What a TEASE

[Mark O'Brien]

I didn't realise that there was an evaporation step. I just re-read the article link that you posted some time ago. The article referenced, adsorption, IX, UF and the MCV for bacterial control.

I found a good video on space.com with a walkthrough of the system. I'm slightly surprised that the iodine feed is at the end of the process and not at the beginning due to the risk of biological fouling of the medio and UF membrane.

http://www.space.com/common/media/video/player.php?videoRef=081119_RecycledUrine&mode=

 

[hatman]

I can't actually view the video from here, due to firewall settings, but I assume it's the one with Bob Bagdigian explaining how it works, then the interviwer taking a sip of water that's been recycled.

Anywho, IX = Ion Exchange, this is the step where Iodine is added.
MCV = Microbial Check Valve, this is non-depleting iodine bed that prevents bacterial migration from the contaminated end of the system to the clean end in the reverse flow direction.
UF = UltraFiltration, though it isn't the nomenclature we usually use, as we have several filtration beds.

Actually, the other thing I have always found inetresting is that the filtration beds are also downstream of the recirculation pump in the Water Processor.

Biofouling does not seem to be a problem in the filters of the Water Processor. We have pressure sensors across the filter beds, so they can be replaced when they get clogged. I would venture to guess that one of the reasons to put the iodine introduction downstream is that it would be just one more chemical to be removed in the High Temperature Catalytic Reactor Bed, and then the iodine would need to be reintroduced downstream anyway. I think the idea is that biologic growth in the dirty end of the loop is fine, provided there is a means and method for preventing contamination beyond a certain point. Hence the iodinization (SP?) of the water before it goes into the storage tanks.

Yes, the evaporation portion of the process is where the nasty salts in the urine get left behind. This is probably the most complex part of the process, and it's not owned by us (though we did bid on it some 10 years ago). It's also the part that malfunctioned and got all of the media attention back in November (while at the same time our systems were working flawlessly).

Coincidentally, biofouling is actually more of a concern in the Electrolytic Cell Stack. Counterintuitively, we have a De-Ionizing bed as the the first step in that system to remove the iodine from the water coming from the Water Processor, since the iodine interferes with the chemical reaction that takes place there.

 

[Mark O'Brien]

Anywho, IX = Ion Exchange, this is the step where Iodine is added.
MCV = Microbial Check Valve, this is non-depleting iodine bed that prevents bacterial migration from the contaminated end of the system to the clean end in the reverse flow direction.
UF = UltraFiltration, though it isn't the nomenclature we usually use, as we have several filtration beds.

Ah yes, um actually I was the one that put in the abbreviations. The article didn't use them.

Coincidentally, biofouling is actually more of a concern in the Electrolytic Cell Stack. Counterintuitively, we have a De-Ionizing bed as the the first step in that system to remove the iodine from the water coming from the Water Processor, since the iodine interferes with the chemical reaction that takes place there.

That is counter-intuitive, I also assumed that the ultrafiltration is after the resin to catch any media leaking through in addition to particles that come in the untreated influent.

Hah! I defy the Trubinator to hijack this thread.

 

[Greg Truby]

So for all of you who have been reading this thread - I know you've been wondering to yourself: "what in billy-blue-blazes does this Mark O'Brien character do for a living that he is able to give the appearance of actually comprehending what Paul does for a living?"

I say we post our guesses and Mr. O'Brien can decide whether to simply respond yea or nay, or perhaps a warmer/colder or perhaps he can come up with a series of hints to breadcrumb us to the proper career guess.

I'll get the ball rolling. My best guess is that Mr. O'Brien is an out-of-work philosophy major that is presently making ends meet by working as a roadie for a travelling polka band and the occasional hunting & fishing wear catalog modeling gig. He is presently conducting hydroponic experiments in his basement to improve yield on his line of "herbal supplements" that he peddles online and this is what led him to an understanding of recycling waste water.

So, anyone else care to hazard a guess as to Mark's profession?

 

[hatman]

Ah yes, um actually I was the one that put in the abbreviations. The article didn't use them.

I know. But I figured other members not familiar with the acronyms might be interested in knowing...

That is counter-intuitive, I also assumed that the ultrafiltration is after the resin to catch any media leaking through in addition to particles that come in the untreated influent

The downstream end of the de-ionizing bed in the Oxygen Generator has a 5 micron screen to catch bed media. As far as the influent to the system... it's drinking water, fully treated by the Water Processor and very clean (actually, I think that one of the filter beds in the Water Processor is a 0.2 micron, but don't quote me on that... I didn't design the system, and I haven't owned/worked on those filter beds in several years). On page 3 of this article is a nice flowchart of the interconnected systems, minus the Sabatier (which you can mentally insert as collecting and processing the waste H2 and CO2).

Actually, a very interesting problem we had with influent water last year involved the alternate water source for the Ogygen Generator before the Water Processor was launched. It seems that NASA was providing the system wih fuel cell water, which is basically devoid of dissolved gases, which caused it to re-absorb the thermal protection bubble that we count on being coalesced on the Deionizing Bed screen.

Hah! I defy the Trubinator to hijack this thread.

So did you REALLY think that Greg would shy from such an obvious gauntlet?

My best guess is that Mr. O'Brien is an out-of-work philosophy major that is presently making ends meet by working as a roadie for a travelling polka band and the occasional hunting & fishing wear catalog modeling gig. He is presently conducting hydroponic experiments in his basement to improve yield on his line of "herbal supplements" that he peddles online and this is what led him to an understanding of recycling waste water.

So, anyone else care to hazard a guess as to Mark's profession?

I'm just glad that Greg assumes aeveryone reading this post has paid enough attention to know what I do. I'd hate to see what kind of muddle he would make from my profession, avocation and hobbies.

That being said, I seem to remember at least one past thread where Mark talked about what he does... which devolved into the two of us exchanging some professional commentary regarding water purification in that thread too. I leave it as an excercise for the the student to locate that thread and figure this whole thing out. Not that I think anyone but me, Greg and Mark are really paying much attention to this thread (in spite of what I said earlier about explaining some acronyms).

 

[cornflakegirl]

I'm paying attention. Although not necessarily understanding. It's fascinating!

 

[scottylad2]

Is he the original series of Flash Gordon? or Lost?

 

[Domski]

I switched off after about the first couple of posts but at a guess I'd say either Alchemist or Toilet Salesman.

Dom

 

[RoryA]

How does one hijack a serious discussion about taking the p1ss?

 

[Mark O'Brien]

I know. But I figured other members not familiar with the acronyms might be interested in knowing...

I honestly did think anyone else would be reading this. I thought this had evolved into the type of discussion you have with a random at the bar while on the road after a hard day of peddling hamster milking machines.

Actually, a very interesting problem we had with influent water last year involved the alternate water source for the Ogygen Generator before the Water Processor was launched. It seems that NASA was providing the system wih fuel cell water, which is basically devoid of dissolved gases, which caused it to re-absorb the thermal protection bubble that we count on being coalesced on the Deionizing Bed screen.

Nice catch. How did the problem get solved? Bubble cabin air through the water or just stop using the alternate source?

What type of analytical testing can they do up there to ensure water quality? I'm assuming that on-line instrumentation would be useful, but that they'd have to resort to wet chemistry methods.

So did you REALLY think that Greg would shy from such an obvious gauntlet?

Actually I am impressed by the hijacking. I kind of wish my profile didn't spoil some of the fun.