Note by moderator: This post was moved from the thread on the Eawag/EOOS grant ( forum.susana.org/forum/categories/106-us...tzerland-and-austria ) into a separate thread.
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Dear Elisabeth,

Sure, you are right. The smell from the urine tank needs to be dealt with as well.
We are currently using a valve very similar to the one you mentioned but is produced by a Swiss company.
But there are a number of manufacturers that produce such valves..
not only in Germany or Switzerland but also in South Africa - thanks for the tip, I didn´t´know addicom.



Greetings,
Bernard

Dear Bernhard,

The photos you are showing are showing the EcoSmellStop (ESS) from Addicom. As far as I know, Addicom (Peter Dahm) developed them first, but I suppose this is difficult to prove one way or another - and is perhaps not of relevance here.

Here is the "see-through" ESS to make it easier to understand how it works (the urine flows through the blue silicon curtains/flaps that stick together when wet but don't stick so tight that the urine couldn't get through):

Eco Smellstop for waterless urinal from Addicom with a see-through cover for demonstration by Sustainable sanitation , on Flickr

More photos are also available here:
www.flickr.com/photos/gtzecosan/sets/721...035/with/3990983118/

There is actually a parallel discussion on the forum about waterless urinals here:
forum.susana.org/forum/categories/34-uri...riences-odour-issues


Regards,
Elisabeth

in the very short time i´m in the uddt "business" now I heard a lot of gossip concerning these patents . I will not comment on this to keep the thread somewhat on topic. PM me if you need help finding the patent documents.

Dear Bernhard, dear Elisabeth and all readers,

currently I am in the process to improve the MoSan (mobile urine-diversion-toilet for household use) - find information about it here:
forum.susana.org/forum/categories/52-mob...an-now-in-kenya#6521 .

I am looking for a smell stop for the urine part that is low-cost and easily adaptable to my design. I already found the Addicom EcoSmellStop, which was discussed here before: forum.susana.org/forum/categories/106-us...and-and-austria#3697

Today I found a similar product by Keramag: "Anti Syphon Trap" ( pro.keramag.com/de/produktdaten/produktd...bank.html?mnr=595710 )

@Bernhard you mentioned similar valves? Even by Swiss manufacturers? Please share with us, where can we find them?

Many thanks in advance!
Mona

Mona wrote: @Bernhard you mentioned similar valves? Even by Swiss manufacturers? Please share with us, where can we find them?

www.enswico.com (eawag is in contact with them as well... ZRH / CH connection)
www.culu.eu (I was in contact with him several times - very helpfull guy)

best
b

ps: let´s talk next week

Dear Mona,

That odour control device by Keramag that you mentioned is in wide-spread use in the Keramag waterless urinals. I would say it is good and reliable. We had the Keramag waterless urinals in the Saniresch project (and they are still installed at the GIZ building now - as they are in thousands of other locations in Germany). Maintenance requirements for these "flat rubber tube" valves have been described in detail in the Saniresch reports (see: www.saniresch.de or in SuSanA library: www.susana.org/library?search=winker ). In short, you need monthly manual cleaning for public facilities (maybe less at household level). This is fast & easy but nevertheless it was a constant struggle for Martina and her team to keep ensuring that the cleaning staff does not "forget" to do it. Hopefully one day it would be routine for them, just like changing empty soap dispensers.

The EcoSmellStop in my opinion is a superior design. It looks similar to the Keramag device but it uses two silicon "curtain" pieces and has certain self-cleansing properties and needs less frequent maintenance and also lasts longer. I can vouch for its long life-time, we have a plastic waterless urinal at home and the same ESS has been in there for so long that I can't even remember when I last changed it. Could be two years by now.

I wrote a paper together with Peter Dahm (the Swiss-South African inventor of the ESS) already back in 2009:
susana.org/lang-en/library/library?view=...peitem&type=2&id=890
von Münch, E., Dahm, P. (2009). Waterless Urinals - A Proposal to Save Water and Recover Urine Nutrients in Africa. 34th WEDC International Conference, Addis Ababa, Ethiopia.

The above-mentioned comparison of the two designs is explained in there.

I also wrote about it together with Martina Winker in the technology review on urine diversion components here:
susana.org/lang-en/library/library?view=...peitem&type=2&id=875
von Münch, E., Winker, M. (2011). Technology review of urine diversion components - Overview on urine diversion components such as waterless urinals, urine diversion toilets, urine storage and reuse systems. Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH. Eschborn, Germany.

OK, so I think the ESS is good, now the next question is: where can you buy one? This is the manufacturer in South Africa: www.addicom.net/ . You told me that you didn't receive a response from them yet. I could imagine that there must be also suppliers in Germany, either with a licence from Addicom or producing something very similar which uses the same principle.

I had a quick look on Google and there is this one for example:
www.watersave-urinalsysteme.de/produkte/zubehoer



(I remember seeing it in real life too)

Oh and the Ernst waterless urinals use the same one as the ESS, too, you can see it here:



www.system-ernst.de/index.php/ernst_urinal_1000.html

They call it the KI valve (I think from Keller Invent).

Unfortunately, there are some nasty patent fights over all this - I somehow know one side of the story, but I think it's prudent if I don't write about it here on the forum.

I have been very impressed with Peter's work in South Africa, so I hope you can either get the ESS from him or he can tell you which company to buy it from in Germany.
Good luck!

If anyone else has more insights and ideas on the EcoSmellStop or similar devices, please let us know.

Regards,
Elisabeth

Dear Elisabeth, dear Bernhard,

thanks so much for your detailed information.
Today I received a price offer from Keramag. The "Anti Syphon Trap" which is used within their waterless urinals costs 30€ + Mwst. (added tax) in Germany.

I hoped it would be less. Maybe the ping-pong ball needs some re-design to become a feasible smell stop solution

Looking forward to talk to you in person Bernhard.

All the best,
Mona

Hi Mona;
talking prices: Talk to Mr. Henniger (he´s German aswell) from Culu.
Nice guy! - Tell him my "Liebe Grüße von Bernhard Ranner / EOOS"

Best
B

Could it be that the 30€ are for a low volume sample? I can hardly believe that such a thing should cost more than 5€ mass produced.

Otherwise... tried the old cut condom trick?

There's always that trade off between cost and quality... I think the ESS costs in the order of 15 Eur, and they need to be manufactured to a high precision with Swiss (!) machines to work with the silicone otherwise it doesn't work properly...

Krischan mentioned the "condom trick". In the interest of those who don't know what he means with that: it's about using a condom that is cut off at the top. See this photo which is also from our great UDDT technology review:

WECF Urinal condom by Sustainable sanitation , on Flickr

My take on the story is that it might work in cold climates (tested in Eastern Europe) but not in hot climates (experiences by Heike Hoffmann and Christoph Platzer in Peru).

This is what we wrote about it in the technology review:
susana.org/lang-en/library?view=ccbktypeitem&type=2&id=874

A simple supplementary odour control measure has been used in Eastern Europe by the NGO WECF on conventional flushing urinals that were retro-fitted for a waterless operation. All but one of the urinal’s drainage holes were sealed and a condom with a small hole cut into the tip was fitted over the outflow piping. This simple setup allows the gravity driven drainage of urine into the discharge piping, but prevents the migration of odours from the urine collection vessel and piping into the UDDT super-structure (see Figure 15). However, practitioners working in warm climates have reported that these condoms fail to work because they stick together within a short time, for example if the toilet is not used for a day.

Christoph Platzer also wrote about it in this thread: forum.susana.org/forum/categories/34-uri...es-odour-issues#3678

At least peruvian condomos were too sticky. they glued together. Who has tried them out as well?
But our experience is...over 400 simple waterless urinals (fiberglass)... you just have to care that the urine flows down, no point at all where it could accumulate. No 90° bending (VERY IMPORTANT, as easily at that point you have "ponding"), strong slope, the proper urine piping is crucial. We had some problems with odour, but ALL related to the mentioned errors.

So our experience is: it is not necessary to have smell stops in cases of individual toilets or a small number of toilets.

Another idea is to use charcoal, I have no first-hand reports on this, other than what we wrote here:

A further option for odour control at the point of the user interface may involve the use of charcoal, which is supposed to have the ability to adsorb urine odours. Charcoal contained in a mesh bag and placed directly in the urine-diverting section of the user interface has been applied in the Philippines, and shown to be an effective means of odour reduction (Gensch et al., 2010). The adsorptive capacity of the charcoal will be gradually exhausted, and the charcoal thus requires regular replacement.

And we also wrote about the idea with the ping pong ball:

It has been suggested that another option to control odour could be a plastic ball (size of a table tennis ball) which is placed in the urine funnel of the urine diversion pan and could act as a one-way valve to prevent back-flow of odours (see Figure 51, right). When a sufficient volume of urine enters the funnel, the ball would float, allowing for the drainage of urine. When the urine has drained completely, the ball would return itself atop the drainage pipe, preventing odour from migrating into the toilet cubicle. The authors doubt that this system could work reliably, and no detailed experiences with this concept have been reported to our knowledge.
A one-way valve consisting of two silicon curtains or a flat rubber tube offers a more sophisticated odour control measure (von Münch and Winker, 2011).

The mentioned Figure 51, right, is this one (here a light bulb was used; I have severe doubts that this could work in the long term and am worried that the light bulb could break):

eco-lilly ethopia by Sustainable sanitation , on Flickr

I am happy to hear from others about their experiences with simple or complex odour control devices for waterless urinals or urine diversion toilets.

Regards,
Elisabeth

Oh and one more thought: Mona, do you have a cut side view drawing of your MoSan toilet? I would like to see how the urine goes from the collection bowl to the canister below.
What I have heard from others is that odour can be minimised if the urine pipe is submerged into your container all the way to say 2 cm from the bottom. This way you reduce the available urine surface area to just the surface area of the pipe.

I think this is how Karsten from SuSan Design in Norway solved the problem for his beautiful uni-sex waterless urinals (which have not yet been mass produced unfortunately) - these photos are from a trial in Kenya which GIZ co-financed (more photos are available in the flickr set, just click on one of them below or here: www.flickr.com/photos/gtzecosan/sets/721...909/with/5196378446/ ):

Girls Urinal 6 - Stones to help younger girls to use the urinal by Sustainable sanitation , on Flickr

A young girl in one of the households that tested the urinal for 2 weeks by Sustainable sanitation , on Flickr

Assembling 4 SuSan Design by Sustainable sanitation , on Flickr

Regards,
Elisabeth

Dear Mona, and others,

Looking at the pictures above, I was just wondering whether using a piece of bicycle tube would be a way to make a more durable solution then the condom trick? Has anyone tried this?

rgds

Marijn