2010), each of which has advantages and disadvantages due to the processing of
raw materials and limitations. However, there is a significant focus on the growth of
microalgae specifically for biodiesel applications (Soh et al. 2014).
The literature in this field does not fully address the fundamental stages of life
cycle application. However, it is only mentioned that the main challenges associated with the production of biofuels in the environment are related to the raw
material and its significant influence on the high-energy consumption required.
Moreover, literary efforts are limited. In this context, Table 1 shows surveys that
report the main parameters implementing the LCA, where the main focus is to
establish the net energy index and greenhouse gas emissions. Nevertheless, most
studies are lacking information on the use of water resources (Živković et al. 2017).
On the other hand, the literature reports the most diverse objectives of establishing LCA. Among the most cited are lipid extraction methods and studies that
reduce energy input at harvest, centrifugation, and drying, as these are the main unit
operations of the microalgal biomass production unit (Chen et al. 2011; Laamanen
et al. 2016).
In addition, since the main operations included in microalgae cultivation are
exposed in the scope of work, the objective is to establish and provide a solid basis
for the implementation of zero carbon emissions, with the purpose of consolidating
integrated biorefineries to produce biofuels of microalgae (Medeiros et al. 2015;
Klein et al. 2017).
As a result of the implementation of biorefineries, the distribution of environmental costs or loads in a multiproduct system provides the emergence of the
allocation issue. Consequently, the biggest bottleneck in implementing the LCA is
to establish the best scenario and its allocation in order to process the products
without neglecting the quantification of the necessary inputs of the system (Silva
et al. 2017).
It is known that microalgal biomass presents a diverse range of products to be
exploited from the defatted biomass. Therefore, defining a system boundary, which
makes it possible to extract all co-products from this residue, makes the system
boundary unlikely and complex.
At the same time, it is necessary to estimate scenarios that determine exactly
which process will be chosen. Figure 2 shows the scope of three different scenarios
of a biorefinery for the production of microalgae biodiesel. Moreover, since
bioenergy includes low-value but high-volume biofuels such as biodiesel. In contrast, high-value but smaller-volume co-products are designed to increase the
profitability of biorefineries (Chew et al. 2017). Therefore, at the same time as bulk
chemicals such as defatted biomass can be obtained, fine chemicals such as pigments can increase the economic profitability of bioprocesses (Jacob-Lopes and
Franco 2010).
6 Life Cycle Assessment of Biofuels from Microalgae
147
raw materials and limitations. However, there is a significant focus on the growth of
microalgae specifically for biodiesel applications (Soh et al. 2014).
The literature in this field does not fully address the fundamental stages of life
cycle application. However, it is only mentioned that the main challenges associated with the production of biofuels in the environment are related to the raw
material and its significant influence on the high-energy consumption required.
Moreover, literary efforts are limited. In this context, Table 1 shows surveys that
report the main parameters implementing the LCA, where the main focus is to
establish the net energy index and greenhouse gas emissions. Nevertheless, most
studies are lacking information on the use of water resources (Živković et al. 2017).
On the other hand, the literature reports the most diverse objectives of establishing LCA. Among the most cited are lipid extraction methods and studies that
reduce energy input at harvest, centrifugation, and drying, as these are the main unit
operations of the microalgal biomass production unit (Chen et al. 2011; Laamanen
et al. 2016).
In addition, since the main operations included in microalgae cultivation are
exposed in the scope of work, the objective is to establish and provide a solid basis
for the implementation of zero carbon emissions, with the purpose of consolidating
integrated biorefineries to produce biofuels of microalgae (Medeiros et al. 2015;
Klein et al. 2017).
As a result of the implementation of biorefineries, the distribution of environmental costs or loads in a multiproduct system provides the emergence of the
allocation issue. Consequently, the biggest bottleneck in implementing the LCA is
to establish the best scenario and its allocation in order to process the products
without neglecting the quantification of the necessary inputs of the system (Silva
et al. 2017).
It is known that microalgal biomass presents a diverse range of products to be
exploited from the defatted biomass. Therefore, defining a system boundary, which
makes it possible to extract all co-products from this residue, makes the system
boundary unlikely and complex.
At the same time, it is necessary to estimate scenarios that determine exactly
which process will be chosen. Figure 2 shows the scope of three different scenarios
of a biorefinery for the production of microalgae biodiesel. Moreover, since
bioenergy includes low-value but high-volume biofuels such as biodiesel. In contrast, high-value but smaller-volume co-products are designed to increase the
profitability of biorefineries (Chew et al. 2017). Therefore, at the same time as bulk
chemicals such as defatted biomass can be obtained, fine chemicals such as pigments can increase the economic profitability of bioprocesses (Jacob-Lopes and
Franco 2010).
6 Life Cycle Assessment of Biofuels from Microalgae
147