Verification of an alternative sludge treatment process for pathogen reduction at two wastewater treatment plants in Victoria, Australia
File(s)
Accepted version
Author(s)
Type
Journal Article
Abstract
At South East Water wastewater treatment plants (WwTPs) in Victoria, Australia, biosolids are stockpiled for three years in compliance with the State guidelines to achieve the highest pathogen reduction grade (T1), suitable for unrestricted use in agriculture and landscaping. However, extended stockpiling is costly, may increase odour nuisance and greenhouse gas emissions, and reduces the fertiliser value of the biosolids. A verification programme of sampling and analysis for enteric pathogens was conducted at two WwTPs where sludge is treated by aerobic and anaerobic digestion, air drying (in drying pans or solar drying sheds) and stockpiling, to enumerate and, if present, monitor the decay of a range of enteric pathogens and parasites. The sludge treatment processes at both WwTPs achieved T1 grade biosolids with respect to prescribed pathogenic bacterial numbers (<1 Salmonella spp. 50 g−1 dry solids (DS) and <100 Escherichia coli g−1 DS) and >3 log10 enteric virus reduction after a storage period of one year. No Ascaris eggs were detected in the influent to the WwTPs, confirming previous studies that the presence of helminth infections in Victoria is extremely low and that Ascaris is not applicable as a control criterion for the microbiological quality of biosolids in the region.
Date Issued
2017-08-01
Date Acceptance
2017-04-26
Citation
Journal of Water and Health, 2017, 15 (4), pp.626-637
ISSN
1477-8920
Publisher
IWA Publishing
Start Page
626
End Page
637
Journal / Book Title
Journal of Water and Health
Volume
15
Issue
4
Copyright Statement
© IWA Publishing 2017
Subjects
Science & Technology
Life Sciences & Biomedicine
Physical Sciences
Environmental Sciences
Public, Environmental & Occupational Health
Microbiology
Water Resources
Environmental Sciences & Ecology
Adenovirus
agriculture
E. coli
enteric pathogens
Salmonella
stockpiling
DRYING PROCESS
ASCARIS EGGS
BIOSOLIDS
MICROORGANISMS
SURVIVAL
ASSAY
SOIL
MD Multidisciplinary
Publication Status
Published
Date Publish Online
2017-05-26