® Rainer Abendt Dr.- Ing. Rainer-Werner Abendt Nuremberg Contact: [email protected] Wastewater Workshop in Nairobi 29-th August till 03-rd September 2011 Sewer Systems
Jan 14, 2016
®Rainer Abendt
Dr.- Ing. Rainer-Werner AbendtNuremberg
Contact: [email protected]
Wastewater Workshop in Nairobi 29-th August till 03-rd September 2011
Sewer Systems
®Rainer Abendt
A Recap of the previous module indicated that:-
Sewage purification systems are necessary for health. Because supply of clean water to the population is indispensable for health provision. (National Water Services)
But sewage systems are also important for protection of groundwater or river water.
Why?
Because we need river or ground water to produce drinking water !
Sewer Systems
®Rainer Abendt
Sewer Systems
Sources of raw water in Bavaria
Millions. m³/yr
% value
groundwater from wells 700.7 74,8
groundwater from springs 163.8 17,5
bank filtrate, recharged groundwater 48.3 5,1
surface water 24.2 2,6
Total 937.1 100
®Rainer Abendt
Effluent Standards (emission)
Water Quality Standards (imission)
Education Standards: labours and academic
Health and Safety Standards
2
1
1
2
3
43
4
Sewer Systems
®Rainer Abendt
Treatment plant
Urban area
Evolution of water crowd:
- Sewer construction
Evolution in sewer network:- By-laws
Evolution of Water quality:
- Sewer operation
First step!
Without Stormwater Drainage
-auslässeLegal Orders
Sewer Systems
®Rainer Abendt
Treatment plant
Urban area
Evolution of water crowd:
- Sewer construction
Evolution in sewer network:- By-laws
Evolution of Water quality:
- Sewer operation
Or First step!
With separate Stormwater Drainage
Effluent in a river
-auslässeLegal Orders
-auslässeLegal Orders
Sewer Systems
®Rainer Abendt
Are the stormwater drains connected to the trunk sewer?
If not, where does the stormwater drain to?
Urban area
Evolution of water crowd:
- Sewer construction
Evolution in sewer network:- By-laws
Evolution of Water quality:
- Sewer operation
Storm- and Wastwater mixed
Stormwater Effluents
Treatment plant
-auslässeLegal Orders
-auslässeLegal Orders
Or First step!
Sewer Systems
®Rainer Abendt
Wastewater disposal(Discharge and treatment)
Administration:
Finances;
Personnel
By-laws:
Connection approval;Industrial monitoring;Cost covering
Sewer construction:
General drainage;Sewer network expansion;Sewer operation:
Maintenance, repair, operation/control of storage space and outlets (provisions under water law)
Sewer Systems
®Rainer Abendt
Sewer Systems
• Pipe Varieties in Nuremberg, Germany.
These are examples of types of pipes needed for various transmission works
In selecting a pipe material for sewer service, the design engineer must evaluate standards for materials, products and systems
The standards must meet international specifications and must have passed Proficiency Testing Programs for quality assurance.
®Rainer Abendt
Technical Standards of Materials
Product &Testing Standards guarantee quality.Check the:-pipe diameterPipe MaterialPipe thickness
Sewer Systems
®Rainer Abendt
First WASPA Annual International Conference 8-9th September 2011, KICC Grounds, Nairobi, Kenya
DEN = Technical European Norms
Free trade
®Rainer Abendt
Examples of Standards Quality of on Water Materials:
CEN TC 155 „Plastics piping systems“ “
CEN TC 163 „Sanitary appliances “
CEN TC 164 „Water supply “
CEN TC 165 „Waste Water Engineering“
CEN TC 203 „Cast iron pipes “
CEN TC 208 „Elastomeric seals“
CEN TC 230 „Water analysis “
CEN TC 308 „Characterization of sludges“
Sewer Systems
®Rainer Abendt
Example: ‘Visual inspection coding system,
Sewer Systems
®Rainer Abendt
Wastewater types (QWW):1. Domestic wastewater (QD) such as: shower water
swimming pool water flushing water
faecal water2. Commercial and/or industrial wastewater (QInd)
such as: production water treatment water cooling water
3. Infiltration water (QIW)4. Stormwater (rainfall) (QR)5. Melt water
Daily amount of wastewater, normal in Europe:average: 125 - 200 l / (per individuaI per day)frequently: > 300 l / (per individual per day) due to increased amounts of
infiltration water (QIW)
Sewer Systems
®Rainer Abendt
Parameters in Wastewater pollution (raw sewage):
Inhabitant-related loads in raw wastewaterBOD5 : 60 g/(per Individual per day)COD: 120 g/(per Individual per day)filterable solids: 70 g/(per individual per day)Ptot: 1.8 g/(per individual per day)Ntot: 11 g/(per individual per day)Ntot in raw wastewater mainly as TKNTKN (Total Kjeldahl Nitrogen): Norg + (NH4
+ - N)undissolved matter: 30 %dissolved matter: 70 %
Sewer Systems
®Rainer Abendt
Sewer Systems
Wastewater pollution (raw sewage):
Concentrations of minimum parameters in domestic raw wastewater:
BOD5: 200 - 400 mg/l
COD: 400 - 800 mg/lPtot: 5 - 12 mg/l
Ntot: 30 - 75 mg/l
®Rainer Abendt
The wastewater discharged into the sewer system should not possess the following characteristics:
1. Free acids (pH values < 6.5) and strong lyes (pH > 8.5)2. Salts in high concentrations3. Strong poisons (toxic substances, e.g. Cu ions)4. Oils and greases (mineral oils)5. Hazardous and explosive gases (e.g. methane, petrol
fumes)6. Odorous substances (e.g. sulphides from leather
processing)7. Large quantities of suspended or heavy settleable solids8. Radioactive substances (e.g. from hospitals)9. High Temperatures (over 35 °C)10. Heavy discoloration (e.g. from the textile processing
industry)
Sewer Systems
®Rainer Abendt
Sewer Systems
t [h]
Q [l/s]%
200
150
100
50
0
190
180
170
160
140
130
120
110
90
80
70
60
40
30
20
10
5.00 5.009.00 13.00 17.00 21.00 1.00
Reserve für Regenwasser, Q
SchmutzwasserQ
FremdwasserQ
QKW
RW
FW
SW
The daily variation of waste water %
Wastewater
Infiltration Water
Pipe capacity for stormwater
®Rainer Abendt
Sewer Systems
Cost Reduction:
You can reduce your treatment costs, if you ensure non-soiled wastewater does reach the sewer network at all.
In a mixed sewer net (rain and wastewater) you can reduce your costs by building a storm water tank at a quarter the distance from the start of the trunk sewer with a drain time of 10 to 15 minutes in the channel.
®Rainer Abendt
Sewer network of NurembergTreatment plants
Sewer network
Stormwater tank
Sewer Systems
®Rainer Abendt
Sewer Systems
Schematic profile
®Rainer Abendt
Sewer Systems
Diagram
®Rainer Abendt
Water quality of the river
Sewer Systems
®Rainer Abendt
Demands on water quality (Europe):Demands on water quality (Europe):
COD
BOD5
Ammonia Ntot
PtotSuspended Solid
Why Sewage Purification ?
®Rainer Abendt
Laboratory
operating data
Demands on the sludge
Legal orders
Secure disposal
Government control
Automatic monitoring
Legal orders
Treatmentplant
(Process system)
Product 2 "Sludge"
Product 1 „Clean Water"Urban area
Evolution of water crowd:
- Sewer construction
Evolution in sewer network:- By-laws
Evolution of Water quality:
- Sewer operation
Administration
Personnel
Documentation
Financialmanagement
Sewer Systems
?
®Rainer Abendt
How then does a
Treatment Plant look like ?
Sewer Systems