Electrostatic precipitator having a spark current limiting resistors and method for limiting sparking
View Patent ↗An electrostatic precipitator including: a collecting electrode in a gas passage; a discharge electrode in the gas passage and separated by a gap from the collecting electrode; a power supply applying a voltage to the discharge electrode, wherein the voltage establishes an electric field between the discharge electrode and the collecting electrode to ionize gas flow in the gap, and a resistor in series with the discharge electrode and having an effective resistance in series with the discharge electrode of at least 50 Ohms.
1. A method mitigating sparking in an electrostatic precipitator having a discharge electrode, a collecting electrode, and at least one resistor in series with the discharge electrode the method comprising:
applying a current to the discharge electrode to form a voltage potential between the discharge electrode and collecting electrode;
flowing a gas through the precipitator and through a gap between the discharge electrode and the collecting electrode, wherein the gas is ionized b the voltage potential;
collecting charged particulates in the gas on the collecting electrode to remove the particulates from the gas;
when a spark forms between the discharge electrode and the collecting electrode, reducing current flowing through the electrode by dissipating current in the at least one resistor;
wherein the discharge electrode is a plurality of discharge electrodes arranged in sets and the method further comprises selecting a first resistor in series with a first set of discharge electrodes to have a higher resistance than a second resistor in series with the second set of discharge electrodes.
2. A method as in claim 1 further comprising arranging the sets of discharge electrodes in the precipitator such that the discharge electrodes in the set experience substantially similar levels of dust burdens.
3. A method as in claim 1 further comprising applying current with a single power supply to the discharge electrodes in the first and second sets.
4. A method as in claim 1 wherein selecting the resistors includes determining a resistance value for the first resistor which applies a voltage to the discharge electrodes in the first set suitable for a dust burden experienced by the first set, and determining a resistance value for the second resistor which applies a voltage to the discharge electrodes in the second set suitable for a dust burden experienced by the second set.
5. A method as in claim 4 wherein selecting the resistors further includes selecting a first resistor having a resistance value at least 50 Ohms greater than the resistance value of the second resistor.