Published January 2011
About the effectiveness of isolation method of water influxes to the wells
Y.M.AlievThe analysis of the existing methods on isolation of the water in the wells producing the heterogeneous porous formations has been carried out. It is shown that well sludging mainly takes place in the formation with higher permeability. In order to isolate water influxes, it is necessary to create the strong tight barrier around the borehole. It is impossible to create this barrier using cement suspension in the porous formations due to comparability of the cement particles and the pore channel size. It is also problematic to develop the barrier using sediment forming compositions, because it is impossible for pores to be clogged by the sediments. The most suitable method on devoloping of the impermeable barrier in those formations is gelling of the bottom-hole with subsequent forming of the strong gel within a certain time interval. The mix of waterglass and hydrochloric acid solution will meet those requirements. Experimental researches for the gel parameters have been carried out. It is shown that gel consists in half from 10% water glass solution and 10% hydrochloric acid solution has gel strength t0=3000-5000 Pa, what provides the strength of the barrier under 20 Mpa/m pressure differential which is much greater that the actual ones. On the basis of the researches the water influx isolation method has been devoloped. This method has been tested and applied with getting of positive results in 5 wells of Balakhanineft oil-and-gas production department.
