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.

Background Diabetes mellitus is highly prevalent and associated with huge economic burden globally. The conventional care and management of diabetes mellitus is highly fragmented and complex, warranting the need for a comprehensive Collaborative Care Model (CCM). Little is known about the perception of patients with diabetes and their healthcare providers about CCM, its barriers and facilitators. This study aimed to explore the value of CCM in diabetes care at a primary healthcare (PHC) setting from the perspective of patients with diabetes and healthcare professionals (HCPs), in an effort to expand our current knowledge on collaborative care in diabetes at primary care level for the purpose of quality improvement and service expansion. Methods Using an exploratory case study approach, semi-structured interviews were conducted among patients and HCPs who encountered CCM in Qatar during 2019 and 2020. The semi-structured interviews were transcribed verbatim and the data were analysed and interpreted using a deductive-inductive thematic analysis approach. Results Twelve patients and 12 HCPs at a diabetes clinic participated in one-to-one interviews. The interviews resulted in five different themes: the process and components of collaborative care model (four subthemes), current organizational support and resources (three subthemes), impact of collaborative care model on diabetes outcomes (three subthemes), enablers of collaborative care model (three subthemes), and barriers to collaborative care model (three subthemes). The participants indicated easy access to and communication with competent and pleasant HCPs. The patients appreciated the extra time spent with HCPs, frequent follow-up visits, and health education, which empowered them to self-manage diabetes. HCPs believed that successful CCM provision relied on their interest and commitment to care for patients with diabetes. Generally, participants identified barriers and facilitators that are related to patients, HCPs, and healthcare system. Conclusions The providers and users of CCM had an overall positive perception and appreciation of this model in PHC settings. Barriers to CCM such as undesirable attributes of HCPs and patients, unsupportive hospital system, and high workload must be addressed before implementing the model in other PHC settings.

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.

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Flocculation occurs when particles in the drilling fluid agglomerate due to particle to particle attraction thus leading to uneven distribution of weighting material within the fluid. Dispersants majorly are used to deffloculate fluids that have these tendencies, and their performance lies in the ability to minimize sagging and hence control drilling fluid rheology(Yusuf et al). This work was undertaken to investigate the effect of clay and sea water (containing calcium and magnesium ions) contaminations on dispersant performance used in an oil based invert emulsion drilling fluid system. Barite (Ba2SO4) was used as the weighting agent; the based fluid used for the oil based invert emulsion mud was EDC-99, a specialized kind, different from the conventional diesel oil.The fluid were analysed before and after aging using, rheometer, filtration and emulsion stability tests. The dispersant employed for the fluid system was Versathin ®. Versathin is an oligomeric fatty acid in mineral oil, an oil-based dispersant which tend to also perform excellently in the invert emulsion system. From the experimental results, a general decrease in fluid rheology was observed in the dispersant sample as compared with the blank sample. The emulsion stability of the fluid decreased as contaminants were added, fluid loss increased when contaminants were added to the dispersant samples. Contaminations also increased the plastic viscosity and yield point for the dispersant sample but all were still within the API range. Increase in LSYP in the presence of sea water and clay revealed that sag may be less noticeable when drilling reactive formations, confirming earlier studies on water based mud and the suitability of clay as rheology controllers. Cumulatively the result shows that Versathin oil based dispersant can control flow behaviour of fluids when employed in the oil based invert emulsion system.

Background: Diabetes mellitus (DM) is one of the top health priorities in Qatar due to its high prevalence of 15.5%, which is projected to increase to 29.7% by 2035. DM management is still challenging despite healthcare advancement, warranting the need for a comprehensive Collaborative Care Model (CCM). Therefore, we aim to evaluate the value of CCM in DM care at a primary healthcare (PHC) setting in Qatar. Methodology: This study was a qualitative exploration of healthcare professionals’ (HCPs’) and patients’ perspectives on the value of CCM provided at the center. Twelve patients and twelve HCPs participated in semi-structured one-toone interviews. Qualitative data were analyzed and interpreted using a deductive coding thematic analysis process. Results: The interviews resulted in 14 different themes under the predefined domains: components of CCM (five themes), the impact of CCM (three themes), facilitators of CCM provision (three themes), and barriers of CCM provision (three themes). The majority of the participants indicated easy access to and communication with HCPs at QPDC. Participants appreciated the extra time spent with HCPs, frequent follow-up visits, and health education, which empowered them to self-manage DM. Generally, participants identified barriers and facilitators related to patients, HCPs, and healthcare system. Conclusion: The providers and users of CCM had an overall positive perception and appreciation of this model in PHC settings. Barriers to CCM such as unpleasant attitude and undesirable attributes of HCPs and patients, unsupportive hospital system, and high workload must be addressed before implementing the model in other PHC settings.

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