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

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

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=ccbk...p;type=2&id=1154

Yours, Martina.

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 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

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 all,

Thank you for all the replies and suggestions! Su Su, I have not come across anything else besides what I have listed earlier in the thread. We are working on finalizing one our first papers. Also Joeturner, Sanivation seems cool, although I am a bit biased since I am one of the cofounders.

Scalability is a great question and is something we are working through right now with a small pilot of our technology in Kenya. Drying beds also seem very attractive, particularly with the approach that www.waste-enterprisers.com/our-businesses/ is taking.

SuSu, I'd love to help advise you on your project. Is there a specific question you are looking to tackle or a resource I can help you find? The more research done on solar sanitation the better!

all the best,
Andrew

Ah fair enough, I fell into that one didn't I?

I think the idea is reasonable, although I'm wondering if it would require too much equipment and knowledge to operate on a microscale, and I don't know enough about solar cooking to know how big these things can be constructed.

On a mesoscale, it would be nice to have some kind of continuous belt system avoiding a lot of handling. I am no engineer though, I'm not sure how that could be constructed.

Incidentally, my view is that you ideally want to mechanically dry sludge rather than trying to airdry it as you'll lose a lot of the nitrogen during the first few hours, particularly when it is really wet.

Hello Andrew,

Thanks for your reply. I am interested in the fecal sludge drying by using conventional sludge drying bed with solar water heating system. The concept is that I will use hot water pipe in the sludge drying bed not only to help the evaoporation rate increased( as it is the main operation step in sludge drying bed) but also to disinfect the sludge with the temperature (around 50-60C).

I would like to set up lab scale experimental unit(drying bed with heated water pipe) in my university, and try to analyze the finished biosolid. But the problem what I am thinking is how I can get the solar water heater- I have to design myself or I have to buy (it will be costly for my experiment). I am not quite sure, if the energy department from our university could provide me with that solar collecter because our univeristy was flooded last year.

I would wonder if you could suggest me on this idea. Looking forward to you!

Best regards,
Su Su