Dear Sadiq,

See the very fresh discussion about more or less the same issue with Prem from South-East-India: forum.susana.org/forum/categories/35-bio...rs?limit=12&start=12

All made suggestions are relate to your upcoming DEWATS-project 100% too. In other words just providing to you some "biogas related technical documents" or "blueprints" will end up in big frustration for your community and on your side too.

Furthermore,

Community should be involved in O&M process for sustainability.

Yes I agree to this statement, but keep in mind the coming actual caretakers maybe 3-4 persons will have to run the system on the daily base, not the whole community. Again, I have to stress on this direct profit issue: To do so in a good way this 3-4 persons need more them the blessing by the whole community. A very direct interest is necessary (see Florian's comment!) to keep your (a) DEWATS-system in total running well!

Good Luck
Detlef

Actually, we preferred biogas as it has more benefit on energy. This community has also the scarcity of cooking energy. Biogas will supplement their cooking fuel.

Hi,
that's already good, although some warning here as well: you can't expect the whole community benefitting from the biogas. For practical reasons it's only possible to supply a couple of houses nearby the digestor. So Detlefs suggestion to couple the benefit from biogas with the duty for maintenance of the digestor is a good one. The gas be will probably quite more than the need of a single household, so business needing energy (e.g. restaurant) may be a good consumer.

One more comment: community shared bucket latrines with manual emtpying can't really considered safe sanitation, so by treating the sludge you will only solve the problem partly. Something to keep in mind for longer term planning.

Best, Florian

Dear All,

Thank you very much for your suggestion. Actually, we preferred biogas as it has more benefit on energy. This community has also the scarcity of cooking energy. Biogas will supplement their cooking fuel. Of course, we have to think about increasing production of biogas from human excreta using biodegradable waste from kitchen. Community should be involved in O&M process for sustainability. The area is so congested that, using vecutug for transportation is not possible. Main problem is disposal. We do not have enough space for safe disposal.

I would request you to provide me biogas related technical document.

Dear Shahidul,

Happy to see you in the SuSanA group.

Thanks,
Sadiq

Hi Sadiq,
There are many types of vacutug with long vacuum pipe. You can ask MAWTS-Mirpur (Martin, 01713 384090).
Trenching ground/drying bed may be other options.
You can think about it.

Thanks,

Sahidul

Dear Sadiq,

It is a bit tricky to advice you from very fare, not being real involved.

Option 3, "Stabilization pond" will need the most space and is often a stinking problem for houses nearby.

DEWATS with ABR is a biogas-plant.

Anyway using "old" feacal sludge will not generate much biogas. So try to "harvest" fresh feacal sludge as practical possible and include co-substrates like kitchen and garden stuff and other "clean" organic material.

If you go for that option, keep in mind, just paying the care-takers a salary will not be enough to keep the system running well. The care-takers of this biogas-plant should/must have a very direct benefit from the good functioning of that DEWATS = biogas plant, like cooking for their direct family or small business. In this way they will look very well after the whole system and permanent "capacity buildings" are not a priority.

Please check out your Indian colleagues more nearby: cddindia.org/images/Brochure.pdf

Good Luck
Detlef

Hi Sadiq,

first thing to consider is the desludging and transport. If its currently done in a "very unhygienic way" this should be improved by some mechanical equipment (vacuum truck or cart).

For the treatment, it is important to consider that your sludge is very fresh and thus behaves different than "old" sludge from septic tanks, it is quite difficult to dewater in a reed bed or drying bed and needs to be stabilised first in some kind of aneraobic treatment.

For your options:

1) A biogas digestor could be a good option, especially if there is a use for the gas. However the effluent still needs further treatment. Drying beds or vertical red beeds would be good options I think.

2) Not sure if a ABR works well for thick fecal sludge, otherwise this would be similar to the biogas option

3) Stablisation ponds are good for wastewater, but do not really work well for fecal sludge. You'd need a series of ponds (=lots of land), with one or more anerobic ponds first. High ammonia contents of sludge may be a problem for algae growth in facultative ponds. A pond may be best used as final treatment of effluent from drying beds or reed beds.

Best regards,
Florian

Dear All,
We are facing problem for disposal of feacal sludge from the population of around 18,500. Presently, there are 185 nos. community latrine blocks (one block has five cubicles) with a storage tank of approximately 7 cum capacity. In average, one month interval each tank needs to be desludged. Desludging is going on in a very unhygienic way and disposal of untreated or partially waste is also a health and environmental concern. Land space is very limited within the settlement. Under the circumstances, I am looking for a sustainable solution for feacal sludge management.

The options are-

1) Biogas plant
2) DWATS with ABR & Reed bed filter
3) Stabilization pond

For all the cases land is problem. If we could not manage land inside the settlement for the options 1 & 2 then we have to go for option 3 by managing land at outside of the settlement.

Could you please suggest the best option for the above situation. Location of the settlement is in Bangladesh.

Thanks & best regards,

Sadiq