Engineering atomizers for intensified carbon capture: A comparative performance study

Efficient Post-Combustion Carbon Capture (PCC) requires process intensification, realized by optimizing mass transfer at the gas-liquid interface. Within spray-column contactors, atomizers play a crucial role in this effort, yet a systematic engineering framework for their design, selection, and performance comparison under PCC-relevant conditions remains a significant gap. This study addresses this by designing, fabricating, and experimentally evaluating seven diverse single-fluid and twin-fluid atomizer types. A novel comparative methodology was employed, ensuring all atomizers were assessed under identical liquid flow rates and matched total energy input levels, enabling an unbiased and application-focused performance analysis across key metrics: droplet size distribution (DSD) uniformity, spray cone angle ( SCA ), atomization efficiency ( η A ), specific energy consumption, and entrainment risk ( IV e ). Our findings provide design guidance for intensified PCC. Optimized single-fluid atomizers (e.g., SH, FF, HC, FC) demonstrated superior energy efficiency ( η A > 2%, specific energy < 300 J/kg), representing a threefold improvement over typical twin-fluid designs, while maintaining low entrainment risk ( IV e < 5%) and robust op e ration. In contrast, twin-fluid atomizers (EFF, IMP) achieved the finest droplets but at significantly higher energy penalties (up to 900 J/kg) and substantial entrainment risk (up to 30%), rendering them less suitable for large-scale PCC without extensive downstream separation. Crucially, the study also validates a methodology for engineering atomizer geometry to achieve specific SCA independent of flow rate, offering better control for reactor optimization. This work delivers essential data and a validated, application-driven design methodology to accelerate the development of compact, energy-efficient, and sustainable spray-column PCC systems. • Custom-designed atomizers enable unbiased performance comparison for spray columns. • Single-fluid atomizers show superior energy efficiency and low entrainment risk. • Specific energy use is up to three times lower for single-fluid atomizers. • Atomizer geometry engineered to control spray angle independent of flow rate. • Provides a design guide for intensifying gas-liquid contactors.