(242b) Effect of Nanoporous Monoliths on Saturation Pressure in Shale Reservoirs

Shale reservoirs are now becoming the focus of new oil and gas exploration and development. These shale reservoirs usually have lower permeability and porosity with a pore size distribution ranging between 1-20 nm. It is hypothesized that fluids in the confined systems (shale reservoirs) have different thermo-dynamic properties than conventional reservoirs. However, because of the difficulty of the realization of the pore structure of shales, there have been few experimental studies. In my research, two different nanoporous silica based monoliths were synthesized with similar pore size ranges as the shale reservoirs, represented in the porous system of shale reservoirs. Monoliths can be synthesized into a desired shape by putting them in a customized container. Because of this advantage, the synthesized monoliths have only nano-sized pores, not macropores. Two nanoporous monoliths were synthesized by modifying the synthesizing procedures that could be used to synthesize hexagonal and cubic mesoporous silica powders, which have different morphologies. From comparing the saturation pressure with and without nanoporous media, we can confirm the hypothesis that nano-sized pores have an effect on saturation pressure. Also, we can see the different morphologies of the two monoliths have an effect on saturation pressure. These synthesized monoliths have been characterized by X-ray diffraction (XRD), nitrogen adsorption/desorption isotherm (BET), and transmission electron microscopy (TEM), which show their physicochemical properties. The phase diagram of methane and decane mixture has been modeled with the Winprop module from the CMG reservoir simulator. The experimentally measured saturation pressure matches with the simulated result. However, the measured saturation pressure changes with nanoporous media.