Dear Detlef!

Thanks a lot for this very helpful information!

Thanks a lot for posting about this here and also open-sourcing these designs.

I think this is a really important step in breaking a very common and highly problematic chicken-egg sort of issue that you can find in many countries and projects. i.e people shy away from planning works that require difficult to import components, which in turn leads to total unavailability of those components on the general market and vise versa.

The next step would be for some possible early adopters like BORDA or other NGOs to plan a project that involves known to be innovative local producers such as Cresttank in Uganda and get a local production running (mainly by ordering a sufficiently high quantity to justify the expenses in tooling for these companies).

Once local production is in place, supply driven market take-up is commonly seen if there is a general need for such products.

Open Source: “Simple” but professional automated gravity distribution to CW for pre-treated sewage by “floating Valves” & by “self-priming Siphon’s” for raw sewage, made by DIY?!

Dear Colleagues,

This is a continuation to past forum posts on the subject “floating Valves & Siphon’s”:
#21130 and #18097

forum.susana.org/229-dewats-decentralise...ystem?start=12#21130
and
forum.susana.org/229-dewats-decentralise...ystem?start=12#18097


Here is a big question to you all, as an introduction & possible mind setting:

What is in your opinion helpful for the general goal of “sustainable sanitation” by SuSanA and others, high-tech "proprietary & patent driven technology by and for few" (often susceptible racehorses) or more towards low-tech “non-proprietary” technology, "Open Source" (Creative Commons 4.0) by and for many (often sturdy workhorses)? In other words, what is creating more profitable businesses for many, the priority of personal gain at the expense of public benefit or vis-à-vis?

Kindly keep in mind the following text is just our/my own subjective and informal view on engineering issues and not necessary a view of BORDA e.V., neither they are responsible about at all.


History:

The following is based on past engineering exercises for a vertical flow constructed wetland (CW) ~1,200 p.e. project for BORDA e.V. from Bremen in Germany. A floating valve been used after an ABR pre-treatment for a very flat new residential area of Dar es salam in Tanzania. I regret to say, we been forced to start our own engineering, because we could not convince in 2016, the company ALISTEP in France, to sale to BORDA e.V. direct or via us one unit of their very well designed and elegant stainless steel raw sewage automated “self-priming Siphon”. We still do not know why, so we just assuming they may be afraid of the “THE-www.copy-paste-community.com”… Therefore, we had to overcome our own engineering bottlenecks and “cracked our heads” to develop a “floating Valve” by our self, for pre-treated sewage only.

With BORDA e.V.’s financial support we were able to do so very well. In order to find out about all the “does & do-not’s” and bottlenecks, we tested and changed again and again under “dry” and “wet” conditions in a tank just simply by “try & error” in praxis. Finally we produced and delivered to Tanzania in January 2017, a simple “floating valve” unit as requested for a flow of Q = 65 l/s, made mainly out of very robust HDPE pipes and some parts of stainless steel, see photo and sketches on page 2 and 5.

Keeping in mind, “non-proprietary” technology "Open Source" by and for many", have in our belief much more sustainable benefits, compared to "proprietary & patent-driven technology by and for few". We just guessing, BORDA’s ongoing South-South technology transfer since many years is a good example in this regard.





Made mainly out of very robust HDPE pipes and some parts of stainless steel:




3-D drawing of automated “floating Valve”:




Find attached and probably later in SuSanA’s digital Bibliotheca 4 PDF-document, our:

- Text – Important & simple detailed engineering suggestions to do your DIY’s, our
- Technical paper with “rules of thumbs” how to do the basic engineering, our
- O&M manual and our
- Photo documentation on our “try & errors” in praxis.

All documents, texts and pictures are licensed to Creative Commons 4.0, see creativecommons.org/licenses/by-nc-sa/4.0/


1. DIY – automated “floating Valves” - for pre-treated sewage only:

Important & simple engineering suggestions (learned by doing) to do you’re DIY’s:

- Use only robust plastics e.g. PE and high grade stainless steel bolds and clamps for sewage, protect flexible pipe against solar radiation.
- Do not use bellows as flexible hoses (they are not long lasting and hindering flush out by it roughness).
- Clean minimum 1 x per year the floaters (inside pipe) with high pressure water.
- Never clean flexible hoses (joints) at all, to avoid damages.
- For your hydraulic flow calculation use simple pipe flow-equation, this is using 1 x “g”, starting conservative calculation from the bottom of distribution chamber only.
- Keep “velocity head” (speed) high as possible by avoiding frictions (like bellows, sharp bends and valves) within distribution pipe system towards CW-bed, most as possible. Designs this main pipe system like sewage gravity pipes, e.g. better 6 x 15 degrees bends them 1 x 90 degrees, slope minimum 1:100, minimum level difference (gravity) from distribution camber bottom to top of pipe at CW-bed min. ~0.5 m. If a very large “floating Valve” with a very high Q is in use, a smaller level difference say ~0.3 m is maybe possible too.

But if you do not like DIY, or “like to be a lazy engineer” or can not find a handy craftsman to create for you, your own DIY-“floating Valve” via Open Source, you may purchase from 5 different manufactures for “floating Valves”: Despite our draw back by company ALISTEP we still prefer their very well designed stainless steel raw sewage siphon’s, although some small changes we would recommend to improve more on their already high durability:

- in Austria: oepro.at/index.php/rohrventile.html

- in France:
- abt.fr/equipements/systeme-de-bachees/ou...c-mobile-pendulaire/
- www.alistep.com/?lang=en

- in USA & UK: www.rissyplastics.com/flout-systems/about-the-flout.html

- in Germany: www.aqua-verde.de



2. DIY – floating “self-priming Siphon’s” - for raw sewage:

Keeping in mind for all pipe-based and floating “self-priming siphon’s” the basic engineering by Dr.-Ing. Werner HEYN’s (“decrypted” in his German & US-Patent US1727828, Hamburg, Germany in 1929, is open since 1959) is a fixed “self-acting siphon”, original an idea for fixed river weirs only. In combination with this engineering idea, it is very easy to make by your self out of already in detail explained very simple Open Source DIY-“floating Valve”, a kind of floating and sinking-moving piped “weir”, a flexible very simple self-priming siphon” for raw sewage too, keeping Open Source and DIY approaches too. It is therefore very easy to enable an automated sucking out of an interval-tank and distributing raw sewage towards sludge separating gravel beds by gravity. You just have to turn the two bends 180 grad degree downwards and extend the same bends with some small length of pipes equally too. Make sure the outlet of siphon at distribution chamber is ~400-500 mm lower than the opposite suction head site of siphon.

Important & simple engineering suggestions (learned by doing) to do you’re DIY’s:

- Self-priming: Make sure “self-acting siphon” (a kind of floating valve, siphon and sinking piped “weir” in one device) is sinking by heavy weight always very fast to the bottom of interval-tank, to enable pushing & sucking down pipe blocking air out of bends by forcedly very fast water flow.
- Use only robust plastics e.g. thick wall HDPE pipes and high grade stainless steel bolds and clamps for sewage, protect flexible pipe against solar radiation.
- Use only smooch bending, avoid sharp corners and welds with beads inside pipe.
- Do not use bellows as flexible hoses (they are not long lasting and hindering flush out by it roughness).
- Clean minimum 1 x per year the floaters (inside pipe) with high pressure water.
- Never clean flexible hoses (joints) at all, to avoid damages.
- Keep “velocity head” (speed) high as possible by avoiding frictions (like bellows, sharp bends and valves) within distribution pipe system towards CW-bed, most as possible. Designs this main pipe system like sewage gravity pipes, e.g. better 6 x 15 degrees bends them 1 x 90 degrees, slope minimum 1:100, with a minimum level difference (gravity) from distribution camber bottom to top of pipe at CW-bed min. ~0.5 m. If a very large “floating Valve” with a very high Q is in use, a smaller level difference say ~0.3 m is maybe possible too.
- For your conservative hydraulic flow calculation use siphon-equation, this is using 2 x “g”, starting conservative calculation from the bottom of distribution chamber after the siphon .
Every siphon has a maximum drainage capacity at a given water level difference. It is calculated by (siphon-equation):
Q = Outflow coefficient x A x square root of (2 x g x h) in [m3/s]
with Outflow coefficient (normal Heyn-siphon, achieved values of = 0.5 - 0.6)
A = m2 Outflow cross section of the siphon (Pi/4 X d2)
H = m drop height of the siphon (delta h)
g = Acceleration due to gravity (g = 9.81 m/s2)

But if you do not like DIY, or “like to be a lazy engineer” and can not find a handy craftsman to create for you, your own DIY-“self-acting siphon” via Open Source, you may purchase from 4 French or 1 German supplier, your automated “self-priming siphon for raw sewage”. Despite our draw back by company ALISTEP, we still prefer their very well designed stainless steel raw sewage siphon’s. Although some small changes we would recommend to improve more on their already high durability.





DIY-example: “hydro-dynamic suction siphon” for raw sewage





5 manufactures for floating “self-acting siphon’s” for raw sewage:

- in France:

aquasaf.fr/en/
jean-voisin.fr/produits/equipements/chasse-poste/
www.alistep.com/?lang=en
www.ineautec.com

- in Germany: www.aqua-verde.de

Do you know any other "inventors" and manufactures on self-acting siphons for raw sewage around the globe? Kindly complete my list.


forum.susana.org/229-dewats-decentralise...ystem?start=12#21130
and
forum.susana.org/229-dewats-decentralise...ystem?start=12#18097

06 Apr 2017 16:22 #21130

siphon-update:
All "flexible self-acting siphon’s for raw sewage" are based on old ideas and patent of fixed self-acting siphon by Dr.–Ing. Werner HEYN from Hamburg, Germany: gif-Animation

Self-acting siphon - Patent US1727828 by Dr.-Ing. Werner HEYN from Hamburg, Germany, www.google.com/patents/US1727828 , ~1929, now open


Best Regards,
Detlef