In a steam power plant, high-pressure steam from a boiler is used to turn a turb
ID: 112841 • Letter: I
Question
In a steam power plant, high-pressure steam from a boiler is used to turn a turbine. After exiting the turbine, the steam, which is now at a lower pressure, is cooled before being pumped back to high pressure and returned to the boiler. Explain why this cooling step is advantageous, even though it involves the loss of energy as heat. In a steam power plant, high-pressure steam from a boiler is used to turn a turbine. After exiting the turbine, the steam, which is now at a lower pressure, is cooled before being pumped back to high pressure and returned to the boiler. Explain why this cooling step is advantageous, even though it involves the loss of energy as heat.Explanation / Answer
the major reason behind condensing spent steam than directly using it again as turbine feed is, it is difficult to achieve heat transfer with vapors. So much so that it is better to condense the spent steam, where heat transfer efficiency isn’t critical to function, and then put the condensate into a boiler which is being heated by combustion of gases, where heat transfer efficiency is critical to function due to high temperatures of combusting gases. Bear in mind that the temperature change to bring spent steam back to liquid water is much smaller than to bring water up to the turbine feed temperature.
advantages of a cooling system in turbine: