NOVEL APPROACH TO COAGULATION STUDIES IN MILLIFLUIDIC REACTORS FOR LAUNDRY WASTEWATER TREATMENT

Millifluidic reactors are employed for the laundry wastewater treatment by coagulation using poly aluminium chloride (PAC) as a coagulant. This study marks the first attempt at coagulation within a millifluidic environment, exploring the effect of high surface-area-to-volume ratio on coagulation. Operating conditions such as the flow rate of liquid coagulant and laundry wastewater, variations in the length of the channel, and the comparison between helical and linear structural orientation were systematically investigated. The study revealed that increasing the number of helical turns while maintaining the same tube length reduces the radius of curvature, which enhancing mixing efficiency and improving turbidity reduction. Coagulation efficiency was significantly influenced by the number of turns, with the optimal condition observed at 50 turns where the final turbidity was substantially lower. Additionally, the effectiveness of PAC as a coagulant was highlighted, with a concentration of 175 mg/L resulting in final turbidity as low as 94 NTU. The findings emphasize the importance of optimizing the structural design of millifluidic reactors and the precise control of operating parameters to achieve effective wastewater treatment.