Construction of a biodigester
In the previous post (I) I explained the strenghts of a biodigester for a small kitchen. In this post I will try to summarize the steps to construct one, from Jaime Marti PDF, “Biodigestores familiares.”
1 .- Double layer plastic
Cut the black tubular polyethylene rolls of desired size, leaving 50 cm extra on both ends (input and output). Extend completely the plastic sleeve above the ground. One person holds the end and, without releasing it, crosses inside the digester, so that there is only one double-layer sleeve, since it is a tubular roll, seamless.
2 .- Biogas output from biodigester
In the upper half of the biodigester make a small cut on the two layers of plastic and put a bulkhead (flange) as shown in the photos. Take good care of the complete sealed to prevent outside air from the biodigester.
3 .- Inlet and outlet sludge pipes
Once the biogas output is ready, it is time to close the ends of the plastic sleeve tied to the inlet and outlet pipes. Make accordion folds and tied tightly with pneumatic league.
4 .- Introduction into the ditch
Place the plastic biodigester in the trench previously prepared, very careful to not cause any hole and reviewing not have wrinkles.
You have to calculate the mixture of manure and water has to clog the air intake and also their escape. The biogas generated has to exit strictly through the upper pipe. The sludge has to overflow through the outlet pipe.
The digester has already prepared the output of the biogas. Couple an outer pipe 1 / 2 “PVC to the kitchen, which should be about 20 to 50 meters maximum away.
7 .- Water accumulation inside pipes
The pipe will be high, never buried, to facilitate water drain condensation that may occur. In the “valleys” of the pipe place a “T” plug for periodically purge.
The safety valve near the digester has two functions: Allow the escape of excess of not consumed biogas as well as Prevent air inlet from outside (which would kill the internal process of generation of biogas). A plastic bottle with water is sufficient.
9 .- Gas reservoir
The reservoir will be the biogas storage tank that feeds the kitchen and regulates the pressure of the gas. It must be hung near the kitchen, accessible, preferably outside but under cover of sun, rain and wind. It is built with the same procedure of the biodigester.
10 .- Biogas kitchen
The reservoir will have a pipe with stopcocks highly visible and directly to the burners, that can be housed with mud and adobe. That’s all!
What’s your positive or negative experience? Your comments are very welcome!!
You can find detailed explanations in the original document (in Spanish) BIODIGESTORES FAMILIARES. Jaime Martí.
- Biogas Kitchen. How to calculate your Biodigester (and III) (albertcampi.me)
- Biogas Kitchens. Low Cost Biodigesters (I) (albertcampi.me)
- Biogas and Biomethane Gains Wider Acceptance (bioenergyconsult.wordpress.com)