Patent ID: 7704302

Claim:
An electrostatic precipitator comprising: a first collecting electrode and a second collecting electrode both in a gas passage, wherein the second collecting electrode is downstream in a gas flow direction from the first collecting electrode; a first discharge electrode in the gas passage and separated by a first gap from the first collecting electrode, and a second discharge electrode in the gas passage and separated by a second gap from the second collecting electrode; a power supply applying a voltage to the first discharge electrode and second discharge electrode, wherein the voltage establishes an electric field between the first discharge electrode and the first collecting electrode to ionize gas flow in the first gap and between the second discharge electrode and the second collecting electrode to ionize gas flow in the second gap, and a first resistor in series with the first discharge electrode and having first effective resistance in series with the first discharge electrode of at least 50 Ohms, and a second resistor in series with the second discharge electrode and having a second effective resistance in series with the second discharge electrode, wherein the second effective resistance is greater than the first effective resistance.