DANTAN has together with engineer Jan Mallan and Superflex been working with a biogas concept for about 10 years. It started from an interest in developing a biogas system that would fulfill the demands of an average African family for cooking and light.
We wanted to focus on the family as the target group and set out to develop a new type of system that would not require highly skilled labour to install.
The DANTAN Supergas system is a two-chamber system with a hydraulic valve. It consists of an inlet, two water tanks, connecting underground pipes, outlet, hydraulic valve, a gasometer, condensation collector and connecting gas pipes. The system has no moving mechanical parts. It uses only a minimum of water and sludge can be unloaded from the digester while the system is in use. The hydraulic valve secures automatic stirring. The stirring mixes old and new organic material and hereby increasing the gas production.
The first test of this new system was done in collaboration with the NGO, SURUDE in Tanzania. This system was made of a soft PVC membrane. The system was functioning for several years, but we learned that the soft PVC was working, but it was also fragile. We decided to make an improved system, which we tested in Cambodia still based on the soft PVC membrane. We were still facing problems related to the fact, that the material was very fragile.
After this, a test was carried out in Thailand where we made the systems from already existing watertanks (PE) that we procured locally. These tank proved to be much more durable and easy to work with. Every installation was made from what was available locally with the help from a local constructor.
Right now we are working in Zanzibar together with a local NGO, ZALWEDA,- to copy and modify what we did in Thailand to fit the local context and conditions. It is a 5 years project that involves installation of several systems, know-how transfer and micro credit systems. The idea in Zanzibar is to set up a pilot system together with local constructors and then after 6 month additional 6 systems should be setup by the local constructors supervised by us. And then after this they should be able of installing systems themselves.
In an early stage of working with biogas we aimed for a commercialization of small-scale biogas systems in order to make then more product oriented. In this process we tried 10 years ago to get investors to invest in the development of the system but this proved to be difficult at that time. Today we still think that the right thing to do would be to commercialize the system, make it easier to install and finally to get distribution. This commercialization have to match the economic ability of the end user and it is also very important for us to make this technology available through an open source hardware strategy. In principles this could mean that we develop a product but at the same time we encourage others to develop and copy the system for a mutual benefit.
The 2 pilot plants have been working for 6 month now and are closely monitored. After the planned micro credit training the next 6 plants will be installed.
At the current stage the system has proved to work efficiently, but we are still seeking persons, companies or organizations that would be interested in developing it further. This is mainly about making a design that decrease the production cost, make the installations process easier and to aim at a local production possibility (it could be produced on the factories that produces PE water tanks). We have already designed an improved system based upon our experiences from Zanzibar that should be easier to produce and install.
October 2008, jesper kirknæs
www.supergas.info