6D: Biofuel Fermentation

Question 1

Non-renewable

Answer 1

Non-renewable: refers to resources that is replenished at a slower rate than it is being used

- Fossil fuel resources can eventually run out

Question 2

Renewable

Answer 2

Renewable: a resource that can typically be replenished at a faster rate(or the same) than it is being used

    - Biofuels are unlikely to run out

Question 3

Fossil Fuels

Answer 3

Fossil Fuels: Fuels that formed over tens of millions of years from the remains of dead organic material

- Considered non renewable energy, there is a finite amount
- Burning fossil fuels mixes the carbon released with oxygen in the air creating CO2
- Negative impacts of burning fossil fuels include biodiversity loss, alterations to ecosystems and climate change

E.g. Coal, oil

Question 4

How Fossil Fuels are Made

Answer 4

• They are formed from decomposing organic material(i.e. Plant matter) which has fossilised over millions of years
  - When plants die, they often retain a lot of carbon and so after millions of years, they will have been buried deep under the earth where the pressure and heat will have turned the high carbon plant into different fossil fuels

Question 5

Biomass

Answer 5

organic material which can be sourced from many industries including farming, forestry and food manufacturing

E.g. Plants, animals by products, biological waste

Question 6

Biofuel

Answer 6

fuel created from organic material known as biomass

- E.g. bioethanol, biogas, and biodiesel
- Considered renewable and carbon neutral meaning they are good for the environment

Question 7

Carbon Neutral

Answer 7

a state in which there is no net release of CO2 into the atmosphere

(CO2 absorbed = CO2 emitted)

Question 8

Hydrolisis

Answer 8

a chemical reaction in which water is used to break down the chemical bonds of a substance

Question 9

Bioethanol

Answer 9

a type of biofuel that is produced via the anaerobic fermentation of plants such as sugarcane or corn

Question 10

Deconstruction stage of creating Bioethanol

Answer 10

1. Deconstruction:
   
   • The biomass is treated to help increase its surface area: volume ratio enough to help increase the efficiency of the fermentation process
   • This is done by breaking down the cell wall and cellulose through either;
   • biological approaches such as enzyme breakdown
   • chemical approaches such as exposure to acids
   • physical approaches such as grinding
   • physiochemical approaches such as heating

Question 11

Digestion by Enzymes stage of creating Bioethanol

Answer 11

2. Digestion by Enzymes:
   
   • Broken down biomass is then exposed to amylase which break down the starch and cellulose, converting them into glucose and other sugars
   • This process is aided by hydrolysis

Question 12

Ethanol Fermentation stage of creating Bioethanol

Answer 12

3. Ethanol Fermentation:

- Sugars from step 2 undergo anaerobic fermentation facilitated by yeast producing a large amount of ethanol

Question 13

Purification and Dehydration stage of creating Bioethanol

Answer 13

4. Purification and Dehydration:
   
   • The ethanol produced is distilled via the removal of water
     • It is then converted into the usable form of liquid fuel known as biofuel

Question 14

Applications of Biofuels

Answer 14

• Can help meet our transportation needs as they can be used as an alternative to traditional fuels such as petrol
  
  • Can be stored and used for future generations
  • Can be used in back up power systems and generators
    
    • Can help power schools, hospitals and other community facilities

Question 15

Strengths of Biofuels

Answer 15

Climate Impact:
- Substituting fossil fuels for biofuels can help to reduce carbon emissions and combat climate change

Energy Security:
- As our energy demands increase, we need alternative fuels than fossil fuels as they are non renewable

- Biofuels can reduce our reliance on fossil fuels and provide an ongoing energy source for the long term

Localised Energy:
- Given that biomass can be sourced and farmed around the globe, biofuels can reduce international reliance of imports and exports of fuels

- This decentralises fuel control, increases job opportunities and reduces risk associated with fossil fuel transports

Question 16

Weaknesses of Biofuels

Answer 16

Food VS Fuel:
- On a large scale, using crop lands for harvesting biomass may decrease necessary agriculture output, conflicting with growing food demands

Cost and Difficulty of Uptake:
- Biofuels are typically more costly to produce than traditional fuel and therefore makes it hard for them to penetrate the market since oil prices are low

- They also are not compatible with all our vehicles and energy systems meaning there would be a great cost upgrading these machines to use biofuels

Second Order Environmental Impacts:

• Although producing lower carbon emissions than traditional fossil fuels, they produce second order impacts such as;
  
  • Increased nitrous oxide emissions
  • Deforestation
• Reduction in genetic diversity of some crop species

Question 17

First Generation Biofuels

Answer 17

produced from edible crops which compete directly with agricultural land
- E.g. Corn or sugar cane

Question 18

Second Generation Biofuels

Answer 18

produced from non-edible crops which typically compete less with agricultural land
- E.g. Forestry residues and municipal waste