Hi Hajo,
I'd consider the appropriate overarching term to be "vermitechnology" rather than "vermicomposting".
My view is that the term "vermicomposting" is not relevant for human waste because the carrier (water) is of far more importance than the "compost" (humus or residual solids), especially in terms of agricultural applications. In domestic wastewater systems most of the nutrients are carried in the post-vermi-effluent water. The liquid effluent from vermifiltration is plant food. Even the nitrogen can be retained in the liquid fraction (a good thing for application to land, a bad thing for application to waterways). The solids, on the other hand, are few and far between and removal frequency is low. Their only use is as soil conditioner. Vermicomposting, on the other hand, is (in my view) a process that can be applied to fresh organic solid waste such as plant-based biomass and even sewage sludge, but the focus is on the solids as the raw ingredient and end product. One could say that the primary vermi-digester is indeed "vermicomposting", but I see it as a filter still, the worms convert solid waste into filter media.

Perhaps the most important aspect for the sanitation community to consider is the biological safety of waste re-use systems. Cholera, helminths, giardia etc spring to mind. What have the academics been doing for the last two decades... still no time period for digested, rested humus to be be helminth free. No simple equations for vermifilter capacity per user and recirculation frequency per unit pathogen reduction. Why have the institutions apparently not even heard about the technology let alone begun asking useful or relevant research questions?
cheers
Dean

dear all,

I can imagine that the question in this topic does not attract a lot of attention as it seems being purely administrative. Just to bring it back to the top of the list of recent topics, I want drawing your attention to our statistics where 'vermicomposting' appears each twice (2x) among the Top 10 of 'Most Active Topics' and 'Most Viewed Topics'  of All Times.

Does this not prove the case that the topic 'vermicomposting' deserves its own Sub-category?

ciao
Hajo

Dear all,

when I opened this topic, my intention was to have all these interesting discussions in one place. I remember having discussed with Dean about the terms of vermi ...    , but where was it, and when?

I agree that the terms are not yet definite, probably also because too few people were interested yet in vermi ....

The processes are easy, defining the right terms is not:
Either FS from pit latrines, septage from septic tanks or sewage from sewers are fed on a bed populated with worms. At this stage suspended solids from the applied excreta are separated/filtered out and are digested by the worms and turned into worm cast (humus) which has to be harvested as it builds up. The water trickles through and is collected for the the next process.

The Wikipedia article on Vermicompost calls the mixture of organic material, bedding material and wormcast as 'vermicompost'. Thus in sanitation it would be the mixture of faeces, bedding material and wormcast being called vermicompost. I don't like it, because 'compost' has for me a positive overtone. Maybe I would call the vermicast alone as vermicompost?!

In the Wikipedia article on Vermifilter, the first stage of processing by worms is called vermifilter or vermidigester (lumbrifilter seems to be a patented name). Basically it is the same process as described before: separating solids from fluids with solids being digested by the worms and turned into wormcast.

Thus, we could call the first stage 'vermifilter' as well, as it separates solids and fluids. We can call it 'vermidigester' as the worms turn the solids to wormcast (humus). We can call it 'vermicomposter' as it produces nutrient-rich organic fertilizer and soil conditioner.

In a second (and third, and fourth) stage the effluent from the 'vermidigester' is fed again into a 'vermifilter'. This filter will assist removing dissolved solids, pathogens and will enrich the effluent with nutrients from the worms' poo and pee. This filter is not flat and wide but high and small, firstly, to extend the contact time between filter media, micro-organisms, worms and effluent, secondly, to ensure aeration of the filter. This surely can be called a 'vermifilter'. Sequences of filter runs of the effluent will improve its quality as irrigation water.

I tended to call the whole process and technology 'vermiculture' until I learned from wikipedia that this term is reserved for rearing worms. Now, what shall we call it considering above explanations. Dean, I hope they are correct, you taught me for so many months, by now I should know. I then tended to call the whole technology 'vermicomposting' (producing nutrient-rich organic fertilizer and soil conditioner), the first step being a 'vermidigester' and the second (third, fourth) a 'vermifilter'.

But I don't mind calling it differently as long we agree, it is not misleading, and we finally start discussing how to  promote the technology under the new sub-category 'vermi ....'.

ciao
Hajo

Before going into it further, could we please clarify the terms again. In my mind vermicomposting is for solid material (similar to composting) whereas vermifilter is for liquid material. And the overarching term for both is what? Vermifilters?

Wikipedia has it as follows (if we don't like it, it's up to us to change it, using reliable references):

• Vermicomposting:  en.wikipedia.org/wiki/Vermicompost 
• Vermifilter:  en.wikipedia.org/wiki/Vermifilter 

Regards,
Elisabeth

Hi all,

as a farmer I agree to 100% we have to discuss and develop the resource recovery more intensively than we did in the past. The topic is well known since "ages" as you , Hajo, showed e.g. with this document from 1993:



But I can tell you on top a German scientist, Justus von Liebig (a chemist), said in the 19th century in his chemical letters (No. 47) "....there is no doubt that the export of food from the land to the city and  no return of excretas will cause a lack in fertility and has to be refilled with guano and other mined minerals......"

Very up to date, the same sad story:

www.globalagriculture.org/fileadmin/file...ationFoodSystems.pdf   

I read this report of some 40 scientists who related very much on the SDGs. I got the report very early and was asked for feedback. I did and asked them: how come, when you talk about the sustainable agriculture of the future, there is only one author out of 40 who mentions the nutrient circle (closing the loop) and all the others not?   I made then a calculation of my country, where 450 000 t of nitrogen end up in the sewage plants per year. Of this roundabout 80% is burnt (destroyed) and 15-20% flushed to the marine system.
Since I am not a Prof. of anything they just ignored my feedback even though they asked for one....

We, here in the forum, got all the scientific arguments on our side. But: we dig in the dirt. It is fine to care for hygienic standards it is less fine to look after pee and poo, I guess. The alternative  "clean" minerals, mined somewhere in the world have the better reputation and because of that we have the overshot day in May.......

To me vermifiltration/vermicomposting and BSFs are on the same level. Both close the loop. Climate, temperature and the medium (dry or wet) make the difference. As a farmer I get feed, enriched irrigation water or organic fertilizer back . That is what we need to feed the world in a sustainable way. But I am not the categorizer......

Last point: IFOAM. You, Hajo, once stated they should be our natural allies. As I wrote you before: they care for a superior "very clean" product and are only in theory interested in closing the loop. Two years back I wrote to the former president of ifoam (Bernward Geier) after he published a new book...that I missed the importance of the ....nutrient cycle in his book. And he agreed and said it is a good idea for an panel on the next "BIOFACH Nürnberg". I said fine I am looking forward to it! There never ever was a panel.....

I live right next to the IFOAM headquarter and if you guys think it makes sense to contact them again as a fast growing forum or any other initiative, I will assist you if I can.

But in general I think we should look for other allies. WHO, FAO, WFP if we look from a big scale? Or just work local and look different in various countries and try whatever is possible.

Have a successful day,
Heiner

 

Hi

I see vermicomposting on the same level as black-soldier-fly because we have to understand that vermicomposting produces usable products (humus, irrigation water) which we MUST use if we want to close the loop. All land living creatures put their poo and pee  on the soil so that the nutrients can be reused by the soil growing their food. ONLY the humans feed their excreta into rivers, where they are not needed but even are harmful. We have to understand that human excreta have also to go back to the soil. We need this approach (by vermicomposting or other technologies) to find sustainable processes for human excreta and to improve agriculture.  

Putting vermicomposting on the same level as BSF in the forum, I want to ensure that the future discussion of vermicomposting is NOT seeing it as a treatment system only but as a possible technology closing the loop. It is probably not yet there but our discussion should bring it there!  And we have to materialise that ‘sustainable sanitation’ is not only the UDDT in Elisabeth’s house and the vermicomposter under Dean’s verandah but that we have to develop the technologies to a level where centralised and des-centralised sewage systems, FS treatment works and on-site sanitation can use the technology commercially. 

Ciao
Hajo

Hi,
My response is just about your suggestion of re-arranging the sub-categories (not about the technology and perceptions around it): Interesting suggestion. 
 
I am happy to review the different options and have a good, thorough brainstorm about it. My first reaction is that yes it could be beefed up in the green category (reuse) but I wouldn’t remove it completely from the blue category (technologies). The categories follow broadly the sanitation chain, i.e. user interface, treatment, reuse, management.

According to your logic, also UDDTs and composting toilets would have to be moved from the blue category to the green one?
 
I think the Black-soldier fly technology is in the green category because its main aim is to produce a usable project (larvae). I am just not sure if the same could be said for vermifilters. I see it more as a treatment system with a potentially useful by-product (water and fertiliser); this would apply equally to other technologies (composting, decentralised wastewater treatment, UDDTs (those can be with or without the aim of reuse))….

Those are just some quick reactions. It needs further thought but I just wanted to
send a quick reply back already tonight.
 
Elisabeth

Dear hajo

I very interest  in vermicomposting and which you have been writing  in additions all you have mentioned in your post I would like adding entrepreneurial  developments  capacities food securities not only in Africa but also in the Asia , vermicomposting  has  great option for green zone increasing and climate changing mitigation. 

Thank you for your applied scientific  information


Regards
Mohammad 

Dear all, dear Heiner, dear Dean,

 You may have noticed on the forum that I got quite interested in vermicomposting over the last years. I consider it could be a very useful sanitation technology in Africa. But I also notice that it seems not being attractive for users, utility managers, administrators, politicians, donors and financiers. This may be because it so cheap and so low-tec: what doesn’t need machines and doesn’t cost, cannot have a value.
 
But I also observed another aspect which may hinder the adoption of vermicomposting technology at larger scale. The connection between sanitation through vermicomposting and organic agriculture seems not being recognised or accepted at large. Not recognised by sanitation experts who look at BOD and COD reduction which will allow to feed the effluent from a WWTP to the next river and not knowing about the resources which are wasted there. Not accepted by those who are aware of the nutritional value of human excreta but not knowing how to treat possible contamination and fearing the rejection by potential users and consumers.

I had a communication recently with an international NGO and they reported about their projects in Asia and East Africa promoting organic agriculture, even using vermicompost, but only made from organic kitchen waste and cattle manure not from human excreta. My attempt to discuss with them vermicomposting of excreta was left unanswered. Further, there was a week-long workshop in Kigali about organic agriculture. One participant who has a business in producing compost from waste, confirmed to me that he was asked not to mention that he also does vermicomposting from human excreta. He actually builds Tiger Toilets. He also confirmed that the users of the toilets show little interest in the reuse of the products, unless he himself harvests the worms and the worm cast and pays them for the worms. This shows the need for service chains in on-site sanitation. Generally people don’t want to care about their remains which is understandable. 

Now, in order to promote the collaboration between sanitation and agriculture, I want to propose that we put all discussions about vermicomposting under the Forum category ‘Resource Recovery’. Doing so, I want to emphasize that vermicomposting is not (only) a technology to deal with human waste, but that this technology is specifically used to produce resources for (organic)agriculture. I want to attract more agriculture experts (and not only Heiner) to discuss with sanitation experts, how vermicomposting must be improved making it a valuable contribution to agriculture. We must discuss qualities, quantities, service chains, economics. I once read that reuse of human excreta must be discussed starting from the market: who needs what, in what quality, in which quantities and when at what price. The answers will determine the (commercial) value chain. 

For this purpose, I want vermicomposting to appear as prominent as possible in the forum. Thus, I would propose a new Sub-Category ‘Vermicomposting’ under ‘Resource Recovery’. Similar as the black-soldier-fly technology has its own sub-category there ( Production of insect biomass from excreta or organic waste). The topic ‘vermicomposting’ should not be hidden too deep in the contents structure. We need agriculture experts finding it easily if we want to attract them discussing on this sanitation forum.

Further, I would propose moving all threads which discussed ‘vermicomposting’ exclusively from previous locations to this new sub-category:

• Vermifilters for blackwater treatment, "worm toilets", "Tiger worm toilet" (7  topics)        
• Vermifilters (or vermi-digesters) (11 topics)
• Vermicomposting            4 topics

 What do you think?
Ciao
Hajo