SuSanA - Forum Kunena Site Syndication Mon, 22 Dec 2014 02:46:53 +0000 Kunena 1.6 SuSanA - Forum en-gb Re: Pathogen concentration in untreated fecal sludge - by: KeithBell
But I still like your point and believe we should also focus on how a toxic, polluted environment shifts flora in the wrong direction and out of balance.

Here's a 2014 study about organic pollutants in septic waste (not about pathogens):
Pharmaceuticals, perfluorosurfactants, and other organic wastewater compounds in public drinking water wells in a shallow sand and gravel aquifer.
Septic systems appear to be the primary source of OWCs in Cape Cod groundwater, although wastewater treatment plants and other sources were potential contributors to several wells.
Faecal sludge management Sun, 21 Dec 2014 17:19:41 +0000
Re: Pathogen concentration in untreated fecal sludge - by: SusannahSoilet
For a pathogen/parasite to successfully infect a new host through fecal sludge, it must surmount several steps:

1: gain contact

2: retain infectivity - i.e. have enough vitality to establish and procreate once contact is made

3: overcome the potential host's own defences - which are influenced by past exposure, diet, hygiene, genetics and concurrent medical conditions.

I would like to cite helminth control practices used in organic livestock farming here in the UK, which are:
Clean grazing (foraged feedstuffs) for susceptible individuals to reduce burden of exposure;
Optimum nutrition and avoidance of overcrowding;
Strategic use of anthelmintics, vaccines;
Breeding for resistance.

It might be worth considering that humans have evolved alongside a multitude of parasites and pathogens, and encountering some at low levels actually have beneficial impacts on protective gut microbiota and immune responses. In developing nations scenarios, there are usually individuals who appear remarkably healthy in the face of vast health challenges. Too clean can perhaps be damaging as too dirty!

Susannah Batstone, Soilet Systems.
Convinced that tiny things can solve big problems!]]>
Faecal sludge management Sun, 21 Dec 2014 07:15:29 +0000
Re: Pathogen concentration in untreated fecal sludge - by: TeamWTR
Blanca E. Jiménez C., Catalina Maya R. and Germán Salgado V. (2001).
The Elimination of Helminth Ova, Fecal Coliforms, Salmonella and Protozoan Cyst by Various Physicochemical Processes in Wastewater and Sludge. Water Science and Technology.43 (12): 179-182. **Indexed in the MEDLINE database.

Jiménez, C. Maya, E. Sánchez, A. Romero, L. Lira and J. A. Barrios (2002).
Comparison of the Quantity and Quality of the Microbiological Content of Sludge In Countries with Low and High Content of Pathogens. IWA Journal Water Science and Technology. 46 (10): 17-24

Diaz-Avelar J., Barrios J.A., Maya C. and Jiménez B. (2004)
Reduction of Helminths Ova and Faecal Coliforms in Biological Sludge using a Biodegradable Acid (PAA). Water Environmental Management, 7:299- 306.

Jiménez B., Mendez J., Barrios J., Salgado G. and Sheinbaum C. (2004)
Characterization and Evaluation of Potential Reuse Options for Wastewater Sludge and Combined Sewer Systems in Mexico. Water Science and Technology, 49(10):171-178. ISSN: 0273-1223.

Jiménez B., Barrios J., Mendez J. and Diaz J. (2004)
Sustainable Management of Sludge in Developing Countries. Water Science and Technology, 49(10):251-258. ISSN: 0273-1223.

Best regards,

Faecal sludge management Fri, 19 Dec 2014 19:52:14 +0000
Re: Pathogen concentration in untreated fecal sludge - by: JKMakowka Of course there are some opportunistic pathogens that are wide spread in healthy populations, but those are probably not such a huge concern in most cases.

Measuring fecal coliforms only makes sense as a measure of treatment efficiency as they are by themselves (mostly) non pathogenic.

Maybe you could explain what the actual purpose of knowing/measuring those pathogens would be for you?]]>
Faecal sludge management Fri, 19 Dec 2014 19:36:20 +0000
Re: Pathogen concentration in untreated fecal sludge - by: TeamWTR
We have a little information on raw untreated sludges. Maybe you can use some of it. Here is a table with the information we have.

Hope it is useful, best of luck.

Faecal sludge management Fri, 19 Dec 2014 19:21:02 +0000
Pathogen concentration in untreated fecal sludge - by: sharadaprasad
I am trying to estimate the concentration of pathogens in untreated (fresh from the septic tank) septage. I could find papers that estimate the pathogen concentration in treated sludge but not in fresh septage. Many papers acknowledge the lack of data related to the biological characteristics of fecal sludge (data related to physical and chemical characteristics are relatively easier to find)

Studies of Heinss et al (1994 and 1998) provide a wide range for Helminth egg concentration in fecal sludge. And multiple studies in African slums list - NWSC (National Water and Sewerage Corporation) (2008). Kampala Sanitation Program (KSP) - Feasibility study for sanitation in Kampala, Uganda - as the source of estimating fecal coliform concentration.

I was wondering if you have come across any other papers that estimate the concentration of any of the following pathogens in untreated septage.

  • Protozoan parasites
  • Enteric viruses ( Enteroviruses, Rotavirus, Adenovirus, or Norovirus)
  • Enteric bacteria (Salmonella or shigella)

Haas et al (2014 2nd ed) lists the concentration of all the above pathogens in human feces. But I am not sure whether we can estimate the concentration in fecal sludge based on the concentration in feces (die-off rates are not easy to assume).

I searched through SuSanA posts and I could not find any information related to concentration of protozoa, viruses or enteric bacteria.

Any pointers are highly appreciated. Thanks.

Faecal sludge management Fri, 19 Dec 2014 10:38:58 +0000
Re: Questions on Faecal Sludge Management (calorific value of faecal sludge using bomb calorimeter), Bangladesh - by: BJWard
We recently published a paper where we measured the calorific value of chars made from fecal sludge, and used the ASTM method D2015 (Standard Test Method for Gross Calorific Value of Solid Fuel by the Adiabatic Bomb Calorimeter). The ASTM method is here:

I've also attached the paper so that you can take a look at the methods section.

To answer your question about time limit for conducting the experiment - if you're collecting relatively fresh sludge, I would recommend refrigerating or freezing it until you're ready to analyze it. We have seen fresh sludges degrading pretty rapidly when not stored at cool temperatures, and have noticed that the energy content can decrease significantly as the material continues to degrade. So, for practical use in your project, if you're taking multiple measurements of one type of fecal sludge, either do them all in the same day or two, or make sure you keep them frozen or refrigerated between runs in the calorimeter.

Good luck!
Faecal sludge management Thu, 18 Dec 2014 21:44:29 +0000
Re: Questions on Faecal Sludge Management - by: ChrisBuckley I suggest you use the ASTM technique for the calorific value.

In addition determine (1) the dry solids mass at 105 Deg C (and thus moisture content); (2) the volatile solids content by igniting in a muffle furnace at about 500 Deg C, this will also yield the ash content; (3) the soluble ash content, by washing out the soluble components.

You may also wish to measure the charring temperature and to produce bio char
The opportunities for biochar are: yield, ash content, surface area.

Faecal sludge management Wed, 17 Dec 2014 06:20:06 +0000
Re: Questions on Faecal Sludge Management - by: Progga And about other parameters, as my work is in small scale I may not have the chance to determine other parameters described there for 'dried' sludge apart from COD. So I need some suggestions on that.]]> Faecal sludge management Tue, 16 Dec 2014 17:41:25 +0000 Re: Questions on Faecal Sludge Management - by: joeturner]]> Faecal sludge management Tue, 16 Dec 2014 14:57:04 +0000 Questions on Faecal Sludge Management (calorific value of faecal sludge using bomb calorimeter), Bangladesh - by: Progga Faecal sludge management Tue, 16 Dec 2014 14:31:46 +0000 Re: LaDePa is a faecal sludge pelletising machine in eThekwini (Durban) - by: SeptienS
I have posted a couple of videos from LaDePa process plant and its laboratory pilot.

1 - The LaDePa (Latrine Dehydrtation Pasteurization) machine has been installed in Tongaat wastewater treatment plant, located in the eThekwini municipality (Durban, South Africa), in order to process feacal sludge collected from ventilated improved pit latrines. The product target consist in dried and pasteurized pellets which can be used in agriculture or as a biofuel.

2 - The laboratory scale LaDePa, located in the experimental facilities from the Pollution Research Group, in the University of KwaZulu-Natal (Durban, South Africa), is the prototype of a full scale machine in Tongaat wastewater treatment plant, for the drying and pasteurization of faecal slugde from improved pit latrines. Its objectives are to better understand the phenomenology and optimize the process, and to evaluate the product for agriculture use or as a biofuel.

If you have comments about the videos, please let me know.

I wish you a lovely day.

Best regards,
Dr. Santiago Septien Stringel]]>
Faecal sludge management Thu, 11 Dec 2014 14:20:30 +0000
Re: Simple Solar Sludge Drying During the Monsoon (experience in Bangladesh) - by: christoph
Very interesting approach. I did some rough calcs:

600 – 900 l/batch with (assumption of 30 kg/m³ (3%)) is 18-27 kg/batch. Assuming 15 days for one cycle it would be a 100 – 150 kg TS/m²,a. As this would be close to normal drying beds the initial TS and final TS after 10 days would be interesting.
Could you provide some more details (or may be you did not have the chance to collect these data).

  • TS content raw and after drying
  • Did you do helminth eggs?
  • Did you measure temperature in the greenhouse and in the sludge?
  • I was wondering about the comment that raking is not efficient for pathogens – I would expect better drying = less pathogens – could you comment a bit more on that (how many samples have you been able to do – is it more an observation/guess or is it proven data?)
  • I was wondering as well that you wrote first drying than “cooking”. I would have expected first “cooking”, than drying? And cooking for me means hot  hot means no or much less pathogens. Why did you have though only 99% pathogen removal (which is 2 logs)
  • Did you try out how the sludge behaves if you try to come to really high drying (as to be able to be burned? As mentioned in the EAWAG video?)

Thank you

Faecal sludge management Sat, 06 Dec 2014 13:39:55 +0000
Re: Simple Solar Sludge Drying During the Monsoon (experience in Bangladesh) - by: CeliaWay
The beds were sized to treat the contents of an 'average' pit latrine i.e. 600-900L (15-20cm depth of sludge on the 1.5 x 3m drying bed). The idea being that one pit's contents could be treated at a time, and it could be used sequentially by a group of households.

Layering wet sludge on top of dry would not be a good idea - suggest as with peppercorns, it's a batch process!

Glad our work is of interest,

Faecal sludge management Fri, 05 Dec 2014 17:05:43 +0000
Re: Simple Solar Sludge Drying During the Monsoon (experience in Bangladesh) - by: denniskl
Very useful information Celia - do you have specifications for bed sizes by expected volumes etc?

And in terms of processing, capital expenditure, set up etc, can you simply add daily FS layer upon layer or do you need to have multiple beds for different processing days?

(As a non FS example, for solar drying peppercorns in rural low resource locations, you pick today and keep that days product in one pile, then move it along a "conveyor system" - well another mat:) and then tomorrow's crop, you put in another pile for drying, so you don't get uneven drying and you can easily be aware of where each pile is at etc.

Does that matter with FS - if you keep piling the next days FS on top, do you just keep reintroducing pathogens?

Or are we talking some form of daily separation?]]>
Faecal sludge management Thu, 04 Dec 2014 23:33:49 +0000