Professor
Residency: Israel
- 1979
- Technion - Israel Institute of Technology;
- Civil Engineering
- 1982
- Technion - Israel Institute of Technology;
- Environmental Engineering
- Title of Thesis:
- "Grit chamber operation using circulation
- by water jets"
- Prof. M. Diskin).
- D.Sc.
- 1986
- Technion - Israel Institute of Technology;
- Environmental Engineering
- "Nitrogen removal in a single- sludge
- activated-sludge system"
- Prof. Y. Argaman).
- Water and wastewater treatment
- Biological wastewater treatment
- Modeling of treatment processes
- Detoxification of industrial and hazardous wastes
- Remediation of contaminated soils and groundwater
- Application of microfiltration and deep-bed sand filtration for secondary effluents
- Biofilters for stormwater harvesting and groundwater remediation
- Removal of antibiotics by biological treatment and membrane processes;
- Population dynamics in a bioreactor treating complex chemical wastes;
- Biodegradation of brominated flame retardants.
- Development of a hybrid bio-filter for storm-water harvesting and groundwater remediation
- Removal of antibiotics by biological treatment and membrane processes. MBR effluent quality was compared with those of CAS systems followed by ultrafiltration (UF) operated and tested in parallel, and removal mechanisms were studied. A set of organic micro-pollutants was investigated, including antibiotics such as roxythromycin (ROX), claritromycin (CLA), erythromycin (ERY), trimetroprim (TMP), sulfonmetoxazole (SMX), and sulfometazine (SMZ). Other compounds such as benzotrialzole (BT), 5-tolyltriazole (5-TT), 4-tolytriazole and bisphenol A were also determined. Analysis was conducted by solid phase extraction followed by liquid chromatography and mass spectrometer. Population dynamics in a bioreactor treating complex chemical wastes This study is dedicated to the study of microbial processes and population dynamics in the biological treatment of complex and toxic chemical wastes. One of the interesting phenomena encountered during this study was the relatively drastic effect of small changes in temperature in the range of 38 to 42 o degrees centigrade on bacterial diversity and stability. Other findings indicate a correlation between changes in host abundance and changes in the concentrations of specific phage predatory to these hosts, consistent with the ‘phage kill the winner’ hypothesis. Biodegradation of brominated flame retardants Dibromoneopentyl glycol (DBNPG) and Tribromoneopentyl Alcohol (TBNPA) are brominated flame retardants commonly used as additives during the manufacture of plastic polymers and as chemical intermediates for synthesis of other flame retardants. Both are classified as not readily biodegradable. Their biodegradation by a common bacterial consortium under aerobic conditions in enrichment cultures containing yeast extract was demonstrated. It was accompanied by the release of bromide into the medium, due to a biological debromination reaction.
- Development of a hybrid bio-filter for storm-water harvesting and groundwater remediation. Water Sensitive Cities is an innovative concept incorporating among others, harvesting, treatment, and reuse of storm-water. This approach is much more sustainable in regard to energy consumption and to the effect on micro-climatic conditions, and has a potential to recover significant amounts of water that are lost in the sea. Moreover, it incorporates added values such as: prevention of soil and structures degradation, reduction of nutrients loads on receiving streams, and creation of aesthetic green landscapes. Use of engineered bio-filtration systems for harvesting and treatment of storm-water has been tested and applied in various countries such as Australia. However the application of this attitude in Israel is much more complicated due to the prolonged dry climate period in Israel (with no drop of rain) during 7-8 months of the year. If a biological filter concept is to be applied to remove predominantly nitrogen compounds (by plant assimilation and by bacterial nitrification and denitrification), continuous wetting of the system should be done to enable biomass (both plant and bacteria) survival. Therefore, a modified version of the bio-filter (originally planned for continuous harvesting and treatment of low level concentrations of nutrients during the whole year – as practiced in Australia) should be used. The approach suggested herein is to use the same system for both storm-water harvesting/polishing (during winter) and for groundwater remediation, mainly, reduction of high nitrate levels typical to many locations in the coastal aquifer of Israel (during summer). The results presented herein contain summary of laboratory column study and of a full-scale field study. The aims of the laboratory research was to find an efficient solid carbon source for the denitrification process, which allows a sufficient nitrate removal and emits very low concentrations of undesired substances such as nitrite and soluble organic materials. Several liquid and solid carbon sources (including wood chips, straw, cotton wool, potato starch, methanol, and glucose) were tested. It was found that solid carbon sources such as crude cotton, wood chips, or straw could serve as effective carbon sources, since the soluble organic substrate for denitrification is derived from their slow hydrolysis. In the second stage of this research study, engineered bio-filters were designed and operated for the treatment of synthetic mixtures simulating nitrate-contaminated groundwater. The columns were filled with graded soil layers mixed with alternative solid carbon sources. The performance of the bio-filters was judged by analyses of nitrate, nitrite, TOC, ammonia, sulfate, and dissolved oxygen concentrations along the columns. Other parameters were assessed too, including pH, turbidity, temperature, hydraulic load, porosity, and head loss gradient. It was found that such bio-filters could remove nitrate to the desired concentration value of <50 mg/L, while at the same time very low concentrations of TOC and nitrite were emitted.
Publications and funding summary / representative publications and grants