Gas conversion, cubic meters to mass
Thread Content
For example, how do you convert 10,000 cubic meters of hydrogen and nitrogen into tons?
Divide the value by 22.4 to obtain kilomoles; then multiply by the molecular weight of the gas (the average molecular weight for a mixed gas) to get kilograms; finally, divide by 1000 to obtain tons.
Molecular weight of hydrogen × volume fraction of hydrogen + Molecular weight of nitrogen × volume fraction of nitrogen
It was the first time I saw a term like “hydrogen nitrogen gas”; I wasn’t sure if it was a typing error, so I used the molecular weight first and added “average molecular weight” in parentheses. The calculation of the average molecular weight requires composition analysis data, which is usually available; you just don’t know how to obtain it. Really not; one has to analyze it first. With the data on the components, it is calculated using the method from the fourth floor.
For nitrogen-hydrogen gas: generally, N2 accounts for 25.01% and H2 accounts for 74.97%, with other components being negligible. Thus, the average molecular weight of nitrogen-hydrogen gas is approximately: 28*25.01% + 2*74.97% = 8.5 g/mol. For 10,000 Nm3 of this gas, the molar amount is: 10,000 Nm3 ÷ 22.4 L/mol = 4.464*10^5 mol. Converting this to mass gives: 8.5 g/mol * 4.464*10^5 mol = 3.8 tons
You can ignore the molecular weight of the gas mixture; after obtaining the value in kilomoles, multiply it by each component’s volume fraction to get its respective molar amount, then calculate each mass and add them together
For nitrogen-hydrogen gas: generally, N2 accounts for 25.01% and H2 accounts for 74.97%, with other components being negligible. Therefore, the average molecular weight of nitrogen-hydrogen gas is approximately: 28*25.01% + 2*74.97% = 8.5 g/mol. For 10,000 Nm3 of this gas, the molar amount is: 10,000 Nm3 ÷ 22.4 L/mol = 4.464*10^5 mol. Converting this to mass gives: 8.5 g/mol * 4.464*10^5 mol = 3.8 tons. This method is correct and can be used to obtain an approximate value