SuSanA - Forum Kunena Site Syndication Sat, 29 Aug 2015 12:37:12 +0000 Kunena 1.6 SuSanA - Forum en-gb Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundacion In Terris, Ecuador) - by: muench 1-page summary about the current status of this project in a recent report by the BMGF called "Building Demand for Sanitation - A 2015 Portfolio Update and Overview" (available here in the SuSanA library; I will make another post about this report soon)

From this pdf file:


Accomplishments to Date:

• 86 demonstration Earth Augers installed; over 50 additional
installations expected in first quarter of 2015.
• Arrangements for micro-financing household toilet purchases
should reduce cost for the user to $225-$565 (with the higher
amount including the superstructure), paid back at $10-$24
per month over a 2-year repayment period (equivalent to a
cost of $0.07 to $0.17 per user per day for a family of five).
• Several State & County Governments are interested in
the toilet; approval for the design by National Ministry of

Key Learnings to Date:
Early products, which were partly hand-built, had reliability and
user acceptance issues and a relatively high cost. Project targets
were adjusted to provide more time for design improvements
and collect in-depth performance data and user feedback. The
business plan is currently under development, and the project
has been extended until end of 2015. Commercialization goals
are focused on the Ecuadorian market.

Lessons learnt:

• The discovery that it is possible to have plastic components
manufactured without paying the full cost for a mold (but
instead paying mold “rental charges” to the manufacturer)
transformed manufacturing options allowing the project to
stop using the low-quality hand built components.

• Testing early products at small scale and collecting user
feedback is necessary before scaling up production.

• Business models need to be based on local field data. In the
absence of reliable data, crafting a sound business plan takes
significant investment of time, effort and resources.

Next Steps:
Further efficiencies will be sought along the supply chain
to ensure sustainability, along with finding additional ways
to reduce the unit’s retail cost. As the demonstration model
moves towards production, FIT will increasingly focus on
building demand for the units by increasing the product’s
aspirational features as well as further cost reductions. FIT will
use crowdsourcing to speed up development of solutions and
identify design and manufacturing improvements. From a user
protection perspective, FIT will be seeking improved methods
for increasing (and measuring) pathogen die-off during the
composting process, and to ensure the safety of land application
of mature compost products. FIT also will collect data regarding
users’ experience including the toilet itself, as well as any
benefits gained from composting.


I thought this could be interesting for those following the progress of this project.

User interface technology innovations Fri, 28 Aug 2015 16:33:04 +0000
Re: Industrial Ultrasound in redesigned toilet seat - by: dineshbr User interface technology innovations Wed, 26 Aug 2015 05:20:48 +0000 Re: Blue Diversion AUTARKY - A self-sustaining toilet off the grid (EAWAG, Switzerland) - by: SteffiE
thank you very much for your critical comments, we really welcome them.

It is true that the Autarky toilet requires constant electricity, but this energy demand will be covered by a solar panel. To switch the toilet on or respectively heating up the feces module, a generator or a plug is needed once. The installation of the toilet must be done by trained stuff which involves the provision of a generator for this first heating up. We consider it more complicated to get energy from outside as you proposed.

Regarding your doubts on the feces treatment, we think it would be a very big step if we could treat feces on household scale and a tremendous cost reduction from an environmental and social point of view. The reactor concept consists of materials which are available in almost all parts of the world and not of high-tech nature, we always have the cost argument in mind (it is difficult but we really do).

We will develop a modular toilet where urine, water and feces should be treated independently but in one toilet system and thereby being able to respond to different demands and conditions. It might be an option that urine is distributed to the soil in less populated areas, however it is not the safest way and in this project we have the goal to develop a toilet especially for the urban context where no space is available to do so.

I hope I could answer your questions - if not, please let me know.
Thanks a lot for your comments,
User interface technology innovations Tue, 25 Aug 2015 14:30:47 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: shraysaxena88
Thank you for your question.
We currently have a ventilation pipe for the toilets to reduce odors from spreading inside the house. We 'guess' that it increases the drying rates however small that may be. Further laboratory testing is under way to quantify this amount.
Our next phase of testing is a change in design from a large 55-gallon drum to a smaller 10.5 gallon drum size. This allows for a higher volume to surface area ratio. But as shown in my presentation that Elisabeth has posted, the drying rate is dependent a lot more on the ambient temperature and humidity conditions.
The drying rates are slow for a over-populated nation of washers but it should work well for drier and hotter climates where water stress is an issue.

Shray Saxena]]>
User interface technology innovations Tue, 18 Aug 2015 14:06:24 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: JKMakowka
On topic: have there been further trials if increasing the aeration around the membrane, or a different membrane arrangement that does not allow a big 'clump' of feces (with a low volume to surface area ratio) to form?
The idea is very good, but it's a pity that the current data seems to not show such a great increase in drying rates.]]>
User interface technology innovations Sat, 15 Aug 2015 01:56:31 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: shraysaxena88
I just wanted to update about the field application of the breathable membrane toilets. We have a total of two toilets in two households in Kanpur, India which are in active use. We are still learning about the effect of different weather conditions on the membrane drying rates (drying time).
A good summary of the field work till date has been documented by our collaborators, WaterAid India, here -

Please feel free to revert any questions/concerns about the toilets and its technology on this post. I will be happy to answer them.

Shray Saxena]]>
User interface technology innovations Fri, 14 Aug 2015 15:29:13 +0000
Re: Practical and technical questions on use and installation of SaTo pan - by: nicolag
We've been wondering about 'productising' latrine superstructures, but I've been warned that the cost all at once is a bit much...hence we take the approach where we sell the BoQ, not the finished product. This allows people time to gather then money to purchase, and then we produce on site. I would love to have some fixed bamboo frames as you do though and sell it as a product.

User interface technology innovations Fri, 14 Aug 2015 06:51:55 +0000
Re: Practical and technical questions on use and installation of SaTo pan - by: nicolag
Our other big learning point has been about the amount of money that must be spent on marketing. Naively, we underestimated the manpower/marketing required to bring a new product to market.

We find that purchasers in Malawi are drawn in by the cleanliness aspect of the technology, and after a few months of use, cite the reduction in flies as the primary benefit. I'm attaching our marketing flyer in English. Sanitation Solutions in Uganda have also produced nice marketing materials and revised installation guides.

The primary marketing issue is that is so new that it's pretty hard to explain on paper what it is....however, walking around town with one draws a lot of attention!]]>
User interface technology innovations Fri, 14 Aug 2015 06:49:02 +0000
Re: Practical and technical questions on use and installation of SaTo pan - by: JKMakowka User interface technology innovations Mon, 10 Aug 2015 02:57:49 +0000 Re: Practical and technical questions on use and installation of SaTo pan - by: muench That's a great idea, thanks for starting this new thread.
The SaTo pan seems to be pretty popular in Uganda, see e.g. the post by Sherina Munyana here. She wrote:

The SaTo pan has proven to be a really popular product for latrine improvement - both in terms of affordability and the benefits of making a latrine more hygienic, free from flies and safe for children. Since October 2014, SSG has sold over 2700 pans. SSG is identifying strategic partners through whom to distribute the pans both in the rural and urban areas which will help to achieve wider scale and impact.

More information about all our products and services can be found on our website

I also had a chat with Lillian Nabasirye from Uganda at the recent WEDC conference about the SaTo pan. She said she was surprised at how popular they have become with rural people. I have just sent Lillian an e-mail and encouraged her to describe her experiences here on the forum.

I thought that the flap might get soiled quite badly with faeces quite quickly but apparently not so. Either because it is so light that it flaps back at the slightest of weight being added on it. Or because the flushing with water afterwards really helps to keep it clean? (mind you, I would expect that a brush would be needed, too?) Or because the surface is completely non-stick (and some water remains on the flap even when it's closed?)?

Does anyone have photos or videos of a SaTo pan after 12 months of use? What if the users don't use any flushing water with it? How long is it meant to last before a replacement is neeed?

User interface technology innovations Sun, 09 Aug 2015 20:56:57 +0000
Re: Sanitation Product Development for Sub-Saharan Africa - affordable, aspirational latrine products, SaTo (American Standard Brands, USA and Water for People) - by: Alfonso
I also take advantage to update Jim: The contact has been very successful. Thank you very much for your support on this issue. We will keep in touch.

Best regards,

User interface technology innovations Sun, 09 Aug 2015 10:58:54 +0000
Re: Sanitation Product Development for Sub-Saharan Africa - affordable, aspirational latrine products, SaTo (American Standard Brands, USA and Water for People) - by: Arjen
I have been looking for a location to discuss the technical and share practical experiences of the SatoPan. I felt that this topic thread is a bit broader and therefore I have opened a new topic, click here:
"Practical and technical questions on use and installation of SaTo pan".

I hope you will be able to contribute to that thread as well!

thank you,

Arjen Naafs
Regional Technical Advisor WaterAir South Asia]]>
User interface technology innovations Fri, 07 Aug 2015 09:26:26 +0000
Practical and technical questions on use and installation of SaTo pan - by: Arjen
The Sato Pan is being rolled out in many countries and we are all getting experiences in using them. However, I have been missing a forum/topic to discuss practical and technical tips on installing the SaTo pan.* Therefore, I have opened this topic and would like to start by looking for answers for the following:

1) Any experiences to make the slab using any other material than cement (planks?)

2) Can an off-set pit be used with SatoPan? Any experiences with this?

3) Has anybody tried to install them in smaller square slabs produced?

For your information, WaterAid has made a video on how to install a SaTo pan, but we still are looking for answers of the above.

Feel free to add your own questions, share technical manuals and provide answers!

Thank you,

Arjen Naafs
South Asia Regional Technical Advisor WaterAid


* Note by moderator: Another thread about the SaTo pan (describing some funding by the Gates Foundation) is available here:
and here in Uganda:]]>
User interface technology innovations Fri, 07 Aug 2015 09:21:50 +0000
Re: Blue Diversion AUTARKY - A self-sustaining toilet off the grid (EAWAG, Switzerland) - by: canaday
Thank you for this info. I am disappointed that this model constantly requires electricity, as this limits its decentralized application. And what happens when there are blackouts?

I suggest it may be worthwhile to explore the possibility of getting energy from exercise or playground equipment on the outside of the toilet.

This new model takes on the huge challenge of processing all of the excrement on-site, but this seems to be with expensive, high-tech equipment that may be prone to failure and more complicated to maintain. (And the more expensive it is, the more likely it may be stolen to sell intact or in its component parts.)

I suggest that you offer the option of simply distributing the urine in the soil among fruit trees or urban agriculture, via a perforated hose buried below the surface (in places where there is enough room). Also, in places that are not so water-stressed, new water could be piped in and then also be dispersed in the soil.

In general, I think it would be good to keep various options open in order to adapt to different conditions, remembering that not everyone who needs a toilet is in the inner city (with electricity).

In any case, it will be spectacular if you achieve reliable, economical on-site treatment of the feces, in such a small space, since the feces are obviouosly the most dangerous portion of the excrement.

I look forward to seeing more details and news from your project.

Best wishes,
Chris Canaday]]>
User interface technology innovations Tue, 04 Aug 2015 01:49:18 +0000
Re: Blue Diversion AUTARKY - A self-sustaining toilet off the grid (EAWAG, Switzerland) - by: SteffiE
We would like to update you with further insights on the different modules of the AUTARKY-project, namely the urine, water and feces treatment in our toilet. As mentioned in the project description, we separate the three streams and treat them on-site, even the feces!

Urine treatment

Two processes are necessary to treat the source-separated urine in the AUTARKY toilet: urine stabilization and water removal. Stabilization is necessary to avoid malodour which occurs during storage, to inactivate pathogens and to conserve the valuable nutrient urea. Once the urine is stabilized the volume of the urine will be reduced by evaporation, the remaining end-product is a mix of salts. After further external treatment steps these salts can be used as fertilizer in agriculture.

Urine stabilization in detail
The main goal of this treatment step is to prevent urea hydrolysis, which is a process that converts urea to ammonia and carbon dioxide. Through the addition of calcium hydroxide to fresh urine the pH increases to values above 12 and prevents microbial urea hydrolysis. An additional benefit of the high pH value is the killing of pathogens and the prevention of biological processes that produce malodour.
When Ca(OH)2 is added to the urine only about the amount dissolves, which is needed to reach the necessary high pH value. This allows providing a depot of Ca(OH)2 in the stabilization tank; therefore no expensive and complicated dosage mechanisms are required. Moreover, calcium hydroxide is a cheap reagent and readily available worldwide. An additional benefit of Ca(OH)2 dosage is the precipitation of calcium phosphate. This mineral could be recovered apart from the other urine compounds and used for fertilizer production.

Urine water removal in detail
The direct application of human urine as fertilizer is a common practice in many rural areas worldwide. However, the high water content of urine – no matter if stabilized or not – requires significant storage capacity and can make the transport to the agricultural fields very costly. Volume reduction does not only reduce costs for storage and transport but could also facilitate field application of the concentrated fertilizer. Standard volume reduction techniques are most often energy intensive processes, because they require high temperatures (distillation) or pressures (reverse osmosis). We are currently focusing on several evaporation techniques, which do not require any heating and pressurizing processes. One example is the evaporation pipe where urine is trickled down a pipe, which is aerated with ambient air that takes up water. Our goal is to recover a hygienically safe end-product that concentrates valuable nutrients that will be applied to cropland.

Water treatment
The preceding project Blue Diversion, achieved tremendous progress towards developing gravity driven membrane technology (GDM) into a practical toilet water recycling system for urban developing world applications ( The goal of AUTARKY is to better understand and verify the safety of our system with respect to the user and to explore alternative technologies which may reduce capital and energy costs. We are also examining how the same membrane technology functions in systems representing higher and lower organic and nutrient loading. The gravity driven membrane achieves approximately 95% removal of organic carbon entering the system. Additional treatment is required to maintain microbial stability within the clean water tank. Microbial stability refers here to water with limited potential for contamination and growth of pathogens. The electrolysis unit in the previous version of the toilet has demonstrated an ability to reduce organic carbon concentrations and produce a chlorine residual, both of which help to limit pathogen growth.

Treatment technologies such as activated carbon, ozone and UV light are being considered as alternatives to the electrolysis. These alternatives may be less expensive to install and maintain, and they may produce superior water quality given considerations such as their impact on biology of the membrane. The advantages and disadvantages of each technology will be first evaluated in batch; promising technologies will then be integrated into full-scale toilet systems. A quantitative microbial risk assessment will be performed on the entire module. In this regard, pathogen surrogates are used to investigate passage through the membrane and in competitive experiments with the natural bacteria community which forms in the clean water reservoir.

Feces treatment
In the Autarky toilet, feces are separated from urine and collected in a container at the bottom of the toilet. They may contain harmful compounds such as pathogens and must be inactivated quickly to avoid anaerobic decomposition and the emission of malodorous gases. In our approach the organic matter of the feces sludge is completely mineralized to carbon dioxide, water and minerals such as phosphate salts. The remaining streams are off-gas and a mixture of water and minerals. The off-gas contains mainly nitrogen, carbon dioxide and oxygen and can be safely vented to the atmosphere. The aqueous stream may be utilized as a fertilizer.

Feces mineralization in detail
When mixed with air and heated above ca. 400°C under high pressure, the feces sludge decomposes and is oxidized completely to carbon dioxide and water. This process is called “hydrothermal oxidation” or HTO. The water in the sludge does not evaporate but mixes with the air and provides a reaction environment for an efficient conversion of the organic matter within a few minutes. We are developing a comprehensive computer model of the HTO reactor to be built for the Autarky toilet. This computer model is fed with data from experiments carried out in small autoclaves with real fecal sludge. We determined that the oxidation reaction is rapid above ca. 300°C and runs to completion within a few minutes at 400°C. The next step is to build a small laboratory-scale prototype to perform experiments under more realistic conditions and to test the model predictions. With the validated model a full-scale prototype will be designed and built in 2016.

We are happy to answer your questions or give you more detailed information,
User interface technology innovations Mon, 03 Aug 2015 12:18:00 +0000