The challengeThe operator of the wastewater treatment plant, Ex Central Highlands Water, aimed at improving the sludge mixing in the digester and at minimizing foaming in the tank. There was an initial preference to use jet mixers because this would have been straightforward with standardized spare parts and maintenance. The challenge was to convince the operator that Sulzer’s radically different thinking could dramatically reduce energy consumption and improve process outcomes at the same time.
Sulzer offered a Scaba agitator option, which was very competitive and economical. The capital investment was smaller, the mixing efficiency higher and the installed power much lower compared to jet mixing. In addition to the energy saving, the maintenance requirements, noise levels and footprint of the Scaba agitators were superior to the jet mixing system.
Scaba top-mounted vertical agitators are used for mixing and agitating process liquids in many industries, including wastewater and industrial applications. They ensure homogenous mixing results, high process reliability, high efficiency, low operating costs and low environmental stress.
The Scaba agitators were factory tested and field tested. They have given excellent mixing results, which in turn has improved the sludge digestion. The gas production increased by 100% versus compressed gas mixing.
Sulzer’s highly efficient Scaba agitators are an optimum fit for sludge digestion. VFA (volatile fatty acids) decreased from 90% down to 65-70%. After the installation of the Scaba agitator, gas production has increased by 100%. Achieving this mixing energy with a 1.5 kW motor is remarkable., Process Engineer, Ex Central Highlands Water
- Increased gas production versus old system with compressed gas mixing
- Reduced footprint, noise and maintenance costs
- Sulzer’s catalogue-claimed performance was achieved in site testing
- Easy installation of the Scaba system
- Less vibration
Sulzer Scaba 60FVPT-Lbb
|Motor||ABB 1.5 kW 1’500 rpm|
|Gearbox||NORD 16 rpm|
|Tank diameter||10.67 m|
|Tank height||8.0 m|
|Fluid Incoming solids||5% DS|
|Purpose||Prevent sedimentation of organics|