Your web browser is out of date.

Update your browser for better security, speed and to get the best experience on this website.

Update your browser

Full-scale polishing systems

Posted on
Shutterstock 33595688

Prior to the development of MBR technology, clarification and substantial disinfection of wastewater was achieved by employing microfiltration (MF) or, most often, ultrafiltration (UF) downstream of a classical activated sludge (CAS) process. This ‘non-integrated’ combination of membrane technology with biological treatment is widely used in water reuse applications, and is often preferred over MBR technology since the membrane component can simply be placed downstream of the secondary clarifier with no further modification of the existing infrastructure.

Non-integrated vs integrated membrane technology Credit: Judd Water & Wastewater Consultants
Non-integrated vs integrated membrane technology
Non-integrated vs integrated membrane technologyCredit: Judd Water & Wastewater Consultants

There are three types of water reuse applications, where wastewater is recovered and reused for some purpose:

  • Non-potable reuse (NPR), where the recovered water is used for some purpose other than potable supply (e.g. irrigation, industrial process water, etc)
  • Indirect potable reuse (IPR), where the recovered water passes through an ‘environmental buffer’ before being used as a supply of potable water, and
  • Direct potable reuse (DPR), where the recovered water is used as a potable water supply without passing through an environmental buffer.

IPR and DPR systems employ municipal wastewater as the feed, and are subject to very high treated water quality standards. NPR can either be based on industrial effluents, where the product water is most often reused on site, or municipal wastewater.

About this page

'Full-scale polishing systems' was written by Simon Judd

This page was last updated on 06 May 2022


Information on this page may have been supplied by third parties. You are reminded to contact any third parties to confirm information is accurate, up to date and complete before acting upon it. accepts no liability for information provided by third parties, actions taken on the basis of this information or information held on third-party websites.

© Text copyright Judd & Judd Ltd unless otherwise indicated on this page