Abstract
Poor formation permeability and near well bore damage may limit water injectivity into the reservoir in a water injection project. This paper seeks to evaluate the effect of radial drilling technique on water injectivity and oil recovery in water flooding operation. Radial drilling technology utilizes hydraulic energy to create lateral perpendicular small holes through the casing into the reservoir. The holes may extend to 100 m (330 ft) into the reservoir to access fresh formations beyond the near wellbore, and damage zone. A black oil simulator (Eclipse 100) was used to modeling a lateral radial drill from the borehole into the reservoir, and that of a conventional perforation of the wellbore respectively. A simulation study was carried out using various presumed radial drill configurations in determining injectivity index, displacement efficiencies, recovery factor and water cut of the process. The determined results were further compared with that of the conventional perforation process case respectively. The results show a significant improvement in water injectivity in radial drill case with the increasing length and number of radials as compared to the conventional wellbore perforation case. The determined Recovery factor shows a progressive increase with increase in the numbers of radials drilled, irrespective of the radial length. However, it was observed that, the more the number and length of the radials drilled in to the reservoir, the higher the water cut from producer wells. Radial Drilling Technology, therefore, has a promising potential to improving water injectivity into the reservoir and thereby optimizing oil recovery in a water flooding operation.
Theoretical and experimental study of the pulling force of jet bits in radial drilling technology