Hydrophobic Black Carbon Capture from Ship Emissions Based on a Charger-Coupled Wet Scrubber

Black carbon emissions from ships have been identified as a significant contributor to the accelerated melting of Arctic glaciers, and there has been a lack of standardized methods for controlling them. In this study, a comprehensive approach to address ship-based hydrophobic black carbon with simulated nanoparticles (SP-BCs) was developed through enhanced scrubbing by electrostatic charging. The charger-coupled wet scrubber exhibited significant improvement under a low flue gas velocity (1 m/s) and a low liquid-to-gas ratio (L/G ratio, 8 L/m3), where the collection efficiency of the nanoscale SP-BC was increased by over 25%. In addition, many SP-BCs escaped from the outlet of the conventional wet scrubber during a long period of spraying at high intensity. Applying an electrostatic charger, increasing the L/G ratio, and increasing the flow velocity could effectively suppress the escape of black carbon particles during prolonged cyclic spraying. Furthermore, the optimal electric field intensity for the charger was 6.5 kV/cm to ensure a long-term stable operation. The charger-coupled wet scrubber could achieve a minimum emission concentration of SP-BC as low as 4.48 mg/m(3), with a corresponding collection efficiency of 91.3%. The results have significant implications for low-resistance and high-efficiency black carbon emission control from ships.