Download Ernő Fleit

Focus on Lead Markets:
Waste and Recycling
Wastewater Treatment
Ernő Fleit
Associate Professor
Department of Sanitary and Environmental Engineering
Budapest University of Technology and Economics
Hungary
Problem exposition
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Do we know enough from our solid and liquid
wastes (wastewater)?
To meet standards – yes
For sustainability and lead market objectives –
probably not
Key issues on waste management
High-tech (generation) low-tech (waste
management) dilemmas
Virtually no old concepts exist
New ideas in old environment – urban cycles
New Directive on waste
(EU Directive 2006/12/EC)
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Waste hierarchy
 Reduction (prevention of generation)
 Re-use
 Recovery (recycling, composting, energy)
 Disposal
Waste management cycle
Waste management options
Mechanical/biological treatment
AIM: Improvements on landfill operation
 Reduction of waste volume to be
landfilled
 Reduction in emission potential
 Facilitation of landfill operation due to
reduced emissions
 Reduction in leachate collection needs
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Mechanical/biological treatment
scheme
Considerations of dumping grounds
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Mass balance for aerobic treatment
Considerations of dumping grounds II.
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Mass balance for anaerobic treatment
Intermediate conclusions I.
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No unique solution exists – as criteria vary
Technical
 Financial
 Environmental
 Social
 Institutional
 Political
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Intermediate conclusions II.
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Selection of appropriate technology:
Volume of waste
 Waste composition
 Market for secondary products if any
 Authority and social priorities
 Volume of residual material (available landfill)
 Investment and operational cost
 New challenges
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Nanotechnology – the promise
(nanomarket growth to 1 trillion € over
the next 10 years)
Fields of application potential:
 Membrane filtration (drinking and
wastewater)
 Anti-microbial nanoparticles for
disinfection and microbial control
 Removal of arsenic and heavy metals
 Nanosensors for water quality monitoring
Nanotechnology – a cautionary note
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Risk – toxicity and exposure
Nanoexposure studies – only on inhalation
Aquatic environment ?
Time-lag (see also DDT history)
Safe particles
Biological wastewater treatment
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Suspended cell bioreactors
(activated sludge systems)
Particle size distribution
Diffusion limitations
Ratio of floc and filament former
bacteria
Technological functions
A novel concept – IASON
(developed by the BME)
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O –
N -
Intelligent
Artificial
Sludge
Operated by
Nanotechnology
An example:
the Bardenpho
IASON process
control
process
Raw
wastewater
Treated
effluent
Anaerobic
Anoxic
Oxic
Wastewater bacteria on microscopic carrier
materials (PVA-PAA)
A
100 m
Challenges for wastewater treatment
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Adoption to changes in ever changing
wastewater composition
New type of pollutants (EDS materials)
Conceptual change and novel opportunities
Professional background (R+D and
education)
Design of wastewater composition
Conceptual change needed
URBAN UREA CYCLE
The problem itself
N removal
NH4+
30 g/cap/d
Nitrification (oxidation to NO3-)
Denitrification (reduction to N2)
The problem in numbers
In Budapest the annual carbamide release via urine is
22,000 tons (30 g/cap/d)
 Market value: 2,2*109 HUF (9,1 Million €/y)
 Yearly expenditure on N removal 5,5*109 HUF (22,7
Million €/y)
(0,5 Mio m3/d wastewater and 30 HUF/m3 N removal
cost)
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These all together: 7,7 billion HUF/y (31,8 Million
€/y)
What separates us from this money ???
Wastewater composition „design”
for carbamide (2 problems)
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Inhibition of carbamide degradation
Removal of urea from wastewater prior to
reach WWTP/or at the head of WWTP
Removal of urea from raw wastewater
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Microfiltration (should precipitable product is
formed)
Ionic exchange (charged molecule)
Simple adsorbers (if polymer)
Sedimentation (if formed precipitate is large and
dense enough)
FINAL RESULTS: greatly decreased N load in raw
wastewater (savings on O+M cost) and marketable N
fertilizer (carbamide)
FINAL CONCLUSIONS
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The classical period of wastewater treatment
technology is over (LCA, EDS, cost,
sustainability)
We must not keep the usual distance from our
wastewater (e.g., Singapore – NEWater,
reclaimed water)
The raw wastewater has to be considered as a
valuable product (energy contents: MFC, biogas
production), marketable compounds (carbamide)
Source control (EDS materials)