Water treatment for the aquaculture industry

Krüger Kaldnes
Hegnasletta 11
N-3217 Sandefjord, Norway
Tel: +47 91 60 80 00
Fax: +47 33 48 50 01
www.veoliawaterst.com
For more than 20 years, Krüger Kaldnes has supplied the aquaculture
industry with solutions and technologies for high quality water
treatment. Our Kaldnes Moving Bed process is used in a large number
of fish farms all over the world and is today the leading technology for
biological water treatment within the industry.
Krüger Kaldnes is part of Veolia Water Solutions & Technologies
comprising world class technical know-how and technologies for water
purification. As such Krüger Kaldnes offers a wide range of solutions that
can be tailored to meet the highest standards providing prime quality,
energy efficiency and operational friendly water treatment systems.
VWS Photo Library - © Richard Hermann/Galatée Films / AnoxKaldnes - 04/10
Water treatment
for the
aquaculture industry

Water treatment systems
for the land-based
aquaculture industry
A full range of solutions:
> Recirculating Aquaculture Systems (RAS)
– up to 99.99% reuse
> Treatment of intake water
> Conditioning of water during production
in flow through systems
> Treatment of effluent water from fish farms
> Sludge treatment
> Treatment of water and waste from fish abattoir
and processing
Intake water treatment
Krüger Kaldnes offer systems for preparation of intake water where
the treatment may typically include one or more of the following unit
processes:
> Solids removal (Filtration)
> Disinfection
> Alkalinity and pH adjustment
> Biological treatment
> CO 2
and N 2
stripping
> Oxygenation
Krüger Kaldnes RAS
For land-based fish farms, Recirculation Aquaculture Systems (RAS) provide
significant advantages towards flow through systems. Excellent water quality,
rich water quantities and preservation of temperature are all key factors to provide
good health and optimal growth conditions for fish.
Krüger Kaldnes RAS plants are tailored for optimum conditions related to fish species, degree of recirculation, fish
tank configuration and source of raw water. Components that typically will be removed in a Krüger Kaldnes RAS
plant include organic matter, total ammonium nitrogen (TAN), suspended solids, CO 2
, N 2
and harmful bacteria/
virus. They will also provide optimum conditions related to pH and alkalinity. Krüger Kaldnes’ solutions are being
used for both fresh- and saltwater systems.
AnoxKaldnes MBBR
State-of-the-Art Solutions and Technologies
Hydrotech drum filters
Water conditioning in flow through systems
Elevated CO 2
concentrations and marginal O 2
levels are the main challenge in flow through systems. This has a
negative impact on fish welfare and growth rate. With more intensive and stable production, Krüger Kaldnes
offers cost-effective systems for CO 2
stripping and aeration.
Effluent water treatment from fish farms and abattoir waste
Wastewater from fish farms and production plants constitutes pollutants that may harm the receiving water
resources. Treatment of discharges is hence often a necessity to ensure sustainability of fish production facilities.
Effluent treatment will typically constitute processes for removal of major pollutants such as organic matter,
suspended solids, ammonia nitrogen and bacteria/virus. Krüger Kaldnes offer a wide range of treatment solutions
for these objectives. Typical unit processes may include:
> Biological treatment
> Solids removal
> Disinfection
The Moving Bed Biofilm
Reactor (AnoxKaldnes MBBR)
is our own proprietary
technology, and the biological
engine of Krüger Kaldnes RAS.
The MBBR technology allows
the microorganisms to grow
on sheltered, surfaces inside moving, plastic carriers
creating a continuous biofilm process without any risk
for clogging and without any need for back flushing.
Advantages like low head loss and high volumetric
capacity make the process compact and well suited
for treatment of large water flows. The process is very
robust and easily operated with a minimum need for
maintenance.
Biomass from the AnoxKaldnes
MBBR process, fish faeces
and excess feed is efficiently
separated with Hydrotech drum
filters, another well known
Veolia Water Solutions &
Technologies’ technology in
the industry.
The Hydrotech TM filters have a high hydraulic capacity,
are easy to operate and provide a predictable result.
Typical mesh sizes are 40-90 micron, but can be
delivered with mesh sizes down to 10 micron.
Sludge treatment
Sludge and waste from fish farm facilities typically comprises biomass from biological treatment, fish faeces, feed
waste, dead fish and abattoir waste. Krüger Kaldnes offers solutions for:
> Storage
> Stabilization
> Hygienization
> Dewatering
Krüger Kaldnes has developed a range of concepts for sludge handling at fish farms and fish processing sites. The
different systems are adapted to each individual site based on quantity and quality of raw sludge, local regulations
and transportation- and end user requirements. All of Krüger Kaldnes’ sludge treatment systems focus on high
quality, low energy and simple operation with low requirements for maintenance.
Other processes provided in Krüger Kaldnes RAS plants may
include oxygenation, ozonation, UV disinfection, CO 2
removal,
N 2
removal and alkalinisation. Krüger Kaldnes RAS provides
highly compact and energy efficient solutions with focus on
easy operation and low maintenance requirements.