Optimal bulking agent particle size and usage for heat retention and disinfection in domestic wastewater sludge composting

Composting of two types of sludge produced in wastewater treatment plants, raw sludge (RS) and anaerobically digested sludge (ADS), has been systematically studied by means of the experimental design technique. The results have been analyzed using a full factorial experimental design in order to det...

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Detalhes bibliográficos
Autores: Gea Leiva, Teresa|||0000-0003-2523-4797, Barrena, Raquel|||0000-0002-6077-7765, Artola, Adriana|||0000-0002-0524-2119, Sánchez, Antoni|||0000-0003-4254-8528
Formato: artículo
Fecha de publicación:2007
País:España
Recursos:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:163589
Acesso em linha:https://ddd.uab.cat/record/163589
https://dx.doi.org/urn:doi:10.1016/j.wasman.2006.07.005
Access Level:acceso abierto
Palavra-chave:Anaerobically digested sludge
Composting
Disinfection
Experimental design
Optimization
Raw Sludge
Salmonella
Simulation
Descrição
Resumo:Composting of two types of sludge produced in wastewater treatment plants, raw sludge (RS) and anaerobically digested sludge (ADS), has been systematically studied by means of the experimental design technique. The results have been analyzed using a full factorial experimental design in order to determine the optimal conditions for composting such sludges in terms of bulking agent particle size and bulking agent:sludge volumetric ratio, two of the key parameters to ensure an optimal performance of the composting process. The objective function selected was a simulated death kinetics of Salmonella, which was chosen as a model pathogen microorganism to represent the disinfection of the material. For both types of sludge, optimal values were found at 5 mm bulking agent particle size and 1:1 bulking agent:sludge volumetric ratio when a Gaussian function was fitted to the experimental data. Pilot scale experiments using optimal values obtained were successfully undertaken and confirmed a full disinfection of the sludge by means of the composting process. A mathematical model to simulate the disinfection performance of a composting material is presented. The model can be applied to simulate the disinfection performance of a given pathogen.