Hydrofracture: State Of The Art In South Africa
During the past five years, the Department of Water Affairs and Forestry of South Africa have hydrofractured a large number of low yielding boreholes in different geological and geohydrological regimes. In the Swartwater study area (10 holes), the results indicate that boreholes that were scientifically sited in order to intersect geological features such as faults or contacts are the most likely to be sucessfully stimulated. In the case of random site selection, the sucess rate was extremely low.
By using the newly developed hydrofracture unit and carefully selecting the holes to be stimulated, a low-yielding water borehole can be sucessfully converted into a production hole for between 35 and 45% of the cost of drilling another borehole.
La mise en oeuvre d'une unité de fracturation hydraulique nouvellement conçue et le choix convenable des puits à développer améliorent considérablement le rendement des forages pour un coût équivalent à 35 à 45% de celui d'un nouveau forage.