During mixing asphalt mixture, asphalt mixing plant will produce a lot of gas, dust and combustion residues, with particle size of above 0.5 μm. If directly discharged, these dusts will cause serious pollution to the surrounding environment, and also affect nearby residents and crops, etc. Therefore, to meet the emissions standards, the smoke and dust must be collected by the dust collector system.

The early dust collector system can only remove large particles (> 5μm), dust removal rate is only 75% -85% generally. With the improvement of environmental requirements and dust removal technology, asphalt mixing plant has been reached emissions requirements by using secondary dedusting. And the methods of secondary dedusting include wet dust and bag dust collector.

The wet dust collector is relatively simple in structure, low cost, having spray-type, venturi-type and other types, and can achieve a certain dust collection effect. But it will lead to secondary pollution problem, because waste water will gradually be acidified by the flue gas of sulfur, nitrogen, etc, during the recycling waste water. The acidified water may have a corrosive effect on steel, will form a secondary environment contaminated if discharged arbitrarily, and so wet dust has been diminishing in asphalt mixing plant.

Collection efficiency of bag dust collector is higher, up to 99% or more, and can reach more than 99.99% for the dust above 0.5μm particle size; bag dust collector have a wide range of applications, can be used for different types of asphalt mixing plant, and the Airflow can be changed; it is adaptable, flexible, operating flexibility. Different functional bag can be suitable for different types of fuel such as diesel, heavy oil, gas and coal. When gas dust concentrations is larger in the entrance, the collection efficiency is little effected; compared with wet dust collect system, bag dust collector can be recycling of dust graded according to the thickness, and so it does not exist the problem of the sludge disposal and secondary pollution; compared with other collection system, bag dust collector has no complex ancillary equipment and technical requirements, which cost of building and cost of operation is low, and life long.

Therefore, the bag dust collector is the most commonly used, and also is best dust collector system of Asphalt Mixing Plant.