SuSanA - Forum

Re: Effective Sewage Sanitation with Low CO2 Footprint (Duke University in Durham, North Carolina, USA) - by: Marijn Zandee

Tue, 21 May 2013 05:01:59 +0000

Dear Aaron,

Thank you for the posts and the updates.

I also have a few questions.

1.) a family size of 10 seems large to me (based on my Asian experience, maybe for SSA this is more realistic). This brings me to the question of how well the process would cope with under-feeding. For instance if some of the children of the household get send to boarding school, leave to work abroad or get married. What would be the minimum amount of people daily using this toilet for there to be sufficient gas to sterilize the effluent?

2.) Why did you select a floating dome approach. My intuition is that it could be cheaper and more reliable to work with a fixed dome concept, but then again I have never thought about such small units, so I may be overlooking something.

3.) For how much flushing water are you designing this? It seems it would have to be fairly low flush in order to not dilute the waste too much.

4.) Similar, if designed for wipers, is the retention time high enough to break down toilet paper. And if designed for washers, is the extra water ok for the mass balance?

regards

Marijn

Re: Effective Sewage Sanitation with Low CO2 Footprint (Duke University in Durham, North Carolina, USA) - by: F H Mughal

Sun, 19 May 2013 11:19:41 +0000

Dear Mr. Joan,

Quite often, the anaerobic digesters are fixed with mixing device to hasten and enhance gas production; mixing the contents; and prevent the formation of scum.

Regards,

F H Mughal

Re: Solar steam sterilizer for treatment of human waste (Rice University, USA) - by: ak00133

Thu, 16 May 2013 15:01:26 +0000

Dear Naomi

Thank you for sharing this project, indeed it looks like the most promising way for small scale waste treatment. A few questions:

1) Is perhaps trying to test for the destruction of Geobacillus
stearothermophilus an overkill, is it often present in fecal sludge?
Maybe treatment times could be reduced if you test for ascaris lumbricoides which seems to be the most resilient helminth present.

2)You have measured temperatures at the top and bottome of the treatment vessel, how does this relate to the temperature in say the center of the waste?

3) Can steam or hot water be produced to pipe underneath a solar drying bed and accelerate evaporation. Therefore the end waste could be used as a fertiliser.

4) Does the steam condense inside the vessel and increase its volume. This may cause transportation issues.

Kind regards

Asad

Re: On-site sanitation based on bio-additives and pit design (LSTH, UK and Tanzania, South Africa and Vietnam) - by: AquaVerde

Wed, 15 May 2013 18:36:54 +0000

Dear Jeroen,

In regard to this by M&B Gates funded project, I found the stated project approach on "Global Access and Intellectual Property" most refreshing, so much different to what we all know about Microsoft, making sure all people receiving the "key" and not only some.

I am not very sure about, the USA might have a clear government policy, that all public funded research results have to be fully accessible by the public. Maybe someone from USA can correct me on that nice policy? Is this real reality in USA?

Beside this refreshing discovery on the "key", I have a more technical question to you, to understand better technical targets behind.

"The unit can be linked to flush or pour-flush toilets,..." This makes me a bit alerted on the "travelling" of the possible liquids involved! I understand, all liquids passing trough an active layer near the surface, where solid waste get digested and then enters a filtration bed where the liquid waste is further treated by aerobic bacteria.

After that, do the treated liquids pass direct through the soil around the pit? Or is the possible pit maybe lined and "you" try to discharge from that aerobic filtration bed by gravity via a biological more active topsoil and vegetation filtration first, before treated water is entering ground water or surface water?

Thanks in advance.

Good Luck and Best Regards,

Detlef SCHWAGER

Re: Effective Sewage Sanitation with Low CO2 Footprint (Duke University in Durham, North Carolina, USA) - by: AquaVerde

Wed, 15 May 2013 07:53:25 +0000

McCarty's Anaerobic Baffled Reactor (ABR) and CHP's (CON2 or prefab ABR's) for "Effective Sewage Sanitation with Low CO2 Footprint"?

Dear Joan,

It seams to me your US-group and the EU funded biogas-group "speetkits" for security related research (2012-2016), working more or less on the same issues involved, but very separated!

In my opinion the existing German containerised ABR + CHP "CON2" (insulated and heated) for mesophilic temperature range in Germany is doing already the "job" your separated groups are looking for. You can use the excess heat of the CHP for the needed thermal treatment to sanitise/kill pathogens in effluent/sludge and might dry the sludge or use the gas straight in a heater. Furthermore heat pumps could be used too.

As Prof. McCarty's (USA, 1981) original ABR-Design is an "Open-Source" and do not has a user restricting Patent attached, you might do your own ABR + biogas heater + heat pump or CHP.

2007 Colloquium on Water - Prof. Perry L. McCarty: (1 h 12 min)

Instate of simple purchasing a German CON2 (45-75kWel. (costs 5,000EUR/kWel.)) you might better do your "own" simple ABR, by stacking two fibreglass body's of ready made prefab ABRs from BORDA e.V., Bremen (Made in Asia or Africa), in an used and insulated container. An additional heating and insulation between the two fibreglass body's could keep the fermenter easier in the mesophilic temperature range in cold climates. Maybe add on top of your self-made ABR an insulated airtight fabrics for simple gas storage above the ABR it self, or store gas in a separate used sea-container (with airtight fabrics) nearby.

To simplify your design you might not use insulation and heating of fermenter, only in cold climates you will need insulated and additional heating of fermenter, in the tropics they "run" easier within the mesophilic temperature range, see many examples of BORDA's very simple ABR's in Asia and Africa.

I hope my hands-on view as an biogas-outsider is heplfull to you and your project/research outcome.

Good Luck & Best Regards,

Detlef SCHWAGER

See:
forum.susana.org/forum/categories/61-wg-...isposal-faecal-sludg

Fecal Sludge Extraction and Disposal system in situ - solar/wind energy driven facility (Shijiazhuang Uni., China) - by: sunnybreeze

Fri, 10 May 2013 18:09:30 +0000

Hi,

I'm Jing Ning, the PI of GCE7 grant "Fecal Sludge Extraction and Disposal system in situ" and I work at Shijiazhuang University of Economics/Beijing Sunnybreeze Technology Inc in China. As you can see from this list there are only two grantees in China from the list of 75 grants in total, and we are one of them:
www.susana.org/lang-en/research/funded-b...nda-gates-foundation

Below you find information about my grant and some results to date:

Title of grant:
Fecal sludge extraction and disposal system in situ

Subtitle: a column-like solar/wind energy driven facility
Name of lead organization: Shijiazhuang University of Economics
Primary contact at lead organization: Jing Ning
Grantee location: Shijiazhuang, China
Developing country where the research is being or will be tested: China

Short description of the project:
Disposal human waste in situ by an column-like facility; Evaporation liquid from raw sewage powered by solar-thermal energy; remove pathogens by raising temperature over 140C; preferred on existing, inexpensive, practical, multi-disciplinary techniques and methods to solve the great challenge in limited term.

Goal(s): The goal of this project is to design a new system for hygienic and adequate pit/tank emptying and extraction.

Objectives:
1) Suitable sunny areas / countries (cover ~0.8 billion@ 2.6 billion without sanitation)
2) Meet the “off the grid, inexpensive, recover resources and remove the pathogens”

Start and end date: Nov, 2011~Mar 2013 , final report 1 May 2013
Grant type: GCE Round 7
Funding for this research currently ongoing (yes/no): yes

Links, further readings – results to date:

Project website: www.nowatertoilet.com/

Video about this project:

See here our Phase 1 report:

Current state of affairs: We are applying for Phase II funding (submitted the proposal one week ago)

Biggest successes so far: Human wastes processing is energy consuming work. It seems that any technique approach most likely practical in near future should be somewhat involving solar energy. we are on the right track and seeing a early morning light.

Main challenges: reduce the cost of the system. A unit is serving for 5~6 people, cost should be about 800 US$ per unit.

And here are our plans for the Phase 2 if we get funding:

++++++++++++++

Application for Phase II Human Wastes Disposal System In Situ - A Waterless Toilet Including Mini Waste Processor

1. Idea:
Phase II proposes a waterless toilet with a complete Mini Waste Processor (MWP) that dries and sterilizes the human wastes in an automatic system. The liquid portion of the human waste is evaporated and the solid portion of the fecal sludge is heated in the evaporator/dryer/sterilizer of MWP. This unit removes the pathogens and transforms the waste into a dried form that is usable as a fertilizer.

The key technologies include:

（1） The previous deliverable, Phase I, was a proof of concept to demonstrate that solar power alone can dry and sanitize the raw sewage. The proposed solar thermal air blower (STAB) of Phase II is a more reliable, safer and lower cost way to transfer heat from the solar collector to the evaporator as high volumes of solar heated air rather than hot oil circulated under high-pressure is used as the heat transfer medium in the Phase II redesign. This simplifies the design as the hot air is used to directly dry the raw sewage.

（2） Phase II proposes an additional Mini Waste Processor that can dry and sanitize the raw sewage by solar heated air. The key idea is to use a Screw and Ball assembly with specially designed balls to that both move small quantities of raw sewage up out of the reservoir where they can be dried and sanitized the hot air from the solar collector. The proposed approach uses readily available levels of technology so that the equipment can be maintained and repaired in even the poorest countries.

Goals: (General)
（1） Pilot test for applicability at ～20 users-scale
（2） Suitable for sunny areas / countries (Toilets for ~0.8 billion of 2.6 billion without sanitation.)
（3） Fully meets the requirement for; off the grid, inexpensive, and removes pathogens.

Goals 2: (Design specifications for a 5-6 member family daily use)
（1） STAB (solar thermal air blower) peak power 4KW equivalent when sun is directly overhead at a minimum air temperature 150C measured at the solar collector.
（2） MWP (mini wastes processor) on sunny day
- Solid waste treatment capacity: ≥10kg/day, (remove pathogen/dewater/shaping)
- Liquid waste disposal capacity: ≥20kg/day, (evaporate all sewage)
（3） Lifetime ≥10years, Manufactures Price <$800USD(Ex-factory price when mass produced)
（4） Robustness; safety for children; easy operation; zero water consumption.

++++++++++++++++++

I look forward to getting your feedback.

Regards,
Jing Ning

Shijiazhuang University of Economics/Beijing Sunnybreeze Technology Inc
PR China

Re: Reinvent the Toilet@lboro - Hydrothermal Carbonization and Odour Issues: User perceptions and experiences - by: KimAndersson

Wed, 08 May 2013 05:15:48 +0000

Dear Sue,
Thanks for your reply. I'm looking forward to learn more about your project progress and findings.

Best regards,
Kim

Reply: Solar steam sterilizer for treatment of human waste (Rice University, USA) - by: njhalas

Wed, 08 May 2013 02:08:56 +0000

The nanoparticles stay in the system and are not carried by the steam that is generated. We have operated with the same nanoparticles for months.

The truth about nanoparticles is that there are many safe ones. The particles in our application are completely benign, but that is besides the point since they remain in the solar steam generator anyway.

Naomi J. Halas

Re: Reinvent the Toilet@lboro - Hydrothermal Carbonization and Odour Issues: User perceptions and experiences - by: Sue

Tue, 07 May 2013 19:38:00 +0000

Dear Kim, Many thanks for your email as well as for your interest in the work we are doing at Loughborough University. Apologies for not getting back to you sooner. I work with Sohail and am responding on behalf of the team. As you say, we are currently developing the prototype, whilst we have some interesting initial findings we will be in a better position to update you on the details shortly. I will get back in touch with more information soon.
Best regards Sue

Re: On-site sanitation based on bio-additives and pit design (LSTH, UK and Tanzania, South Africa and Vietnam) - by: KimAndersson

Tue, 07 May 2013 17:44:25 +0000

Dear Jeroen,
Thanks for your reply and for sharing the project report.

I think I still have some doubts regarding the liquid effluent that you will infiltrate to soil (from your vermi-compost system connected to a flush toilet). According to the result of the effluent quality analyses in your report, the levels of COD and bacteria are still high; hence uncontrolled infiltration could have negative impacts on groundwater quality. However, it is not clear if the test of the prototype in the report includes the filtration bed that you mention on the homepage. Would be good to get some more details on this matter.

Best regards,
Kim Andersson

Re: Solar steam sterilizer for treatment of human waste (Rice University, USA) - by: Marijn Zandee

Mon, 06 May 2013 07:58:06 +0000

Dear Naomi,

Thanks for your post, this seems quite interesting. Some questions that I have:

1.) Do you need to refill the nano particles, i.e. do they stay in the system or are they "consumed" / leaked?

2.) If the second, are there any health risks associated with nano particles? (Thinking along the lines of asbestos here.)

Kind regards

Marijn Zandee

Solar steam sterilizer for treatment of human waste (Rice University, USA) - by: njhalas

Sun, 05 May 2013 02:06:07 +0000

Dear all,

A description of my research grant from the Bill & Melinda Gates Foundation is given below and I welcome your feedback and questions.

Title of grant: A Solar Steam Sterilizer for treatment of human waste
Subtitle: Rapid transfer of a new scientific discovery into a better sanitation technology for the developing world

Name of lead organization: Rice University
Primary contact at lead organization: Naomi Halas
Grantee location: Houston, Texas, USA
Developing country where the research is being or will be tested: Currently in the US, we are proposing sites in Kenya in collaboration with Sanivation (Phase II, to be submitted).

Short description of the project:
Solar steam generation, a recent discovery from the Halas lab at Rice University, is the technological breakthrough upon which this project is based. Light-absorbing nanoparticles, when dispersed in water and illuminated by sunlight, produce steam with only secondary heating of the fluid volume: more than 80% of the solar energy absorbed by the nanoparticles is converted directly into steam, with less than 20% contributing to residual fluid heating. Due to its unparalleled high efficiency, this process produces high temperature steam rapidly, in compact, standalone geometries extremely well-suited for applications in the developing world. The nanoparticles are inexpensive, industrially produced carbon particles, and are not consumed in the steam generation process. The only input other than solar energy is water, which need not be sterilized prior to use.

Goal(s):
The goal of this project is to design and build a Solar Steam Sterilizer specifically for the processing of human excreta in resource-constrained locations.

Objectives: In Phase I we demonstrated a compact, standalone solar steam generator-driven autoclave capable of delivering high temperature steam (>130oC) for the sterilization of human waste. The prototype unit is capable of sterilizing a 14 liter volume of waste in 5 minutes (30 minute total cycling time). Both the short cycle time and the quality of the sterilized output “product” establish a new standard far above existing waste remediation methods.

Start and end date: end date 30 April 2013, final report due 15 June 2013
Grant type: GCE R7
Funding for this research currently ongoing? We are applying for Phase II funding

Research or implementation partners: Sanivation and EurekaSun

Links, further readings – results to date: We currently have one published article on Solar Steam:

Oara Neumann, Alexander S. Urban, Jared Day, Surbhi Lal, Peter Nordlander, and N. J. Halas, “Solar Vapor Generation enabled by nanoparticles”, ACS Nano 7, 42-49 (2013). pubs.acs.org/doi/abs/10.1021/nn304948h

Abstract:

Solar illumination of broadly absorbing metal or carbon nanoparticles dispersed in a liquid produces vapor without the requirement of heating the fluid volume. When particles are dispersed in water at ambient temperature, energy is directed primarily to vaporization of water into steam, with a much smaller fraction resulting in heating of the fluid. Sunlight-illuminated particles can also drive H2O–ethanol distillation, yielding fractions significantly richer in ethanol content than simple thermal distillation. These phenomena can also enable important compact solar applications such as sterilization of waste and surgical instruments in resource-poor locations.

This article was the top downloaded article of all ACS journal in the first three months it was posted online.

Please see also this poster which gives further results of our research (we presented this at the Reinvent the Toilet Fair last August in Seattle):

Kind regards,
Naomi

++++++++++++++

Naomi J. Halas
Stanley C. Moore Professor of Electrical and Computer Engineering
Professor of Physics and Astronomy
Professor of Chemistry
Professor of Bioengineering
Rice University
6100 Main St.
Houston, TX, USA

Re: On-site sanitation based on bio-additives and pit design (LSTH, UK and Tanzania, South Africa and Vietnam) - by: jensink

Fri, 03 May 2013 11:05:55 +0000

Dear Kim,

Sorry for the belated reply to answer your questions

I can see that you have partners in different countries; are you setting up pilots in communities in various socio-economic contexts?

Assuming we obtain the required funding we will be testing in urban, rural and humanitarian relief settings (Possible field sites are in India, Uganda and Ethiopia)

What is the general design and function of your system? What are the main components (type of toilet model, collection tank, etc.)? If you could share a photo of your system it would be great.

Detailed descriptions of the systems can be found online described in a report you can find at www.sanitationventures.com/_pdf/Mileston...vation-Final-Web.pdf

What are the requirements when it comes to operation and maintenance?

We don't know exactly yet but we anticipate it will not be high - removal of some vermicompost occasionally

Do you have any results regarding volume reduction of the material to estimate the frequency for emptying?

These are presented in the report above

Since your system is connected to a flush toilet; how do you manage excess water from the system after it passes the filtration bed? Do you promote reuse?

Not planning to at the moment, just allow it to infiltrate the soil

How do the tiger or earth worms cope with the high humidity in the biofilter?

So long as the drainage is good from their bedding layer they should be fine

best regards
Jeroen

Re: Reinvent the Toilet@lboro - Hydrothermal Carbonization - by: KimAndersson

Mon, 29 Apr 2013 12:41:58 +0000

Dear Sohail,
Thanks for your posting and for sharing information on your project, and also for the links to more reading on your research.

In the paper you presented at the Faecal Sludge Management Conference in Nov 2012, you mentioned that you were entering a phase where you will develop a full-scale toilet prototype to test based on the hydrothermal carbonization (HTC) process. Have you been able to develop this prototype, and if so, how is the initial testing going? You also mention that you had some challenges in front of you, one being the adaption of the system to a single household level, and another, achieving self-sufficiency from an energy point of view. Have you been able to make progress in relation to these challenges? I am also curios about the liquid residue that are resulting from your process. According to your paper, this liquid will first receive a treatment in an anaerobic digester before it safely can be disposed of. Will you be able to achieve this anaerobic digestion for a single household or are you also considering other configurations of your system? Another issue, is the nutrient content in the waste streams, how are you dealing with these to avoid nutrient leakage?

Best regards,
Kim Andersson

Black soldier fly for sanitation - by: muench

Sun, 28 Apr 2013 19:50:05 +0000

Dear all,

I obtained some further information from one of the researchers of this grant, Walter Gibson.
He told me that only the BioCycle has been progressed since Sep. 2012. The work is being done near Cape Town, at the AgriProtein experimental facilities.

Website: www.thebiocycle.com

The website contains some interesting videos, see e.g. this one which explains the idea behind using the Black Solider Fly (Using Black Soldier Flies to convert human waste to valuable commodities):

He also told me that they are are awaiting funding to do the field trials for the Tiger system. If they get it this will be done in India, Ethiopia and Uganda.
There is no work going on to his knowledge on the BSF toilet idea (within this grant). [BSF = Black Soldier Fly]

I have added some documents on results for this project here in the SuSanA library:
susana.org/lang-en/library/library?view=...p;type=2&id=1743
You can find:
1 - Literature review (May 2010)
2 - Poster by Ian Banks from Stockholm World Water Week in 2012 on black soldier fly
3 - Report on progress (Aug. 2012)
4 - Presentation on pit latrine fill; key lessons learnt (Sept. 2012)

Oh and black soldier fly research is also being done by Cecilia Lalander from the Swedish University of Agricultural Sciences, please see her presentation at the FSM-2 conference here:
www.susana.org/images/documents/07-cap-d...ander-slu-sweden.pdf
(this is not part of the same grant, but the same idea, as far as I can see)

Regards,
Elisabeth

P.S. Note: further discussions about the Black Solider Fly research is now in this separate thread:
forum.susana.org/forum/categories/91-pro...roductive-sanitation