Laboratory study of miscible carbon dioxide flooding of UAE carbonate oil reservoirs

This laboratory study describes the technical feasibility of applying C0₂ miscible flooding in a major field in Abu Dhabi, UAE. The field section considered is a low permeability carbonate that had so far poorly responded to water flooding.The study had two major aspects, phase behavior and core flooding. In phase behavior, the field's petroleum was studied with its minimum miscibility pressure with C0₂ determined. Also, asphaltene precipitation due to C0₂ injection was measured ami included in the phase behavior model. In core flooding, detailed rock characterization was carried out using SEM, EDS, ami ICP. Thereafter, core floods were carried out to evaluate the additional recovery from miscible C0₂ injection and the optimum C0₂ slug sizes. Core floods were also used to evaluate recoveries from different initial saturations, for less than miscible conditions, and for side effects such as asphaltene precipitation, sulfur deposition, and effect of C0₂ on the limestone rock.