Home: Kitchen: Garbage Disposal
BioBox: elegant power from kitchenwaste   (+6, -1)  [vote for, against]
Grind beans and pour water on them, ferment and plug in your iPOD

The BioBox is a micro-biogas-digester for (sub)urban households and for people who want to recharge the batteries of their gadgets with bio-energy!!!

Please see the picture (where it says: fantastic picture), to get a shortcut.

1. An average household in the UK produces some 4 kilogram of food and kitchen waste per week

2. from this, you can in theory, using a set of off-the-shelf components, draw 12,000 watt hours of energy per year, if you convert the waste into biogas and then into electricity

3. this biobox is for (us) wealthy suburban people in the 'highly developed world', it is an object like a micro-wave oven; but the inspiration comes from micro-digesters as used in many developing countries

4. it is about the size of an old table-top computer (bit larger), and deserves a nice design

Ok, so you drop in your kitchenwaste, which follows the following parcours:

-it gets shredded and mixed with water

-this sludge falls into a simple digester that is mildly heated (see below)

-the biogas thus produced is burned in a simple bunsen-burner type device

-this flame heats an external combustion engine (stirling), which powers a generator

-the electricity thus produced is stored in a battery

-plug in your cell phone, iPOD, epilady or any gadget, and charge the battery

Simple. Elegant. Maybe efficient.

-you recuperate some of the heat of the stirling, to heat the digester >> you use the water tank as a cooling medium to cool the stirling's top-side; this slightly heated water is perfect for the digester's temperature needs

-12,000 watt hours per year equals around 3333 fully charged iPOD batteries, or 6666 fully charged cell phone batteries!!

Note on a current event that influenced this little idea: a community here in Belgium has stopped collecting organic waste (which households had to put in the green box), for the simple reason that the council calculated that it took too much energy to collect this waste, separate it further, and digest it to produce biogas. The community explained this to the people, who were adviced to use the organic waste to make their own compost. For those who don't want to bother, they can now throw their kitchen waste in the ordinary bag.

Mind you, Flanders is world record-holder when it comes to smart waste management. But after decades of experience with many different systems, some communties have come to notice that the energy balance doesn't work out.

Of course, this all depends a bit on the location and the circumstances. But still, this came as quite a shocker to (us) the greenies.

I made a fantastic picture of the BioBox that charges gadgets.
-- django, Jan 21 2007

BioBox: fantastic picture http://i3.photobuck...esel/bioboxexpo.jpg
It looks like a winner!!!! [django, Jan 21 2007]

Biogas powered epilady http://i3.photobuck...esel/epiladybio.jpg
For the environmentally conscious woman. Note: machine not to scale. I'm sure it will work!! [django, Jan 22 2007]

Anaerobic digester calculator. http://biorealis.co...gester_revised.html
Using estimates from my household, minus poop, I got 21 cents worth of biogas each day. [bungston, Jan 23 2007]

Gasometer http://en.wikipedia.org/wiki/Gasometer
[BunsenHoneydew, Jan 23 2007]

Blender http://blender.org/cms/Home.2.0.html
Light, easy to use, free [django, Jan 24 2007]

What computer program did you use to create that fantastic picture.
-- BJS, Jan 21 2007


I'll tell you if you join me for a croissant. Coffee's on me. :-)
-- django, Jan 22 2007


The shredder should be hand-powered. Include a crank in you very much fantastic picture so people don't come up with stupid comments like this.
Digested sludge is plumbed to waste water line, yes?

psst. shethinksnot informs me the epilady is mains-powered.
Have a shredded, semi-digested, warm croissant [django].
-- methinksnot, Jan 22 2007


Yah! Another way for wankers to explode their kitchens at 3:00am!
-- Galbinus_Caeli, Jan 22 2007


I like it.

Now it just needs a fantastic picture of the ventilation system.
-- 2 fries shy of a happy meal, Jan 22 2007


You should outfit one onto a fantastic looking DeLorean.
-- daseva, Jan 22 2007


Yes, yes!! Good ideas: hand crank, connection to waste water, and ventilator for CO2 removal.

I also just read that the average number of pets of the average UK household produce around 1 kilogram per week of highly biodegradable dirty things. This is most welcome!

PS: youthinksnot, we will invent a biogas powered epilady so we have a solution to the problem.
-- django, Jan 22 2007


It seems to me you could probably poop into it too.
-- bungston, Jan 22 2007


Hooray! Something else for Triumph, the Insult Comic Dog!

Drawn in Google Sketch? At any rate, it looks a wee bit like an xbox.

Anyway, your math is a bit off in the top righthand side.

4kg * 16% is actually .64 kg, not .16 kg. This may increase your output.
-- shapu, Jan 22 2007


I have been thinking about biogas recently. It would seem prudent to have a starter culture of good biogas producers. You can't rely on your chinese leftovers having the right bacteria in there.

I think it needs to be bigger. I wonder if this device could be rigged up to serve as a septic tank as well - or a septic tank retrofitted to produce biogas? A septic tank is big, it is outside, and you harness all the power of your poop as well. Plus by calling it a septic tank you might be able to sidestep zoning issues. You could chuck dog poop / grass clippings in as well.

I like those leg hairs. No footsie under the table for the cactus queen!

[django] - are household biogas digesters actually used anywhere? It seems like you could cook over these flames as well, although if there was a lot of hydrogen sulfide that would not be too good.
-- bungston, Jan 23 2007


Okay django, I gave you a croissant.
-- BJS, Jan 23 2007


//I have been thinking about biogas recently//
It's always about gas with you, isn't it?

Biogas-powered epilady: Only suitable for mothers-in-law.
-- methinksnot, Jan 23 2007


//are household biogas digesters actually used anywhere?//

China, although they tend more to be several families and all the pigs and chickens scale, rather than single Western sized house (+/- poop) scale. I understand larger ones are reasonably common in rural Australia and the US, especially at feedlots and chicken batteries /no pun intended/
-- BunsenHoneydew, Jan 23 2007


Oh, and lose the battery. Make the digestion tank a gasometer [link], and have the generator run on demand.
-- BunsenHoneydew, Jan 23 2007


Hi BJS, I use Blender. Open source and pretty straight forward software. See link.
-- django, Jan 24 2007


I have been thinking about bioreactors. I wonder if they can be bought off-the-shelf? It seems like every zoo should have one.
-- bungston, Mar 02 2007



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