How does an electrostatic precipitator (ESP) work?

ESPs remove particulate matter from flue gas using electrical forces. Gas passes through ionizing section where corona discharge imparts negative charge to particles. Charged particles migrate to grounded collecting plates under electric field (30-75 kV). Collected particles are removed by rapping into hoppers. Collection efficiency follows Deutsch-Anderson equation, depending on migration velocity, plate area, and gas flow. ESPs achieve >99% efficiency for particles >1 micron, with low pressure drop (<25mm WC) but high capital cost.