I recently came across a company called sanivation , which is using a solar concentrator to cook sludge. Seems to be similar in design to solar cookers, I don't know whether it is at all scalable.

Hi Andrew

I have been looking at such option as well here in Switzerland. For a project in the city of bern, I looked at geotubes, kind of very big filter bags (www.tencate.com) as an option to safe place; but it would probably require the addition of a coagulant.
Some work has been done in mountain huts in Europe, e.g.:
www.sanbox.info
www.unibw.de/ifw/swa/Forschungsvorhaben/...lung/schlammtrockner
For a projefe place; but it would probably require the addition of a coagulant.
On drying beds you can also find some information, documents and links here: www.sswm.info/category/implementation-to...reatment/drying-beds
You may also find some articles on the homepage of eawag/sandec (e.g. www.eawag.ch/forschung/sandec/gruppen/EWM/index_EN) they have and are doing a lo of work on drying bed, for instance in Burkina Faso.
Hope this helps somehow.

Dorothee

Hello Andrew,

I am a master student in environmental engineering. I am also interested in fecal sludge treatment by solar drying as my thesis. But I don't know yet, it would be feasible or tangible solution for the large scale treatment or in reality. I has just started reviewing the literature. I wonder if you have done "a paper on the feasibility of using solar energy to treat fecal sludge", and you could share me that paper.

I am also looking forward any idea on the topic.

Thank you

Best regards,
Su Su

Hi All,

I wanted to add a one pager about our project to this discussion (see attached). Also to add clarity to the costs of our system, the original prototype including solar concentrator and fecal container costs $500. In its current form it has the potential to treat waste from 20 households continuously for the lifetime of the system +10 years.

Chris brought up a great point about how we will need many containers. We have designed and are currently fabricating a new system that would integrate with repurposed containers. Each container would cost around $20.

Like many of the sanitation projects out there we are now looking for capital to do a larger scale pilot. Don't hesitate to contact us if you are interested or have questions about our system.

Cheers,
Andrew

Hey Chris,

I'll let Andrew know about your question (and see what's wrong with the email) as he and Emily designed it, but here are some quick answers to your system.

What is the tube made of?

Sheet metal, steel with black paint, it's not the lightest thing in the world- and when it's full of fecal mater it can be well over 40kg

How much does each cost, as you will need a large number?

we're currently playing with the numbers and prototypes for a specific answer, but it's less than $500 at the moment to produce, in Santiago Chile, with a very experienced solar oven maker (among his many projects) It's designed for a community of 20 at the moment and we've found temperatures in the 60's and 70's within hours. Meaning that one family could dispose all of their waste in a day, then the next family would use the system. For peri urban settings, with more people we're playing with ideas on how to increase capacity.

It may be convenient to collect feces in inexpensive containers that can be collected from the households and placed straight into the tube of the oven. This could be a woven, polypropylene rice sack, like I use (see inodoroseco.blogspot.com/).

will have to look into it, email me directly This email address is being protected from spambots. You need JavaScript enabled to view it.

Have you had any experience with this system in cloudy places? I live in Puyo, Ecuador, at the edge between the Andes and the Amazon, which is really cloudy (except for recent changes due to Global Climate Disruption).

We've tested this model solely in Chile, and Santiago at the moment lacks clouds

By the way, I do not think you should call feces collected in UDDTs "fecal sludge", as this connotes solids taken out of the water of sewage.

good point, we'll have to discuss

Thanks Chris!

Dear Sanivation (Chris Quintero, Andrew Foote, Emily Woods, et al.),

(I posted something on your Facebook page but it disappeared ... and a message to This email address is being protected from spambots. You need JavaScript enabled to view it. bounced back.)

Your new system with the tube that goes from under the user to above the curved mirror is very interesting (sanivation.com/solar-technology/). What is the tube made of? How much does each cost, as you will need a large number? It may be convenient to collect feces in inexpensive containers that can be collected from the households and placed straight into the tube of the oven. This could be a woven, polypropylene rice sack, like I use (see inodoroseco.blogspot.com/). Water can still evaporate out and temperatures would likely not be so high as to do anything to polypropylene. And in a short time it is safe, can be opened back up, sacks can be reused, and the dried material could be sent to farms or (if you really trust the solar treatment) reuse it as cover material (potentially mixed with a small percentage of compost or feces stored for a long time at ambient temperature, if we want beneficial microbes to work on the feces and help control smell before they go to the oven.)

Have you had any experience with this system in cloudy places? I live in Puyo, Ecuador, at the edge between the Andes and the Amazon, which is really cloudy (except for recent changes due to Global Climate Disruption).

By the way, I do not think you should call feces collected in UDDTs "fecal sludge", as this connotes solids taken out of the water of sewage.

Best wishes,
Chris Canaday

Dear Andrew,

the colleagues at the University of Bonn did some stuff on solar drying in their Vietnamese project. But I am not sure if just for urine or also for feacal sludge.

But check it out yourself. Here the link to their final report:
www.susana.org/lang-en/library?view=ccbktypeitem&type=2&id=1154

Yours, Martina.

Dear Andrew,

Apart from simple sludge drying beds I have not seen anything else working. Though it seems like a promising way to treat the sludge, it requires a good operation and maintenance system. What kind of incentives do you plan for o&m. What do you want to do with the treated sludge?

Cheers
Christian

Hi SUSANA Community. I am looking to write a paper on the feasibility of using solar energy to treat fecal sludge. Could you share your experience and/or knowledge of projects in this area?

Here are the resources I was able to dig up. Please add an opinions and other solutions you have seen.


Active Solar Drying of Waste Water Sludge

Fate of Pathogens in Sludge Sand Drying Beds at Qateef, Khobar and Dammam: A Case Study

Solar Biosolids Drying:  Harnessing the Power of the Sun to Produce Dry and Safe Biosolids

APPLICATION OF FLAT PLATE SOLAR COLLECTOR FOR THERMAL DISINFECTION OF WASTEWATER EFFLUENTS

Increase the Efficiency of Conventional Sand Drying Beds by using Intensive Solar Energy: A case study from Jordan

OPERACIONALIZAÇÃO DAS ALTERNATIVAS DE DESINFECÇÃO E SECAGEM DE LODO DIGERIDO ANAERÓBICAMENTE

SUSANA member Daneric is working on hot water from solar panels heat the slurry to 70C for about an hour to remove pathogens for a high school in Kenya. Design attached.

I am also currently working on designing solar concentrators to treat fecal sludge.

Cheers,
Andrew

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Comment by moderator: a related thread in 2012 is here: forum.susana.org/280-faecal-sludge-treat...solar-oven-for-feces