Evaluating the degree of chemical contamination of underground aquifers in Botswana and analysing viable purification and desalination means; a review

• Published in: Chemical engineering research & design 2022-06, Vol.182, p.216-224
• Main Authors: Kandjou, Vepika, Nkwe, David O., Ntuli, Freeman, Keroletswe, Ngonye
• Format: Article
• Language: English
• Subjects: Aquifers; Arid regions; Botswana; Contaminants; Desalination; Groundwater pollution; Leaching; Nanofiltration; Salinity; Water purification; Waterborne diseases
• ISSN: 0263-8762; 1744-3563
• DOI: 10.1016/j.cherd.2022.03.055

Underground water reserves are crucial water sources for sustaining various ecosystems in semi-arid countries like Botswana. These waters are however compromised in quality from the leaching of various salts/minerals into the aquifers as well as rock weathering. It is therefore of high importance to sum the quality of underground waters in various sections of the country. The presence of fundamental contaminants like mono/divalent salts in different regions of Botswana is outlined in this review and henceforth give an understanding on the overall quality of the waters in the country. The review aims to bring a general awareness on the quality of underground waters in Botswana and the region at large. A discussion of current small scale and large-scale purification means deployed is also entailed, to give a foundation for future research and innovation in these areas. Furthermore, newer possible ways in which chemically tainted underground waters can be purified effectively, both industrially and using portable homemade nanofiltration lab-scale setups are described. The fundamental aim of this review is to lay a foundation for policy making in terms of suggesting various purification means with respect to each region in the country in the government’s attempt to reduce waterborne diseases and improve the inhabitants’ life quality. [Display omitted] •An evaluation of chemical contamination of aquifers in Botswana.•Data of the regional contamination of underground waters throughout Botswana is given.•Possible purification means are discussed in details.•The use of graphene oxide and its efficiency in water purification is discussed.