Home About us Contact us Search Permaculture Blog Composting » DIY Projects » Energy & Water Gardening » Worms » Biogas Digester April 20, 2012 Main Article Tweet 1 “Biogas is the perfect solution to modern sustainable cooking.” Biogas is a mixture of gasses that are produced as anaerobic bacteria break down organic matter. It is flammable, capable of producing a clean flame for cooking and heating, and it can be derived from as simple a feedstock as your kitchen rinse water. A biogas digester is a container holding water and bacteria, which can be ‘fed’ organic matter to be broken down, and which collects the resultant biogas, to be tapped off either to a collector for storage, or directly for burning. Benefits: Creates flammable gas Creates fertiliser Runs on kitchen rinse water 2/13/2013 Biogas Digester | Shaun's Backyard - Wh… shaunsbackyard.com/746/biogas-digester/ 1/26
“Biogas is the perfect solution to modern sustainable cooking.”
Biogas is a mixture of gasses that are produced as anaerobic bacteria break down organic matter. It isflammable, capable of producing a clean flame for cooking and heating, and it can be derived from assimple a feedstock as your kitchen rinse water.
A biogas digester is a container holding water and bacteria, which can be ‘fed’ organic matter to bebroken down, and which collects the resultant biogas, to be tapped off either to a collector for storage,or directly for burning.
Benefits:
Creates flammable gasCreates fertiliserRuns on kitchen rinse water
200L blue plastic barrelsplastic garbage binPVC pipes and fittingsPV hoses and fittingsSilicone sealer
Jump to:
PlanningDesigningFilling my Biogas DigesterFeeding my Biogas DigesterBurning BiogasEmptying my Biogas DigesterSummaryFAQ
What else can I use to make a biogas digester?How much scraps for how much biogas?Will the biogas collector explode?
Related ArticlesIntegration
Planning
In March 2011 I set about designing my own home-scale biogas digester, and biogas collector, using 200L (44gallon) blue plastic barrels. It was my aim to create a system capable of producing enough biogas to cook onemeal per day, and therefore become the dominant energy source for cooking at my home.
Design for my biogas digester, collector and burner
A friend of mine had collected a number of 200 Litre blue plastic barrels from a local hospital, which had beenused to store cleaning chemicals. They were sealed, with two screw-in lids at the top, and a slight dome shapetop which became an important factor in my design.
The input pipe, gas-out valve and output pipe all fitted to the top of thebarrel
A biogas digester requires an input pipe (a place to deposit fresh feedstock), and an output pipe of some kind(for contents to be displaced out of). Since there were already two screw-in lids which sealed perfectly, Idecided to take advantage of them, and designed that both my input and output pipes should enter the barrelthrough the top of the barrel, through the lids, and the biogas output should also be located at the top of thebarrel.
A prototype digester and collector, using vinegar and bicarb soda toproduce and collect gas
My design was different to others I had seen, and I wanted to be sure it would work, so I created a prototypebiogas digester and collector using plastic bottles and straws. I mixed white vinegar with bicarb soda to create(rather quickly) carbon dioxide gas, to test how the physics of the system might work. This gave me a goodplatform of understanding, and I felt more confident to trial my design using the blue plastic barrels.
My biogas digester was designed to be gas-tight, so that no biogas could escape the unit except through the gas-out valve, which was a simple polytube irrigation valve. However, if for some reason pressure should build up inthe system, it would simply push the contents out through one or both of the input/output pipes.
The input pipe ran through one of the lids of the blue plastic barrel, and extended almost to the bottom of thebarrel. This meant that fresh feedstock would enter the digester at the bottom. The output pipe ran only to thecentre of the barrel, which meant that as fresh feedstock entered, existing liquid would be displaced from thecentre of the barrel, and exit the unit into an effluent bucket. Since solid particles of organic matter usually eitherfloat or sink, it would be mostly only liquid which comes out as effluent, leaving the larger particles in the digesterto break down further.
The pink line shows the water level inside the digester. Note the gas-outvalve is above this level
I was able to set the output pipe almost at the level of entry into the barrel, which left a pocket inside the dome ofthe top of the barrel for biogas to collect, and it was at the very top of the barrel that I fixed my gas-out valve.This meant that at any given time there would be very little biogas stored in the digester – the digester would bealmost completely filled with liquid, and almost all biogas would be expelled via the gas-out valve to the collector.
The collector (empty) is an inverted plastic garbage bin submerged inwater
The collector was simply a blue plastic barrel with its top cut off, 3/4 filled with water, with a plastic garbage bininverted and submerged, with a gas input and a gas output valve fitted to it. Biogas produced by the digesterwould collect in the garbage bin, and as the garbage bin filled, it would rise out of the water. If the unit becametoo filled with biogas, biogas would simply leak out the side.
Filling my biogas digester
I filled my biogas digester with water and about 20kg of cow manure. The idea is to breed the various kinds ofintestinal bacteria from the manure, so that they can process feedstock the same way they do in a cow’sintestines – breaking it down into fertiliser and creating flammable gases. It took a week or so for the bacteria tosettle in and begin digesting feedstock.
As I pour kitchen rinse water in, effluent is displaced into a bucket whichgoes straight on the garden
Feeding my biogas digester is easy. I shut off the gas-out, and open the lids on the input and output pipes. As Ipour my kitchen rinse water in, an equal volume of effluent pours out into a bucket, which I then take and pourinto my garden.
Biogas is fart gas, the same as what a cow produces! It smells as you’d imagine, but when it is burnt the smell isthe same as from a clean natural gas burner.
Burning biogas pure (L) and mixed with air (R). The blue flame is cleanand hot
Burning biogas alone produces a large yellow sooty flame, which will turn the bottom of pots black, and will notheat very efficiently. It is when air is allowed to mix with the biogas just before it is burnt that a hot, clean, blueflame is produced. For this I created a bunsen-burner, to test the variables involved.
The holes allow air to mix with the jet of gas, after it passes through arestrictor
Gas restrictors made of wood. These force the biogas into a jet stream
My bunsen burner is made from scrap pvc pipe, a spare polytube sprinkler fitting, and some circular woodendoweling fashioned into a gas restrictor. I made a few of these restrictors with different sized holes to experimentwith, and drilled holes through a pvc collar into the main pipe, which allows air to enter and mix with the streamof biogas – also the collar can be rotated to limit air flow. It took me a few tests to find the most efficientcombination of factors to get a nice hot flame.
A classic gas bbq, with biogas connected. A single clean flame heats a potof water
I attached my home-made burner to the bottom of an old gas barbecue. Using the existing supports I can cook ina pot over the biogas flame. I place a weight of either 5kg or 10kg on top of the biogas collector bin to applysome pressure to the biogas. The 5kg weight allows for a modest flame capable of boiling a litre of water inabout 15 minutes. The 10kg weight forces biogas out quicker, and a litre of water can be boiled in 10mins.
Emptying my Biogas Digester
During it’s first winter, I gave my digester diarrhoea! I had been feeding it fermenting/mouldy bread and I poured
in some bokashi juice too. The bacteria inside the digester became unbalanced, and the wrong kind took over.Biogas production ceased and the effluent smelt like sickly diarrhoea. I decided I had to empty it and start over.
Most digester designs include a ‘sludge-out’ pipe toward the bottom, but mine does not have this. I developed atrick to displace most of the contents of my digester, so that the unit can be moved and emptied easily.
I disconnected the gas hose between the digester and the collector, leaving one end attached to the digester. Byblowing into this hose, the pressure forces effluent out into the effluent bucket. 5L at a time I emptied bucketloads of diarrhoea into the garden. Since the PVC output pipe only extends halfway down the height of thebarrel, I was only able to displace half the contents in this way, which left approx. 100L left in there. At this pointa hand trolley could be used to shift the unit. I didn’t have a hand trolley, so I swapped the PVC input funnelfittings for the output pipe fittings and kept on blowing. Since the input pipe extends almost to the bottom of theunit, I was able to expel everything but the sludge at the bottom. Now I could unscrew the input and outputpipes, and the gas-out valve and tip the barrel upside down into the garden. I used the ‘jet’ function on the hoseto blast the sludge off the bottom.
I even went to the extent of flushing the barrel with eucalyptus oil and detergent, to clean and disinfect the unit.After much slushing and rinsing, I returned the unit to its corner and refilled it with cow manure and water. Biogasensued for a couple of weeks, but the unit contracted diarrhoea again! It was still winter, so I’m not sure iftemperature had anything to do with it. I gave up on my digester and left it. After some weeks of neglect, Inoticed my collector had risen. I did a flame test and confirmed biogas was being produced. I checked theeffluent and it smelt like good ol’ fresh cow manure again! I was back in business. I still don’t know exactly whathappened, but the bacteria sorted itself out.
My biogas digester project was successful; the digester is capable of producing more than 30mins worth ofbiogas per day, and the collector can just hold this amount of biogas. However, I have decided not to go to thetrouble of grinding/chopping/blending/mincing up kitchen scraps to fully feed the digester, and have instead beenfeeding it the rinse water from my kitchen which amounts to about 4L per day – a mix of water, liquids and foodparticles from rinsing cups and plates. From just this feedstock I have been generating about 15mins worth ofbiogas per day – enough to steam some vegies in the morning and make a cup of tea.
My system is limited by the collector – it can only store about 30mins worth of biogas, while the digester itselfcan produce more than double this if it is fed substantially. For my purposes, a larger collector is unnecessary,but I encourage anyone planning to do all their cooking on biogas, to consider multiple collectors or scaling upusing larger containers.
Frequently Asked Questions
What else can I use to make a biogas digester?
Any large plastic container is fine. Do not use steel drums nor any metal parts for your design, as the hydrogensulphide component of biogas will quickly corrode these parts. So far I’ve seen no deterioration of any of theparts I’ve used (PVC, Polyvinyl, Polyethylene) in contact with biogas and/or effluent. Consider olive barrels, orfor a larger scale digester consider 1000L tanks (with cage).
If, today, you ground/minced 1kg of mixed food scraps, and poured it with water into a digester, 24 hours lateryou would have enough biogas to cook for an hour. The next day you would still be collecting gas from thisfeedstock, so there is an overlapping return as you feed each day. I personally choose only to feed my digesterthe rinse water from our kitchen, which is about 4L per day, and this yields enough biogas to boil 1L of wateronce per day – enough to make tea or steam vegies. If I don’t cook on biogas one day, the next day I haveenough to cook pasta or rice.
Will the biogas collector explode?
No. To explode your collector you would need to 1: mix air into the collector, 2: put the collector under pressureand 3: somehow create a spark inside. If for some reason you feel that these three events would occursimultaneously with your biogas digester, I recommend you do not persue this project. My collector is gas-tight,only under pressure when I’m cooking, and I couldn’t create a spark in there if I tried.
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Integration
“Involve different technologies into your backyard, by integrating.”
bacteria, Burning Biogas, FAQ, kitchen scraps, water
32 comments on “Biogas Digester”
1. Mokhele on July 10, 2012 at 8:32 pm said:
is there no gas flowing out through the outlet to the bucket together with the effluent?If no,how do youstop it from flowing in to that output but to the correct gas output?thanks
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Shaun on July 10, 2012 at 10:05 pm said:
Hi Mokhele, thanks for your question. I think you are asking if biogas is escaping through theeffluent out. It is not possible becuase the effluent pipe goes down into the digester, about halfway.Since the gas bubbles up to the top of the digester, there is no chance for it to escape. I hope thismakes sense. I was not certain, so I did a test using bottles and straws.
2. Rahul dhawan on September 21, 2012 at 6:04 pm said:
Hi sir how are you. I made biogas plant if 100 m3 capacity of plant . I want to use as a small genset forelectrifity. I want clean biogas by removing g2s from biogas.could you please help in this matter. Thanksrahul dhawan
Reply ↓
Shaun on September 22, 2012 at 2:25 am said:
Hi Rahul,
100m3 is a huge capacity! I have only learnt enough to make a home-scale digester (approx 1m3).I’m not sure what ‘g2s’ are. Biogas is made up of Methane, Carbon Dioxide and a small amount ofHydrogen Sulphide (which will corrode metal). If you want clean methane gas, you must take fromthe top of your storage (methane is lighter than CO2), and pass it through a ‘scrubber’, which is apipe filled with steel shavings. The steel reacts with the hydrogen sulphide in the gas, then you willhave pure methane. You can also bubble biogas through water which will react with CO2 to formcarbonic acid, but this will require more pressure, and you must change the water regularly.
I hope this helps.
Good things,
Shaun
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3. chan on November 10, 2012 at 10:10 am said:
nice design,im planning also doing this however with 3 gas holders.
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Shaun on November 29, 2012 at 1:15 pm said:
Hi Chan, thanks for commenting.
Good luck with your design, and let me know how it turns out – I would like to add a gas collectoror two to my unit someday.
Hi Patrick. A biogas digester must contain water, feedstock (food scraps), bacteria (from manure)and very little oxygen (sealed container). If you have all of these ingredients at room temperature,you will produce biogas. Good luck!
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5. Senthil Kumar on December 8, 2012 at 12:15 pm said:
Shaun, very simple and informative article!
I have a couple of questions. I am trying this in a miniature scale to see if I can produce gas at all.
I am adding about 200 – 300 grams of mixed food and veg waste to a 2Litre bottle and fill it up withwater to the top. I have a small tube with a valve attached to the cap (air tight). Here it is very sunny, sotemo wouldn’t be a prob.
1) Will this mixture work by itself? Or do I have to add manure like cow dung to start it off?
2) I would like the gas it produces to burn for at least 10 seconds as proof that it worked. Will this setupproduce at least such an amount of gas in 24hrs? If not, how long will it take?
3) I do not intend to setup a secondary collector for now. I am going to let the 10second worth gas collectat the top of the digester bottle itself and release it and test it. Once it works, I plan to make a larger scalemodel with inverted bucket type collector. Do you think this will work for demo purposes?
Thanks!
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Shaun on December 8, 2012 at 12:53 pm said:
Hi Senthil,
There are only some kinds of bacteria which produce methane gas. They are called ‘methanogens’and they exist in a cow’s gut and also in other animals guts (even human). Manure is added to themix to introduce these bacteria to the system. Without manure, other kinds of anaerobic bacteria
will consume your food scraps, producing other gases which may not be flammable (such as CO2).If you don’t add manure I cannot guarantee success!
Also, even if you do mix manure into the bottle, I cannot guarantee you will have flammable gaswithin 24hrs! There is a series of breakdown processes which occur before methanogens startworking (yeasts ferment the food, making alcohols, acetogens turn alcohols into acetic acid,methanogens take acetic acid and produce methane gas). Digesters can take up to 2 weeks toproduce methane. Up until then mostly CO2 is produced.
I guarantee your project will work if you 1: mix cow manure into the bottle, 2: feed it a smallamount to begin, 3: try burning the resultant gas each day until you see a flame. It could take aweek.
Finally, remember that biogas burns better when it’s mixed with air.
Good Luck!
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6. Senthil Kumar on December 9, 2012 at 12:16 pm said:
Hi Shaun,
Thanks for the information! I have created my setup, just waiting for manure; tough to find here in the city:D
I plan to add 200g fresh manure + 200g veg and fruit waste. With some water for mashing them up, thisshould occupy about a litre. (Unfortunately, this is all the biomass I can get at the moment).
I’ve decided to use a 20L bottle now. To remove air completely, I am going to fill up the rest of the 19Lwith water. Will this level of dilution cause any problems, other than possibly lower or slower yield?
Reply ↓
Shaun on December 19, 2012 at 12:36 am said:
Hi Senthil, sorry for the delay,
If you cannot get cow manure, you can use humanure for your digester. I know, it’s a strangethought, but actually it is fine, so long as you are not sick at the time!
You should know that methane gas is lighter than air, and air is lighter than co2. It’s likely then thatmethane should collect at the top of your container.
Water is not a problem at all. The bacteria are ‘hydrophilic’, which means they love water, andoperate well in water.
Will you be collecting your biogas in a separate collector?
Good things
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Senthil Kumar on December 19, 2012 at 11:23 pm said:
Shaun, no problem!
Yes, I’ve changed my plans; Now, digester is 20L bottle. Collector is a 1L bottle invertedon top of a 2L bottle containing water.
I am thinking about the humanure thing; I am okay with it. But I’m wondering how my familywill react, once they get to know what’s inside the bottle :D psychological thing. hehe.. :) Butwe have absolutely no problems with cow manure because handling it for householdpurposes has been part of our tradition for 1000s of years!
I guess I am in a good position to get started now. Thanks for the help! I’ll let you know howit goes and post pics if possible.
Cheers.
Reply ↓
7. Gaudencio V. Garcia Jr. on December 17, 2012 at 8:55 am said:
Hi Sir, your design is so nice and simple. It could be understood by almost everybody.
Reply ↓
Shaun on December 19, 2012 at 12:25 am said:
Thank you Gaudencio!
Reply ↓
8. Azmat on December 20, 2012 at 2:44 pm said:
Hi Shaun: I have just made a biogas digester based on your design. Just yesterday only i have charged itwith cow dung and some rinse water. How much time it will take to produce gas after charging. I justwanted to know besides rinse water what else can be used as feedstock for the digester and what things ishould avoid to put in. Also there is a little more space left in the digester after i charged it with cow dungand rinse water. is it okay to leave small amount of oxygen in the digester?
Thanks for your questions. They say it can take up to 3 weeks for a digester to start producingbiogas. However, I had flammable gas 10 days after I filled my unit. I filled mine with one bag(20kg) cow manure and almost to the top with water. I started feeding it rinse water, which wasabout 4L per day, and I watched the collector for rising. First, co2 was produced, then biogas, sokeep testing your gas with a flame until you see it burning. You don’t have to add anything to beginwith – the manure and water will produce some biogas. The temperature will also affect theefficiency (warm temperatures work best)
You can feed your digester much more than just rinse water. Rinse water gets me a ‘hobby’ amountof biogas – enough to boil some eggs and make a coffee each day, and it’s easy to collect and pourinto the unit. You can grind up all your kitchen scraps, including bones, rotting meat, expired milk orcheese – all of the above. I have seen devices which fit under your sink drain and grind up anythingthat goes down. It’s best to mix the grindings with water and pour it into your digester. If you dothis you will get far more gas – enough to cook on every day.
If you decide to add ground/solid foods to your digester, you must be prepared that a sludge willbuild up at the bottom which will eventually block up your input pipe. Some people create a‘sludge-out’ pipe at the bottom to empty their digesters. After more than a year of adding only rinsewater to my digester, I haven’t had any problems with blockage (although I do add coffee grindswhich might build up).
The only thing I would caution a person not to put in a digester (though it may seem like a goodidea at the time), is bokashi juice. I poured some in my digester thinking the anaerobic bacteriamight add to the digestive bacteria in the system. My digester promptly stopped producing biogas,produced a big swell of co2, then the contents turned to diarrhoea!!! Those were dark times, andnow I keep my bokashi buckets separate from my rinse water buckets.
Finally, your digester will work best if it is filled with water (and some cow manure), but it doesn’thave to be 100% full, just so long as the pipes for input and output are submerged. You can beadding material for a while before the unit fills up and effluent starts displacing out. No problemo!
Thanks for your detailed reply. I am now assured about my charging of the digester and if mydigester is successful in producing the biogas all the credit goes to you, who designed theunit, and i have just implemented it based on it. Right now i have stopped feeding the digesteruntil it rises with biogas. Being winter here it may take a bit more time than usual, but i willkeep you informed how my digester is working from time to time and to get your inputs inmanaging it.
I thank you again for your help and see you soon.
RegardsAzmat
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9. Mounes on December 27, 2012 at 5:23 am said:
Hi Shaun,Thank you for your article. can we use poultry manure instead of cows or other mammals? do we need tohave the manure fresh or we can use dry one?
Reply ↓
Shaun on January 4, 2013 at 6:36 pm said:
Hi Mounes,
Yes you can use chicken/poultry manure for your biogas digester. You can also use cow, pig oreven human manure (humanure). I started my digester with cow manure which had been in a bag inthe sun for a long time. It wasn’t completely dry, but almost dry. I don’t think dryness kills bacteria– they just go into stasis and wait to be moist again. I’ll bet your system will start fine with drychicken manure. Let me know if it does!
Reply ↓
10. sabari on January 4, 2013 at 8:36 am said:
Hi sir
What the reason to collect bio gas in separate barrel with water? Any reaction to be take place there….clarify me..
The main reason for storing biogas separately, is so the system has no smells. We have it rightoutside the house, and there is only smells when I feed the digester. There are some designs whichhave the collector bin inside the digester, but you will see the bin rise up with scum all around thesides. Flies would also be attracted to such a system. Also, having a separate container means thecontainer can be larger, or there can be many containers storing gas from one digester.
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11. Gustav-Adolf Schildt on January 9, 2013 at 1:46 pm said:
Good day Shaun,
I do like the design as it is a solid drum and there will be no scum on the sides as you said.
I have only one question to gas tightness. As the blue container has only 2 “Bung Tops” on top how doyou make the gas outlet valve gas tight? You can’t put your hand in the drum. Do you cut a 1/2 inchthread in it?Cheers,Gus
Reply ↓
Shaun on January 9, 2013 at 2:33 pm said:
Hi Gus,
Thanks for your question. I’m not sure how standards vary for irrigation parts around the world, butI used a simple adaptor piece to screw into a hole I drilled in the top of the barrel, which thenallowed the ‘gas-out’ valve to screw in nicely. The adaptor piece had a lip on it, and I was able tofit a rubber ring underneath the lip, such that when I screwed the adaptor into the barrel, the ringsealed it airtight.
A couple things for your to consider. Since the gas is not under any pressure, a true gas-tight seal isnot essential. Even sticky tape will allow you to test your digester. Also, if your parts are not exactlycompatible, silicone can be used to seal all your seals. I had PVA glue first, so I could wet it andbreak seals to make changes, but after 6 months I sealed everything in silicone. Whatever you do,don’t use any metal parts, or the hydrogen sulfide in biogas will corrode the parts.
Dear Shaunthanks a lot for your informations.I am a MSc Student working on Biogasyour weblog helps me a loti will try to open a business based on biogas here in my countrythanks agin
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13. smitha on January 18, 2013 at 1:27 pm said:
Hi Shaun,
We are conducting a project on biogas production preferably using a combination of cow dung andpartially decomposed vegetable waste, and water in the ration of 1:1 in conical flask of 500 ml fitted withballoon. initially after 24 hours we found the balloons were inflated, but after 48 hours the balloon shrunkand after 72 hours there was inflation, and after 6 days the balloon was totally pulled (sucked)into theflask. can you please tell us why there was reduction in gas quantity on the 2nd day and total suction onthe 6th day.smitha
Reply ↓
Shaun on January 19, 2013 at 2:22 pm said:
Thank you Smitha, that is a fascinating experiment. Sorry for the delay, and I hope by now youhave a balloon full of biogas!
Once a digester is filled and fed, it can take up to three weeks before biogas is created. This isbecause different bacteria have to take turns digesting the feedstock, and methanogens (whichcreate biogas) are third in line.
First, yeasts consume the sugars in the feedstock, producing alcohol and carbon dioxide. This wasprobably the cause of the initial balloon inflation. This is the way beers and wines are brewed.
Second, acetogens consume alcohols (and oxygen) and produce acids. This may explain thesucking in of the balloon. This is the way vinegar is made.
Finally, methanogens are able to consume acids and produce methane gas, which is the flammablecomponent of biogas.
So you can see, methanogens have to wait their turn. Also, once methanogens are working,acetogens and yeasts are still working, which is why biogas is made up of methane and carbondioxide.
I hope this helps. It would be interesting to see if adding a bit of vinegar to the mix would allowmethanogens to start earlier. Let me know how your experiment goes.
Good thing
Reply ↓
14. duncan on January 30, 2013 at 8:58 pm said:
Hi sir,Can one use a normal gas cooker with biogas? If so does one need a gas regurator?
Reply ↓
Shaun on January 30, 2013 at 9:12 pm said:
Hi Duncan,
Yes, you can use a normal gas cooker, but you will have to remove the gas restrictor, which canusually be unscrewed. Make sure you can adjust the air intake, because biogas burns best when itsmixed with air. Good luck!
Reply ↓
15. duncan on February 4, 2013 at 10:50 pm said:
Hi Shaun,Thanks alot for your support.I just read in your article that this gas reacts with metal, wont it damage mygas cooker’s metal piping? The other question is why is your feed pipe funnel lidded?
Reply ↓
Shaun on February 10, 2013 at 12:43 pm said:
Good thinking Duncan! Yes indeed the hydrogen sulphide in biogas will corrode many metalsincluding brass, which is likely what your gas intake is made of. However, H2S is not corrosive toaluminium, so try protecting your metal with al-foil. Also, I don’t know how rapidly your cookerwill corrode – it might not be an issue. You could experiment by putting some metal in yourcollector.
For your second question, there is no need to have a lid on the feed pipe. If I forget to open thegas-out valve on the digester, biogas builds up and starts pushing effluent up both pipes. I did thisonce and at some time during the night the lid blew off and sank to the bottom of the collector!Also, effluent had been overflowing out the input pipe which made an ugly scene requiring acomplete hose-down. I keep the lid on for tidiness and so as to not encourage flies. The lid on theoutput pipe is more useful, because it prevents any drips. With both lids in place, there can be noodours from the system, and the whole thing can be hosed down.
Reply ↓
duncan on February 12, 2013 at 6:28 pm said:
Thank you very much for the support. I am doing an experiment with 3 20litre cans based onyour design. It is now 10 days old and hasnt seen any effect on the gas collector. Am tryingto be patient.
Reply ↓
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Tweet Subtitles: Turn off the gas-out valve Fit the effluent bucket securely Remove lids from theinput and output pipes Rinse-water, including coffee grinds and expired Read More »
002: Integration
2:04 am By ShaunTweet Integration In a permaculture system, any one element serves as many intended functions aspossible, and as I touched on earlier, introduced elements often end up Read More »
001: From Sand to Sustainability
9:31 pm By ShaunTweetA Brief History It’s been two years since I began work on the backyard, and it’s been achaotic process of trial and error and learning. Read More »
What is Permaculture?
2:44 am By ShaunTweetWhat do I think it is? Permaculture is a vector through which people can learn and applythemselves to affect change in a landscape toward a Read More »
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