Three elements of pulse injection of bag filter

The dust removal system of the pulse bag filter is mainly controlled by three elements, that is, the injection pressure, the injection cycle and the injection time. The setting of these three parameters directly affects the operation of the dust collector.

1、The blowing pressure refers to the compressed air pressure that is pulsed by the bag filter. The greater the blowing pressure, the more secondary airflow is induced, the greater the back-blowing velocity formed, the better the dust removal effect, and the more obvious the pressure drop of the bag filter. When the spraying interval and spraying time are unchanged, the spraying pressure increases, and the dust concentration at the inlet can be increased accordingly. However, if the blowing pressure is too high, excessive dust removal will also occur, which will affect the purification efficiency, that is, the bag filter will appear instantaneously “ashing up”. At the same time, air consumption increases and energy is wasted. It can be seen that the blowing pressure is too low or too high will affect the filtering effect.

2、The length of the injection cycle directly affects the pressure drop of the dust collector. For the pulse bag filter adopting timing control, the spray interval is set by the pulse controller, and the timing spray (open loop control). By adjusting the pulse interval, the pressure drop of the bag filter can be basically maintained at a stable operation. Under the condition that does not affect the normal operation, the pulse interval should be extended as much as possible, which can reduce the consumption of compressed air, and can also reduce the damage of the pulse valve diaphragm and filter bag, and prolong the service life. Extend the spray interval, although the power consumption of the spray system is less, but the pressure drop of the dust collector increases too much, which will increase the power consumption of the induced draft fan.

3、Blowing time (also known as pulse width) is the time for the pulse valve to open and blow. Generally, the longer the blowing time, the more compressed air will be injected into the filter bag, and the dust removal effect will be better. However, after the blowing time is increased to a certain value, the effect on the cleaning effect is not obvious.