A 2000 cu m vessel contains liquid methanol and it needs to be purged to
prepare for vessel entry. It should be purged initially with nitrogen (98 %
nitrogen and 2 % oxygen from a membrane process) and then purge with
air to get the fuel composition down to 0.1 % of the TLV. Use sweep
through purging, assuming a pressure of 1 atm. 25 deg C, and the purging
rates (for nitrogen and air) are 10 cu m/min.
Determine a) the composition of fuel in the tank after draining, b) the
target fuel composition after purging with nitrogen (with 2 % oxygen), c)
the quantity of nitrogen sweep through gas required, and d) the quantity
of sweep through air required.
a) the composition of fuel in the tank after draining,