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Membrane filtration plants
NOKA delivered its first membrane filtration plant in 1995 and since then has delivered appox. 20 membrane filtration plants. In recent years, the majority of our work in connection with membrane filtration plants has involved rehabilitation, i.e. :
- New membranes
Of various types, depending on raw water quality and water quality standards to be met
- New pressure pipes
Expanding capacity to supply purified water
- New PLS
More user friendly and spare parts more easily obtainable
- New pre-filter
Improved pre-treatment
- New circulation pump
Improved potential for self-cleaning
- Rebuilding of pipe work
Process modification
- New instruments
More user friendly, improved reliability
- UV purification unit
An additional hygienic barrier
NOKA undertakes all kinds of rehabilitation work on membrane filtration systems, irrespective of original supplier.
Since 2003, NOKA has delivered/entered into contracts for nearly 10 new membrane filtration systems.
Of these new membrane filtration systems, two are ultrafiltration systems. This is an exciting and innovative type of membrane filtration system that is widely used in Europe and elsewhere in the world.
We are proud to have delivered Norway's first full-scale drinking water ultrafiltration plant with a purification capacity of 12,000 m3/d.
The table below compares the two membrane filtration concepts most commonly used in Norway for drinking water treatment.
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Ultrafiltration
(Dead-end)
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Nanofiltration (Crossflow)
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Flux [L/m2*h]
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80
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15
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Operating pressure [Bar]
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0.2-0.8
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4-6
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Energy consumption
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Low
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High
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Estimated membrane life [years]
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10 years
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10 years
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Guaranteed membrane life
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5 years, pro rata
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1 year
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Degree of recycling
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>90
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70-77
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Pore size [nm]
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10
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2
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Max turbidity [FTU]
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<50
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1
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Permissible pH zone, operation (cleaning)
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2-13 (2-13)
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3-7 (2,5-8,0)
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Removal of colour?
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YES,
with addition of PAX
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YES
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Hygienic barrier?
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YES
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YES
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Maintains pressure line?
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YES
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NO
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Automatic integrity testing?
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YES
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NO
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Chemicals used for operation
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PAX,
lye and chlorine
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Rinsing agent
and chlorine
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NOKA has long and comprehensive experience of the operation and design of membrane filtration systems.
Central to our strategy and vision is the delivery of crystal clear water as widely as possible, using the purification technology at our disposal. Our goal is to be a company whose customers are as satisfied with our technical solutions as with the experience of working with us.
We believe this to be confirmed by all our referees for membrane filtration plants. Please contact us for our list of referees - we are proud of it!
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