Dear Elizabeth,

Unfortunately, I don't know the exact reasons why the municipality has not continued with the use of the LaDePa technology.

In my opinion, it is a great idea but the costs were high and the process was not optimized enough due to the lack of understanding of faecal sludge characteristics and the drying process. Maybe a previous laboratory work to its implementation in the field would have been more suitable. Indeed, the LaDePa technology was firstly implemented at a demonstration scale, then a pilot-scale study was conducted. Maybe the opposite would have been preferable. I agree with you that there is a lack of impulsion for the jump from the R&D phase to the real world, but it is also too risky to jump the preliminary R&D stage, as happened to the LaDePa and others.

However, as told before, the LaDePa can return to the field, and hopefully then the designers and operators will take into consideration the knowledge and data generated during the pilot-scale research. 

Kindly,
Santiago

Hi Santiago,

Someone should write a paper about the LaDePa * case and let it be a warning to everyone else... Here is a technology that seems to be sound, not too complicated, seems to deliver on its promises. And yet, it hasn't made it beyond the one pilot scale installation. Is it confirming the saying: "Pilots never fail, pilots never scale"? What can we learn from this ( learning from failures )? How could things be done differently? What are those management and finance constraints exactly?

I think it would be great to see a paper on that. We see so much research published about testing out new technology in the lab and in some few demonstration sites. But how to get something out into the real world and scaled up - we are still pretty bad at that, it seems. 
Unless there was something wrong with LaDePa that I am not aware of.

Regards,
Elisabeth

* For those unfamiliar with this process: LaDePa is a faecal sludge pelletising machine that was developed in eThekwini (Durban); we have a thread about it here that spans from 2011 to 2018: 
forum.susana.org/280-faecal-sludge-treat...kwini-durban?start=0

Dear Elizabeth,

Once again apologies for my slow answer.

Unfortunately, there has been no progress on the implementation of the LaDePa, since the last posts from Dave Wilson and Rein Buisman.

To my best knowledge, the eThewkini municipality is still interested in this technology, but there haven't been any concrete advancements. It seems to me that the LaDaPe implementation has been limited due to management and finance constraints.

At least, the outcomes of my investigations concerning LaDePA (in the uploaded report) have brought a better understanding of faecal sludge drying characteristics and have shown the viability of infrared drying for faecal sludge treatment in a general context, even though my investigation has not been reflected in the full-scale process (for the moment).

Kindly,
Santiago

Thanks also for sharing these reports.
The report about LaDePa is from 2018. Would you be able to give a general update on where that technology now stands, with regards to full-scale implementation? If yes, perhaps best in this thread: forum.susana.org/280-faecal-sludge-treat...urban?start=36#26078

Many of us got very excited about LaDePa a few years ago but is it again a case of a technology not making it past the pilot scale to full scale implementation? Due to hurdles that are not really technology related but to do with financing and management?

Elisabeth

Dear colleagues,

I have uploaded in the SuSana library the final report from a project about the characterization of faecal sludge from pour-flush toilets (Volume 1) and the LaDePa process, an infrared dryer for the treatment of faecal sludge from pit latrines  (Volume 2). The project was funded by the Water Research Commission from South Africa. The link to access the document is as follow:
www.susana.org/en/knowledge-hub/resource...library/details/4109

Please don't hesitate to contact me in the case of any doubt or question about the report or the project.

Kindly,
Santiago

Summary of the report:
- Volume 1:
Volume 1:
In South Africa, the Pour-Flush system is viewed as an upgrade from the Ventilated Improved Pit latrine (VIP), which is the standard for basic sanitation in the country. PID successfully ran a pilot scheme involving the installation of approximately 25 Pour-Flush latrines in the greater Edendale area (Slangspruit, France and Azalea) outside of Pietermaritzburg in the province of KwaZulu-Natal, South Africa. The Pour-Flush systems installed in this area by PID were used for the basis of this research project. Sludge was sampled from selected pits repeatedly over a period of 11-months. The sludge was analysed chemically, physically and biologically to provide a base understanding of the sludge characteristics and possible mechanisms occurring in the pit. The filling rates of the pits were also monitored, as this is important information for planning future pit-emptying schemes and pit design.

- Volume 2:
In 2009, the eThekwini Municipality (Durban, South Africa) set out to empty over 35 000 VIP latrines, which were already full, and dispose of the sludge in an environmentally safe way. This led to the development of the Latrine Dehydration and Pasteurisation (LaDePa) machine, manufactured by Particle Separation System (PSS), to dry and pasteurize faecal sludge using a combination of convective and infrared radiation heating. A laboratory-scale LaDePa was installed in the Pollution Research Group (PRG) laboratory, situated at the University of KwaZulu-Natal, Durban. Its objective was to understand better the drying process in the LaDePa process and optimize the operation of the full-scale machine. The research project focussed on two main aspects: (i) study of the drying behaviour of the faecal sludge in the LaDePa; (ii) determination of the biological, chemical and physical characteristics of the dried sludge in order to evaluate its reuse in agriculture or as a biofuel.