Here is an update about a project that I am leading at the University of Toronto with funding from the Gates Foundation. This is Phase 4 of the project. We have been going for 7 years now: Phase 1 started in 2011.

Title of grant: An Integrated Household Scale Sanitation Appliance



(This photo is from the STeP website, it shows me with BMGF project officer Doulay Koné, explaining our technology)

- Name of lead organization: University of Toronto
- Primary contact at lead organization: Stephen Sauder, Project Manager
- Grantee location: Toronto, Ontario, Canada
- Developing country where the research is being or will be tested: India
- Start and end date: April 1, 2018 to June 30, 2019
- Grant type: Reinvent the Toilet Challenge
- Grant size: USD 2,000,000

Short description of the project:

Building on progress made to date for an energy efficient, cyclic-continuous household sanitation process based on liquid/solid separation or dewatering, in situ drying, smoldering and post smoldering catalytic conversion of solid excreta, and heat pasteurization of liquid waste, work during this phase will focus on continuing process simplification, improving reactor thermal performance, reducing mechanical complexity, improving robustness, learning about and addressing user behavior, identifying and engaging manufacturing and commercialization partners, and incorporating their input to reduce cost and productize our technology.

Goal: The goal is a commercially viable sanitation appliance that will be ready for commercial production development.

Objectives: This grant will be used to continue the development of an integrated household scale sanitation appliance – towards multiple site field studies and towards commercialization.

Research or implementation partners: STeP (stepsforsanitation.org/) and Sankoya
(STeP helps partners of the Gates Foundation by streamlining and removing the risk of technology development and commercialization.)

Links, further readings – results to date: N/A
The project's entry in the SuSanA project database is here: www.susana.org/en/knowledge-hub/projects/database/details/551
Or Phase 1 to 3 of this project is here: www.susana.org/en/knowledge-hub/projects/database/details/61

Current state of affairs: Field testing of the fourth integrated prototype will begin October 2018 in Coimbatore, India

Biggest successes so far: Achieving smoldering of full moisture content human feces with no pre-drying requirement, and at controllable rates.

Main challenges / frustration: Mechanical complexity is the main challenge, but we have significantly simplified our system already and will continue to further simplify.

Regards,
Yu-Ling


Yu-Ling Cheng
Distinguished Professor of Global Engineering
Professor, Departmental of Chemical Engineering and Applied Chemistry
University of Toronto
416-978-5500

Hi Everyone,
My apologies for not posting an update sooner. We are fevershily working under the third phase of our RTTC grant. Please listen to Prof. Yu-Ling Cheng's high level presentation at FSM3 in March of this year for a very excellent overview of where we are at.

The exact starting point is here:


Or go to 48m21s here:



We have an integrated prototype that is operational in our lab. We will be testing it using donated human samples this summer. I've attached a photo of our phase 2 prototype. The key differences of phase 2 vs phase 3 is that our phase 3 prototype will be much smaller and will be able to operate without a dedicated daily operator. No photos of our phase 3 prototype yet but will update when we can.

Thanks,

Steve

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Note by moderator:
The presentation slides from Yu-Ling Cheng's presentation at FSM3 are here:
www.susana.org/images/documents/07-cap-d...m-3/3-3-2-4Cheng.pdf
(or on this page: www.susana.org/en/resources/conference-m...ials-2/2015/259-fsm3)

The University of Toronto and its partners at the University of Western Ontario and the University of Queensland are excited to announce that we have been actively working on the third phase of our Reinvent the Toilet Challenge.

We are building on all the exciting progress we made in Phase 2 to make a smaller, more efficient, and cheaper version of our prototype. The technology will not differ much from our Phase 2 prototype. For a very excellent summary of our technology please watch our animated video.

www.bit.ly/sanitationnow


Cheers,

Steve



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Note by moderator (EvM):
See in grant database: www.gatesfoundation.org/How-We-Work/Quic...s/2014/08/OPP1111267
Size: USD 2,349,432

Hi Dorothy,
Thanks again for Following Up - Our project was extended until March 31st. We will be presenting it along with the other RTTC members this March in Delhi. I'll feel more comfortable sharing the pictures and videos of the completed project then.

Thanks for checking in.

Cheers,

Steve

Dear Steve

I wonder if you have any pictures or results to share on your first prototype?
You also stated that end date of the project is 31st of January (see above): is this project now over or any plans to continue?

Dorothee

Hi Dorothy,
Thanks for your question. My apologies it has taken so long to get back to you. It is crunch time for us at 'Sanitation NoW!' (no water no watts no waste).

In regards to the sand / feces mixture we are evaluating a few different mixtures to optimize the process somewhere in between a 1 to 1 and 3 to 1 sand to feces ratio seems to work the best. The ash accumulation is negligible in the process around 4g and we are looking at how to capture this without it turning to dust. The sand gets reused in the system and the ash will get filtered out. There will be a daily process where a member of the household will have to start the sanitation appliance. Also the potential for having a monthly maintenance operation.

We will get delivery of the first integrated prototype in the next few weeks and know more about what will be required then. We'll update the forum in the next few weeks about our project.

Cheers,

Steve

Dear all,

For those of you who are particularly interested in the research project of Yu-Ling Cheng (University of Toronto, Canada), I am giving you below a summary of what was in the expert chat about her project (the expert chat was mentioned here: forum.susana.org/forum/categories/139-ge...te-sept-12-2013#5624)

As a reminder, her project is about:
The Toronto Toilet - Unit operations approach for rapid disinfection of human waste based on drying/smoldering of solid and sand filtration/uv disinfection of liquid waste.

Her presentation starts at 35:45 into the recording, i.e. exactly here:



The question and answer session started at this point in the recording:


Her powerpoint slides are available here:



The first question to her was not recorded properly but I assume it was "what is the sand added for?"?

Yu-Ling's answer: We are talking here about a smoldering process (for example, a burning cigarette is also a smoldering process). We need to get air to the surface of the solid fuel (faeces). The faeces would normally just compress. By mixing with sand we can change the consistency and this helps to get air into the faeces. The sand also acts as a filtering medium as well.

Arno asked: Have you looked at the fate of nitrogen?

Answer: Not yet done. We are focussing on getting enough energy there to pasteurise the faeces.

Tove asked: You mentioned 30 L of liquid - is that in total or for anal cleansing water alone?

Answer: 30 L is the total volume (we are designing based on 2 L of anal cleansing water per day; we have data to show that this is even a conservative estimate). Tove was surprised and said they estimated 2.5 L per day; they are using a normal shower for the anal cleansing in their toilet design)

Bincy asked Yu-Ling and Aaron: "Your toilet is on a raised platform; can you also make it manageable on the ground or under ground?" (meaning that the proessing part would be below ground - the toilet seat itself above ground of course).

Aaron answerd and Yu-Ling agreed on his answer: We are working towards this but it will come only later. It would be good if the toilet processing part could be underground but still accessible and flood proof. For now we want to avoid complications so the entire toilet system is above ground (also needed because it's all gravity flow).

Arno: an above ground toilet has advantages because it can be more flood proof and more resilient.

I hope you found this write-up useful. Please don't hesitate to put further questions or comments here on the forum. I am sure Yu-Ling will be happy to answer you.

Regards,
Elisabeth

Thank you Elisabeth for the write up and thank you Yu-Ling for the participation in the chat!

I actually have another question:
There must be an important volume of sand/faeces/ash mix accumulating in the process? How are you planning to handle this? What will be the frequency of maintenance and what would happen with ash/sand product?

Best regards
Dorothee

Dear Elisabeth,
Yes - finance is a very important aspect for all the BMGF projects. At this point however, we we are focusing on developing our process to work first. After which we will be optimizing to make it as economical as possible.

In regards to your other question - again we aren't sure what the requirements will be. We are building a 10 person scale household toilet and the household will be in charge of maintaining it - the same way we all maintain our own toilets. We are working hard at minimizing user touch points and creating a magic 'button' that would encompass the daily maintenance.

I hope this helps - we should have more to share on our process in the next few weeks.

Cheers,

Steve

Dear Steve,

I had asked a question about the costs for your process, but have now moved that discussion to a separate cost thread, because it applies actually to all the grants; see here:
forum.susana.org/forum/categories/97-ena...luding-capital-costs
(feel free to answer here or there about the costs of your process)

My other question on maintenance still remains for you:

You wrote:

However, we are thinking that our toilet will require some sort of a daily maintenance run to initiate the smoldering process.

Tricky, very tricky... Getting ordinary users to do any maintenance on their toilets is very hard... (except for special toilet enthousiasts like you and me!). Maybe you have a chance if it involves only pressing a button (that could be automated?). Or what kind of maintenance activities do you envisage at this stage?

Regards,
Elisabeth

Dear Steve,
Thanks for addressing all my questions. I’m keen on hearing more about your progress and how you tackle these challenges; so please keep posting updates!
Best wishes!
/Kim

Dear Kim,
Thanks for your questions.

- From what can be seen in the video from the Reinvent the Toilet Fair in Seattle, August 2012, the system was still very much a laboratory set-up; have you been able to advance towards a system that could be installed in a household or a multi-family building? I guess this question is also related to the cost of the system; will it be possible to achieve a feasible system in economic terms?


Our current target for Phase 2 is a 10 person scale toilet that can be used in household or multi-family building. As with the other grantees our target is to go below 5 cents per user per day.

- From a technical point of view the system looks quite complex, with a lot of mechanical components. What are your strategies to sustain the system in time considering the system complexity and your target context of slum and rural settlements?

Again our system is constantly evolving and we are working on reducing mechanical / user touch points. We aim to have the simplest minimal design that can work. We will be field testing our Toilet in both an urban slum and two rural villages in Bangladesh.

- The system also seems quite labor intensive; what will be the requirements when it comes to operating and maintaining the system for the users?

We would like to maintain a user experience that mimics conventional systems. However, we are thinking that our toilet will require some sort of a daily maintenance run to initiate the smoldering process.

- You mention that the smouldering system is self-sustaining, but I guess that you need a constant input of fuel? What type of fuels can be used and what quantities are needed?

Our goal is to have the reaction self-sustaining. At a ten person scale this is proving to be difficult and we are investigating alternatives. The fuel is human waste - and roughly 3 kg of solid waste per day based on 10 users.

- Finally, have you considered the potential for reuse? For example have you analyzed the contents of nutrients in the final waste streams?


We are hopeful that the sanitized ash can be used as a soil conditioner. On the liquid side of the treatment there is more potential for reuse and we are looking at analyzing the available nutrients, heat, and energy.

I hope this was informative. We are continuing to iterate our design and have moved away from the bench top setup you see in the materials. We are not yet at a point where we have integrated modules and once these have been further refined / tested we will post more information.

Cheers,

Steve