SuSanA - Forum

Re: Diversion for Safe Sanitation - Grant on Advanced Toilet with On-Site Water Recovery (Eawag and EOOS, Switzerland and Austria) - by: bernhard

Tue, 14 May 2013 21:02:04 +0000

We are happy to announce that we brought our toilet prototype to Uganda, Africa for user testing.
The feedback we got so far is very positive but we also learned some valuable lessons that will help us to further improve the design.

Re: Urban sanitation solutions for high-use, flooded, and difficult to serve areas in Haiti - by: gitum

Sun, 12 May 2013 21:44:45 +0000

Dear Andrew,

It’s a very interesting project. I also pursue my PhD on WASH issues in Onaville in Canaan area, Haiti which increase my interest on your project. If you don’t mind, I also would like to ask you couple of questions regarding to your work.

How often do you collect excreta from the collection bin below the toilet for transferring it to a composting site (every 6 months or so)? How far and how big is the composting site? How do you manage the composting facility?

I am also curious on your community involvement work. Currently, we work in collaboration with a local NGO, TECHO. TECHO informed us that there is lack of local sanitation expert in the area to start the community education on WASH. How did you solve this issue? Did you work with SOIL or another Organization? Also, how long did the community awareness education take?

Moreover, in my previous research I come up with the problem of helminths in Haiti. I saw from your presentation at FSM-2 Conference that 60°C, 1 week hemophilic composting process will be enough for pathogen removal. Still, I am curious if you have any information on helminths.

Best,

Gökce

Re: Novel spray paints for self-decontaminating latrine coatings (University of Texas - Pan American, USA) - by: JKMakowka

Sat, 04 May 2013 12:55:02 +0000

Yes, door-handles, anal-washing shower handles and toilet flush buttons seem to be almost the only interesting application of this.

What I mean is that toilet surfaces rarely actually have a problem with hygiene, e.g. there is little reason why one should disinfect them (there are more bacteria in your keyboard then can be found on a typical toilet seat).
Now if it was actually cleaning them, in the sense of removing stains I would agree that it makes sense, but I doubt it will have much effect on that.

The main problem in sanitation is to disinfect the fecal matter to allow for safe agricultural reuse, and that problem can't be addressed by your proposed method I guess.

P.S.: Most VIP latrines are intentionally build as dark as possible inside (to not attract flies into the inside), so photoactivating would not work on the toilet seat there anyways.

Re: Novel spray paints for self-decontaminating latrine coatings (University of Texas - Pan American, USA) - by: cecile

Fri, 03 May 2013 14:37:06 +0000

Hi Yuanbing,

Your reseach is very innovative and new to my field of knowledge so sorry in advance if my question is weird.
In order to know the efficiency of this paint in decontaminating, do you contaminate first ? And if so, which pathogens did you inoculate ?
For example could there an application for toilets in emergencies and for cholera outbreak ? For flues ? intestinal bacteria ?
I would see an intesting application on door handles for example.
thank you !
Cecile

Novel spray paints for self-decontaminating latrine coatings (University of Texas - Pan American, USA) - by: MaoatUTPA

Thu, 02 May 2013 15:38:43 +0000

Dear all,
My turn to introduce to you my grant from the Gates Foundation. This is very much about chemistry and fundamental research, so here goes:

Title of grant: Novel spray paints for self-decontaminating latrine coatings
Subtitle: Heterogeneous Nanomaterials with high decontaminating efficiency, high contaminant adsorption and broad solar spectrum utilization
Name of lead organization: University of Texas - Pan American
Primary contact at lead organization: Yuanbing Mao
Grantee location: Edinburg, Texas, USA
Developing country where the research is being or will be tested: China; India; and/or US

Short description of the project:
The proposed spray paints consist of heterogeneous nanomaterials with three nanocomponents. Each component is tailored to address a different demand (e.g. high decontaminating efficiency, high contaminant adsorption, and broad solar spectrum utilization), so the resulting paints will exhibit synergic properties by integrating the individual nanocomponents, realizing full potential of latrine coatings in terms of self-decontaminating performance (e.g. durable, affordable, able to be mass produced, easy to clean, and smooth). More specifically, one nanocomponent can absorb visible and infrared lights, another nanocomponent possesses strong adsorption capability to contaminants, bacteria and fungi, and a nanosized ultraviolet photocatalyst serves as the base component. With appropriate chemical modifications, the proposed three-component nanomaterials can be readily incorporated into commercial spray paints as self-decontaminating latrine coatings with enhance cleanliness.

Goal(s): The goal of this project is to develop spray paints that will exhibit synergic properties by integrating the individual nanocomponents, realizing full potential of latrine coatings in terms of self-decontaminating performance.

Objectives: The main objective of this project is to make more efficient use of sunlight by the resulting coatings in practical sanitary applications. It also aims to select stable nanocomponents to make the coatings resilient to aggressive environment. Moreover, the spray paints are attractive and flexible by possessing various colors like existing paints and being fitted into various pan/squatting platforms for affordable applications.

Start and end date: 27 September 2011 to 31 October 2013, final report due 15 January 2014

Grant type: GCE R7
Funding for this research currently ongoing (yes/no): Yes
Research or implementation partners: N/A
Links, further readings – results to date: N/A.

Key components:

Synthesis and characterization of compositionally and morphologically controlled three-component nanomaterials.
Incorporation of the nanomaterials into commercial spray paints (such as Krylon and Dupli-Color) for sanitory applications.
Evaluation of self-decontaminating activities of the spray paints.

What we demonstrated in the presentation (see attached below) is that the developed nanocomposite photocatalyst possesses strong adsorption capability to contaminants. So far we used a toxic dye molecule, i.e. methylene blue, as an example. And our next targets will be bacteria and fungi. It is important to bring contaminants close to photocatalysts' surfaces to improve self-cleaning effectiveness.

Recently we developed a very facile and low-cost procedure to coat the common photocatalyst TiO2 with adsorbant carbon. The products show much faster photodegradation performance. I am trying to file a patent, so not much details were given on the preparation procedure in the presentation.

I have not done any calculation on the costs yet, but am very confident it is facile and cost-effective. We can easily use autoclaves to make the mentioned nanocomposite photocatalysts.

Current state of afffairs:
So far we successfully demonstrated the facile combination of photocatalyst and adsorbent to enhance the adsorption capability to contaminants, and hence improve self-cleaning effectiveness. At the meantime, we also have certain success on the enhancement of absorbed solar portion to improve self-decontamining efficiency. Of course, the selected ultraviolet photocatalysts possess oxidation potential high enought to destroy contanimants, i.e. strong self-decontamining strength. The next step is to keep improving the solar absorption efficiency and to combine the enhanced adsorption efficiency to contaminants with improved solar absorption capability, so to make the final desirable nanostructured photocatalysts.

Biggest success so far:
As mentioned in the previous point, it is the facile combination of photocatalyst and adsorbent to enhance the adsorption capability to contaminants, and hence improve self-cleaning effectiveness. Previously there were some similar reported studies, but none of them are as facile, cost-effective and efficient as ours.

Main challenges/frustration:
It is necessary to keep improve the solar absorption efficiency, to make the proposed desirable photocatalysts with broad solar spectrum utilization and high self-decontaminating strength for toilet seat coatings.

To better understand the adsorption concept, we can use a metaphor here. Someone tries to catch fish in a lake. If he/she just uses bare hands, it is difficult. With the help of a hook and bait, he/she impales fish first. Then fish can be caught much easier. So for our adsorption studies which demonstrated fast photodegradation performance, the photocatalyst is the fish person, the carbon coating is the hook and bait, toxic dye/bacteria/fungi is the fish, and the fast photodegradation performance is similar to faster/easier fish catching.

I am happy to answer any questions about my grant that you may have.

Regards,
Yuanbing

++++++++++++++
Yuanbing Mao, Ph.D.
Assistant Professor

Department of Chemistry
University of Texas - Pan American
1201 West University Drive
Edinburg, TX 78539-2999
USA

Web: portal.utpa.edu/utpa_main/daa_home/cose_...dstaff/chemistry_mao
Blog: maolab.blogspot.com

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: chuckhenry

Thu, 18 Apr 2013 02:56:42 +0000

I prefer to have a (at least a partially) composted product come out of the end of the chamber - much better looking as a soil amendment! We have, however, had situations where the solids dried out quickly due to too much sawdust being used (the family added extra sawdust in addition to what our dispenser provided because she said her children had never NOT had diarrhea and she wanted to keep the toilet clean). In one sense, this drier state may accelerate pathogen dieoff, but I personally object to having an end product that has recognizable dried feces. Not had much of a fly problem in any of our demos so far - presumably because the moisture/temperature is always in a good range for rapid composting. My personal prototype I was using/testing in my basement did have some very small black flies show up - but they disappeared when i started venting and reduced the excess moisture.

I'm sure we will run into conditions that promote fly problems in the future - we'll tackle that problem when/if it shows up!

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: JKMakowka

Wed, 17 Apr 2013 06:16:00 +0000

Interesting, so you don't actually try to dry the solids as in the classic UDDT approach? How do you prevent excessive smell and maggot/fly larvae infestation etc.?

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: chuckhenry

Tue, 16 Apr 2013 16:24:39 +0000

About moisture and air, Elizabeth -

"How do you get enough air and moisture into it for composting?" As you know, feces are about 65% water, sawdust varies but can be anywhere from 20% to over 50% water; and that the ideal moisture for composting is between 40-60%. So, one could assume that initially the mix of materials is about right for ideal composting. (Obviously different cover materials will yield different initial conditions - my favorite cover material is used coffee grounds! And yours???) We have a passive air ventilation system (black pipe) that does a great job of moving the air from the toilet seat up through the vent via heating by sunlight. That is more than adequate, and in fact may dry the compost too much through the compost chamber. We have found both situations - in Ecuador, the material dries out too much, in my house in the mountains outside of Seattle, i have experimented around with venting and have greatly reduced the moisture loss - can actually achieve a little leachate (the CO2 evolves, the moisture is left behind). Moisture is definitely a parameter that we are in the process of fine-tuning over our continued development of new prototypes. And we certainly expect to have to adjust the system(s) for various climactic conditions. For example, our next phase calls for demonstrations in the hot humid, hot arid, and the cool Andes.

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: chuckhenry

Mon, 15 Apr 2013 15:28:49 +0000

Hi Elizabeth,

Blockage - in one of our earlier models (30cm dia pipe, 2 m long) we had trouble turning the auger when it sat too long, but not an actual blockage. Since that time, we've gone to a 20cm pipe and 1.5 m - more for cost reduction than blockage problems. This greatly reduces torque on the axis, as you would imagine.

Our latest prototype has additional features to help mix and breakup the materials Please suggest something to test!

And, yes, the auger is that long to get a good start on the composting - to make it an acceptable looking/smelling material to store for required pathogen dieoff.

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: chuckhenry

Mon, 15 Apr 2013 14:48:54 +0000

I'm pleased that the auger is being used in more toilets! It makes so much sense to use it to add mixing, aeration and movement, doesn't it? I hope more composting toilets will adopt this idea - and improve/add features that neither EcoSan nor El Taladro currently have - while, of course, respecting each of our unique designs.

A little history: the original 'Earth Auger' (a.k.a. El Taladro de la Tierra) was built in 2001 - my first composting toilet as a potential tool for a University of Washington study abroad program in India. At that time it was affectionately called 'The Poo Screw.' Later, it was disclosed to the University of Washington (who did investigate the similarities of EcoSan with my design).

Since that time Marcos and I have added and tested a number of features (including single lever flush, auger turning and cover material distribution) - many of the developed during the period of our Phase I Gates Foundation grant - and still with the goal of being able to sell the unit for about $150.

To have two great products that have been developed independently (I assume) validates the concept, wouldn't you agree?

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: jkeichholz

Sun, 14 Apr 2013 18:18:27 +0000

re: the South African version - I've found some more snapshots from an excursion by (then) GTZ-ecosan in 2003:

I believe the difference to be the sawdust vs. fan.

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: christoph

Sat, 13 Apr 2013 15:48:25 +0000

I looked up the old posts in ECOSAN res.
Richard Holden posted in 2010 that they where still beeing manufacured (post #6102), the first time they were mentioned by Detlef Schwager #3089.
Actually I realized the discussion was started by Chris Canaday, so I guess you know the South African people.
Attached you find the installation guide with a lot of useful data (taken from the technical area in Yahoo ecosanres)

Yours
Christoph

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: christoph

Sat, 13 Apr 2013 14:12:20 +0000

Dear Marcos,
I remember a very similar product from South Africa.
Could you explain where is the difference to the Toilet shown in this video

from this company http://www.ecosan.co.za/product_info.html?

I remember there was quite a discussion in ecosan res icluding prices, failure. It is (? was?) a plastic molded, ready to sell, product. From what I recall it was not too cheap.
From my understanding it is almost the same. It would be interesting to understand the differences.

Thanks a lot
Christoph

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: muench

Fri, 12 Apr 2013 20:19:44 +0000

Dear Marcos,

Thanks very much for your detailed description of your research grant with all those photos and videos, much appreciated! I wish you all the best with this project!

But I always immediately worry when I see an auger (same as "screw conveyor" in this context?) to move faecal matter from A to B. I suspect it could easily be blocked and then it would be very, very messy and difficult to repair it, wouldn't it? Do you have photos of such an unblocking activity?

Also, I wondered why the auger has to be so long, but then I realised that this is your composting chamber, right? How do you get enough air and moisture into it for composting? The air cannot get in from the length of plastic pipe, only at the front and back, right? Do you have photos and analyses about the compost that comes out in the end (in your ppt it says that it stays in the pipe for a total of 1-4 months)?

COMPOST EXIT
A small amount of
compost exits after
each flush, having
been detained for 1-
4 months
(depending upon
number of users)

Regards,
Elisabeth

Re: The Earth Auger Toilet: Innovation in Waterless Sanitation (Fundación In Terris, Ecuador) - by: mtfioravanti

Fri, 12 Apr 2013 15:24:27 +0000

Hi Dorothee!

Thanks for your questions.

Those pictures are in Ecuador, in a periurban community called Monte Sinaí. There are more than 250.000 people living withaut sanitation services; no sewage, just improvized and non safety solutions. We have been testing prototypes in this community during the last 5 or 6 years, but during 2012 we tested 6 of our lastest versions.

The current cost is around $200 depending on the version. But now we have found ways to do it a lot cheaper, even without going big scale technologies like plastic injection. The goal is to produce it for less than $150, and we are realizing that is toatally possible with the lastest approaches. My colleague Chuck Henry can tell more about this.

We have big plans for our second phase, but it is still under evaluation by the Gates Foundation. I prefer to wait until we have official agreements, but we are working on partnerships in different subjects: pathogens elimination, market research and business plan, local authorities in housing, health and sanitation, testing parts and components, etc.

Regards!, Marcos