ANAEROBIC DIGESTION OF MUNICIPAL SOLID WASTE, BIOWASTE COMMERCIAL WASTES - EXAMPLES OF: 1) SUCCESSFUL REVAMPING OF EXISTING PLANTS 2) CO-DIGESTION OF BIOWASTE AND COMMERCIAL WASTE WITH AGRICULTURAL RESIDUES

摘要

Anaerobic digestion (A.D.) of the organic fraction of municipal solid waste (MSW), Biowaste andCommercial waste combines the reduction of waste to be landfilled with the production of fertilizer and renewableenergy, generating electrical and thermal energy by the valorization of the generated biogas. Thus, an A.D. plant canprovide environmental, economical and social benefits. In case of co-digestion with other biomasses (such as manureand agricultural substrates) further economical and process benefits can be achieved. Unfortunately waste containsimpurities that, if not efficiently removed, cause to the plant heavy biological and mechanical-hydraulic problems.Ecoparc 1 plant in Barcelona was started in 2001 and was planned to treat 300.000 t/a (250.000 t/y of MSW and50.000 t/y of organic fraction from MSW). Mainly because of insufficient elimination of contaminant upstream, theplant never reached the expected treatment capacity, suffering high solid sedimentation in digester, pump clogging,low biogas production and high fraction to be landfilled. Biotec successfully revamped the plant by applying BTA?Hydromechanical pre treatment. Similar results have been achieved with the revamping of Cà del Bue in Verona Italyand Burgos in Spain. Castelleone -IT- co-digestion plant started in 2010 and is authorized to treat 100.000 t/y (20.000t/y of biowaste, 6.000 t/y of commercial residues, 6.000 t/y of agricultural substrates and 68.000 t/y of manure),generating 1.676 kWel and producing approx. 100.000 t/y of digestate, successfully used as fertilizer after propersanitation. In this paper the above mentioned plants are presented.