most commonly applied species are Chlorella, Scenedesmus and
some other cynobacteria due to their high growth rate, high environmental tolerance as well as high lipid/starch accumulation potential (Wang et al. 2016).
Also, strains such as Oscillatoria, Scenedesmus, Chlorella, and Nitzschia have
been ranked as the most pollution-tolerant microalgae in wastewater treatment systems (Colzi Lopes et al. 2018). Chlorella sp. is widely applied in the wastewater treatment because of its enhanced ability in removing nitrogen, phosphorus, and chemical oxygen demand https://www.sciencedirect.com/topics/earth-andplanetary-sciences/chemical-oxygen-demand (COD), while Scenedesmus sp. can
be cultivated in high piggery wastewater (Kim et al. 2016), and high CODloading swine https://www.sciencedirect.com/topics/agricultural-and-biologicalsciences/swine wastewater (Prandini et al. 2016). Zhou et al. (2011) had isolated
microalgae strains from various wastewater treatment sites and found that five strains
(of the genera Chlorella sp., Hindakia sp., Scenedesmus sp., and Auxenochlorella
protothecoides) recorded higher biomass and lipid productivity.
Optimal growth temperatures for most microalgae species are in the range of
15–35 °C. Under low temperatures, lower growth rates are recorded while high temperatures may result in oxidative stress (Posadas et al. 2017). On the other hand,
a positive correlation between the photoperiod and microalgae growth is expected,
although a long light exposure and high irradiance may result in growth photoinhibition and culture photodamage. For instance, Chlamydomonas reindhardtii, Chlorella
vulgaris, and Scenedesmus obliquus grown independently in swine WW showed
higher biomass productions and greater nutrient removal rates at 23 °C and 14/10 h/h
light/dark cycles (irradiance of 5500 lx) than at 15 °C and 11/13 h/h light/dark cycles
(Molinuevo-Salces et al. 2016).