Design and construction of mini biogas digester for family use

The biogas digester is composed of a green house made with hollow sunlight sheet and metal supporting frame, a membrane digester with a gas storage bag combined in one, a stainless steel sink, a stainless steel outlet, a biogas filter and a biogas booster pump:

1. Biogas production of 2m3/day is good enough for a family

2. It is a DIY kit small scale biogas system for convenient transport and easy assembly.

3. It is surface mounted, there is no need for digging or heavy construction.

4. It can be assembled within 2 hours by anyone with manual and video guidance.

5. Treated organic waste locally, use biogas for cooking, electricity or feed garden with nutritious liquid fertilizer.

6. Used for family, farm, restaurant, hotel, resort to treat organic waste, such as food waste, sewage sludge, animal waste.

7. Light weight and easy to install, packed in carton box.

8. Life span more than 10 years - made of stainless steel frame

9. Raw material of green house and PVC biogas storage bag

10. Specification 156*120*195cm

11. Methane Content 65% which is excellent for cooking
 
 
Construction video:
 
 
 
 More info:

DIY kit assemble mini biogas digester for family use


Calculation of feeding ratio for 1000 liter biogas digester

To my understanding 1000 liter/40 = 25 liter. So it is advisable to feed 25 liter of food waste mixed with water. It means, your food waste is already included in that 25 liter. I have read from this elsewhere, the maximum ratio of food waste to water you can apply is 1:1 (though to me its too much for the microbes to handle). Roughly the maximum weight of food waste you can put is 12.5 kg in which you add another half of water to add up to 25 liter as total mixed. However its up to you what level of total solids you want to practice by reducing the food waste within that 25 liter. The more effluent you take out from the digester, the more bacteria you will discard and that may affect whole digestion process and becoming slower in producing gas.