Analysis of 15 Reasons for Blockage in Pneumatic Conveying Pipelines
? ? Blockage of pneumatic conveying pipelines often occurs in the initial section below 150m from the outlet of the transmitter, such as the silo pump. This is becauseThe initial flow rate is low, the concentration is high, and the flow pattern is the most unstable. As the frictional resistance of compressed air during transportation affects the energy of compressed airThe consumption of quantity, the pressure inside the pneumatic conveying pipeline gradually decreases, the specific volume increases, the volume of compressed air expands, and the flow rate increases,Not easily clogged. The later part of the pneumatic conveying pipeline will be automatically dredged even if it is blocked, because the later section of the pneumatic conveying pipelineDao usually adopts an enlarged design due to high flow control, preventing an increase in pipe diameter, a decrease in concentration, and a high initial velocityDue to the design in the previous section, large particles tend to accumulate at the bottom of the pneumatic conveying pipeline. When the flow rate is within a certain rangeAt this time, the flow at the bottom of the pneumatic conveying pipeline can continue to be conveyed.
? ? There are many reasons for pipe blockage, such as the bending radius of the elbow being too small or not meeting the specification requirements when changing the pipe diameter. The key question isThe question is about speed control.
Blockage in pneumatic conveying pipelines may be caused by one or more of the following reasons.
1. Incorrect operation. During the conveying process, the compressed air was mistakenly turned off, causing the material in the pneumatic conveying pipeline to settle and be refilledPneumatic conveying pipelines are prone to blockage.
2. When the air compressor fails, the pressure and flow rate of the delivered air will decrease, or when the centralized air compressor station is used forAir supply, a large amount of gas will suddenly be used elsewhere, resulting in a decrease in the conveying air volume and blockage of the pneumatic conveying pipeline.
3. There is a leak in the air pipe between the air compressor and the silo pump or conveying pipe.
4. When designing the system, the pressure or flow rate of compressed air is too low, and the pipeline is not matched, resulting in the initial flow rate not being able to handle the materialFully suspended. In this case, blockage of pneumatic conveying pipelines often occurs.
5. The feed valve or exhaust valve of the bin pump leaks under conveying conditions. In the case of dual chamber operation, this leakage will not only prolongThe delivery time of the leaking bin pump may also cause blockage of the pneumatic conveying pipeline when transporting another bin pump.
6. The clearance adjustment of the warehouse pump pipeline is too large, resulting in high concentration of transportation and pipeline blockage.
7. Improper adjustment of the primary and secondary air in the warehouse pump resulted in high concentration and blockage.
8. Overcharging of the warehouse pump leads to poor material gasification and reduced material fluidity, which affects transportation.
9. The bag filter on the end ash bin of the pneumatic conveying pipeline is not functioning properly, and the excess ash on the filter bag cannot fall off,Causing excessive back pressure during transportation and blockage of pneumatic conveying pipelines.
10. Due to changes in materials, such as a decrease in temperature, an increase in particle size, changes in moisture and ash content or chemical compositionThe failure of the electrostatic precipitator caused by the system's inability to adapt to changing conditions.
11. Due to rainwater intrusion or spraying, materials become damp, adhere, and particles increase in size, resulting in increased frictional resistance during transportationThe pneumatic conveying pipeline is blocked.
12. The pneumatic conveying pipeline or air main valve is not fully opened, resulting in high local resistance or insufficient gas supply.
13. Poor gasification of the ash hopper leads to poor material fluidity.
14. There are foreign objects or blockages in the dust cleaning pneumatic conveying pipeline.
15. When the air compressor is in an unloaded state and the pump is started for delivery, it takes some time for the air compressor to reload, resulting in insufficient air supply system. During this period, the material flow rate in the delivery pipe decreases, causing sedimentation and blockage.