The heat transfer of fuel in the boiler.
Answer to Problem 62P
The heat transfer of fuel in the boiler is
Explanation of Solution
Express the number of moles of carbon.
Here, molar mass of carbon is
Express the number of moles of hydrogen.
Here, molar mass of hydrogen is
Express the number of moles of oxygen.
Here, molar mass of oxygen is
Express the number of moles of nitrogen.
Here, molar mass of nitrogen is
Express the number of moles of sulfur.
Here, molar mass of sulphur is
Express the total number of moles.
Here, number of moles of carbon, hydrogen, oxygen, nitrogen and sulfur is
Express the mole fraction of carbon.
Express the mole fraction of hydrogen.
Express the mole fraction of oxygen.
Express the mole fraction of nitrogen.
Express the mole fraction of sulfur.
Express the heat transfer from the combustion chamber.
Here, number of moles of products is
Express the enthalpy change of sulfur dioxide between the standard temperature and the product temperature.
Here, specific heat constant pressure is
Express the heat transfer of fuel in the boiler.
Here, number of moles of carbon, hydrogen, oxygen, nitrogen and sulfur is
Conclusion:
Refer Table A-1, “molar mass, gas constant, and the critical point properties”, and write the molar masses.
Substitute
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Express the combustion equation.
Here, stoichiometric coefficient of air is
Express the stoichiometric coefficient of air by
Substitute
Refer Equation (XVI) and write the number of moles of reactants.
Perform unit conversion of temperature at state 2 from degree Celsius to Kelvin.
Refer Equation (XVI), and write the number of moles of products.
Here, number of moles of product carbon dioxide, water, oxygen, sulfur dioxide and nitrogen is
Take the temperature at standard condition as,
Substitute
Refer Appendix Table A-18, A-19, A-20, A-23 and A-26 and write the property table for products and reactants as in Table (1).
Substance |
|
|
|
0 | 8682 | 11,711 | |
0 | 8669 | 11,640 | |
9904 | 13,356 | ||
9364 | 13,372 | ||
Substitute the values form Table (I) into Equation (XII) to get,
Substitute
Hence, the heat transfer of fuel in the boiler is
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Chapter 15 Solutions
Thermodynamics: An Engineering Approach
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