Date post: | 27-May-2015 |
Category: |
Technology |
Upload: | delft-urban-water |
View: | 800 times |
Download: | 0 times |
1
Closing Water, Nutrient and Energy
cycles
Starting in wastewater treatment systems…
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
3
Wastewater treatment focus;changes in the past 60 years
Removal of Organics
Removal of organics, Nitrogen and phosphate
MultifunctionalArea use
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
processSTOWA 2007
5
5
Drinking water purification
N P
P
NProduct formaton
Changes in the next (60) jaar?
E&Q
Wasteprocessing
Nutrient re
covery
Newsanitation
Sewer management
(waste)(water)chain
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
7
Themes for the coming years
Water reuse
Nutrientrecovery
Energy recovery
8
Roadmap 2030 – “sources-factory”
Water
EnergyNutrients
9
Water reuseWater
EnergyNutrients
Water
EnergyNutrients
Water
EnergyNutrients
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).
10
Projects• Irrigation in greenhouses
• Pilot at Harnaschpolder with filtration methods;
• Sewermining
• Production of high quality process water from sewer, preferably energy neutral
• Anaerobic Membranes
• uncoupling HRT and SRT, resulting in high quality nutrient rich, pathogen free effluent;
• Fouling, shear and costs
Water
Energy
Water
Energy
WaterWater
Water
EnergyNutrients
Water
EnergyNutrients
Water
EnergyNutrients
11
Nutrient recoveryProduct recovery
Important characteristics for WWTP configuration
• Separate nutrients and COD
• Concentrate nutrients (precipitation)
• Recover other products or produce products (bioplastics, other polymers, fine sieve
material, algea?, duckweed?)
EnergyNutrients
EnergyNutrients
Water
EnergyNutrients
Water
EnergyNutrients
Water
EnergyNutrients
12
Chances for decentralized treatmentor different wastewater collection
Feaces; 35%
Urine; 47%Grijs water
18%Grey water
Urine; 85%
Feaces; 11,6%
Grijs water 3,4%
NitrogenGrey water
Phosphate
13
Energy production or Energy-factory
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
Water
EnergyNutrients
Water
EnergyNutrients
Water
EnergyNutrients
14 www.energiefabriek.com
• Realisation• Research/development
• Marketing
15
Research topics formulated by the waterboards
treatmentconcept (11)Separation solids and waterSeparation C and N treatmentRejectionwater treatmentSmall WWTP’sLow energy technologies
Sludge treatment (5)Optimalisation digestionprocesAlternatives digestionCo-digestionFinal sludge treatment
Energyconversion, -supply (7)Energy conversionEnergie supply Heat from watercycle
16
Role of Anammox in the E-factory
Sewage “Sewage treatment with Anammox”
Kartal et al., 2010 - Science
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”
Siegrist et al., 2008
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)
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
18
Combining old and new goalsAerobic granular sludge technology: Excellent settling properties sludge Granules without carrier material High biomass concentrations Extensive nutrient removal
Low area requirement Simple single-tank concept Sustainable (energy and additives) Low costs
Activated sludge
Aerobic Granules
Water
EnergyNutrients
Water
EnergyNutrients
Water
EnergyNutrientsProducts
???!
19
Example of technology development
Successful cooperation needed,In this Nereda Case:University (TUD), Industry (DHV) and Government (waterboards, stowa, stw, EU)
20
Questions?