Lisäpuhdistusmenetelmät

Lisäpuhdistusmenetelmät, often translated as "tertiary treatment" or "advanced wastewater treatment," refer to processes that go beyond conventional primary and secondary wastewater treatment. These methods are employed to remove specific pollutants that remain after standard treatment, aiming for a higher quality effluent, often for reuse or discharge into sensitive environments.

Common lisäpuhdistusmenetelmät include nutrient removal, such as the biological removal of nitrogen and phosphorus. Nitrogen removal typically involves nitrification and denitrification processes, while phosphorus removal can be achieved through biological or chemical precipitation. Another category is the removal of dissolved organic matter and recalcitrant compounds that are not effectively removed by biological secondary treatment. This can involve advanced oxidation processes (AOPs), activated carbon adsorption, or membrane filtration.

Membrane technologies, like microfiltration, ultrafiltration, nanofiltration, and reverse osmosis, are increasingly used as lisäpuhdistusmenetelmät to remove suspended solids, pathogens, dissolved salts, and even specific ions, producing a very high-quality water. Disinfection, often a final step, uses methods like UV irradiation, ozonation, or chlorination to inactivate any remaining microorganisms. The specific choice of lisäpuhdistusmenetelmät depends on the desired effluent quality, the characteristics of the incoming wastewater, and regulatory requirements. These advanced treatments are crucial for protecting water resources and enabling water reuse.