Manual online soot cleaning operation of the waste heat boiler in hazardous waste incineration plants
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We have a hazardous waste incinerator equipped with a membrane-wall waste heat boiler. After operating for some time, the temperature at the boiler’s outlet rises significantly, and ash accumulates heavily on the boiler walls. We then carry out manual cleaning by using high-pressure water guns to wash the walls. How much damage can washing the boiler walls with water at high temperatures cause? The temperature of the boiler’s flue gas can reach up to 800 degrees, the boiler pressure is 30 bar, and the water temperature inside the furnace tubes is around 250 degrees.
It depends; usually it’s taken every 2 months, but sometimes it’s not clear either
Isn’t there an online rapping device for cleaning dust? :)
Is your online vibration cleaning effective?
It might be due to different operating conditions; we’re still okay I guess. It’s just too labor-intensive; a pneumatic hammer operating with 1.0 MPa compressed air is being used,,,
We use mechanical vibration; the motor drives the vibrator to rotate, with no air required. Are we talking about the same thing?
Personally, I don’t think it has much of an impact; there was a waste incineration boiler in which water was sprayed to cool the system when one of its channels failed to prevent overheating. However, I feel that long-term use must have an impact on the water wall.
It seems that abroad, water jets are used to clean the deposits on the surface of boilers
Firstly, flushing with high-pressure water inevitably causes damage to the boiler, which is manifested in two aspects: 1) the damage caused by water to the water-cooled wall tubes – a small amount of water causes minimal damage, but when it comes to high-pressure water, the volume of water used is too large; 2) the entry of large amounts of water into the boiler leads to a significant increase in the moisture content of the flue gases, which in turn results in increased ash accumulation and corrosion on the rear heating surfaces. Secondly, manual cleaning lacks reliability and safety, and it is also not possible to clean all the heated surfaces. Therefore, abroad, there are devices that operate fully automatically online to clean the water wall. Low-pressure room temperature water is used. The frequency of use varies greatly depending on the actual operating conditions of the boiler. After each use, ensure that the superheater inlet temperature drops by approximately 60–100 degrees (depending on operating conditions). It not only ensures the cleanliness of the water wall and its heat absorption capacity, but also reduces corrosion of the tubes caused by dust accumulation – there is no need to wait until overheating occurs before cleaning.
Rapping for dust removal is used in superheaters and the rear heating surfaces. There are mechanical and pneumatic rapping methods. Currently, the mainstream approach abroad is to use vibration striking for individual cylinders; that is, each vibration striking point corresponds to one cylinder, and PLC programming is used to control this process, with alarm mechanisms in place to indicate whether the vibration striking at each point is effective or not.