Cause of serious rust of dust remover, horizontal mixer

For most dust collectors, as long as the rust removal coating protection work is in place during manufacturing, the equipment should have no problem in long-term use. But there are four special circumstances in which the problem becomes serious:

1. High SO2 content and high moisture in flue gas are the main causes of corrosion. Because once there is dew in the wall, they will form sulfite, in the weak part of the protection, it will produce corrosion;

2. The temperature of smoke is too low to create conditions for the formation of acid and corrosion of SO2;

3. Some users have misunderstandings in their understanding. For example, the dust collector at the end of the kiln bag, in order to prevent the paste of the bag, the box body is made of external insulation, but for the clean air chamber, it is considered that the flue gas will be discharged out anyway, the four walls are not made of external insulation, resulting in serious condensation of flue gas here, resulting in serious corrosion that should not occur;

4, the top cover perimeter seal is not strict, there is cold air invasion, but also in the vicinity of dew and rust.

1, equipment design and manufacturing to take anti-corrosion measures

Appropriate anti-rust measures should be taken according to the properties of flue gas, especially the content of SO2 and H2O, including the rust removal level (generally Sa2.5), the selection of primer and topcoat, the number of coating layers and the thickness of each layer; And ensure the construction in place; The temperature resistance level of the paint should be higher than the possible Z high flue gas temperature to avoid coating failure due to overtemperature.

Like bag dust collector, in high corrosion conditions of the bag cage can not be used in general galvanized, but should be used spray, asphalt paint or high temperature and moisture resistance paint; The internal components such as clean air indoor wall and blowout tube should also be treated similarly, and can not be used for general coating.

2. Strengthen the sealing of the system

This method mainly includes the seal of the dust collector itself and other equipment and pipes in the dust collector system. Because the density of the dust collector itself depends on the casing, the quality of manufacture and installation must be guaranteed in order to keep the casing well sealed. And all the joints of the shell are welded continuously, and the sealing around the door is also made of heat-resistant silicone rubber.

3, reduce the wet content of gas

Reducing the moisture content of the gas can reduce the dew point temperature of the gas, but also as much as possible to raise the temperature of the gas, so that the temperature difference between the gas temperature and the dew point temperature increases. Practice has also proved that this empirical value is small, because many working conditions are difficult to predict, if the air leakage rate is relatively large, the gas temperature is better than the dew point temperature of more than 30 degrees.

For example, for kiln type and coal mill system equipment, we must do a good job of comprehensive external insulation, do not leave hidden dangers for dew, production operation to ensure that the operating temperature is 20~30℃ higher than the dew point, not only prevent bag paste, but also prevent dew rust.

4, reduce the air leakage rate of dust collector

Air leakage is also an important cause of dust collector corrosion, because air leakage is closely related to the negative pressure inside the dust collector, the greater the negative pressure, the more serious the air leakage will be. The positive pressure operation will not adversely affect the performance of the dust collector, but dust is easier to enter the dust collector, so it is necessary to improve its sealing structure. In this way, fan wear will not be so obvious.