Surfactant flooding, a chemical IOR technique is one of the viable EOR processes for recovering additional oil after water flooding. This is because it reduces the interfacial tension between the oil and water and allows trapped oil to be released for mobilization by a polymer.In this research, two sets of experiments were performed. First, the optimum surfactant concentration was determined through surfactant polymer flooding using a range of surfactant concentration of 0.1% to 0.6% and 15% of polymer. Secondly, another set of experiments to determine the optimum flow rate for surfactant flooding was carried out using the optimum surfactant concentration obtained. Lauryl Sulphate (Sodium Dodecyl Sulphate, SDS), an anionic surfactant, was used to alter the interfacial tension and reduce capillary pressure while Gum Arabic, an organic adhesive gotten from the hardened sap of the Acacia Senegal and Acacia Seyal trees, having a similar molecular structure and chemical characteristics with Xanthan Gum, was the polymer used to mobilize the oil.The results show that above 0.5%, oil recovery decreases with increase in concentration such that between 0.5 and 0.6%, a decrease of (20% -19%) is recorded. This suggests that it would be uneconomical to exceed surfactant concentration of 0.5%. It is shown in the result of the first set of experiments that a range of oil recovery of 59% to 76% for water flooding and a range of 11.64% to 20.02% additional oil recovery for surfactant Polymer flooding for a range of surfactant flow rate of surfactant concentration of 0.1% to 0.6%. For the second sets of experiments, a range of oil recovery of 64% to 68% for water flooding and a range of 15% to 24% additional oil recovery for surfactant flooding for a range of surfactant flow rate of surfactant flow rate of 1cc/min to 6cc/min. The Optimum surfactant flow rate resulting in the highest oil recovery for the chosen core size is 3cc/min. It's highly encouraged that the critical displacement rate is maintained to prevent the development of slug fingers.In summary, an optimum Surfactant flow rate is required for better performance of a Surfactant flooding.

Chemical flooding methods are used to recover residual oil left after water flooding. Several chemical flooding processes have been used to improve recovery. Alkaline-free surfactant polymer combination flooding (SP flooding) can avoid side-effects encountered in alkali-surfactant-polymer (ASP flooding) combination flooding. As part of the ongoing research on the use of Gum Arabic as a polymer in chemical flooding in Nigeria, this paper investigates the effect of heavy oil viscosity on oil recovery during SP flooding.Improved oil recovery through SP flooding was studied by conducting linear displacement experiments using engineering grade class IV glass beads. The glass beads were treated to be strongly water wet. The viscosity of oil samples used for the different experiments ranged from 3 to 140 cp. Lauryl Sulphate and Gum Arabic were used as the surfactant and polymer respectively.Result shows that oil recovery by water flooding ranges from 15% -25% and for SP 15% -35% keeping the polymer concentration constant. Thus, increasing oil recovery can be achieved as the viscosities of oil increases. The result from this study will help develop effective methods for implementing SP flooding using Gum Arabic that is vastly available in Nigeria in heavy oil fields. It will give the oil industry a new option for improving oil recovery from heavy oil reservoirs. SP flooding will be handy to improve oil recoveries from many marginal oil fields in Nigeria or those that face shut-down due to uneconomic operating cost, but still contain significant amount of oil.

A Laboratory Study of ASP Flooding on Mixed Wettability for Heavy Oil Recovery Using Gum Arabic Polymer Alkaline-Surfactant-Polymer (ASP) flooding process offers a promising approach to recover the residual oil which often times is more than 50% of original oil in place.This paper presents the summary of the laboratory studies on the effect of wettability on oil recovery of Alkaline/Surfactant/Polymer flooding using a Local Polymer -Gum Arabic which is vastly available in Nigeria. Engineering grade class IV glass beads were treated with chemicals to water-wet (WW) and oil-wet (OW) conditions. Different degrees of wettability were obtained by mixing the WW and OW glass beads in different ratio before each flooding experiment. The mixing ratio used were 100%WW and 0%OW; 75%WW and 25%OW; 50%WW and 50%OW; 25%WW and 75%OW; 0%WW and 100%OW. The displacement efficiency of Alkaline/Surfactant/Polymer flooding and Polymer flooding at the different wetting conditions was evaluated by laboratory coreflood experiments.From the experimental result, it was also observed that oil recovery increases as formation becomes more strongly water wet. The experiment results indicate that the displacement efficiency of water floods and ASP flooding is markedly affected by the wettability of the core. The wettability is one of the important factors to determine the oil recovery of water and ASP flooding. Water-wet and oil-wet conditions are favourable to obtain high enhanced oil recovery for ASP flooding using locally available Gum Arabic.

Polymer play a key role in several EOR processes such as polymer flooding, surfactant-polymer flooding and alkaline-surfactant-polymer flooding due to their critical importance of mobility control in achieving high oil recovery. This high oil recovery is dependent on polymer properties and the rate of flooding. This paper presents the results of polymer flooding of an unconsolidated porous media using the locally available Gum Arabic in its natural and Modified states. Commonly used polymers Xantham Gum and Hengfloc were also used for comparison. The effective flooding rate was established using Modified Gum Arabic as the polymer. The established flow rate was used in polymer flooding for other polymers. Different concentration of each polymer was used to achieve similar viscosity of polymer solutions used for each flooding. The brine, oil and porous media properties were also kept constant. The results from these studies favoured a low injection rate. More oil up to 90% of original oil in place was recovered. The result from the oil recovery using the established effective rate on other polymers showed that the Modified Gum Arabic recovers approximately 10% more than the natural Gun Arabic, Xantham Gum and Hengfloc. The recoveries were 90.2%, 81%, 79.5% and 80.2%, respectively. It was also observed that the oil retention time in polymer mixture is lower in Modified Gum Arabic and Natural Gum Arabic when compared to Xantham Gum and Hengfloc.

In order to improve the efficiency of the enhanced oil recovery process, researchers have come up with different methods such as mobility control, chemical, miscible, thermal and other processes such as microbial. In chemical flooding for example, alkaline, polymer, surfactant, surfactant polymer (SP) and alkaline surfactant polymer (ASP) have all been employed in the quest for better efficiency. However, grain size effect on the recovery system during these tertiary recovery techniques has received less attention over the years. This paper presents evaluation of the effects of grain size on residual oil saturation (ROS) from experimental studies of oil recovery potentials of a formulated ASP slug in synthetic porous media. 1% weight of sodium hydroxide (NaOH), 0.15% weight of shell enordet 0242 supplied by shell research centre and 0.02% weight of hengfloc 63020 were used as alkali, surfactant and polymer respectively. Ranges of core grain sizes of 0.063 to 0.090, 0.106 to 0.150, 0.150 to 0.212, 0.212 0.300 and 0.425 to 0.600 micron were considered in five different experiments performed. Each of the experiment was accomplished by a procedural sequence of brine saturation, oil saturation, water flooding and ASP flooding. The results show that the porosity of the synthesized core increases with decreasing grain size from 37.2% to 43.74% for a range of 0.600 micron to 0.063 micron of sizes. The permeability of the synthetic core decreases from 2309 millidarcy to 669 millidarcy as the grain size decreases from 0.600 micron to 0.063 micron. Pressure drop across the beads pack increases from 0.294 psi to 1.015 psi as the grain size reduces. The oil recovery by an immiscible fluid through the beads pack increases as the pore throat get smaller or the grain size reduces. The volume of ROS after flooding reduces as grain size reduces.

In order to improve the efficiency of the enhanced oil recovery process, researchers have come up with different methods such as mobility control, chemical, miscible, thermal and other processes such as microbial. In chemical flooding for example, alkaline, polymer, surfactant, surfactant polymer (SP) and alkaline surfactant polymer (ASP) have all been employed in the quest for better efficiency. However, grain size effect on the recovery system during these tertiary recovery techniques has received less attention over the years. This paper presents evaluation of the effects of grain size on residual oil saturation (ROS) from experimental studies of oil recovery potentials of a formulated ASP slug in synthetic porous media. 1% weight of sodium hydroxide (NaOH), 0.15% weight of shell enordet 0242 supplied by shell research centre and 0.02% weight of hengfloc 63020 were used as alkali, surfactant and polymer respectively. Ranges of core grain sizes of 0.063 to 0.090, 0.106 to 0.150, 0.150 to 0.212, 0.212 0.300 and 0.425 to 0.600 micron were considered in five different experiments performed. Each of the experiment was accomplished by a procedural sequence of brine saturation, oil saturation, water flooding and ASP flooding. The results show that the porosity of the synthesized core increases with decreasing grain size from 37.2% to 43.74% for a range of 0.600 micron to 0.063 micron of sizes. The permeability of the synthetic core decreases from 2309 millidarcy to 669 millidarcy as the grain size decreases from 0.600 micron to 0.063 micron. Pressure drop across the beads pack increases from 0.294 psi to 1.015 psi as the grain size reduces. The oil recovery by an immiscible fluid through the beads pack increases as the pore throat get smaller or the grain size reduces. The volume of ROS after flooding reduces as grain size reduces.

Among the world's natural sources of energy, petroleum stands out as the largest contributing mineral. This makes it the most sought-after mineral. Methods for oil recovery are constantly studied, and innovations are being made to improve the recovery of oil. Chemical Enhanced oil recovery (EOR) process is therefore at the fore-front of these studies and innovations.The research work presents a comparative study of the core flooding carried out with different Alkali/Surfactant/Polymer (ASP) slugs formulated using sodium hydroxide (NaOH) an alkaline, surfactant being Lauryl Sulphate and Shell Enordet and polymer-gum Arabic and Xanthan gum.The result shows that the ASP slug of Xanthan gum with Shell Enordet 0242 and Lauryl Sulphate had the highest displacement efficiency of 71.23% and 49.51% respectively. The others ASP slug formulated with gum Arabic and Shell Enordet or Lauryl Sulphate gave an efficiency of 31.36% and 32.20% respectively.For heavy Oil recovery, the use of Shell Enordet 0242 or Lauryl Sulphate and Xanthan gum or gum Arabic will improve recovery. However, Xanthan gum gave a more stable displacement front than gum Arabic. Therefore, a higher concentration of gum Arabic is recommended for better recovery.

Relative permeability is one of the key factors in reservoir engineering calculations to simulate multiphase behavior in porous media. The relative permeabilities calculated from established models do not perfectly characterize the reservoir without a known trend or history. This necessitates the need to use a reliable and globally accepted technique based on Niger Delta field production data for calculating relative permeabilities from the fields so that the models derived from the relative permeability curves could be tamed and domesticated in the region for better reservoir characterization and evaluation. The Johnson, Bossler and Neumann (JBN) method is the industry standard for measuring relative permeabilities from field cores. In order to eliminate the need of using numerical differentiation, and therefore reduce the overall numerical error in this method, a graphical technique was proposed and implemented during late 70s. However, with splines, the numerical differentiations are still done but with improved results. The current study presents the results from the comparative analysis of two approaches employed to avoid the traditional numerical differentiation required by the JBN method. Production data from field cores in the Niger Delta were used. The graphical method and cubic spline numerical modeling were both used to calculate the individual relative permeabilities from the pressure/production history of the displacements. the results were analyzed and compared. The results of both methods show a very good match over a fairly small saturation range and also differ. However, cubic spline results are closer to the traditional numerical differentiation results because is a modeling approach in which the numerical differentiation is incorporated with improved accuracy.