An evaporator is a technology which often allows water to be recycled in closed circuit. Moreover, it is a technique that requires little space and limited manual monitoring.
Water pretreatment is a frequently used technique to purify water. It is actually a collective name for different technologies based on dosing, pH control in function of the residual solubility, sludge discharge...
In case of biological treatment the purpose is usually to reduce the COD, BOD and/or N concentration in the water stream. To this end nitrification and/or denitrification are often the best option.
Nitrogen can occur in water in different forms. Depending on the form and concentration, there is a choice between different techniques to remove nitrogen from water.
In many water treatment processes a sludge fraction is created during the treatment process. This sludge fraction usually needs to be dewatered before being discharged.