A boiler produces 5.4 tonnes/hour of steam at a pressure of 1.5 MPa and a temperature of 350°C. Feedwater enters at a temperature of 44.5°C. At exit from the economizer part of the boiler the temperature is 93.5°C. At exit from the evaporator part of the boiler the steam is 90 A % dry. Energy is supplied by 600 kg of coal per hour, which has a calorific value of 32 MJ/kg. The A/F ratio is 15 1. The temperature of the flue gas at exit from the the economizer part of the boiler is 210°C. The average specific heat at constant pressure of the flue gas in the economizer is 1045 J/kg.K. When the ambient temperature is 24°C: 7. [83.3 %] Calculate the efficiency of the boiler. Calculate the equivalent evaporation from and at 100°C per unit mass of fuel. 7.1 7.2 [11.9] 7.3 Draw up an energy balance, on a kJ/kg coal basis, with percentages of the total energy supplied. Jeconomizer 6.8 %, evaporator 62 %, superheater 15.5 %, to atmosphere 9.7 %, other Josses 7 %)

A boiler produces 5.4 tonnes/hour of steam at a pressure of 1.5 MPa and a temperature of 350°C. Feedwater enters at a temperature of 44.5°C. At exit from the economizer part of the boiler the temperature is 93.5°C. At exit from the evaporator part of the boiler the steam is 90 A % dry. Energy is supplied by 600 kg of coal per hour, which has a calorific value of 32 MJ/kg. The A/F ratio is 15 1. The temperature of the flue gas at exit from the the economizer part of the boiler is 210°C. The average specific heat at constant pressure of the flue gas in the economizer is 1045 J/kg.K. When the ambient temperature is 24°C: 7. [83.3 %] Calculate the efficiency of the boiler. Calculate the equivalent evaporation from and at 100°C per unit mass of fuel. 7.1 7.2 [11.9] 7.3 Draw up an energy balance, on a kJ/kg coal basis, with percentages of the total energy supplied. Jeconomizer 6.8 %, evaporator 62 %, superheater 15.5 %, to atmosphere 9.7 %, other Josses 7 %)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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