Gas Content: Volumetric Method
The Volumetric method uses a known mass of coal enclosed in a bomb of
known volume and the bomb is evacuated. A large gas chamber of known gas
pressure is attached to the bomb and the line connecting the two is opened.
The pressure is then monitored until there is no more change occurring.
The configuration for the connection is shown in the attached diagram.
The quantity of gas absorbed in the chamber is given by:
Qp = 1/w [PcV2 – P(V2 +
V1 – w/ec)]
Qp = quantity of gas absorbed at pressure p,
cc/g;
V1 = volume of bomb containing the sample, cm3;
V2 = volume of chamber containing gas, cm3;
Pc = initial pressure of gas in the chamber, kPa;
P = pressure of gas in the chamber and bomb after equilibrium, kPa;
w = mass of coal sample, g;
ec = helium density of coal, g/cm3
|
