Evaluation of Electrostatic Screen Battery for Emissions Control (ESBEC) with Diesel Emissions

We recently developed a novel diesel emissions control device, Electrostatic Screen Battery for Emissions Control (ESBEC), where diesel exhaust particles are collected onto metal screens using electrostatic principle. This paper focuses on further development of this technology: design and integration of a particle charger and testing of ESBEC with diesel exhaust. Two units - 0.038 and 0.152 m (1.5 and 6 inches) in diameter - were fabricated using 3D printing. Both units feature cylinder-shaped housing integrating the electrical charger and up to seven pairs of metal screens, which collect airborne particles. In the small-scale version, particles are charged by ions emitted from a carbon fiber brush, while in the large-scale version, this is done by using two tungsten wires traversing the cross-section of ESBEC in a crisscross pattern. Small-scale version showed average collection efficiency of 80% over a wide range of diesel exhaust mass concentrations (5 to 400 mg/m³) and 1.5 m/s diesel exhaust face velocity. When ESBEC was tested continuously for 6 hours with diesel exhaust concentration of 300-400 mg/ m³, it maintained collection efficiency of >95%. The pressure drop across ESBEC during those six hours increased only minimally. In the next step, the large-scale version was challenged with diesel exhaust of 200 mg/m³ concentration. ESBEC removed 71-99% of exhaust particle mass entering the collector at different temperatures (40-77 °C). In the near future, a full version of ESBEC will be fabricated from a heat-resistant material, and its performance will be compared with a conventional diesel particulate filter.