Use of Moringa spp. seeds for coagulation: a review of a sustainable option

Regrettably, it is still common to find places without access to safe drinking water due to a lack of resources or appropriate technologies to support adequate solutions. Remedial efforts will need to focus on appropriate solutions for such locations. Coagulation with Moringa spp. seeds has been proposed as a sustainable option for water treatment for low-income locations due to the many other uses of the Moringa tree. Yet, its application is not limited to particle separation. A survey of the databases of WOK (Web of Knowledge) and CSA (Cambridge Scientific Abstracts) identified studies utilising Moringa spp. seeds as a coagulant. Although the majority of the studies were of laboratory or household applications, there were also reported trials in pilot- and full-scale treatment trains. Moringa spp. seed extracts were assessed as primary coagulants, co-coagulants (with aluminium sulfate) or secondary coagulant aids (flocculants). Turbidity reduction efficiencies vary according to the source water characteristics, coagulant preparation technique, and seed type. Treatment benefits of coagulation with Moringa spp. seeds are objectively assessed and have been contrasted with practical considerations in view of its sustainable application.