Due to the reduction of water resources and environmental issues as well as economic savings, water recycling in residential complexes (dormitories, barracks and educational complexes) and recreational complexes (swimming pools, hotels, tourist complexes and tourism) is very important.

 The gray effluent of car washes and car washes, due to their chemical polluting nature, poses a serious risk to the environment. Therefore, the removal of pollutants and water recycling in these industries is very important from an environmental and economic point of view.