Recent Brazilian regulations do not allow biosolids rich in human pathogens to be used in agriculture. Thus, this work aimed to evaluate the feasibility of producing pathogen-free biosolids by composting and vermicomposting sewage sludge from city of Brasilia. Sawdust and woodchips or yard trimmings were mixed with tertiary sewage sludge as carbon source and bulk agent to build piles bigger than 5 m³. Mature compost was then inoculated with worms to be vermicomposted. Worms developed well and improved the physical and sanitary characteristics of the composted sludge. The sewage sludge originally presented 4.7 viable eggs g-1 of dry solids and the composting process could reduce it to values from non-detectable to 0.34 viable eggs g-1 of dry solids. Such figures represent sanitation efficiencies from 93 to 100%. Non-viable eggs were detected after vermicomposting. Therefore, such a process showed itself capable of producing helminthe-free biosolids, which are allowed for agricultural use in Brazil.
helminthes; pathogens; stabilization; hygienization
