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La Méthanisation
Why go into biogas?
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Biogas industry = economic interests + agronomic interests + environmental interests!

Recycle waste, produce renewable energy, improve air and soil quality, produce a natural fertilizer, promote the maintenance of French agriculture, offer an ecological alternative to traditional fuels (Bio NGV)

Operation of a biogas unit

Biogas production is a natural process of recycling fermentable organic matter, in an oxygen-free environment, due to the action of numerous micro-organisms that transform the organic matter into biogas and digestate. This transformation can be broken down into 4 main stages: hydrolysis, acidogenesis, acetogenesis and methanogenesis. It takes place naturally in certain environments, such as marshes, but can be implemented voluntarily by man in dedicated units called "digesters" and under controlled conditions (temperature, tightness, absence of oxygen, low pressure, etc.).

Methanization allows the production of a gas, called biogas, composed of methane (CH4) at 60% and carbon dioxide (CO2) at 40%, which can be used as energy in the form of electricity and heat thanks to a cogeneration engine, as biofuel or which can be injected into the natural gas network after a purification stage, becoming biomethane.

The agricultural biogas is not a new process!

It is a natural process of degradation of organic matter in an oxygen-free environment that produces a gas, called biogas. This degradation is done by bacterial way in particular conditions (PH, temperature, ratio carbon/nitrogen, etc.) Indeed, a complex population of bacteria will transform the organic matter introduced in the tank whose duration of stay is approximately 60 days, to produce this biogas. This reaction generally takes place at 40°C, a temperature ensured by continuous heating of the tank called digester. The biogas is composed of about 50% to 65% of methane (CH4), 20% to 50% of carbon dioxide (CO2) and some trace gases (NH3, N2, H2S). The biogas recovery allows to obtain energy in electricity, heat or biofuel as well as digestate (natural fertilizers) which can be recovered within the framework of a spreading plan.

Advantages of biogas as a renewable energy source

Economic interests of Biogas

Biogas production, a strong economic stake: 

  • Additional income for the project owner through the sale of electricity or biomethane. The 15-year purchase obligation contract offers long-term visibility, which is uncommon in agriculture,
  • Contribution of a digestate of high fertilizing value which will allow to do without chemical fertilizers in part or in totality,
  • Valorization of agricultural, household, community or food industry waste: you will treat exogenous co-products and will be paid for degrading them.

Agronomic interests

Biogas production generates many agronomic interests: 

  • A digestate obtained by the process of biogas is of load in pathogens reduced compared to the initial effluents. A hygienization at the entrance or exit of the digester allows an increased abatement of pathogens.
  • A digestate in liquid form contains a high proportion of ammoniacal nitrogen. In solid form, dry or in humus, it can be easily exported to the most distant lands and above all rapidly assimilated.
  • Reduction of weed seeds by treating the straw of the crops, thus reducing their germination power.
  • A partnership between farmers and cereal producers is established through the exchange of organic matter to be methanized and spread.

Environmental interests, take the role of the ecological transition!

The process of biogas allows the production of a renewable and profitable energy, while improving the environmental performance of your farms. It comes in different forms: 

  • Fuel for vehicles,
  • Purified biogas that can be injected into the natural gas network,
  • Electricity
  • Heat that can supply your farm and neighboring networks.

Biomethane replaces fossil fuels such as oil and coal.

The process of biogas production also enhances other environmental aspects: 

  • Reduction of greenhouse gases (CH4, CO2...)
  • Reduction of ammonia gas losses during storage,
  • Important reduction of odors during the storage of effluents and during the spreading
  • Reduction of water pollution (in connection with the optimal use of digestate)