lesson 6 - biomara 6 - using algae to produce biofuel.pdf · lesson six. page 105 lesson 6: how to...

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Lesson 6

From lesson 5 you have discovered that there are many uses for algae. You also have discovered that algae can be used to produce biofuels. Biofuels are fuels that are made from biomass.Biomass is material from living or recently living organisms. Some common examples of biomass are algae, grass and wood. Biomass can be used to make biofuels. There are three common types of transport biofuels in Europe; bioethanol, biodiesel and biogas. Bioethanol is mixed with petrol, biodiesel is mixed with diesel and biogas (methane) can be used to fuel specially adapted vehicles. These three types

of biofuel can be produced from algae.

BiofuelAll Biofuels are made from biomass. These biofuels can all be produced from algae.

In this section you will learn how all three different biofuels are made using algae.

BiodieselBiodiesel can be made from oils within the algae. As we learned in a previous lesson, micro-algae contains oil within its cell. This oil can be used to make biodiesel. There are different varieties of microalgae which contain oil. The scientists that make the biodiesel try to identify the species of microalgae that have the most oil within their cells and also the microalgae that grows best within its environ-ment. Some microalgae have lots of oil, but are very fragile and so will not grow well at large scales. Once grown, the oil is removed from the microalgae using chemicals or by squeezing oil out of the cells using scientific equipment. Then the oil is used as an ingredient in biodiesel. This oil is changed chemically from plant oil to biodiesel. The finished product can be used on its own as pure biodiesel but is normally mixed with ordinary diesel and used directly in cars. There is biodiesel in most mineral diesel on sale in Europe but it makes up less than 5% unless otherwise noted.

Content Section - How Algae can be used to produce Biofuel.

Lesson Six. 03

Lesson Six. Page 104

BioethanolBioethanol is used in petrol. Ethanol is better known as alcohol. The word “bioethanol” means ethanol that can be made from biomass mainly for transport use. Macroalgae can be used to make bioethanol. Macroalgae that contain a high amount of sugar are used in the production of bioethanol. The macroalgae are cut and treated to free up the sugars within the algae. These sugars decom-pose to a simple sugar called “glucose”. The macroalgae is now a “feedstock” for the next step.

Yeast is then added to the process. During this time there is a chemical reaction produced by the yeast called “fermentation”. Fermentation is when the yeast uses glucose and produces ethanol and other components. The ethanol is then separated from the other components by heating it up until it boils and then cooling the vapours. This is called distillation. The bioetha-nol undergoes a further filtering process to remove water so it can then be used as an ingredient with petrol.

BiogasBiogas is produced naturally from the break-down of organic material. The main constitutent in biogas is methane gas. Macroal-gae can form biogas because of its high sugar content. It is washed, mashed up and treated and then becomes the “feedstock”. The feedstock then enters big tanks. At this stage special micro-organisms called “anaerobes” are added when conditions are correct. These micro-organisms are special because they live and work without oxygen. They use the feedstock for their food and there are a series of chemical reactions which happen in this environment called “Anaerobic Digestion”. When the feedstock undergoes anaerobic digestion by the micro-organisms they produce methane gas. Anaerobic Digestion literally means eating without oxygen. For the micro-organisms to

survive and the anaerobic digestion to produce gas the environment must be correct. The environment consists of no oxygen (air), correct temperature and acidity.The anaerobic digestion results in the production of meth-ane gas and carbon dioxide (C02). They can be produced in a 50:50 ratio but normally there is a little more methane than biogas. The biogas can then be burned directly in an engine or a cooker or upgraded for use in car engines or for generating electricity, The remaining sludge in the anaerobic digester can be used as a fertiliser.

Advantages of using algae as biofuelBiofuels have many advantages as sources of renewable energy. Algae occur naturally, grow quickly and produce oxygen by photosynthe-sis. Macroalgae don’t grow on land and so do not compete with land based plants which are normally used for food. Therefore macroalgal biofuels have little effect on farms or food supplies. Biofuels reduce air pollution. They are described as “carbon neutral”. This means that carbon dioxide is used by algae and plants from the atmosphere during photosynthesis to make their own food but the same amount of carbon dioxide is also returned to the atmosphere when used as a biofuel. This means that addi-tional carbon dioxide is not being added to the atmosphere that is not ‘fixed’ again in the near future in macroalgae again.

As we know that burning fossil fuels such as petrol or coal increase pollution and increasescarbon dioxide. Carbon dioxide is a greenhouse gas and governments throughout the world would like us to reduce the amount of green-houses gases and pollution. Using biofuels could help to reduce the amount carbon dioxide in the atmosphere.


Lesson 6: How to use algae as biofuel.

Brief Summary Aim: The aim of this lesson is to show how algae can be used as biofuel and briefly illustrate the 3 different methods of production of biogas, biodiesel and bioethanol.

Biofuels - are made from biomass. Biomass is material from living or recently living or-ganisms. Examples of biomass are grass, wood and algae. Both macroalgae and microalgae are involved in the production of biofuel. The word biofuel means fuel that is made from biomass. Biofuel is a term used to describe biodiesel, bioethanol which is used in petrol and methane gas which is found in biogas.

Biodiesel - Microalgae are involved in the production of biodiesel. Microalgae are chosen for the production of biofuel based on their oil content. The oil inside the microalgae is removed from algae by chemical means or either squeezed out. The oil is collected and changed chemically and is then used as an ingredient in biodiesel.

Bioethanol – Bioethanol is an ingredient used in the production of petrol. Macroalgae that contain a lot of sugar are chosen. Macroalgae are cut, mashed and treated. The macroalgae now appear as sludge and is called feedstock.Other micro-organisms called Yeast are added at this stage. Yeast uses the feedstock as food and breaks down the feedstock into ethanol and other components. This process is called fermentation. Ethanol is separated from the other components and then the ethanol is used in petrol.

Biogas – Methane is the main ingredient in the production of biogas. Methane gas can be produced by using macroalgae. The macroalgae must have a high sugar content. Macroalgae are cut and mashed. Micro-organisms convert the natural sugars in macroalgae into glucose. The macroalgae now appear as sludge and is called feedstock. The feedstock will go into a big tank and special micro-organisms called anaerobes are added. These micro-organisms are special because they don’t need oxygen to survive. They work without oxygen(air). They also need an environment that has the correct temperature and acidity. When conditions are correct the special micro-organisms perform a series of reactions called anaerobic digestion. Within this environment methane and other gases are produced. The methane gas is separated and used as biogas.

Biofuel is better for the environment because biomass is easily accessible. Biomass in-cludes grass and algae which absorbs carbon dioxide during photosynthesis. The biomass is then used to make biofuel.


Learning Outcomes: ► Describe how algae is used for energy and transport. ► Explain the three procedures of producing biodiesel, bioethanol and biogas. ► Explain why it is better to use biofuel than ordinary diesel, gas or petrol.

Introduction: Recall from Lesson 5 that one of the uses of algae is for fuel.Explain biomass. Explain how natural resources such as algae can be used for biofuel production. Describe briefly that there are three different methods for producing biofuels by simply explaining concepts such as Fermentation and Anaerobic Digestion. Use visual aids if neccesary.

Activity:Activity 1. - Explanation by movement about how biofuel (Biodiesel, bioethanol and biogas) is produced.

Final Activity: ► Teacher revises the main learning points. ► Teacher may ask pupils to complete Activity 2- Steps to produce Biogas, Steps to produce Bioethanol and Steps to produce Biodiesel.

► Ask class how algae benefits the environment.

Vocabulary: fermentation, anaerobic digestion, glucose, yeast and biomass.


Steps to produce Biodiesel.

1. Microalgae cells are specially grown and selected for their oil content. They contain oil inside their cells.

Microalgae

Oil

Biodiesel

2. The oil is taken out of the microalgae by the use of chemicals. The oil may also be squeezed out of the microalgae cells by scientific equipment.

3. The oil is then changed chemically so it can be used as biodiesel.


1. Macroalgae is chosen because it has a high sugar content.

4. The ethanol is separated from the other components and filtered. The bioethanol can now be used with petrol.

3. Micro-organisms called Yeast are added to the feed-stock mixture in a big tank. The feedstock is changed by the yeast to ethanol and other components. This process is called fermentation.

2. The macroalgae is cut up and treated.It appears like sludge and it is now called feedstock.

Steps to produce Bioethanol.

Macroalgae

Feedstock

Yeast

Tank Fermentation

SeparationBioethanol


1. Biogas can be made using macroalgae. The macroalgae chosen must contain a high amount of sugars.

2. The macroalgae is then washed and cut up. Micro-organisms help to decompose the macroalgae. The substance is now called feedstock.

3. The next step is called Anaerobic Digestion. It takes place in big tanks. Special micro-organisms are added. These micro-organisms are called anaerobes and can breakdown the macroalgae with-out oxygen. They need their environment to be warm, acidic and must contain no oxygen (air).The mixture undergoes a series of reactions thanks to the micro-organisms. Methane gas is produced at the end of this process.

4. Methane gas is the main ingredient of biogas which can be used as fuel.

Steps to produce Biogas

Macroalgae

Feedstock

Anerobic Digestion

Biogas


Literacy and EnglishListening and talkingfinding and using information

Writing, processes, creating texts

SciencesPlanet Earth energy sources and sustainability

Expressive artsDrama

Literacy and English Listening and talking

Writing,creating text

SciencePlanet Earth

Expressive ArtsDrama

As I listen or watch, I can identify and discuss the purpose, key words and main ideas of the text and use this information for a specific purpose. LIT 1-04a

I can convey information, describe events or processes, share my opinions or persuade my reader in different ways. LIT 1-28a / LIT 1-29a

I am aware of different types of energy around me and can show their importance to everyday life and my survival. SCN 1-04a

I enjoy creating, choosing and accepting roles, using movement, expression and voice. EXA 1-12a

As I listen or watch, I can identify and discuss the pur-pose, main ideas and supporting detail contained within the text, and use this information for different purposes. LIT 2-04aI can convey information, describe events, explain pro-cesses or combine ideas in different ways. LIT 2-28a

Through exploring non-renewable energy sources, I can describe how they are used in Scotland today and express an informed view on the implications for their future use. SCN 2-04b

I can create, adapt and sustain different roles, experi-menting with movement, expression and voice and using theatre arts technology. EXA 2-12a

ScotlandCurriculum for Excellence

Level 1

Level 2

Skills: Comprehend, move, question and describe.

Curriculum Links


EnglishOral Language, developing cognitive abilities through oral language

Writing, developing cognitive abilities through language

Social Environmental and Scientific Education (SESE)ScienceEnvironmental awareness and care, caring for my locality

DramaDrama to explore feelings, knowledge and ideas, leading to understandings, reflecting on drama

EnglishWriting, developing cognitive abilities through language

Reading, receptiveness to language

Social Environmental and Sci-entific Education (SESE)ScienceEnvironmental awareness and care, caring for my locality

DramaDrama to explore feelings, knowledge and ideas, leading to understandings, reflecting on drama

Give a description, recount a narrative or describe a process and answer questions about it.

Write a simple sentence and add words to it to extend its meaning.

Realise that there is both an individual and a community responsibility for taking care of the environment.

Experience, through drama, the relationships between the story, theme and life experience.

Third Class, Fourth Class and Fifth Class

Read a story and write it in his/her own words.

Understand the relationship between text and illustration.

Become aware of the importance of the Earth’s renewable and non-renewable resources.

Learn through drama, the relationship between the story, theme and life experience.

Skills: Drama, observe, read and comprehend.

IrelandNational Council of Curriculum and Assessment (NCCA)

First Class, Second Class


Language and LiteracyTalking and listening

Reading

Writing

The World Around UsChange over time

The ArtsDrama

Language and Literacy Talking and listening

Reading

Writing

The World Around UsChange over time

The ArtsDrama

Listen to, interpret and retell, with some supporting detail a range of oral and written texts.

Explore opinions and give reasons based on what they have read.Spell correctly a range of familiar, important and regularly occurring words.

Positive change and how we have a responsibility to make an active contribution.

Develop their understanding of the world by engaging in a range of creative and imaginative role situations.

Describe and talk about real and imaginary situations.

Represent their understanding of texts in a range of ways, including visual, oral and dramatic.

Express thoughts, feelings and opinions in imaginative and factual writing.

The effects of positive and negative changes globally and how we contribute to some of these changes.

Develop their understanding of the world by engaging in a range of creative and imaginative role play situations.

Northern IrelandCouncil for Curriculum Examination and Assessment (CCEA)

Key Stage 1

Key Stage 2

Skills: Question, drama, comprehend and working together.

Lesson Six. 3

Activity 1-Explanation by movement about how biofuel (Biodiesel, bioethanol and biogas) is produced.

This activity will explain how bioethanol, biodiesel, and biogas is produced by the movement of pupils. It will take place in the classroom or in an open space. Pupils will rep-resent each stage of the process. They will represent micro-organisms, sugar, glucose, yeast, macroalgae, other components, oil and other ingredients involved in the production of biofuels. The pupils should also be provided with labels (and some images) to name the group which they represent. They must work together and provide the answers at all stages.The teacher will follow the diagrams of bioethanol, biodiesel and biogas production from that which are supplied in the materials on page 107, 108 and 109. The teacher may use the images provided on page 117, 119 and 121. The teacher can cut the individual images and stick them up on the board as the class explains the production process of each fuel. There are a few images that are not included so the pupils must use their imagination. The teacher may chose to explain either “production of biodiesel” or “production of biogas” or “production of bioethanol”. Read the instructions before completing the activity.Production of BiodieselChoose 3 groups of pupils.Choose a big group representing “microalgae”, choose a smaller group respresenting “oil” and another group representing “other ingredients in biodiesel”Label each group. (3 stages )

1. Teacher asks pupils about first stage of biodiesel production.There is oil within the cell of the microalgae.

Choose the “microalgae” group and the “oil” group.Place pupils representing microalgae around pupils representing oil within microalgae.Teacher will use the image of microalgae on page 117 to explain the first stage of diagram on board.

2. Teacher asks pupils to describe next stage.The oil within the microalgae is removed by chemicals or either squeezed by machines to release the oil.

The pupils representing the oil within the microalgae will move onto stage 2.Teacher will use the image of the oil provided to explain this stage on the board.

3. Teacher will ask pupils to describe the next stage.The oil from microalgae is changed chemically and then it mixes with other ingredients to form biodiesel.

The group representing oil within microalgae will move onto stage 3 and they will join the group representing “other ingredients in biodiesel”.

Activity Section –


Teacher will use the image of the biodiesel pump at this stage on the board.

Production of BioethanolPupils must be divided into 1 large group representing “macroalgae”. The “macroalgae” group changes to “ethanol”, “other components” as they go along the production process.2 smaller groups representing “Yeast”, “other ingredients in petrol”Label each group. (4 stages)

1. Teacher will ask pupils to describe the first stage.Macroalgae is choosen for its high sugar content.

Choose a large group to represent “macroalgae”. Teacher will use the image of macroalgae at this stage on the board.

2. Teacher will ask pupils to describe the next stage.The macroalgae is cut and washed and turns into sludge. The sludge-like material is now called feedstock.

Pupils representing “macroalgae” group from stage 1 move onto stage 2. Explain to the pupils that the macroalgae are washed, cut and mashed up. The “macroal-gae” group is now labelled “feedstock”. Teacher will use the image of feedstock to explain what happens at this stage. Place the image on the board.

3. Teacher will ask pupils to describe the next stage.

The feedstock is placed in a tank and micro-organisms called Yeast are added. Yeast breaks down the feedstock and produces ethanol and other components. This process is called Fermentation. As the ethanol concentration increases the yeast micro-organisms die.

Pupils representing the “feedstock” move to stage 3. A group of pupils are chosen to represent “Yeast” micro-organisms. They are labelled and enter stage 3. The “yeast” changes the “feedstock” group into “ethanol” and “other components”. Take some of the pupils from the “feedstock” group and label them as “ethanol” and take other pupils from the “feedstock” group and label them as “other components”.The “yeast” micro-organisms eventually die as there is too much ethanol produced. The pupils representing the yeast group lie on the floor respresenting death .Teacher will use the images of Yeast, Tank and Fermentation to explain this stage. Put all images on the the board.

4. Teacher will ask pupils to describe the next stage.Ethanol is separated from other components. Ethanol is cleaned to become pure ethanol. The bioethanol (which is ethanol made from biomass) becomes an important ingredient in petrol.The pupils representing “ethanol” are separated from “other components”. The pupils representing “ethanol” move onto to stage 4.


Choose another group of pupils representing “other ingredients in petrol”.Mix the pupils representing “ethanol” with the pupils representing “other ingredients in petrol” together.Teacher will use the seperation and bioethanol images to explain this concept. Place these images on the board.

Production of Biogas Pupils must be divided into 1 large group representing “macroaglae”. The group representing “macroalgae” will change throughout the production process and will be labelled “sugars”, “glucose”, “feedstock”, “methane gas”, “fertilizer”..3 smaller groups representing “micro-organisms”, “micro-organisms who work without oxygen” and “other ingredients in biogas”Label each group. (4 stages)

1. Teacher will ask pupils to describe the first stage.The macroalgae that is chosen must be high in sugar content.

Choose a group of pupils representing “macroalgae”.Teacher will the image of macroalgae and place it on the board.

2. Teacher will ask pupils to describe the next stageMacroalgae is washed, cut and mashed. Micro-organisms help to break down the sugar content into simple sugars called glucose. The environment changes, this due to moisture content, acidity and temperature change cause micro-organisms to then die. The macroalgae over time turn into sludge and this is called feedstock.

Move pupils representing “macroalgae” to stage 2. Choose some pupils within this group to represent sugars. Label them “sugars”. Get the sugar group to hold hands. Introduce a new group and label them as “micro-organisms”. The “micro-organisms” group will unlock the hands of the sugar group. This represents the micro-organisms breaking the sugar into simple sugars called glucose. Label the sugar group as “glucose”.The “glucose” group and the remaining “macroalgae” pupils all become one group and will be labelled as “feedstock”

The group representing “micro-organisms” will lie on the floor as the micro-organisms will die due to the environmental conditions.Teacher will use the image of feedstock to explain this stage. Place the image on the board.

3. Teacher will ask pupils to describe the next stageAll of the feedstock will enter big tanks called anaerobic digesters where the environment and temperature is controlled. In this environment there is no oxygen. Special micro-organisms are added. This environment is ideal for producing methane gas.


Pupils representing the “feedstock” all enter the tanks at stage 3. Choose a group of pupils who represents special micro-organisms who can work without oxygen. Label them as “microorganisms who work without oxygen”.Mix the groups labelled “microorganism who can work without oxygen” and the “feed-stock” together.Teacher will use the image of Anaerobic Digester to explain this stage. Place the image on the board.

4. Teacher will ask pupils to describe the next stage.In the Anaerobic Digester a number of chemical reactions take place. The micro-organisms that work without oxygen use the feedstock as food and break them down. Over time methane gas and other gases are produced. The remaining feedstock are converted to fertilizer. Fertilizer will help grass to grow. The micro-organisms will die as there is too much gas produced.

Move both groups to the stage 4.

This will include the group labelled “feedstock”and “microorganisms who work without oxygen”.Get the “micro-organisms who work without oxygen” to separate from the “feedstock” representing the fact that the micro-organisms use the feedstock as food.Take some members of the “feedstock” group and label them as “methane gas”. Some of the micro-organisms die off at the end of the process. The group representing “microorganisms who work without oxygen” lie down on the floor to represent that they are now dead.

The “methane gas” group separate from the feedstock. The rest of the “feedstock” group are then labelled “fertilizer”.

Choose another group and label them “other ingredients used in biogas”. Mix the “methane gas” group with the group labelled “other ingredients used in biogas”. This group now becomes “biogas” as the main ingredient in biogas is methane gas.Methane gas is the main gas used in biogas. Biogas is a type of biofuel.Teacher will use the image of biogas to explain this stage. Place the image on the board. the diagram on the board.

Microalgae Oil

Biodiesel/ Biogas

MacroalgaeLess

on S

ix.

Page

117

Feedstock Tank

Fermentation

Yeast

Less

on S

ix.

Page

119

BioethanolAnaerobic Digestion

Less

on S

ix.

Page

121


Activity 2 – Steps to produce Biodiesel.

1.

2.

3.

Name

Microalgae

Oil

Biodiesel


3.

4.

2.

1.

Activity 2 – Steps to produce Bioethanol.

Name

Macroalgae

Feedstock

Yeast

TankFermentation

SeperationBioethanol


3.

4.

2.

1.

Activity 2 – Steps to produce Biogas.

Name

Macroalgae

Feedstock

Anaerobic Digestion

Biogas


Activity 3 - What am I?

I am a fuel that can be used in cars or to generate heat in houses or generate electricity. The main component involved is methane and carbon dioxide. What am I?

My name is used to describe a group of environmentally friendly fuels. I can be described as a renewable fuel where my raw products can be grown naturally and can be used for other purposes. I am not a fossil fuel. What am I?

I am a fuel. I am produced by microalgae resulting in oil production. I can be blended with other normal fuel. What am I?

I am a fuel. I use micro-organisms called yeast to breakdown the feedstock andproduce ethanol. What am I?

Name


Questions

1. What is the one common name for biodiesel, biogas and bioethanol produced by algae?

2. Name some examples of biomass?

3. How is oil taken out of microalgae?

4. What is the name of the substance when sugars are broken down (decomposed)?

5. What is the name of the micro-organisms involved in fermentation?

6. What do you call the micro-organisms that do not require oxygen?

7. What is the name of the main gas in biogas?

8. When the process of biogas production is finished, how can the leftover feedstock be used?

9. Apart from fuel, what are the other uses of biogas?

10. Where is biogas made?


Answers

Activity 2 Steps to produce Biodiesel 1. Microalgae cells are specially grown and selected for their oil content.

2. The oil is taken out of the microalgae by the use of chemicals. The oil may also be squeezed out of the microalgae cells.

3. The oil is then changed chemically so it can be used as biodiesel.

Steps to produce Bioethanol 1. Macroalgae is chosen because it has a high sugar content such as Laminaria digitata (Oarweed) or Saccharina latissima (Sea belt).

2. The macroalgae is cut up and treated.It appears like sludge and the substance is now called feedstock.

3. Micro-organisms called yeast are added to the mixture in a big tank. The feedstock is changed by the yeast to ethanol and other components. This process is called fermentation.

4. The ethanol is seperated from the other components and filtered. This can now be used with petrol.

Steps to produce Biogas 1. Biogas can be made using macroalgae. The algae chosen must contain a high amount of sugars.

2. The macroalgae is then washed and cut up. Micro-organisms help to decompose the macroalgae. They help to break down the sugars. This makes it easier to produce biogas. The substance is now called feedstock.

3. The next step is called Anerobic Digestion. It takes place in big tanks. Special micro-organisms are added. They can breakdown the macroalgae at this stage without oxygen. They need their environment to be warm, acidic and free from oxygen(air). The mixture undergoes a series of reactions thanks to the special micro-organisms called anaerobes. Methane gas is produced at the end of this process.

4. Methane gas is the main ingredient of biogas which can be used as fuel.


Activity 3 - What am I? I am a fuel that can be used in cars or to generate heat in houses or generate electricity. The main component involved is methane and carbon dioxide. What am I? Answer: Biogas.

My name is used to describe a group of environmentally friendly fuels. I can be described as a renewable fuel where my raw products can be grown naturally and can be used for other purposes. I am not a fossil fuel. What am I?Answer: Biofuel.

I am a fuel. I am produced by microalgae resulting in oil production. I can be blended with other normal fuel. What am I?Answer: Biodiesel.

I am a fuel. I use micro-organisms called yeast to breakdown the feedstock and can produce ethanol. What am I?Answer: Bioethanol.

Questions1. What is the one common name for biodiesel, biogas and bioethanol produced by algae? Answer: Biofuels are known as biodiesel, biogas and bioethanol.

2. Name some examples of biomass?Answer: Grass, algae, and wood.

3. How is oil taken out of microalgae?Answer: Oil can be squeezed out of microalgae by using special machines or chemicals.

4. What is the name of the substance when sugars are broken down(decomposed)?Answer: Glucose.

5. What is the name of the micro-organisms involved in fermentation?Answer: Yeast.

6. What do you call the micro-organisms that do not require oxygen?Answer: Anaerobic micro-organisms are called “anaerobes.

7. What is the name of the main gas in biogas?Answer: Methane gas.

8. When the process of biogas production is finished, how can the leftover feedstock be used?Answer: It can be used as fertilizer.

9. Apart from fuel, what are the other uses of biogas?Answer: Heating and electricity.

10. Where is biogas made?Answer: In big tanks called Anaerobic Digesters.

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