Maintenance of bag house dust collector

A trial run bag house dust collector:

During the trial operation of the new bag filter, special attention should be paid to check the following points:

1. The direction of rotation, speed, bearing vibration and temperature of the fan.

2. Whether the processing air volume and the pressure and temperature of each test point are consistent with the design.

3. The installation of the filter bag, whether there is any bag drop, loose mouth, abrasion, etc. after use, can be judged by visual inspection of the emission of the chimney after it is put into operation.

4. Pay attention to whether there is condensation in the bag room and whether the ash discharge system is unblocked. Prevent clogging and corrosion from occurring. When the dust accumulation is serious, it will affect the production of the host.

5. The adjustment of the cleaning cycle and the cleaning time is an important factor that affects the performance and operating conditions of dust collection. If the cleaning time is too long, the attached dust layer will be removed, which will cause leakage and damage of the filter bag. If the dust removal time is too short and the dust on the filter bag has not yet been removed, the filter operation will be resumed, which will restore the resistance quickly and gradually increase, and ultimately affect its use effect. At the start of operation, there are often unexpected circumstances, such as abnormal temperature, pressure, moisture, etc., which will cause damage to the new device. The test operation of the equipment directly affects whether it can be put into normal operation. If it is not handled properly, the bag filter is likely to lose its effectiveness quickly. Therefore, the test operation of the equipment must be careful and cautious.

Maintenance:

5.1 Always check the operation of control valves, pulse valves and timers.

The failure of the pulse valve rubber diaphragm is a common fault, which directly affects the cleaning effect. The equipment belongs to the external filter type, and the bag is equipped with a skeleton. It is necessary to check whether the parts fixing the filter bag are loose and whether the tension of the filter bag is appropriate. Whether the supporting frame is smooth to prevent abrasion of the filter bag. Compressed air is used for dust removal. Therefore, it is required to remove oil mist and water droplets, and the oil-water separator must be cleaned frequently to prevent malfunction of the movement mechanism and blockage of the filter bag.

5.2 Prevent condensation

During use, it is necessary to prevent the gas from cooling below the dew point in the bag chamber, especially when using the bag filter under negative pressure. Because the shell often has air leaking in, the air temperature in the bag room is lower than the dew point, and the filter bag will be damp. As a result, the dust is not loosely attached to the filter bag, but sticky, blocking the fabric holes and causing cleaning. The ash failure causes the pressure drop of the dust collector to be too large and cannot continue to operate, and some paste bags can not be dusted.

To prevent condensation, the temperature of the gas in the dust collector and its system must be kept higher than its dew point 25～35℃ (for example, the dew point temperature of the kiln-grinding integrated machine is 58℃, and the operating temperature should be above 90℃). Ensure the good use effect of the filter bag. The measures are as follows:

⑴ Add raw material storage sheds. In the production of cement, various raw materials, fuels and mixed materials have different moisture content. If they are placed in a fixed shed to prevent rain, the moisture content of the materials can be greatly reduced. This is an effective measure to reduce the moisture content of the materials. This situation is relatively common in cement plants in southern my country, but some of the material storage sheds are too small, and some are not. Therefore, it causes certain difficulties in the use of bag filters.

⑵ Reduce air leakage. The air leakage in the gap of the dust collector body, and the air leakage of the bag filter body should be controlled below 3.5%. In the dust collector system, the air leakage of the process equipment, such as the closed ash discharge valve of the discharge port of the ball mill, the air leakage of the closed ash discharge valve under the dust collector, and the pipe flange connection, are often ignored by maintenance and management personnel. , Increased unnecessary air leakage and worsened the operating conditions of the bag filter.

⑶ The dust-containing gas should be evenly distributed in the precipitator to prevent eddy currents from appearing at the corners to reduce the amount of gas passing here, resulting in local low temperature and causing condensation problems.

⑷ Do a good job in the insulation and rain protection of dust collectors, pipes and other related parts. Practice has proved that good heat preservation measures can make the temperature difference between the inlet and outlet of the bag filter very small, which is an effective measure to prevent condensation.

⑸ Take appropriate heating measures. For example, installing far-infrared electric heaters and electric heaters in the dust collector, or adding a radiator in the bag room, can appropriately increase the flue gas temperature of the host.

⑹ Strengthen the temperature monitoring of the dust collector and the dust removal system in order to grasp the use conditions of the bag filter and prevent condensation.