Pyrogasification is one of the 3 processes that allows the production of biomethane, a non-fossil renewable energy. It consists of heating the waste to more than 100 degrees, in an environment poor in oxygen. Complementary with other renewable energies, pyrogasification contributes to the ecological transition. In this article, we tell you more about this process and its benefits.

Pyrogasification is a thermochemical process which consists of heating waste to very high temperatures (between 400 and 1500 C°), in the presence of a small quantity of oxygen, with the aim of producing biogas. This process uses various biomasses and residual waste: wood residues, dry agricultural by-products, dried sludge, etc. In other words, pyrogasification makes it possible to recover dry residual waste, often intended for incineration or landfill. At the end of the process, all the waste is transformed into gas, with the exception of a solid residue.



The energy generated by this process can be directly stored and injected via existing networks.

Pyrogasification: how does it work?

Pyrogasification takes place in two stages: pyrolysis and gasification.

Pyrolysis

It is a process of thermal decomposition of dry biomass waste, at very high temperatures, between 400 and 1500 degrees, in the presence of a very small quantity of oxygen. Pyrolysis allows you to obtain 3 different stages:

  • A solid phase: solid residues called “coke” or “char”;
  • A liquid phase: an oil or a mixture of hydrocarbons;
  • A combustible gas phase called synthesis gas or syngas.

At the end of the pyrolysis, the quantity of liquid, solid and gas will depend on several elements: the basic composition of the waste, the combustion temperature, the duration of the pyrolysis or even the operating pressure.

Gasification

Gasification is the process of transforming the solid carbon part and the liquid part into synthesis gas. This step consists of heating the dry waste to temperatures between 900 and 1300°C, always in the presence of a small quantity of oxygen. The composition of the syngas will depend on the nature of the incoming resource and the production conditions. At the end of this process, all of the waste is transformed into gas, directly injectable into the gas network, except for a small mineral residue and a minimal quantity of untransformed carbon.

Pyrogasification is therefore the combination of a pyrolysis step followed by a gasification step.

What are the advantages of pyzogasification?

  • It makes it possible to recover dry residual waste and non-recyclable resources: it is a response to the problems of processing certain waste in the territories and an alternative to costly actions such as incineration and landfilling of waste.
  • It is a clean, local, storable and directly injectable renewable energy: synthesis gas can be injected directly into gas networks and can be used for domestic, industrial or mobility uses. As this energy is easily stored, its use adapts to different needs throughout the year.
  • The gas produced by pyzogasification has a favorable environmental impact: reduction of pollutants and near carbon neutrality.
  • It makes it possible to set up a local circular economy: the whole challenge is to carry out local processing of locally produced waste. Thanks to gasification, non-relocatable jobs are created.

What are the prospects for pyzogasification?

Pyrogasification, which corresponds to the production of 2nd generation biomethane, is a process that is still booming. Its industrial development should take a few more years, but it participates in the energy transition led by the gas sector. Many waste treatment players, local authorities and even industrialists have committed to initiating projects around pyrogasification.

By 2030, the plan is for pyrogasification to represent 6 TWh of gas injected per year in France. This would make it possible to recycle 3 million tonnes of waste per year and reduce CO2 emissions by 1 million tonnes per year