loading

The algae experiment: How to build your own algae photo-bioreactor.

Featured
Picture of the algae experiment: How to build your own algae photo-bioreactor.

In this instructable we will go over how to construct an at-home version of a photo-bioreactor which will use solar energy and artificial lighting with carbon dioxide to produce algae biomass.

The aim of this project is to create an model which harbors an ecosystem fit to help us escape a fossil fuel economy. We are in an era that is experiencing a shift from humanity trying to dominate nature, to then trying to preserve parts of nature and now trying to reach a reconciliation with nature. This is the algae experiment; an idea that is trying to move away from a linear wasteful and polluting way of using resources to a closed loop system where all resources are kept in a closed loop cycle.

Check it out working.

https://www.youtube.com/playlist?list=PL315E7074BE...

Follow the possibilities of harvesting algae for fuel & see the difficulties met along this journey on-line at

@@@: thealgaeexperiment.tumblr.com

a published paper on the subject can be found on

@@@: http://issuu.com/mouchmouch/docs/thealgaeexperime...

For more info or to get in touch you can reach me at

http://www.mouchmouch.com

 
Remove these adsRemove these ads by Signing Up

Step 1: Shape, size & materiality

Picture of Shape, size & materiality
IMG_1577 - Copy.JPG
020-1.png
020.jpg
The over all shape of the photo bioreactor is inspired from a previous project I had been working on where it follows a mean summer solar path of the UK. It is meant to be both an educational model but also embody certain architectural elements within allowing it to possibly be viewed as an informational pavilion.

Step 2: The ribs

Picture of The ribs
IMG_5799.JPG
IMG_5803.JPG
IMG_5972.JPG
IMG_5802.JPG
IMG_2322.JPG
I considered using two materials for the support system.

I tried clear acrylic so as not detract from the function, which would be the algae tubes containing the algae. However. having to deal with all the transparencies of the materials made the model seem very confusing.

I needed each rib to consist of two pieces of wood in order to provide a stable ‘leg’ for each segment whilst I would be putting the model together but also to be able to withstand any rocking from pressure the model would experience during the cultivation hours. I ordered 50 M4 grub screws with a cup point and 150 M4 hexagon nuts and got started on the ribs. (M4 denotes the diameter of the screw; 4mm) I spaced the ribs apart 20mm which allowed them to be able to free stand. Together all 5 sets made a very sturdy model base.

Step 3: The Tubes

Picture of The Tubes
IMG_5807.JPG
IMG_5827.JPG
IMG_2268.JPG
I wanted to use a closed loop system where the algae would travel constantly and safely without getting contaminated, so using clear acrylic tubes was the best option.

I initially wanted to use 15mm outer diameter tubes with an inner diameter of 12mm in order to carry the water required to grow the algae, as well as to match the pump power (4000 Liters per hour) that I had obtained for a previous model. However I quickly realized that at every return point of each tube there was no silicone or plastic based hose that was flexible enough to bend around to each connection point.

This wasn’t all disappointing as it meant that I could downsize to 12mm outer diameter tubes with an inner diameter of 8mm and save on cost at the same time. Unfortunately even though I moved down to that size, finding a hose which would fit on the outside of the 12mm seemed impossible.

That is when I decided to try to enter the 8mm inner area of the tube; something considered very unconventional and ‘inconvenient’ but to me this was the only option as far as flexibility was concerned with the materials available to me. I found a 8mm outer diameter silicone tube and it fit perfectly inside.

Step 4: How it came together

Picture of How it came together
IMG_5822.JPG
IMG_5826.JPG
IMG_5829.JPG
IMG_5837.JPG
The trouble now was to sort out the frequency and amount of tubes per rib. I needed enough to cover as much of the surface as possible in order for the algae to capture as much light as possible. I therefore ordered 20 x 1m length 12mm outer diameter tubes. This allowed me enough spacing to double up in the future on the inside if I could raise more money to have a second set under the first set of ribs.

Although at first one pair of tubes seemed easy to connect to each other with the 8mm silicone hose, repeating the process 40 times with such a small radius and a tendency to buckle in and fold on itself seemed impractical. I therefore had to come up with a different system of transporting the algae from one tube to the next. This meant either re-designing the ribs to a much larger scale which would set each tube further apart or changing the tube to an even smaller size which would allow me to purchase an even thinner hose with more flexibility to achieve that goal.

I decided not to go with either, instead I changed the pattern of transport; rather than consecutively going from tube to tube, I would skip 3 tubes on one end and 2 on the other, 3 on one, 2 on the other and so on and so forth. This allowed me to stick with the same design & tubes which were already put together and get a much larger radius which would ensure that the hoses would not pop out of place because of the pressure or their internal positioning in the acrylic tubes

Step 5: The plinth/base

Picture of The plinth/base
IMG_2292.JPG
info-panel-2-Model.jpg
algae-laser.jpg
With the ‘above ground’ part of the model completed, it was now time for the plinth to be constructed which would house all the mechanisms that would operate the model ‘below ground’. The plinth required to place the model on a height which would be comfortable to be viewed by an audience of both children & the elderly but at the same time not be overstated and detract from the model itself.

I decided to make it 1m tall and allow 15cm for each side of the 1m tubes to have space for the turnaround of the hoses. The final dimensions of the plinth were 1m tall, 1,3m long by 0.3m wide.

As this was going to be both an exhibition piece and a University project I felt that there was a strong educational aspect to it. I wanted to somehow be able to tell the story of the algae with this model. I decided to make viewing holes on the rear side which would show the process much like the doughnut company Krispy Kreme has certain stores where the customers can see the production line of how the doughnuts are made from the dough to the glazing.

On these holes I would label what each component would do. Bio-reactor, CO2 pump, air intake, light source. Once deciding on the location of these objects, I decided that rather than having separate holes with separate names, it would be better to have one panel which would be seen as one object containing all the information one needs to know which would be far less distracting.

This turned out to be a really good choice after all and the laser cutting machine did an excellent job. Etching turned out to be much harder than I thought as every letter had to be converted to an object which meant that there was a much higher chance for an error to occur. Each letter had to be checked and cleared of any unwanted lines as well as check for disconnections in the comprising lines.

Step 6: Colour

Picture of Colour
IMG_2355.JPG
IMG_2362.JPG
IMG_2364.JPG
IMG_2367.JPG
IMG_2401.JPG
After that the plinth was ready for painting, a clean white look turned out to be the right choice and a color scheme of white, natural ply & clear proved successful. In hindsight I should have used far less paint quantity on the water tank door as the 3mm ply could not handle the paint and warped. It is purely an aesthetic problem, one that can be addressed after the exhibition is over.

Step 7: Sealing the bio-reactor

With the plinth drying it was now time to seal the tubes and the hoses shut to make a closed loop bio-reactor. I used the super-instant glue rather than silicone because of its ‘instant factor’ and the fact that the hose & tube were such a tight fit that silicone would only create clumps inside the tube and probably cause more problems than it was worth.

When trying to fit each hose in the tubes it was extremely hard to get each one in at first. To solve the problem I countersunk all the tubes in order to get a ‘start’ in each hose so that it could slide in with ease. This was an excellent solution as later I poured glue on the countersunk tube with the hose in place which created a lake which would seal shut. Result: not a single connection out of the 40 connections leaked.

Because the tube was a very small space with a limited air supply, the instant glue would not dry instantly, this created a small puddle inside each connection. I therefore had to try various positions every 5~7 minutes to ensure that each connection would seal on all 360o.

Step 8: Hose fitting

A minor adjustment had to be made to the pumping mechanism. Due to the fact that the 4000 Liters per hour was significantly more powerful than the 15 Liter water tank I was intending to use I had to make an outlet where the pumps power would effectively be cut in half in order to take the stress off all the plumbing connections so they would not suddenly blow apart from the pressure.

The adjustable handle also meant that I could regulate the speed at which the algae would travel round the model and effectively either accelerate or decelerate the growth when needed.

Whilst I would be transporting the model, I would like to have the ability to separate the bio-reactor from the plynth. I used some heavy duty clip-on clip-off fittings which allowed me to completely disconnect the bio-reactor without compromising any connection points.

Step 9: Test Runs

Picture of Test Runs
IMG_2387.JPG
IMG_2386.JPG
After letting the glue settle for 40 hours, the first test run with still water was extremely successful. The air bubbles traveled at a steady pace throughout the model and all the connections held up perfectly. This run lasted for 4 hours. I then proceeded to add algae incrementally over the next week.

Step 10: Growing the Initial algae culture pt I

Picture of Growing the Initial algae culture pt I
IMG_2443.JPG
IMG_6058.JPG
During the building period, I had started to grow algae using the simple method of a water bottle, algae food & the sun. This proved successful in the UK but even more successful in Greece where the sun lasted for longer during the day. I started with a culture sent to me by the Algae Depot of 50ml and after a few days I reached 3 x 100ml travel bottles.

I then proceeded to continue to grow that culture until I eventually reached the required 5.5 Liters after approximately 2 weeks. The algae was growing exponentially quicker due to the limited bottle room I would provide along with excellent sun exposure and feeding regime.

Step 11: Growing the Initial algae culture pt II

Step 12: Test runs

Picture of Test runs
IMG_5991.JPG
IMG_5965.JPG
IMG_6034.JPG
I let the algae run in the bio-reactor for 10 days and achieved excellent results.
Perhaps it was the location of the model posistioned against a window which received very good sunlight both artificial and genuine but it had grown at a steady pace becoming greener every day.

Step 13: Outcome

Picture of Outcome
DSC_6542.jpg
Photo 05-01-2012 18 53 39.jpg
394937_10151120707590408_594310407_21981247_213218056_n.jpg
394916_10151120705135408_594310407_21981216_2092196764_n.jpg
creek-business-card_Front_V2.jpg
Being an ongoing project I do not have the algae biomass output of this experiment yet. 

I will keep you posted through my tumblr blog

http://thealgaeexperiment.tumblr.com/

where any publications results and other events that will be organised shall be posted.

Thank you for looking through this instructable and please contact me if you need any further info.

Charles
1-40 of 56Next »
hirogarden10 months ago
what kind of pump was used in this system? I have been trying to think about it for a while now and not sure what could pump water, air and the small solid algae. I attempted to send an email to the mouchmouch@mouchmouch.com a few days ago and have not heard anything back. I wanted to attempt to build something like this but scaled up a bit but have been unable to think of a pump or search for one online that I think would accomplish the task of pumping air water and small solids.
InTheory1 year ago
Nice report I hope to make something like this one day. I plan on trying to mix this with another instructable (http://www.instructables.com/id/Food-of-the-Future-Window-DIY-Spirulina-Superfood/) to make an indoor oxygen scrubber, and food source. Who knows maybe it can even be used in fuel useage, but I will have to research more.

I was thinking of getting a UV tube light, a 3"X(uv tube)" and a 5"X(uv tube)" lengths of plastic (UV resistant) or glass pipes. With a mirror to reflect any excess light. The bubblier for CO2 at the bottom and O2 extracter at the top (I will need to look into this). Any reason this shouldn't work? Why are you using a series of small pipes instead of one large tank? Should I base a design off of a series of smaller pipes instead of one sheathed tank?
mcipriano2 years ago
Have you been able to make any algae biofuel?
White_Angel3 years ago
This is all very new to me and quite exciting! My only concern is that the power to extract the usable oil seems to run the gamut in power consumption making it a moot point. Unless it is possible that the biofuel is so efficient that it could produce enough power for the extraction process and then some I don't see how this is applicable as a long term solution. Does anyone know the relationship between the amount of energy needed for extraction and the amount of energy produced per unit of Algae based biofuel?
Malkaris3 years ago
Pretty slick, did you consider just using a continuous length of tubing for the top part? Instead of the sold-flexible connections just "laced" the whole thing with one continuous piece?
what application can this be applied to? i mean, why would i want to build something like this?
m0uch (author)  golddigger15593 years ago
Higgs is right, through processing the biomass you can get a new form of fuel essentially.

If you would like to read more I have published a paper on the whole project on issuu.

http://issuu.com/mouchmouch/docs/thealgaeexperiment
wblack3 m0uch3 years ago
Beautiful looking report!

I've been looking at using the extracted algae oil (and any other cheap and/or waste veg or animal oil/fat triglyceride) as 'green diesel', different from 'biodiesel'.

Biodiesel is typically fatty acid methyl ester (FAME), made by reacting veg oil with lye (hydroxide) and methanol, yielding stuff that can be used in place of diesel fuel. Advantage: easy to convert in a backyard barrel, good lubricating properties; Disadvantage: can 'gum up' due to other double bonds elsewhere in the fatty chain, like varnish, thus destroying most fuel injectors, pumps, etc. Also, a more powerful solvent than regular diesel, so need viton fuel lines, gaskets, etc., and better fuel filters because the FAME tends to dissolve all the crud in the tanker, storage tank, transfer lines, your fuel tank, sending all the gunk straight to your filter, or worse, injectors. Nasty.

'Green diesel' is diesel made from renewable sources like veg oil. Can be made by hydrotreating veg oil using a Ni-Mo catalyst at maybe 300'C and 50 Atm pressure, not unlike making margarine, but more so. Adv: very high 'cetane' rating (like 'octane' for petrol / gasoline) at maybe 95 cf. 'regular' diesel at 51 cetane rating. Can therefore be used to blend into low grade diesel. Hydrotreating with hydrogen gas can fully saturate double bonds in the fatty chain that would otherwise lead to gumming up.

Oh, yeah, great that you're using the natural floatation of the algae to enrich for species / strains that yield lots of oil and oxygen! Ideally the whole reactor tube system would use both the thermosiphon effect (heating up on exposure to sunlight) and the decrease in cell density due to oil and gas accumulation to help circulate the algae through the pipes.

Keep us all posted on how it's going, m0uch!

PS, would it ice up in winter over your way?
jexter wblack33 years ago
Hi wblack3,

Lots of good additional information for an already great Instructable - thanks!

I was wondering about people running used fryer oil from restaurants in their diesel powered cars; as I understand it, all they generally do is filter it to remove food particles. From what you say, though, it seems that if they used fresh veggy oil they would run into problems. Is the fryer oil actually improved because it's used? I'm guessing something like the high heat and the H2O boiling off from the food while it's cooking is doing something to modify the oil's composition? If so, that's pretty cool that you get two uses out of a renewable resource, with the first use improving it for the second use! (Unlike diesel, which no one wants their fries boiled in :-)
wblack3 jexter3 years ago
Hey, Jexter,

I had to look it up. It's funny, what they told me at uni years ago was that fats/oils get hydrogenated or at least lose their polyunsaturated 'goodness' after being heated for a while... i.e., used for cooking.

So my lecturer in biochem reckoned that polyunsat oils were really no better than sat fats like palm oil, coconut oil, etc.

However, this was at odds with what I also knew from chem eng in that hydrogenation, to be efficient, requires higher temps (300'C), pressures (2.5 atm), H2 gas, a catalyst like Nickel or Copper complexes on a silica or alumina (or both) support (really just wee ceramic beads usually).

Here! http://www.brevardbiodiesel.org/iv.html

The Iodine value is an indication of how unsaturated the oil is, and usually equated with how unstable it is, but others have indicated this is not always the case. An unstable oil is not what you want to put through your high pressure common rail fuel system and injectors, esp. if running a sweeeeet sweet VW golf series5 2.0 L TDI... as I am ;-)

The common rail system gets up to over 1000 atm, a recipe for all sorts of chemical craziness to bust out.

Does look like the longer an oil is used for cooking, the more 'burnt' and partially oxidised it normally becomes, but not nec. a great reduction in the double-bonds that are the 'unsaturated' or high Iodine number factors that I thought would lead to chemical unstability, gelling, gumming of the injectors, burning / coking of the injectors and cylinders, etc.

Personally, before I stick it into my sweet ride, you test it on yours and let me know how you go (and IF you go) ;-)

Otherwise, I've been toying with the idea of using hydrogenation reactors and Ni-Mo catalysts to clean up algae oil, waste veg oil, grease trap gunk, and turn it into chemically stable fully saturated and low S, O, P, N oil more like petroleum derived diesel, or 'green diesel' rather than 'biodiesel' fatty acid methyl esters (FAME).

W
well for one thing algae produces natural gas that can be used instead of fossil fuels.
I was actually planning to do just that for my Google Science Fair entry. Do you mind if I use your bioreactor in it? I'll credit you for the design.
True but I have a feeling this educational model is to illustrate how we can convert algae to biofuel because of the high percent of oils in the algae. Although, the harvesting techniques available make this process not economical. Hopefully someone will figure that part out soon.

Cool model, and nice instructable! could you share a little more on why you made this bioreactor?
m0uch (author)  sffitzge3 years ago
Hi sffitzge, thank you for your comment. Yes the harvesting techniques are still being worked out, there is some great work done by a company called origin oil where they use a process called ultrasonification to separate the lipids for oil extraction. I made this model as part of my Architecture MA, it's a prequel to my Graduate Diploma project which you can find a summarised version of here:

http://issuu.com/mouchmouch/docs/fuelcartridge

Overall I wanted create a piece which would be able to show people that anyone could start growing algae for the purpose of bio-fuels at home. This is not to say that it's either easy nor 100% feasible however it did provide food for thought for the people who attended the exhibition which I hosted in the UK.

I know the extraction part is the 'hardest' part although growing the algae in large, effective quantities in itself is the first step..
Question?

Could the algae and their byproduct not be used as a free fertilizer? I assume that the algae would be a great form of biomass and the natural gas byproduct would be full of nitrogen?

Instead of fueling a car your fueling your home garden.

Please let me know if i'm out to lunch or bang on?

If i'm right I guess this is food for thought?
Thanks for the replies, interesting to know
m0uch (author)  derekvpierce3 years ago
Hi Derekvpierce,

Yes the algae can be used for diverse reasons, although once used for its oil extracting purposes it can also be used as something else, usually livestock food because it is rich in nutrients. However, as I am not a scientist I cannot confirm about your nitrogen query. I will look into it and reply back.
oz93666 m0uch3 years ago
Algae cannot 'fix ' nitrogen from the atmosphere (Google 'fix nitrogen') ,so the only (soluble) nitrogen you get out is what you put in from the fertilizer used to run it
wblack3 oz936663 years ago
As above, Anabaena can fix N under the right conditions, but those conditions of low N may end up being quite limiting overall.

Use of human wastes and effluent could work, but tends to have too much Sodium and not enough Potassium. Use of a worm farm and composting from garden, market and agricultural waste can work, but does require manual labour and quite a bit of tricky balancing.

In New Zealand, they're using an algae reactor to treat sewage, but will have to wait to see the results in a year or two. Sometimes these things seem OK to begin, but can 'wash out' over time, being overgrown with non-productive organisms, or even 'predator' organisms like Amoebae.
this device requires an INPUT of fertilizer to function , its growing plant material. From a practical point of view its a non starter , only sensible for growing spyrallina for human consumption.
aröder3 years ago
Is it possible that a setup like this could be used for bioremediation. Could one use it to purify greywater or even sewage?
wblack3 aröder3 years ago
and http://www.asiabiomass.jp/english/topics/1109_03.html
wblack3 aröder3 years ago
Yep.

http://www.niwa.co.nz/publications/wa/vol13-no4-december-2005/energy-from-wastewater-treatment
So you grow the green stuff... Then what? You grow the green stuff for?
Soarak3 years ago
Excellent project, have you considered adding an active yeast culture on a carbohydrate feeding regime to provide CO2 to the algae?
Dantex Soarak3 years ago
I can't really say from experience, but I believe that it wouldn't be much good
as yeast requires sugar to crate CO2, and in that process it creates alcohol, witch would probably harm algae
Soarak Dantex3 years ago
You're completely correct. To remedy this all you would need to do is add a separate holding tank for the yeast with a vent lent and and an air diffusing stone used in fish tanks to allow the CO2 to rise up (though it's about 1.5 times the weight of air, the volume created should be enough to force it's way out like a soft drink) out of the yeast and through your line into your tank. Furthermore, honey is an excellent source of both yeast and carbs as food if you get it from an apiarist somewhere locally before it has been pasteurized for general consumption. As a side note, yeast like the dark so you could hide the ugly tank somewhere in a cabinet away from judging eyes. Just a suggestion .... I'm not sure about the returns of CO2 from an active yeast culture vs. the amount of time, space and money for feeding said culture but might also be an interesting experiment to play with......
Dantex3 years ago
You got me interested in this project so i want to try it on my own
but during research I found that Schiochytrium algae would give higher theoretical yield
why aren't you using that algae?
m0uch (author)  Dantex3 years ago
Hi Dantex,

I never came across this strain of algae that you are referring to. However the reason I chose B. Braunii is because from the location I procured the algae from it was either that species or the N.Occulata species and the Braunii typically has very high oil yields as it is. I am in talks though to obtain more strains of algae in order to do further testing. I will look into the Schizochytrium strain. Thank you for the information.
Dantex m0uch3 years ago
Thanks for reply!
I am starting my bioreactor very soon =D
I am wondering about he design - Wikipedia refers to it as "Tubular photobioreactor", but also it says that it is rather inefficient (when you think about it it is logical as most of CO2 gets used up in first tubes)
so I am trying to avoid that problem, maybe if the air is introduced in multiple points?
Anyway for beginning I believe I'll start with "Bubble column bioreactor"
wblack33 years ago
Beautiful looking reactor. Great photography of it, too!

Elegant solution as to the placement of the tubes to get maximum solar exposure.

Yes, there is some interest in using microalgae to produce oil for biodiesel / green diesel and cosmetics/pharmaceuticals, with the algae cell debris pellet for use as cattle feed. The advantage being that it is some thousands of times more efficient per hectare land area at converting CO2 into biomass than current plant crops. Also, given it is inedible, it does not compete in the 'food-or-fuel' dilemma discussed of palm oil.

Check out MBD Energy for the biosequestration of CO2 from coal fired power station emissions.

Actually, some microalgae *do* fix nitrogen under some conditions, mainly low nitrogen, forming 'heterocysts' or lumps to keep out oxygen that otherwise stuffs up the N fixing enzymes. Anabaena is one http://en.wikipedia.org/wiki/Anabaena.

Also, one can extract the oil then compost the cell debris and 'recycle' the inorganic nutrients like N, P, K, S, Fe, Mg, etc., but yes the use of fertiliser is a significant energetic input considering about 1% of the world's energy consumption is fixing N via the Haber process.

Er, also, one problem that many algae species suffer is that they don't like really bright light. Ironic, eh?

This might not be such a problem after a couple of weeks of operation as the insides of the tubes will be coated with biofilm and gunk anyway, so it will reduce the amount of light reaching the algae. Use of silicones like silcote can make the insides of the pipes less sticky.

Use of a small solar PV cell to power your pump is good, as also setting it all up as a solar thermosiphon to minimise power consumption from pumping water through a narrow pipe.

Good work! I might give it a go myself!

W
m0uch (author)  wblack33 years ago
Hi wblack3,

Thank you for your comment, I hope you do give it a go, I would love to see the result :) Yes you are correct about using the solar PV cell to power the pump, the only reason I did not use it was because of funding issues.

Let me know if you need any help.
Charles
The connections you made using brass may be better if plastic was used since copper is an algicide and will somewhat inhibit the growth of algae
I remember something about getting Hydrogen from Algae by growing in a Methane inviroment, forgive me if my info is off Maybe due to failing memory. I pretty sure the artical mentioned experiment fail at first because they had an issue with Oxygen contamination I wish I could have saved the artical. Anyway, the algea would digest the methane and produce Hydrogen
photis223 years ago
I've been working with algae for 4 or 5 years now and I haven't seen anything quite like this, the design is quite excellent, I'm impressed.
rcisneros3 years ago
I have to say.... Impressive.
tcarney573 years ago
Extremely creative project! You are one of the "they" people talk about when they say, "oh, someday *they* will solve that problem." Unfortunately, it's usually used as an excuse to keep on wasting non-renewable resources.

Years ago I sketched out an idea for what I called a "Human Nitrogen-Recycling Reactor" (HNRR). Essentially, the idea was to convert human urine into usable nitrogen fertilizer.

For several thousand years, Chinese farmers and gardeners would pour their urine into a barrel to let it "ripen." They would then pour the fertilizer on their intensively-gardened plots. The Chinese who came to California during the Gold Rush, using the same pee barrels, found they could make more money by selling fresh produce, intensively gardened and piss-fertilized, to American miners, some of whom were known to spend a day's worth of gold on a single egg or head of collard greens.

My HNRR would run as a semi-closed system so that the volatile ammonia (readily detectable by the nose) would not be lost. Instead it would be redissolved back into the "effluent" (a reasonable euphemism for piss). The effluent would then be cycled through a medium (plastic balls, gravel, etc.) in which dissolved ammonia would be converted to usable nitrate by ammonia-eating bacteria that naturally take up residence in the medium.

The use of ammonia-loving bacteria (to each his own, I suppose) is the core of the process. That's the already well-proved part--it's how ammonia (toxic to fish) is converted in ordinary aquarium filter pumps to better-tolerated nitrate.

In the HNRR, at some point (not all that long) the batch of piss would be fully reduced to garden-ready liquid fertilizer.

Two issues I never got around to resolving. The first was more psychological than real: it's urine (!!) so how does it not present a health hazard? Tests would have to be made, but frankly I think the high levels of dissolved ammonia present at the beginning of the process would sterilize infectious bacteria and viruses. Those are not typically present in human urine anyway except in the case of an infectious disease such as a cold, flu, or obviously, an infection of the urinary tract.

The other issue was that the reactor would run, by it's nature, in a batch mode rather than a continuous one. That would complicate using the thing. Do you store the pee before running a full batch? Maybe. To make the process continuous end-to-end---dump piss into one end as it's produced in the household and collect converted liquid nitrate fertilizer at the other end--would be a real challenge. It would certainly make the HNRR more complicated (and costly).

I suppose another issue would be how to collect the urine. Chamber pots? Empty milk jugs?

You know, I might just dig out my notes on all that. Nerds like me keep things like that. Thanks for the inspiration!

Todd
Write an article about it. Would love to see it.

I'd say collect and pour in till the first batch container is full. Have a few reactors going at the same time. Distillation and crystallization would be an interesting challenge to get solid nitrates. Though separation of the nitrates from the phosphates and other minerals might prove to be a bit of a challenge as well.

I've tried collecting mine for other experiments and have found that milk bottles and Powerade/Gatorade bottles are good to since they have a larger cap and mouth. Makes for an easier fit and less splashing.
flyingpuppy3 years ago
Here's my algae bio-fuel system: a backyard pond with black plastic lining and a willow tree next to it that drops leaves in the water which degrade into food for algae. Now all I need is to figure out how to turn the algae into fuel!
mostertbj3 years ago
Apart from the science value of this experiment, I bet you'll be able to sell this model as a "mad scientist lab prop" once you decide to go bigger ;-)
1-40 of 56Next »