Coagulation/Flocculation Process Using Moringa Oleifera Lam Followed by Adsorption on Activated Carbon for Water Treatment Supply

Disinfection is the step responsible for the safety of the microbiological point of view in the treatment of drinking water. However, the chlorine used in this step may react with natural organic matter (MON) present in surface water producing trihalomethanes (THM), which are toxic and potentially carcinogenic. This study aims to evaluate the efficiency of coagulation/flocculation using natural coagulant Moringa oleifera Lam (Mo) full and defatted, followed by adsorption on activated carbon coconut palm. Assays were performed in Jar Test, using water from the river basin, PR, Brazil. Coagulant dosages were 50 mg L^{- 1}, 30 mg L^{- 1} and 50 mg L^{- 1} for Moringa Oleifera full (Mo), defatted by extraction with hexane (Mo(hex)) defatted and extraction with ethanol (Mo (et)), respectively. The adsorption step was performed on a column containing 150 g of activated charcoal, coconut palm followed by a post- chlorination step. After each step of the process, samples were collected to evaluate the removal efficiency of apparent color, turbidity and UV 254nm absorption compounds, as well as to assess the formation of THM. It was possible to verify that the treatment of coagulation / flocculation using natural coagulant Mo (et) followed by adsorption on activated carbon and post-chlorination was able to significantly reduce the formation of THM. All parameters remain below the limits established by Ordinance No. 2914/2011 of the Ministry of Health. It can be concluding that the process proposed may be an interesting alterative in order to reducing the formation of trihalomethanes.