The goal of
this research is to present data for the energy (power) consumption during the
various treatment stages that are taking place in a WWTPs that are processed by
the method Activated Sludge. For that purpose all energy consumption data was
collected on a daily basis in six wastewater treatment plants. This work includes
stage, gathering data from main energy consumption spots in various WWTPs in
different stages of the process.
stage was calculation of energy consumption required to treat one cubic meter
of raw sewage entering the WWTP. This energy consumption is called the
“specific energy consumption”(S.E.C.)
was calculated for different sizes of W.W.T.Ps As classified hereinafter:
Plants - up to 10,000 cm/day, Medium Plants - up to 20,000 cm/day and Big
Plants - over 20,000 cm/day.
conclusions of this research are:
Specific energy consumption per cum of raw sewage
(kWh/cum) in small plants is 2.39 times higher than the S.E.C.in big plants.
Growth in the influent flow under constant
nutrients contribution caused by natural development reduces S.E.C. parameter
of influent entering the W.W.T.
The biological treatment process consumes from
27% to 60% of all the energy demand of the W.W.T.P.
In a WWTP that the sludge treatment is aerobic
the total energy consumption for aeration process only varies from 49% to 53%
of all energy demand in the plant (Such as Bakaa El Garbiee and Yerucham
In WWTP that applies anaerobic sludge treatment
it was found that the total energy demand for aeration only varies from 27% to
39% out of the total energy consumption in the plant (Such as Herzliya and
Kefar Saba-Hod Hasharon WWTPs).
Anaerobic sludge treatment significantly reduces the energy consumption in
comparison with to aerobic sludge treatment (assuming that the final goal in
both is class "B" treatment).
A.T.A.D. sludge treatment (in Kolchey
Hasharon WWTP) demand is some
4.5 Times higher S.E.C than Mesophillic anaerobic treatment (in Beit
WWTP, from same order type and flow) but upgrades sludge treatment from class B
to class A.
the potential methane gas (biogas) production, the total required energy consumed
through the whole process, sewage & sludge treatment, per day is lower than
the energy that can be produced and co-generated.