The issue of adding fluxes in coal gasification
Thread Content
As the title suggests, could the flux added during coal gasification explode when heated and end up in the raw gas, thereby causing scaling in the gas and water pipelines? What are some good solutions to this kind of problem?
I don’t have a very thorough understanding of gasification systems. Do you know what types of scale exist?
Of course it will. Coal and limestone have different thermal stabilities; an excessive amount of limestone can be carried by the raw gas into downstream pipelines and scrubbers, causing serious blockages, especially in fluidized bed systems. It is best to switch to coal, or install a cyclone dust collector at the outlet of the gasifier, which can **reduce risks**.
Is there a specific value for limiting the amount of limestone added?
It depends on the quality of your coal; if the ash melting point of the coal is high, a relatively larger amount of limestone needs to be added. However, this amount generally doesn’t exceed 5% – adding too much isn’t cost-effective and is also not beneficial for downstream processes. If permitted, coal blending can be considered.
Could you explain it in more detail? Thank you!
I suggest you take a look at the chemistry of coal ash; once you read it, you’ll understand what’s going on