Pilot-scale aerobic granular sludge in the treatment of municipal wastewater: Optimizations in the start-up, methodology of sludge discharge, and evaluation of resource recovery

• Autor(a) principal: Rollemberg, Silvio Luiz de Sousa
• Data de Publicação: 2020
• Outros Autores: Oliveira, Lorayne Queiroz de, Barros, Amanda Nascimento de, Firmino, Paulo Igor Milen, Santos, André Bezerra dos
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/71244
• topic: Aerobic granular sludge; Wastewater treatment; SNDPR; Resource recovery; AGS reactor optimization

This work evaluated the formation, maintenance, performance, and microbiology of a pilot-scale aerobic granular sludge reactor treating low-strength municipal wastewater under tropical climate conditions. Additionally, different resource recovery possibilities (phosphorous, tryptophan, and alginate-like exopolysaccharides) were investigated from the produced sludge. Granulation occurred after 35 days without external carbon source supplementation (CODinf ≈ 461 mg/L; COD/DBO5 ≈ 3.2). Some protocols were implemented: (i) fat separation to decrease granule flotation; (ii) high exchange rates (60%) during rainy periods to increase the organic load; (iii) selective sludge discharge methodology. After granules formation, optimizations were done to improve reactor performance (COD, BOD, NH4+, and PO43− removals close to 90%), and energy demand reduced from 0.43 (start-up) to 0.25 kWh/m3 (after optimizations). The produced sludge had a high concentration of phosphorus (0.020 g P/g VSS), tryptophan (0.048 g tryptophan/g VSS), and alginate-like exopolysaccharides (0.219 g ALE/g VSS), indicating a good resource recovery possibility.