The linear core flood (physical model) has been used severally in the past to conduct laboratory researches and experiments on Tertiary Oil Recovery. A potential pitfall of the 1D nature of the linear core flood arises during waterflooding; water channels would be blocked due to limited pathways, hence producing the additional oil before chemical consequently breaks through. In real reservoirs, there are more water pathways present; hence the relative impact of these chemical additives on incremental oil recovery is potentially overly emphasized in the laboratory. This paper presents a study on heavy oil production using chemicals in a locally fabricated 2D Hele-Shaw cell system. The 2D nature of the cell also aids the visualization of non-linear flow pathways. The experiments are run for a constant pore volume (5PV) flooding of Brine, Surfactant slug and Surfactant-Polymer (SP) slug. Recovery and digital images are taken at a minute interval each, thereby making it easier to study growth and distribution of fingers before and after water or chemical breakthrough. It was observed that after the 5PV of waterflooding, the recovery of oil from the cell reduced gradually till there was no more recovery. The Surfactant slug increased recovery by additional 21%. The more viscous Surfactant-Polymer slug gave an even improved and better recovery. This can be attributed to a clear interaction between the Surfactant and Polymer chemicals in the SP slug. The distribution of fingers between the different phases of flooding were visually observed and compared.

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.

Over the years, drillstring vibrations have become a major issue in the oil and gas industry. The search for energy has led operators to encounter various unconventional conditions such as high temperature, high pressure, etc. in their quest for oil and gas. Drillstring vibrations amongst other problems are regularly encountered in such conditions, leading to tool damage, increased downtime and other adverse problems. In this work, an analytical approach was adopted to investigate the major parameters that affect drillstring vibrations and a viable control method was recommended. The vibration models were analyzed and a modified model was developed to fit the standard drilling conditions, starting from the top of the drillstring down to the formation being drilled. Considering the Parameters which were often neglected in the works of this nature such as mud density and formation fracture pressure were investigated in order to understand the extent of their contributions to drillstring vibrations. Using standard drilling conditions for the simulations, we were able to identify the key parameters which significantly affected the vibration profiles. The data obtained from the simulations were used to obtain a markedly better profile which showed a marked reduction in amplitude. The analysis of the effect of all considered parameters to the vibration profile led to the conclusion that weight on bit / torque on bit and rotary speed are the key factors that affect drill-string vibrations and that the density of the drilling fluid used make little or no difference why formation fracture gradient caused a reduction in drillstring vibration as it increases.