Dear Tsepo,

Please have a look at the attached publications. They give a good insight in sludge conditioning.
I trust, you will find them useful.

Regards,

F H Mughal

Tsepo wrote: In my search I found this link
www.researchgate.net/post/How_to_dissolve_precipitated_sludge2

Can anyone please elaborate on it for me. Reiterating what I mentioned earlier (I'm just an entrepreneur not scientist)

As far as I can tell this has nothing to do with what you want to do (but is rather about re-suspending a precipitate in a chemical reaction in a laboratory).

There are various products (Alum, Ferric-chloride, Lime, Chitosan, other commercial polymers etc.) available to improve thickening sludge in a sludge drying bed, but the material dug out of pit-latrines is notoriously difficult to de-water especially when a large part of it is still relatively "fresh".
In any case, such additions will just speed up the process a bit, and if you have sufficient space in your drying bed they are rarely cost efficient (and Alum for example will cause issues in the final sludge disposal as Chis Canaday has already suggested).

From low cost/low maintenance point of view "planted sludge drying beds" (with no chemical additives; see chapter in the book linked above) are probably the best idea for a setting like you have in Lesotho. No need to actually use the plants (reed, papyrus, elephant grass etc.) grown in it for anything, but as Chris mentioned those can be an additional source of income which from an entrepreneurial point of view shouldn't be missed.

Dear Tsepo,

I have no idea about the chemicals mentioned in that link, but I think it is very unlikely to be practical, cost-effective or good for the environment.

I understand the cultural resistence to thinking that feces can be useful for anything, but they are a natural part of life and have always (until recently) gone back to the soil, replenishing its fertility. Any health risk, in the form of disease pathogens, will die out over time, as the material dries out and soil microbes predominate.

This concern is why I did not suggest any plants for human consumption. If you plant grass for animals, your company could hygienically raise cows, goats, rabbits, etc., cutting the grass and giving it to them in their pens. In general, the grass, bamboo or other plants would be harvested after a prudent time of drying and decomposition, in the various Planted Drying Beds that are used in rotation. Eventually, when the beds fill and dry over a prudent time, you can sell the beautiful, rich soil, or, even better, use it yourself in agriculture and sell the beautiful produce. People may ask, ''Was this sprayed with chemicals?'' and you can say, ''No, it's all natural.''

The book that JKM cited will certainly go into more detail, but there are simple, mechanical methods for pumping out latrines, in a way that is safe, practical, and dignified for you and your employees. One such apparatus is the Gulper:


Another is this mechanized Excrevator


Best wishes,
Chris Canaday

Dear Chris/JKMakowka

Thank you both for your feedback, however have you thought of the mentality people like me have, eg planting food in sludge to human consumption (even if the sludge has been worked on to make it valuable safe fertilizer, for the fact that its human waste, it still does not go well with consumption for crops planted for consumption. (I am not the only one with this thinking)

Therefore working on the Feacial sludge for crop fertilization maybe a good recyclable and environmentally viable process, however in terms of persuading people to buy into it IN MY COUNTRY may take a long persuasion

In my search I found this link
www.researchgate.net/post/How_to_dissolve_precipitated_sludge2

Can anyone please elaborate on it for me. Reiterating waht i mentioned earlier (i'm just an entrepreneur not scientist)

Dear Tsepo,

I understand why you ask that question, but I think the answer is that such magic does not exist ... and, if it did, would that be a chemical that we would want in our soil?

I suggest it is better to apply natural processes and one of the best options for treating fecal sludge is the Planted Drying Bed:
ecompendium.sswm.info/sanitation-technol.../planted-drying-beds

I also think it would be great to get the users to switch to Urine-diverting Dry Toilets, so as to not produce disgusting sludge, but instead safe, liquid fertilizer (urine) and beautiful soil.

Good luck with your business and please let us know how things go and if you have other questions. One suggestion: try to find a valuable plant that will grow in these drying beds, such as grass to feed cows, bamboo for baskets, biomass for charcoal, etc.

Best wishes,
Chris Canaday

Great to hear that you are interested in starting a Fecal Sludge Management business!

You will find rather comprehensive information on possible treatment steps and other relevant factors in this recent (and free to download) book:
www.eawag.ch/forschung/sandec/gruppen/EW...cts_ewm/fsm/index_EN

Good Day All

I am interested in business of recycling pit latrines in Lesotho. About 80% of the population uses pit latrines and my business ethics in me is that of asking from the learned world to assist with a chemical i can use to add to the sluge so that the contents precipitates and the liquids evapourates and the solid turns into ash or powder,

The reason for the question is that to avoid digging of pit latrins once one is full can be delayed in that once the contents are shunked into powder or ash may delay or cut cost in digging a new toilet

Assistance or guidenace in matter would highly be appreciated

Kind regards
Tsepo