If the boiler efficiency is 84%, what can be concluded about the heating value of the fuel?

The correct choice of 32,000 kJ/kg as the heating value of the fuel is concluded based on the relationship between boiler efficiency and the heating value of the fuel.

Boiler efficiency is defined as the ratio of the useful energy output from the boiler to the energy input from the fuel. In this case, with an efficiency of 84%, it indicates that 84% of the energy contained in the fuel is converted into useful steam energy.

To determine the heating value of the fuel, you can use the equation for boiler efficiency, which incorporates the heating value of the fuel. The higher the heating value of the fuel, the more energy it contains per kilogram, which subsequently leads to a higher efficiency if all other conditions (like combustion completeness and heat losses) are optimal.

For an efficiency of 84%, the selection of the heating value at 32,000 kJ/kg aligns with common values used in the calculations for typical fuels. In industrial applications, fuels with heating values close to this figure are often used, ensuring that the efficiency level meets operational standards and requirements.

The other values are either too high or too low to align with typical observed efficiency rates, making 32,000 kJ/kg the most reasonable choice reflecting a