Copper and Zinc Removal Efficiency of Two Reactive Filter Media Treating Motorway Runoff—Model for Service Life Estimation

Abstract

The predominant techniques used for road runoff treatment are sedimentation and filtration. In filtration systems, the ability of the media to adsorb the contaminants is a finite process. Consequently, construction, operation and maintenance managers of such systems should know in advance the service life, i.e., when the used medium should be replaced, and associated costs of operation and maintenance. A batch experiment followed by a packed bed reactor (PBR) experiment addressed the kinetics of the studied media argon oxygen decarburization slag (AOD) and Polonite, followed by the development of a 1D-model to describe the change of concentration of Cu and Zn within time. The batch test results showed that Cu and Zn adsorption followed the Freundlich isotherms for AOD and Polonite. Those results coupled with the linear driving force model and the developed model resulted in good agreement between the PBR results and the simulation. The model was capable to predict (i), the service life at the hydraulic load of 0.18 m/h for AOD (Cu: 395 d; Zn: 479 d) and Polonite (Cu: 445 d; Zn: 910 d), to show (ii) the profile concentration in the PBR within time and the gradient of the concentration along the height of the reactor.

Evaluation of a sand filter material for road runoff treatment– pilot-scale field trial focused on copper and zinc removal

“…The widely used methods in stormwater treatment is the infiltration basins and wet ponds where sand can be used as an integrated part (Egemose 2018). It is still interesting to assess the use of sand or rock-crushed material as media for treatment of traffic stormwater and we predict an increase of constructions of filter systems with sand alone or, sand filters preceding filtration with so-called reactive (Rodríguez-Gómez et al 2021) or sorptive (Huber et al 2016b) filter media. The sand is expected to reduce the TSS load to the subsequent reactive filter, the life span of which can then be increased because of less clogging and better metal sorption capacity.…”