Contents
XV
6.1 Immediate Improvement of Water Quality ............................. 267
6.2 Sustainable Restoration by a Dynamic Hydrological Regime 267
7 Summary and Conclusions... .... ......... ...... ...... ..... .... ........ .... ......... ... 269
References... ... .... ..... .......... ........ ... .................... ...... ............ ... .............. 270
Part IV Improving Water Quality
16 Drinking Water Quality for the 21st CenturyNew Technologies for a New Era
H. s. Weinberg.............................................. ................................. 273
1 Introduction.... ...... .... ........ ........ ............ ....... ......... ........ .... ....... ........ 273
2 Regulation ....................................................................................... 274
3 Contaminants in the Treatment Process .......................................... 278
3.1 Treatment Chemicals ............................................................... 278
3.2 Natural Organic Matter (NOM) ............................................... 279
3.3 Algae ......................................................................................... 280
3.4 Bromide ..................................................................................... 280
4 Treatment Technologies .................................................................. 281
4.1 Enhanced Coagulation.............................................................. 281
4.2 Air Stripping............................................................................. 282
4.3 Ozonation .................................................................................. 283
4.4 Granular Activated Carbon (GAC) .......................................... 285
4.5 Biofiltration ............................................................................... 286
4.6 Ultraviolet Irradiation Technology ........................................... 287
4.7 Advanced Oxidation ................................................................. 287
4.8 Semiconductor-Mediated UV Photocatalytic Oxidation (Ti02)289
4.9 Electron Beam ......................................................................... 290
4.10 Alternative Chemical Oxidants............................................... 290
4.11 Mixed Oxidants ....................................................................... 291
4. 12 Membrane Technology ............................................................ 291
5 The Future.. .... .... ........... ........ .... ............. ..... ..... ..... ........ .... ..... ..... .... 294
References........... ............. .... ..... ........... .... ........ ......... ....... ..... ..... ........ 294
17 Turbidity Removal by Polyelectrolytes as
Flocculant Aids in Flocculation with Aluminium Salts
N. Narkis, B. Ghattas, M. Rebhun and A. Rubin. .................... 299
1 Introduction...... ........ ..... ..... ............ .... ........ ..... .............. ... ....... ........ 299
2 Material and Methods ...................................................................... 300
2.1 Aluminium Nitrate.................................................................. 300
2.2 Polymeric Flocculants ....................................... ..................... 300
2.3 Clay Mineral Suspension ......................................................... 300