Innovative Solutions to Fines Management in High Permeability Sands
Formation impairment due to fines migration during drilling and production continues to cause injectivity or inflow reduction. In high permeability sandstone formations or sandpacks, fines migration pose major concerns in the oil industry as it leads to reduction in oil/gas production. The problem is further enhanced in mature reservoirs where increased water ingress and multiphase production aggravate the fines mobilisation and migration. Proper fines management can optimise productivity, safeguard facilities and reduce well maintenance cost. Today’s core flood tests as part of risk assessment limit tests to single phase or at best two-phase oil/water flow. This paper presents the unique technique adopted to analyse fines migration mechanisms in a true multiphase environment. The technique integrates CFD and 3-D reservoir simulation concepts to define and quantify the effects of different operating conditions on discretised reservoir blocks. From the results obtained detailed mapping of prevailing pore blocking mechanisms and corresponding impairment profiles are presented as functions of operating conditions and completion strategies. The paper introduces a parallel experimental programme being initiated at The Robert Gordon University(RGU) to validate the simulation predictions. The paper is concluded with suggestions (supported by flow efficiency case studies) on contemporary innovations in fines management ranging from a radical use of expandable screens (ESSTM) or expandable slotted liners (ESLTM) or the intelligent VSSTM Screen to specialist application of glass or ceramic beads for pore diameter control and near wellbore reinforcement to initiate secondary filtration