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Membrane Life and Replacement Market
- Our Experience in Europe -
1998 - 2008
Mito Kanai
Kubota Membrane Europe
IWA Regional Conference
Membrane Technologies in Water and Wastewater Treatment
MOSCOW, 2-4 June, 2008
1. Who we are
2. Types of MBR Projects
3. Reasons of Membrane Replacement
4. Key to the Future Replacement
Outline
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1.Who we are
• Consolidated Japanese membrane manufacturer
• Tradition in Environmental Tech (products & services)
• Excellence & worldwide brand reputation
KUBOTA CORPORATION
Founded in Japan, 1890
23,700 employees
Turnover: US$ 9.4 Billion
Water Related Turnover: US$2.1 Billion
(as of March 31st 2007)
Our focus
• Engineering-focused company
Sales staff are engineers involved in product development
• Less focus on marketing
“Let the products speak for us”
• Long-term relationships with customers
Crucial in the high-tech low-volume market segment
• Focus on MBR technology above all
Committed to efficient wastewater treatment to meet highest standards
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Our position
• Global deployment
• Local reach through engineering partners
• Longstanding feedback from end users
• Enhanced Experience Exchange through Global
Partners’ Meetings
• Pre-sales and Post-sales support
• (Service contracts)
Pioneers in MBR FS membrane technology, leaders with
>2,500 installed references worldwide
Global Network with local reach
Only in Europe region, the Kubota family has:
Commercial, Technical & Logistic support centre in London
12 partner companies
60 field sales staff
30 proposal engineers
20 commissioning engineers
15 process scientists
References in 17 countries
274 plants (126 municipal) as of 2007
300,000 m3/d treated
700,000 Cartridges installed (560,000 m2 filtration area)
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Our MBR concept
Membranes not only contribute to solid/liquid
separation but also the air from membrane diffusers
partly or in some cases wholly supply the oxygen
amount required to remove nutrients.
Evolution
Aeration needs: m3 air/ m3 perm.
EK series 30% less than ES series
EW series up to 68% less than ES series
Weight of module: kg/m2 membrane
ES/EK v2008 17% less than v2006
RW 30% less than ES/EK v2006
Economies of scale:ES
EK
RWFootprint: m2 mem/ m2 footprint
EK series 50% less than ES series
RW series up to 80% less than ES series
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2. Types of MBR projects
1. New ‘stand-alone’
2. New hybrids
3. Upgrades of aging conventional plants (Retrofits)
4. Upgrades of existing MBR plants
5. Part membrane replacements
6. Whole membrane replacement
Membrane Replacements
• 19 out of 232 projects had required spares
• 25% of the spares were for municipal projects
•
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Parameter Value
FFT 1907 m3/d
Average flow ~900 m3/d
Peak hourly flow 22 l/sPopulation equivalent (PE) 3800 (summer)
2600 (winter)
Number of tanks 4
Number of modules 24
Type of module A150
Total number of panels 3,600
Flux at FFT 0.65 m/d (27 lm-2h-1)
Flux at average flow 0.31 m/d (13 lm-2h-1)
Plant start-up date Feb1998
Porlock STW, UK
Consent: BOD:SS:Turbidity 40:60:30
Performance: 5:1:1
Case study 1: Porlock STW
• 9 years continuous operation on12th Feb 2007
• Snags from 1998 and Some progress- Inlet screens 3 mm, + new in-line 2 mm perforated D screen installed(then, was stopped due to splashing)
- Site drainage bypass now captured with new screen (then stopped due to the stoppage of 2nd screen operation)
- Screenings removed, membranes given full overhaul in 2006- Flow split chamber still poor but better with ‘temporary’ fix (Dec 05)- Transfer sump flows to be increased to improve flow split (pump failed)
- Blower failures a problem more reliable, one still undersized- No grit removal! But all accumulated grit in tanks removed 400 mm deep in year 8!
- Membrane unit brackets being installed
Site condition - history
Case study 1: Porlock STW
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Durability
230 membranes replaced out of 3600 after 10 years
(~ 94 % originals, 187 replaced in year 8)
Permeate tubes were replaced in year 3 to remove
internal tube connectors. All tubes were replaced at
year 8 overhaul
Porlock STW Membrane Condition
SEM image of Porlock
membrane after 2h 0.5%
NaClO clean, Mar 2008
Before washed by water After washed by water
Reasons of Replacements
Holes from debris and grit
55%Internal
sludge or contamination
inside (probably
small holes)24%
Mishandling11%
Seals torn or split 6%
Removed in error
(cleanable staining)
4%
Porlock STW 1998 – 2006
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ReliabilityJune 1998 – September 2001, Porlock STW
Kubota Submerged Membrane Process
Case Study 2: Paper Mill
Buffer Tank
500 m3
Aeration tank
1610 m3
Deep Water
7 m
Membrane
Tank
2 x 200 m3
Recirculation
3 * inflow
Permeate
Pumps
Sludge Buffer
Tank 200 m3
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Case Study 2: Paper Mill
Activated
sludge tank
Buffer
tank
Air blower
Treated water
Immersed membrane
units
Sludge extraction Aeration
Raw water
Nutrients
Lift pump
Agitator
Screening
(1 mm)
Membrane tanks
Case Study 2: Paper Mill
Design parameters :
> Max daily flow : 1300 m3/d
> Average daily flow : 900 m3/d
> COD / BOD5 = 1,9 (biodegradable effluent)
Parameters Inflow Outflow
BOD5 (mg/l) 1846 100
COD (mg/l) 3500 600
TSS (mg/l) 269 100
Nitrogen (mg/l) 40 30
Phosphorus (mg/l) 2
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Case Study 2: Paper Mill
Calcium in Inflow caused very high fouling rate
Sep 2004: Operation mode adapted to the amount of calcium
2005: Calcium load reduced by dilution
2007: Change in Mgmt + Service Contract not renewed
2007: Severe calcium precipitation and membrane damage
2008: 50% of membranes replaced after 4 years of operation.
Period Calcium (mg/l)
2004 1 200 to 1 400
2005 - 2006 280 to 400
2007 500 to 1 700
Case Study 2: Paper Mill
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After classical chemical cleaning (acid, chlorine) Clear water
permeability : 96-100% of new membrane performance
MEMBRANE ANALYSIS AFTER 3.5yrs OPERATION
Operation conditions: Calcium up to 1 700 mg/l, frequent acid and
chlorine cleans
No damage on the membrane surfaceNo weakness on seams
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Case Study 2: Paper Mill
Laure Renvoisé (STEREAU) & Thomas
Wozniak (Nalco)
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2004 – 2005
Stable TMP 75 mbar
Flow 17 lmh
with NaOCl
cleaning/year
2006
Unstable TMP
14 lmh
1 NaOCl cleaning
/month
Case Study 2: Paper Mill
Calcite deposition seen on the
out side of membrane units.
Calcites precipitated inside the
permeate tubes.
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Case Study 3: Emergency Replacements
Replaced FS competitor in Spain municipal plant
after 1 yr operation
4 x ES200 without design modifications
Replaced HF competitor in
Japanese industry
12 x EK300 plug & run,
non-stop
Replaced HF competitor in Benelux industry
8 x RW400
Very short delivery conditions
Membrane Life
• Membrane performance and integrity dictate Membrane
Life (Related to Flow and SS in effluent, respectively)
• Membrane Life largely depends on O&M. We will
contribute to Operators’ Workshop in Europe to
exchange O&M information and experiences.
• Membrane Performance: Porlock maintained 0.65 m/d
(22 lmh) flux with 100 mm headloss over 10 years
• Membrane Integrity: Integrity loss by operational
mistake or sudden influent change can be the greatest
factor responsible for shorter-term replacement
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4. Key to the future replacement
• Price Commitment Option from the
manufacturer to the customers who would like
to prepare for the future replacement
• Plant Monitoring Option by Service ContractMonitoring the membrane performance and advise the customers when
the membrane replacement is necessary by carrying out tests.
4. Key to the Future Replacement
• Quick delivery & installationThe end-user wants “Next day” membrane delivery
once decided to purchase the membranes.
• Before replacement, it is best to solve other
problems to avoid the “NEW membranes do not
perform expectedly ” and avoid Next
Replacement in short-term – Membranes are
not the problem!
• WLC calculation would help to prepare for
future replacement
Even if the plant is maintained well, every plant faces replacement
(If the plant is NOT well-maintained, replacement comes even more quickly!)
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Cпacибo!
Please visit our booth at
ECWATECH A116
Kubota Membrane Europe Ltd.
3rd floor, No. 1 Farriers Yard
77 Fulham Palace Road
London, W6 8AH, UK
www.kubota-mbr.com
Tel.: +44 (0)20-8741 5262
Fax.: +44 (0)20-8563 1616
http://www.kubota-mbr.com/
