Q1. [HW] a) The higher the temperature a boiler operates at, the more efficient the Rankine Cycle. What are two important factors that limit how high the temperature can go in a boiler? b) A steam power cycle is connected to a furnace burning bagasse from a sugar mill and is producing 100 MW of power from its turbine. The cycle has a thermal efficiency of 32 %. Heat is rejected from the cycle to a condenser which is cooled with water from a river. For part ii to iv ignore the work associated with the pump. i. Draw an overall diagram showing the major energy flows. ii. What is the heat input for this cycle? iii. How much heat is rejected through heat transfer to the river water? iv. Bagasse has a HHV of 17 MJ/kg. If 90% of the heat from combustion is transferred to the boiler, what rate of bagasse needs to be burned (in kg/s)?
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Different materials have different temperature limits, so the choice of materials for the boiler construction is crucial in determining the maximum temperature it can operate at. 2) Combustion limitations: The fuel being burned in the boiler also has a maximum Show more…
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