Water Supply (Aug 2021)
Real-time monitoring as an adaptive strategy towards green treatment of textile effluent using biosorbent from Acalypha indica
Abstract
Performance of green treatment systems such as adsorption to treat textile effluents often suffers lack of longevity and efficiency due to the presence of complex compounds of varying reactivity. There is scope for improving the operational efficiency of such processes using real-time monitoring systems. The present study aimed to evaluate the performance of an activated biosorbent prepared from the leaves of Acalypha indica for treating textile industry effluent by simulating process control with real-time monitoring. Batch experiments were performed with synthetic and real-time dye effluents to identify the optimum conditions (pH = 3.0, dosage = 1.0 g/L; time = 1 h) for the highest adsorption capacity (6 mg g−1 and 2 mg g−1). The evaluation of physical parameters suggested best fit for Freundlich isotherm model and pseudo-second-order kinetic model. The LabVIEW-based simulation control system enabled close monitoring of pH and temperature during the process. Based on the inputs, an alteration of initial pH has resulted in substantial reduction in chemical oxygen demand (COD) (73.91%), turbidity (52.43%) and total dissolved solids (TDS) (19.43%). The average incremental increase was highest for COD (45.80 ± 0.06%) compared to TDS (10.13 ± 0.06%) and turbidity (−1.74 ± 0.03%) for varying dosage (3 g to 11 g). The proposed framework for incorporating a process-control-based monitoring system can help to achieve better performance. HIGHLIGHTS Activated carbon produced from the leaves of Acalypha indica as a biosorbent.; Adsorption isotherm provides best fit with Freundlich model.; Adsorption kinetics indicate that the textile effluent follows pseudo-second-order kinetics.; LabVIEW has been used for the measurement of pH and temperature of the effluent.; Adjustment of the initial pH led to substantial reduction in the COD, TDS and turbidity.;
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