Waste Water Treatment
Goal: To remove materials such as suspended matter, micro organisms and recycle water.
Primary Treatment: Removes 60% of the solid materials and 1/3 of the oxygen demanding waste. It passes through a mechanical filter to remove large objects, then through a grit chamber in order to remove sand and small objects. At last, it passes through as a sendimentation tank where it undergoes a mix of calcium hydroxide and aluminium sulfate, allowing alumiun hydroxide to precipitate carrying dirt particles.
Secondary Treatment: removes 90% of the oxygen demanding waste, such as bacterias. It degrades the waste aerobically using oxygen and bacterias. The organic matter is degraded by bacterias, thus passing through a bed of rocks. The waste produced contains organic waste that is recycled.
Tertiary Treatment: Removes metal ions, phosphates and nitrates. Metal ions and nitrates are removed through precipitation,. For the precipitation, it is used alumiunium sulfate or calcium oxide. However, nitrates are difficult to remove. Anaerobic denitrifying bacteria reduces it to nitrogen or the water can go through an algae pond where the nitrate is used as a nutrient.
Primary Treatment: Removes 60% of the solid materials and 1/3 of the oxygen demanding waste. It passes through a mechanical filter to remove large objects, then through a grit chamber in order to remove sand and small objects. At last, it passes through as a sendimentation tank where it undergoes a mix of calcium hydroxide and aluminium sulfate, allowing alumiun hydroxide to precipitate carrying dirt particles.
Secondary Treatment: removes 90% of the oxygen demanding waste, such as bacterias. It degrades the waste aerobically using oxygen and bacterias. The organic matter is degraded by bacterias, thus passing through a bed of rocks. The waste produced contains organic waste that is recycled.
Tertiary Treatment: Removes metal ions, phosphates and nitrates. Metal ions and nitrates are removed through precipitation,. For the precipitation, it is used alumiunium sulfate or calcium oxide. However, nitrates are difficult to remove. Anaerobic denitrifying bacteria reduces it to nitrogen or the water can go through an algae pond where the nitrate is used as a nutrient.
