November 29, Question 105 on Boiler Foundations: (A certain score will be given to the top 50)
Thread Content
True or False: The total heat released when 1 kilogram of coal burns is called the lower calorific value of the coal. () Thank you for your support. Correct answer: additional wealth gain of +5–8 points; incorrect answer: additional wealth gain of +1 point
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Incorrect) The heat released from complete combustion; however, coal generally contains moisture, and after the evaporation of this moisture which absorbs heat, it is referred to as the lower calorific value
Error. ----------------------------------------
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake)
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake)
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Incorrect) The heat released per unit mass of fuel when it burns completely is called the calorific value of the fuel. The higher calorific value refers to the total amount of heat released when 1 kg of fuel burns completely, including the latent heat of vaporization released as the water vapor in the exhaust gases condenses into water. The lower calorific value of a fuel is obtained by deducting the latent heat of vaporization of water vapor in the flue gases from its higher calorific value.
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake)
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake)
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake)
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake) The lower heating value of coal refers to ； ----It refers to the heat generated when coal burns in air at atmospheric pressure, minus the latent heat of vaporization (evaporation heat) of the moisture present in the coal – namely, the water oxide produced by the combustion of hydrogen in the organic components of the coal, as well as the free water and bound water contained in the coal – leaving behind the actual heat that can be utilized.
The total heat released when 1 kilogram of coal burns is known as the lower calorific value of the coal. (Mistake)