Our Biogas Kitchen

In Germany it was our common practice to compost all of our kitchen waste. Now that we have built an ARTI India style biogas digestor on the porch, however, we only compost the tissue paper, napkins, cardboard, tea-bags and fibrous, cellulosic material that our household generates as garbage. All the food waste (including flower petals and banana peels) go into the blender with warm water and then into the biogas digestor. What we get out is liquid fertilizer for our rooftop herb, berry and vegetable garden, and biogas. We are still experimenting with the yields of gas, but are so far averaging 10 minutes a day for the small size of our digestor and the small quantities of food waste our family of 2 (with a baby) generates. Two days worth of kitchen waste gives us enough gas to usefully cook for 20 or 30 minutes.

Category:

Science & Technology

Tags:

• kitchen
• garbage
• biogas
• digestor
• ARTI
• India
• style

[MrAnthonyRizzo]

Also I would like to know:

3) The water extracts the nutrients from the bacterial digestion to make compost tea, which you use in your garden.

a. What happens to the solid biomass left over after extracting the bio gas and the compost tea?

b. How do you extract it from the digester?

Thankyou for your time and answering my questions. Your videos are very informative.

[tculhane]

@MrAnthonyRizzo The compost tea made from the biodigestor is indeed active and very rich in micronutrients. Because we don't put much fecal material in and no lignocellulose (straw, leaves or grass) we haven't had any appreciable build up of solid biomass over the past nearly three years. Maybe in another few years we will have to vacuum out some solids but I doubt it. If we do, they will make a nice addition to the compost. To extract them we would just stick a wet vac hose down.

[MrAnthonyRizzo]

Could you answer these questions for me please?

1) How long can you keep producing bio gas from a fixed supply of liquefied food waste, for example let’s say 50 gallons?

2) Is this system any different than the one that extracts methane from cow manure or human manure?

a. If not can the two systems be combined to effectively convert not just the kitchen scraps but also bathroom fecal matter into bio gas and possibly compost tea and compost?

b. If so, what would the process entail?

[tculhane]

@MrAnthonyRizzo Thanks for your interest! Quite a bit has changed in the two years since we made that little home video; we no longer use the blender, now we put everything through our Insinkerator food disposal which is automatically pumped to the digestor on the porch. The digestor can also use fecal material and we put our baby's diaper wastes into it but haven't gotten around to replumbing the toilet. It is the same as any digestor that uses cow manure except that food waste is richer.

[slicerr2]

hi i was wondering if you could send me plans on how to build the biogas plant i need to make one for science fair

[tculhane]

Slicerrr2, just put a smaller bucket upside down into a larger bucket. Make a 1/2 inch hole in the bottom of the smaller bucket which you can fit a tube into airtight (acquarium shops have the tank fitting). Make a 2 inch hole in the bottom of the larger bucket and put a fitting in that and run a feeding tube into the center of the larger bucket. Fill with water and horse or cow manure the first day and let ferment for two weeks. Once you start getting methane, feed ground up food waste.

[MrAnthonyRizzo]

@tculhane I didn’t pay attention to the date on the video. You are right. Quite a bit of time has passed. It sounds like you have refined the process and that it is working well for you. I’m still curious though; do you know how long you can continue to produce gas on a certain quantity of biogas? It seems that if you keep feeding it that it will keep producing but I’m just wondering how much gas can a a certain amount of waste produce. Thanks again for your responses.

[MrAnthonyRizzo]

@tculhane Barely any sediment buildup after three years, really? All I can say is WOW! I did not know that turning kitchen scraps into bio gas was so efficient. You really do have a great setup there. It is wonderful to see that rather than producing waste you are producing fuel and liquid amendments for your garden. It is not only economically expedient but it converts a very harmful greenhouse gas into something less harmful.

[UmyNEPHEW]

your blender is quiet!

[derrickandnaoko]

how cold does it get there and does your system work all year? Love your video by the way!!

[stevevidzi]

I have been promoting biogas use for some time, and I particularly liked this video which I think is the best I've seen at showing how simple and practical a home biogas digester system can be.

[Crestonians]

Hi there, not sure if you still check this. Can you use a regular household natural gas stove? If not where can you find a biogas stove? Thanks