Low-Head Shower?

[Bancherd]

I took this picture from one of Dr. Hubert Chanson's publications.

Can we make something out of this?

Shower with low-head?

[PapaBear]

Quote: Originally Posted by Bancherd I took this picture from one of Dr. Hubert Chanson's publications. Can we make something out of this? Shower with low-head?

The water appears nearly to be all foam by the time it reaches the bottom step . Any info on the flow rate and dimensions on this piece of work? It looks like a very compact version of what I've been planning to build, but I seriously doubt I'd be able to duplicate that kind of aeration.

[bekko]

Bancherd,

This possibility was danced around in other threads recently. I think the problem in designing a low-head BS is that we do not really know what makes a BS work to begin with!! If the process would work with the media submerged, there would be a lot of options - such as the photo you posted. If the media cannot be submerged, then about all you can do is have fewer trays or spread the media out horizontally to lower the height. But, do you then have to increase the flow proportionally to keep the water's exposure to the media the same? Greg was talking about putting the BS in a sump (dry well), but you still have to pump the water up out of the sump so the pumping head is essentially the same.

There is a book called Dynamic Aquaria by Walter Adey which has a very in-depth discussion of what a rocky shallow stream (babbling brook) can do to water quality. There are some similarities with a BS. However, Adey's stream has a macroalgae component and, of course, it is not impacted by far infrared rays.

P.S. If I have offended anyone on either side of the BS pro/con discussion, then you misunderstood me. Don't want to re-open that wound.

-steve hop kins

[kingkong]

[quote=Bancherd]I took this picture from one of Dr. Hubert Chanson's publications.

Can we make something out of this?

Shower with low-head? [/QUOTE

My guess this demonstration shows a fluid (water) is a material continuum that is unable to withstand a static shear (to become deformed by forces tending to produce shearing strain by some obstruction). Water flowing over a drop forms a hole or a hydraulic. This demonstration shows organized fluid flow going from laminar to turbulent behavior due to the effect of stress created by disruption or interference (dropped steps).

[PapaBear]

[quote=kingkong
My guess this demonstration shows a fluid (water) is a material continuum that is unable to withstand a static shear (to become deformed by forces tending to produce shearing strain by some obstruction). Water flowing over a drop forms a hole or a hydraulic. This demonstration shows organized fluid flow going from laminar to turbulent behavior due to the effect of stress created by disruption or interference (dropped steps).[/QUOTE]

Good expanation of the science , but it still begs the question. Can we expect a similar effect if the steps are partially filled with submerged biomedia? If so the aeration created by the shear would more than overcome issues of anaerobic bacteria vs. aerobic in the bio.

[kingkong]

Quote: Originally Posted by PapaBear Good expanation of the science , but it still begs the question. Can we expect a similar effect if the steps are partially filled with submerged biomedia? If so the aeration created by the shear would more than overcome issues of anaerobic bacteria vs. aerobic in the bio.

I think a filter system requires very passive water flow compared to the example shown. We do not have much information about what we are seeing. Maybe someone can explain what this test really is but it looks like excessive fluid inertia or pressure being used which would push the filter or bio media, if in place, up, up and away.
What I would like to know is the reasoning of the cavitation or cavaties of air forming in the liquid being pumped in demonstration. It must be one of the following.
Vaporization
Air Ingestion
Flow Turbulence
The Vane Passing Syndrome

[Bancherd]

For light reading on air-water mass transfer potential of stepped cascades, try:

http://www.uq.edu.au/~e2hchans/reprints/jide02_1.pdf

[kingkong]

Quote: Originally Posted by Bancherd For light reading on air-water mass transfer potential of stepped cascades, try: http://www.uq.edu.au/~e2hchans/reprints/jide02_1.pdf

Sounds great but can not open this site with my system. What is the guts of the information Bancherd ?

[Doug Ward]

Bottom line.
Media has surace area to grow nitrifiers.
Nitrifiers grow best with full oxygen saturation, or in the case of the Voodoo Shower, supersaturation.
It will work at a drip trickle, submerged media( well aerated water) or a blasting shower media.

I'll tell a secret. I have BH media running in 2 canister filters doing 150 gallons of aquarium water.
It performs admirably... just like cheap ceramic donutz.
NO. I didnt buy it !

By design. The BS,,, I mean BH media can handle a more violent flow of water than say, a ceramic donut or little green army man or pvc strips or strapping tape or...
Matter of fact its about like Lava rock !.... which is $600 for 18 YARDS.

If you had an airstone in a casket under ground the results would likely be the same.

If you look at REAL water treatment...as in human waste conversion, you'll see a slow rotating, huge spraybar spreading the water which has had the solids removed over far infra... I mean ceramic media as it goes around and around 24/7.
The water then gets pumped back to a tank for bacterial analysis and treated there, as necessary.
The one I'm familiar with is a 300 foot circle with a 300 foot spraybar pivoting from the middle.I'd guess it makes a complete circle in ??? 3 minutes ?
The media is about 4 feet deep.
The pump is a 35 horse electric so I'll take a wild guess at 3500 gpM, which is about what my buddy runs at the striper farm.

They have the place locked up with heavy security so I'm not sure how many Nexuses with answers it takes to remove wastewater solids from 175,000 homes a day, before it reaches their Caca Showwerz.

The bottom line is solids removal before bacterial filtration so most any setup can, and will, work.

Maybe we could get Koiphenator to fill his stream with BH and bypass everything but his drum filters and give it a whirl ? I'll betcha it'll work just fine.

Sorry for the Momo~Blasphemy PBUH..................zzzzzzzzzzz

[PapaBear]

Much thanks to Blancherd for the reference. I'll be doing some serious calculations from that to help with my new stepped waterfall design .
Doug,
Your points are very good and well taken. Solids separation is essential no matter what else you do and the same basic priciples used in large commercial/public utility applications are used by us as well. It is all a matter of scale.
My father operates a similar system in the small town I grew up in as he has been the Superintendant of the Utility District there for nearly 50 years now.
Solids seperation via rotating mechanical skimmer/vortex tank, feeding an air churning digester, which feeds evapotranspiration ponds. The ponds are further aerated by an air induction system of his own design using low head high volume pumps and air drafting nozzles. I'm putting together a scaled down model of the air induction system for posting and feedback at a future date.