How to treat domestic wastewater?

WHAT IS DOMESTIC WASTEWATER? 

There are different types of wastewater linked to human activity in France: we can mention mainly industrial water and domestic wastewater. Domestic wastewater is made up of tap water, water used for toilets, and gray water, or domestic water, which comes from showers, discharges from household appliances (washing machine, dishwasher). 

An inhabitant rejects on average 200 liters of water with more or less pollution per day, we speak of inhabitant equivalent. These waters mainly contain organic and nitrogenous matter and some household chemicals such as detergents.

HOW TO TREAT DOMESTIC WASTEWATER?

For collective treatment, wastewater is transported to a treatment station through a sewerage network. The establishment of a traditional sector that makes up a water treatment plant is a succession of systems, designed to extract the various pollutants contained in the water in different stages.  Biological treatment is often the heart of the treatment system. 

This solution ensures the elimination of pollutants, in particular part of the pollution, thanks to microorganisms.A treatment plant will generate a discharge of clean water and sludge. Most of the sludge is produced in two stages. 

The primary sludge is collected during the settling of the suspended matter contained in the water arriving at the treatment station. 

Secondary sludge is generated by the production of microorganisms during the biological treatment step. The purpose of all the treatments is to treat the water sufficiently so that it does not alter the quality of the natural environment in which it is discharged. Thus, the discharges will have no impact on public health.