puhastustehased

Puhastustehased, also known as wastewater treatment plants or sewage treatment works, are facilities designed to remove contaminants from household sewage and industrial wastewater before it is discharged into the environment. The primary goal of these plants is to protect public health and the environment by reducing the amount of pollutants in the water. Treatment processes typically involve several stages, beginning with preliminary treatment to remove large solids like grit and rags. This is followed by primary treatment, where suspended solids settle out of the wastewater in large tanks. Secondary treatment uses biological processes, often involving microorganisms, to break down dissolved organic matter. Tertiary treatment, or advanced treatment, may be employed to remove specific pollutants like nutrients (nitrogen and phosphorus) or pathogens, depending on the required discharge standards. The treated effluent is then disinfected, commonly using chlorine or ultraviolet radiation, before being released into rivers, lakes, or oceans. Sludge, the solid material removed during the treatment process, is also processed further, often through dewatering and digestion, before being disposed of or reused, for example, as fertilizer. The design and operation of puhastustehased are crucial for maintaining water quality and ecological balance.