PROCESS FOR THE BIOLOGIC TREATMENT OF ORGANIC WASTES AND PLANT THEREFOR

摘要

Process for the biological treatment of organic wastes, of the type comprising a first anaerobic digestion phase and a second aerobic digestion phase in succession, a filtration phase of the solid substance being provided after the two digestion phases, furthermore comprising a separation phase of the biogas released in said anaerobic digestion phase and a nitrogen recovery- phase from the exhaust gases rich in ammoniac substances separated from said aerobic digestion phase. The solid substance coming from each of said filtration phases is separately returned to the respective digestion phase, while the liquid phase coining from the filtration phase downstream of the anaerobic digestion phase is sent to aerobic phase. In the nitrogen recovery phase the gaseous current consisting of said exhaust gases rich in ammoniac substances is treated with a solution of carbonic acid supplied in countercurrent in a first gas/liquid contacter to obtain a mixture of nitrogen salts (ammonium bicarbonate, ammonium carbonate, etc.).