The problem of scaling in boiler water treatment systems
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The boiler is a horizontal low-pressure double-tube steam boiler; the water used as feedwater is softened with cationic resin, resulting in a water hardness of basically 0. However, scaling has recently occurred – the scale is white in color, with a small amount of rust as well. Since the manufacturer has already started the furnace, it is not possible to take samples for analysis. With such low hardness, how does scale form? Where does scale in boilers mainly form? After lighting the furnace, the furnace water was taken. The boiler water is cloudy and has a dark yellow color; this is likely caused by rust. There is black sediment at the bottom of the bottle. The pH of the boiler water is 11.5; after filtration, it becomes a yellow, transparent liquid. Salt is added to the boiler water, and acid is used to adjust the pH; once it becomes acidic, the water starts to become cloudy, with a large amount of suspended particles appearing. Initially, it was suspected to be a silicate, but adding an appropriate amount of sodium fluoride did not cause any change. It dissolves in an alkaline environment, but precipitates in an acidic one. What is this substance?
Just now, when measuring the hardness, I added sulfuric acid and potassium persulfate to the boiler water and evaporated it until it was almost dry. A black, sticky substance appeared at the bottom of the beaker; it was very sticky and could hardly be scraped off with a key. Adding acid and alkali does not cause it to dissolve either, but the viscous substance can be removed more easily. Both acidic and alkaline aqueous solutions change color, turning reddish-brown, with black substances suspended in the water. Furthermore, the filtered boiler water is transparent; it becomes turbid when acid is added, but once an alkaline solution is added to make it alkaline, the precipitate does not dissolve. I’m not sure why I’m really stuck; I don’t know who can help me out. Thank you!
We use physical methods to prevent scaling in the boiler, without the need for chemicals or water treatment systems, thus ensuring the safe operation of the boiler. You can contact me at shcsb11@163.com
Why do I get the feeling that the reply upstairs is like someone selling fake medicine? Asks nothing and claims to cure all diseases. Similarly, regardless of the system conditions, it ensures no scaling. Do you know about the system? Do you know the characteristics of double-drum boilers? I have been working in circulating water systems for many years; without first going to the site to understand how the system is currently operating, I definitely won’t make any promises! As a forum, I hope the moderators can manage things better and prevent ads from being everywhere!
Because you are using traditional chemical treatment; as for genuine or fake chemicals, why do boilers still develop scale even when chemicals are added? We use physical methods for descaling, and we can guarantee that the boiler will not develop scale.
It’s hard to believe unless you see it with your own eyes. Those companies whose equipment is suffering from scaling issues that need to be resolved urgently, or whose production is affected by scaling, can get in touch. Once we see the actual results, we can discuss further.