Dear Ajit,

thanks for your reply and again I got lots of information I have to chew and questions rise up:

what do you mean when write:
"One needs to note that worms in vermi composting process need the bio- matter in semi cooked form and never can raw matter be fed to them".

I am not into vermicomposting but did quite a bit of composting of dung, veggie left overs and so on. It always worked well without any "precooking". But before the worms crawled into it, the compost heated up over 50 degree Celsius because we wanted it to kill the weed seeds. This we steered by mixing, airing and watering. Are we talking about the same process? Or are talking about a complete anaerobic process like (thermophil) biogasification?
And do these worms like the same range of temperature (10-30 degree C)?

If I come to India one day..... your plant would be a of high interest for me. But I still have to save money....

Beste wishes,
Heiner

Dear Heiner.

I am thrilled to note your enthusiasm, ie you wish to connect sanitation with plant production.

Its possible, here we look at 2 types of scenario ie one in which human sludges are released into open in dry solid form and another in which each volume of human faeces is mixed with toilet flush water ie 1: 5 ltr to 15 ltr. in wc mode.

It is the former which is tough to tackle/ digest or get it composted to usable manure form ready for agri farm use.

When these human sludges are ad-mixed with bio mass ex market , agri or house hold waste, or cattle dung, then it is easily composted to manure form.

One needs to note that worms in vermi composting process need the bio- matter in semi cooked form and never can raw matter be fed to them.

In the raw stage, it is anaerobic and a bit warm too and not congenial for worms to survive and work to digest the resource matter.

When you observe a pit in which vermi composting is progressed, it will be seen that worms after consuming all the nutrient matter go over to newer ( raw) portion in the vermi bed.
The process happens for 2 to 3 weeks.

It is when, all worms are gone, its a sign to say that now compost is nearly ready for last process of curing and maturing done in about 2 - 3 days.

Now ready to use compost is removed and kept dried bagged for future use.

In the other STP having waste water with sewage and sullage, one needs to use a STP with process.

In all the process, when maintainance cleaning is done, the sludges removed are subjected to vermi composting.
Here too the process is same as explained done in sewage sludge composting process as explained earlier.

Lesser hardy worms may be used in this wet process.

As indicated earlier, worms are also a saleable commodity as used for catching fish in hooks Etc..

Well wishes..
Prof Ajit Seshadri . Chennai India .

Dear Elisabeth,

you are right (of course...), IFOAM accepts "human fertilizer" under special circumstances:
www.ifoam.bio/sites/default/files/ifoam_norms_july_2014_t.pdf

"Source separated human excrement"
Only in compliance with requirement 4.4.5.

4.4.5 Fertility amendments in Appendix 2 that are rapidly available to the plants are exceptionally allowed only as a necessary complement when other fertility building techniques have been applied and are insufficient.

4.4.6 Human excrement shall be handled in a way that reduces risk of pathogens and parasites and shall not be applied within six months of the harvest of annual crops for human consumption with edible portions in contact with the soil.

And page 17 and 18 of this paper: www.fibl.org/fileadmin/documents/de/taet...keitsbericht2018.pdf
show they even work on our topic in concern to EU BIO Standards...... (sorry, just in german). But the actual BIOLAND and DEMETER standards in Germany do not allow any of these substances.

So your multi-barrier approach is not to far away from the ideas of IFOAM. What makes me quite happy. About the national and international requirements you know much more than I do.
The wikipedia article about reuse of excreta is great and comprehensive. You worked on it? Should be spread to pupils as well as politicians, students, environmentalists, journalists a.s.o.

Funny, in Harare we worked GAP certification as a requirement for export too. And named the points for the processing plant in planning. Here the standards for toilets hand washing utilities and so on had to be discussed. This became very aware a few years back when contaminated sprouts from Egypt (?) caused the death of some older/sick people in Germany.
But there are 80 million left...and I don't like them all anyway....

My broad question about a visit of a plant "somewhere in the world".... I am not a scientist and have to look and smell and touch things. This haptic approach is perhaps typical for my profession. I worked for a little start-up (the guys were on this platform too, years back) and cleaned so called compost toilets on festivals and other events. I fixed and transported this toilets and got a good feeling about the over all efficiency . When I now ask for a visit of a "plant" or little test side, it is just to learn more and hopefully get in contact with some farmers who use the stuff. Vermifiltration sounds very interesting to me but also biogasification , composting and irrigation are of interest. The trouble starts when you "do" it and thats where I was placed in my career as most of you on this platform.

And I know, I am demanding... This thing has to be right next to a beach where I can scratch my belly in the sun after the visit. I give it a try, at least...

Since I am not a scientist I won't be able to give substantial input to wikipedia. But obviously you do. So if you have any questions about agriculture just let me know and I will you help if I can.

Have a nice day;
Heiner

Dear Saintie,

thanks very much for your answer. It helps me to understand the speed of the movement.....
AUS or California would be great to visit but because of my small private budget not the first choice. "Hundred of tons" of worm cast (is it the excreta?) make me smile as farmer as you can imagine. I loved my worms in the organic fields. They were the visible basic of our success.
AUS and California are in need of water and they are rich countries which can do some research and development. Looking at high developed plants can be dangerous when you try to break it down to more simple solutions but it is not impossible.
Israel and more and more Spain use lots of wastewater as far as I know. Im not to keen to visit Israel for different reasons but it seems as if they have the leadership in big scale reuse. And from there I read the simple reason for wastewater reuse: it is much cheaper than desalination.
Part of our ecological footprint is the overuse of groundwater. And as I just learned in Simbabwe things are not even in their mind. Lots of boreholes are drilled and your are allowed to do so, there are no limits. All you have to do is registrate them when the water pours. This is not really environment caring policy. Result: more and more boreholes run out of water in the dry season. Taking this example I think the situation is much worse than we think.
That you sanitation guys and the companies you work for do not look far into the plant production world and the food supply is understandable. But we have to build bridges to understand the whole. On my farms lots of biologists were running around looking for all kinds of species. In contact with those people I learned a lot about the wildlife in my fields and how I harmed them by accident. Though we found little solutions here and there what made us all happy.
So my goal for the next...years is to build a little bridge from sanitation to plant production , point on the necessary loops and the barriers which prevent their closing. Lucky wise other people are working on the endocrine disruptors and develop alternative products to the benefit of nature and environment.

Cheers and lovely day,

Heiner

Dear SuSanA Members.
And those who are keen on Developmental projects on WASH Sector,
Indian Government is seeking innovations in this sector and a Press cutting is enclosed.
The scheme talks about a Toilet Board Coalition aspiring to do projects on Business model of WASH Etc.
A lot desires to be done at grass root level and ground work in earnest.
Well wishes to Members.

Hi Heiner,

I love your forum posts. It is so refreshing to read from an "outsider" who is crossing into another sector (from agriculture/organic farming to sanitation in developing countries). We need more people like you!

You said: "But this is against the rules of IFOAM and so it remained off topic." Could you clarify a bit more what you mean there? Perhaps with a link to the relevant page? Does IFOAM say explicitly: "you shall not use any human excreta derived fertiliser in organic farming?".

Recently, I added something similar to the Wikipedia article on Good Agricultural Practice (GAP) based on a new paper by Alison Parker. I added this sentence:

The use of sewage sludge is currently not allowed on GAP-certified farms of horticultural crops (though it is unclear whether this includes compost derived from sewage sludge and other human excreta derived fertilizers).[2]

(see here: en.wikipedia.org/wiki/Good_agricultural_practice#Soil and here: forum.susana.org/forum/?view=topic&catid...253&start=1000#28441)

(Do you have time to help me improve the Wikipedia articles on GAP and IFOAM in your spare time?)

Speaking of Wikipedia, have you read the article on reuse of excreta? It's very good and should give you an overview on all the different aspects of reuse of excreta in various forms (I was involved in writing much of it):
en.wikipedia.org/wiki/Reuse_of_excreta

Regarding your question on where to go to see reuse in practice: I think your question is too broad... There are reuse activities in pretty much every country. Maybe best if you specify which country or countries you want to visit and then we search for people and projects to visit. When you say "plant" do you mean a large-scale centralised wastewater treatment plant? Or do you mean vermifiltration plants in particular? If it's treated wastewater reuse in general (very common) then this is a good starting point: en.wikipedia.org/wiki/Reclaimed_water

Regards,
Elisabeth

Hi Henier, Your question is simple but difficult to answer. This is because that many companies that use this technology primary goal is to treat the wastewater to an acceptable standard to minimise impact on the local water course and nothing else. The companies that provide the technology are not around when the worm casts are removed so cannot comment on where it might end up. However it is a fair expectation that since sewage sludge is routinely used in agriculture, the use of the worm casts in agriculture would be an expected outlet. One Australian company (now bought over) used to treat approx 100t of sludge a week, treat it using vermicomposting technology and sell the worm casts. Great business as water companies routinely pay for sludge treatment few if any can get any return on the treated sludge products (mostly give it away for free). This company did as worm casts are a high value item in the right market.

As for the treated effluent re-use it would depend on the setting. Most companies using this technology only want to meet environmental compliance goals. For irrigation the end user must be in a water stressed area and have a need for re-use. The irrigation demand needs to be right on the doorstep of the wastewater plant as pumping water costs money. Add to that the irrigation requires a bigger capital spend and subsequently requires larger wastewater flows for the sums to add up. Finding large scale plants with these constraints, attributes and goals are even rarer. I am aware of a plant in South America where the final effluent is used as dust suppression on the roads. There is also a plant in California which does re-use the final effluent for irrigation to minimise the water abstraction required by the business.

Saying all of that I have worked in the water industry for over 25 years and I am struggling to name a conventional wastewater plant that uses final effluent for irrigation. It is still seen as a novel idea. However as more areas/countries wake up the lack of local water availability then in future this will start to become the norm, right now we are not quite there. That said I for one will not stop promoting the Circular Economy benefits from this technology, along with the lower capital required, lower operational costs etc.

Hi Hajo,

I missed your last reply (12. Oct.)when I spend some weeks in Harare and had little online time there, not to mention power. My mission in Harare had the focus on organic farming and all I could do was to raise the topic of nutrient loops and wastewater use. But this is against the rules of IFOAM and so it remained off topic. But Zim has to care for water and nutrients but they people struggle for their daily life and the authorities.... I really don't know...

In my dream about the future sustainable agriculture we leave the restrictions of organic farming as well as the destroying practises most conventional farmers do on their farm.
I am on this platform to meet people like you who make the human excreta, at least partly, ready for use on the fields. And/or who make wastewater ready for irrigation. The growing cities will steal the groundwater and we farmers will never be able to win the competition. So we simply have to live with the water leaving the cities.

And it is not quite true: "Nobody considered that this technology (WC) deprives agriculture of nutrients...". At that time Justus von Liebig pointed that out, but the majority did not listen...
A leading scientist of the organic movement estimated a yield increase of 20-30% when we close the loop. And it is somewhat funny when the majority of organic farmers claim they work with nutrient cycles because they use the manure of their livestock. And when you ask them what would you do if more and more young people become vegans (okay, an overestimated assumption) they look a bit silly.

But there is a long way to go, of course. Nevertheless we farmers have to discuss it as responsible persons for food supply. From you guys here I want products for my food production: as good as possible, as cheap as possible....but not perfect and different in different countries and climate zones.

When I read the first letters here in this forum I got the feeling things are running well and lots of plants are working all over the world. Producing fertiliser and irrigation water on a large scale. Obviously this is not true as I realise now.
But: Is there anybody here who can name me a running plant (no matter what type) which uses the sludge (dried, composted,...vermicompost, however) in agriculture or horticulture and/or uses the wastewater for irrigation?
I would like to combine my next holidays with a visit of such place, if possible.

Every suggestion welcome

Cheers,
Heiner

Hi Hajo,
thanks for your welcome.

wherever I go now I will not be in the situation to choose what I want. I will bump into a situation and discuss ideas how to shift things to the better side. With the knowledge I have my preferred solution as a farmer would be to have urine and excretes separated. Urin as a fertiliser and excretes for composting and soil improvement or for biogas.
But irrigation is one of my other topics and there will be connections. Local food security is my job.
But in case of Harare I know more in 9 days.
Good to know an experienced man like you is not too far away. Thats the expected good thing of this forum!

I shout if I need help or if there are chances for you to get involved.

see you

Dear Elisabeth,

thanks very much for welcome and your advices. I go on reading now....and thats a lot
Didn't know Peter Morgan is still acting and lives in Harare. But he was mentioned to me by Ralf Otterpohl too.

As a farmer I hope to meet some people here who are on the applying side of the whole "business". I would like to be involved in the difficulties using the fertiliser and/ or the wastewater. Since I will not establish and construct any technology lots of info,action here are beyond possibilities. But, as I wrote, I have some Ideas to integrate the substrates into food production even if they meet not all standards.

But first of all I have to arrive in Harare und see whats going on there. My informations up to now are not very sunny. And if there are chances to discuss our ideas of sustainable sanitation and sustainable agriculture as a package....that would be great and I give a yell!

Right now time slips through my fingers but we stay in contact!

Regards,
Heiner

welcome in the loop, Heiner..

To close the loops, we have to get away from sanitation systems which use (too much) water, flushing our shit and pouring the effluent into rivers, lakes and oceans. Why? Very well described here !

I am currently trying to promote vermi-culture, using worms digesting human excreta, producing humus, and the more or hopefully less flush water brought back onto soil. For more information read our SuSanA thread .

ciao
Hajo

Dear Heiner,
A warm welcome to the Forum! You have come to the right place for these topics.
Just some quick feedback:
- If you are going to Harare, are you going to meet Peter Morgan? I hope you do. For an intro, see his dozens of publications in the SuSanA library... He is amazing.
- Have you already read all the key publications on the topic of resource recovery and "productive sanitation" etc.? If not, please head to the SuSanA library and tick the filters on "reuse" or tick the filter "Zimbabwe". If you have any difficulties there, do let me know. www.susana.org/en/knowledge-hub/resource...publications/library
- If possible, can you make your questions more specific? Then it is easier for people to help you and enter into a discussion.
- Also check which other SuSanA partner organisations are in Zimbabwe. I used the country filter for our partner database and it gave me these results: www.susana.org/en/community/partners/lis...&vbl_20%5B589%5D=589 (I was hoping to see more local NGOs, but not so).

I am so curious to hear how things are going in Zimbabwe by the way... Robert Mugabe's recent death for some reason didn't get much coverage in international media.

Regards,
Elisabeth