Specialized and Advanced Water Treatment Processes

This chapter describes specialized treatment processes used to address specific contaminants potentially present in raw waters. Process options are given for water softening and complete demineralization, the removal of iron, manganese, aluminium, arsenic, chromium, radionuclides, nitrates and ammonia and of natural organic matter and micropollutants and treatment to add or remove fluoride and to minimize lead pick-up in distribution. Aeration applications are described for the removal of carbon dioxide, tastes and odours and volatile organic compounds. Advanced treatment processes are described including granular activated carbon adsorbers, biological activated carbon reactors, ion exchange advanced oxidation as well as methods of desalination including electrodialysis, reverse osmosis, nanofiltration and thermal processes and remineralization post-desalination. Separate sections discuss corrosion causes and prevention, the costs of desalination and effluent disposal.