Integrated intelligent smoke management system: integrating electrostatic precipitation with PID-controlled air recirculation for charcoal-grill restaurant kitchens

Charcoal-grill restaurants can contribute to localized air pollution through emissions of particulate matter, including PM₂.₅ and PM₁₀, particularly in small kitchens with limited ventilation. This study developed and experimentally evaluated an intelligent smoke management system integrating a dual-stage electrostatic precipitator (ESP), PID-controlled multi-pass air recirculation, and a compact smoke-capture hood for small charcoal-grill restaurants. The prototype was tested in an enclosed kitchen with a volume of 25 m 3 under Single-pass and Recirculation operating modes at airflow velocities of 2 and 3 m/s using six paired experimental runs (n = 6). System performance was evaluated based on PM₂.₅ and PM₁₀ removal efficiency, particulate removal rate, Equivalent Clean Air Delivery Rate (CADRₑq), and electrical energy consumption. The results showed that the Recirculation mode at an airflow velocity of 3 m/s achieved the highest particulate-removal efficiencies, reaching 95.15% for PM₂.₅ and 95.50% for PM₁₀. These values were significantly higher than those obtained under the corresponding Single-pass condition (p < 0.001). Under this operating condition, the measured average system-level electrical power was 68.2 W, corresponding to an energy consumption of 11.4 Wh per 10-min experimental cycle. The equivalent Clean Air Delivery Rate (CADRₑq), estimated from the experimentally derived airflow and measured particulate-removal efficiency, was approximately 813.1 m 3 /h for PM₂.₅ and 816.1 m 3 /h for PM₁₀. These findings demonstrate that integrating a dual-stage ESP with PID-controlled multi-pass air recirculation improved particulate-removal performance under the specific experimental conditions investigated. However, because the system was evaluated at a single test site using six matched experimental runs, further validation across different kitchen environments and cooking loads, together with direct ozone and VOC measurements and long-term operational assessment, is required before broader commercial applicability can be established.