pooh-power!

[martin]

- large slurry lagoons, the thought occurs that this has got to be a potential source of methane, which could be used in all sorts of fun ways. My knowlege of such things date from the 70's, there's the famous "Good life" device in the cellar, and John Seymour included full diagrams in his excellent "Self Sufficiency" manual from around 1973.
Presumably, things have moved on since then - anyone got any idea of how you could implement such a scheme? - and am I correct in supposing that once it has been anaerobically digested, could the result be dried and bagged as fertiliser?

[AndySV1K]

personally i think the idea stinks

 

Andy.

[Amaterasu]

having stood up to my chest in these a good few times in a previous occupation (rescuing stupid cows that seem to think that the lagoons are swimming pools) i can vouch for the fact that they are very smelly and surprisingly warm, in a custardy sort of way.

One problem I can see is that my current neighbours would not take kindly to me dumping large quantities of cow poo in my garden pond 

[Ivan]

However, it is not that dis-similar in design to a commonal garden septic tank or cesspit - simple modification required?

[furkin]

They use a very similar method in some Third World Countries (& some not so 3rd world ??).
I have seen them scoop 'the material' from just a couple of cows, & use the methane to power a one ring burner (Johnny Cash ??).  They were using their hands to push the slurry through a sort of drain in the floor – I assume that they had an underground tank of some sort.
Without this, they would have to revert to open fires.

[Crofter]

you should have a read of " a chinese biogs manual" ISBN 0-903031-65-5 more info about poo than anyone really should know 

[jack]

In a passing comment from one off our friends-"why don,t you save the gases from your septic tank?"

So in true fashion -where do I start looking for info. -Already have a 1kw wind generator up and running.

[Ivan]

There was a great demonstration biogas plant mounted onto a trailer at the Renewable Energy event at Gelli Aur on Wednesday this week. Unfortunately, I forgot the camera, so I did not get the chance to take any photos. During the day, the plant filled numerous tractor tyre inner tubes, which were burnt off during the day to demonstrate the heat available.

[odbob]

One or two water authorities already have systems of methane collection, in the distant past I was involved with this, we ran, quite successfully, small combined heat and power units off this methane. One major problem though was that of filtration of the collected gas

[Alan]

Hi Od Bob

Just burning the gas very local to the Bio digester is very straight forward.

You do need large volume water traps and a fall in all pipe work to use the
gas in a internal combustion engine. Even with stainless steel control valves
and regulators corrosion of valve seats is a problem

Regards

Alan

[Peter.N.]

I think this subject has been researched before and the conclusion was that a domestic septic tank will not supply a viable ammount of methane - unless you run a hotel of course! But a livestock farm does, unfortunatly there are not to many of those about now, the one where we live only seems to be farming horses. Sewage plants and also landfill sites though, can produce useful ammounts of gas.

Peter.N.