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Potential of Microalgae as a Promising Source for Biofuel Production in Nile Basin Countries

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Abstract

The Nile Basin countries have a huge comparative advantage in land, labor and good climatic conditions favorable for microalgae as a source of bioenergy. This paper provides an overview of microalgae as a promising source for biofuel in the Nile Basin countries due to their high photosynthetic efficiency, the ability to grow rapidly and their ability to produce lipids (approximately 20–50% of dry weight), a biodiesel feedstock All of these properties render them an excellent source for biofuels such as biodiesel, bioethanol and bio-methane. This paper calls the Nile Basin countries to develop appropriate strategies, plans and frameworks to harness the potential economic opportunities from biofuels sector development, taking into account protecting the environment and rural communities. It is obvious that Microalgae fuel is not the Magic solution for entire needs for development in the Nile basin, but it can make a significant contribution with the other types of biofuels. The benefits, challenges, fields of cooperation and policy needs of using algae as a source of biofuel are also discussed. Keywords: Microalgae, biofuels, Nile basin and environment
Water and energy potential of Integration and Development Conference
Studies Centre Sudan-African Research and Studies Institute - Cairo University 72
Potential of Microalgae as a Promising Source
for Biofuel Production in Nile Basin Countries
Karim S.Metwaly*, Hassan M. Sobhy and Mohamed S. Abbas
Natural Resources Department, Institute of African Research and Studies, Cairo
University, 12613, Cairo, Egypt
*Corresponding author:kareem_metwalee@yahoo.com
ABSTRACT
The Nile Basin countries have a huge comparative advantage in land,
labor and good climatic conditions favorable for microalgae as a source
of bioenergy. This paper provides an overview of microalgae as a
promising source for biofuel in the Nile Basin countries due to their high
photosynthetic efficiency, the ability to grow rapidly and their ability to
produce lipids (approximately 2050% of dry weight), a biodiesel
feedstock All of these properties render them an excellent source for
biofuels such as biodiesel, bioethanol and bio-methane. This paper calls
the Nile Basin countries to develop appropriate strategies, plans and
frameworks to harness the potential economic opportunities from biofuels
sector development, taking into account protecting the environment and
rural communities. It is obvious that Microalgae fuel is not the Magic
solution for entire needs for development in the Nile basin, but it can
make a significant contribution with the other types of biofuels. The
benefits, challenges, fields of cooperation and policy needs of using algae
as a source of biofuel are also discussed.
Keywords: Microalgae, Biofuels, Nile Basin and environment
INTRODUCTION
The world faces the risk of increasing demand for energy (fossil fuels
in particular) and in recent years (the last two decades of the twentieth
century, and until now). Because of this increase in demand for fuel
(especially from the United States, China and India) as well as the
decreasing of the reserves in addition to the environmental hazards
caused by the burning of fossil fuels.
The world in a hectic search for alternative energy solutions and one of
these solutions are Microalgae. However, Chisti (2007)reported that
Water and energy potential of Integration and Development Conference
Studies Centre Sudan-African Research and Studies Institute - Cairo University 73
Microalgae well be the main and only source of renewable for biofuel
meet the global demand for transportation fuels.
In the recent decades Microalgae based biofuel received a lot of
attention as a promising source of renewable energy, due to the
Microalgae features such as, high oil and carbohydrate content, do not
require agriculture land or fresh water.
This paper well focus on Microalgae production and the potential for
algae oil production in the countries of the Nile Basin.
Algae: Basic Concepts:
Microalgae are a very large group of simple photosynthetic organisms
were among the first life forms on earth. Live in the aquatic habitats
(bogs, marshes, swamps, salt marshes and salt lakes) (AyhanDemirbas,
2010),Microalgae be able to endure extreme temperatures and lack of
water and they are capable of fixing large amounts of CO2(Al Darzinset
al., 2010).
Number of algae in the world is still under study, but the most recent
estimate is 72,500 algal species worldwide (Guiry, 2012).
Fuel Production from Microalgae:
There are three major components can be extracted from Microalgae
biomass, lipids, carbohydrates, and proteins. These components can be
converted into many kinds of fuel like biodiesel, fuel jet, and biogasoline.
The lipids (which are founded in the membrane that surrounded the
cells) are the key in the biofuel production, with the high energy content,
chemical components such as hydrocarbon molecules and
triacylglycerides (TAGs), can be converted into biofuels.
A comparison of the oil productivity between microalgae and energy
crops:
Water and energy potential of Integration and Development Conference
Studies Centre Sudan-African Research and Studies Institute - Cairo University 74
One of the main features of Microalgae is the higher photosynthetic
efficiency, which is reflected on the oil production per unit area. When
compared to other energy crops.
Algae-based biofuels advantages:
Algae-based biofuels have many advantages especially when we
compared with the 1st and 2nd generation of biofuel, these advantages can
be summarized in the following points:
Microalgae are one of the most prevalent organisms on Earth's surface.
And the fastest-growing photosynthesizing organisms (Gupta and
Demirbas, 2010).
Microalgae can double their biomass in 24 hours under optimal
conditions (Chisti, 2007; Mata et al., 2009; Rosenburget al., 2008;
Tsukahara and Sawayama, 2005)
Microalgae are not considered as food for humans; therefore,
microalgae do not compete with agriculture crops and do not cause a
rise in food prices.
The oil productivity of microalgae is greater than the other energy
crops, oil content in the range of 2050% dry weight of biomass.
(Singh and Gu, 2010; Gupta and Demirbas, 2010).
Microalgae can be grown in any kind of water (fresh water sea water
- brackish water - etc.) (Mascarelli 2009)and on nonarable lands.
Consume large amounts of carbon dioxide, therefore working to purify
the atmosphere, and reduce emissions of carbon dioxide.
The nutrients for the Microalgae cultivation can be obtained through
(wastewater) sewage, and at the same time Microalgae can play a great
role in wastewater treatment (Tsukahara and Sawayama, 2005).
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Microalgae cultivation produce many valuable co-products like
proteins and biomass that can be used in may important industries like
animal feed, medicines and fertilizers, and others.
Algae cultivation does not need herbicides or pesticides (Sahooet al.,
2012).
Microalgae growth requirements:
Growing microalgae for biofuel production requires a few factors:
Temperature:the maximum productivity for Microalgae can
be achieved at zones with temperature above 15°C, which are
located between 37°north and south latitude (Harmelen and Oonk,
2006).
CO2:Microalgae use CO2 as a carbon source and the CO2 in
limiting factor on the growth and oil productivity, approximately
1.8 tonnes of CO2 are needed to grow 1 tonne of biomass. Also, the
Microalgae cultivation need a source of CO2 pumped into the
cultivation system. The main sources for CO2 are factories (cement
factories) (Piccolo, 2009) and oil refineries (Harmelen and Oonk,
2006).
Nutrients:Microalgae need nutrients to grow especially
nitrogen (N) and phosphorus (P) (Greer,2009), these can be
obtained from agricultural fertilizers, or from wastewater
Land:the suitable land located at altitudes lower than 500m.
with moderate slops.
Water:Microalgae can be grown in any kind of water, they
don't compete for fresh water resources like other energy crops
(Mascarelli 2009).
Algae Cultivation:
There are two main ways for commercial Algae-based biofuel
production:
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1. Open pond system: It's also called raceway pond, and it's the
oldest and simplest way for mass cultivation. The open pond
systemis a shallow artificial pond (15 cm to 35 cm deep).made
from plastic or cement or clay-based (unlined) to reduce capital
cost.The pond is equipped with a paddle wheel to cycling the
contents of the pond continuously. This system is used with the
high-oil content algae. The main advantages of open pond systems
are simplicity, capital and operating costs are lower than the other
ways (Rapier, 2012).
Cyanotech in Hawaii (75000 m2 pond areas) and Earthrise Farms
in California (150000m2 pond areas) Considered one of the major
and large open pond systems in the world (Lee, 1997; Tredici
2004)
2. Photobioreactors (PBR’s):PBR's are closed systems of
transparent plastic or borosilicate glass tubes (in many shapes like
cylindrical tubes, flat plates, or bags) (Rapier 2012) exposed to
sunlight. This system is more controlled than the open pond
system, especially in the protection from contamination and
predators, and other climatic factors.
Harvesting and oil extraction from microalgae:
Cell disruption is the basic step to obtain the main products from
Microalgae cells, the most commonly used methods are mechanical
disruption such as bead-beating, ultrasound and steam extraction and non-
mechanical disruption, including application of organic solvents and
addition of inorganic acids and alkali for pre-treatment processing
(Murphy et al., 2013)For oil and other products extraction, the chemical
solvents can be used (Hexane is the most commonly used solvents)
(Murphy et al., 2013)Residual materials such as carbohydrate and
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proteins can be converted into several products like ethanol and animal
feed. (Murphy et al., 2013)
Improving the Economic Viability of Algal Biofuels:
At the beginning of 2009, the production of biofuels from Microalgae
is still in the early stages, where the price of a gallon of oil from
microalgae about $ 21. But with evolution of researches especially
bioprospecting, engineering, breeding and bioengineering to improve the
processes, besides by-products that were produced alongside oil
production ; the cost began decreasing significantly to be between $ 6 to
$3 for gallon in 2014. And the costs are expected to decrease to less than
one dollar in the period between 2018 and 2025. (Hannon, 2010)
Some models for the production of oil from Microalgae in some
developing countries:
There have been many experiments for the production of biofuels from
Microalgae in some developing countries, including some African
countries have had these experiences on their lands and the results were
promising and successful in the potential for good productivity of
biofuels:
Pilot commercial algal production facilities conconsists of the tow
cultivation systems the open ponds for algae mass culture in Egypt
with different sizes (0.01 m2 10 m2 100 m2 1000 m2) were
constructed in Suez, Egypt, by a scientific team under the
leadership of Associate Prof Mohammad I. Abdel-Hamid (Faculty
of Science, Mansoura University) with outdoor photobioreactors.
In spite of the high cost of one pond (1.100.800 US$) could be
considered as asset value. The annual mass production of one open
pond is 158 t 315 t dry wt/ year (Abdel-Hamid, 2010).
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Pilot algal facility open pond constructed in Tunisia in a
framework of a cooperation between Tunisia and Italy, the annual
oil production from 18 t oil ha-1 year -1 (Tredici, 2012).
Pilot plant constructed in South Africa for producing Ethanol, it
was 20m2 raceway with 0.55 kW paddle drive with algae density 4
gram/litreproduced50 - 70 ml ethanol/m2/day. This Pilot plant
designed for ethanol production for emerging farmers (Zietsman,
2009).
The potential of the Nile Basin countries in the production of biofuels
from microalgae:
The Nile basin countries have a lot of features make them suitable for
Microalgae cultivation:
- The warm climate (+ 15°C throughout the year).
- High annual solar irradiances.
- Large areas ofnonarable land lands.
- Large costs areas on the Mediterranean and the Red Sea and the
Indian Ocean.
- Plenty of different water resources (fresh water sea water
brackish water).
- Cheaplabor.
- CO2 emissions form cement factories and oil refineries.
- Scientific base in some countries, especially Egypt is able to
supervise, processing, production and marketing.
From these points we found that Nile Basin countries possess a great
potential for Microalgae biofuel production, countries like Egypt, Sudan,
Ethiopia, Kenya and Tanzania have a lot of features especially
appropriate temperatures and vast unused lands. Moreover, these
countries are developing countries and in greatest need of energy
resources to build their economies.
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And the both cultivation systems would be probably be efficient and
suitable to grow the algae, especially after considering the requirements
of the growth of microalgae, especially temperature and nonarable lands,
which already taking them up in the context of this research paper. Which
show how Africa lies entirely within the range of the suitable climatic and
land conditions for the growth of micro-algae especially area of the Nile
Basin.
The cement factories and oil Refineries are good sources for CO2
emissions; Egypt is considered one of the leading and greatest cement
producers in the world (16 factories, producing 46 million tons/year)
(Askaret al., 2010). The second country in the Nile Basin is Kenya with 8
factories, and Sudan and Ethiopia with 4 for each one of them. (Global
Cement Directory, 2013) and There are opportunities to establish a
cement projects in the Nile Basin countries in the next years.
And with a close look to East Africa countries we find that s CO2
emissions increased from 18 million tonnes to 21 million tonnes between
2005 and 2009 (Eyakuze and Salim, 2012).
Oil refineries are also a good source for CO2 emissions; Egypt has 9
refineries mostly concentrated in the northeast (Cairo, Alexandria, Suez).
3 oil refineries in Sudan.
The economic factor ( finance ) is the most important factors in the
process of the production of biofuels from Microalgae, especially because
Nile Basin countries are developing countries , for example the countries
of East Africa ( Kenya, Tanzania, Rwanda, Burundi and Uganda ) , the
economies of these countries increased in the period 2000 and 2010, from
of 32 billion dollars to 79 billion dollars , and attracted many foreign
investments which rose from 688 million dollars in 2007 to 1.7 billion
dollars in 2010 (Eyakuze and Salim, 2012). As for the rest of the basin
countries, Egypt has 6,712 billion of foreign direct investment, while
Water and energy potential of Integration and Development Conference
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Sudan 2,682 billion and Ethiopia about 222 million dollars and the
Democratic Republic of Congo about a billion dollars.
Instead of direct these investments in the production of energy crops,
which caused a lot of problems for many of the basin countries especially
Ethiopia, Tanzania and others, these investment should be directed for the
benefit of the people, taking into account the conservation of natural
resources. Especially after we present the modefor three African countries
experiments, Egypt, Tunisia and South Africa in the production of
biofuels from Microalgae and after we reviewed the features of the Nile
Basin countries through which we can produce a new generation of fuel
for the development of the basin countries.
Conclusion:
As we show in this paper the Microalgae biofuel in a promising source
for fuel for the Nile Basin countries, and these countries should working
together to find a way in cooperation for the coming years to avoid an
energy crisis ravaging the whole region.
It is obvious that Microalgae fuel is not the Magic solution for entire
needs for development in the Nile basin, but it can make a significant
contribution with the other types of biofuels.
Microalgae farms can be established in the Nile Basin countries, due to
the appropriate climatic and geographical conditions, the production costs
may high in the beginning but in the long run will have an economic
benefit, environmental and developmental yield.
So there must be a development plan based on the direct a part of
foreign direct investments in this type of fuel and cooperation among the
basin countries create a state of integration between them, for
development and meet the challenges of the future.
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