Filter media is very important for the filter, when we choose the media we need to consider the following factors.

1 Gas temperature

Gas temperature is an important factor in the selection of filter media. Usually less than 130 degrees centigrade of the dust-containing gas is known as normal temperature gas, more than 130 degrees centigrade of the dust-containing gas is called high-temperature gas. For the reason, the filter media can be divided into two categories that is below 130 degrees centigrade normal temperature filter and higher than 130 degrees centigrade high-temperature filter. Therefore suitable filter media should be chosen according to the temperature of flue gas. It is also the 130 degrees centigrade ~ 200 degrees centigrade known as the medium temperature gas, but it is high temperature type filter media that is widely used. The temperature resistance of filter media contains "continuous long-term use of temperature" and "instant short-term temperature". “Continuous long-term use temperature” refers to the long-term temperature that the filter can be applied for the continuous operation, which temperature should be used to select the filter media. "Instant short-term temperature" means that the maximum temperature of the filter media is not allowed to more than 10 minute per day, once the time is too long, the filter will be aging or softening deformation.

2 Gas humidity

The dust-containing gas is divided into three states according to relative humidity: relative humidity of gas below 30% is dry gas; relative humidity of gas between 30% -- 80% is general state; relative humidity of gas above 80% is the high humidity gas. For high humidity gas which is also in the condition of high temperature, especially dust-containing gas with SO₃, gas cooling will produce condensation. It will not only make the filter bag surface fouling and blockage, but also corrode structural materials, so we need to pay special attention to the gas humidity.

3 Chemical properties of gas

   Kiln gas and chemical waste gas often contain all kinds of acid, alkali, oxidants, organic solvents and other chemical components, which is often affected by the temperature, humidity and other factors. Therefore, the choice of filter media should be considered comprehensive.

Polyester fiber has good mechanical properties and acid and alkali resistance at room temperature, but it is very sensitive to water and gas, and it is easy to hydrolyze which lead to the strength declining. For this purpose, polyester fiber in the dry flue gas, its long-term running temperature is less than 130 degrees centigrade, but in the high moisture flue gas, its long-term running temperature can only reduce to 60-80 degrees centigrade.

In the selection of filter media, it must be based on the chemical composition of the dust-containing gas, seize the main factors and make a comprehensive consideration. Rotary kiln with vertical preheater and filter produced by ZK won praise from cooperation customers. Welcome customers all over the world come to visit our factory.