Decomposition - AQAAnaerobic decay, methane gas and biogas generators
Decomposition, or decay, is the breakdown of dead matter. The rate at which this happens depends upon the number of decomposing microorganisms, the temperature, and water and oxygen availability.
Anaerobic decay, methane gas and biogas generators
anaerobicWithout oxygen.decayWhen plants wither and die. occurs when bacteria and fungi break down dead matter without oxygen. This can happen naturally in some soils, particularly water logged soils, and in lakes and marshes. When people overwater their houseplants and flood the roots, anaerobic decay can occur, which can kill them.
The products of anaerobic decay are methane and carbon dioxide. We use methane as a fuel. Both gases are greenhouse gasThe gases responsible for global warming - carbon dioxide, methane, nitrous oxide and CFCs (chlorofluorocarbons)., which contribute towards global warmingThe rise in the average temperature of the Earth's surface. .
Biogas
We can use the process of anaerobic decay or decomposition to provide us with fuel. Together the methane and carbon dioxide produced are called biogasA type of biofuel (methane) derived from the action of bacteria on animal manure or other organic waste.. This is a source of renewable energyPower that is generated using natural resources that will not run out, eg wind and wave power.. Biogas generators are large vessels in which animal waste or specially grown crops such as maize are allowed to anaerobically digest. If domestic waste is used as a source of methane, this also reduces the volume of domestic waste added to landfill sitesPlaces where refuse is buried underground..