Leak Detection Operation of Phosphor Powder for Dust Collection Bag in Asphalt Mixing Plant

Asphalt mixer dust filter bag fluorescent powder leak detection is generally carried out after the filter bag is newly installed, or when the smoke and dust discharge exceeds the standard, to detect whether there are leaks and ensure that the discharge meets the standard. If the inspected dust collector is used, turn on the cleaning system to clean the dust for about 20 minutes to improve the detection accuracy. In view of this situation and combined with the characteristics of the dust collector, we have formulated the following detection plan to help detect the exact location of ash leakage.

Preparations before leak detection:

1. Stop the machine to clean the dust and materials in the clean air chamber, so as not to interfere with the judgment;

2. Before starting powder feeding, turn on the cleaning system for about 10-20 minutes;

3. Prepare special fluorescent powder for leak detection, special fluorescent lamp for leak detection, filter glasses and marker pen.

Leak detection steps:

Please follow the following operating requirements as a guide to conduct leak detection operations. If the operating site conditions change, please adjust them according to the actual situation:

1. Under the condition that the ash cleaning system stops running, the induced draft fan is running at more than 60% opening (the standard is that the fluorescent powder can be inhaled without falling into the ash hopper), and the fluorescent powder is put into the opening of the air inlet duct of the dust collector;

2. The position of the phosphor input port should be about 6m away from the air inlet of the dust collector. Otherwise, the phosphor powder should be put into the dust collector from the ash hopper outlet or the ash hopper inspection door;

3. No special equipment is required to add phosphor powder from the feeding port, but the feeding time should not be too long. It is only necessary to pour the phosphor powder into the feeding port as normal, not the whole barrel to avoid sedimentation; generally, 50 kg of fluorescent powder The powder is controlled in about 3 to 5 minutes;

4. After the phosphor powder is added, the induced draft fan will stop within 10 minutes;

5. After about half an hour, open the clean air chamber;

6. After the phosphor powder is put in, turn off the main fan, open the top cover of the dust collector, and use fluorescent lamps to carefully check the joints of the flower board in the cleaning room, the interface point between the filter bag and the flower board, etc. When testing, the surrounding environment The darker the brightness, the more conducive to the leak detection work, so the effect of phosphor powder leak detection is the best at night;

7. Analysis principle: If a shiny powder is found in a certain position of the clean air chamber, it means that there is a leakage point nearby, and you should pay attention to check the position, distribution, quantity and direction of the powder, and mark it with a marker;

8. Observe the key positions: the four walls of the dust collector, the welding place of the steel plate and the surrounding of the cloth bag mouth;

9. If problems are found, they should be marked clearly and dealt with in time to avoid secondary pollution;

10. Note: Before entering the dust collector, check that the body should not be contaminated with fluorescent powder, so as not to interfere with judgment. It is suggested that the powder feeding personnel and the leak inspection personnel should be 2 persons respectively.

11. If there are many leaks, you can replace the new filter bag with green phosphor for secondary leak detection.