TECHNOLOGY FOCUS - BIOLOGY - Preferred Bacteria: The facultative, anaerobic fermentation is performed by facultative anaerobic bacteria. The bacteria are facultative, anaerobic mesophilic bacteria.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Method: The mineralization by chemical and/or biological method involves performing mineralization by biological method and optionally also by chemical method. The mineralization by biological method involves subjecting the organic material to facultative, anaerobic fermentation, where organic nitrogen present in the organic material is converted into inorganic nitrogen during the anaerobic fermentation, and the facultative, anaerobic fermentation essentially does not produce any biogas. The facultative, anaerobic fermentation is conducted at 15-42 degrees C, preferably 37 degrees C. The facultative, anaerobic fermentation is performed at pH of 6-8, preferably 7.5-8. The facultative, anaerobic fermentation converts essentially all of uric acid of the organic material into ammonium or ammonia comprising compounds. Less than 10% volatile solids, preferably less than 1% volatile solids are lost from the organic material during the facultative, anaerobic fermentation. The facultative, anaerobic fermentation is performed for less than 24 hours. The facultative, anaerobic fermentation is carried out both in the absence as well as in the presence of atmospheric oxygen. The fermentation conditions are strictly anaerobic. The fermentation conditions are chosen from aerobic fermentation conditions, anaerobic fermentation conditions, and their combinations. Preferred Components: The carbon dioxide containing gas is biogas. The carbon dioxide containing gas diverted to the organic material in the buffer tank is biogas diverted to the buffer tank from anaerobic fermenter, where anaerobic digester is connected to the buffer tank and receives input biomass material in the form of organic material present in the buffer tank. The diversion to the buffer tank of carbon dioxide containing gas, such as biogas, controls the pH of the organic material present in the buffer tank. The pre-incubated and lime pressure cooked organic material present in the buffer tank is diverted to anaerobic biogas fermenter.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The plant further comprises separation unit for separating organic materials diverted to the separation unit from one or more fermenters, where the separation of the organic materials results in the generation of solid organic material fraction and liquid fraction comprising one or more sources of nitrogen, and unit diverting the liquid fraction comprising one or more sources of nitrogen to the lime pressure cooker, where the liquid fraction is mixed in the lime pressure cooker with first organic material comprising one or more sources of nitrogen. EXAMPLE - No suitable example given.