Oxygen Generator question
Pirate Pete
Posted 2008-11-07 4:54 PM (#21258)
Mess cooking

Posts: 5

Subject: Oxygen Generator question

How did the O2 gen separate the H from the O? Any A gangers out there that have specific knowledge of how this was accomplished?
609EM1
Posted 2008-11-08 1:18 PM (#21290 - in reply to #21258)


Senior Crew

Posts: 173

Location: Humboldt,Mi
Subject: RE: Oxygen Generator question

Pirate Pete - 2008-11-07 7:54 PM How did the O2 gen separate the H from the O? Any A gangers out there that have specific knowledge of how this was accomplished?

Since I wasn't an A-Ganger I shouldn't even answer this question,but everybody on board the 609 was required to know the basic operating principles of an O2 generator.

Here is an attempt to explain............

When an electrical current passes through water,the water breaks down into hydrogen (H2) and oxygen (O2). However,pure water does not conduct electricity so an electrolyte must be added to the water.In this case it is potasium hydroxide (KOH).The US Navy electrolytic oxygen generator (EOG) uses a 30% KOH mixture.The EOG has 16 cells in series and mass quantities of electricity at low voltage passes through them.About 1200 amps at about 2 1/2 volts if I remember correctly......it's been 40 years since I've seen an O2 generator.When the water breaks down into H2 and O2,one gas accumulates on the cathode of the cell and the other gas on the anode.The O2 is piped to the oxygen banks and the hydrogen is dumped overboard.Since a water molecule is two parts H2 and one part O2,twice as many H2 atoms have to be gotten rid of. If I remember correctly,each EOG (the 609 had two) would produce O2 at the rate of about 90 -100 standard cubic feet per hour (SCFH).
Pirate Pete
Posted 2008-11-10 9:03 AM (#21344 - in reply to #21258)
Mess cooking

Posts: 5

Subject: This I knew

That is the Qual answer, But, what I want to know is the Technical answer. After the gas is generated, what physically separates the gases prior to pumping overboard and to the O2 system.

We are having difficulty with the oxygen gas giving the ECU bad data while burning the hydrogen thru an engine. I suppose if the engine was a pre-emissions engine it would not be a problem.

609EM1
Posted 2008-11-10 9:30 AM (#21346 - in reply to #21344)


Senior Crew

Posts: 173

Location: Humboldt,Mi
Subject: RE: This I knew

Pirate Pete - 2008-11-10 12:03 PM That is the Qual answer, But, what I want to know is the Technical answer. After the gas is generated, what physically separates the gases prior to pumping overboard and to the O2 system. We are having difficulty with the oxygen gas giving the ECU bad data while burning the hydrogen thru an engine. I suppose if the engine was a pre-emissions engine it would not be a problem.

Why didn't you say so...

One type of oxygen generator currently being used aboard submarines is the Treadwell electrolytic generator. The individual cells of the Treadwell generator essentially comprise a wire-basket cathode wrapped with two layers of asbestos cloth and sealed within an outer metallic pressure vessel which serves as the anode. An asbestos membrane is positioned between the anode and the cathode to separate the oxygen and hydrogen gasses produced at the respective electrodes. However, severe operating conditions occurring within the electrolytic cells have been found to cause rapid decay and degradation of the asbestos membrane and the electrode screens, thereby resulting in the inefficient production of oxygen and hydrogen gasses.

Buff
Posted 2008-12-01 9:44 PM (#22049 - in reply to #21258)
Crew

Posts: 71

Location: Lakeview, OR
Subject: RE: Oxygen Generator question

High pressure nitrogen blanket keeps the H2 and O2 headers from mixing, giving the H2 pump a chance to discharge it overboard.

Buff
Lee Davenport
Posted 2009-02-07 12:53 PM (#24125 - in reply to #21258)
Crew

Posts: 92

Subject: RE: Oxygen Generator question

I remember qualifying on the O2 gen, and as I remember it, there was 50 VDC with a high current on the electrode. However, I have been known to be wrong. Your memory is probably better than mine...
Buff
Posted 2009-02-09 9:23 PM (#24162 - in reply to #24125)
Crew

Posts: 71

Location: Lakeview, OR
Subject: RE: Oxygen Generator question

Lee,
You're right on the money. The 50 VDC caused the electrolysis. The nitrogen was the inert gas blanket "in case".
Buff