Slagging and Fouling Causes

Slagging and fouling is a core portion of our business at Efficient Fuel Additives.  Often times boiler fouling and slagging can be managed, or partially mitigated by combustion tuning.  Power Magazine featured an article which describes many of the combustion tuning modalities that can be investigated and utilized to reduce slagging and fouling.

The article discusses appropriate furnace exit gas temperatures in relation to ash fusion temperature as well as channelling of flue gas through the superheater section.  While these are obviously critical operational parameters, they cannot always be controlled to optimum specifications.

For example, boilers burning fuels that are not boiler designed specified fuels may not be able to achieve the appropriate differences between furnace exit gas temperature and ash fusion temperature while still maintaining proper heat balance.  Many boilers may be looking for alternative fuel sources for a variety of reasons such as lower cost, production or renewable tax credits, lower emissions, depletion of existing mines, etc. that force operators to consume alternative fuels.  When this occurs, slagging and fouling can be significant as a result of constraining factors within the boiler interacting with different ash properties.  

Finally, constraints such as NOX emissions limitations may force combustion modifications such as staged combustion leading to expanded reducing conditions throughout the furnace.

This is why Efficient Fuel Additives works not only to optimize combustion to reduce slagging while maintaining emissions compliance, but we also examine the ash properties to tailor a specific fuel additive program to meet each individual boiler's needs in a cost effective fashion.