A Comparative Analysis of Waterflooding Projects using Horizontal Wells

Abstract

Abstract The use of horizontal and multilateral wells in oil industry has increased rapidly during the last two decades.The main reason for this upsurge is that horizontal and multilateral wells provide large contact area with the reservoir, and therefore enhance the well productivity or injectivity better than conventional vertical wells.The high productivity coupled with the recent advances in drilling technology for horizontal and multilateral wells has made their application to be an economically viable option. In this study, the performance of non-conventional wells in water flooding projects was investigated using numerical simulation techniques.Extensive three-dimensional, fine-mesh simulation runs are performed to determine the oil recovery by non-conventional wells under different operating/reservoir conditions.Results show that the pattern used has a significant effect on the displacement performance of non-conventional wells.The study shows the various conditions under which non-conventional wells will perform better than the use of conventional vertical wells Introduction The primary oil recovery mechanisms when are exhausted, leave enormous quantities of oil un-recovered.The advancement of oil recovery is a cardinal obligation in the oil industry.From waterflooding to various thermal recovery operations, the predominant objective of the improved oil recovery processes is to increase the rate of recovery and the ultimate production from reservoirs. Waterflooding is one of the more widely used improved oil recovery techniques.The injected water provides a drive mechanism to recover more oil. During the last two decades, the oil industry has experienced an upsurge in the number of horizontal and multilateral wells being drilled. The use of horizontal and multilateral wells instead of vertical ones improves the performance of waterflooding projects in terms of productivity, reduce gas and/or water coning problems, and increase the sweep efficiency. Although many studies have focused on the use of horizontal and multilateral wells in exploiting a reservoir, there are only limited studies dealing with the use of these wells in water flooding projects.Ozkan and Raghaven developed an approximate analytical method to predict the breakthrough time for both horizontal and vertical wells[1].Pieters and Al-Khalifa investigated the use of horizontal and vertical wells in water flooding a layered heterogeneous carbonate reservoir[2].They showed that horizontal and vertical wells recovered the same amount of oil in tight facies given that the vertical well penetrating the entire reservoir thickness.Islam et al. studied the use of horizontal wells to electromagnetic heat reservoir[3].Their simulation results show oil recovery as high as 60% of the oil in place. Folefac et al. studied the effect of pressure drop along wellbores on the performance of horizontal well[4]. They indicated that some parameters, such as well length, diameter and perforated interval, have significant effects on the pressure drop in the wellbore.