Nicolet 6700 fourier transform infrared spectrometer ftir

A Brookfield viscometer, Brookfield company (Middleboro, MA, USA); RS-600HAAKE rheometer, Haake company (Karlsruhe, Germany); Nicolet 6700 Fourier Transform Infrared Spectrometer (FTIR), Thermo Fisher company (Waltham, MA, USA); DSC823 Differential Scanning Calorimeter, Mettler Toledo company (Zurich, Switzerland); and Anton-Paar Dynamic Mechanical Analyzer, Anton-Paar company (Graz, Austria), were used. A conventional physical simulation displacement experimental apparatus, Hai’an Petroleum Research Instruments Co., Ltd. (Hai’an, China), was used. For the plugging experiments, a visually observable fracture model was created to simulate reservoir fractures. This fracture model was formed by bonding two pieces of frosted glass along the sides by using epoxy resin adhesive. The aperture of the fracture was controlled by filling rubber bands with different sizes on the fracture surface. The parameters of the fractures used in the experiment are shown in Table 1. The temperature of the displacement experiment is 45 °C, and the injection rate of the fluid is 0.5 mL/min. The inlet of the fracture model is connected to a pressure sensor, and the inlet pressure is automatically recorded by the computer. The outlet of the fracture model is connected to the atmosphere. The pressure difference (ΔP) at both ends of the fracture model is numerically equal to the inlet pressure.