Asphalt is a commonly used high-viscosity organic chemical material, widely utilized in various fields. From a classification perspective, asphalt can be divided into petroleum asphalt, coal tar pitch, and natural asphalt. During the production and manufacturing process in asphalt plants, a large amount of asphalt fume containing fine tar particles is often generated due to heating. The fume contains organic exhaust gases such as carbon ring hydrocarbons, ring hydrocarbon derivatives, and various other compounds, which not only pollutes the atmospheric environment but also poses a threat to human health. Therefore, it is necessary to purify the asphalt fume to meet emission standards before discharge.

Characteristics of flue gas in asphalt flue gas system

(1) The main flue gas consists of smoke from the combustion of heavy oil or diesel, as well as dust, water vapor, and asphalt fume generated during the drying process of sand and stone.

(2) Due to the large dust particles at the air outlet, a primary inertial dust removal process must be added. This not only protects the filter bag from sparks, but also allows the recovered fine powder to be reused.

(3) The temperature of the dust-laden gas exiting the drying and heating roller and entering the bag filter is generally between 150-190℃. In asphalt plants, moisture in sand, stone, and aggregates is a common issue, which increases the humidity of the dust-laden gas.

(4) The heating and drying system for materials fully heats the aggregates through oil injection combustion. A small amount of physicochemical oil burns insufficiently and enters the bag filter along with dusty gas, which can easily cause bag sticking. Therefore, when selecting filter bags, the above factors should be considered to ensure stable operation of the system. We recommend using NOMEX, aramid, and their composite filter materials.