Perry’s Chemical Engineers’ Handbook – are the heat of combustion data correct there?
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Today I checked the Perry’s Chemical Engineers’ Handbook; the physical and chemical data in it include information on heat of combustion. The heat of combustion for CH4 is -0.8026 J/Kmol×1E-09, which seems incorrect; the heat of combustion for CH4 is actually 35 MJ/Nm3! 1 Kmol = 1000 * 22.4 = 22.4 m3, right! It seems like the difference is too large! Did I make a mistake myself? ! Could some expert help answer this! ! Thank you! ! See the picture.
0.8026E9 J/kmol = 802.6 MJ/kmol = 802.6/22.4 MJ/Nm3 = 35.83 MJ/Nm3. The figure is correct; it matches what the original poster calculated as well. . What’s wrong? ?
It is 1E-09, which is negative, not positive. . .
The value should be negative when it’s placed below.
It’s ×1E-09. .
-It can be explained as 0.8026 J/(Kmol×1E-09)
Oh, that’s the right explanation then, thank you. . .
You don’t read these manuals very often on weekdays, right? For simplicity, the data tables for heat of combustion often show values that have been multiplied by or divided by powers of 10. In this table, the value 0.8206 means that it is the result of multiplying the original value by 10^-9; the table clearly indicates “x10^-9”, so the actual value should be 0.8206E9. If you are careful enough, you will realize that the calorific value of natural gas is around 8000–9000 kcal/Nm3, which is approximately 35 MJ/Nm3, as you mentioned. . . They’re all very basic things. I’d like to remind the original poster that I’ve read many of your posts, and your foundational skills aren’t solid enough. If you want to improve in your work, whether it’s in the chemical industry or environmental protection, solid foundational skills are essential.
x10^-9, which means it becomes a very small value; the answer given on floor 6 is correct. Also, thank you for the reminder. . .
x10^-9 is E-9, not E9. . .