Short Communication: Potential of Biochar And Clays as Sorbents For Treatment Of Greywater and Related Wastewaters in South Africa

Abstract

Due to the issues of water scarcity, there is a need for formulation of technologies to remove various components wastewaters to produce water that can be reused for irrigation and toilet flushing. Local production of low-cost sorbents and their use in the treatment of greywater were examined in the current study. The aim was to assess whether different clays and/or biochar could be used the potential of the sorbents for greywater remediation. These sorbents were locally mined or sourced/produced in South Africa, and so they could provide a suitable and low-cost treatment option for the greywater treatment and recycling that could allow for water scarcity to be dealt with in South Africa. The sorbents were observed to have average cation exchange capacities of 144.25± 0.22, 147.37± 0.18 (Clay A), and 191.94± 0.40 (Clay B) cmol(+)/kg respectively in methylene blue solution. The same property values were 95.83± 0.14, 96.42± 0.88 (Clay A) and 96.82± 2.20 (Clay B) cmol(+)/kg respectively in brilliant green solution. In the remediation of greywater, biochar had the highest average removal efficiencies of 70.77± 35.77 % for faecal coliforms while clay A and B had 51.11± 8.49 % and 53.86 ±4.42 %, respectively. Performance of the sorbents for removal of electrical conductivity (desalination) from saline water requires further investigation, while in remediation of greywater the sorbents have shown a potential for up-scale greywater treatment via shaking and sedimentation.