wwtp inflow parameters
TRANSCRIPT
1
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Design of Wastewater Treatment Plants
Lecture 1Introduction and
Determination of inflow parameters
Prof. Dr.-Ing. Heidrun Steinmetz
Institute for Sanitary Engineering, Water Quality and Solid Waste Management- Chair of Sanitary Engineering and Water Recycling -
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Contents of the lecture
Determination of inflow parameters (ATV-DVWK - A 198)
Microbiological processes/activated sludge process
Dimensioning of activated sludge treatment plants (ATV- A 131)
Nitrogen removal
Phosphorous removal
Dimensioning of biofilters
Sludge treatment and dimensioning of sludge treatment plants
Resource orientated systems
Anaerobic systems
Planning process
Exercise
Excursion
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Design of WWTP1. Determination of inflow parameters
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Introduction and repetition
Aim of biological Waste water treatment:Removal of carbon compounds (BOD5, COD)Reason: prevent oxygen depletion of receiving waters
Removal of nutrients (nitrogen, phosphorus) Reason: prevent eutrophication of receiving waters
WastewaterTreatment Plant Corg, NH4, NO3, PO4
Corg, Norg, NH4, Porg
Corg,Norg,Porg
CO2,N2Influent Effluent
Gas
Sludge
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Components in Wastewater and their Effects
Radioactivity
Aesthetic inconveniences, toxicity
Hydrogen sulfide, othersOdour (and taste)
Changing living conditions for flora and fauna
Hot waterThermal effects
Toxicity, corrosionAcids, bases, hydrogen
sulfideOther inorganic material
Toxicity, bioaccumulationHg, Pb, Cd, Cr, Cu, NiMetals
Eutrophication,
oxygen depletionNitrogen, phosphorusNutrients
Toxicity, bioaccumulation in the food chain,
Detergents, pesticides, fat, oil, phenols,endocrine d.....
Other organic material
Fish death, odors, deterioration of drinking w.
Oxygen depletion in water bodies
Biodegradable organic material
Risk when bathing and eating fishes
Pathogenic bact., viruses and worm eggs
Microorganisms
Environmental effectOf special interestComponent
!
!
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Design of WWTP1. Determination of inflow parameters
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Carbon (C)- Parameters for Dimensioning
COD (Chemical oxygen demand) Amount of oxygen required for the chemical oxidation of organic compounds
Specific load per inhabitant (acc. to ATV-DVWK A 131, 2000):120 g BOD5/(C·d)
BOD (Biochemical oxygen demand)Amount of oxygen required for the biological oxidation of organic compounds
BOD5: Degradation time = 5 days; Temperature = 20 °C
Specific load per inhabitant (acc. to ATV-DVWK A 131, 2000):60 g BOD5/(C·d)
Only a part of the organic wastewater constituents are readily degradable
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Phosphorus (P) – Parameter for Dimensioning
Pto
tal Po
ly-P
ho
sph
ate
/ o
rg. P
ort
ho
Ph
osp
hat
e /
ino
rg. P
Specific load per inhabitant (acc. to ATV-DVWK A 131, 2000):
1.8 g P/(C.d)
Origin (acc. to Raach et al., 1999 ):
70% Urin and Faeces
17% Washingpowder/liquid
13% Kitchen waste
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Specific Load and Concentration of Nutrients
The specific load of phosphorus decreased within the last years due to the reduction of P in detergents
The specific load of nitrogen is 11 to 13 g/(cap•d)
10.02.03.04.9Total
0.50.11.13.0Detergents
9.51.91.91.9Food
mg/L Pg/(cap•d) Pg/(cap•d) Pg/(cap•d) P
200019891985
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Design of WWTP1. Determination of inflow parameters
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Nitrogen (N) - Parameters for Dimensioning
Ng
es
TK
NN
Ox-
N
NH
4-N
NO
x-N
org
. N
Nan
org
org
. N
Specific load per inhabitant (acc. to ATV-DVWK A 131, 2000):
11 g N/(C.d)
Origin (acc. to Koppe and Stozek, 1999) :
76% Urine
14% Faeces
10% Washing and cleaning agents
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Design of WWTP1. Determination of inflow parameters
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Basic Flow Scheme of a WWTP
Secondary sludge= Excess sludge
Dewatering and-agricultural use-landfill-incineration
Primary treatment Biological treatment
Return sludge
Screenings Sand
Influent
Effluent
GreasePrimarysludge
Aerationtank
Secondarysediment.
Raw sludge
Digester35°C
Thickener andstorage tank
BiogasGas storage
Thickener
Screening Gritrem.
Greaserem.
Primarysediment.
Supernatant
Sludge treatment
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Design of WWTP1. Determination of inflow parameters
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Introduction and repetition
IndustrialWastewater
DomesticWastewater
InfiltrationWater
Preci-pitation
Combined SewerWastewater Sewer
IndustrialWWTP
StormSewer
Municipal WastewaterTreatment Plant
2,8
3,2 3,9 0,9
0,6
1,2
Billion m³/a
2,8 8,9
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Design of WWTP1. Determination of inflow parameters
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Types of Wastewater (WW)
Municipal WWDomestic or Household WW
Industrial, Commercial, Institutional WW
Infiltration WW (Imported, Sewer Infiltration, Parasite Water)
Stormwater
Average Flow treatment process design in m3/d
Peak Flow hydraulic design in m3/h;l/s
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Design of WWTP1. Determination of inflow parameters
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Determination of Dimensioning Values
Wastewater flow • Concentration = LoadWastewater flow • Concentration = Load
Can be measured !
Cannot be measured directly !
Literature values (Loads) and measured values(flow and/or concentrations) often cannot bebrought into agreement easily!
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Design of WWTP1. Determination of inflow parameters
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How to start with the dimensioning?
Which input parameters are needed?Load of BOD (or COD)
Load of total nitrogen
Load of total Phosphorous
Load of TSS
Temperature
Mean flows
Maximum flow (minimum flow)
If data do exist, one should need them
Aim of DWA A 198
Verification is always necessary (are the results plausible?)
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Aims and application of A- 198
Examination of existing data (self-monitoring, specific monitoring programms) as well as derivation of dimensioning values and forecast values for various time horizons (planning criteria)
Adjustment of dimensioning values of sewer systems and wastewater treatment plants
Harmonizing the symbols for dimensioning as extensively as possible
Mathematical determination of the dry weather flow (dissociated from meteorological records)
Approach for the determination of the combined wastewater flow (Qcomb) at the interface sewer – wastewater treatment plant
Determination of concentration of N and P on the basis of COD as a master parameter
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Design of WWTP1. Determination of inflow parameters
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Aims and application of A- 198
However:
because of the temporal variable releases of standards and leaflets there are yet much different terms and symbols for the same facts
However:
the needed flows, loads and concentrations for dimensioning are to be found in the respective standards (e.g. A 131)
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Design of WWTP1. Determination of inflow parameters
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Symbols and their meanings I
Main terms:
A = Areas [ha, m²]
Q = Flows [l/s, m³/a, m³/d, m³/h]
C = Concentrations (homogenised sample) [mg/l, kg/m³, %]
S = Concentrations (filtered sample) [mg/l, kg/m³, %]
X = Concentrations (in the filter residue) [mg/l, kg/m³, %]
B = Loads [kg/a, kg/d, kg/h]
q = Flow rates [l/(s ha)]
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Design of WWTP1. Determination of inflow parameters
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Symbols and their meanings II
Indices
Catchment areas
Types of flow
Periods of time
Mean values for periods
Parameters
Location of sampling
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Symbols and their meanings III
Catchment Areas (AC)
Area with seperate sewer system (AC,Sep)
Area with combined sewer system (AC,Comb)
Paved surface (AC,p)
Non-paved surface (AC,np)
With sewers (AC,s or e.g. AC,s,p)
Types of flow (Q)
WW - wastewater flow (QWW)
DW - dry weather flow (QDW)
Inf - infiltration water flow (QInf)
Comb - combined wastewater flow (QComb)
Thr - throttle flow (QThr)
Mean values for periods
aM – annual mean
mM – monthly mean
pM – mean for a period
wM – weekly mean
2wM – 2-weekly mean
dM – daily mean
hM – hourly mean
With no details:
intervall < 5 minutes
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Design of WWTP1. Determination of inflow parameters
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Symbols and their meanings IV
Periods of time
a, m, w, d, h, min
P a special period
Location of sampling
In – inflow to thewastewater treatmentplant
InB – inflow to the biologicalstage
ESST – effluent of thesecondary settlingstage
EF – effluent of a filter
EP – effluent of a pond
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Definition of the types of areas
AC
AC,ns
AC,s
AC,p
AC,np
Sou
rce:
AT
V-D
VW
K-S
tand
ard
A 1
98 (
2003
)
Catchment Area
Catchment area notserved by sewers
Catchment area servedby sewers
Paved surface
Non-pavedsurface
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Design of WWTP1. Determination of inflow parameters
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Symbols and their meanings V
QDW Dry weather flow l/s
QComb Combined wastewater flow to the wastewater
treatment plant l/s
Qa Annual flow m³/a
Qd Daily flow m³/d
QDW,d Daily dry weather flow m³/d
QDW,d,aM Dry weather flow as annual mean m³/d
(quotient of sum of daily flows of all dry weather
days and the number of dry weather days of a year)
QDW,aM Dry weather flow as annual mean l/s
QDW,2h,max Maximum dry weather flow as 2-hourly mean m³/h
QSl,d Daily volume of sludge m³/d
QWS,d Daily volume of waste (activated) sludge m³/d
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Determination of Dimensioning Values
It should be differentiated between the actual loading (status quo) and the designed loading (predicted)
It should be differentiated between:
Water quantity
Loads
Concentrations
Several sources are used:
Existing measurements
Operations manual
Special monitoring programs
Operation of experimental plants
Data from municipalities, industries and others
Literature values
Empirical values, estimates
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Design of WWTP1. Determination of inflow parameters
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Actual situation and prognosis
Infiltration waterInfiltration water
Industrial wastewaterIndustrial wastewater
QD,dwdPQD,dwdP
Domestic wastewaterDomestic wastewater
PrognosisActual situation
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Dimensioning Values
Flow data
Mean values (for procedural design)
QDW,d Daily dry weather flow m³/d
QDW,aM Dry weather flow as annual mean l/s
Peak values (for hydraulic calculations)
Important for complete optimization of sewer and wastewater treatment plant!!
In catchment areas only with separate sewer system
QDW,h,max
In catchment areas with combined sewer systems
QComb
Additional for hydraulic calculations the Minimum dry weather flow as 2-hourly mean
QDW,2h,min
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Dimensioning Values
Design of the primary settling tanks
Dry weather flow
QDW,2h,max
Stormwater flow
Combined sewer system: QComb
Separate sewer system: QR,Sep,h,max
Operational temperature
Lowest temp. (for process design)
Highest temp. (for design of aeration system)
Temperature at location of sampling: effluent of the biological tank (alternatively inflow or effluent of the primary settling tank)
Relevant: Determination from the curve of 2-week mean over 2 years
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Design of WWTP1. Determination of inflow parameters
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Annual temperature variation WWTP H. 2006
0
5
10
15
20
25
J F M A M J J A S O N D
Months
Tem
per
atu
re i
n °
C
Daily temperature
2 weeks mean
12 °C
10 °C
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Design of WWTP1. Determination of inflow parameters
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Dimensioning values for wastewater treatment plants
Loads and concentrationsClassification of wastewater treatment plants in size ranges
BOD5 load(Bd,BOD5,In)in the influent to the wastewater treatment plant which is undercut on 85% of the dry weather days without backflows plus a planned capacity reserve.
Calculation out of minimum 40 values of BOD5 loads out of 3 years
Dimensioning of combined sewer overflows
Annual mean value of the COD concentration in the inflow to the wastewater treatment plant
Dimensioning of wastewater treatment plants
Relevant loads for dimensioning the biological reactor
Bd,COD,InB kg/d
Bd,BOD5,InB kg/d (also for trickling filters)
Bd,SS,InB kg/d
Bd,TKN,InB (evtl.: Bd,NO3,InB and Bd,NO2,InB) kg/d (also for trickling filters)
Bd,P,InB kg/d
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Dimensioning of activated sludge plants according to A131
The relevant loads are calculated as
The maximum 2-4-weekly means in the determining range of temperature
or
85-percentile value of minimum 40 daily loads that are uniformly distributed over up to 3 years
Attention: If an annual graph indicates periodical fluctuations, several loading cases are to be investigated.
Relevant sludge volume index (SVI)
Maximum value of 3 year curves as 2-week mean
or
85%-percentile value of the last 2 years
Peak factor
Maximum daily 2-h-load/ daily average
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Design of WWTP1. Determination of inflow parameters
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Daily Variations of Wastewater Flow
Determination of yearly wastewater flow (sewage flow on all days)
Determination of yearly dry weather flow (dry weather flow on dayswithout rain)
Determination of peak flow during dry weather
iqC,iAWW,dwP
WW,aMQ ⋅+⋅
=86400
Inf,aMQ
WW,aMQ
DW,aMQ +=
Inf,aMQ
Qx
WW,aMQ
DW,Q +
⋅=
max
24
maxSou
rce:
AT
V-D
VW
K-A
rbei
tsbl
att A
198
(A
pril
2003
)
[ l/s ]
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Daily Variations of Wastewater Flow
Sou
rce:
AT
V-D
VW
K-A
rbei
tsbl
att A
198
(A
pril
2003
)
Ruralareas
< 5,000 E
Middle towns5,000- 20,000-
20,000 E 100,000 E
Largecities
> 100,000 E
20
Divisor xQmax [ h/d ]
18
12
14
16
10
8
aMInfQ
aMWWhDWhDW Q
x
QQorQ ,
max
,max,2,max,,
24+
⋅=
31
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Dry weather inflow and combined water inflow
Old standard:
New opinion (A-198):
New approach: Seen as an advantage that the mean wastewater flowQWW,aM can present the same initial basis both for the layout of combined sewer overflows and also for the combined wastewater flowto the wastewater treatment plant.
InfWWComb QQQ +⋅= 2
aMInfaMWWQCWWWComb QQfQ ,,, +⋅=
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Dry weather inflow and combined water inflow
Ruralareas
< 5,000 E
Middle towns5,000- 20,000-
20,000 E 100,000 E
Largecities
> 100,000 E
9
6
3
fWW,QCW [ - ] peak factor for the calculation of the wastewater flow
Sou
rce:
AT
V-D
VW
K-S
tand
ard
A 1
98 (
Apr
il 20
03)
aMInfaMWWQCWWWComb QQfQ ,,, +⋅=
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Daily Variations of Wastewater Flow
Qd = 15,000 m3/d
Mean value of 24h
Daytime mean value
Nighttime mean value
Daytime maximum
Nighttimeminimum
Figure: Variations in dry weather flow during the day (Source: ATV Handbook 1, 1994)
Dis
char
ge in
m³/
h
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Design of WWTP1. Determination of inflow parameters
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Design Values Domestic Wastewater Flow
Size of
settlement
Specific do-mestic WW production
Divisor daily peak
Divisor day average
Divisor night average
1000 C wWW,d x x x
- l/(C⋅d) h/d h/d h/d
>250 130-150 16 20 30
50 – 250 120-140 14 18 36
10 – 50 110-130 12 16 48
5 – 10 100-120 10 14 84
< 5 100 8 12 No flow
Example l/(C⋅d) l/(C⋅h) l/(C⋅h) l/(C⋅h)
10 - 50 110 110/12=9,2 110/16=6,9 110/48=2,3
x = Variation factor
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Wastewater from Commerce and Industry
Amount depends onType of commerce/ industry
Production amounts
Production method
Internal circulation
Fluctuations depend onProduction times
Hours/ days
Production cycles (e.g.: Slaughtery periods,..)
Days/ weeks
Seasonal activities
Food industry (e.g. production periods of sugar industry,...)
Tourism
Water saving production methods
Large scale industry mostly direct dischargers
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Wastewater from Commerce and Industry
Reliable values only from investigations
Approximate values from literature
Planning recommendations for new commercial areas or industrial estates (ATV-Arbeitsblatt A118)
Companies with low water demandqi = 0.5 l/(ha⋅s)
Companies with moderate water demandqi = 1.0 l/(ha⋅s)
Companies with high water demandqi = 1.5 l/(ha⋅s)
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Specific Wastewater Production
Commerce Amount Unit
Hospital 0.25 – 0.6 m³/bed
Swimming-pool 0.15 – 0.18 m³/visitor
School 0.02 m³/pupil
Department store 0.1 – 1.0 m³/employee
Restaurant 0.015-0.02 m³/guest
Hotel 0.2 – 0.6 m³/bed
Pulp production 300 m³/t pulp (downward trend)
Paper production 100 15 m³/t paper
Brewery 0.4 – 0.8 m³/hl beer
Dairy 5 m³/m³ milk
Preserves 35 m³/t fruit/vegetable
Textile industry 40 - 120 m³/t product
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Design of WWTP1. Determination of inflow parameters
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Infiltration Water
Origin
Diffuse sources (drainage water)
Rivers
Water drainage on building sites
Leaky sewers (groundwater inflow)
inf (groundwater level)
inf (sewer condition)
Infiltration water is undesirable due to the fact, thatthe pollution of infiltration water is very low, but thetotal water flow is increased, resulting in higherwastewater discharge fees!
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Infiltration Water
Recommendations for Dimensioning
Infiltration water flow
qInf = 0.05 – 0.15 l/(ha⋅s) impervious area
In the separate sewer system for the sanitary sewer
QInf = 100 % QWW
In the combined sewer system (based on average hourly QWW)
QInf = 30 – 40 % QWW
Related to sewer length
qInf = 29 ... (43) ...67 l/(m ⋅ d)
Related to population
wInf = 100 ... (130) ... 150 l/(C*d)
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Infiltration water
Definitions
Infiltration water fraction
Infiltration water addition
Conversion
1
11
+−=
FWZFWA
InfWW
Inf
DW
Inf
Q
Q
Q
InflowWeatherDry
InflowWateronInfiltratiFWAi
+===)(fraction n water nfiltratio
WW
Inf
Q
Q
InflowWastewater
InflowWateronInfiltratiFWZi ==)(addition n water nfiltratio
11
1−
−=
FWAFWZ
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Infiltration water
(Source: DWA Leistungsvergleich 2008)
0
2
4
6
8
10
12
1 2 3
0
50
100
150
200
250
300
350
400
450
500
224
6,3
343
9,9
431
5,0
≤ 25 % 25 – 50% > 50%
Nu
mb
ero
f W
WT
P
Mio
PE
WWTP: 998
Mio P: 21,2
Average value of BW: 42%
Fraction of infiltration water
Infiltration water in BW 2008
Number of WWTP Mio PE
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Infiltration Water
Determination in existing WWTPs:
Minimum inflow during night
Method of yearly wastewater flow
Sliding minimum
Triangle method
Others
Chemical method
Isotope method
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Design of WWTP1. Determination of inflow parameters
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Infiltration Water
Assumption: Variations of infiltration flow result from slow variations of groundwater level, fast variations are the result of surface stormwater runoff
For each day, the dry weather flow is determined as the minimum daily flow out of the 21 preceding days (“digital filter“)
Wastewater flow is determined from drinking water consumption or specific consumption values per inhabitant
Tends to result in higher infiltration flow values than other methods
+ No use of subjective weather code
+ Infiltration flow variation over the year can be shown (seasonal variations)
+ Also suitable for small catchment areas with pumping stations and very large catchmentareas
? Catchment area of WWTP identical with service area of water supply company ?
Use of drinking water for irrigation or industrial uses which do not produce wastewater
Gliding minimum
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Design of WWTP1. Determination of inflow parameters
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Infiltration water
0
5000
10000
15000
20000
25000
30000
35000
40000
1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 1.11 1.12
2001
Inflo
w
[m³/
d]
Wastewater
Infiltration water
Stormwater
FWA = 42,0 %
Gliding minimum
45
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Infiltration water according to the method of the glidingminimum WWTP H. 2006
Hirsau
0
50
100
150
200
250
300
350
400
1 17 33 49 65 81 97 113 129 145 161 177 193 209 225 241 257 273 289 305 321 337 353
QdQT,dQS,dQF,d
TAGE
Ab
fluss
in l/
s
FWA [%]:56,4
2006Berichts-/Veranlagungsjahr
Wat
erflo
win
l/s
Days
QDW,dQWW,dQInf,d
56% of dry weather flow is infiltration water!
46
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Water flows WWTP H. 2006
0
5.000
10.000
15.000
20.000
25.000
30.000
35.000
J F M A M J J A S O N D
Months
Wat
er f
low
in m
3 /d
Qd
QDW
47
Design of WWTP1. Determination of inflow parameters
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Cummulative curves of water flows WWTP H. 2006
0
10
20
30
40
50
60
70
80
90
100
110
0 5.000 10.000 15.000 20.000 25.000 30.000 35.000
Water flow in m3/d
Fre
quen
cy in
%
Qd
QDW
85% value
50% value
QDW,d,85% = 8.727m³/d
48
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Peak flow and combined water flow WWTP H. 2006
QDW,2h,max = 24 · QWW,aM / xQmax + QInf,aM =
24 · 33,9 / 17 + 52,6 = 100,5 l/s
QM = fWW,QCW · QWW,aM + Qf,aM =
6 · 33,9 + 52,6 = 256 l/s
Old standard (ATV-DVWK-A 131 (1991 und 2001)):
Qcomb = 2 · QWW + QInf = 2 · (QDW,2h,max – QInf) + QInf =
2 · (QDW,d,85/f – QInf) + QInf =
2 · (8.727/12 ·24 – 4.544,6) + 4.544,6 =
30.363,4 m3/d = 351 l/s
49
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Determination of loads and concentrations
Determination of inflowing loads for dimensioning the biological
reactor
Determination of cBOD,InB; cCOD,InB; xSS,InB; cTKN,InB,cP,InB,SAlk,InB
Measurements of COD are the most frequently master parameter
COD is the most frequently determined parameter. Values of less
determined parameters could be deflected by ratios between COD and
them (keeping the costs for chemical analysis within limits)
If necessary intensive samplings are needed
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Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Determination of loads and concentrations
Loading cases
Determination on the basis of 2-4-week means
Load at the temperature on which the dimension is based
Load at the lowest temperature
Load at the highest temperature
Special loading cases
Determination of the 85%- Values
Load which is achieved or undercut on 85% of the dry weather days (minimum 40 values)
Building the ratios cCOD,InB/cBOD,InB and cTKN,InB/cCOD,InB for day on which all parameters were sampled
Determination of the relevant loads with these average values
51
Design of WWTP1. Determination of inflow parameters
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Cummulative curve of COD in inflow of biological tank WWTP H. 2006
0
10
20
30
40
50
60
70
80
90
100
110
0 50 100 150 200 250 300 350 400
COD in inflow of biological tank in mg/l
Fre
quen
cy in
%
85% value
50% value
52
Design of WWTP1. Determination of inflow parameters
UNIVERSITÄTSTUTTGART
Cummulative curve of COD load in inflow of biological tank WWTP H. 2006
0
10
20
30
40
50
60
70
80
90
100
110
0 1000 2000 3000 4000 5000 6000 7000 8000
COD load in inflow of biological tank in kg/d
Fre
quen
cy in
%
85% value
50% value
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Design of WWTP1. Determination of inflow parameters
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Example: Yearly temperature curve of wastewater
5
10
15
20
25
1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 1.10 1.11 1.12
was
tew
ater
tem
per
atu
re[°
C]
54
Design of WWTP1. Determination of inflow parameters
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Example: Duration curve of wastewater temperature
5
10
15
20
25
1 51 101 151 201 251 301 351
Was
tew
ater
tem
per
atu
re[°
C]
-cu
mm
ula
tive
-
2000
1999
55
Design of WWTP1. Determination of inflow parameters
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Plausibility check of inflow values
Following ratios could be taken as support for urban wastewateraccording to ATV-Standard A131 (2000) (without relevant impacts of commerce and industry):
COD : Nges : Pges = 120 : 11 : 1,8
Or approximatley
COD : Nges = 1 : 0,08 = ca. 12
Acceptable range
COD : Nges = 6,5 to 16
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Design of WWTP1. Determination of inflow parameters
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Rough estimation values for total nitrogen
Raw inflow: NH4-N x 1,7 = Nges Raw inflow
Example Hof: 16,9 mg/l (mean) x 1,7 = 28,7 mg/l
Inflow biological reactor: NH4-N x 1,2 = Nges inflow biological reactor
Example Hof: 19,9 mg/l (mean) x 1,7 = 23,9 mg/l
NH4-N [mg/l]
TKN [mg/l]
Nges [mg/l]
Norg [mg/l]
Mean 16,9 33,4 35,2 17,5
Minimum 4,4 12,8 14,2 8,4
Infl
ow
WW
TP
Maximum 23,3 46,3 49,9 25,0
Mean 19,9 38,3 39,2 18,5
Minimum 4,7 16,2 17,1 11,5
Infl
ow
b
iolo
gic
al
reac
tor
Maximum 32,4 60,3 60,6 27,9
Nitrogen concentrations in the inflow respectively in the biological reactor of the WWTP Hof
Source: K
A-B
etriebs-Info 2004 (34)
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Design of WWTP1. Determination of inflow parameters
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Example of hydraulics
Maximum, mean and minimum hourly dry weather flows Nov. 01 until Oct. 02
0,00
100,00
200,00
300,00
400,00
500,00
600,00
700,00
800,00
Nov. 01 Dec. 01 Jan. 02 Feb. 02 March. 02 Apr. 02 May. 02 Jun. 02 Jul. 02 Aug. 02 Sep. 02 Oct. 02
Date
Q DW
,hb
zw.
Q DW
,24[l
/s]
QDW,24
QDW,h,min
QDW,h,max
58
Design of WWTP1. Determination of inflow parameters
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Example of hydraulics
Curve of the DW-days about a year from Nov. 2001 until Oct. 2002
0
10000
20000
30000
40000
50000
60000
Nov. 01 Dec. 01 Jan. 02 Feb. 02 March. 02 Apr. 02 May. 02 Jun. 02 Jul. 02 Aug. 02 Sep. 02 Oct. 02
Date
Dai
ly f
low
[m³/
d]
Yearly mean value
9979 m3/d178 DW-days
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Design of WWTP1. Determination of inflow parameters
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Example of the determination of loadsComparison of the daily flows and of the COD loads from Nov. 2001 until
Oct. 2002
0
2000
4000
6000
8000
10000
12000
14000
0 10000 20000 30000 40000 50000
Qd [m3/d]
Bd
,CO
D,I
nB
[kg
/d]
200
350700 500
Parameter CCOD [mg/l]
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Design of WWTP1. Determination of inflow parameters
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Example of the determination of loads
Unterschreitungshäufigkeit der CSB-Frachten Zulauf Bio vom Nov. 2001 bis Okt. 2002
0
10
20
30
40
50
60
70
80
90
100
0 2000 4000 6000 8000 10000 12000 14000
COD [kg/d]
Un
ters
chre
itu
ng
[%
]
85%-Value: 6613,14 kg/d
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Design of WWTP1. Determination of inflow parameters
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Example of the determination of loads
2-weekly mean of the loads of COD in the inflow of biochemical reactor from Nov. 2001 until Oct. 2002
0
1000
2000
3000
4000
5000
6000
7000
8000
16.9 5.11 25.12 13.2 4.4 24.5 13.7 1.9 21.10 10.12
Date
Bd
,CO
D,I
nB
,2w
M[k
g/d
]
Rated value: 7.000 kg/d
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Design of WWTP1. Determination of inflow parameters
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Literature IWastewater Treatment
Degrémont: Water Treatment Handbook Vol. 1 & 2, Lavoisier, Cachan, 2007, ISBN: 978-1-84585-005-0, 978-2-7430-0970-0 Grady, C.P.L., G.T. Daiger, H.C. Lim: Biological Wastewater Treatment, 2. Ed., Marcel Dekker, New York, 1999.Henze, M., Harremoes, P., LaCour Jansen, J., Arvin, E.: Wastewater Treatment, 2. ed., Springer, Berlin, 1997Liptak, B., G., Liu, D.H.F. Environmental Engineers Handbook, 2nd Ed., Lewis Publ., Boca Raton, 1997, Air Pollution, Noise
Pollution, Wastewater Treatment, Removing Specific Water Contaminants, Groundwater and Surface Water Pollution, Solid Waste, Hazardous Waste
Metcalf & Eddy, Inc.: Wastewater Engineering: Treatment, Disposal and Reuse, McGraw Hill, New YorkRich, L. G.: Unit operations of sanitary engineering, John Wiley, New York, 1961Schroeder, E. D.: Water and Wastewater Treatment, McGraw Hill, New York, 1977Stephenson, K., K. Brindle, K., Judd, S., Jefferson, B.: Membrane Bioreactors for Wastewater Treatment. 2000, Portland
Press Ltd. Essex
Water Chemistry
Sawyer, C.N., P.L. McCarty: Chemistry for Sanitary En-gineers, McGraw Hill Book Comp., New YorkStumm, W., Morgan, J.J.: Aquatic Chemistry, Wiley, New York, 4. Ed..
Hydrobiology
Uhlmann, D.: Hydrobiology, a text for engineers and scientists, John Wiley, New York Chichester, 1988
Biotechnology, Modeling, Chemical Engineering
Bailey, J.E., D.F. Ollis: Biochemical Engineering Fundamentals, Mc Graw Hill, Internat. Editions, New York, 1986Blanch, H.W. u. Clark, D.S.: Biochemical Engineering, Marcel Dekker Inc., New York 1997IWA Task Group on Mathematical Modelling for Design and Operation of Biological Wastewater Treatment (Editor): Activated
Sludge Models ASM1, ASM2, ASM2D and ASM3, IWA Publishing, London 2000.Rittmann, B., McCarty, P.: Environmental Biotechnology: Principles and Applications, McGraw-Hill Science/Engineering/Math,
2001Russel, T.W.F., M.M. Denn: Introduction to Chemical Engineering Analyses, J. Wiley & Sons, New York, 1972Snape, J.B., I.J. Dunn, J. Ingham, J.E. Prenosil: Dynamics of Environmental Bioprocesses - Modeling and Simulation, VCH,
Weinheim, 1995
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Design of WWTP1. Determination of inflow parameters
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Literature IIStandards, Advisory leaflets (DIN: Deutsche Industrienorm, EN: European Standard)DIN 4045, 1985-12: Abwassertechnik; Begriffe: Waste Water Engineering; VocabularyDIN EN 1085, 1997-07: Abwasserbehandlung, Begriffe, Terminologie, Wörterbuch: Wastewater treatment – Vocabulary;
Trilingual version EN 1085: 1997DWA: Deutsche Vereinigung für Wasserwirtschaft, Abwasser und Abfall e.V. in English: German Association for Water,
Wastewater and Waste Design Rules in English, Others
GlossariesBains, W.; Biotechnology from A to Z, Oxford University Press, Oxford, 1993
Journals:Environmental Science and TechnologyISSN: 0013-936X, Uni S, Homepage: http://pubs.acs.org/journal/esthagWater ResearchISSN: 0043-1354, Uni S , Homepage: http://www.iwaponline.com/wr/default.htmWater Science and TechnologyISSN: 0273-1223, Uni S: 13.1981 - 50.2004 (LEA).Homepage: http://www.iwaponline.com/wst/default.htmWater Environment ResearchISSN: 1061-4303t: Uni S 64.1992 - 76.2004 (LEA) Homepage: http://www.ingentaconnect.com/content/wef/werWater Practice & TechnologyISSN: 1751-231X, Uni S, Homepage: http://www.iwaponline.com/wpt/Journal of Water Supply: Research and Technology – AquaISSN: 0003-7214 Uni S 1974 – 1979 (LEA), 1959 – 1974 ISWA, Homepage:http://www.iwaponline.com/jws/default.htmWater Resources ResearchISSN: 0043-1397, Uni S: 26.1990 - 40.2004 (LEA), 5.1969 - 33.1997 ISWA, Homepage: http://www.agu.org/journals/wr/Urban Water JournalISSN: 1744-9006, Uni S, Homepage: http://www.informaworld.com/smpp/title~content=t713734575~db=allJournal of Environmental Technology and ManagementISSN: 1741-511X, Homepage: https://www.inderscience.com/browse/index.php?journalID=11