The huge part of remaining recoverable reserves of oil in Perm region is concentrated in complex structured stratified carbonate reservoirs. Thus, the task of improving the efficiency of oil field development and providing good control and adjustability of the field development process in the condition of intermittent production is complicated with the increase of watercut while the recovery of reserves. That is why the approaches to bottomhole treatment and candidate wells selection are complicated. The importance of accurate fluid placement during acid treatment is increased. The bottomhole treatment often needs flow-diverters for successful acidizing.
The approaches and main results of laboratory testing of self-diverting acid systems and flow-diverters for complex acid treatments in stratified irregular reservoirs are given in the article. There is shown that self-diverting acid systems based on viscoelastic surfactants demonstrate an effect of flow diversion while the low value of permeability contrast. Decreasing of acid content in self-diverting acid system increases the effect of flow diversion due to increasing of viscosity of the acid while spending of acid. Flow-diverters based of invert emulsions have the high initial viscosity that’s why such kind of systems demonstrate the strong effect of flow diversion in case of higher irregularity and permeability contrast. Recommendations of using different flow-diverting systems for objects with different properties of reservoir based on laboratory tests are formulated. Regarded technologies are widely used in Perm region.
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