Design of Carbon Capture System Utilizing Wolffia globosa and CaO Derived From Waste Seashells With Continuous Real‐Time IoT ‐Based Monitoring

Abstract

ABSTRACT This study presents the design and implementation of a prototype‐scale hybrid CO 2 capture system that combines Wolffia globosa cultivation, mineral carbonation with waste seashell‐derived CaO, and real‐time IoT‐based monitoring. Waste seashells were calcined at 900°C to produce CaO, which was characterized by XRD and morphological FESEM and EDS analysis and was selected for mineral carbonation. The IoT system monitored changes in CO 2 concentration above the W. globosa tank, which were influenced by photosynthesis and respiration cycles. It also tracked CO 2 concentration after the mineral bed, where a consistent decrease of approximately 300 ppm relative to the inlet was observed under the tested conditions, with outlet readings approaching the lower bound of the sensor's specified accuracy (±[50 ppm + 5% of reading]). This decrease was attributed to CaO hydration and subsequent carbonation. Continuous measurements of CO 2 , pH, and temperature provided useful diagnostic information for interpreting system behavior. The results demonstrate the feasibility of integrating locally available waste‐derived CaO with biological cultivation and IoT‐based monitoring in a small‐scale laboratory prototype. However, a full net carbon balance, including calcination emissions and operational energy demand, was not included in this study. Therefore, the observed CO 2 decrease should be interpreted as local CO 2 uptake during the mineral carbonation step rather than confirmed net carbon removal.