Instructions for building UASBs?
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Instructions for building UASBs? 05 Jan 2013 12:17 #3042

  • canaday
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Hi everyone,

I have been reading about UASBs (Upflow Anaerobic Sludge Blankets), but have not found a detailed manual of how to design and build one.
Is there such a manual available on the internet?

I am especially interested in placing UASBs upstream of Vegetated Sand Filters, as a means of getting as much of the suspended solids out as possible and converting these solids into useable biogas. I am thinking about domestic wastewater and slaughterhouse wastewater. Even without the artificial wetland, a stand-alone UASB would be much, much better than the existing straight pipes to the rivers.

UASBs seem especially applicable here in the Amazon, where the soils are mostly all clay, so a 5-meter-deep reactor could be readily dug down into the ground and then the walls could get reinforced with ferrocement, bricks, concrete blocks, or something. This would also apply in much of the Andes, where there is a thick layer of compressed volcanic ash that also allows for deep digging. By being below ground, this should allow them to be gravity-fed.

All suggestions would be welcome.

Best wishes,
Chris Canaday
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com

Re: Instructions for building UASBs? 05 Jan 2013 22:39 #3044

  • AquaVerde
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Dear Chris,

Maybe you go for the very simple Anaerobic Baffled Reactor (ABR), which do not need deep digging. In simple terms an ABR is "only made" out of a settler and at least 4 UASBs in line. An ABR do not need any external power supply and pump if at least a small gravity of 20-30 cm is available.

The ABR was initially developed by Prof. McCarty and co-workers at Stanford University, USA (McCarty, 1981 scialert.net/fulltext/?doi=jas.2011.1449.1452&org=11).

www.sswm.info/category/implementation-to...tewater-treatments-8
www.akvo.org/wiki/index.php/Anaerobic_Baffled_Reactor

BORDAs Practical Guidebook (detailed manual) by Engineer SASSE: www.borda-net.org/fileadmin/borda-net/ne..._Guidebook_small.pdf
(with detailed equations)
Important Remark on the older manual:
!!! Based on practical experiences the Maximum up-flow velocity should 1 m/h not any more 2 m/h, inside the reactor cambers!!!

BORDA offers prefab ABRs made from fibreglass: www.aid-expo.com/Assets/UserData/aidex20...ons/WS14_AMiller.pdf
costs +/- 500 EUR/m3

On susana.org you can find drawings of an ABR made from concrete. But avoid just "Copy and Paste".

Even in cold European climate we made good experiences with our own small prefab ABRs made from PE, for domestic use (6 - 30 p.e.). Conservative COD reduction approx. 50% during winter and 70-80% during summer. Unfortunately our costly permission costs involved (approx. 14,000 EUR for permission per plant)in regard to German gas safety regulations, do not allow the customers to use the biogas out of small scale ABR-plants.

Good Luck

Detlef SCHWAGER
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Last Edit: 14 Jan 2013 09:25 by AquaVerde.

Re: Instructions for building UASBs? 08 Jan 2013 16:28 #3057

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Dear Chris,

I had recently the same problem, it seems that UASB is pretty spread in south america but not so much around europe.
From what I gathered at the time with old collegues, with UASB you're gaining a lot of volume (5h MRT against 1 day MRT for ABR) but you need to extract the sludge every week or so because the little hoses of the inlet pipe (bottom of the system) can get clogged quickly if sludge isn't pumped out regularly. On another hand, I'd be curious about the Gas production with MRT so short. If you find some interesting publications available, please share it I'd be very interested.

Good luck in yoru research,

ben

Re: Instructions for building UASBs? 14 Jan 2013 09:19 #3078

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Important Remark on the older manual:
!!! Based on practical experiences the Maximum up-flow velocity should only 1 m/h not any more 2 m/h, inside the reactor cambers!!!

BORDAs Practical Guidebook (detailed manual) by Engineer SASSE: www.borda-net.org/fileadmin/borda-net/ne..._Guidebook_small.pdf
(with detailed equations)
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Last Edit: 14 Jan 2013 09:24 by AquaVerde.

Re: Instructions for building UASBs? 15 Jan 2013 11:32 #3088

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Hi Chris,
when I started to design UASB I worked my way through the basic book by V Haandel and Lettinga
Anaerobic sewage treatment: a practical guide for regions with a hot climate. For me it was excellent as it discusses lots of design principals, of assumptions today there might me much more sophisticated books, but I like the in-depth approach. You have to see that the book is from 1994, so there are new developments but comparing what has been build here in Brazil (where we have lots of UASB) to what is described, you can see that the technology has not changed that much. Some of the following 4 aspects in the book are often underestimated and the description in the book makes it seem easier than it is:
• Problems with flow distribution
• Problems with scum build up
• Problems with sludge removal
• Problems with sealing the gas chamber to avoid venting
These aspects often led to failure.
I would recommend to be very, very careful and to have a look at a series of reactors while designing, they seem to be simple but they are tricky. Good pre-treatment is absolutely crucial.
But yes, UASBs are a very good, effective method of bringing down BOD for warm climates without the use of energy but generating energy, as well for domestic wastewater.

We are currently involved in the first project for larger biogas use from UASB in Brazil where we will generate 190 kW of electricity using the gas from the UASB (a plant with about 150 l/s). Later in the year we will report on that.

Regards
Christoph
Last Edit: 15 Jan 2013 12:32 by christoph.
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Re: Instructions for building UASBs? 16 Jan 2013 14:53 #3098

  • canaday
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Dear Christoph,

Thanks for this info and congratulations on your successes with UASBs in Brazil.

Is the Van Haandel and Lettinga book available somewhere on the internet?
Is there a time after which it would be legal to copy a book and post it on the internet (given this book is from 1994)?
Could this sort of book be posted on SuSanA.org?

How much scum and grease floats to the top? Does this flow continuously somewhere? Or does it get removed periodically?

What is the range of depths of your UASBs in Brazil? It seems that the deeper it is, the more water pressure and the more anaerobic. Or is this my imagination?

What pre-treatment do you do? I think of UASBs as pre-treatment before Vegetated Sand Filters.

Do your UASBs flow by gravity? Or are electric pumps used to have constant flows?

AguaVerde, thanks for the info on ABRs, but why do you consider these better than UASBs, aside from not having to dig so deep? In places like here in Amazon, the soil is often clayey and not hard to dig.

Best wishes,
Chris Canaday
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com

Re: Instructions for building UASBs? 16 Jan 2013 16:19 #3102

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Dear Chris,

Short answer, because of its simplicity in system and functionality ("low-tech") under harsh condition, as mentioned in text-books and based later on my own local experiences even in the cold climate too.

Good Luck

Detlef SCHWAGER
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Last Edit: 17 Jan 2013 17:58 by AquaVerde.

Re: Instructions for building UASBs? 17 Jan 2013 11:25 #3110

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Dear Chris,
some quick answers…as I learned today that long answers are in the danger of not beeing read .
• Maybe you did not see that I put the link for the book books.google.com.br/books?id=MB1SAAAAMAA...qi=2&redir_esc=y
(to the forum organizers – I find it difficult as well to see if there is a link or not)
• I have no idea about copy rights, but good parts are readable in google books.
“How much scum and grease floats to the top? Does this flow continuously somewhere? Or does it get removed periodically?“

Too much, especially in a slaughter house if you don´t have a very effective grease removal
Does this flow continuously somewhere? Or does it get removed periodically?

That is the problem. The flow to “somewhere” is not easy to solve, therefore most leave it on, resulting in very thick layers of scum which might as well block the gas. Manual cleaning is the most common but therefore you have to open the reactor and the gas goes off. We are working on solutions but there is no recipt.
What is the range of depths of your UASBs in Brazil?

UASB for domestic wastewater are in the range from 4,5 – 6 m of depth.
It seems that the deeper it is, the more water pressure and the more anaerobic. Or is this my imagination?

That is your imagination, the better process has nothing to do with the depth, it has to do with upflow velocity (to have the minimum “sludge blanket” (as from the name UASB Upflow Anaerobic Sludge Blanket)). It you have a very high velocitiy you get problems in the decantation, if you have a too low velocity you have a septic tank. Therefore large flux variations are a crucial point.
What pre-treatment do you do? I think of UASBs as pre-treatment before Vegetated Sand Filters.

Good screening is crucial to be able to distribute the wastewater by triangular weirs (if you are planning to do that), Sand removal is crucial as the sand fills up the reactor with the time and it forms a very hard mass together with the organic matter, which is not possible to be pumped out, Grease removal is crucial due to the reasons sited above. There fore I don´t use UASB for plants smaller than15.000 pe (just a rough number). My personal choice is: 5-50 pe. Septic tank, 50 – 2.000 p.e baffled reactor (ABR), 2.000 – 15.000 it depends, > 15.000 UASB.
Do your UASBs flow by gravity? Or are electric pumps used to have constant flows?

I did both already, no general idea.

I hope that helped. Just two more remarks. From a security in construction standpoint it does not sound too good to me to dig a hole with 5m depth and the idea of ferro cement for sure does not work. You need a VERY (sorry Jürgen I´m a fan of trolls and of capital letter use at for me it is a way to express what I think is important without doing anything else – just referring to another post at the forum here) good quality cement as there is strong H2SO4 corrosion.

Regards

Christoph
Last Edit: 17 Jan 2013 11:26 by christoph.

Re: Instructions for building UASBs? 17 Jan 2013 14:54 #3119

  • canaday
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Dear Christoph,

Thanks for this great info.

I did see the link you put in your long message, but I did not express 100% clearly that I am looking for a version I can READ on the internet and not just buy (which requires credit cards, time, etc.) I have not found any part of this book in Googlebooks, and your first link says "Kein E-Book verfügbar", the second link says "Nenhum e-book disponível", which I suspect both mean "no e-book available".

OK. So ferrocement is ruled out due to the H2SO4. What about a brick and cement mortar lining for the tank? What if we make a lining from PET plastic Coke bottles? (I have a couple of methods in mind for such a recycled PET lining.)

What do you make the hood for catching the gas out of? I was thinking of ferrocement, but that is ruled out. What about replacing the steel wires with non-corrodable plastic and adding latex into the cement?

Best wishes,
Chris Canaday
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com

Re: Instructions for building UASBs? Making liner from PET bottles? 23 Jan 2013 03:10 #3204

  • Taber
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Hi, Canaday--

You mentioned in this thread you have ideas regarding making (impervious?) wall liner out of PET plastic, as in Coke liter bottles. How might one seal such cut-out plastic to make an impervious liner? If practical this would be very useful for many other 'container' applications.
Regardez, Taber, Wetlands Work! Cambodia
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Re: Instructions for building UASBs? Making liner from PET bottles? 23 Jan 2013 04:11 #3206

  • canaday
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Hi Taber,

It is nice to hear from you. Are you still in Cambodia? How are your wetlands?

I presume PET plastic bottles would be much more impervious to the acids in a biogas reactor, such as the UASB, as compared to cement, steel or a mix of the two (ferrocement). I also presume that the liner would not have to be watertight, especially where the soils are water-saturated clay or where rivers, wells, etc. are over 16 meters away, plus suspended solids in the water should be expected to plug the spaces in the surrounding soil.

The two methods I have in mind are labor-intensive, although not terribly so. The first involves cutting the straight, cylindrical sections of 3-liter, which easily open out flat, like shingles. Holes can be perforated with hot metal and, then, the "shingles" can be woven together.

The second involves making columns of PET bottles of any size, which then get woven together with strips of the same PET plastic. The columns can then be filled with soil or cement.

I hope this is found to be useful.

Best wishes,
Chris Canaday
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com

Re: Instructions for building UASBs? Making liner from PET bottles? 23 Jan 2013 06:44 #3208

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Seems to me like that wouldn't give sufficient structural strength to avoid collapse, and since it is leaky it can not be used for a cover of a ferrocement structure.

Epoxy coats of cement structures are generally a good solution against H2S and other chemical corrosion in sewer pipes, so that is probably a suitable solution.

For lower tech / cheaper solutions... hmm maybe a tar coat would work if reapplied from time to time?
Otherwise...probably not suited for the huge size, but in-situ burned ceramics have also been used for bigger water storage containers, and might be an option.
Krischan Makowka
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Re: Instructions for building UASBs? Making liner from PET bottles? 23 Jan 2013 14:30 #3218

  • canaday
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Dear JKM,

Thanks for analyzing this.

I think the option of PET bottle columns filled with cement would be very stable against collapse, especially if steel rebar (or similar) is placed in the center of each column, which would serve for compacting the fresh cement and remain there for support. My concept is put horizontal strips of PET folded lengthwise (which has great tensile strength) or plastic rope (which would be easier and still presumably resistant to H2S) threaded through holes melted into the columns of PET bottles, to hold them together. These holes may need to be sealed with tar or something. So the cement and steel would be protected inside the PET.

The idea of burning in situ to convert clay walls into ceramic is very interesting in places where the water table is very low in the ground, for example in the Andes, where one can readily dig into the abundant compressed volcanic ash. The burning could be done progressively after each meter of digging. Are there any instructions for this available on the internet?

This is just brainstorming, so if I am wrong on any point, please do not hesitate to tell me.

Best wishes,
Chris Canaday
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com

Re: Instructions for building UASBs? Making liner from PET bottles? 23 Jan 2013 20:19 #3222

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Ahh, ok I misunderstood your idea, cement filled bottle columns might be strong enough. Horizontal connection would be probably the main design dificulty however.

Concerning the insitu fired clay... there isn't much and I just recently came across this idea. This document explains the process on page 31pp:
www.friendsofkitui.com/images/PDFs/TR28-...nwater%20STORAGE.pdf
However only for small (1.5m3) water tanks. Especially deeper holes would probably have to be artificially ventilated to have sufficient oxigen for the fire.
Krischan Makowka
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Re: Instructions for building UASBs? Making liner from PET bottles? 27 Jan 2013 10:47 #3268

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I would think that making shingles from PET bottles is a lot of work and if they are on the inside, they need to be fixed (held) in place in a very durable manner. It would be faster to line the inside of the reactor with butyl foil, ofcourse far more expensive, but smooth and very durable.
You can use the PET bottles as cavity wall, either having masonry on both sides or cast them centrally inside a concrete wall. This will reduce the amount of concrete and increases the wall stiffness. In addition it will improve the thermal insulation of the wall, making the reactor work at higher temperatures, which may be a benefit in colder climate zones/periods. For reinforcing the interior or exterior sides, glassfibre webbing (e.g. Vitrulan) would not be affected by the acids, but they have to be covered with cement mortar. When you build the installation it has to last 30 years, so economising on the building materials by using untested solutions is seldom a good idea. That is why I like to hear of any dyrale results with PET lining.
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Re: Instructions for building UASBs? 28 Jan 2013 11:22 #3273

  • MRonteltap
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Dear Chris and other authors:

You will likely not hear anything about building a reactor with PET bottles...., but we do have a course in anaerobic wastewater treatment coming up early March, with design and calculation of UASBs as an important aspect. It is a one week course, also the starting week of the 3 week module on Resource Oriented Wastewater Treatment and Sanitation. Teachers are prof. Jules van Lier, one of the successors (and former students) of Prof. Gatze Lettinga, and Prof. Carlos Chernicharo, who has a sea of expertise on UASBs in Brasil.

For this year the scholarship application is closed but for next year you can apply now.
Registration for this year is still open!

More information can be found on www.unesco-ihe.org/Education/Non-degree-...tment-and-Sanitation
and in the attached brochure. Oh for some reason the PDF does not attach.. I can send it via email upon request.

Please do not consider this hidden commercial; if it's interesting for you then it is; if not then not.

Best regards,
Mariska.
Last Edit: 28 Jan 2013 11:36 by MRonteltap.

Re: Instructions for building UASBs? 09 Feb 2013 16:51 #3433

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Dear Chris Canaday,

How fare are you with your possible UASBs?
Would be nice to here more from you on your subject in question mark.

Regards,

Detlef SCHWAGER
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Last Edit: 09 Feb 2013 16:52 by AquaVerde.

Re: Instructions for building UASBs? 04 Oct 2013 21:16 #5887

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Chris,
at ocw.tudelft.nl/courses/watermanagement/w...on-uasb-design-base/

you can find many good cc (open source)lecturing's via video and ppt about UASB's and AD-technology in general by Prof. Jules van Lier...

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Last Edit: 04 Oct 2013 23:37 by AquaVerde.
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Re: Instructions for building UASBs? 06 Oct 2013 05:21 #5893

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Dear Detlef,

Thank you very much for this great link (with other chapters that also look very interesting). If online books become available, with more details on building UASBs, this would also be very appreciated.

I still have yet to build my first UASB, but I think I am starting to digest the idea.

Best wishes,
Chris Canaday
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com

Re: Instructions for building UASBs? 06 Oct 2013 10:54 #5895

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just a suggestion:
get on possible cc (open source) online books & handy manuals in direct contact to Prof. Jules van Lier, NL at TU Delft, I guess he will be very helpful to you on less sophisticated and more robust designs for smaller decentralized applications, like he explained in Columbia and Basil. On latest high tech UASB developments I guess not.

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additional see online page 427 of Chapter 16 of his book about his view on ABRs (...a series of serially operated UASB units.) In my opinion ABR's are only a purposely simplified version of UASB design. The potential of this purposely staged design is not used up to now and not further developed. I am wondering why, as the mentioned problem of flushing out of granular (sludge) is not really a big problem, if geometric design is based on a low up stream velocity (e.g. 0,1 - 0,6 m/h) and so on. Even the SRT's in each camber can be nicely controlled by separated sludge outlets for each camber.

Maybe I am missing out some more important technical issues, as I am probably like you, just learning by doing...

Under our cold climate it will be already a big financial success, if not only during summer time, even during winter large amount of sludge been reduced (theoretical up to 90% via AD!) by a purposely simplified AD-System, even if only small amounts of bio-gas volumes been generated and used. This "sludgy" approach would be mainly for large centralized wwtp's from economical and environmental advantages. So I am not only targeting decentralized systems with purposely simplified UASB. E.g. see UK/US-ABR ATKINS study.
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Last Edit: 06 Oct 2013 11:31 by AquaVerde.

Re: Instructions for building UASBs? 17 Oct 2013 19:04 #6031

  • F H Mughal
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While there are few plus points of UASB, like: production of low sludge, higher degree of waste stabilization, no oxygen requirements, production of methane gas and, low nutrient requirements (USABs are particularly effective in tropical locations where temperatures are warmer and relatively stable), the process has some de-merits to its credit.

A major risk with a UASB is the possibility of washout of the biomass if the HRT (hydraulic retention time) is too low. To maintain the population of useful microorganisms and anaerobes a larger reactor volume or HRT may be required which can lead to higher capital costs.

The UASB has a long start up time. Recovery from stressed conditions can also take many days, making control of the reactor important. Control of factors that will affect operation include temperature, pH and influx of any toxic substances in the feed stream. Toxics in raw wastewaters are common in Pakistan.

Operation of the UASB requires trained and experienced operators. USAB has been used, typically, for industrial wastewater treatment and seen as less effective on dilute municipal feeds but more recent design improvements have seen the use of UASB in municipal sewage treatment in countries such as Brazil.

Anaerobic systems for waste treatment have been used since late 19th century, but their use has been limited due to restricted treatment efficiencies. A closer look at the theoretical considerations (see below) will further reflect on their restrictions. Relative to anaerobic systems, aerobic systems, such as activated sludge process, trickling filters, oxidation ponds and aerated lagoons, are more common.

Back in 1968, P L McCarty and Young did a lot of work on anaerobic digestion. USABs were developed by Lettinga and his co-workers in Holland in the early 1970's.

Theoretical Considerations

Anaerobic digestion is a three-stage process. In the first stage, the complex insoluble organics are hydrolyzed to simple soluble organics by the extra cellular enzymes. During this stage, the cellulose and starch are hydrolyzed to simple sugars, while proteins bifurcate into amino acids. In the second stage, called the acid phase, the acid formers (various species of Pseudomonos, Alcaligens, Flavobacterium, Escherichia and Aerobacter) convert simple organics to organic fatty acids (acetic acid). This results in higher acid concentration and low pH. In the third stage, called methane phase, methane formers utilize the organic acids and metabolized them to methane and carbon dioxide. Amino acids give rise to ammonia, which in turn, neutralize the remaining acids.

Methane formers (species of Methanobacterium, Methanococcus and Methanosarcina) are highly frail in nature. They are strict anaerobes, grow over a wide range of temperature, difficult to cultivate and, they remain inalienable. They are highly sensitive to low pH conditions.

These concomitant reactions in actual digestion occur simultaneously. Flawless performance of the digester will take place only when there is a balanced bacterial population of acid formers and methane formers, or, in other words, the volatile acids production equals volatile acids breakdown. If the volatile acids formation is greater than its breakdown (which usually is the case, in actual digesters), the pH lowers, inhibition or wash-out of methane formers occurs and, the process fails, biologically.

F H Mughal
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Karachi, Pakistan

Re: Instructions for building UASBs? 18 Oct 2013 08:20 #6038

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Dear Mughal,
A major risk with a UASB is the possibility of washout of the biomass if the HRT is too low.

I guess you have a typing error and probably "if is too high" in mind?

All the Theoretical Considerations are known. Do you have practical considerations on the the UASB and ABR subject?
All the best
Detlef
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Last Edit: 18 Oct 2013 08:25 by AquaVerde.

Re: Instructions for building UASBs? 20 Oct 2013 05:56 #6048

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Dear Detlef,

At lower hydraulic retention times (time for the contents to remain in the reactor), there is significant possibilities of washout of the biomass. That means, it would be difficult to maintain desired number of bacterial population in the system. To maintain adequate population on anaerobes, higher HRTs are required, or, larger reactor volumes.

What I have stated before the theoretical considerations, are the practical condiderations.

F H Mughal
F H Mughal (Mr.)
Karachi, Pakistan

Re: Instructions for building UASBs? 20 Oct 2013 07:47 #6051

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Dear Mughal,

Thanks for your clarification. It is my , English is not my first language, so I got mixed up.

In plain English, in my practical consideration just for planing of simple COD-ABRs avoiding washouts of biomass, I use a low up-flow velocity [Vup] at peaks not more them 0,6 m/h (better less) and a long HRT not less them 2 better 3 days. For Biogas-ABRs it needs more know-how and empiric science...

May you come in with your experiences on that topic?

In general, the necessary reactor volume for anaerobic wwtp technologies you can not avoid, it only seams large, but is still smaller in comparison to aerobic wwtp technologies for reactor and sludge treatment plus its high energy demands. Special in warm areas the anaerobic wwtp technologies have many advantages.
All is based on empiric science by others.

All the best
Detlef
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Last Edit: 20 Oct 2013 07:48 by AquaVerde.

Re: Instructions for building UASBs? 20 Oct 2013 12:40 #6052

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Dear Mughal,
do you do research on UASB?
I would like to know a bit more about how you calculate the retention time.
(correction after an observation from Mughal)
On what time do you calculate the HRT?
a) Volume reactor (m³) / Wastewater flow (m³/h) = HRT (h)
or
b) "Sludge reaction volume" (m³) / Wastewater flow (m³/h) = Reaction HRT (h)
or
c) "effective sludge reaction volume"* (m³)/ Wastewater flow (m³/h) = effective reaction HRT (h)
*(which would be just considering the volume until reaching the decantation area)

In my view b or c are the more correct numbers when talking about HRT for UASB.

In separate there should be an analysis of the decantation time which is in my opinion the responsible factor for losing sludge, not the overall HRT.

What do you think?

Yours

Christoph
Last Edit: 26 Oct 2013 13:29 by christoph.

Re: Instructions for building UASBs? 23 Oct 2013 16:59 #6106

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Dear Detlef,

In the first case, I would suggest HRT of 3 days (as you rightly point out). HRT goes hand-in-hand with SRT (solids retention time), meaning that appropriate SRT has to be maintained in the system. The treatment efficiency of the system is directly related to the SRT.

SRT is the ratio of suspended solids (SS) in the system to the SS removed per day from the system.

SRT is also defined as the reciprocal of specific growth rate, which is the total weight of SS in the system, divided by the total weight of SS leaving the system per day, including those that are purposely wasted or lost in the effluent.

Suffice to say that for achieving a high degree of treatment efficiency, the microorganisms should be given sufficient time in the system, so as to grow, coalesce and degrade the substrate before they are exterminated. This elucidate pertinently why at the lower temperatures, the SRT should be increased correspondingly to compensate for the lowering of the temperature, as the agility of the microorganisms gets retarded at such relegated temperatures.

For biogas, I’m attaching some publications, which should help you in your work.

Sectt: Please check for copyright issues, before uploading.

All the best,

F H Mughal


Dear Christoph,

No, I’m afraid, I do not do research on UASBs.

I’m sorry, but I could not comprehend your calculations of HRT. If you divide volume by volume, how can you get time – the hydraulic retention time?

HRT is calculated as the volume of the reactor divided by the wastewater flow rate.

Could I kindly request that you consult the following authoritative publications, as they will give you a whole lot of technical information:

1. Wastewater Engineering, by Metcalf & Eddy
2. Water and Wastewater Treatment, by Fair, Geyer and Okun, Vols I and II
3. Wastewater Treatment Plant Design, by the then US Water Pollution Control Federation, now Water Environment Federation

Smiles,

F H Mughal
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Re: Instructions for building UASBs? 23 Oct 2013 18:52 #6109

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Dear Mughal,

Thanks that was very helpful. Especially the PDF with bio-gas experiences from other cold countries. Again just COD reductions is easy to do with a large ABR, even in the cold. Getting out enough bio-gas is a very different story in the cold.

I calculated for domestic sewage of a AD wwtp a bio-gas energy value approx.. 100 - 150 kWh/p.e./a, conservative 100 = 0,27 kWh/p.e./d, suggesting a very well thermal insulates ABR with a heat-pump to "re-use" heat after reactor for heating up inflow. For me the ABR's are "only" improved/simplified UASB-versions.

Let me make a prognosis on this and let me have a very big mouth too :
"The combination between co-substrate, thermal insulation, heat-pump and improved/simplified UASB (and bio-gas used in Stirling-CHP) will be the future "KEY-Technology" and first step of future wwtp's in cold areas for domestic sewage. Being a future bag-boon of permanent renewable energy production in times of no sun and wind. The simplicity of Activated Sludge Technology with its very high energy demand, is not the future."

see developments in NL: energiefabriek.com/english




Best Regards,
Detlef

No. 15 und 16:
ocw.tudelft.nl/courses/watermanagement/w...ctures/15-wwtp-2030/
ocw.tudelft.nl/courses/watermanagement/w...he-resource-factory/
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Last Edit: 24 Oct 2013 16:29 by AquaVerde.

Re: Instructions for building UASBs? 25 Oct 2013 10:03 #6139

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Hallo Chris,

Maybe you know this already: Lettinga Associates Foundation (LeAF)
www.leaf-wageningen.nl/en/leaf/For-whom/Public-sector-NGOs.htm

Regards,
Detlef
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Re: Instructions for building UASBs? 26 Oct 2013 13:20 #6154

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Dear Mughal,

sorry for beeing so wrong in expression.I must have been drunk . Thanks for the correction, I corrected the post mentioning your intervention.. thought it is better to correct the post as it is not good to have really wrong observations/comments.
Hope my question gets clear now, if not I can do a drawing..

Thanks for the very basic book hints, with that posting I deserved it .

Cheers
Christoph
Last Edit: 26 Oct 2013 13:30 by christoph.
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Re: Instructions for building UASBs? 03 Nov 2013 08:39 #6253

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Dear colleagues,

With the permission of Mr. Heinz-Peter MANG, please find attached 2 papers from "2013 Beijing International Environmental Technology Symposium", 20-23 October 2013, University of Science and Technology Beijing, China and one paper from 2012:

- Greenhouse Gas Emission (GHG) made by wwtp's in China, 2013
- Summary on Research and application of anaerobic baffled reactor (ABR) in China, 2013
- Summary on DEWATS (ABR) in rural and cold areas in China, 2012

Very interesting as it is about extended daily use of DEWATS technologies even under the cold condition of North-China and outside from University laboratory settings.

2 Questions to the SUSANA-secretariat:
1. Do you store made annexes in an electronic library for all users to find again easily?

As fare I understand within the susana-search by keywords you can not find content of attachments of older contributions if they do not have the keyword in their file name. Only by luck you can find made contributions (attachments) by searching trough old messages/contributions.
2. Could it be possible to extent the susana-search to text of made attachments?

Regards,
Detlef SCHWAGER
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Re: Instructions for building UASBs? 20 May 2014 08:42 #8668

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Dear UASB experts,
Greetings from Dhaka! I have skimmed through this tread and found some interesting information but not exactly what I need right now for UASB. ! I am in Dhaka and urgently need a ballpark number of space requirements for a UASB process for fecal sludge. I do not need to design at this point, just an idea in terms of space to compare to other fecal sludge treatment technologies (e.g. the LaDePa, drying beds and co-composting, for which I have an idea space-wise already). Space is of uttermost importance in Dhaka, so it is of a real concern in the decision-making process for choice of options to look closer at. We're talking immense volumes of fecal sludge and septic tank sludge produced here. The one catchment area I am looking at right now is projected to have 1 million people on on-site after implementation of the Master Plan (65% sewering). With an average daily production of FS of 1.5 L/c/day, it means that each day 1500 m3 of fecal sludge is produced and needs to be handled... I'd be most grateful for any help I could get on ballpark space requirement numbers, e.g. m2/m3 FS or any other way that I can translate into the situation here in Dhaka, for UASB for FS treatment! Many thanks in advance!!

Kind regards

Elisabeth Kvarnström

Re: Instructions for building UASBs? 20 May 2014 08:58 #8669

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Hallo Elisabeth,

I am not an "EXPERT"
Please contact Jules van Lier - CITG, NL: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
direct.

Good luck.
Detlef
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Last Edit: 20 May 2014 09:11 by AquaVerde.

Re: Instructions for building UASBs? 20 May 2014 09:37 #8672

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Thank you, Detlef! Will do! And, yes, you are def. more expert than I am! .

Kind regards

Elisabeth

Re: Instructions for building UASBs & ABRs? 03 Jun 2014 13:22 #8843

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Dear Colleagues at Susana-office,

With the direct permission of Prof. Perry McCarty may you add this US-patent (PDF) to the public library of susana.org. The ABR-patents are so old that time has run out to enforce them. I don't believe anyone can now have a legitimate claim on a patent on the basic aspects of the ABR anymore, although they could have on some finer details, which others can probably get around if they wish. All is now just "Stand der Technik" = 'state of the art'.

It is my intention all the basic aspects/details of an ABR (bioconversion reactor) are more in public and coming from the original source!


McCarty, P. L. and Bachmann, A., "Bioconversion Reactor," U.S. Patent No. 5,091,315 (February 25, 1992).
McCarty, P. L. and Bachmann, A., "Bioconversion Reactor," European Patent No. 0213691 (July 22, 1992).

www.google.com/patents/US5091315



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This invention was made with Government support under Contract No. EG-77-C-01-4042 awarded by the Department of Energy to the solar Energy Research Institute (SERI). The invention was developed at Stanford University under Subcontract No. XR-9-8174-1 awarded to the Board of Trustees at Leland Stanford, Jr. University by SERI. The Government has certain rights in this invention.


I found this text part very interesting, as it showing that in USA important results of R&D which been funded by tax-payers money ending not up only for personal gain by the inventors. As fare I know in Germany is "privatizing" of public funded R&D-work just the standard. Maybe someone can correct me on this?

Detlef
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Last Edit: 03 Jun 2014 13:28 by AquaVerde.
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