Discfilters Treat Secondary Sewage for Cooling Water

The Client’s Needs

In 2012, Veolia advised the client they would experience issues in their cooling towers if they continued to send the existing quality water to their towers.

A'champion' who worked for the client, listened and had Veolia present its technology to their team. At that time Veolia noted the client was very likely to experience heat rate increases if they did not add tertiary filtration; especially if they used high efficiency fill in the cooling towers.

The power plant personnel wanted to do it, but needed headquarters to approve the funds. Shortly after, the MW rating of the power plant was reduced resulting in large revenue loss and the budget money was approved quickly.

The Solution

Veolia's industrial group reached out to its municipal group to demonstrate to the client the efficiency of its Hydrotech Discfilters for the treatment of reclaim water through a site installation near the power station. 

Following a successful site visit, the client contracted Veolia for the treatment of up to 2,725m³/h (12,000 gpm) of sewage plant effluent for cooling tower make-up. Three of Veolia's largest framed Hydrotech Discfilters will be retrofitted into an existing competitor's media filter concrete basins.

Veolia’s Hydrotech™ Discfilter Process Description and Features

Hydrotech™ Discfilter diagram
Hydrotech™ Discfilter diagram
  • Low cost gravity filtration
  • Low power consumption
  • Small footprint
  • Continuous filtration
  • High water recovery
  • Gravity flow
  • Low backwash rate (no large pumps or sumps required)
  • Automatic backwash and flat panel design easy to keep clean
  • Low installed cost (existing basins for frame design or flat pad for tank designs)

This client chose to install frame units in existing basins. The internals are the same as our tank design pictured above.

Added Value

  • With thousands of Discfilter references, many installed on tertiary filtration in municipal waste treatment, the client was reassured by Veolia’s experience. 
  • The Discfilters will allow an ultimate improvement in cooling tower operation and heat rate, increasing the efficiency of the power unit. This is not only a major financial gain but also a positive step to sustainability. Energy efficiency is often part of a Power generator's sustainability goals - including this corporation.