There are three main factors affecting the dust removal effect of electrostatic precipitators: dust specific resistance, gas dust concentration and air flow speed.
- The specific resistance of the dust, the dust with a specific resistance between 104 and 1011 Ω•cm, the electric dust removal effect is good. When the dust specific resistance is less than 104 Ω·cm, because the dust has good electrical conductivity, after reaching the dust collecting pole, the speed of releasing the negative charge is fast, and it is very easy to induce a positive electric charge which is very similar to the dust collecting, because the same sex repels the dust. The composition moves along the outer surface of the plate, and the dust removal efficiency is also reduced.
- The concentration of dust in the gas, the dust concentration is too high, the dust hinders the movement of ions, and the corona current decreases. When it is severe, it is zero, corona is blocked, and the dust removal effect is drastically deteriorated. There are two kinds of electric charges in the electrostatic precipitator, one is the charge of ions, and the other is the charge of charged dust particles. The movement speed of ions is also higher, about 60~100m/s, while the moving speed of charged dust particles is lower, usually below 60cm/s. Therefore, when the dust-containing gas passes through the electrostatic precipitator, the amount of charge carried per unit time is less than that when it is cleaned, that is, the corona current at this time is small. If the dust concentration of the gas is very high, a large amount of fine dust particles are suspended in the electric field, which may cause the electrostatic precipitator to worry about a sharp drop in the halo current. In severe cases, it may approach zero. This condition is called corona blocking.
- The speed of the airflow, as the airflow speed increases, the dust removal efficiency decreases. The reason is that the wind speed increases, the time for the dust to stay in the dust collector is shortened, and the timing of charging decreases. At the same time, the secondary dust increase will increase as the wind speed increases. The magnitude of the electric field wind speed has a great influence on the dust removal efficiency. When the wind speed is too large, it is easy to generate secondary dust, which reduces the dust removal efficiency. However, the wind speed is too low, the electrostatic precipitator is bulky, and the investment is also increased. According to previous experience, the electric field wind speed should not exceed 1.5~2.0m/s, and the dust collector with high dust removal efficiency should not exceed 1.0~1.5m/s.