Organic waste

Types of waste

Several types of organic waste can be used:

Agri-food industries waste :

Fruit and vegetable by-products, slaughterhouse and canteen waste, very charged organic effluents
Potentially strong in methane

Green waste

Waste of the communities - shearing of grass, sheets etc
Seasonal character

Wastewater treatment plants sludge

Primary and secondary sludge

Grease

Restaurant vats of degreasing
Potentially strong in methane
Greases of flottation

Animal manure :

Liquid manure

Liquid state which facilitates its handling and dilutes other waste
Brings in anaerobe micro-organisms (bacteria)
Stabilizes the pH by facilitating the bacterial reactions and ensures a stability of the medium
Weak methane potential

Manure

High dry matter rate
Support for the bacteria
More difficult to handle and more expensive to use (high demand in energy for the njection in the digester and mixing)
They are used mixed with the liquid manure then sent by pump in the digester or introduced using a hopper

Cultures

Interesting methane potential and can be used at energy ends
However there is no bonus in France for the use of the energy cultures

Residues of cultures (straws, shearing, fans)

High percentages of carbon and easily assimilable in the digesters - goods substrates for anaerobic digestion

By-products

The quantities and the methane potential of the products resulting from the farm only are insufficient in order for the installation to be profitable. It is necessary to find by-products for a co-digestion. These by-products come from:

Agribusiness industries (vegetable scrap or fruit, whey, oil, grease)
Communities (sheerings, sheets, bio waste of the households, sludge of wastewater treatment plants)
Waste of the restorations, large and average supermarket chains

Note: To have the best methane yield it is preferable to use products rich in greases