302
13 Starch
is increasingly scarce, and where available is required for consumption by humans
and farm animals. The water consumption given in Table 13.3 is the water consumed
during the extraction process. While algae do not require freshwater to grow in and
can fix nitrogen and other elements from the water for their growth, the extraction
process requires distilled water to extract purified starch.
13.7.4 CO 2 Emission
One key advantage of starch source from aquatic plants and algae is that the emission
during extraction is balanced by the CO 2 that the plant or algae removes from the
environment; it can be assumed to be a zero emission process. The process of cultivating microalgae is CO 2 negative since CO 2 is consumed in the process. For example,
in the cultivation of C. sorokiniana, the system is aerated with air containing 2% carbon dioxide at 0.02 vvm (Gifuni et al. 2017). Starch production from terrestrial plants
also involves the plan removing CO 2 from the environment; however, aquatic plants
grow at a much faster rate than some of the terrestrial plants which commonly serve
as sources of starch (Table 13.2) some also have higher starch content (Table 13.1);
therefore, the cultivation of aquatic plants and algae for starch production results in
more CO 2 removal per gram of starch produced.
For systems, where the cultivation is carried out in a bioreactor or in aquaculture
system which are within the factory where the starch is extracted, CO 2 emission from
running vehicles on fossil fuel to transport the biomass to the factory for extraction
is minimized. This is particularly for starch which the bioaccumulation of starch is
optimized by using carefully controlled growth conditions and nitrogen starvation.
13.7.5 Water Remediation
Aquatic plants and algae are able to extract impurities, mainly compounds of nitrogen
and phosphorus from wastewater. Water recycling systems which implement the
cultivation of macrophytes for production of biochemicals (Muradov et al. 2014)
such as starch for bioethanol production are an efficient and low impact means of
providing freshwater for other applications such as terrestrial crop farming which
requires clean water. This provides a solution to water pollution and contributes to
ensuring food security through providing water for plant cultivation and also a source
of third-generation renewable energy.
13 Starch
is increasingly scarce, and where available is required for consumption by humans
and farm animals. The water consumption given in Table 13.3 is the water consumed
during the extraction process. While algae do not require freshwater to grow in and
can fix nitrogen and other elements from the water for their growth, the extraction
process requires distilled water to extract purified starch.
13.7.4 CO 2 Emission
One key advantage of starch source from aquatic plants and algae is that the emission
during extraction is balanced by the CO 2 that the plant or algae removes from the
environment; it can be assumed to be a zero emission process. The process of cultivating microalgae is CO 2 negative since CO 2 is consumed in the process. For example,
in the cultivation of C. sorokiniana, the system is aerated with air containing 2% carbon dioxide at 0.02 vvm (Gifuni et al. 2017). Starch production from terrestrial plants
also involves the plan removing CO 2 from the environment; however, aquatic plants
grow at a much faster rate than some of the terrestrial plants which commonly serve
as sources of starch (Table 13.2) some also have higher starch content (Table 13.1);
therefore, the cultivation of aquatic plants and algae for starch production results in
more CO 2 removal per gram of starch produced.
For systems, where the cultivation is carried out in a bioreactor or in aquaculture
system which are within the factory where the starch is extracted, CO 2 emission from
running vehicles on fossil fuel to transport the biomass to the factory for extraction
is minimized. This is particularly for starch which the bioaccumulation of starch is
optimized by using carefully controlled growth conditions and nitrogen starvation.
13.7.5 Water Remediation
Aquatic plants and algae are able to extract impurities, mainly compounds of nitrogen
and phosphorus from wastewater. Water recycling systems which implement the
cultivation of macrophytes for production of biochemicals (Muradov et al. 2014)
such as starch for bioethanol production are an efficient and low impact means of
providing freshwater for other applications such as terrestrial crop farming which
requires clean water. This provides a solution to water pollution and contributes to
ensuring food security through providing water for plant cultivation and also a source
of third-generation renewable energy.