The electrostatic precipitator works by using a high-voltage electric field to ionize the flue gas, and the dust charge in the air stream is separated from the air stream under the action of the electric field. The negative electrode is made of metal wires with different cross-sectional shapes, called discharge electrodes. The positive electrode is made of metal plates of different geometries, called a dust collecting electrode. The performance of an electrostatic precipitator is affected by three factors, including the nature of the dust, the structure of the equipment, and the velocity of the flue gas. The specific resistance of dust is an index for evaluating conductivity, and it has a direct impact on the efficiency of dust removal. The specific resistance is too low, and it is difficult for the dust particles to remain on the dust collecting electrode, causing it to return to the airflow. The specific resistance is too high, and the charge of the dust particles reaching the dust collecting electrode is not easy to be discharged. The formation of a voltage gradient between the dust layers will cause local breakdown and discharge. These conditions will cause the dust removal efficiency to decrease.
Compared with other dust removal equipment, the electrostatic precipitator has less energy consumption and high dust removal efficiency. It is suitable for removing 0.01-50 μm dust in the flue gas, and can be used in high flue gas temperature and pressure. Practice has shown that the larger the amount of flue gas processed, the more economical the investment and operating costs of using an electrostatic precipitator.
The electrostatic dedusting technology has the following advantages:
(1) High dust removal efficiency;
(2) Can purify a large amount of gas;
(3) Wide range of particle sizes that can be removed;
(4) It can purify dusty smoke with higher temperature;
(5) Simple structure, low air velocity and small pressure loss;
(6) Energy consumption is lower than other types of dust collectors;
(7) The electric precipitator can be controlled by a computer and operated at a long distance.