Water retention and evaporation in a coulumn of sand mixed with water-absorbing polymers

Abstract

To test the effect of water-absorbing polymers to water retentions in sand columns and measure the diffusion coefficient for a number experimental conditions. Water-absorbing polymers increase water holding capacities in sand columns and can increase water retention in sand column compared to WAP-free sand and sand mixed with WAP under the same ambient air conditions. After 12 hours of experiments, water contents of sand columns containing WAP were found to be higher than those of WAP-free sand columns. The diffusion coefficient used in the diffusion model is itself a function of water content. For theses experiments the most appropriate diffusion coefficient found to be most appropriate ins in the linear form : Dᵣ = am + (1-a) Where a = 0.30.