Physicochemical Characterization of Natural Rocks and Their Applications for Wastewater Treatment

Arid countries such as Arabian Gulf countries are suffering from a water shortage, especially with the recent high-water demand. The best solution for this shortage is the management of currently available water resources, through the reuse of treated wastewater for irrigation purposes. This solution also solves the problem of regularization of wastewater discharge, with positive impacts on the environment. This study aimed to apply an innovative, advanced method for treating wastewater with a favorable environment, low economic cost, and less energy consumption. The research investigated the possibility of using natural rocks such as volcanic and zeolite for advanced treatment of wastewater effluent. The research methodology relied on an experimental work in the lab scales and applied on materials available in Saudi Arabia. The experiments included a leaching batch test to first examine what leaches out from these rocks into water. Then, the materials were tested with wastewater effluent. The main mechanism of treatment was based on the absorption process. The results exhibited significant improvement in the water quality of treated wastewater. On the other hand, the results of the leaching tests showed many ions being dissolved from both rocks into water; thus, it is recommended to soak and flush these solid materials with clean water before using them for the treatment process. Further research is required to determine the best pretreated methods to be applied on these rocks to improve their performance as absorbents.