מגזין המים הישראלי הנדסת מים 32
2017 תקצירי כנס איגוד המים הישראלי
Limiting Nitrite
Oxidation in a
Fixed Bed-Up
flow Nitrification
Reactor
Anwar Dawas | Faculty of Environmental
Engineering, Technion & Research and Development
Center Galilee Society, Shefa; Dr. Samy Abu-
Salih | Mechanical Engineering Dept.ORT Braude
College; Prof. Isam sabbah | Biotechnology
Engineering Dept.ORT Braude College & Research and
Development Center, The Galilee Society; Prof. Ali
Nejidat | Department of Environmental Hydrology
and Microbiology, The Jacob Blaustein Institutes for
Desert Research, Ben-Gurion University of the Negev,
Sde Boker Campus; Prof. Carlos Dosoretz |
Faculty of Environmental Engineering, Technion
Anaerobic ammonium oxidation (ANAMMOX) is widely accepted
as a promising process for nitrogen removal from wastewater with
high ammonium concentration and low C/N ratio. The ANAMMOX
process is more cost effective than a conventional nitrification-
denitrification system due to lower sludge production and saving
over 50% of oxygen with no organic carbon source needed.
In wastewater treatment, ANAMMOX must be combined with a
preceding nitritation stage by ammonia oxidizing bacteria (AOB).
The online control of ammonium oxidation based on dissolved
oxygen (DO), ammonium or conductivity sensors was reported as
a useful method to achieve sustained partial nitrification.
This study explored the stability of partial nitrification in a continuous
fixed bed-up flow biofilm reactor with recycle and external aeration.
The reactor was operated for at least 200 days with limiting DO
concentration, controlled by the recirculation rate. The reactor
was fed with synthetic medium with a 50 mg/L N ammonium
concentration.
Successful control of nitrification was achieved in which 50% of
ammonia was not oxidized, while the remainder was oxidized
and mainly accumulated as nitrite (~45%) with only nitrate 5%
accumulation in the effluent. In addition, a numerical model was
developed using COMSOL as stimulation tool for predicting the
concentration of nitrogen species and oxygen in the liquid and
biofilm phase in the lengthwise of the reactor as function of the
recycling ratio in the fixed bed reactor. In parallel, the dynamic
changes of AOB and NOB associated with the operating conditions
were examined by q-PCR.
Several orders
of magnitude
increase in
hydraulic
permeability of
flow-through
capacitive
deionization
electrodes via
laser perforations
Eric N. Guyes | Faculty of Mechanical
Engineering, Technion IIT; Anastasia
Simanovksi | Faculty of Mechanical Engineering,
Technion IIT; Matthew E. Suss | Faculty of
Mechanical Engineering, Technion IIT
Capacitive deionization (CDI) is a fast-emerging ion removal
technology that shows great promise for applications in water