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The Jameson Flotation Cell provides a highly
efficient, compact and robust technology for the treatment
of both industrial and municipal effluents. The technology
has been proven in various applications from dairy through
to algae treatment with over 30 applications world wide.
 Professor Graeme Jameson invented the original
Jameson Induced Air Flotation (IAF) Cell at the University
of Newcastle during the 1980’s. The process extended
the conventional and generally accepted process envelope
for removing suspended solids, oils and other material by
generating air bubbles in a ‘bubble column’ without
the need for compressed air or blowers. The process was developed
initially for the mining industry for the recovery of valuable
minerals in mineral processing plants where solids concentrations
can be as high as 250,000 mg/L. Subsequently, the technology
was adapted for waste-water treatment in which the water
becomes the valuable resource to be recovered for recycle
and re-use.
How it Works
The untreated effluent and flocculants are
gently introduced at the top of the unit known as the ‘downcomer’ while
a portion of the clean effluent is recycled back into the
top of the downcomer. For high contaminant concentrations
in the raw water the volume of the recycle stream in a traditional
Dissolved Air (DAF) system would be significant. In this
circumstance, the Jameson Cell is operated in the IAF mode
allowing for high recovery of contaminants with minimal flotation
area and low recycle rates. For low contaminant concentrations
were the recycle fraction is minor, the Jameson Cell can
be configured to utilise the advantages of DAF as well as
IAF.
IAF Mode
Effluent passes through an orifice
to produce a simple liquid jet. The jet of liquid results
in the required high volumes
of air being entrained into the downcomer in much the same
way as air might be entrained into a bucket of water using
a hose. Air is dragged down into the liquid and bubbles
form. The Jameson Cell thereby utilises the energy of the
fluid to induce air into the system, rather than requiring
an external compressor or blower
DAF Mode
Recycled effluent is pumped under
pressure to an air/water contacting vessel to ensure that
the air is dissolved into
the water stream. This pressurised recycle stream released
in to the downcomer operating under a partial vacuum allowing
the air to come out of solution as ‘micro-bubbles’.
In either mode of operation, the bubble/liquid
mixture descends through the downcomer to emerge into a reservoir
(or cell) at the bottom. The cell acts as a disengagement zone
allowing the flocculated material to 'float' to the surface
and form a sludge layer. The sludge overflows the reservoir
into a separate channel whilst the cleaned effluent passes
to the next stage of the process.
 The presence of air bubbles
at the time of flocculation is extremely beneficial as it
results in the bubbles being entrapped
within the actual floc structure at the time of formation.
The incorporation of bubbles in the floc structure provides
buoyancy and allows particles to be floated independent of
their surface characteristics.
Performance
The Jameson Cell Flotation is capable
of:
- 90 - 99% removal of suspended solids
- 90 - 99%
removal of oil and grease
- 90 - 99% removal of insoluble BOD
/ COD
- 90 - 99% removal of algae
- 90 - 99% removal
of precipitated phosphorus
Advantages
- Minimal moving parts and therefore requires a minimum
of maintenance
- Self Aspirating and simple to operate
- No compressor is required
in IAF as the air is self induced
- Low Residence Time resulting
in a small footprint
- Increased efficiency of the Jameson Cell
allows significant reduction in size compared to alternative
technologies
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