Natural gas calorific value
Thread Content
The calorific value of natural gas is generally 8500 KCal/Nm3. Does this value include the heat carried away by the water produced during the combustion of natural gas? For example, when 100 cubic meters of natural gas is burned at a controlled temperature of 800 degrees, how is the total heat released during combustion calculated?
This post was last edited by ylb913 on 2016-12-6 at 19:48. The heat of combustion is usually referred to in terms of its \"low calorific value\", meaning that the water produced during combustion is released in the form of steam. The corresponding “high calorific value” includes the latent heat released from the condensation of water vapor. I have done the manual calculations for natural gas combustion. First, one needs to know the composition of the natural gas; then the furnace temperature (which is already known to be 800°C). Next, there’s the heat brought in by the natural gas itself (for example, its enthalpy at 40°C – whatever the specific temperature is), plus the heat brought in by the combustion air (also its enthalpy at 40°C – again, whatever the specific temperature is). The total of these amounts equals the heat carried away by the products of combustion (the enthalpy of those products at 800°C), plus any heat losses.