Sludge management systems for urban wastewater treatment plants – A tool for the decision makers
E.C.N.F. Duarte1, M.B.O. Martins2, C.P. Trindade3 and I. Ribeiro4
Full Professor, Instituto Superior de Agronomia, Departamento de Química Agrícola e Ambiental, Tapada da Ajuda 1349-017 Lisboa, Portugal, tel/fax: + 351 21 365 34 25, Email: eduarte@isa.utl.pt Engineer, Instituto Superior de Agronomia, Departamento de Química Agrícola e Ambiental, Tapada da Ajuda 1349-017 Lisboa, Portugal, tel/fax: + 351 21 365 34 25, Email: mmartins@isa.utl.pt Project manager, AGROGES, Sociedade de Estudos e Projectos, Lda, Av. da República, 412, 2750-475 Cascais, Portugal, tel: + 351 21 484 74 40, fax: + 351 21 484 74 41, Email: cptrindade@agroges.pt Engineer, AGROGES, Sociedade de Estudos e Projectos, Lda, Av. da República, 412, 2750-475 Cascais, Portugal, tel: + 351 21 484 74 40, fax: + 351 21 484 74 41, Email: iribeiro@agroges.pt
ABSTRACT
The main goal of the work developed is to present the results from a set of studies conducted in different regions of Portugal where a conceptual model of sludge management was applied. In order to achieve the objective of the use of organic resources on land, all the partnerships (producers, users, authorities, regulators) should be convince that the sludge/biosolid is safe, sustainable, trusted and welcome. The selection of the use/disposal method or management system was based on technical factors such as, local geography, climate, land use, availability or disposal sites and regulatory constrains, giving also emphasis to the local traditions, personnel experience and public opinion. The wide spread of different WWTP by region in study (size, treatment process and local specific parameters) led us to the construction of hypothetical sludge management scenarios. The decision depends on several factors, namely, economical, environmental, logistical, energy recovery and land use. This tool can be used, not only for the region in study, but also for different municipalities, although it should be adapted to the different “municipality specific” and “site specific” parameters. The results were thoroughly analysed to identify parameters that could have a potential influence on the results.
