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Dr. Hermans 1 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Meeting EU regulations ….
70 - 801070-8015Total nitrogen **
801802Phosphorus **
903590 (70)35 (60)Suspended solids
7512575125COD
70 - 902570 - 9025BOD5
[% reduction][mg/l][% reduction][mg/l]
> 100.000 P.E. > 2000* - 100.000 P.E.Parameter
* Coastal water > 10.000 p.e. ** Sensitive areas, one or both parameters
Biologicaltreatment
More stringent treatment
Directive 91/271/EEC
Dr. Hermans 2 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
....easily by using Oxygen, Ozone or Carbon dioxide in water treatment
Neutralisation of industrial waste water: CO2
Prevent corrosion in canalisation and in treatment plant : O2
Capacity increase in activated sludge process: O2
Cracking of persistent COD with ozone: O3
Remediation of surface waters: O2
Dr. Hermans 3 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Neutralisation of alkaline waste waters
pH 1 pH 7 pH 14
acid neutral alkaline
Effluent discharge legislationin Europe: 6,5 < pH < 9,5
Dr. Hermans 4 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
epp 0200/9/1
CO2 consumption
Phase I
dischargelimits
Phase IIImineral acid
CO2
pH
2 OH_ + CO2
2 HCO3_
CO32_ + CO2 + H2O
CO32_ + H2O
Phase II
Neutralisation curves of mineral acid and CO2
Dr. Hermans 5 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Characteristics of CO2 and mineral acids
HCl & H2SO4
• strong acids difficult regulation
• difficult to storeand handle
• release of noxious fume• corrosion• consent levels for discharge
CO2
• week acid, no over-acidification
• storage and handling simple and safe
• inert gas• no corrosion• no salting up, ecologic
Dr. Hermans 6 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
CO2 injection in waste or process water
Pumped tube reactor with static mixer *Pumped tube reactor with multiple loops *Gas-liquid injector nozzles dH > 40 oDiffusers Pressure vessel Submerged aeratorsHose mats
* suited for injection of liquid CO2
Dr. Hermans 7 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Neutralisation of alkaline waste water with CO2
Dr. Hermans 8 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Compact units for gaseous CO2
50 kg/h CO2 75 kg/h CO2
Dr. Hermans 9 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Advantages of Neutralisation with CO2
Safe and simple pH control, overdosing not possibleLow investment costs No impact on salt content; reduced discharge feesAvoids corrosion problems when recycling effluents
Dr. Hermans 10 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
CO2 Neutralisation References
• Beverage industry
• Dairies
• Pulp & Paper Mills
• Textile industry (Leather!)
• Galvanic processes
• Concrete handling
Dr. Hermans 11 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Oxyduct: Oxygen addition in sewersPrevents sewer corrosion and hydrogen sulphide emissions
Dr. Hermans 12 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
0
2
4
6
8
10
12
0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9
Pipe Diameter [m]
Oxy
gen
dem
and
[kg/
h*10
00m
]Calculated oxygen demand for pressurized sewersAfter Lohse 1987, ATV M 168
Dr. Hermans 13 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Oxygen injection through socket
Dr. Hermans 14 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Oxygen injectionwith pump-venturiin bypass
In Budapest
Dr. Hermans 15 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Advantages of oxyduct process with oxygen
Proven technology
High oxygen solubility
Small gas flow compared to air
Economic compared to nitrate and hydrogen peroxide
Fast reaction compared to nitrate
Dr. Hermans 16 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Pure oxygen increases capacity and saves energy
Messer offers• Re-engineering of activated
sludge process• Retrofitting• Oxygenation systems• Gas supply• Coached start-up
BIOX-Process: first application at the WWTP ´Emschermündung´in 1980. Since then our technology has been introduced in over
150 plants.
Dr. Hermans 17 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Ct
Cs- air
Cs- Oxygen
* i.e. set point 2 mg/lunder atmospheric conditions
0 10 20 30t [°C]0
2*
10
20
30
40
50
60
70
80
90
C [m
g/I]
Solubility of air and Oxygenin water
Oxygen mass transfer rate is one of the main factors influencing the performance of the activated sludge process.
Power of mass transfer is pro-portional to saturation deficiency: “Cs – Ct”
Dr. Hermans 18 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
epp 0200/9
Oxygen bulk vaporizer controlstorage tank system
activated sludge basinaeration
pure oxygenpure oxygenOxygen probe
fine bubbles of oxygen are introduced over a wide area through specially developed oxygenation hose
BIOX Process
Dr. Hermans 19 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
WWTP Ilsfeld (D): increased loads from textile industry
Dr. Hermans 20 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
WWTP Beggen (Lux): Peak loads from a dairy
Dr. Hermans 21 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
WWTP Leer (D): 120.000 P.E.Deep shaft operated with pure oxygen; Waste water 50 % municipal and 50 % oil mill
Dr. Hermans 22 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
WWTP Leer: 120.000 P.E.
Deepshaft operated withpure oxygen
Increases capacity
Saves energy
Dr. Hermans 23 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Fillmixing, aeration
COD degradationNitrificationaeration, mixing, oxygenation
Denitrificationmixing
Sludge separationsedimentation
Effluent drawSurplus sludge withdrawal
Industrial waste water
Sequencing Batch Process
Dr. Hermans 24 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Sequencing Batch ReactorsOxygen Demand Profile
Time [minutes]
Oxy
gen
flow
[m3 /h
]
Oxygenation, D.O. controlled
Fill1h,10min
7 h 00min Sedimentation2h 20min
Draw1h 10min
Dr. Hermans 25 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Sequencing Batch Reactorsoxygen for cycle start in a dairy
Dr. Hermans 26 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
High rate SBR plant for treatment of sludge liquor
Advantages of the oxygenprocess•Low investment costs•Flexible operation mode •optimised sedimetation of sludge
WWTP Lingen (D)
Dr. Hermans 27 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Aerobic selector improves sludge settling
High concentration of „easy BOD“,e.g. waste water from potato processing or soft drinks, easily causes bulking sludge.
Aerobic selector: Short residence time Very high oxygenation rate
Aerobic selector in WWTP Overward (AT)
Dr. Hermans 28 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
0
50
100
150
200
250
300
350
januaryfeb
ruary
march
april may
june
julyau
gustse
ptember
octobernovem
berdece
mber20002001
Selector operatedwith pure oxygen
Municipal + potato-processing waste waterSl
udge
inde
x[m
l/gra
m]
WWTP Hankensbüttel (D)
Dr. Hermans 29 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Membrane bioreactors
• superior effluent quality• compact treatment
exploit full potentialwith pure oxygen
Industrial waste water: membrane bioreactor
Dr. Hermans 30 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Membrane Bioreactor
additional oxygen increasescapacity by > 50 %
NH4 controlled oxygen dosageLandfill leachate treatmentHorm (D)
Dr. Hermans 31 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
epp 0200/2
Nitrogen removal : FundamentalsNitrification
nitrifyingbacteria
heterotrophicbiomass
Denitrification
NH4+
O2
NO3-
NO3-
N2
Dr. Hermans 32 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Conversion to Messer’s BIOX® N process
epp 0200/3
primary settling tank aeration tank final clarifier
before BIOX N return sludgeexcess sludge
inflow outflow
inflow outflow
Denitrification Nitrification final clarifier
Primarysettingtank internal recirculation
return sludge excess sludgeBIOX N process
Dr. Hermans 33 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Conversion to Messer’s BIOX® N process : Retrofitting
epp 0200/4
Dr. Hermans 34 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
Sewage treatment plant Neustadt a/d Weinstrasse
epp 0200/6
Outlet values of nitrogen before and after conversion to BIOX® NTo
tal i
norg
anic
N (m
g/l)
before BIOX® N
BIOX® N process
wine harvest
start-up BIOX N
limit18 mg/l
16. april 05. june 25. july 13. sept. 02. nov. 22. dec.
60
50
40
30
20
10
0
Dr. Hermans 35 / 09-05
Oxygen, ozone and carbon dioxide in waste water treatment
The BIOX process-This is how oxygen saves costs
Advantages:Increases treatment capacityFlexible operation mode Costly enlargements are avoidedReduction of yearly costsNo additional energy demandRealised at short notice