Frequent scaling of the smoke extractor; online descaling
Thread Content
Our factory’s flue gas turbines suffer from frequent scaling; in the past, they had to be shut down for maintenance once a month. Recently, we are considering carrying out online descaling – that is, shutting off the butterfly valves and gate valves to cool down the turbines, using steam to remove the scale, and then restarting the turbines after descaling by reopening the valves. I wonder if anyone here has experience with online descaling and what precautions should be taken. I’d appreciate any insights shared
Reply to 1# maque4113: The scaling rate of your smoke extractors is quite fast. Contact the catalyst manufacturer’s staff to conduct a joint analysis, as this will lead to a more effective solution； The main causes of scaling include steam quality, catalyst properties, and the metal content in the feed materials. The common types of scale consist of salts such as silicon, aluminum, and iron. Other factors contributing to scaling include the strength of the catalyst, the emission of components from the catalyst at high temperatures, steam contamination, and contamination from the feed materials. By taking samples of the scale for analysis, it is possible to determine its main components and identify how it entered the system; subsequent modifications can then be made to address this issue ； The scaling rate is related to the dust content in the flue gas; it is necessary to analyze whether this dust content is within the acceptable range, and if not, adjustments or modifications to the three-spinners are required ； For steam to be effective in removing scale, a certain linear velocity and vibration frequency are required; otherwise, the cleaning effect will not be significant
This isn’t a good solution; if handled properly, the smoke extractor can continue to be used, but it’s not a long-term fix. If not handled properly, it can cause damage to the leaves. We tried it before; it worked, but not for a long time. It mainly uses rapid cooling and heating to separate the scale from the blades. But it’s hard to say about dynamic balance.
In other words, if it’s unbalanced, will the troubleshooting required be more complicated?
Generally, the machine is stopped for maintenance; after performing maintenance while it’s still running, its dynamic balance is definitely disrupted, resulting in high vibration, and in that case the machine still has to be shut down. Also, your range hood is probably two-stage, right? By changing the level, all problems will be solved. The olefin reduction catalyst has high viscosity, making it impossible to control; the fundamental solution is to use a different stage.