Circulating fluidized bed boiler

Is there a problem with the blowing process? Too much dust has accumulated in the bags, increasing the resistance. What is the pressure difference in your dust collector right now?

800 Pa – this resistance is within the normal range. For the bag filters we use, spraying usually starts at around 1100 Pa to 1200 Pa

What factors can cause such a large pressure difference at present? How can one determine whether the bag has suffered from thermal aging, and what are the methods for doing so?

This post was last edited by pzhmotor on 11-11-2017 at 11:53. An experience pressure difference of 800 Pa is within the normal range; it is recommended to verify this (an on-site gauge can be installed)； It is necessary to determine whether the inlet pressure of the exhaust fan is appropriate (as it is negative pressure) by considering the data obtained during cold-state testing, the negative pressure values during operation, as well as the current drawn by the exhaust fan. In addition to the backwashing effect mentioned on the second floor, the factors that affect the dust removal efficiency and resistance of bag filters include air pressure and whether the pulse valves are functioning properly. To determine whether the pulse valve is functioning properly, one can measure the temperature of the air distribution pipe; if it remains cold at all times, it indicates that there is a hole inside the pulse valve ； During backwashing, crouch on site and listen to see if there are any noises; if not, there is a problem with the solenoid directional valve. The reliable operation of the lift valves is also an important factor – during backwashing these lift valves are closed, and they need to be opened again after backwashing, otherwise the flow area will decrease, affecting the negative pressure. If it has been aged under high temperatures, bag punctures usually occur. Check whether the dust particle concentration shown by your online monitor is within normal ranges (installation of such monitors is now required).

If the resistance increases, should one consider replacing the filter bag, or taking it out to clean it? Backflow can blow away some of the dust, but a small amount still remains in the pores each time, causing the pores of the filter bag to become increasingly clogged.

To conduct data comparison, such as the current of the exhaust fan under normal operating conditions, the negative pressure at the inlet and outlet of the dust collector, and the differential pressure of the dust collector – what are these values currently? A comparison makes it clear at a glance.