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CO2 capture and p[roduction for AD. Where electronics come in

large_ghostman

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The following is taken mainly from a closed group site, the reason for posting is the recent Bio Methane conference i went to in Birmingham. But also because i started a post on mesh networks, i couldnt think of a good example to use for mesh networks. After the conference it occurred to me that one of the newest plants being designed for AD is going to use a true mesh network.

For those that dont know, i have alot to do with AD and biomethane. Soap is my day job but AD is my first love and research area, it combines electronics and science all in one, but for now wouldnt pay the bills!!

So i figured I would take part of the talk i gave at the conference and add in my idea for a mesh network. Then i have a solid base to finish the mesh network post using a real example. Modern electronics has made a big difference to environmental science, i got into it because of my love for electronics. Actually its pretty rare to find people on both sides of the fence, i honestly thought it would be more common.

This should also explain the obscure post i am doing on Microbial Cells, the point of them is not just tiny amounts of electric generation, but as you will see they serve a couple of other functions, one being worth a huge amount of cash from a really odd source. I wont post anything to do with information held under NDA, this year on nation biomethane day everyone at the conference after meeting signed one, it wasnt until i got home i realized why.

One of the better talks was by a numpty who read out an entire project that hasnt been published yet!! whats worse is he gave away his companies entire process for one of the best systems on the market, none of it was on purpose but AD companies are not good at sharing information or bio samples :D.

Another 20 mins and i can start to grab the papers off my hard drive, i will start with a quick overview then get down into it. My own septic tank system uses alot of the technology but is mainly hard wired, i have used mainly silicon labs boards and Linear tech stuff (as they were then), this is because they kindly sponsored me free of charge with free dev kits.

They also have some of the very best micro dev kits etc around. But any code posted should work on any ARM chip, i have used M0 M3 M4 cortex cores mainly with a good splosh of pic 18f and a couple of arduinos, all topped with a raspberry :D
 

large_ghostman

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I will start to post pics later of all the equipment thats going to be used, anyone with a skill set we could use is welcome to chip in, i will post up everything I can, there is also a dedicated website and forum for the project. So far we are working with a good number of people on this, but lack electronics and electrical people, also those with engine skills as we want to alter a 2.4kW petrol generator to be dual fuel. We do have a UK based old skool machinist who is going to make some parts for us, but he is 89 and obviously while highly skilled, it takes him a couple of hours to walk to the lathe let alone use it :D, dont worry he is aware i tell people this :p
 

JimB

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but he is 89 and obviously while highly skilled, it takes him a couple of hours to walk to the lathe let alone use it :D, dont worry he is aware i tell people this :p
Yes, and you should hear some of the things that he says about you! :eek:

JimB
 

large_ghostman

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Most Helpful Member
Yes, and you should hear some of the things that he says about you! :eek:

JimB
Apparently its mild compared to what you say about me lol :p
 

camerart

Active Member
Hi L,
I've been playing with engines for years, but basically had no interest from anyone, so here's my design for a flywheel less engine as a generator It's only in ideas form, but your engine expert may be able to assess it's worth.
Use it as you wish.
Camerart
 

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large_ghostman

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THX engines are his domain not mine :D.

I pass everything on like that to him. I had hoped to start the electronics side, but we havnt set the reactors up as we had a bank holiday and i am waiting for a new rubber seal, should be here in the morning with luck. Because we flush with hydrogen, we use new top seals every time, a small work area for this set up means i got to be careful with leaks etc
 

Pommie

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Most Helpful Member
I'm guessing that the abbreviation AD is used without explanation on other forums that you frequent. I have no idea what it stands for.

Mike.
 

large_ghostman

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Most Helpful Member
I'm guessing that the abbreviation AD is used without explanation on other forums that you frequent. I have no idea what it stands for.

Mike.
Yes sorry Mike, Mick is correct. I have mentioned the long version a couple of times, but to be fair its only this kind of forum you would use AD. Its lazy and i would get picked up for ir on Digestion sites because it dosnt distinguish between Aerobic and anaerobic , both systems are in use. So from now on i will simply use Bio Digester.

Actually its a lazy conference thing i got in the habit a couple of weeks ago making slides for power point.
 

large_ghostman

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Most Helpful Member
There is another site we are building, its purely experimental to look at some systems that have been discovered. Last year alot of money was dumped into a research area and recently alot of it got published (mostly closed publishing for 6 months).

Its made others go off in all kinds of directions, many think Bio methane industry is full of large companies researching, truth is most the new stuff has been done by small teams, many have grouped in loose alliances, the universities mainly just want to study and publish, the smaller companies are mainly consultants. Then you have manufacturers who on the whole build what they are asked for, so in alot of ways its a new fronteir with a big shift away from single batch type systems, especially as its been discovered where the real value is in the technology.

NASA has also started looking into it for Mars type missions because of aspects of the chemistry loan themselves to solving some problems they faced in space.
 

large_ghostman

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Most Helpful Member
Its one of the few truly closed loop systems, or rather the potential for being a closed loop system
 

Mickster

Well-Known Member
IMO, if the first AD-related post in a thread has something like "my latest project involves AD (Anaerobic Digestion) and this involves X,Y,Z...." then that is sufficient to inform viewers with regard to the topic of concern. "AD" is acceptable from then on.
Again, IMO, there's no need to use alternative descriptors, once the correct one is outlined.
 

large_ghostman

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Most Helpful Member
IMO, if the first AD-related post in a thread has something like "my latest project involves AD (Anaerobic Digestion) and this involves X,Y,Z...." then that is sufficient to inform viewers with regard to the topic of concern. "AD" is acceptable from then on.
Again, IMO, there's no need to use alternative descriptors, once the correct one is outlined.
I thought i had spouted so much about it i had made it clear, but AD as a description is frowned upon because it could mean either.

True microbial cells for example have two sides, one with oxygen and the other without
 

large_ghostman

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Most Helpful Member
BUT Microbial cells turn out to have a little magic about them :D.
 

Mickster

Well-Known Member
Sure, but if you declare your intended target - Aerobic vs Anaerobic - the onus is on the viewer to make sure they read all of the thread and respond to the correct terms.
 

camerart

Active Member
Hi,
I had to look up AD, and now realise that it can be read ambiguously.
As an encouragement to anyone who drifts onto a thread, I would tend to make it easier for them, by using the long version instead.
C
 
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large_ghostman

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Hi,
I had to look up AD, and now realise that it can be read ambiguously.
As an encouragement to anyone who drifts onto a thread, I would tend to make it easier for them, by using the long version instead.
C
I agree as above, AD is also often incorrect. Its funny but on sites dedicated to those working in this area i go mad about acronyms!! Then i did the talk a week or so ago at a conference, because of limited space on power point slides i used alot of acronyms. I was aware the audience on the whole would know them on the whole, BUT even a recent blog post i did i have started using them!:mad:.

Its a pet peeve and a really bad habit, very lame excuse but this keyboard keeps skipping letters......yes i said it was a lame excuse.

On a brighter note, we have been granted a license to use a modified bacteria for Digestion, well technically its a microbe not a Bacterium. One of the first 'designer' microbes for digesters, they are extremely difficult to isolate and purify, then getting altered into them is another hurdle. Its taken alot of work over nearly 3 years to get this far with it, I should get the certificate this week. Obviously I will share a pic of it! The real breakthrough with it is we can encapsulate it into alginate beads.

Next job is to scale up and try and produce enough of the microbe to sell them as pre activated bead beds. Sounds easy but we have had to modify 2 microbiology CO2 incubators into Anaerobic incubators, its not been cheap to get this far. Also we didnt have the electroporation machine, so all the plasmids etc have been inserted using heat shock treatment and markers. The worse part is making a glove box thats air tight and contains Hydrogen and Butane.

But each day is a step closer to production and full time employment doing this stuff, like most companies we will get the reactors built by plastics companies to our design, its a shame that alot of the manufacturing has to be outsourced to China.

If anyone is interested, we are going to decom an older system we put in a test site. Its to get ready for a newer version, if people want to see what a full sized multi chamber system with pre and post treatment chambers looks like, i will take pics when we take it out. We didnt make the reactors, although we did design them. Same with the control systems etc. Its only 12 months old, but they want a bigger unit and the newer type system we are working on, its going to a local company.
 

Western

Member
I am interested in some photos thanks ... and also some more idea of what level/scale these devices operate at ... experimental or fully fledged etc.

I was also very interested in the other thread where you were talking about your garden shed and its dirty little secrets ... but that thread got a little derailed, so I’ll flag my interest here.

It’s not much help to you coz we’re down in Aust ... but we do have plenty of clay on our property ... and your comment ... “ If you have an acre of land set to grass, and two - three sheep on it, a house of 3-4 people and access to organic material ... “ also got my attention.
 

large_ghostman

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Most Helpful Member
I am interested in some photos thanks ... and also some more idea of what level/scale these devices operate at ... experimental or fully fledged etc.

I was also very interested in the other thread where you were talking about your garden shed and its dirty little secrets ... but that thread got a little derailed, so I’ll flag my interest here.

It’s not much help to you coz we’re down in Aust ... but we do have plenty of clay on our property ... and your comment ... “ If you have an acre of land set to grass, and two - three sheep on it, a house of 3-4 people and access to organic material ... “ also got my attention.
Hi
I will give you some detail here. We do have a couple of company blogs where more detail is given, but most the detailed stuff is hidden in a customer section and our research site which is password protected. We will be opening some of that up to a wider audience, but didnt want it completely public as the time taken to deal with spam etc is a nightmare.

Scale wise we operate like most companies who do both research and consultancy, we also implement systems but like most we dont manufacture the actual reactors as the cost of a plant to mold plastic etc is a non starter. Scale wise all new systems in most companies start at lab scale, volume wise depends on the system. Single reactor batch systems are normally around 1-3 ltr, the reason is both cost and safety. Generally if you can get a system working with lab glass on a small scale, then it will almost always scale up better.

So lab scale gives the best of all worlds, from a safety aspect if your working on a new system or if you mainly focus on the newer multi chamber continuous flow systems like we do, then safety is a big issue as your dealing with explosive and inflammable gases, its also harder to montor mid and full scale systems when your trying new things. Again if it works on lab scale then its more likely to work when scaled up.

The latest system we are working on is roughly going to be 5-12 ltrs lab scale, this is as large as we have gone so far and is about as large as normal reactor lab with several systems in. From Lab scale we build proof of concept system to get a good idea of full scale production parameters, for us this turned out to be our septic tank with several other chambers added. Normally you would aim for around 150 ltr upto 600 ltr, because we had the land and a Victorian brick septic tank, we got hold of some 'onion' type plastic septic tanks and added those.

The control part and pump house is an outbuilding, the tanks are 600 yards from the house so a safe distance. Total capacity of this system is nearly 4000 ltrs which is a small scale full sized type capacity, we used it as proof of concept and it got us our first 'job' in digestion.

The other part you mention is the ground battery system, this is with clay for best results as acidic peat dosnt seem to work well, most of it is no big secret and is based on Edison cell type technology. The clay is more of a electrolyte than anything, or so we thought...... If you want i will add you to a list of a people with access to the day to day data and information on it, its still very experimental and we dont really understand how it works yet. Your welcome to view the less private side of the experiment site, obviously some the info we dont give out in case we end up in position to patent it.

If you use a modern continuous flow multi chamber system for digestion, and add in decent insulation around the house etc, then home systems work and work well. An example being something like 3-4 1,200ltr onions or even IBC type containers (International Bulk Containers) the ones in a steel cage are cheap, you can build a system that would give you around 14 hours of cooking gas a day, but if you can feed it enough material (hence the sheep,grass and wood waste) then a family of four can get alot of energy from it.

Keep in ind this is a quick run down, you need to use it as part of a closed system, so things like evacuated solar heating panels and a storage system for both gas and electric (hence the ground battery). The biggest problem we were facing is sludge and how best to break down carbon sources like wood etc, recently both of these seem to have been solved, or more accurately those are the things we are working on right now.

In a batch system you empty after each batch and the sludge goes onto the field or whatever, this is wasteful so we designed a continuous system, the liquid digest-ate was fed into a large hydroponic system, if you take the CO2 from generator exhaust or the digester and inject ito the waste stream it feeds the plant roots. To get an idea how how successful that is, look up dutch planted aquarium systems.
The following is an example
dutch.jpg
What most have in common to get plant growth like that is CO2 injection systems, the CO2 is dissolved into water to form Carbonic Acid. Carbonic Acid is a rich Carbon source that has extremely high bioavailability to plants. If you use it on certain hydroponic systems it works with the roots of terrestrial plants just as well as the aquarium above. What most people dont understand is many of these aquariums like above, contain plants that in the wild are only totally submerged during the rainy season etc.

Very few aquatic plants actually live fully submerged all year, although the above pick has a 50/50 mix by the look of it lol. Anyway once you understand that you realize that feeding Carbon to the root system has alot of advantages over feeding it to the leaves via the air. If you air feed CO2 then you have to be exact in temperature and humidity, the plants dosnt feed constantly via the leaves, the stomata on the leaf closes alot to conserve water etc, this is widely affected by temp and humidity.

However the roots can feed mot of the time so the uptake of carbon is much greater. The downside is if you feed high amounts of carbon then you have to make sure the plant is supplied with enough other nutrients to use it. This is where the digestate comes in, the plants strip out the nitrates and the other macro/micro nutrients at a very fast rate. If you cycle the water from the last stage enough times around the hydro system, you get water that is depleted in nitrate and minerals. Where i live this is highly valued as we live in a nitrate sensitive area.

So SEPA which is our Scottish Environmental Protection Agency, are keen on these systems as the discharged from the digester ends up as depleted water which is simply released like normal. Normally to get the most from these systems, you use a high value crop/crops so things like tomatoes or strawberries, some grow exotics like Orchids etc. You use any waste heat from the electric generators or pre treatment systems to heat the poly tunnels or green houses.

The idea is to waste nothing as far as you can, this maximizes the return on the system, The problem we had with the first continuous feed system was a very slow build up of sludge, this is spent organic material and dosnt produce methane anymore, it can be microbialy broken down into CO2 eventually. But then you can start to poison the system with too much CO2 in the digester, the breakthrough was microbial cells, this sludge in the new system is passed to a final chamber, where with some magic and microbes it is rapidly broken down into CO2 and also produces electricity at the same time, its not huge amounts of electric, but enough to run the microbe cell and a little extra.

The real benefit comes from desludging and producing CO2 which can be recycled into the system or we are looking at a system where it would mixed with Hydrogen from electrolysis from wind turbines, passed over a catalyst and produce Methane, this is the NASA mars research area (roughly), we are looking at some slightly different and for us the real payday with this system is a by product, if we can get it to run properly then the microbe end cell would make more money than the entire system on a daily basis, but its early days at the moment with side of it.

Currently we have recently been invited to put forward plans for some digesters in southern Scotland, Cumbria and Northumberland, our local authority has teamed up with another one. On top of that they are forming a group with the local water company and wanting to trial a digester at a water treatment plant, this is where our bio diesel from Fat bergs comes in. Most of this has happened in the last few months, it took a while to get a continuous system built, banks wouldnt lend and we had to self fund.

Then we had a few people come and look at our home system and got an offer to build our first full scale plant, its fairly small but it gave us the 'IN' with the local authority etc and proved our system worked and was alot more efficient than standard. I cant take all the credit by a long way, i have a business partner who has helped massively to get this off the ground, i have had access to some university resource for sharing information etc and now that i am doing a semi part time masters in Environmental engineering that has also helped alot.

So maybe 3-4 years of work and god alone knows how many years i messed in my dads lab!! Is just starting to pay off, it isnt something i have mentioned that much on here until recently, most regulars where aware i 'dabbled' with bio fuels but few actually knew just how far into it i was. It was kinda fringe a few years back so most people into it kept quiet, alot like being a matchbox collector :D. You do it and love it but dont really tell people about your hobby lol.

I hope that helps you a bit, i will pm you a log in when the new experiment blog and site is ready. It will give you more info than i can put here, although the new control system stuff will be posted here as its more relevant with electronics.
 

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