METHOD FOR FIGHTING AGAINST SAND INGRESSION IN PRODUCTIVE STRATA Russian patent published in 1996 - IPC

FIELD: geological operations. SUBSTANCE: in liquid and gas production from underground geological strata composed of loose and uncemented sand particles, reliable stabilization of filtering material with retaining its permeability is achieved by pumping mixture of solid resilient particles. Resilient particles compose 50-95% of filtering material volume. In process of pumping, resilient particles reach downhole zone in compressed and stressed condition. Upon pumping, as pressure drops, resilient particles wedge unresilient ones but volume of filtering material remains uncharged through it becomes densified and strengthened. Flexible permeable layer is formed around operating tube string. It solidifies unstable ground and prevents ingression of sand into hole. For better performance of productive stratum, filtering material at end of operation is pumped at pressure twice and more higher than in operation. EFFECT: high efficiency. 2 cl, 1 tbl