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Magdeburg Refuge

Site description and boundary conditions
Design and treatment efficiency

Site description and boundary conditions


boundary conditions
maximum daily organic load [PE]
 98
maximum hydraulic load [m3/d]
 3
annual organic load [kg BOD/a]
 123
altitude [m a.s.l.]
 1633
sensitivity [hydrogeology, protected area ...] nature reserve, limestone
lagal requirements [BOD elimination]
 80%
operation period [season]
 summer
energy supply [type, kW]
 photovoltaic, 0.4
aggregate, 3
means of transport [type]
 lorry
existing WWTP [type, condition, volume l/PE]
 3-chambers, good condition, 156
 
 
Abb. 4.32
Fig. 4.32:   Two stage biological treatment system including a pond and a vertical flow soil filter


Abb. 4.33
Fig. 4.33: Location and lay-out of the WWTP Magdeburg Refuge adapted to the terrain of the site (manholes of the septic tanks above the pond).


Design and treatment efficiency

Loading pond

WWTP Magdeburg Refuge
seasonal average
max. week
max. day
loading [EW40]
13
53
98
BOD5-load [kg/d]
0.53
2.1
3.9
influent flow Q [m3/d]
0.5
1.1
3.0

 

Design of the pond (1. stage) according to the specific load and the retention time

(1) Specific load (seasonal average): BR  ≤ 0,015 kgBOD5/m³ . d,  V > 35 m³

(2)  Specific load (max. day): BR < 0,15 kgBOD5/m³ . d, V > 26 m³

(3) Retention time (seasonal average): tR³ 10 d, V > 5 m³

 
Required volume V = 35 m³
(available area A = 70 m², average depth h = 0,5 m)


Loading soil filter

WWTP Magdeburg Refuge
seasonal average
max. week
max. day
BOD5-elimination [%]
70
65
60
BOD5-load [kg/d]
0.16
0.74
1.56

 

Design soil filter (2. stage) according to specific load


(1)  Specific load (seasonal average): B R ≤  0,005 kgBOD5/m³ . d,  V > 32 m³

(2)  Specific load (max. day): BR < 0,05 kgBOD5/m³ . d, V > 31 m³

 
Required area A = 40 m²
(average depht h = 0,8 m according ÖNORM)

 

Energy demand

max. power
[W]
max. electric work
[kWh/d]
mean electric work
[kWh/d]
200
0.2
0.1 (Qrezirkulation =0,9m3/d)

 

Treatment efficiency

date
[dd.mm.yyyy]
COD effluent [mg/l]
NH 4-Neffluent [mg/l]
NO 3-Neffluent [mg/l]
COD elimination [%]
N elimination [%]
loading
[% of PW max ]
24.08.2000
75 (310*)
20 (62*)
23 (0,8*)
92
54
22
09.07.2001
35 (220*)
15 (56*)
78 (0,5*)
97
29
10

* Concentrations in the pond


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28. Mar 2002