Investigation of mechanisms of an upflow-downflow siliceous sand filtration system for surfactants bathroom grey water treatment

Abstract

Sustainable Decentralized Wastewater Treatment Systems (DEWATS) at the local level are considered as a smart alternative for small communities particularly in arid areas. The present study examines the mechanisms of an upflow-downflow Siliceous Sand (SS) filtration system involved in surfactants bathroom grey water treatment. In order to get a better understanding of the mechanisms involved in surfactants removal, particle size distribution and Fourier Transform Infrared (FTIR) Spectroscopy of the SS particles were performed. Optimization of the upflow-downflow SS filtration system, operated following operational conditions of Hydraulic Load Rate (HLR) and SS amounts, results indicates an average removal efficiency (ARE) of 93.7% reached with respect to surfactants removal. Results showed also that the resulting silicate materials react with surfactants in a cooperative assembly process involving the interaction of SS particles with surfactants aggregates. Brunauer, Emmett and Teller (BET) surface area, pore volume (Vp), and pore size were found to be significantly reduced post-filtration with respectively 3.39%, 24.31%, and 21.86% reduction. From FTIR spectroscopy analysis of the Sulfonates, Silanol and Silane functional groups appear to be involved in mesoporous constructed micelle organization for surfactants removal. Such geo-materials could be green and sustainable for various applications in water and environmental engineering.