This document discusses trends and opportunities in wastewater treatment in the Netherlands over the next 60 years. It focuses on closing water, nutrient, and energy cycles by making wastewater treatment more sustainable. Key areas of focus include recovering nutrients and energy from wastewater, reducing energy usage, reusing water, and developing decentralized treatment methods. New treatment concepts like energy factories that integrate nutrient recovery and energy production are presented as ways to meet changing policy goals around water quality, energy reduction, and climate change.
2. Wastewater in The Netherlands
• Production almost 2 billion m3 clean effluent per year
• Originating from industry and approximately 7.2 million
households
• Treated in 350 WWTP’s
• Electricity use of 0.37 kWh/m3 treated wastewater
(but heating of water 60 Mjprimair/m3)
• 15-20% of imported phosphate rock ends up in wastewater
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3. Wastewater treatment focus;
changes in the past 60 years
Removal of organics,
Nitrogen and phosphate
Multifunctional
Area use
Removal
3 of Organics
4. Is this enough?
• Water Framework Directive (WFD-EU)
• Changing focus to more “sustainable” wastewater treatment:
• Grey water, black water and rainwater treatment;
• Less energy use + energy recovery;
• Wastewater as source
Possibilities & limits
of the activated sludge
process
STOWA 2007
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5. 5
Changes in the next (60) jaar?
(waste)(water)chain
ery
co v
t re
rien
Nut
N P
New E&Q
sanit
P atio n
Product formaton W
N pro aste
ces
sin
g
Sewer management
Drinking water
purification
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6. Demand driven research?!
Commitments of the waterboards:
• Water Framework Directive EU
• Good ecological status surface water (Nutrients, Micro Pollutants,
metals, EDC’s, pharmaceuticals etc.)
• Reduction energy consumption
• 2% / year (2005-2020: 30%)
• Climate agreement with the National Government, March 2010
• 40% sustainable energy production in 2020
• 30% reduction GHG 1990 en 2020
• 100% sustainable purchase
• Green deal, October 2011
• 12 Energy factories + 5 Phosphorus recovery plants
• Covenant Phosphorus Cycle, October 2011
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7. Themes for the coming years
Energy recovery
Nutr
i
reco ent
very
re u se
a ter
W
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8. Roadmap 2030 – “sources-factory”
Water
Nutrients
Energy
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9. Water
Water reuse Nutrients
Energy
Important characteristics for WWTP configuration
• Physical removal of COD
• Biological removal of N
• Biological and chemical/physical removal of P
• Biological processes based on activated sludge
and attached growth (membrane, sand filters,
activated carbon).
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10. Projects
• Irrigation in greenhouses Water
• Pilot at Harnaschpolder with filtration methods;
• Sewermining
Water
• Production of high quality process water from sewer,
preferably energy neutral Energy
• Anaerobic Membranes
• uncoupling HRT and SRT, resulting in high quality nutrient Water
rich, pathogen free effluent;
• Fouling, shear and costs Nutrients
Energy
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11. Water
Nutrient recovery Nutrients
Product recovery
Energy
Important characteristics for WWTP configuration
• Separate nutrients and COD
Nutrients
Energy
• Concentrate nutrients (precipitation)
• Recover other products or produce products (bioplastics, other
polymers, fine sieve material, algea?, duckweed?)
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12. Chances for decentralized treatment
or different wastewater collection
Grijs water
Grey water Grey water
Grijs water
Feaces;
3,4% Urine; 47% 18%
11,6%
Nitrogen
Phosphate
Feaces;
12 Urine; 85% 35%
13. Water
Energy production Nutrients
or Energy-factory
Energy
Important characteristics for WWTP configuration
• Separation of COD instead of aerobic degradation
(optimization biogas production and energy consumption at
aeration)
• Energy: economic removal of N, P and residual COD
(anammox)
• Maximal recovery of sludge caloric content
Chances for heat recovery in the sewer
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15. Research topics
formulated by the waterboards
treatmentconcept (11)
Separation solids and water
Separation C and N treatment
Rejectionwater treatment
Small WWTP’s
Low energy technologies
Sludge treatment (5)
Optimalisation digestionproces
Alternatives digestion
Co-digestion
Final sludge treatment
Energyconversion, -supply (7)
Energy conversion
Energie supply
Heat from watercycle
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16. Role of Anammox in the E-factory
Based on:
Lower COD for N-removal (denitrification)
more COD for biogas production
Rejection Water
“Anammox brings WWTP closer to energy
autarky due to increased biogas production and
reduced aeration energy for N-removal” Sewage
Siegrist et al., 2008 “Sewage treatment with Anammox”
Kartal et al., 2010 - Science
Revival of the A/B system:
Lower COD for N-removal (Anammox in the B-stage)
more COD for biogas production
(Biomass production in A-stage)
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17. Anammox technology at low temperatures
(Paques, TUD, RUN, WSHD, STOWA)
Main concern:
Competition ammonium and nitrite oxidizing
bacteria and Anammox at pilot (and full
scale) conditions
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18. Combining old and new goals
Aerobic granular sludge technology:
Excellent settling properties sludge
Granules without carrier material
High biomass concentrations
Activated sludge Extensive nutrient removal
Aerobic Granules Low area requirement
Simple single-tank concept
Sustainable (energy and additives)
Low costs
Water
???!
Nutrients
Products Energy
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19. Example of technology development
Successful cooperation needed,
In this Nereda Case:
University (TUD), Industry (DHV)
and Government (waterboards, stowa, stw, EU)
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Waterschappen produceren 80 miljoen kuub biogas/jaar (7,2 milj huiushoudens, bijna 2 miljard m3 afvalwater/jaar, 24 miljoen i.e., 0,37 kWh/m 3 electriciteitsverbruik (ong 3,5 maal zoveel voor verwarmen water), ongeveer 50 kWh/m3 drinkwater zuivering en transport en 0,11 kWh/m3 voor riooltransport 15% van de geinmporteerde fosfaat eindigt in het rioolwater (6 kg pp import: 0,9 kg/j pp in rioolwater)