biogas

BIOGASEnergy & Environment

What is Energy? What are different types of energy?

Light & Heat Kinetic & Electrical

Potential

Noise Chemical

Can you create energy?

No.

Energy is conserved.

Energy can be transformed but not

created.

Examples of Energy Transfer

1. Clap Your Hands

Kinetic Noise

Examples of Energy Transfer

2. Rub Your Hands

Kinetic Heat

Examples of Energy Transfer

3. Switch on a light bulb

ElectricalHeat Light

Examples of Energy Transfer

4. Light a match

ChemicalHeat Light

A match is an example of using a fuel

What is fuel?

Examples ?

Wood Oil

Stored Chemical Energy

Chemical

Electrical

Kinetic Heat

Light

Disadvantages of Fuel

Expensive Polluting

Diminishing Resources

Time to gather

What if we had a fuel that was none of these?

Biogas Uses waste material to transfer chemical

energy to other forms of useful energy!

Electrical

Kinetic Heat

Light

Chemical

Different Types of Gas Plant:Gobar Gas Plant

Stops air getting into the digester- creates anaerobic condition

Gas to kitchen

Sludge used as a fertiliser

Real Gobar Gas PlantsVigyan Ashram

Real Gobar Gas PlantsVigyan Ashram

Mixer

Digester Tank

Gas Holder

Sludge

Gas to kitchen

Real Gobar Gas PlantsVigyan Ashram

Gas to kitchen

Latrine

MixerGas collector

Digester

Different Types of Gas Plant:Sausage Bag Gas Plant

Sludge used as a fertiliser

Gas to kitchen

•Quick to construct•May require importing•May require protection from sharp objects and vermin

How Does Biogas Work?Anaerobic Digestion No Oxygen

More Microorganisms

Microorganisms found naturally in cow’s stomach

No Oxygen

Nitrogen and Carbon

Slurry

For Cooking

What is important?Ratio of Nitrogen to Carbon

Too much nitrogen

Too much N means no

growth

1x Nitrogen : 30x Carbon neededIt can be fixed by dilution

What is important?Ratio of water and Nutrients Ratio

1 water :1 solid waste Nutrients

carbon (C) and nitrogen (N)○ N= provide nutrients for the growth and

multiplication of the anaerobic organisms

+ N =

What is important?

StirringPrevents scum growth

Retention TimeEffected by temperature, dilution, loading

rate, etc.A normal period for the digestion of dung

would be 2 to 4 weeksAt high temperature bio-digestion occurs faster

○ Between 20 and 30

Advantages 1x =3kW hours of electricity Save on fossil fuel. Save time collecting fuel. Improve hygienic conditions. Reduce pollution.

Save Money Protect ForestsProduce high quality fertiliser

Summary Questions1. Can you create energy?

2. When you rub your hands what happens(energy transfer)?

3. Name one disadvantage with fuel

4. What two nutrients are important in a biogas plant?

5. Briefly explain what is happening in this picture.