Water Coning Prediction Review and Control: Developing an Integrated Approach

In petroleum industry, oil production strategy to circumvent water coning in reservoirs with strong water drive is quit challenging. To ameliorate this oil production related problem, several water coning prediction models and control approaches have been developed by researchers. The prediction approaches include analytical, empirical and numerical approach. The analytical and empirical prediction approaches are qualitative water coning prediction approach with limited field scale application. However, these approaches model predictions can gain field application if upscale. Numerical approach has provided the fulcrum to study the complexity of water coning phenomenon in bottom-water drive reservoirs, and its prediction and sensitivity results have found wide field application. In addition, the various developed water coning control methods: downhole oil-water separation (DOWS), downhole water sink (DWS), downhole water loop (DWL), among others have proved to be effective, as it reduces the water-cut, produced water and water handling problem at the surface during hydrocarbon production. However, the challenge of producing the bypassed oil in the reservoir remains unattended with these coning control methods. Also, even as effective as these water coning control methods may seems, they have their drawbacks that limit their application in certain reservoirs. Therefore, developing integrated approach that is adaptive to control water coning and produce bypassed oil in bottom-water drive reservoirs is important to the oil and gas industry

A Comparative Study of Diesel Oil and Soybean Oil as Oil-Based Drilling Mud

Oil-based mud (OBM) was formulated with soybean oil extracted from soybean using the Soxhlet extraction method. The formulated soybean mud properties were compared with diesel oil mud properties. The compared properties were rheological properties, yield point and gel strength, and mud density and filtration loss properties, fluid loss and filter cake. The results obtained show that the soybean oil mud exhibited Bingham plastic rheological model with applicable (low) yield point and gel strength when compared with the diesel oil mud. The mud density measurement showed that soybean OBM was slightly higher than diesel OBM with mud density values of 8.10 lb/gal and 7.98 lb/gal, respectively, at barite content of 10 g. Additionally, the filtration loss test results showed that soybean mud fluid loss volumes, water and oil, were 13 mL and 10 mL, respectively, compared to diesel oil mud volume of 15 mL and 12 mL. Furthermore, the filtration loss test indicated that the soybean oil mud with filter cake thickness of 2 mm had a cake characteristic of thin and soft while the diesel oil mud resulted in filter cake thickness of 2.5 mm with cake characteristic of firm and rubbery. In comparison with previous published works in the literature, the soybean oil mud exhibits superior rheological and filtration property over other vegetable oil-based muds. Therefore, the formulated soybean oil mud exhibited good drilling mud properties that would compare favourably with those of diesel oil muds. Its filter cake characteristic of thin and soft is desirable and significant to avert stuck pipe during drilling operations, meaning that an oil-based drilling mud could be formulated from soybean oil

Interpretation of Neural Network Models – New Insights of Estimating Static Bottom-Hole Pressures of Gas Wells in Nigerian Petroleum Provinces

Methods to determine static bottom-hole pressure (BHP) from surface measurements include the average temperature and z-factor method, the Sukkar-Cornell method, the Cullender-Smith method, and the Poettmann method. Among these methods, the Poettmann method is preferable in the petroleum industry but with a concern for software developers, as the integral values to determine the static BHP are tabular. In this study, neural network-based models to predict the integral values using pseudo-reduced pressures and temperatures were developed. The 2-3-1, 2-4-1, and 2-5-1 neural-based models had overall correlation coefficients (R) of 0.9974, 0.99835, and 0.99745, respectively, for the maximum-minimum normalization method and R of 0.99745, 0.99805, and 0.9992 for the clip-scaling method. Comparing the models' predictions with the Lagrangian interpolated values resulted in R of 0.99895 and 0.9995 for the maximum-minimum and clip-scaling-based models. Thus, the developed models can predict Poettmann's integral values without table look-up to estimate static BHP in gas wells

The Impact of Intestinal Parasitic Infections on the Nutritional Status of Rural and Urban School-Aged Children in Nigeria

Objectives:Intestinal parasitic infection and undernutrition are still major public health problems in poor and developing countries. The objective of this study was to assess the relationship between intestinal parasitic infection and nutritional status in 405 primary school children from rural and urban areas of Akwa Ibom State, Nigeria.Methods:This cross-sectional survey in 2009 obtained anthropometric data, height-for-age (HA), weight-for-height (WH) and weight-for-age (WA) Z-scores from each child and fecal samples were also collected and screened for intestinal parasites using standard parasitological protocols.Results:The prevalence of infection with any intestinal parasite was 67.4%. A total of six intestinal parasites were detected; hookworm (41.7%) had the highest prevalence. The prevalence of intestinal parasites and undernutrition was significantly higher in rural than in urban children (P<0.001). The prevalence of stunting (HAZ < -2), underweight (WAZ < -2) and wasting (WHZ < -2) for rural and urban children were 42.3% vs. 29.7%; underweight 43.2% vs. 29.6% and wasting 10.9% vs. 6.4%, respectively. With respect to nutritional indicators, the infected children had significantly (P<0.05) higher z-scores than the uninfected children. Multivariate logistic regression analysis showed that only Hookworm and Ascaris lumbricoides were each significantly (P<0.05) associated with stunting, wasting, and underweight.Conclusions and Public Health Implications:Since intestinal parasitic infections are associated with malnutrition, controlling these parasites could increase the physical development and well-being of the affected children

The Impact of Intestinal Parasitic Infections on the Nutritional Status of Rural and Urban School-Aged Children in Nigeria

Objectives Intestinal parasitic infection and undernutrition are still major public health problems in poor and developing countries. The objective of this study was to assess the relationship between intestinal parasitic infection and nutritional status in 405 primary school children from rural and urban areas of Akwa Ibom State, Nigeria. Methods This cross-sectional survey in 2009 obtained anthropometric data, height-for-age (HA), weight-for-height (WH) and weight-for-age (WA) Z-scores from each child and fecal samples were also collected and screened for intestinal parasites using standard parasitological protocols. Results The prevalence of infection with any intestinal parasite was 67.4%. A total of six intestinal parasites were detected; hookworm (41.7%) had the highest prevalence. The prevalence of intestinal parasites and undernutrition was significantly higher in rural than in urban children (P<0.001). The prevalence of stunting (HAZ < -2), underweight (WAZ < -2) and wasting (WHZ < -2) for rural and urban children were 42.3% vs. 29.7%; underweight 43.2% vs. 29.6% and wasting 10.9% vs. 6.4%, respectively. With respect to nutritional indicators, the infected children had significantly (P<0.05) higher z-scores than the uninfected children. Multivariate logistic regression analysis showed that only Hookworm and Ascaris lumbricoides were each significantly (P<0.05) associated with stunting, wasting, and underweight. Conclusions and Public Health Implications: Since intestinal parasitic infections are associated with malnutrition, controlling these parasites could increase the physical development and well-being of the affected children. Key Words: Intestinal parasites • malnutrition • children • rural-urban • Nigeria