SuSanA - Forum Kunena Site Syndication Tue, 30 Sep 2014 19:52:39 +0000 Kunena 1.6 SuSanA - Forum en-gb Re: The Nano Membrane Toilet (Cranfield University, UK) - by: AParker
In our latest conversations with BMGF they really liked our small footprint aspirational concept:

But they didn't like our plan to collect the solids weekly. So they suggested we pair with another grantee who could help us process the solids in the toilet, hence the link to RTI. With onsite solids processing there's no need for the coating so we're not taking this any further. We'll need to work hard to keep is both safe and cheap. It will operate as a batch process. So we'll automate it to operate when it's not being used. And we're going to gauge responses from households in Ghana about how they feel about having such a unit in their homes, as well as feedback from, RTI's ongoing field trial in India:

Hope that answers your question, do keep asking them!

Processing technologies for excreta or faecal sludge Mon, 22 Sep 2014 13:53:30 +0000
Re: The Nano Membrane Toilet (Cranfield University, UK) - by: muench
Congratulations on receiving this next phase of funding! That's great news for you and your team!

Can you tell us the size of this new grant (it is not yet visible in the BMGF grant database)?

And I read on your blog:
The biggest change is that rather than coating the dried solids, we're now looking to combust them in the toilet using a gasifier - we'll be working with RTI * who are already testing their gasifier in India. This changes the energy balance of the toilet, for example we can now consider recovering the water using a heat exchanger instead of the beads, and we won't have to use the bicycle power generator or hand crank to power the membrane processes.

* The RTI project is described here on the forum:

Could you tell us a bit more why you abandoned the coating and bead ideas?
And are you going to try and embed the gasifier in your small toilet model? I would find that a bit scary to be sitting on something that operates at high heat and with combustion... Would a unit like that really make sense at household level with all the associated safety issues? And wouldn't it increase the costs a lot?

Processing technologies for excreta or faecal sludge Mon, 22 Sep 2014 12:33:15 +0000
Re: The Nano Membrane Toilet (Cranfield University, UK) - by: AParker [Start of Page 4 of the discussion]

We are delighted to announce that the Nano Membrane Toilet has received further funding from the Bill and Melinda Gates Foundation to continue the development of the toilet. This next phase will take us to January 2016 when we will have a prototype ready for field testing. We're really excited to be starting work again after a 6 month break.

Read more about our plans on our blog:

As ever, happy to answer your questions and receive your feedback on this forum.]]>
Processing technologies for excreta or faecal sludge Fri, 19 Sep 2014 15:35:48 +0000
Re: Self Sustained eToilet for households/ Urban-semi urban Public/ Community Sanitation (Eram Scientific, India) - by: Bincy Self-Sustainable Sanitation Model through eShops “India’s First Technology-Enabled Shops

Eram Scientific Solutions (ESS) has launched “eShop, India’s First Technology-Enabled shop in Kozhikode, the third largest city in Kerala earlier this month. eShop, the first-of-its-kind self-sustainable entrepreneur model is a developmental initiative taken towards empowering the BoP segment of the society.

Having established a network of more than 500 eToilets spanning across 10 major States PAN India, this unique entrepreneurial eShop Model will promote sustainable community sanitation technologies through eToilets and simultaneously open up a new livelihood source for communities through eShop. The eToilet-eShop Model will ensure revenue generation and sustainability ensuring entrepreneurship promotion initiative across India. The eShops are implemented in close proximity with the existing eToilet units to promote responsible sanitation hygiene practices amongst the common man.

The eShop would provide entrepreneurs with multiple sources of income through sale of goods, income generated through user charges and advertisement revenue from eToilet. This would function as a value-added service along with the eToilet and would facilitate employment as well as income generation for the entrepreneur. Moreover, it would result in improving the maintenance mechanism of eToilet since the entrepreneur of the eShop would also be responsible for ensuring proper maintenance and cleaning of the eToilet and its surroundings.

Considering the huge unemployment rates in India, this unique intervention could trigger mass employment opportunities for small-time entrepreneurs especially women, at large and these entrepreneurs can be engaged to be the Sanitation Champions of the areas.

ESS will be implementing 16 such new-age micro retailing eShop outlets in association with the Kudumbasree Community Development Society under the Kozhikode Corporation in other prominent locations within the Kozhikode Corporation limits. eShops has been opened at five prominent spots in the region as part of the first phase.

ESS is collaborating with iconic brands such as Britannia, Idea, Café Coffee Day, Parle to inspire a nationwide movement taken towards transforming the lives of the BoP segment of the society, especially the women populace with the launch of eShop, a stand-alone initiative dedicated to helping promote livelihood opportunities for the marginal sections of the society.

The potential of this initiative at the next phase is to integrate the proven technologies of solid waste treatment, waste water treatment systems to develop self-sustained urban communities. The recycling potential of energy, water and nutrients from waste treatment can support such communities to meet their utility requirements. Developing micro-entrepreneurship in sanitation, waste treatment and similar sectors would unveil multiple livelihood options for the urban poor. Moreover, the eToilet-eShop locations will be transformed to wi-fi Hotspots to enhance convenience and mobility for the end users.]]>
Processing technologies for excreta or faecal sludge Thu, 26 Jun 2014 07:37:56 +0000
Re: The Nano Membrane Toilet (Cranfield University, UK) - by: AParker
The exhibition is open to the public so anyone can come to visit, but I appreciate that the average Londoner probably isn't our target user! BMGF don't want us to do full scale field trials yet, but we hope to gain a lot more user perspectives in our next phase of work. I can't publish our full plans yet as they are still under discussion but I'll keep you updated. If there's any aspect you think we should be specifically seeking user feedback on I'd welcome your input.

Processing technologies for excreta or faecal sludge Fri, 30 May 2014 10:26:58 +0000
Re: The Nano Membrane Toilet (Cranfield University, UK) - by: canaday
Congrats on this event. It is great to get the word out.

You say "We’ll have all our prototypes so plenty of chance to try them out" and then you say "And you can even sit on our toilet!", which seem to contradict each other a bit. Optimally, all the users who like should be able to use the toilet and see what the user experience is like. Any chance of that?

Good luck with the exhibition,
Chris Canaday]]>
Processing technologies for excreta or faecal sludge Fri, 30 May 2014 10:20:21 +0000
Re: The Nano Membrane Toilet (Cranfield University, UK) - by: AParker
Researchers from Cranfield University will join teams from 44 other UK universities represented at the Museum during the week. The exhibition will include research stations, pop-up performances, debates and live research demonstrations, covering a range of research themes.

The exhibition will be open every day from 10am to 6pm, with late night opening until 10pm on Wednesday 11 June. Cranfield’s Nano Membrane Toilet exhibit will be part of the ‘Environment and Sustainability’ theme and will be based in the Atrium. We’ll have all our prototypes so plenty of chance to try them out. You can see how much power you can generate with our hand crank generator. You can try our waterless flush. You can see our hydrophobic and hydrophilic coatings in action. And you can even sit on our toilet!

There’s a full list of all the events happening for Universities week here:]]>
Processing technologies for excreta or faecal sludge Thu, 29 May 2014 13:30:32 +0000
Re: Sustainable Decentralized Wastewater Management in Developing Countries (AIT, Thailand) - by: muench
Photos of the exhibit and three photos of posters on display are available here in this Flickr album:

Two example photos from this Flickr album:

Solar septic tank prototype by Sustainable sanitation, on Flickr

Hydroclone toilet prototype (the hydrocyclone is on the left, the toilet squatting pan is on the right) by Sustainable sanitation, on Flickr

Information taken from the Technical Guides of the fair (p. 11, see here:;type=2&id=2001)

Solar Septic Tank and Hydrocyclone Toilet

Asian Institute of Technology (AIT) is working on two new
technology advancements in their quest to resolve some
of the world’s sanitation needs. First, AIT is developing
a modification of conventional septic tank technology by
establishing thermophilic anaerobic conditions within
the Solar Septic Tank. The thermophilic conditions,
which primarily consist of applying high temperature
(50-60°C) to septic waste, will offer faster degradation
rates and greater disinfection efficiencies compared
to conventional septic tanks. The system consists of
two main components: a top-floor standard flush toilet
system, and a lower-level solar septic system. The
thermal reactor will be heated through heat exchange
device by circulating hot water surrounding the reactor.
This water is itself heated by use of a solar panel, so no
external electrical source is required.

Additionally, AIT is presenting a black water separator
toilet called the Hydrocyclone Toilet. The application of
a solid-liquid separator is a common unit of operation
in many other fields. However, in the case of onsite
sanitation systems its application is limited and
challenging due to the unpleasant characteristics of fecal
materials. In this regard, AIT is endeavoring to develop
an efficient separator and appropriate onsite solid and
liquid disinfection technology. The Hydrocyclone offers
several desirable characteristics, including no energy
and low maintenance requirements.

Separated solids will be treated primarily by heat
application. By a certain degree of temperature and
duration of exposure, the separated solids will be
disinfected and released from the heating unit. Heat will
be produced by solar energy. The separated liquid will be
further disinfected by using electrochemical technology.
The appropriate conditions and specific configuration of
the treatment technology are being investigated.

Thy hydrocyclone concept for solids-liquid separation looks quite appealing, however I fear that in practice it could quickly get blocked with things that people flush down the toilet (like pads, paper, condoms). Unless these households will all be very diligent? Have you actually tried it out in real life yet, Thammarat?


P.S. Christoph (Platzer), have you been on your mentioned trip to Thailand yet? We hear relatively little about sanitation from Thailand even though I am sure that lots of good work is going on there. As child mortality is low in Thailand (only 15 per 1000 live births which is very good), they must be doing quite well with their sanitation efforts. Check out their remarkable journey in reducing child mortality rates in Thailand in recent decades! :

Processing technologies for excreta or faecal sludge Tue, 20 May 2014 13:28:10 +0000
Re: Sol-Char Toilet: Using Concentrated Solar Energy to Treat Fecal Waste and Produce a Valuable Soil Amendment (Uni Colorado, USA) - by: richardpfisher real human feces collected on campus from donors, not from waste water sludge or pit latrines. We had several poo donation drives at the Engineering building on campus and students were generous with their donations .

About our RTT project:
Unfortunately, we will not be moving forward with our own Reinvent the Toilet Challenge prototype. The foundation has encouraged us to consult with other RTT teams that wish to incorporate high temperature concentrated solar power into their prototypes. Through September 2014, we will be continuing on with our research efforts as the project wraps up. So there are going to be several publications coming out on topics ranging from solar physics to biochar characterization. It'll be exciting work in the coming months!

So to address your comment about achieving the Reinvent the Toilet Challenge goals in 16-24 months:
Since we won't be developing another prototype, we probably won't have the opportunity to develop our technology at lower cost. But we had envisioned the next prototype including a pre-drying step using "lower-grade" heat from a small parabolic trough then using a small parabolic dish to quickly pyrolyze the pre-dried waste. This unit would have served on the order of 50 people per sunny day and used less expensive concentrating solar components, e.g. sans fiber optics, and included waste storage for weather events such as week-long overcast. This unit would have met the foundation's user cost target ($0.05/person/day) for an estimated capital cost of about $10,000-11,000. There's a lot of assumptions embedded in that estimate that I'll save for another post.

To answer your questions about climatic factors such as hail:
Later on this summer, we will hopefully test our reactor and fibers under prolonged weather exposure in order to assess their performance degradation over time. In typical CSP plants for electricity generation, there can be significant O&M but one must keep in mind that those plants have km^2 areas of mirrors – so small inefficiencies translate to major reductions in the total power production. Luckily, our system has about 2m^2 of mirror area, so with our relatively small system we have not been as concerned about minor efficiency losses due to a dirty or dusty mirror surface.

Hail damage could cause problems but I suspect they would have to be large diameter hail; the mirror substrate is solid aluminum, no less than 10mm thick at any point. The reflective surface itself was designed by 3M (famous for Scotch tape) for deployment into harsh environments, such as the US desert southwest, where high winds and sand/dust storms are common. The small turning mirror surfaces are more delicate but it’s not hard to envision a robust housing for weather protection, which came in as a low-risk of failure in our analyses. It would be really neat to see what kind of impact a hail storm would have on our mirrors though because Colorado summers see many hail storms each year.

We didn't spend time on any of the above failure mechanisms because, frankly, we had more catastrophic failure modes with which to concern ourselves. Up until last summer, we melted every fiber bundle that we could get our hands on -- keep in mind that these fibers are borosilicate glass with an initial melting temperature of about 700 degC. We were definitely in peril of not demonstrating even a proof-of-concept so field-readiness and prototype cost took a backseat as a result of the technical challenges we faced. It's not that fibers are delicate or fickle, it's more that only three firms in the US (or world from what we can tell) actually make fused glass optical fiber and they're not easy to find. So we have operated in an empty space, on the lunatic fringe as we affectionately call it, because of our unique technology and application.

Thanks, again! We’ll keep posting updates from any research we are able to perform and collaborations that materialize throughout the summer.

Chip Fisher
Senior Professional Research Assistant
Sol-Char Sanitation]]>
Processing technologies for excreta or faecal sludge Thu, 15 May 2014 23:05:37 +0000
Re: Effective Sewage Sanitation with Low CO2 Footprint (Duke University in Durham, North Carolina, USA) - by: AquaVerde
I am unfamiliar with the abbreviation "CHP." What does that stand for?

sorry for being very late:

Cogeneration or combined heat and power (CHP) is the use of a heat engine[1] or power station to simultaneously generate electricity and useful heat.

All the Best
Processing technologies for excreta or faecal sludge Sat, 10 May 2014 14:15:25 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: skdentel The membrane we used is also defined as oleophobic, so I don't believe oil is penetrating into the membrane. There is some research suggesting that nonpolar functional groups on proteins are the culprits.]]> Processing technologies for excreta or faecal sludge Fri, 09 May 2014 11:56:18 +0000 Re: Sustainable Sanitation Alliance Interviews Brian Stoner from RTI International - by: muench

Quite a few of the other grantees mentioned a collaboration (planned or already in place) with RTI on their electrochemical disinfection technology for liquid waste.

Some example photos from the album:

Entrance to the toilet part of the WiC. The blue section to the right also contains some of the drying and combustion components. by Sustainable sanitation, on Flickr

Liquid treatment components contained under the toilet platform. by Sustainable sanitation, on Flickr

Electrochemical disinfection unit for treatment of liquid waste by Sustainable sanitation, on Flickr

Demonstration of the flush by Sustainable sanitation, on Flickr

Solid waste is transported and dried using a screw-like device up and to the left through the metal section. by Sustainable sanitation, on Flickr]]>
Processing technologies for excreta or faecal sludge Fri, 09 May 2014 08:59:29 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: JKMakowka
Otherwise: anaerobic septic sludge really isn't the best substitute for fresh feces. My guess is that the higher oil and fat content of fresh feces is what is causing you trouble.]]>
Processing technologies for excreta or faecal sludge Fri, 09 May 2014 05:29:39 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: skdentel Yes, the "breathable membrane" has been promoted to Phase 2. We are very excited about this. Of course we have a lot of work to do!

To tell the truth, reviewers have been pretty skeptical of our work. It is hard to believe that the membrane does not clog when fecal sludge is right up against it. It has been surprising for us too.

We started out using anaerobically digested wastewater sludge as a very reproducible substitute. We also collected sludge from a camping site outhouse. In neither case was there a decrease in drying rate as drying occurred (except, of course, when the moisture is almost gone). Drying to completion, shaking out the dried material, and rinsing, we then repeated the experiment with the used fabric, up to five times, with no loss in drying rate. So the fabric acts like a non-stick surface, perfectly, and there was no sign of clogging.

More recently we have been using fecal sludge which we have to obtain from student volunteers (I'll skip the anecdotes here!). And it turns out that true fecal sludge is a bit stickier than the other sludges we were using (other researchers using soy paste and other substitutes should be alerted to this!). yes, the rate of moisture penetration through the membrane fabric does slow as drying progresses.

We were pretty dismayed by this, but repeated tests have now shown that (1) the rate is still pretty fast for the initial drying phase, which is the most important, and (2) the drying behavior does not deteriorate when the fabric is rinsed and re-used - it's pretty much the same as in previous cycles. So the news is not so bad after all.

So now, our research will now go in two directions. The first is a scientific inquiry into what's different about fecal sludge, using a variety of sophisticated analyses, so we can try to decrease its importance.

The second is more practical. Our calculations show that the membrane enclosure should be very suitable for certain applications, and the most obvious is where the fecal waste is contained above ground level so there can be plenty of surface area for drying. So picture this: the toilet, with u-trap, mounted onto a surplus 200-L drum with perforated walls. The fabric is made into a cylindrical, water-tight "bag" that fits into the drum and seals onto the u-trap at the top. We'll need a spacer between the bag and the drum for air flow and to protect the fabric from any sharp edges. Practically speaking, steps and rails, a privacy barrier, and so forth are needed too.

This is the working plan for our first generation model. It's obviously intended to be simple and low cost, while letting the fecal sludge lose water but keep everything else contained for later composting or other use. We're talking with apparel manufacturers about fabricating the bags to be water-tight, and we will be testing them with Wateraid in Kanpur and elsewhere. WaterAid suggests two drums, on roller wheels, so one can continue drying when the other is being used. Sounds good, although it doubles the cost.

While we learn how these units perform, we'll be working on designs for pit latrines and other systems. These are more challenging because we need ways for air to circulate around the fabric exterior to carry away the moisture. We've got some ideas on how this can be done. Phase 2 will be exciting!]]>
Processing technologies for excreta or faecal sludge Fri, 09 May 2014 03:56:37 +0000
Re: Breathable membrane enclosures for fecal sludge stabilization (University of Delaware, USA) - by: skdentel The breathable membrane fabric could be used on the bottom as well, and no treatment should be needed, because none of the sludge constituents get through the fabric. Only water vapor and other gases.
The fabric facing upward would need to be UV-resistant; some fabrics are available of this type.]]>
Processing technologies for excreta or faecal sludge Fri, 09 May 2014 03:15:23 +0000