Scrubber design question

spacemanspiff1974

Hello,

I have another basic rebreather question that didn't seem to fit with my last post.

What are the comparative disadvantages between an axial scrubber design (holes along the exhaust pipe) versus the type of scrubber where the exhaust pipe is solid, goes down to the bottom of the canister and the exhaust travels all the way back up through the scrubber media?

Please excuse me if I don't have my terminology correct. I'm still learning.

shell-back

I hate to hijack the post but just a question to all of you. I just took a trip to Home depot and it never fails , I start walking the isles picking up stuff that looks like or could be used for, well you know. From plumbing supply to soft water filters , to industrial hoses, Its like I am missing a bit of time. two hours later I walk out of the store and sit in the car wondering what it was I was there for .......OHh light bulbs.

This is a phenomena know only to me ?
is this known HBBO (home builder Black Out)
I thought I was over this when I sold the dolphins and pieces parts. It must stay with us, is it curably with the purchase of a ECCR or just shows different signs and symptoms.

__________________
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Billy Beal
SDITDI IT #3507
Rebreather World FIGJAM commitee member

Genesis

Happens to me all the time

__________________
"A venturesome minority will always be eager to get off on their own, and no obstacles should be placed in their path; let them take risks for Godsake, let them get lost, sunburnt, stranded, drowned, eaten by bears, buried alive under avalanches - that is the right and privilege of any free American."
http://www.denninger.net
http://www.diversunion.org/liability.htm - Fix the Diving Cert racket

caveseeker7

I think is called Hyperbitnia, too many bits on the shelves.
Symptoms range from loss of time, temporary Alzheimer like syndroms
like forgetting your spouse (much as that happens in strip clubs) to
total blackouts.

Good news is that you usually recover from the symptoms above
and the only lasting damage is usually to your wallet.

"Usually" is important here, as there are known cases where forgetting
the other half brought on serious bouts of hyperspousia that caused
considerably more and lasting damage than the initial hyperbitnia.

__________________
Cheers
Stefan



"It is still a good day if you are on the green side of the grass!

Su amigo Roberto!"

Sponsor Lou in Race For Life!

Genesis

I don't have a spouse, therefore I cannot suffer from hyperspousnia.

However, I can (and do) suffer from hypoSOnia from time to time... it must be the three scooters, deco bottles and an eCCR controller on the desk in the bedroom that's keeping 'em all away

__________________
"A venturesome minority will always be eager to get off on their own, and no obstacles should be placed in their path; let them take risks for Godsake, let them get lost, sunburnt, stranded, drowned, eaten by bears, buried alive under avalanches - that is the right and privilege of any free American."
http://www.denninger.net
http://www.diversunion.org/liability.htm - Fix the Diving Cert racket

caveseeker7

On the axial scrubber the gas enters the absorbant container on one end and exits on the opposite end. Examples are the Inspiration and Dräger scubber.

On a radial scrubber the gas goes either from the outside to the inside or from the inside to the outside through the scrubber bed. Examples are the PRISM and Ouroboros. Those are hence the ones that have holes in the "centerpipe" as well as the outside of the cannister.

Axial scrubbers have higher work of breathing but are less expensive to manufacture. Radial scrubbers have a lower work of breathing and are more expensive to build. Radials are also supposed to be more efficient and hence longer lasting.

I highly recommend Jeff Bozanic's "Mastering Rebreathers". While incomplete, it covers all the basics about rebreathers, different designs etc.

__________________
Cheers
Stefan



"It is still a good day if you are on the green side of the grass!

Su amigo Roberto!"

Sponsor Lou in Race For Life!

schford

I am struggling to visualise the question from the description....

But the 2 main types of scubber design are Axial and Radial - it would seem to me that the holes along the exhaust pipe design you are describing is a Radial scrubber with an in to out flow....a la the PRISM. eg the gas comes down the exchaust pipe into the middle fo the scrubber and travels out of a bunch of holes and across the radius of the scrubber...

Axial is typically a top to bottom flow (unless you have an anular axial a la MK 15)

Pros and Cons well it really comes down to your views on break through warning and flood tolerance not to mention flow direction!

It is the weight of CO2 absorbant at the end of the day that I think is the key factor (but then again what do I know!)

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koputai

Actually, it's usually bottom to top, just like the Mk15.
4 egg sample:
Inspiration, down the outside pipe, into the bottom of the scrubber, up thru the sorb, and out to the diver.
Draeger FGG/FGT, down the internal pipe, into the bottom of the scrubber, up thru the sorb, and out to the diver.
Well, come to think of it, it depends on the divers orientation in the water. If the diver is horizontal, Inspo flow is from one side to the other, Mk15 is bottom to top. If the diver is vertical in the water, Inspo flow is from bottom to top, and Mk15 flow is from one side to the other.

Jason M.

schford

yup absolutely - no idea why I wrote to top to bottom I meant bottom to top lol!

Probably teach me for posting whe I am tired!

__________________
Bailout and Kit Management account for Murphy's Law

The only bad question is one you did not ask and later wish you had.

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vid

a great book - but one question

the book refers readers to the "mightywords" website, where revisions would be posted - only that site went offline shortly after the book was published

Question - does any one know of another site where Jeff or others posted updates to the book's contents?

ta
vid