Joint International Conference on Long-term Experiments ...

As a result of the comparisons between the aerobe and anaerobe processes the
advantages of introducing the anaerobe processes for the treatment of wastewater with
medium and high charges were discovered.( Minovsky J.,2002).
CASE STUDY
Brewery’s purification plant was initially designed for the purification of wastewater
using the aerobe biological purification process, but because the results were not
satisfactory, they decided to upgrade it and to introduce an anaerobe pre-purification
phase achieved in a reactor UASB type and then the aerobe treatment of the effluent
corresponding to this phase.
THE DESCRIPTION OF THE TECHNOLOGICAL PROCESS
In table 2 the main characteristics of the process are introduced:
Table 2: Parameters specific to purification process
Parameters Unit of measurement Values
COD mg/l 10500
DEBIT mg/l 4200
COD mg/l 2181
TSS mg/l 750
Temperature
o
C 30
pH - 5-8
The wastewater from the brewery with an 86 m 3 /h output will be pumped to a buffer
tank with a 780 m 3 volume, only after a separation of the solid substances of higher
volume in a static filter, the suspended solids being collected in a container for wastes.
The water is passed from the buffer tank where it is constantly mixed with the help of
two submersible mixers. The period of water retention in the buffer tank is 13 h.
After the evaluation of the costs and for their reduction, it was concluded that the
integration of a neutralization tank inside the buffer tank was a good solution.
The chemical dosage and the recirculation of the anaerobe effluent will be done in
this neutralization tank. The measuring of the pH in this tank is continuous. From the
correction tank the water is pumped for the anaerobe treatment with the help of two
pumps. The influent flow is constantly maintained with the help of an electromagnetic
flow measuring device. The output of the influent is 111 m 3 /h.
The reactors active volume is estimated at about 370 m 3 /reactor, so there is a total
active volume of 740 m 3 . This volume releases a volumetric COD charging of 6,1
kg/m 3 . In the anaerobe reactors a 80 –85% purification productivity should be achieved,
the methane production is 0,3 m 3 CH4/COD removed for a concentration of 80% CH4
out of the biogas production.
The characteristics of the anaerobe effluent are:
- COD: 436 mg/l
- BOD: 260 mg/l
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