An Intelligent Water Networks (IWN) funded collaboration between Central Highlands Water (CHW) and Victorian University (VU) has been nominated for the AWA Research Innovation Award.
In May 2018 the 10-week pilot investigation was initiated to research the removal and recovery of both the nutrients nitrogen (N) and phosphorus (P) at the Ballarat South Waste Water Treatment Plant.
The pilot featured two technologies:
Vacuum membrane distillation (VMD) unit, custom designed for the purpose of ammonia removal and
A struvite crystalliser to precipitate phosphorous and some of the ammonia.
The trial showed that the struvite crystalliser demonstrated > 90% P removal along with >30% N removal. The results were encouraging and this promising technology appears ready for a scaled trial.
The vacuum membrane distillation process achieved a > 90% nitrogen reduction, this process is technically feasible and could be an alternative to current N removal practice.
When the two technologies were used in series, it was seen that the residual nitrogen and phosphorous components were between 3 to 8%. The intellectual property agreement between all relevant parties enables the technology to be adopted by other Victorian water corporations.
With phosphorous being a dwindling resource in the world, this study also focused on the recovery of phosphorus (along with some of the nitrogen) in a form that could be used as an organic fertilizer in the agricultural industry. The principle of this technique is based on creating a favourable condition to produce useful form of phosphate precipitate eliminating the formation of unwanted phosphate products.
This technique could also be introduced to trade-waste generators that produce large volumes of effluent with high nutrient concentrations that could potentially impact central wastewater treatment facilities.
Unfortunately this study didn’t win this year, but the fact that IWN projects are gaining national recognition is proof of the value for money IWN can offer.