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Production of algae coupled to anaerobic

digestion in a closed vessel system for bio
-
fuel production
.












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Authors:
,
Benjamin Maris, Jonatan Wauthier

Elke Knoops, Serpil

Dirikan,
Christophe Lisbe,


Mouna Tajeddine and

Pieter Sas

Date:
2010
-
2011

Project leader:

Lic. Bart
Cornelis


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Algae, everyone knows it. It's green, slimy and
when you are swimming in the sea it tickles
your toes. Already, several projects have
demonstrated that algae are also convenient;
they can be used as food additives: thickening
agents, but they could also be a possible
solution for the rising global fuel
prices and the
global warming issue. Even with a necessary
input of energy for the production process of
algae. The usage of algae’s is a carbon
dioxide neutral process, because of their
process of photosynthesis, which they use for
their growth. Further,
they are also an
important sustainable source of biomass for
biogas production as well as lipid for biodiesel
production, with several advantages over the
current biomass sources such as rapeseed.
This article, will tell you more about the
cultivation of a
lgae, the production of bio
-
fuels,
the Advantages and disadvantages and the
genetic engineering of algae to obtain a higher
yield of both oil to biomass. Want to know
more about it?


Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.



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SUMMARY

................................
................................
................................
................................
...............

1

1.

What is renewable energy ?

................................
................................
................................
............

1

2.

What is Bio
-
fuel and how can it be produced?

................................
................................
...............

1

3.

What are algae’s and their composition?

................................
................................
.......................

2

4.

Advantages and disadvantages of using algae.

................................
................................
...............

3

5.

Cultivation methods of algae’s

................................
................................
................................
........

3

6.

How does the production process of bio
-
fuel with algae’s occurs?

................................
...............

4

7.

Positioning of the alga
e research:

................................
................................
................................
...

6

8.

Manipulation of algae to obtain a higher profitability

................................
................................
....

6

9.

Applications within the bio
-
energy field

................................
................................
.........................

7

CONCLUSION

................................
................................
................................
................................
...........

8

10.

References

................................
................................
................................
................................
...

9


Production of algae coupled to anaerobic

digestion in a closed vessel system for bio
-
fuel production
.


1

Production of algae coupled to an
aerobic digestion in a
closed vessel system for bio
-
fuel production
.

S
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M
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A
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Y
Y





Renewable bio
-
fuels are needed to displace the current used fuels, which contribute to global
warming and are of limited availability. A possible answer will be discussed in this article, it is about

using “algae production coupled to an anaerobic digestion in a closed vessel system” for bio
-
fuel
production”. At first we discussed what renewable energy and the different generations

of it.
W
hat
bio
-
fuel is
/are

and how it can be produced. Then the article go’s about the algae
’s what they are and
what
the advantages and disadvantages are by the use of algae.

Followed about the discussion
about the different
cultivation methods of the algae

such as a closed syst
em called photobioreactors
or a open race pond
. Further we
will also position the research about
optimization

the production /
cultivation and manipulation of algae’s .

At last there are a few applications explained about the use
of algae to produce bio
-
en
ergy
, such as using algae for biogas production or the usage of algae in
for bio
-
fuel production. Followed by a small
interview with a company

in the Netherlands

that

is
already using

algae
’s

for bio
-
fuel production.


1
1
.
.


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?
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Renewable energy is energy
from i
nexhaustible (re
-
) sources.
Thi
s
hydro
power
, wind,
geothermal, biomass and all
forms of solar energy are a
example of an
inexhaustible
source. Using renewable energy
is better for the environment and
makes us less dependent on
fossil fuels which

are

e
xhaustive
and highly polluting.

Besides
renewable energy
there
is also
durable energy, often
knew
as
synonyms. This is
incorrect,
durable energy has been a
broader term than renewable
energy. It is the energy that
mankind has indefinitely,
extracted from an inexhaustible
source, and whose use is not
detrimental to our environ
ment
as well as for the economy


In other words,

durable energy is
always a renewable energy, but
renewable energy is not always
a durable energy. As recently
reported in

the media is
bio
-
fuel
from rapeseed
not a durable
source of energy
, if

for the
growth of these
rapeseed fields
forests

has to be

cut

down
.

Further the EU leaders decided
on December 2008, to

ada
pt

a
comprehensive package of
measures to reduce emissions.
Under this plan, the share of
renewable energy increased to
20%. But also to the
consumption of fossil fuels for
transport by 10% be
replaced by
bio fuels, electricity or hydrogen.

(Biofields
-
Renewable&Sustainable Energy
2009;Bond Beter Leefmilieu 2010;De
portaalsite van de Europese Unie
2010;E.Cor
nelis et al. 2009;Ghent Bioenergy
Valley
-
vzw. 2010;Milieu Centraal
2010;Organisatie Duurzame Energie
2010;Wout Boerjan 2010)

2
2
.
.


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Bio
-
fuels are fuels obtained from
biomass or from components
(from any biological origin), such
as plants. They replace the fossil

fu
els such as gasoline or diesel
,
with the advantage that bio
-
fuels
emit less particulate matter and
carbon dioxide.

There are several distinct types
of bio
-
fuels such as bio
-
ethanol
(made from sugar beet and sugar
cane) and biodiesel (made from
rape, maize and soybean) for
cars.
(Arno van 't Hoog, Marian van Opstal,
Arthur van Zuylen, Gera
rt Stout, &
Prof.Dr.Ir.Bert Weckhuysen 2008;Norbert
Cuiper 2010;Technische Universiteit
Eindhoven 2010)
.

The raw materials
for producing the bio
-
fuels can be
divided into three generations:

The first generation of bio
-
fuels
made from food crops (such as
cereals, maize and soybeans)
are processed by conventional

fermentation or chemical
processes into fuels. The
downside of this generation of
bio
-
fuels is that the precious food
crops are used for energy while
there is a food shortage in the
world. One consequence is the
emergence of second generation
bio
-
fuels,
which are bio
-
fuels
produced from
crop residues
(waste) such as wheat straw and
other 'low quality' biomass, such
as trimmings. In other words, the
second generation of bio
-
fuels
does not need to compete with
available agriculture land.

cooking oil, willow, wood and

garden waste.
L
ike after the first
generation of bio
-
fuels there is a
second generation, but also this
one is followed by a third
generation of bio
-
fuel. This
generation includes new
developments (+ genetic
modifications). Be
low means
including the use of algae to
produce bio
-
fuel. This biomass
has the advantage that it does
not compete with food crops or
other,
but also that this
method/development can be
used on soils that are not usable
as farmland.

(Arno van 't Hoog, Marian
van Opstal, Arthur van Zuylen, Gerart Stout,
& Prof.Dr.Ir.Bert Weckhuysen 2008;Biofields
-
Renewable&Sustainable Energy 2009;Bond
Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

2


What is BIOMASS?

Everything that grows and flourishes is biomass. There are two
main streams of biomass, crops grown specifically for energy
production and organic waste (waste). This stream of biomass can
vary from animal waste (including manure), biodegradable waste
from industrial, agricultural crops and even forest products (fruit

-
,
vegetables and garden waste (GFT).


Besides using biomass for energy production, biomass is also
interesting for production of products, namely biomass is full of
useful components. For example soy, palm oil and rapeseed oil
are useful for biodiesel, w
hile corn and sugar beet supply the raw
material for bio
-
ethanol. Currently 90% of the biomass currently
used for bio
-
fuel production: biodiesel, bio
-
ethanol and even
methane gas that is obtained by fermentation of the biomass (see
"6. How does the product
ion process of bio
-
fuel with algae's
occure?"). The European commission made the following target in
the first European directive (2003/30/EC) in 2005 to 2% of all fuel
consumption in Europe will be covered by bio
-
fuels. This figure
rises gradually to a mi
nimum rate of 5.75% for 2010.


I
n the graph below you can notice that biomass, over the years
has gained more importance. Thus, biomass energy is responsible
for 1183 gigawatt hour (GWh) in 2008. Compared with o
ther
renewable energy sources, this is more than 3 times the energy
production.
(Arno van 't Hoog et al. 2008;Bond Beter Leefmilieu 2010;Freya
Van Den Bossche 2010;Ghent Bioenergy

Valley
-
vzw.
2010;Milieu Centraal 2010)


0
200
400
600
800
1000
1200
1995
1997
1999
2001
2003
2005
2007
Gigawatt Hour (GWh)

Year

Evolution of the production from renewable
energy sources

Waste
Biogas
Biomass
Windenergy
Hydropower
Solar energy
Beter L
eefmilieu 2010;De portaalsite van de
Europese Unie 2010;E.Cornelis, K.Aernouts,
N.Renders, S.Vangee, & K.Jespers 2009;Freya
Van Den Bossche 2010;Milieu Centraal
2010;Norbert Cuiper 2010;Organisatie
Duurzame Energie 2010;U.S.Department of
Energy's (NREL) 20
10;Wageningen University
2010;Wout Boerjan 2010)

3
3
.
.


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(Micro
-
)
algae are eukaryotic
photosynthetic organisms, which
occur in aquatic environments.
They are classified under the
separate kingdom
Protista

and
can be unicellular (microalgae)
and multicellular organisms.
Algae’s are in the possess of
chlorophyll(s), so they can do on
photosynthesis. In other words
they use sunlight as an energy
source for building their biomass
such as sugar and lipids. For
this
they need the necessary
nutrients like nitrogen and
phosphorus in a ratio of 16N:1P
.
(Micro
-
) algae’s are remarkably
efficient biological factories which
are capable of taking
up/assimilate a waste form of
carbon (CO
2
) and converting it

into a high d
ensity liquid form of
energy (natural oil). The four
most abundant classes of micro
algae are diatoms
(Bacillariophyceae),

green algae
(Chlorophyceae
), blue
-
green
algae
(Cyanophyceae),
and
golden algae
(Chrysophyceae).

There is
a huge diversity of
microalg
ae.
it is estimated that

there are

approximately 500,000
species

exist

of which only
35,000 would consist of known /
described species. So
selecting
the (micro) algae species which
is best used for bio
-
fuel
production isn’t simple. For bio
-
fuel production
we seek a type of
algae that is rich in oil
components and has a high
primary production of oil(specially
for producing biodiesel), mainly
saturated fatty acids. But also
algae’s that grow rapidly
(specially for biogas production).
Most common microalgae

(
Botryococcus,
Chlamydomonas,
Chlorella, Dunaliella, Neochloris,
etc.)
have oil levels between 20
and 75% by weight of dry

biomass. They are all potential
sources for biodiesel production.

Though we should note that a
lower oil content of algae grow
faster than micro algae with high
oil content. Thus, micro
-
algae
with a 30% oil content grow 30
times faster than microalgae with
an oil content of 80%.
(Anon
2009;Fraunhofer Institute for Interfacial
Engineering and Biotechnology IGB 2010;Nick
Sazdanoff 2006;Simon Tanner
2009;Wageningen Un
iversity 2010)


We may not forget that oil from
micro
-
algae are composed of
unsaturated fatty acids such as
Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

3


linolenic

acid, may influence the
bio
-
fuel for example: biodiesel
with a high content of
unsaturated sources will oxidizes
rapidly than the conventional
diesel, causing problems with the
diesel engine. This

composition of the algae’s can be
controlled by changing the
growing conditions.

This also
means that the desired products
can be obtained by changing
environmental factors (growing
conditions) / creating a stress
environment: temperature, light,
pH, CO
2

concentration, salinity
and nutrients present. For
example by restricting the
nit
rogen concentration, the oil
content of
Neochloris
oleoabundans
will increase
.

(
2009;Simon Tanner 2009)
.
This is (all)
possible in a closed system and
li
mited in open systems.
these
two systems will be discussed
further in this article.

But in other
words, while selecting a algae
species we should look at
various parameters in selecting a
type of algae: among others on
fat content, growth rate, fatty acid
composition and culture
conditions (


determined the
formation of final products and
the location of the culture plant).
The composition of the algae’s
can you see in “
table 1: useful
components from algae”.
Next to
(micro) algae’s there are also
macro
-
algae’s; which are known
as seaweed. These can also be
used for bio
-
fuel production, but
there mainly use is for production
of agar, alginates and
carrageenans. Further macro
-
algae’s are grown in natural
enviro
nments and microalgae
mainly in open (cheap) and
closed systems on land.
(Rene
Wijffels 2010)
.
They also have also
the disadvantage that additional
steps must be taken to process
such as grinding.

( 2009;A.B.M.Sharif
Hossain et al. 2008;Biocycle Energy 2009;Jeff
Tester and Brian Neltner 2008;John Ferrell
and Valerie Sarisky
-
Reed 2008;Nick Sazdanoff
2006;Simon Tanner 2009;Step
hen Mayfield
2010;U.S.Department of Energy's (NREL)
2010;Wageningen University 2010;Yusuf
Chisti 2010)

4
4
.
.


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The use of algae has several
advantages namely they
can be
harvested in all seasons. T
hey
are rich in fats that can be used
for biodiesel production. This

application does have

the
disadvantage that the cos
t
s

for
separating the oil
from the algae
can be high (expensive)

and may
be polluting because of the
use
of solvents such as hexane for

extraction of the oil content. A

answer for this disadvantages
, to
decrease the use of solvents is
the usage

of “Ultrasonic
extraction”

(see
cadre

“Ultrasonic
extraction
”)
.

( 2009;Hielscher Ultrasound
Technology 2
009)
.

Further

they grow
very fast (20 to 30 times faster
than crops) and
the cultivation
plants can
be

placed on
land not
suitable for agriculture
,
so they
will not compete with food crops.
Algae’s are also CO
2

neutral
processes because of their
photosynthesis, in which they
accumulate carbon dioxide
during their growth and this CO
2

is back released into the
atmosphere during consumption
of bio
-
fuels based on algae. A
disadvantage of this used
process is that th
e production
and growth of algae depends on
the amount of sunlight the
algae’s get. This depends on the
geographic location of the algae
culture. For example the growth
of a algae culture near in Spain
will be greater than the growth of
a algae culture in
Norway.
Another disadvantage is that the
algae cultures need
carbon
dioxide

and

other nutrients
needed for growth and

they
should be kept in

an aqueo
us
environment
. But this
disadvantage is associated with
another advantage. Algae’s can
be used for improvi
ng the quality
of waste water; that is rich on
nutrients (high BOD =
Biochemical oxygen demand

values).

(Biocycle Energy 2009)

Besides all these advantages,
the use of algae has a m
ajor
advantage over traditional
biodiesel feedstock's. From 1
hectare of algae, you could
produce more bio
-
fuels, than
from 1 hectare farm crop
s.
see
"Table
2
: feedstock's”.

(Abayobi
O.Alabi and Martin Tambier 2009;Biocycle
Energy 2009;Fraunhofer Institute for
Interfacial Engineering and Biotechnology IGB
2010;John Ferrell & Valerie Sarisky
-
Reed

2008;Lindsay McGraw 2009;Nick Sazdanoff
2006;Simon Tanner 2009;U.S.Department of
Energy's (NREL) 2010;Wageningen University
2010;Yusuf Chisti 2010)


5
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The "Photoautotrophic
cultivation" of algae's can happen
in two ways, namely as an open
or closed system. The open
system is currently the most
widely used system for the
production of algae, which are
commercially available.

This
system is u
sually constructed as
shallow (+/
-

12cm depth)
channels

called race ways,

Plant source

Biodiesel
(Liter/Ha/y
ear)

soybean

446

Sunflower

952

Rapeseed

1.190

Oil palm

5.950

Algae
(30%
Triacylglycerids)

12.000

Algae
(50%
Triacylglycerids)

98.500

Useful components from algae

Polyunsaturated
fatty acids

Docosahexaenoic
acid (DHA),
Eicosapentaenoic
acid (EPA),
palmitolleic

acid,
oleic acid, α
-
Linolenic
acid and
triacylglycerol

Antioxidants

catalases,
superoxide, and
polyphenols.

Pigments

lutein, chlorophyll,
fucoxanthin and …

Vitamins

Vitamins A, B1, B6,
B12, C, E, Biotin,
nicotinic acid, folic
acid and riboflavin.

Other

proteins, amino
acids, sterols,
antifugal,
antimicrobial and
antiviral agents.

Table
1

useful components from algae

Table 2 Feedstock's

Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

4


(which are +/
-

500m²) in which
the water flows at a low flow rate.


Figure
1

open system: race ways

This is necessary to prevent that
the algae would not settle,
making them less able to
continue photosynthesis

(because of reduced light).

This
system is called open because it
is in contact with the atmosphere,
with the disadvantage

that
evaporation of the water and
this
wat
er needs to be
complemented! A possible
answer

for this c
ould be

waste
water
, coupled to the

advantage
that they immediately

deliver/have a concentration of

nutrients
: nitrogen and
phosphate for example (
see “
3.
What are algae’s
”). But

further
the disadvantages;

there is often
n
o stable temperature (by night
and day difference) and unknown
micro
-
organism can contaminate
the algae culture. Another
drawback is that only a limited
number of algae species raises
such

as can be grown for
example
Chlorella
and

Spirulina
,
O
ther species are grown in
closed systems.

These
disadvantages are not present in
the closed system, or more
specifically "Photobioreactors

(see picture
3
)
.
These are tubes
with a diameter of 38
-
cm
diameter made of transparent
material (glass or plastic), which
in most cases are
horizontal
pipes
stacked as vertical
columns.

They could also be flat
panels (which are also used for
the commercial scale production
)
or bubble columns.

The
preparation of these
photobioreactors as vertical
columns has the advantage that
they obtain a larger contact area
for the algae’s per square meter
of land on which these columns
are placed.
( 2009;Biocycle Energy
2009;John Ferrell & Valerie Sarisky
-
Reed
2008;Nick Sazdanoff 2006;Simon Tanner
2009;Wageningen University 2010)
.

This
closed system as previously
mentioned has the advantage
that there is no contamination of
the algae culture, no evaporation
of water and a stable
temperature. Another advantage
of th
is system is that the algae’s
obtain a higher biomass and
more efficient accumulation of
carbon dioxide (because of no
gas exchange can happen to the
atmosphere).

But this system
also has its drawbacks, for
example these systems are more
expensive than ope
n systems

(lower biomass production than
closed systems)
, there needs to
be a CO
2

injection

(this CO
2

can
be waste of a power plant for
example

and the formed O
2

needs to be disposed. If the
formed O
2

is not been disposed,
the photosynthesis process and
t
he growth of biomass will been
inhibited.

Although this carbon
dioxide for injection can be
obtained from a power plant. For
this reason it is very convenient
that the breeding ground for
algae is placed next to a power
plant.

Next to the
"Photoautotrophic Cultivation"
where the algae need sunlight for
their growth. There is a method,
where the algae's such as
Chlorella pyrenoidosa

and
Scenedesmus obliquus

use a
carbon source (for example
sugar and acetate) to generate
new biom
ass instead using
sunlight . This method is called
"heterotrophic cultivation.

(
2009;70centsagallon 2010;Biocycle Energy
2009;Fraunhofer Institute for In
terfacial
Engineering and Biotechnology IGB 2010;Jeff
Tester & Brian Neltner 2008;John Ferrell &
Valerie Sarisky
-
Reed 2008;Nick Sazdanoff
2006;Simon Tanner 2009;T.J Lundquist et al.
2010;U.S.Department of Energy's (NREL)
2010;Wageningen University 2010;Yus
uf
Chisti 2010)

6
6
.
.


H
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n
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p
p
r
r
o
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s
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o
o
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f


b
b
i
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o
o
-
-
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f
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u
e
e
l
l


w
w
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i
t
t
h
h


a
a
l
l
g
g
a
a
e
e


s
s


o
o
c
c
c
c
u
u
r
r
s
s
?
?


General preparation:

T
he first thing

that has to be
done after the cultivation of
microalgae is the harvesting of
micro algae. This is done by
precipitating and/or flocculation
of the microalgae. This can be
achieved by adding additives
such as alum, lime, salt and ...
which will bind to the

algae. In
addition, the algae can also have
biological flocculation using a co
-

culture of other organisms
which promote
pr
ecipitation
.
Besides sediment
ation
and
precipitation,
you can also collect
t
he algae’s by
using filtration
and/
or centrifugation.
After
having collected the algae
,

the
y

are getting dried, by heating
using an oven or by drying in the
sun to obtain a high biomass
concentration to which the
released water and nutrients are
recycled for another culture.


Note:
macroalgae

must first

be

wa
sh
ed
, then crushed and finally
drying.



Further processing

to bio
-
fuel
:

A)
production of biogas
.

The production of biogas can be
further divided into four biological
and chemical steps, namely
hydrolysis, acidogenesis,
acetogenesis and
methanogenesis.


The remaining biomass consists
mainly of long polymers and thus
must first be broken down into
smaller chains by hydrolysis,
allowing the bacteria to reach the
energy
-
rich areas. Thus, proteins
are broken down into amino
acids and polysaccharides into
simp
le sugars. After the
hydrolysis step

occurs
acidogenesis

with the remaining
components are fermented /
Figure
2

Photobioreactor

Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

5


Ultrasonic extraction:

I n ul t rasoni c ext ract i on,
t her e are
sound
waves (successi ve l ow and hi gh pressure cycl es)


generat ed i n

a

l i qui d medi a. Duri ng t he l ow pressure cycl e
, t here wi l l exi st a
hi gh
i nt ensi t y of ai r bubbl es
f ol l owed by t he hi gh pressure cycl e whi ch
causes t hem t o

i mpl ode. O
nce t hese bubbl es

reach a cert ai n si ze,
t hey wi l l

i mpl ode

(
Thi s
is
called
C
avitation
) creating a high
pressure and speed force. These forces will causes the cell

structure

to break, followed by the release of the cell contents.

Also

a
facilita
te

of these

ultrasound

waves, is that they make it
easier to solve the lipids in the solvents,

so the volume of solvent
is limited.

(Hielscher Ultrasound Technology 2009)


degraded by
acidogenic bacteria
,
into CO
2
,

H
2
S,

ammonia and
volatie fatty acids.


The next step is then
acetogenesis

in which the
components formed in the
acidogenesis step further
processed into acetic acid, CO
2

and H
2

by the
acetogens
bacteria
.


Finally, we arrive at the final step
of “Anaerobic Digestion” namely
methanogenesis.

Here in the
molded products such as
acetate, hydrogen, ammonia,
water and CO
2
, are converted
into methane gas by the
bacteria
"methane
-
forming archaea
(methanogens).

The C
O
2

released from the use of the
methane gas is
/will be

recycled
back into the system of
cultivating a new culture
photosynthetic algae.
For this reason it is very
useful to place algae
culture plant next to a power
plant sites which produced
carbon dioxide

from energy
production, which can be
used for algae
production.
(Anon
2007;A.B.M.Sharif Hossain, Aishah
Salleh, Amru Nasrulhaq Boyce, Partha
chowdhury, & Mohd Naqiuddin 2008;John
Ferrell & Valerie Sarisky
-
Reed 2008;Nick
Sazdanoff 2006)


B) production of biodiesel.

Biodiesel can be produced
throug
h three basic routes for
biodiesel production from oils
and fats. “Base catalyzed
transesterification of the oil”
which is the most used method
these days, because of the high
yields conversion (98%) with
minimal side reaction, low
temperature, short react
ion time
and because of the direct
conversion into biodiesel. Next to
this method there is “Direct acid
catalyzed transesterification of
the oil” and “Conversion of the oil
to its fatty acids and then to
biodiesel”.


The biodiesel production process
from algae’s (is called
transesterfication) occurs by the
following steps:

First they need to
extract the oil fr
om the algae’s,
this is done by
drying the algae
during
20

minutes

at 80°C for
releasing water followed by
mixing hexane with the algae
paste (hexane removes the oil
from the algae). After this the
hexane must be disti
llated from
the mixture, leaving pure algae
oil and the evaporated hexane
will be recycled for another batch
of oil extraction. After this step
the oil will be mixed with catalyst
(KOH) and alcohol (methanol or
ethanol) in a closed system to
prevent losses

of the alcohol.
This reaction mix is kept warm to
speed up the reaction, this
reaction time variants from 1 to 8
hours. During this time the
following reaction will occur:



Once the reaction is complete,
two major products exist: glycerol
and biodiesel. The glycerin
phase is much more dense than
the biodiesel phase and the two
can be gravity separated with
glycerol simply drawn off the
bottom of the settling vessel. This
sett
ling can take +/
-

16 hours.

In some cases, a centrifuge is
used to separate the two
material
s faster. Once
the two phases /
products are
separated, the
excess alcohol in
each phase is
removed by
distillation.
This alcohol
will be recoverd
in most cases an
d be re


used in the next batch.

The glycerol by
-
product
contains unused catalyst and
soaps that are neutralized with
an acid and sent to storage as
crude glycerol.

Once the glycerol is separated
from the biodiesel, the glycerol
would be send to storage

as
crude glycerol. The biodiesel
sometimes needs to be purified
by washing gently with warm
water to remove residual
catalyst, dried, and send to
storage as biodiesel. This
biodiesel is ready for
consumption.
( 2009;70centsagallon
2010;A.B.M.Sharif Hossain, Aishah Salleh,
Amru Nasrulhaq Boyce, Partha chow
dhury, &
Mohd Naqiuddin 2008;Biocycle Energy
2009;Fraunhofer Institute for Interfacial
Engineering and Biotechnology IGB 2010;Jeff
Tester & Brian Neltner 2008;John Ferrell &
Valerie Sarisky
-
Reed 2008;Nick Sazdanoff
2006;Simon Tanner 2009;T.J Lundquist,
N.W
.T.Quinn, & J.R.Benemann
2010;U.S.Department of Energy's (NREL)
Figu
r
e

3

Biodiesel based on algae cycle

Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

6


AlgaePARC (Algae
Production And Research
Centre)


AlgaePARC is an initiative of
Wageningen

UR (University
and Research centre) in the
Netherlands. It is a facility for
research into sustainable and
profitable micro
-
algae
cultivation systems and to
obtain practical experience.
Working on test scale is an
ideal transition from basic
research on
lab scale to
industrial production of algae.
They use seven systems, a
horizontal tubular reactor, a
vertical tubular reactor, a flat
panel and an open pond
which will serve as control.
The other three systems are
photobioreactors (PBRs),
which are chosen
to study the
most fundamental aspects of
a PBR (oxygen, accumulation
an light intensity). Besides
these three major systems
there are 4 to 8 smaller units
(2,5m²) installed to
experiment with algae to
develop the best strains, test
different feedstocks, ne
w
ideas and reactor concepts.
When a good result is
obtained, it can be tested on
a larger scale of 25m.



2010;Wageningen University 2010;Yusuf
Chisti 2010)

7
7
.
.


P
P
o
o
s
s
i
i
t
t
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i
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o
n
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o
o
f
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t
t
h
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a
a
l
l
g
g
a
a
e
e


r
r
e
e
s
s
e
e
a
a
r
r
c
c
h
h
:
:


At October 2010 a report was
released
with the latest research
related to the production of algae
for bio
-
fuel.

It is about a realistic
technology and engineering
assessment of algae biofuel
production.

The first small
industry for the cultivation and
industrial scale production of
microalgae
came about 1953.
Two closed b
ag
-
type
photobioreactors

(PBRs)


set
-
up
on the rooftop of a building. The
microalgae were used for food
production for human
consumption.


Algae production
for lipids was revived when the
US

Department of Energy

(DOE
) Sol
ar E
nergy Research
Institute (
SERI, now NREL,

National Renewable Energy
Laboratory

) initiated the “Aquatic
Species Program” (ASP) in 1980.
It continued until 1996 with the
goal to conduct research on
microalgae oil production for bio
-
fuels.

At 1981 the ASP f
ocused
on

a closed photobioreactor
design and an algae oil
production process that claimed
productivities of over 125 mt
(metric ton) dry biomass/ha
-
y
ea
r,
with a high oil content. An
independent analysis at 1982
from the DOE, found no basis for
such claims

and an economic
cost study demonstrated that
PBR’s had no merit for biofuels
production. John Benemann
carried out a more detailed
techno
-
economic analysis of an
open raceway pond process for
algae oil production, based on an
assumed algae biomass
product
ivity of 82 mt/ha
-
yr and an
oil content of 40%. Achieving the
projected productivities and oil
content became an important
purpose of the ASP.

The ASP
was finally closed in 1996.

Over the past five years there
has been an intrest in microalgae
for
biofuel production. Especially
algae oil production.
The
attention was due to the
increasingly search for an
inexpensive, secure an plentiful
replacement for oil and by fears
of global warming.



Earlier this
year, the DOE
founded a $44 million (33 million
euros) three
-
year program
. The
Department of Defense funded
two algae projects to develop
technology capable of producing
algae oil for less than $3/gallon
(3,79 liters) by 2012.

Unfo
rtunatly, much of the current
interest in algae oilproduction is
based on a misunderstanding of
the scientific underpinnings of
this technology. For example,
although some algae strains can
accumulate large quantities of
algae oil as triglycerides under
c
ertain conditions, They do so
only in low numbers and
productivity.
This would have no
practical application. “Thus,
development of this technology is
not likely to be a sprint to the
finish line, but, rather, a long and
difficult march, with high risks
an
d uncertain outcomes
.”


8
8
.
.


M
M
a
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a
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a
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e


t
t
o
o


o
o
b
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a
a
i
i
n
n


a
a


h
h
i
i
g
g
h
h
e
e
r
r


p
p
r
r
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f
f
i
i
t
t
a
a
b
b
i
i
l
l
i
i
t
t
y
y


Algae’s could be genetic
modified for obtaining a higher
yield of biomass or lipid content.
For obtaining a higher biomass,
they will use a algae species that
grows at a high
rate. This
manipulation is specific for
making biogas out of the algae’s.
The lipids will be specific
modified for obtaining more
lipids, so they could produce
more bio
-
diesel from this algae
culture.

They can do this by
increasing the number of
chloroplas
ts in the algae by
genetic engineering, or modify
the metabolism (manipulation of
the production of enzymes for
lipid production) which would
increase the efficiency of
Figure

4

First algae mass culture

experiments on a rooftop at MIT
(Burlew,1953)

Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

7


Alginate
:
Used
in food industry
as a thickener or
in dentistry for
printing of the
teeth.

Are algae profitable?

Nowadays, the
production of
algae isn’t profitable because
the investment cost for growth
installations are high, these
reactors consume much
energy and algae are grow
diluted stretch conditions. It
means that more than 1000l of
water is needed to grow 1kg
of algae. Thi
s makes the costs
of harvesting algae very high.


photosynthesis or less sensitive
to oxygen concentration causing
no inhibition of photo
synthesis
occurs. We can also potentially
increase the growth rate.


Most of the work to
improve/increase in yield is
mainly studied by selecting
species (strain improvement) and
adjusting the cultivation
techniques. Genetic engineering
gets more attention

only recently
begun to manipulate algae. The
use of genetic modified
organisms is only accepted in a
closed system by the European
union so there will be no junction
with non manipulated organisms
in the environment. The public
opinion is against the
mani
pulation of organisms
because they don’t trust it so
much.


As already mentioned, we can
increase the efficiency of
photosynthesis. However, the
damage can
-
Excessive light
photo systems and to trigger cell
was photo
-
prot
ective
Mechanisms That must or
r
adia
ted energy is captured as
heat or fluorescence. In the
interest of engineering a strain
microalgae to effectively capture
light energy, researches focused
on Reducing the number of light
-
harvesting antenna complexes
(LHCs) Which capture sunlight
and transf
er the derived energy
to drive photosynthesis
(process).


For example Mussgnug et al
(2007) Reported that they
successful reduced the
regulation of LHCs in
Chlamydomonas reinhardtii.

The
photosynthetic efficiency and
light penetration improved in
liquid cu
lture. The LHC mutation
offers a higher efficiently
conversion of solar energy to
biomass. Currently they only
modified the genes of the algae
to create better lipids for the
biofuel production, they don’t
introduced new genes in the
algae yet to make the
algae
better for bio fuel production. The
introducing of new genes would
have a very low possibility of
doing anything bad to the
environment.

( 2009;John Ferrell &
Valerie Sarisky
-
Reed 2008;T.J Lundquist,
N.W.T.Quinn, & J.R.Benemann
2010;Wageningen University 2010)

9
9
.
.


A
A
p
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w
w
i
i
t
t
h
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t
t
h
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e
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b
b
i
i
o
o
-
-
e
e
n
n
e
e
r
r
g
g
y
y


f
f
i
i
e
e
l
l
d
d


Algae Food&Fuel
is a
company
that has just been booted from
the initiative of the company’s
BioSoil, Tendris and Solarix. The
company is located in Hallum,
this is a village in the province of
Friesland in the Netherlands.
They are specialized in the
enabling of industrial pro
duction
of microalgae for food and fuel.
Bio
-
fuel companies, can rely on
Algae Food&Fuel’s technology
for the production of algae
feedstock with high triglyceride
contents, yet with minimal water
processing. We asked about their
opinion of the production o
f algae
and its future in an interview

with
Arthur Kroon
.



Has the development of
the algae industry
already progressed far

Mr.
Kroon
?


Yes and no:
algae are a mature
industry
as you
look at
health
foods
made of
Spirulina
and
Chlorella, or specialty products
like alginate or agar
-
agar.

But the
primary production of algae is
small. In tons,
the algae industry
is a dwarf.
The annual production
is about 3000 tons of Spirulina

and 2000 tons of Chlorella. 3 little
farmers with 100 Hectares of
maize and potatoes make
already more biomass. For
reference: An average soybean
plantation is 1000 hectares and
the largest are 50 000 hectares.




Are there still new
developments?

Yes, th
is field is developing very
fast the last 3 years. that is
because of rising fuel prices,
growing global population and
the knowledge that fossil fuels
and phosphate are consumed
faster than is produced.



What do you think of
genetic modification on
algae
for biofuel
production?

It is inevitable that GMA will be
used in the future. We use none
of that now,
we keep our first
engaged in farming and
downstream processing
. GMA
making is a time consuming
process that only specialized
laboratories can perform.
We
don’t have laboratories like that.


Figure
5

Logo Algae Food&Fuel

Fig
ur
e

6

continue
s

system
s

of the company

Production of algae coupled to anaerobic digestion in a closed vessel system for bio
-
fuel production
.

8


Solazyme


Solazyme is
a company

founded in 2003 and situated
in South San Francisco. They
produce oils and biomaterials
from algae in standard
fermentation facilities.



Algae’s in the desert ?

Algae can be grown well in
desert regions. In the desert
there is plenty of sunshine,
needed for the
photosynthesis, and access
to water unusable for
drinking, for instance
seawater. This m
eans that
unproductive lands can be
useful.





Is the cultivation of algae
for biofuel production
profitable?

No, at this time investment costs
are not to recover in a
reasonable depreciation period
on fuel sales alone. A cheap and
scalable
biorefinery

model with
multiple
revenue streams must
be found. For example, oil is so
profitable because there is an
application from the first to the
last drop. asphalt as the lowest
value, jet fuel, chemical
substances and fine chemicals
as the highest value.





Is it for example as
profitable as the
production of rapeseed
oil for biofuel?

Biodiesel from rapeseed is not
profitable. Biodiesel plants are
almost all closed in Europe due
to the high fee charged by the
U.S. to biodiesel producers.
They
sold their produ
cts well in
Europe.





Are there many
companies who
purchase algae to biofuel
co
-
produce?

No, companies do not buy much
algae witch grow on sunlight.
Solazyme and saphire

in the U.S.
for example, sell research
quantities of oil from algae fed
with sugars on defense. but for
the military the "normal"
economic laws does not count





Is there already an
significant use of biofuels
produced by algae?

No, there isn’t.




How long does it take
before a batch is
finished?

We grow in chemo state and
turbid state, or continuous
systems. At this time we harvest
about 50 kg dry matter/day/ha. It
is November now, The water is
three degrees and still we
harvest algae.
In the summer, it
obviously goes better.





How many algae are

grown each year ?

This is the first season that I
have operate this system.
after one year, I know more
about it. But I estimate that
between 10 and 20 tones of dry
seaweed per hectare per year
can be grown. The percentage of
lipids can be increased

but not as
easy as the literature prescribes.








C
C
O
O
N
N
C
C
L
L
U
U
S
S
I
I
O
O
N
N




When you read
all
the

different
literature about bio
-
fuel production

from algae;

everything seems so
easy and perfect. But nothing is
further from the truth. The
production of algae fuel is applied
but
in some cases it seems to be

not
profitable.
But s
ome countries like
the U.S.
, Belgium(SBAE) and the
Netherlands(Algae Food&Fuel) stil
l
have applied the
technology/cultivation with success
to make a
profitable

living. In the
cases

they

also

invest in
research so
this businesses can grow. For those
companies that supported I do see a
future. Other companies will have
difficulties,

because

not enough
people realize
what's happening in
the world. We

think the common
man is not quite ready for the use of
bio
-
fuel.

To be profitable the
companies need to produce algae
for other purposes such as food or
feed.


In our viewpoint, we say “Yes to
application of algae cultivation to
produce bio
-
fuels and other

products!”.
Production of algae coupled to anaerobic

digestion in a closed vessel system for bio
-
fuel production
.


1

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1
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0
.
.


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References


Biodiesel Production and Quality. 26
-
5
-
2007. America, National Biodiesel Board.

Ref Type: Online Source

Microalgae: A promising feedstock for biodiesel. Microalgae: A promising feedstock for biodiesel , 1. 2009.
African Journal of Microbiology Research.


Ref Type: Journal (Full)

70centsagallon 2010,
Algae Photo Bioreactors
, Biofuel Technologies, Sarasota,Florida.

A.B.M.Sharif Hossain, Aishah Salleh, Amru Nasrulhaq Boyce, Partha chowdhury, & Mohd Naqiuddin. Biodiesel
fuel Production from Algae us Renewabl
e Energy. American Journal of Biochemistry and Biotechnology , 250
-
254. 2008. University of Malaya,Maleysia, 2008 Science Publications.

Ref Type: Journal (Full)

Abayobi O.Alabi & Martin Tambier. Microalgae technologies and processes for biofuelsbioenergy

production in
Britisch Columbia. 1
-
88. 14
-
1
-
2009. Columbia, University of Manitoba.

Ref Type: Online Source

Arno van 't Hoog, Marian van Opstal, Arthur van Zuylen, Gerart Stout, & Prof.Dr.Ir.Bert Weckhuysen.
Biomassa.
Chemische feitelijkheden . 2008. Chemische Feitelijkheden.

Ref Type: Magazine Article

Biocycle Energy 2009,
Cultivating Algae in Wastewater for Biofuel
, Biocycle Energy.

Biofields
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