The application of fine-mesh sieves (<0.35 mm) as pretreatment for municipal biological wastewater treatment gives an opportunity to recover resources and increase the sustainability of wastewater treatment processes.
Sieves are traditionally used for single-stage mechanical treatment (typical mesh of 0.35 mm), or in combination with a membrane bioreactor (MBR, typical mesh >0.7 mm).
When sieves with a mesh of 0.35 mm are used on raw sewage, these Dutch researchers observed that cellulose fibres (mainly originating from toilet paper) are removed efficiently from the influent with high recovery and purity.
The application of sieves as pretreatment for conventional activated sludge processes has been evaluated based on pilot plant research at three wastewater treatment plants (WWTPs) in the Netherlands.
With sieving applied only to the dry weather flow, the overall energy usage of the WWTP including sludge treatment can be reduced by at least 40%, with a payback time of seven years.
Water Research, Volume 47, Issue 1, 1 January 2013, Pages 43–48.
