Comparative study on treatment of wastewater using natural and chemical coagulant / Randy Randock Lawat and Nurul Izza Husin

The community are facing a serious issue regarding water scarcity due to the exponential population growth. There are various type of wastewater treatment technologies have been developed to ensure plenty of water supply and to meet the demand of clean water for moving towards sustainable development. Coagulation and flocculation processes are commonly used in a wide range of water treatment processes due to its simplicity and cost-effective approach. Chemical coagulants are commonly applied in the coagulation process for turbidity removal. However, it may leads to negative impacts toward health issues instead of natural coagulants. Generally, natural coagulants considered to be more environmentally friendly due to its biodegradability, renewability, non-toxicity and relative cost-effectiveness. This paper was review the effectiveness of natural coagulant versus chemical coagulant and to determine the mixing condition and settling time of the coagulant. The review process conducted based on systematic literature review (SLR) by applying SALSA method which helps to assess both quantitative and qualitative content analysis. This paper highlights the effectiveness of natural and chemical coagulants applied in different type of wastewater. The FTIR analysis proves the potential of natural coagulants in wastewater treatment due to presence of functional group such as carboxyl and hydroxyl group which could help in coagulation process. It was found that, each of the application of coagulants in different type of wastewater have different type of mixing conditions. Based on the evaluation, most of the mixing condition is around 100 rpm. The settling time for coagulation and flocculation show variation due to the different type of coagulants and wastewater. In general, it shows that the turbidity removal increases as the settling time increases. Based on the review, it can concluded the application of natural coagulants are feasible and reliable towards sustainable development.