Flexi-bag Biogas digester is full – Anafura kama mandazi!

Hi folks, it’s only been a week and my biogas digester looks – well positively like a mandazi (a donut like delicious breakfast bread – it’s 6 am and I’m hungry!).

I’m so chuffed with my biogas. Check it out

After 1 week it's looking dangerous - just hoping it wont explode while I'm away

Here it is on day 1.

We are on our way to northern Kenya and had to leave on Tuesday for the 2 day drive – before I left I went to check on my experiment which had gone disgusting, so I chucked it out.  Long story short – cow dung produces the most biogas, kitchen waste simply got fungus and consumed all the gas and sucked the condom into the cup – wondering what the hell I’m on about? Check out the experiment here.

Does kitchen waste produce as much biogas as fresh cow dung?

I am hoping to have a very successful home biogas production system (which I wrote about here)  in about 2 weeks. But what should I feed into my system to make it really successful?

According to Dr. Anand Karve  on the ARTI website 2 kg of carbohydrate rich vegetable feedstock produces about 500 g of methane, and the reaction is completed with 24 hours. While the conventional biogas systems, using cattle dung, uses about 40 kg feedstock to produce the same quantity of methane, and requires about 40 days to complete the reaction. He won an award for this finding.

So should I switch from cow dung to kitchen wastes?  I’m not convinced – maybe Dr. Karve’s Indian cows are less flatulent and produce little biogas – I know that our Kenyan cows are super producers of gas.  But then how can I be sure?

A shitty experiment

To find out whether kitchen waste is better than cow dung, I am conducting an experiment that involved cow dung, plastic cups, condoms, water and kitchen wastes.

I added equal amounts of dung and water and mixed it and poured into a plastic cup, then covered it with a condom to enable me to see the gas forming.

The same amount of kitchen waste was similarly mixed with equal amounts of water and mixed poured into a cup and covered with a condom.

A third experiment involved a mix of dung and mashed kitchen waste, mixed with equal amounts of water, poured into a plastic cup  and covered with a condom. I conducted this experiment in my kitchen using clean disposable utensils and unused condoms (had to say that just in case you people think I’m really weird).

Results

I’ll be posting the results in pictures here

Day 0 (May 25 9 pm)

The condoms are all empty and flaccid. Sad. There was a slight emergency when one of the condoms broke as I was putting it on the cup…  I had to get more condoms purchased at 9 pm. Pharmacist was amused.

Day 2 (May 27th 9 am)

Hmmm, some biogas already being produced and poop looks like it’s slightly more than poop and veg which is more than veg alone. So far I’m putting my money on cow poop.

Day 3 May 28 10.20 pm

Watch this space for coming days and potential explosion of cow poop in my kitchen.