Properties of Reactive Materials for Application in Runoff Water Treatment Systems

The emissions related to urbanized areas, including communication routes and accompanying facilities, are considered as essential sources of subsoil pollution. Enhancement of the naturally occurring removal processes in infiltration systems, e.g. through placing the appropriately selected materials (treatment zones) on the flow path of runoff water, prevents the spread of undesirable components. The article presents the analysis of tests checking the properties of selected low-cost mineral materials, activated carbon and zero-valent iron in terms of their applicability in the runoff water treatment zones. Their physical features, surface structure, and chemical and hydraulic properties were analysed. The test results indicate a well-developed surface area of active carbon and halloysite, as well as an extensive pore volume of active carbon, halloysite, zeolite and diatomite. Nevertheless, the average pore diameters indicated the potential limited access of pollutants to the inner structure of all analyzed materials. The chemical parameters point to the stimulation potential of precipitation processes by limestone sand and silica spongolite, ion exchange by zeolite and silica spongolite, and oxidation-reduction processes by zero-valent iron. The value of the material hydraulic conductivity may potentially limit their application in infiltration systems. Taking into account all analyzed parameters, activated carbon together with silica spongolite and zeolite have the best application potential.