2013 11-25 d effective solutions -prostream

AQUASYSTEMS INTERNATIONAL N.V.

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WELCOME

Effective Solutions For Aeration, Mixing And Decantation In WWT

Plants


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ABOUT US

Headquarters in Halle near Brussels:> 25 employees in Halle, including productionOwn engineering, research and development departmentOwn test facility (2 test basins)

Subsidiary in Springdale / Arkansas:> ca. 15 employees in SpringdaleOwn test facility (2 test basins)


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ABOUT US

Products :1) Aeration2) Mixing3) Decanting4) Floatables

handling5) Cover for

surface aeratorsAlso available as

RENTAL EQUIPMENT


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SBR and CAS with Deni/nitri are state of the art, high concenctrations at start, low at the end means:

High (peak) oxygen demand at the start, low at the end (effluent concentration)

High sludge load and low sludge age = lower alpha-factor as used for calculation

Low turbulence = low alpha-factor

Activated sludge plants and aeration


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Conclusions for the design of an optimal aeration system in WWTP

Adjustable to high oxygen demands at the start and low demands at the end

Take into account the effect of the sludge load on the alpha-value

High turbulence for high alpha-value Non-clogging and non-aging Consider the SRT and changing water levels Combined with mixing


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Aeration

AQUA TURBO® AER-GS and MIX-GS

Air


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AQUA TURBO® AER-GS


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Aeration

=> Alpha factor α is mostly ≥ 0,9 for normal waste water and viscosities and densities ≤ 0,8 % due to :- sheared microbubbles are dispersed away from each

other radially to minimize coalescence - intensive mixing at averagely ± 2 W/m³ , equal

homogenization and turbulence raises the α factor considerably

- radial dispersion with induced flow raises the bubble retention time



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Aeration

Lower pressure and blower power consumed for the same airvolume, due to low headloss

System cannot get damaged by sudden blower pressure differences (errors, waterlevels lower than anticipated, ...)

No clogging possible due to the open impeller mixer and central air supply

1 system aeration/mixing-nitrification/denitrification. Mixing is excellent when blower is shut off



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Aeration

VFD for mixer : Optimization of the process and for economical operation

VFD for blower : Finetuning of oxygen supply : Same homogenization capacity AND same oxygen transfer efficiency when blower shuts off or operates at lower frequency, which can be energy saving over other aeration systems that need air feed to have a decent mixing capacity



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Aeration

Low wear and tear due to slow speed 20 to 40 RPM, no vibrations, no erosion, no clogging, no network of pipelines and water does not have to pass through pumps.

Stainless steel design : Impeller 2,3 m diameter is the maximum as basis, and we use extensions to 2,8 m depending on airflow : Easy transport, robust, less susceptible for transport damages and eventual damages in the reactors.



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Major concerns about mixing

Floating or fixed installation Downward directed flow against floatables Vertical movement reduces death times, sludge gets into

suspension fast after sedimentation and decantation No oxygen intake during operation (denitrification) No clogging Maintenance free


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Vertical mixing


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Mixing

Lower consumption due to spiral flow guiding along the cone.

The spiral curvature of the mixing flaps of EVERY mixing cone gets adapted on basin dimensions, solids concentration, ...

AQUA TURBO® MIX-GS


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Vertical downdraft mixing

Flow pattern for vertical downdraft mixing:


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MixingAQUA TURBO® down draft mixer MIX-BS

1) ENCAPSULATED motor : does not get damaged by foam

2) Center of gravity below water level3) Impeller design is gentle to the activated sludge4) Screw centrifugal impeller : Robust, no clogging, low vibrations5) None or very low oxygen supply

during mixing : Calm water surface 6) For big rectangular basins, one can use

only one MIX-BS instead of having to use two submersible mixers7) No guiding tubes needed, very flexible8) Basin does not to be emptied for

installation 9) Bearings no maintenance for 4 to 5 years


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Floatables and mixing

Grease and other floatable materials are returned and mixed into the liquid phase within the basin, where this can be removed biologically Based on Mix-AS SCREWPELLER® + Extra SCREWPELLER® flight that pumps upward. = Dual action flightsüThis extra SCREWPELLER® flight avoids vortexing and cavitation and disturbes the layer of floatables to ensure its entrainementHigh reliability and simple installation

Double action:→ Mixes the whole basin→ Prevents grease and floatables to accumulate later in the clarifier, or in the SBR-reactor

AQUA TURBO® FRED Floatables reEntrainment Device


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Floatables and mixingAQUA TURBO® FRED Floatables reEntrainment Device


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Decantation device = essential unit for SBR

Floating installation Only open during decantation Effluent below the water surface Horizontal inflow Limiting the flow rate Avoid unattended evacution Only robust and approved devices


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Decantation device


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Decantation deviceAQUA DECANTTM - AD-MCA (mechanically closed) :

Decanter is kept close during aeration and mixing phase by means of anactuator that holds the cone against the float : No sludge can enter in thecone during aeration and mixing periods


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Decantation device

ADMCA with hinged discharge pipe

ADMCA with telescopic discharge pipe

ADMCA with flexible hose

AQUA DECANTTM - AD-MCA (mechanically closed) :


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Other aeration and mixing devices from Aquasystems

Technology

2013 11-25 d effective solutions -prostream