Jeff Dupont, Rick Mitchell, and Jeff Dawson
Innospec Oilfield Services
Reservoirs having clays that swell/migrate can potentially impair production. When these clays are present, it is advantageous to use clay stabilizers to mitigate this damage potential. The industry has adopted several clay assessment methods including analytical procedures such as XRD, SEM and performance testing methods such as capillary suction test (CST) and roller oven test. This paper will describe a new performance test method for inhibitors used in shale reservoirs that complements the existing methods. A modified core flow method has been developed using unconsolidated core material that indirectly measures the clay swelling and migration potential. In this procedure, a packed column composed of tightly-sized shale material is used to simulate an infinite fracture network. Treatment fluids are then pumped through the column at constant rate while measuring pressure drop. The relative pressure change, together with the turbidity of the effluent, allows easy assessment of the clay stabilizer.