Dow Water Solutions has created a model that determines the lifetime of adsorptive arsenic removal media based on the chemistry of the water being treated. Results of the semi-empirical study will be presented at the 2007 National Ground Water Association's "Naturally Occurring Contaminants Conference: Arsenic, Radium, Radon, Uranium," held in Charleston, S.C. March 22 to 23. The study, authored by Fredrick W. Vance, development specialist, and Geofrey P. Onifer, new business development project manager of Dow Water Solutions, predicts the impact of water quality on the performance of adsorptive arsenic removal media and also highlights the importance of media selection and performance to the overall water treatment system design.
Dow created a model that projects the impact of silica and pH levels of the water, in addition to the level of arsenic contamination, on its proprietary ADSORBSIA titanium-based arsenic removal media. The results indicate that silica and pH, as well as other competing ions present in the water, can affect the capacity and bed performance of adsorptive media as much as arsenic levels. The ability to predict the performance of the media based on these influential factors is a critical step in determining the optimum design, size, and configuration of an arsenic removal system.
Arsenic occurs most predominantly in groundwater and is formed by the dissolution of minerals as rocks and soils erode.
Source: Dow Water Solutions
