Propane Generator Grid Tie

[Dr_Doggy]

maybe, post 39 math was done on the fly using those google found charts, but when you think, 240lbs dung is 10% cows body weight, sounds about rite, then other chart shows how much methane you get from said 240lbs dung

here is another chart that confirms fart levels, if we decided to bag them!:
https://news.bbc.co.uk/2/hi/uk_news/magazine/8329612.stm


but again these numbers are nothing, since really getting natural gas from the pipe is just soo cheap


edit: cant find flaw in math if chart is correct

 

[tcmtech]

The chart is way way wrong in a number of areas.

Just ask the guys who know cattle for the real numbers. For one a typical beef cow weighs about 1200 pounds not 2400 and eats around 25 - 30 pounds of food a day.

https://beef.unl.edu/cattleproduction/forageconsumed-day

https://www1.agric.gov.ab.ca/$Department/deptdocs.nsf/All/faq7811

Personally I have been around cattle and have seen how much they poop in a day and one cow in a barn with all the feed they can eat does onto make anywhere near 10% of their body weight in manure.

Dairy cows however do drink a huge amount of water though. Something like 20 - 25 gallons in a day is normal.

As a rule of thumb, consumption will range from 1 gallon per 100 poundsof body weight during cold weather to nearly 2 gallons per 100 pounds of body during the hottest weather. Lactating cows require nearly twice as much water compared to dry cows.

So either way you can't make 240 pounds of poop and 24,000 liters of gas from 25 pounds of grass and 150 pounds of water.

 

[Dr_Doggy]

yes i trust, just a city dog here, that would throw me off by a factor of 8, so actually we would need 120 cows
however i have not yet looked deep in to liquid wastes, but a quick search does mention urine enriching the system as well

hmm, that would bring an additional problem too, the digester needs to hold about 60x volume processed per day

 

[large_ghostman]

I am working on Bio methane at the moment, I asked in another thread about cell density. I am using professional equipment for the gas reactors and have read a great deal of scientific papers.
The gas output varies on type of cow and diet, for example large Holstein cattle can produce upto 419 ltr a day of methane. These are dairy cows and produce below the capacity of beef cattle, I will try and attach a paper where this figure comes from. Now because I know certain people argue black is white even when you cite things (not you guys BTW) I can tell you that I dont cherry pick papers I use those that fall between high and low or come from a non arguable reputable source. Bio Gas has been a huge project for me, it was something my dad had worked on for over 7 years before his brain got spongy.
I am trying to build a super cow's stomach! Most methane reactors are only 60% efficient at best, there are many factors to take into account with methane production in a cow, its way more complex than energy in versus energy out.
A cows stomach contains billions or organisms that also decompose themselves and produce gases, a cow eats organisms with the grass also (a baby cow when it first eats solids, eats grass around its mothers cow pat! this seeds its stomach with the eggs of the methogenes ). If you want hard data shout me I have alot of papers on this you are welcome too.
it wont seem to let me post the pdf paper with the information I used!! I will have to post a link to it instead, sorry about that

https://scholars.unh.edu/cgi/viewcontent.cgi?article=1289&context=nhaes

 

[large_ghostman]

Keep in mind I wont be sharing my method yet!! I fully intend to finish my dads work and sell this, but I am happy to help with more conventional systems and how to make them perform better.
Cow poo is not the best feedstock for a bio reactor, its a great starter culture but you need to find high N and C feedstock and balance them 4-1 in the first reactor and 2-1 in the second stage. I use a 4 stage system very much like a cows stomach, but for normal gas production a single reactor unit will produce around 34% of available Methane, a 2 stage system will produce upto 47% available methane but can be tweaked with effort upto around ~60%

 

[large_ghostman]

Beef cattle can produce around 440-760 ltr methane a day. You will have trouble calculating methane output from manure as the factors involved change, also most methane plants dont use just manure. The best ones use a mixture of organics and have a layer of both willow sawdust and willow chipping, willow is the best but any can be used.
the idea for the sawdust and using green willow of a young age thats shredded is for the lignin and liganase, this slowly breaks down the fibers and produces a controlled source of carbon and nitrogen (amongst other things), it also plays a roles in offering a stratification zone for true anaerobes rather than the obliques that are required in other 'zones'.
While a single chamber unit can be used its pretty poor compared to even a two chamber system, there should be different temperatures and PH values for each chamber. If you want to make Bio gas then with some effort you can get a pretty good rate from 2 chamber systems, we have an adapted septic tank for Methane but its not great at the moment and needs an upgrade. We scrub the Bio gas and clean it up so we have methane, scrubbing the gas is pretty easy.

One surprise I found was looking at how cattle expel methane, while there isnt much I could find for cattle I did find a study for sheep. Everyone assumes that most methane is lost via farts, but at least in sheep they actually expel more through the mouth and nose!! I have the paper in DJUE format and again cant attach but the reference for this is

Murray, R. M., Bryant, A. M. and Leng, R. A. 1976.Rates of methane production in the rumen and large intestine of sheep. Br. J. Nutr. 36: 1–14

While sheep and cattle are different they are both Rumens so I guess its wise to take into account other routes of emission. I notice you have tried to work figures based on weight and diet intake, this wont give you an accurate figure, Methnoegens are more complex than that. its isnt solely a case of using part of the food intake and converting to methane, as you mentioned saliva it is also a key player in production with many organisms breaking down both the saliva and the bacteria that live in it to form different bio gases.

There are some good general studies on bio methane plants but you have to be careful, some cite figures that can be nulled to some extent, for example alot of papers take into consideration the electric cost of heating a bio reactor, but with good insulation and using the hot exhaust gas alot of this can be excluded from calculation, alot of research has been done in India on Bio gas plants and the current world leader believe it or not is Hungry!! They seem to be streets ahead with the technology but are alot more secretive about the process.
The newest German plants are multi pass systems but I dont have upto data for them yet

 

[Dr_Doggy]

I seen the pics, was wondering what that was!, I just say farts cos it s funner and associates to an image i posted somewhere else, it is actually quite amazing that any organic breaks down as such. Also thanks for clearing up, was wondering about stages. Also I think the problem with figures is that it may just be a promo out here, may deflate with popularity, and prolly arnt the same in other places.

It is also very interesting on the profit you get on a biofuel system, without any biofuel at all, unfortunately even going on a ledge i can only rake up 10% of the cost of the old system.
I found a way to cut out the middle men and most of the expense however i doubt it is strictly legal, so i wont bother to elaborate or design.
But I hope you guys are able to squeeze a buck out of this.

It seems this is popular topic specifically with the revolutions coming, I have seen links as well where they are trying to use it for septic systems.
Check out the "Bloom Box" or microbial fuel cell, apparently google dropped like 50million in to some of these.

I actually got in to this when i wanted to see the bio value of compost materials , there is alot of food wasted at my place and it makes me very sad. But since im so small scale a little cell to power a small light bulb may be the way i should go(an just forget the grid). It will be interesting to see in 10 years if we all actually have home power plants sitting next to the A/C unit.

 

[large_ghostman]

I seen the pics, was wondering what that was!, I just say farts cos it s funner and associates to an image i posted somewhere else, it is actually quite amazing that any organic breaks down as such. Also thanks for clearing up, was wondering about stages. Also I think the problem with figures is that it may just be a promo out here, may deflate with popularity, and prolly arnt the same in other places.

It is also very interesting on the profit you get on a biofuel system, without any biofuel at all, unfortunately even going on a ledge i can only rake up 10% of the cost of the old system.
I found a way to cut out the middle men and most of the expense however i doubt it is strictly legal, so i wont bother to elaborate or design.
But I hope you guys are able to squeeze a buck out of this.

It seems this is popular topic specifically with the revolutions coming, I have seen links as well where they are trying to use it for septic systems.
Check out the "Bloom Box" or microbial fuel cell, apparently google dropped like 50million in to some of these.

I actually got in to this when i wanted to see the bio value of compost materials , there is alot of food wasted at my place and it makes me very sad. But since im so small scale a little cell to power a small light bulb may be the way i should go(an just forget the grid). It will be interesting to see in 10 years if we all actually have home power plants sitting next to the A/C unit.

To make it pay you need to go and talk to water companies , get the fatbergs and use that. Some (in the uk) will give you money to look into it, they spend a fortune clearing fat waste from sewers and it makes a great bio fuel for cars or can be broken down in a digester (areal pain and better to break down into fuel first).
I have had a small petrol generator running from the gas on the septic tank, but I had problems with the feed in.
Methane plants are getting popular here in Scotland at the moment, especially the combined heat and energy ones. I would keep at it, ignore the rubbish on american bio fuel sites regarding titration numbers and not bothering with solid fats, The money is in the solid fat waste not waste veg oil. Everybody and his dog is after good waste veg oil and the price has jumped. NO ONE wants the solid fats but they can be made into biofuel easy enough if you do the research, alot of places will actually pay to give you this stuff, Look into non chemical and chemical means to extract the fuel. Many times sulphuric acid is used as a drying agent in some parts of the process, this is expensive and not needed. I would use saturated salt solution for any dehydration before the final wash stages.
After that I would go the clacium sulphate/magnesium sulphate route then use an acid if I had too.
To get a good idea how wet your fuel is you dont have to mess about doing this test or that test, simples to use copper sulphate (root killer over there) and heat it gently on a tray until a very very pale blue, this is the dehydrated form,the normal form is a deep blue.
Put a small amount of the copper sulphate powder into the fuel and see if it clumps and goes blue, if so you have alot of water. When the fuel is dry you wont get clumping or much of a colour change, you can dry fuel with copper sulphate then filter and dry the sulphate again, but I would use the other drying agents instead and keep the copper sulphate for a quick water test.
Also keep the glycerine and distill using the heat from the exhaust manifold, distilled glycerine has a pretty good value or can be chucked in the bio digester without bothering to distill.
If its organic (including carbon particles) sling it in the digester. I couldnt get ammonia before we had a company registered here so I used maggots to produce the ammonia and then distilled the liquid (mostly ammonia anyway) .

 

[Dr_Doggy]

I was surprised that these devices could support a whole range of inputs, but i like that!:
**broken link removed**
even grass clippings! Im sure there is abundance of that in my area!

Also I am curious as to the problem you had with the petrol generator, I have heard that the main thing was too much CO2 in the line. Havn't looked into the details about drying yet, but i wonder if a car radiator in a tank of water would work. (passing the gas through the inside pipeline where coolant would go)

 

[large_ghostman]

No mine was a physical problem getting the gas flow correct, I dry the gas first by reacting the CO2 through sodium hydroxide and then use a desiccant inside a gas wash bottle. Yes biodigester will eat all organics. I will get some material together for you at the weekend and share some of my experiment results for the old digester.

 

[JimB]

This thread has become a spam magnet, so I am locking it.
JimB