ABSA 4th Class Practice Exam 2025 – Your All-in-One Guide to Exam Success!

Fluidized bed boilers are designed to effectively burn fuels with high ash content, making them suitable for a variety of coal types that may not be ideal for traditional combustion methods. The unique operation of fluidized bed boilers allows for better mixing and combustion of fuel due to the fluidization of the bed material, which creates a more uniform temperature and enhances the retention of smaller particles, such as ash.

When it comes to coal with high ash content, fluidized bed technology can manage higher proportions compared to other boiler designs. The specified high ash content of 70% indicates that these systems can accommodate significant levels of non-combustible materials in the coal without substantial loss to efficiency or increased emissions.

The ability to utilize coal with such a high ash content is particularly beneficial in terms of resource utilization and can lead to more efficient waste management and energy production. Thus, the correct answer reflects the advantages of fluidized bed technology in using fuels that would typically be considered waste or less desirable due to their high ash content.