Attempts were made in this study to examine the economic efficiency and circular economy of Corchorus olitorius L. and Garcinia mangostana as natural coagulants in the treatment of domestic wastewater along with synthetic coagulant Alum. To evaluate the economic efficiency, incremental cost-effectiveness ratio (ICER) was the method used in finding the most efficient treatment design, considering the cost and the effect of treatment which is the removal efficiency of the contaminant. Additionally, to assess the circular economy related to the two natural coagulants (C100 and M100), the results of measured values of the parameters under study were compared with the DENR standard (DAO-2016-08) to see if the values are within the specified standards. Based on the findings of the study, treatment combination with saluyot as a coagulant attained cost per unit gram per liter at PHP1.32 (A50C50), 1.08 pesos (A75C25) & PHP 1.56 (A25C75). It has turbidity removal efficiency of 84.15%, 83.47% & 80.27%, respectively. Moreover, with mangosteen as the coagulant, results obtained for cost per unit gram per liter of wastewater were PHP0.43 with a removal efficiency of 91.40% (A50M50), PHP 0.64 with a removal efficiency of 90.22% (A75M25), and PHP 0.22 with a removal efficiency of 88.87% (A25M75). Using mangosteen as a coagulant proved economically efficient compared to saluyot. Further, the circular economy assessment showed that pure natural coagulant has the potential to remove water pollutants with effluents acceptable to DENR standards.
