Precautions for using dust collectors in cement plants

Precautions for using dust collectors in cement plants

The dust collector in cement plants has the advantages of good dust removal rate, easy operation and maintenance, and meeting standard emissions. More and more dust prevention systems are adopting it, but bag filters are not used anywhere, and special attention should be paid under the following conditions. Regularly discharge impurities such as oil and water from the oil-water separator and dust collector fan twice a week; Replace the dust removal bag every two years and check the wear of the bag at any time. If any damage is found, replace it promptly; If there is a horizontal dust removal pipeline, open the cleaning hole regularly every year to clean the accumulated dust inside the pipeline. When setting the pulse cleaning cycle of the dust collector, it is better to ensure that the dust collector works at a stable pressure and the pulse cleaning cycle time is set to be long. The pulse cleaning time should be set to prevent the initial dust from falling off, and the cleaning time should be set to be short. If the initial dust layer is insufficient, the cleaning cycle can be extended for compensation. If pressure difference control is used, the stability of the inlet and outlet pressure settings of the dust collector can be improved.

Discussion on the main structure of dust collectors in cement plants:

1、 Anti blowing dust cleaning mechanism: including rotary arm, blowing port, loop anti blowing mechanism, circulating air duct, anti blowing duct, anti blowing machine, and rotary arm deceleration mechanism.

2、 Lower box: including positioning support frame, ash hopper, star shaped ash discharge valve, and support.

3、 Medium box body: including flower board, filter bag, filter bag frame, filter bag guide, filter chamber cylinder, dust containing gas inlet and inlet hole.

4、 Upper box: including dust collector cover, rotating cover removal device, cleaning room, bag changing hole, observation hole, purified air outlet.

When the dust collector in the cement plant stops running for a long time, in addition to cleaning all the dust, before the system cools down, all the moist gases in the bag chamber should be emptied and replaced with dry air. In the operation of the dust collector, if the emissions exceed the standard and the operating pressure of the dust collector is lower than the design, it may be due to insufficient initial powder layer on the surface of the filter bag. The reasons may be that the filtration speed of the filter bag is too high, the cleaning cycle of the filter bag is too short, the pressure of the injected compressed air is too high, and the load capacity of dust is reduced. Excessive filtration speed will increase the dust discharge rate, and excessive filtration gas speed will cause the initial dust layer to break and the dust to impact the filter bag, resulting in excessive wear. If the filter bag is cleaned too many times at this time, it is easy to cause the fabric of the filter bag to loosen, which will lead to excessive emissions from the dust collector.

The following precautions should be taken when operating the dust collector in a cement plant:

1、 If the temperature exceeds 350 degrees, the bag filter cannot be used directly because the temperature is too high, and the bag filter is difficult to withstand and may burn out. Even if a dust collector is used, it cannot withstand the high temperature of 350 degrees. Cooling measures need to be taken before high-temperature smoke enters the bag filter.

2、 Collecting too much oil is not suitable for using bag filters, as the humidity is too high. Smoke containing excessive oil often leads to adhesion between filter bags and filter materials.

3、 If the humidity is low, the filter bag in the bag filter can be selected as either a filter bag or a bag filter, and necessary insulation measures should be taken to prevent moisture in the gas from condensing.

The cover of the dust collector in the cement plant is divided into multiple pieces, which can be opened freely for easy bag replacement and maintenance. After several designs, the inlet concentration does not need to be limited to 15 grams/m3. Even if it is 150 grams/m3, there is no need to add a cyclone dust collector. This device has the function of a cyclone dust collector, but there is no resistance from the cyclone dust collector. By using the resistance of the dust collector as a signal, it is possible to automatically control the rotation back blowing for dust cleaning. Depending on the low inlet concentration, the dust cleaning cycle can be automatically adjusted. The dust collector in the cement plant is arranged in a cylindrical body using ladder shaped flat bags, with a simple and compact layout, and the filtration area refers to the elevation. Under the action of counter blowing, the trapezoidal flat bag has a large amplitude, and only one vibration is needed to shake off the accumulated dust, which is beneficial for improving the service life of the filter bag. Except in extremely cold regions, this dust collector can be installed outdoors. The dust collector in the cement plant adopts a high-pressure fan equipped with equipment for reverse blowing dust cleaning, which is not limited by the gas source conditions of the application site, has fewer vulnerable parts, is easy to maintain and operate, overcomes the disadvantages of compressed air pulse dust cleaning, has a large reverse blowing distance, can use long filter bags, fully utilizes space, and occupies a small area. The shell is designed according to the volute shape of the cyclone dust collector, which can play a local cyclone role and reduce the load on the filter bag. The shape of a cylindrical dome is uniformly stressed and has strong blast resistance.