MDC/PDC bag dust collector adopts the combination of inertial dust collector and bag filter, so it has the function of two stage dust collection. Containing dust and gas first enters the room dust in advance, encounter barriers, forces the dust airflow direction changing dramatically, the coarse particles of dust due to the collision with obstacles and change the original direction of motion.
Work principle：
The combination of inertia dust filter and bag filter is used in MDDC/PDC sack-duster,which can achieve the second grade of ash removal. Dust air firstly enter the preremoving room, meet the designed obstacle, be forced to change its direction. The coarse grain changes direction because of the obstacle. Some of them will fall down into the hoppers, the left will attach the surface of the filtering bags along with the air flow. The purified gas will go through the bag type dust collector bags and get to purifying room, exhaust duct, and go out from the blowers.
With the dust powder adhered to the filteringbags increased, the resistance of dust filter go up and should be removed. The internal pulse air flow should be used to remove dust. The air flow can not only vibrate the bags, but also blow through them from inside to outside, which will achieve good ash removing effect. The shift of dust removing chamber is controlled by solenoid valve and completed through that compressed air drives the cylinder valve. The whole process of ash removing is done by back-flushing fan, pulse valve,pneumatic valve and dust removing control system.
Operation condition：
1．Driving resistance：
The driving resistance of work conditions with normal temperature and no loads is 10 to 50 mm water colomn. The driving with load is controlled in the range of 100 to 120mm water colomn.
2. Driving temperature：
Air inlet temperature is confirmed by material of filtering. Inlet temperature of needle felt or 208 industrial terylene filtering material should be less than <110℃. Normal driving temperature should be 10 centigrade higher than that of dew temperature.
3. Filtering speed：
Filtering speed (m/min) is the amount of air going through per unit area of filtring cloth in per unit time. The selection is decided by the character of dust powder, the request of choosing filtering material, types of the material and the way of removing dust. Filtering speed will not only decide the specification of dust filter, but also have effect on the efficiency, resistance of flow, removing dust efficiency. To guarantee high efficiency of dust filter and long life of filtering bag, filtering speed is better not over 1.0m/ min.
4. Selection of filtering material：
Anti static needle felt filtering material is used in explosion prevention dust filter of MDC series for coal mill. Nonwoven needle felt or 208 industrial terylene is in bag filters of PDC series. We can also prepare different filtering materials according to users’ different requests.