The kiln exhaust gas treatment of a 5000t\d production line of a company adopts LCM920-2×7D bag dust collector. The dust collector has 28 chambers and 4928 Φl60mm×6000mm specifications. Under the condition of high dust concentration, the dust collection effect is good, and the outlet dust concentration meets environmental protection requirements. This article describes some of the problems and solutions that arise during use.

The poppet valve is stopped due to insufficient compressed air

1. Analysis of the reasons: After the production line was put into operation in 2004, the lift valve repeatedly jumped. After careful investigation, it was found that there were two reasons:

1 The oil-water separator between the gas storage tank and the poppet valve is clogged with the filter element due to dirty air;

2 After the lifting valve is operated for a long time, the seal is worn, causing leakage of compressed air, resulting in insufficient air supply.

2. Solution:

1 Add a set of oil-water separators, one for each. When the filter element is found to be dirty, another set can be replaced to clean the dirty set;

2 In addition to timely replacement of the poppet valve seal, the following measures should be taken: the supply pressure of the poppet valve is adjusted between 0.25 and 0.5 MPa, ensuring that each poppet valve can operate within the specified time. The pressure is not suitable. If it is too high, it will easily aging the cylinder seal. When the leak point increases, the supply pressure can be appropriately increased. Ensure that the oil-water separator is supplied with oil. The oil supply speed should not be too small to avoid oil loss. In addition, add a certain amount of grease to the stem of the lift cylinder.

After the above treatment, there has been no accident of the dust collector jumping due to insufficient compressed air.

Dust collector bag damage

1. Analysis of the reasons: During the inspection in 2006, several bags were found to be damaged. However, it was found that the damage was suddenly increased to more than 50 during the inspection in 2007. It is suspected that the quality of the bag may be defective or has reached the service life. The bag was sampled and tested. The results showed that the air permeability, burst strength and breaking strength of the other parts except the damaged part were within the range of use. At the same time, it was found that the damaged part of the bag was almost 20 to 40 cm away from the bag mouth, and it was damaged from the internal wear. It is determined that the main reason should be related to the backflush system. First, the nozzle of the backflushing system is not correct, causing backflush deflection; on the other hand, the pressure of the backflushing compressed air is too large.

2. solution:

1 The modification of the injection system is carried out, and the transformation cost is high and the cycle is long, which cannot be completed within the normal maintenance period. After research, it was decided to add a sheath in the bag. This method is simple and easy to operate, and the cost is relatively low. In the 2008 Spring Festival inspection, a jacket made of ordinary white iron was installed for the damaged warehouse and the damaged bag.

2 The anti-blowing compressed air pressure is controlled between 0.25 and 0.35 MPa, which can clear the ash on the bag. If the pressure is too high, the service life of the bag will be affected. It can be adjusted by observing the change of the pressure difference between the inlet and outlet of the precipitator, so that the pressure difference is within the control requirement range (design pressure difference <1700Pa).

3 Adjust the blowing program to adjust the pulse width from 150ms to 250ms to reduce the intensity of the spray and reduce the wear of the bag.

After inspection in July 2008, it was found to be effective, and there was obvious wear on the installed sheath, indicating that the bag was well protected, and the pressure difference between the inlet and outlet of the dust collector was also within the design range.

3 Conclusion

Because it can't be replaced under the normal power-on state, when the bag is damaged seriously, it will not only cause the surrounding bag to accumulate material, but also can not be used normally. At the same time, it will cause the dust in the outer row to exceed the standard and pollute the environment. In addition, the cost of spare parts for bags is also high. This treatment not only saves costs, maintains the normal operation of the equipment, prolongs the service life of the bag, but also protects the environment.