Physical wastewater treatment is necessary in all industrial and craftmanship activities who are producing wastewater containing biodegradable surfactants (i.e. car wash plants like tunnels etc.). Physical wastewater treatment is consisting of a combined system between filtration and absorption of the water to be treated. It can also be used in chemical and/or biological treatment units as final treatment. However, mechanical processes like sedimentation and degreasing must come before the physical treatment unit. Mix filters for physical treatment units are consisting of quartz and active coal which are able to filter pollutant substances, respecting contact assets and speed of the water to treat.