The boiler keeps forming scale; what should I do?
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Fluidized bed boilers tend to form slag constantly; they can only burn one type of coal, and slag formation occurs whenever the coal is changed. What’s the reason? The boss is in urgent need
Those who have experience working on main pipes for fluidized bed boilers or possess relevant technical knowledge can get in touch with me.
What kind of coal do you usually use? Which coal causes coking when it’s used? If there are significant variations in coal types, the carbon molecular gasification combustion technology can solve your problems; it is also environmentally friendly (ensures compliance with emission standards) and energy-efficient (the combustion system saves 60% on electricity consumption).
It is best to upload a DCS diagram of the boiler combustion, along with the chemical analysis data of the coal fed into the boiler, so that the cause can be analyzed.
There are various reasons for this coking phenomenon. Given that coking occurs whenever you change the type of coal, it is very likely that changes in the ash melting point and composition of the coal are to blame, resulting in combustion temperatures that exceed the ash melting point. As for the specific areas where coking takes place, you haven’t provided any DCS data; therefore, it’s difficult to say if there are other factors at play.
Causes of coking: 1. Poor fluidization of the bed material, abnormal external circulation, and bed temperature exceeding the ash melting point. 2. The fuel fed into the furnace varies greatly, and the ratio of air to fuel is inappropriate.
Typical boilers are designed to burn a specific type of coal; once the type of coal is changed, a full analysis and trial operation are required.
Contact the design institute to find out what the parameters for boiler design are and what coal types are required!
5% moisture, 17% ash, 15% volatile matter, and a calorific value of 5800 kcal. Sulfur content: 5%. Due to the high sulfur content, switching to another type of coal – a coal with 3% moisture, 30% ash, 7% volatiles, 2% sulfur, and a calorific value of 4200 – causes coking. The melting points of the two types of ash are 1280 and 1240 respectively, with little difference.