Powdered Activated Carbon-Microfiltration for Waste-Water Reuse

Abstract

A range of activated carbon adsorbents have been assessed as pretreatment for microfiltration-based indirect potable reuse (IPR) pilot plant to evaluate the impact on combined membrane fouling and organics removal. Isotherm adsorption analysis showed wide variation between the different adsorbent materials with regards to organics removal and kinetics, and the removal for most of the reagents tested was found to be significantly influenced by temperature. The two commercial adsorbents with the highest removal rates and fastest kinetics were then each evaluated as pretreatment at pilot scale over a six hour period at two doses (5 and 25 mg/l) and operational fluxes (40 and 50 L m⁻² h⁻¹), based on a hollow fibre membrane module. One of the adsorbents provided a reduction in the irreversible fouling rate, and both were found to significantly improve the removal of organics.

Keywords:

• irreversible fouling
• microfiltration
• powdered activated carbon
• reversible fouling
• temperature

ACKNOWLEDGEMENTS

The authors gratefully acknowledge Thames Water R&D who fully funded this work, and especially the Innovation Reuse team.

Notes

All from continuous online monitoring other than *based on periodic spot sampling.