Kivu lakeMethane
Gas Extraction
Putting methane
to work
Natural hazards


The column will be assembled on the ground. As it is lengthened it will be pulled into the lake. Once all the pieces are assembled the column will be towed out into the lake by boat and fixed to the barge, which has previously been anchored.
The following diagrams show the different phases of the immersion of the column using ballast linked in series to a compressor.



First phase in the immersion of the column.

The ballast for the column begins to fill with water. The filling process for the ballast is slow and reversible if there is a problem during the immersion of the column.


Intermediate phase in the immersion of the column.

The ballast containers are filled one after the other so that the speed of descent of the column is controlled.


Final deployment of the column.

All the ballast containers are full and the ballast of the column keeps this latter vertical. The dimensions of the column ballast depend on the force of expulsion developed by the auto-siphon. Experimental models having determined this force, the ballast will be larger than strictly necessary so as to avoid any pointless risk.

It was decided to leave the column with a certain degree of free play by not making the ballast containers rest on the lake bottom. In fact, although the column is ballasted it can follow the movements of the barge caused, for example, by currents. This degree of freedom seems to us to be indispensible given the fact that pressures caused by wind and swell on the lake can be significant.