Field performance of two on-site wastewater treatment systems using reactive media layers for nutrient and pathogen removal

Autor(es)

Suhogusoff, Alexandra Vieira ^[1] ; Hirata, Ricardo ^[1] ; Ferrari, Luiz Carlos K. M. ^[1] ; Robertson, William D. ^[2] ; Stimson, Jesse ^[2] ; Forbes, Don ^[2] ; Blowes, David W. ^[2]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Geociencias, CEPAS USP Ctr Pesquisa Aguas Subterraneas, BR-05508080 Sao Paulo, SP - Brazil

^[2] Univ Waterloo, Dept Earth & Environm Sci, Waterloo, ON N2L 3G1 - Canada

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF WATER PROCESS ENGINEERING; v. 32, DEC 2019.
• Citações Web of Science: 1

Resumo

Sparsely populated or peri-urban areas commonly lack access to public water supply and sewerage systems. The inhabitants must make use of excavated wells to meet their water needs and septic systems or pit latrines for domestic wastewater disposal, which can release pathogens and nutrients (nitrate and phosphate) into shallow groundwater. This study compares two on-site sanitation systems improved with permeable reactors for removal of nutrients and pathogens: a lateral flow design at Maryhill site (Canada) and a downflow design at Parelheiros site (Brazil). Both alternative latrines employed two reactive materials: BOF (Basic Oxygen Furnace) slag for pathogen removal and sawdust for nitrate removal. At Maryhill, the sawdust tank was emplaced before the BOF slag tank, and at Parelheiros, the BOF slag layer was emplaced before the sawdust layer. Maryhill latrine was able to oxidize up to 98% of ammonium to nitrate and to remove 99% of nitrate, phosphate, and E. coli from the effluent. Parelheiros latrine was more efficient in promoting nitrification, with almost complete ammonium oxidation, but nitrate removal by denitrification ranged between 13 and 57%, while phosphate and E. coli were completely removed. The BOF slag overlying sawdust layer in Parelheiros design may have negatively affected the performance in denitrifying bacteria due to the high pH created in BOF slag. The Maryhill latrine proved to be a more satisfactory design for nitrate removal. The combined use of sawdust and BOF slag in differing subsurface environments has shown considerable potential for mitigating impacts of on-site sanitation systems on groundwater. (AU)

• Processo FAPESP: 05/00315-5 - MINISIS: um método para avaliação e redução de impactos nos recursos hídricos causados por sistemas de saneamento in situ
• Beneficiário: Ricardo César Aoki Hirata
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 04/03484-0 - Minimização de impactos nos recursos hídricos causados por sistemas de saneamento in situ: estudo piloto em Parelheiros - São Paulo (SP)
• Beneficiário: Alexandra Vieira Suhogusoff
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 06/06562-7 - Implantacao de barreiras permeaveis reativas com capacidade de degradacao de microorganismos em aguas subterraneas.
• Beneficiário: Marcus Sangiorge Ucci
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica