The size of a methanizer

Methanizers all have a common mission, which is to transform biowaste into green energy (whether it be electricity, heat, green gas, etc.). The process of this transformation is also similar: the recovery of biogas produced by the natural degradation of these elements.

But beyond this common core, we find methanization sites which are built on different scales.

Site size can vary greatly depending on several factors, for example:

• The quantity and quality of raw materials available
• The energy requirements of the installation
• The location of the installation and the possibilities it offers
• Budgetary constraints
• Local regulations

The size of a methane digester can be defined based on the input volumes or tonnages, i.e. the amount of material that is planned to be incorporated per day or per year. This quantity must first be estimated and then declared to the competent authorities who may or may not authorize the operation of the site.

The greater the volume of inputs planned, the more carefully the application files will have to be prepared to properly study all the potential risks and the means put in place to prevent them (see our dedicated article on ICPE ).

There are 3 main regimes depending on the nature of the materials processed and the quantity incorporated and each of these regimes provides for a certain number of systems to be put in place:

• Volume less than 30 tonnes per day: Declaration regime
• Volume between 30 and 100 tonnes per day: Registration regime
• Volume greater than 100 tonnes per day: Authorization regime

The smallest methane digesters are generally for farms or small communities, and are adapted to meet local energy needs: lighting or local heating for example. These are generally cogeneration or boiler models.

Medium-sized biogas plants can process tens of thousands of tons of biowaste per year. They can be operated by large farms, by players in the agri-food industry or by municipal waste treatment centers. They can produce the electricity needed for their own operation and more, or inject green gas into the networks. This is often the case for agricultural biogas plants, for example.

Finally, the largest methanizers are designed to process hundreds of thousands, or even millions of tons of organic waste per year. This may be the case for large urban centers that process municipal waste on a large scale, or for large-scale industrial methanizers. These are often integrated into complex waste management infrastructures.

Methappro has referenced all active methanizers in France, of all sizes, to create the most relevant and local links possible with biowaste producers. Biowaste producers, contact us atlouis@methappro.fr