POSTTREATMENTS OF ANAEROBIC EFFLUENTS

Post-treatments are necessary if anaerobic effluents need to be discha rged into surface waters, because anaerobic digestion alone is not abl e to produce effluents that can meet the discharge standards applied i n most industrialized countries, particularly for suspended solids, pa rticulate GOD, nitrogen, phosphorus and sulphides. This paper has the aim to present some results obtained in the recent years in our labora tory where different comprehensive processes that include anaerobic di gestion have been studied. Discussion will regard: 1) the ANANOX (ANae robic-ANoxic-OXic) process for the treatment of municipal wastewater; 2) a process studied for the biological removal of C, N and P from pig gery wastewater that has a hybrid anaerobic/anoxic reactor as the firs t treatment step; 3) the use of a Sequencing Batch Reactor for the pos t-treatment of digested cheese whey mixed with cheese factory cleaning waters.