Evaluation of the anti-microbial efficiency of scrap metal-based coagulant and local salt modified-biomaterials for point-of-use water treatment

Abstract

The anti-microbial efficiency of a composite material formulated from a scrap metal-based (iron (III) sulphate) coagulant and indigenous salt (NaCl) activated biomaterials (coconut shell carbon and counter wood) were evaluated by using the composite materials as coagulant and disinfectant adsorbent by treating borehole water and river samples at point-of-use. The results of the microbial analysis of the untreated and treated ABW, FBW, ERWA, and EBRW samples revealed  a 75, 75, 80, and 66.6% bacteria genera removal was obtained during rainy season while there was 100, 66.6, 80, and 100% bacteria genera removal during rainy and dry seasons, respectively. Over 500 isolates of Escherichia coli, Pseudomonas species, Salmonella species and Vibrio cholera; Pseudomonas spp., E. coli, Bacillus species and Salmonella spp.; Shigella species, E. coli, Pseudomonas spp., Salmonella spp. and Staphylococcus species; E. coli, Salmonella spp. and Pseudomonas spp. bacteria genera were identified each in the untreated ABW, FBW, ERWA and EBRW samples during the rainy season, while Bacillus spp. and Citrobacter freundi; Klebsiella pneumoniae, E. coli and Pseudomonas spp.; E. coli, Salmonella spp., Shigella spp., K. pneumonia and Staphylococcus spp.; E. coli and E. faecium bacteria genera were identified during the dry season, respectively. After treatment, 3 and 2 genera of bacteria each were present in 48 and 9 isolates during rainy and dry seasons, respectively. The means of the aerobic bacteria count (ABC) during the two seasons showed no significant variations at p Eƒ 0.05 confidence limit. Key words: Anti-microbial activity, disinfection, coagulant, activated biomaterials.