The degradation of solved organic components processes in four steps:- hydrolysis
- acidogenesis (acidification)
- acetogenesis (formation of acetic acid)
- methanogenesis (formation of methane)
While the hydrolysis, unsolved organic material is broke down into solved fractions.
During the acidogenesis different anaerobic bacteria build organic acids (e.g. butyric acid, acetic acid), different kinds of alcohol, molecularly hydrogen and CO2.
Methane-building bacteria are only able to transform acetic acid, H2 and CO2 into methane. Therefor other compounds have to be converted into one of these components (mainly into acetic acid). All this happens in the step of the acetogenesis.
Finally acetic acid, H2 and CO2 are transformed into methane in the phase of methanogenesis. There are a variety of methanogenetic bacteria. Beside others they differ in their activity at certain temperatures.
