Optimal inlet and outlet configuration made the difference in this new treatment technology
The AAA settler
The AAA settler is a novel A-stage wastewater treatment technology developed by our client Dr. Bernhard Wett (Austria). The process consists of two alternating reactors that switch between feeding, aeration and settling regimes. Stable operation means:
- No wash out of A-stage sludge
- Homogeneous fluidization
At full-scale it is difficult and expensive to test different designs and it is hard to find the optimal configuration. AM-TEAM accelerated this process at the WWTP of Alta Badia, Italy and of Srass, Austria. We tested different pipe configurations and smartly configured the outlet, which had a major impact on system performance. Practical testing of these design changes would have not been possible.
Virtual piloting using a 3D CFD model
Within 2 weeks, different designs of the inlet and outlet structures were tested in 3D and an optimal configuration was found and implemented in practice one week later. The design changes could be tested prior to any investment. The performance of the implemented design is excellent. Emptying the full-scale system and trialing different fixes would have been an order of magnitude more costly and time consuming.
As shown in the below figure, the initial design had uneven flow distribution (dark blue area). The new design had superior performance (designed with CFD) and was implemented at full-scale. The curves on the right indicate the distribution of a 'virtual tracer'. We want a steep curve. The optimal design was more optimal in this regard, while sludge wash out risk was also minimised.
The same applied for the larger full-scale plant at Strass, Austria. Also there, the shift in performance is visible after system optimisation. ('base case' = initial design; scenario 1 and scenario 2 were optimized designs).