Slagging: Problem Definition
Ash related problems cost the US utility industry up to $8.7 billion per year. A part of this cost is caused by slagging. Empirical techniques to predict slagging have not been successful. More fundamentally based techniques are being developed. At this point, the practical application of the more fundamentally based techniques need to be demonstrated.
This paper reviews the causes of difficult deposits and recommends work that might help control slag in boilers. This paper starts with a deposit that can not be removed and analyzes the cause of this difficulty working backward. We start with soot blowing, proceed to deposit temperature, deposit strength, deposit building, and end with deposit initiation.
Finally, we recommend studies on soot blowing. This effort is aimed not only at determining the mechanism of soot blowing but optimizing practical soot blowing. We also recommend studies on the causes of difficult, plastic, and hard to remove deposits.
KeywordsDeposit Temperature Compression Strength Flame Emissivity Coal Fire Plant Slag Deposit
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