Proceedings

In previous years we have presented HYBACS (hybrid activated sludge) as a method to double the capacity of an existing activated sludge plant, and we have presented various case studies to illustrate the key points. This year we have had the pleasure of working on two very different and unusual upgrades which provide some interesting data.

At Newquay, we installed a HYBACS upgrade to cater for a four-fold increase in population during the Boardmasters festival. Peaks of this magnitude create a particular problem for any biological treatment process due to the rapid changes in load.

In Jubail (Saudi Arabia) we are currently commissioning a HYBACS upgrade at a large industrial effluent treatment plant. The plant serves a huge petrochemical complex so the effluent is highly variable and generally difficult to treat.

These examples highlight the benefits of using the combination of attached and suspended growth which is an inherent part of the HYBACS process.