Drinking Water Treatment, Organic and Mineral Micropollutants

Chapter 10 Removal of Micropollutants 1 10.1 Introduction 1 10.2 Pesticides 2 10.3 Pharmaceuticals and industrial waste 4 10.4 Pesticide removal technologies and emerging MPs 12 10.4.1 Adsorption onto activated carbon (AC) 13 10.4.2 Ozonation 51 10.4.3 Ozone-activated carbon combination 66 10.4.4 Advanced chemical oxidation 71 10.4.5 Nanofiltration and reverse osmosis membranes 80 10.5 Frogbox ® : an effective monitoring and control tool 95 10.6 The evolution of micropollutants in drinking water plants 97 10.7 References 99 Chapter 11 Removal of Perfluorinated Compounds 105 11.1 Physicochemical properties 106 11.2 Presence in the water 108 11.3 Drinking water regulations 108 11.4 Treatments 108 11.4.1 Coagulation–flocculation–settling (or flotation) 108 11.4.2 Chemical oxidation 109 11.4.3 UV oxidation 109 11.4.4 Activated carbon 109 11.4.5. High-pressure membranes: nanofiltration and reverse osmosis .. 115 11.5 Conclusion 120 11.6 References 121 Chapter 12 Biological Removal of Ammonia 125 12.1 The principle of biological nitrification 125 12.2 Design parameters 127 12.2.1 Dissolved oxygen 127 12.2.2 Filtration rate 129 12.2.3. NH + 4 concentration removed as a function of temperature (°C). 129 12.2.4 Applicable volume load 129 12.2.5 Contact time 131 12.2.6 Material height 131 12.3 Factors limiting oxygen 131 12.3.1 Mineral carbon 131 12.3.2 pH 132 12.3.3 Temperature 132 12.3.4 Other elements 133 12.3.5 Biological filter washing 133 12.4 Implementation 134 12.4.1 Sand filtration 134 12.5 Biofilters (Biocarbon ® process) 137 12.6 Water treatment stations 140 12.6.1 Treatment stations with conventional sand, dual media or GAC filtration 140 12.6.2 Treatment stations with Biocarbon ® filters 143 12.7 References 146 Chapter 13 Nitrate Removal 149 13.1 Biological treatment 150 13.1.1 Biochemical reactions 151 13.1.2 Nitrite formation 153 13.1.3 The bacteriological aspect 154 13.1.4 Biofilter description (Biodenit ® process) 154 13.1.5 Water treatment stations including biological denitrification 159 13.1.6 Factors affecting biological denitrification 163 13.1.7 Design parameters: applied volumic load 166 13.1.8 Design parameters: minimum contact time (tc min) 167 13.1.9 Design parameters: height of Biodagen ® material (m) 167 13.1.10 Design parameters: material volume (m 3) 168 13.1.11 Partial treatment 168 13.1.12 Sludge production 170 13.1.13 The reagents 170 13.1.14 Biological denitrification implementation and exploitation 174 13.2 Treatment with ion exchange resins 175 13.2.1 General exchange mechanism (Ecodenit ® process) 176 13.2.2 Ecodenit ® process technology 180 13.2.3 Integration into the water treatment station 187 13.2.4 Packaged solutions 188 13.3 Nitrate removal by high pressure membranes 188 13.4 References 194 Chapter 14 Removal of Perchlorates 199 14.1 General aspects 200 14.2 Main processes for removing perchlorate ions 200 14.2.1 Ion exchange resins 201 14.2.2 Nanofiltration membranes 208 14.3 Conclusions regarding the removal of perchlorates 211 14.4 References 212 Chapter 15 Water Softening 215 15.1 Water hardness 215 15.2 Alkalinity 216 15.3 Langelier index (LI or LSI) 220 15.4 Drinking water hardness goals 220 15.5 General principles of water softening 221 15.5.1 The main chemical reactions with lime and soda 224 15.6 Water softening chemical processes 233 15.6.1 Limitations of the process and empirical considerations 234 15.7 Veolia water softening technologies 235 15.7.1 Clariflocculator 235 15.7.2 Actiflo ® softening 238 15.7.3 Multiflo ® softening 243 15.7.4 Catalytic water softening 248 15.8 Saphira ® process 283 15.9 Water softening using high-pressure membranes 286 15.10 Water softening using ion exchange resins 286 15.10.1 Resin resistance: use precautions 287 15.10.2 Ca 2+ and Mg 2+ removal 288 15.10.3 Bicarbonate removal 289 15.10.4 Resin operating capacity 290 15.10.5 Operating parameters 290 15.11. Comparison between the four water softening solutions discussed 292 15.11.1 Advantages and limitations of the different solutions 292 15.12 References 293 Chapter 16 Metal Removal 297 16.1 Iron and manganese removal: general aspects 297 16.1.1 Presence of iron and manganese at the resource level 297 16.1.2 Presence of iron and manganese at the production level 299 16.1.3 Regulatory aspects of iron and manganese 301 16.1.4 Iron and manganese treatments 302 16.2 Arsenic removal 356 16.2.1 Arsenic chemistry 357 16.2.2 Arsenic treatments 360 16.3 Removal of selenium (Se) 391 16.3.1 The chemistry of selenium 392 16.3.2 Selenium removal treatments 394 16.4 Nickel removal 402 16.4.1 The chemistry of nickel 402 16.4.2 Nickel removal treatment 403 16.5 References 412 Index 423 Summaries of other volumes 425