Abstract A portable three membrane type gas separator including an input region, and output region and two interstage regions defined between adjacent membranes. The second interstage region, closest to the output region, includes a pump or trap for pumping water vapor from the second interstage at a pumping speed which substantially exceeds the pumping speed of the pump or trap for nitrogen, whereby water vapor is prevented from overloading the high vacuum pump connected in gas communication with the output stage of the separator and any additional vacuum pump connected into the second interstage region of the separator. A suitable pump for pumping water vapor includes a desicant material such as zeolite, alumina or phosphorous pentozide.
The apparatus of Claim 1 wherein said means for pumping water vapor includes a solid desicant material.
Claim 2
Dependent Claim
21 words
The apparatus of Claim 2 wherein said desicant material is selected from the group consisting of zeolite, alumina and phosphorous pentoxide.
Claim 3
Dependent Claim
52 words
The apparatus of claim 1 wherein said first interstage region is evacuated to a partial pressure of the carrier gas in the range of 0.1 to 10 torr and wherein said second interstage region is evacuated to a partial pressure of the carrier gas in the range of 0.001 to 0.1 torr.
Claim 4
Dependent Claim
30 words
The apparatus of claim 1 wherein said three gas separating membranes are semi-permeable membranes which are relatively impermeable to permanent gases and relatively permeable to sample material to be separAted.
Claim 5
Dependent Claim
16 words
The apparatus of claim 1 wherein said three gas separating membranes are made of dimethyl silicone.
Claim 6
Dependent Claim
33 words
The apparatus of claim 1 including an evacuated gas analyzer connected in gas communication with the output region of said membrane gas separator for analyzing the gases passing through said membrane gas separator.