Abstract
Pure uncontaminated water does not occur in nature. Clean, fresh drinking water is essential to human and other life. Potable water should be free from heavy metals, turbidity, organic compounds and pathogens. Conventional treatments of water often include sedimentation, filtration and disinfection. Coagulation is one of the key process to remove colloidal particles and colour from water. The chemicals used for the process are called coagulants. Among the coagulating agents used in water treatment, ferric sulphate or alum (aluminium sulphate) is some of the most widely used salts. Aluminium is strongly neurotoxic and may be involved in the development of Alzheimer’s disease. Recently, these problems calls out for a tremendous amount of research to be conducted to identify robust new methods of purifying water at lower cost and with less energy, while at the same time minimizing the use of chemicals and impact on the environment. Hence this review presents the efficiency of some natural coagulants used by humans throughout history in treating drinking water. The review concludes that natural coagulants have a bright future and would work wonders in blended form.
Keywords: Chemical coagulants, coagulation, convential treatment, plant based coagulants, turbidity, water treatment.
Graphical Abstract
37