Optimization of Coagulation-Flocculation Process for the Treatment of Wastewater Using Inorganic and Three Natural Coagulants

Authors

  • A. S. Adewuyi Department of Civil Engineering; Federal University of Technology, Akure, Nigeria
  • J. R. Adewumi Department of Civil Engineering; Federal University of Technology, Akure, Nigeria

Keywords:

Organic Coagulants, Inorganic Coagulants, Wastewater treatment, Floc formation Supernatant

Abstract

This paper presents the coagulant activity of three organic coagulants namely; Abelmoschus esculentus (okra mucilage), Bridelia ferruginea (tree bark extract) and Ficus exasperata (sand-paper ï¬g-tree) bark extract was investigated and their efficiency in treating both industrial and domestic wastewater was compared to inorganic chemical coagulant (Aluminum sulphate). The tests were conducted using the jar test apparatus where 250 ml of wastewater was initially coagulated with 100 ml of Al2(SO4)3 as control. Thereafter, varying percentages of the three organic coagulants were used as partial replacement for Al2(SO4)3 in the mixture at intervals of 10% (from 0% -100%). For the cassava wastewater (industrial) with an initial turbidity of 168 NTU, results show that the lowest turbidity attained upon application of the three organic coagulants was 6 NTU at a pH of 2.50. This was achieved when 40% of Bridelia ferrugineae extract was used as partial replacement for Al2(SO4)3. For the domestic wastewater with an initial turbidity of 125 NTU, results show that the lowest turbidity attained upon application of the three organic coagulants was 8 NTU at a pH of 3.04. This was achieved when 90% of Bridelia ferrugineae extract was used as partial replacement for Al2(SO4)3. The results have shown that the organic coagulants employed in this study can be used as partial replacement for inorganic coagulant. This will help mitigate the negative effects associated with the use of inorganic coagulant in the treatment of wastewater.

References

Adewumi, J. R. (2014). “Water Resources Engineering” Lecture note of Water Resources Engineering for PGD Class – CVE 728, Department of Civil and Environmental Engineering, Federal University of Technology, Akure.

Ajibade, F. O. and Adewumi, J. R. (2017). Performance Evaluation of Aquatic Macrophytes in a Constructed Wetland for Municipal Wastewater Treatment FUTA JEET 11(1), 1 - 11

Antov, M. G., Sciban, M. B., and Prodanovic, J. M. (2012). Evaluation of the efficiency of natural coagulant obtained by ultra-filtration of common bean seed extract in water turbidity removal. Ecology Engineering 49, 48–52.

Betatache, H., Aouabed, A., Drouiche, N. Lounici, H. (2014). Conditioning of sewage sludge by prickly pear cactus (Opuntia ficus Indica) juice. Journal of Ecological Engineering 70, 465–469.

Bondy, S.C. (2010). The neuro toxicity of environmental aluminium is still an issue. Neuro- toxicology 31, 575 – 581

De Souza, M. T. F., Ambrosio, E., Freitas, T. K. F. S., Santos, L. B., Almeida V. C., and Garcia, J. C. (2014). The use of a natural coagulant (Opuntia ficus-indica) in the removal of organic materials of textile effluents. Environmental Monitoring Assessment 186, 5261–5271

Jodi, M. L., Birnin-Yauri, U. A., Yahaya, Y., Sokoto, M. A. (2012). The use of some plants in water purification. Global Advancement Resources. Journal of Chemical Material Science 1 (4), 71–75.

Mallevialle, J., Brichet, A. and Fiessinger, F. (1987). How safe are organic polymers in water treatment. Journal of America Water Works Association 76, 87–93.

Sciban, M., Klasnja, M., Antov, M. and Skrbic, B. (2009). Removal of water turbidity by natural coagulants obtained from chestnut and acorn. Bio- resources Technology 100 (24), 6639–6643

Teh, C. Y., Wu, T. Y. and Juan, J. C. (2014). Potential use of rice starch in coagulation–flocculation process of agro-industrial wastewater treatment performance and flocs characterization Ecological Engineering 71, 509–519.1983

Yin, C. Y. (2010). Emerging usage of plant-based coagulants for water and wastewater treatment. Process Bio-chem. 45, 1437–1444.

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Published

2019-11-16