The optimal residence time in a methanizer depends on several factors, such as the type of substrate used, the digestion temperature, the type of methanizer and the desired digestate characteristics.

In general, the residence time commonly observed for good digestion of inputs in methane digesters is between 15 and 30 days. However, some substrate types may require longer residence times to achieve complete digestion and maximize biogas production.

In high temperature methanizers (over 50°C), shorter residence times can be used because digestion is faster at higher temperatures. In contrast, low temperature methanizers (between 20°C and 35°C) require longer residence times for the opposite reason: digestion time is shorter at lower temperatures.

It is important to note that residence times that are too long can lead to substrate build-up and problems with the stability of the digestion process. Conversely, residence times that are too short can reduce biogas production and digestate quality.

In the agricultural model and depending on the production of the methanizer, we will see significant differences. The digestate must be carefully observed in order to visually see if the product has been correctly degraded.

In summary, the optimal residence time in a methane digester depends on the specific characteristics of each project and should be determined based on test results and practical experience.