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Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
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Re: Recording of presentation: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS)
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I'd like to chime in here and very belatedly answer some of the questions brought up about the Omni-Ingestor. I'll start by giving a quick overview of the OI and a bit of a status update.
The OI is intended allow emptiers to access pits/tanks (vaults) that currently can't be reached by vacuum trucks, and pump material that is consolidated (thick, up to 40% solids, shear strength values of 2+ kPa, un-pumpable by most vacuum trucks, typically removed manually) and thicken the sludge to reduce the volume that needs to be transported. The objective is to increase market reach, reduce transportation costs, and increase profits. That's it in a nutshell. This, of course, is no easy task. Over the course of the project, the organizations working on the project of developed a number of unique and interesting technologies, some of which are actually useful and will find their way to commercialization. In fact, most of the subsystems needed to make a fully-functional OI work in principle or practice. The one challenge we have yet to overcome is the development of a dependable, viable, and sustainable sludge thickening system.
Aware that progress on the sludge thickening system could delay the project, the foundation wisely split the project into two parts: 1) pumping, and 2) mobile pre-processing. While development of the Mobile Pre-Processor (MPP) is lagging, the OI pump development has been moving along. All three mechanical pumping systems being developed have gone into domestic field testing and two have completed that testing. The last pump is expected to complete it's testing in September. After that, one or more pumps will be go through a revision cycle based on lessons learned from the testing and more units built that will be sent overseas for foreign field testing.
On to answering some questions:
Chris Buckley asked how the team will empty very thick sludge. As Mbaye pointed out, the vaults in Dakar have a low solids content. But, solids do accumulate in pits. For the Dakar market, I would suggest that fluidizer is all that is needed to enable thorough emptying. One of the companies working on the OI project, Synapse Product Development, incorporated a simple means of fluidizing vault contents into their pump design. The SPD pump is taken to the vicinity of the vault. It draws material into a tank and then pushes the material out to whatever vehicle/tank is being used to transport the sludge. When it is necessary to break up consolidated material, a valve on the discharge is used to redirect the liquid back into the pit through a separate hose with a simple nozzle on it. The septic tank company here in Washington that used the pump for about 3 months loved it. This could be easily adapted to the vacuum trucks in Dakar. Alternatively, an Omni-Ingestor pump capable of pumping thick sludge could be used (once the pumps are ready for commercialization).
A comment related to Chris' question about GIS-tracking. The OI pump is intended to have a GPS receiver on the Pit-Side Unit, so not only will you know where the truck is, but have a very good idea of where the pit is.
Nelson asked about the size of the OI. If we are only talking about the OI pumping system and related equipment (power, hose reel, etc, and not the MPP) everything will take up the bed of a mid-size pickup truck. The PSU itself is about the size a 55-gallon drum...maybe a bit taller. I'll post some images in a separate post.
Elizabeth commented on the maintenance issues associated with the OI and pointed out that vacuum tankers are not well maintained. This is definitely a concern. While a number of issues related to maintenance can be addressed in the design phase, ultimately, owners need to do maintenance, have access to the parts, be able to afford the parts, and have the know-how to perform the maintenance. Most of this is beyond the scope of the project but it isn't being ignored. For example, the control system developed for the OI pump and MPP has the ability to communicate the health of the machine to the owner. Future efforts may take advantage of this. I hope that at some point, the OI owner can log onto a website and not only see the state of his system, but that maintenance issues can be predictively identified, appropriate actions suggested, and repair parts be ordered and shipped in advance of the issue disabling the system. The website would also include maintenance manuals, schematics, how-to-videos, and a blog for owners to share stories.
Elisabeth also posted an image of an OI pump/MPP system trailer. The image presents a volumetric study of an OI concept intended to show how small the MPP could be. A similar system was built and tested but that design is not currently being developed.
I hope this clarifies a few things.
Cheers,
Andrew
President/Founder of Beaumont
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
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Or go to time 1m:08s here:
The Q&A session starts here with a question by Andy Narracott (WSUP) about how ONAS (as a single entity in charge of sanitation) was created 20 years ago:
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
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I would like to point out that there is also this presentation available that was given by Mbaye Mbéguéré at FSM3 in Hanoi in January 2015:
Market Structuring of Fecal Sludge Management for the Benefit of Poor Households in Dakar:
www.susana.org/images/documents/07-cap-d...1-1-3-1-Mbeguere.pdf
(the rest of the presentations from this conference are accessible here: www.susana.org/en/resources/conference-m...s-2/97-2015/259-fsm3)
His last slide:
Key Results
- First contract signed for the operation of 3 FS processing plants in Dakar
- A customer management platform (call center) that will offer affordable service fees to poor HH in Pikine / Guediawaye
- Project leadership invited at ONAS weekly board of Director meetings
- Improved relationship between ONAS (national authority) and none-pipe sanitation service providers
- Increased visibility of FS emptiers job profile (TV interviews, participation to leading international events, trained personnel)
- Database of 59 000 HH Septic Tank have been referenced.
- Database of 135 trucks referenced
- Network of partner for testing innovative technologies and business model
- A reference case for many other utilities
forum.susana.org/forum/categories/142-up...n-for-the-urban-poor
Elisabeth
Freelance consultant on environmental and climate projects
Located in Ulm, Germany
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
Thank you to find enclosed in English the magazine “Boues mag” number four (N°4) of Program of Structuring of Fecal Sludge Market for the Benefit of poor households in Dakar (PSMBV).
Good reception
Cover page:
TABLE OF CONTENTS
P. 03 Editorial
P. 04 Program for the Structuring of the Fecal Sludge Market for poor people in Dakar suburban areas (Pikine and Guédiawaye)
P. 04 The call center: an innovative tool for the development of the fecal sludge market in Senegal
P. 08 Process for the Certification of Emptying Companies
P. 12 Communication: a key tool for ownership of the program by the stakeholders
P. 16 The delegation of the management of Dakar fecal sludge treatment plants to the private sector: a successful public-private partnership model
P. 21 The emptier guarantee fund : easier access to funding
P. 25 Payment of domestic septic tank emptying service through mobile money: improving people’s financial access to mechanical emptying services
Best regards,
Aissatou Basse
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
Thank you to find below the link of the Facebook account in french of the Program of Structuring of Fecal Sludge Market for the Benefit of poor households in Dakar (PSMBV).
You are most welcome in our Facebook account and you can find all the informations and the news about the PSMBV inside.
www.facebook.com/onasbv
Good reception.
Aissatou BASSE
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You need to login to replyRe: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
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Sorry for the delay in responding. Here are my answers to your questions from your post on 14 July:
You wrote:
I am very interested to learn note about the call centre works that you refer. As well increasing competition and lowering prices for the customer, this may also help with monitoring and regulation. So, as you say, this is a novel idea that can have various benefits.
I would be very interested to hear more about how this is structured according to different customer groups
Is this the same for all types of customer? Are there service levels that are specified that the operator needs to adhere to/achieve?
Is this only for small businesses for trucks? Presumably, the operators have to be registered to receive the request for pit emptying - do they also need to be members of the association of pit emptiers?
Thank you for your interest about the call center. This tool is designed for the emptying of household's pit but it can be used by any entity that needs an desludging service.
It applies to all emptying companies, the smallest to the largest. All these companies are identified, their trucks geolocalized and therefore present in the database of the call center. The auctions do not apply to companies but to individual trucks. You do not need to be a member of the Association of emptiers for your participation in the auction.
You wrote:
I understand that the bargaining is based on one submission from the desludging company. What happens if the job turns out to be much more difficult than they expected due to local situation? The benefit of negotiation on the ground is that the desludger can assess more easily the scale/nature of the job and adjust the charge accordingly. If this is done remotely, then this is difficult. I suppose the desludger can visit the site, but I am not sure that this is realistic. So, there is possibility that the householder ends up paying more than they were quoted for, or the operator takes a loss or does the job poorly to cut costs.... what happens in this case ?
Under these conditions, it is possible that some emptiers, once on the ground, face difficulties in accessing or the customer requires several rotations. In this case, they do not empty the pit and inform the center.
It must be said that the desludgers are very familiar with the neighborhoods in which they operate. The location is listed in the auction and in this case, they adjust their prices accordingly. In a case where an emptier win the market and made a bad quality work, the customer shall inform the Centre during the call quality control (which is done after every emptying activity) and then the desludger is sanctioned. Example of penalty: at its upcoming participation in an auction, the system automatically puts 2,000 FCFA more on his offer; which will make him less competitive.
I remain at your disposal for any other questions.
Regards,
Mbaye
Senegal National Sanitation Utility, ONAS
Dakar, Sénégal
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Re: The Website in english and in french of the PSMBV.
Thank you to find below the link of the website in french and in english of the Program of Structuring of Fecal Sludge Market for the Benefit of poor households in Dakar (PSMBV).
You are most welcome in our website and you can find all the informations and the news about the PSMBV inside.
www.onasbv.sn/
Good reception.
Aissatou Basse
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Re: The Newsletter "Boues mag" N°3 of Program of Structuring of Fecal Sludge Market for the Benefit of poor households in Dakar, Sénégal (ONAS)
Thank you to find enclosed in English the magazine “Boues mag” number three (N°3) of Program of Structuring of Fecal Sludge Market for the Benefit of poor households in Dakar (PSMBV).
Good reception.
Cover page:
TABLE OF CONTENTS :
P. 03 Editorial
P. 04 News
P. 04 Reinvent the Toilet Fair the Promotion of Innovation
P. 06 Second Steering Committee of the PSMBV
P. 07 Innovative Sanitation Technologies in Flooded Areas: Two Prototypes Selected
P. 08 Submission of the first funding application files
P. 9 Project dynamic
P. 9 Ordering desludging services on the phone in Dakar, now a reality
P. 11 Participatory Monitoring and Evaluation (SEP) and Decision Making
P. 14 The WSA agency in the PSMBV project
P. 16 Panafrican Agency for Water and Sanitation in Africa (WSA)
P. 17 Innovation
P. 17 Sustainable access of the poor to adequate sanitation
P. 18 Innovative Sanitation Technologies (IST) in Dakar’s Suburbs: A real need for populations living in flood-prone areas
P. 19 Reduction of electricity costs: A New Approach to behavioral Change
P. 21 RANAS research technology
P.24 Adding value to sludge from wastewater or desludgings
P. 26 Dossier
P. 26 Collective sanitation and management of fecal sludge in Dakar
P. 33 Focus
P. 33 Innovative technology for the value addition to fecal sludge
P. 35 Interview
P. 35 Dr. Doulaye Koné, Project Manager at the Bill and Melinda Gates Foundation
Best regards,
Aissatou Basse
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS)
I am working on a project design for a proposal to BMGF for Freetown and we are considering various mechanisms that may strengthen the lines of accountability between customers and service providers.
I am very interested to learn note about the call centre works that you refer. As well increasing competition and lowering prices for the customer, this may also help with monitoring and regulation. So, as you say, this is a novel idea that can have various benefits.
I would be very interested to hear more about how this is structured according to different customer groups
Is this the same for all types of customer? Are there service levels that are specified that the operator needs to adhere to/achieve?
Is this only for small businesses for trucks? Presumably, the operators have to be registered to receive the request for pit emptying - do they also need to be members of the association of pit emptiers?
I understand that the bargaining is based on one submission from the desludging company. What happens if the job turns out to be much more difficult than they expected due to local situation? The benefit of negotiation on the ground is that the desludger can assess more easily the scale/nature of the job and adjust the charge accordingly. If this is done remotely, then this is difficult. I suppose the desludger can visit the site, but I am not sure that this is realistic. So, there is possibility that the householder ends up paying more than they were quoted for, or the operator takes a loss or does the job poorly to cut costs.... what happens in this case ?
Look forward to hearing from you and learning more from your experiences.
best regards, Jonathan
Principal Consultant – Water and Sanitation
IMC Worldwide Ltd, Redhill, United Kingdom
Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
Skype : jonathanparkinson1
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS)
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Thanks for your detailed responses to my questions!
I think your case could be very interesting for the people following the other discussion thread on "treatment options for septage":
forum.susana.org/forum/categories/53-fae...treatment-of-septage
So in your case, you are using the "conventional" treatment of faecal sludge which consists of:
The three existing fecal sludge treatment plants (FSTP) in Dakar works well. Actually, they consist of a solid/liquid separation process contiguous to wastewater treatment plant. After this solid/liquid separation process via a settling/thickening tank, the solids are dried in drying beds and liquid (supernatant from settlers and leachate from beds) are sent by co-treatment with sewage to the wastewater treatment plant.
The dried sludge from beds are sold as fertilizer to gardeners.
I look forward to hearing more from you, when the results become available, regarding:
- "We launched an international tender and more than 20 bids were received. They range from traditional dry toilet to toilet producing energy and without sludge. The selection is about to be made and detailed information will be shared later."
- "A biogas production unit from fecal sludge is under construction at Keur Massar (suburb of Dakar)."
- "The omni investor is always under development and will be tested in Dakar at the end of this year." (my explanation about the "omni-ingestor": it is a piece of equipment that is meant to treat faecal sludge at the point of the vacuum tanker so that clean water is left behind at the premises and only the more concentrated (thickened) sludge is removed in the vacuum tanker).
A Tale of Two Cities: Accra and Dakar
www.impatientoptimists.org/Posts/2014/06...ties-Accra-and-Dakar
(perhaps the people in Accra were less happy about this, but some health competition between two cities may be a good thing.
![;-) ;-)](/media/kunena/emoticons/wink.png)
Brian wrote:
The National Office for Sanitation in Senegal (ONAS) is a well-run organization populated by professionals who take their roles seriously. They have traditionally owned and operated all of the fecal sludge and waste-water treatment plants in the country. But last year, they privatized the operations of three fecal sludge treatment plants in Dakar, something rare in Africa.
The plants’ new operator is led by Mme. Faye Lena Tall, who owns vacuum trucks of her own. Since taking over the plants she has doubled the hours they are open and improved maintenance, while dramatically improving their profitability. Her agreement has her share her profits with ONAS, who now are happy making more money than they did when they had to run the plants!
Regards,
Elisabeth
Freelance consultant on environmental and climate projects
Located in Ulm, Germany
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You need to login to replyRe: Recording of presentation: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS)
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Better late than never. Finally, I answer your questions.
(1)
Elisabeth wrote:
You said that the institutional set-up in Senegal is very clear, and that ONAS is well placed because it is responsible for everything to do with sanitation. On the other hand, up until now, it was not concerned with emptying of septic tanks and pit latrines, as that's done by the private sector. Isn't that a contradiction? Does that mean ONAS was only responsible for piped sanitation until now, and not for non-piped sanitation?
ONAS is responsible for sanitation in urban centers in Senegal, both public sanitation as individual sanitation. However, the intervention of the ONAS in the field of on-site sanitation was not as important as what is done in collective sanitation. This is the criticism that had been hitherto made to ONAS. With this program, ONAS seeks to better structure the fecal sludge sectorand establish an enabling environment for a better access to mechanical emptying.
(2)
You said ONAS wants to phase out the manual pit emptying. Which technical solutions do you have in mind to make very thick sludge (bottom layers of pit latrines) pumpable? I can only think of dilution with water. Or converting pit latrines to pour-flush latrines maybe (to reduce the amount of solid waste), like it was proposed by Dave Still in a WRC report in South Africa.
It must be said that Dakar, septic tanks are the most represented; nearly 80% of the individual items listed. Under these conditions, the sludge are not as thickened sludge that latrines (as found in many African countries). However, sludge from latrines herein are not pumpable by existing trucks. For this sludge, people still rely on manual emptying. This is why, ONAS attaches particular importance to the Omni Ingestor Which will be able to mobilize this thickened sludge. This machine will be tested in Dakar by the end of 2014.
(3)
How well are the 3 faecal sludge treatment plants that are already operational actually working? Do you have photos? When were they built and by whom? Which processes do they use? Which effluent quality do they achieve on the liquid stream? What happens with the solid part (e.g. dried faecal sludge), what is done with that? Any reuse activities?
The three existing fecal sludge treatment plants (FSTP) in Dakar works well. Actually, they consist of a solid/liquid separation process contiguous to wastewater treatment plant. After this solid/liquid separation process via a settling/thickening tank, the solids are dried in drying beds and liquid (supernatant from settlers and leachate from beds) are sent by co-treatment with sewage to the wastewater treatment plant.
The dried sludge from beds are sold as fertilizer to gardeners.
These FSTP were built in 2004 with funding from the World Bank.
(4)
You mentioned 2-3 innovative toilet technologies suitable for areas that are prone to flooding. What technologies do you have in mind there? UDDTs perhaps (urine-diverting dry toilets)?
We launched an international tender and more than 20 bids were received. They range from traditional dry toilet to toilet producing energy and without sludge. The selection is about to be made and detailed information will be shared later.
(5)
I didn't understand how this call centre works that you mentioned? Does that mean residents can call up a call centre when they want their septic tank emptied and then get quoted the best possible price for their location?
A call-in center that households call whenever they need to have their septic tank emptied, is implemented. While this was an novel addition in and of itself, even more innovative is that every time a call comes in, 9-15 trucks (of ~70 in the system) are invited to participate in an immediate auction where the lowest price earns the opportunity to do the emptying!
Since this system has gone into place, the average emptying fee to the household has dropped over 15% (from $57 to $48) and the new convenience – households used to have to leave their homes to find and negotiate with an emptier, then often negotiate again at their home – has led to more emptying jobs, so the truck operators and truck owners are also happy.
(6)
Can you tell us more about the proposed biogas plant for faecal sludge treatment (you mentioned co-treatment with other organic waste). Is this entirely funded by the BMGF? Is it a full-scale plant? Why would they fund such a plant for you, what is their reasoning behind it? What is the connection here with China?
A biogas production unit from fecal sludge is under construction at Keur Massar (suburb of Dakar). This station is fully funded by the Gates Foundation. The objective is to make energy that once sold, can balance the operation of fecal sludge treatment plants (FSTP) or even make them profitable. Once FSTP profitable, it can participate to reduce the tipping fee and thus affect the cost of mechanical emptying. This station is sized by Beijing University, under contract with the Gates Foundation.
(7)
And finally a question about the Omni-ingestor: how far progressed is the development by now? Do you have any photos? Is there a prototype yet?
I read the report by the company Synapse (www.synapse.com/home-page?destination=node/427) (link to the report: susana.org/lang-en/library/library?view=...p;type=2&id=1718). The report is pretty interesting (thanks to the BMGF for commissioning the report and sharing it). This could be a big business if such an omni-ingestor could be developed. Mind you, I fear the maintenance issue could be a real headache since already the conventional vacuum tankers are not well maintained usually...
The omni investor is always under development and will be tested in Dakar at the end of this year.
Senegal National Sanitation Utility, ONAS
Dakar, Sénégal
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Re: Structuring of the fecal sludge market for the benefit of poor households in Dakar, Senegal (ONAS) - optimising faecal sludge emptying, transportation, processing
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We are still waiting for your answer to Elisabeth: how will you deal with very thich sludge without manual emptying? Will the omnidigestor be able to deal with it (with a high pressure water injection system)?
More infos on the truck being developed by your project?
Hope to see you soon in Dakar and Mauritania,
JM
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