This research examined the technical and economic feasibility of harnessing flare gas emissions from oil fields. The outcome would provide the basis for a substantial re-utilization of this waste energy due to the current practice of flaring and use it alternatively as energy for powering oil fields, rural electrification and desalination. Nigeria is used as a case study. Burning fossil fuels have grave environmental impact, amidst increasing global concerns over harmful emissions. This research addresses resource decline and suggests divestment as a partial cure. The gas turbine is subject to degradation of its components as it is used. Though several methods of assessing gas turbine degradation have been developed with varying degrees of success, no one method has addressed issues pertaining to associated gas and its effects on degradation with divestment. Simulation of two single shaft, heavy duty industrial gas turbines; and three aero-derivative industrial gas turbines of the heavy medium and light capacity ranges were carried out for varying operating conditions, to ascertain the effects of degradation when run on associated gas. Thereafter, optimizations for the best power plant engine mix and the least cost of electricity were carried out. Genetic algorithm was used to assess a population of 10,000 individuals over 500 generations; convergence was achieved for different configurations of the five study engines at discount rates of 5% and 10%, over three power ranges. The divestment pattern starts with the lightest aero-derivative industrial gas turbine; the best power plant selection was limited to the two lightest aero-derivatives in the fleet, completely ignoring the heavy engines. A techno-economic, environmental and risk assessment model comprising performance, emission, economics and risk modules was successfully developed to assess gas turbine degradation with divestment. Using this tool, it was confirmed that associated gas usage resulted in degradation of gas turbine performance, an increase in gas collection as well as operation and maintenance costs. Also there was increasingly higher creep life consumption during slow, medium and fast degradation scenarios for both engine sets. The novel technical contribution of the research work therefore is the influence of degradation on the economic use of associated gas as fuel in gas turbine power generation; and the implementation of divestment in the face of fuel decline.

The aim of this study was to determine the change in working length (∆WL) before and after coronal flaring and after complete rotary instrumentation as a function of canal curvature. One mesiobuccal or mesiolingual canal from each of 43 extracted molars had coronal standardization and access performed. Once the access was completed, canal preparation was accomplished using Gates Glidden drills for coronal flaring and EndoSequence files for rotary instrumentation. WLs were obtained at 3 time points: pre-instrumentation (unflared), mid-instrumentation (flared) and post-instrumentation (concluded). Measurements were made via direct visualization (DV) and the CanalPro apex locator (EM) in triplicate by a single operator with blinding across the time points. Root curvature was measured using Schneider’s technique. The change in working length was assessed using repeated-measures ANCOVA. The direct visualization measurements were statistically larger than the electronic measurements (paired t-test difference = 0.20 mm, SE = 0.037, P < .0001), although a difference this large may not be clinically important. Overall, a greater change in working length was observed in straight canals than in curved canals. This unexpected finding was attributed to the limitations of the study, specifically the confounding factor of root length. This trend was more pronounced when measured electronically than via direct visualization, especially after complete instrumentation than after coronal flaring. The overall change in working length after complete instrumentation was found to be clinically insignificant in this study. A limited amount of change in working length may be expected prior to obturation.

Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2009.

Oil extraction in Nigeria has caused extensive environmental degradation and health problems in many Nigerian communities, particularly in the ecologically sensitive Niger Delta where nearly all of the oil extraction takes place. The reasons for this are complex and have roots in Nigeria’s colonial past. The Nigerian economy is largely reliant on its petroleum resources which, in conjunction with governmental corruption and high international demand for Nigerian oil, has created a system where environmental externalities are largely ignored. Multinational oil companies with little stake in the development and environment of Nigeria are responsible for most of the extraction projects and subsequent environmental damage. However, the Nigerian federal government has failed to effectively regulate these projects. Communities in the Niger Delta bear nearly all of the environmental burden of oil extraction, but see very little of the economic benefits. The main environmental impacts of oil extraction are oil spills, land use change, and gas flaring. Oil spills are very common in the Niger Delta. Cleanup efforts are often inadequate, resulting in loss of delicate ecosystems as well as fisheries and farmland. Large tracts of rainforest and mangrove ecosystems have been cleared or degraded by the oil extraction process. Nigeria flares more gas per barrel of oil extracted than any other country in the world, contributing to global warming and creating serious health hazards for communities located near gas flares. Diversification of the Nigerian economy would help to alleviate many of the factors that lead to environmental degradation, including the dependence of the government on oil revenues, high unemployment, and rampant oil theft. Curbing government corruption is also vital to effective regulation of oil extraction. International consumers can help Nigeria head towards a less petroleum-driven future through an increased awareness of the origins of their oil and pressure on the Nigerian federal government and the multinational oil companies to extract oil more conscientiously or even to discontinue oil extraction. But most importantly, the solution to Nigeria’s economic concerns must ultimately come from Nigerians as international influence has been a major contributor to the environmental degradation in the first place.

Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2009.

Thesis (M.Ing. (Development and Management))--North-West University, Potchefstroom Campus, 2009.

Through the Global Gas Flaring Reduction (GGFR) initiative a substantial amount of effort and international attention has been focused on the reduction of gas flaring since 2002 (Elvidge et al., 2009). Nigeria is rated as the second country in the world for gas flaring, after Russia. In an attempt to reduce and eliminate gas flaring the federal government of Nigeria has implemented a number of gas flaring reduction projects, but poor governmental regulatory policies have been mostly unsuccessful in phasing it out. This study examines the effects of pollution from gas flaring using multiple satellite based sensors (Landsat 5 TM and Landsat 7 ETM+) with a focus on vegetation health in the Niger Delta. Over 131 flaring sites in all 9 states (Abia, Akwa Ibom, Bayelsa, Cross Rivers, Delta, Edo, Imo, Ondo and Rivers) of the Niger Delta region have been identified, out of which 11 sites in Rivers State were examined using a case study approach. Land Surface Temperature data were derived using a novel procedure drawing in visible band information to mask out clouds and identify appropriate emissivity values for different land cover types. In 2503 out of 3001 Landsat subscenes analysed, Land Surface Temperature was elevated by at least 1 ℃ within 450 m of the flare. The results from fieldwork, carried out at the Eleme Refinery II Petroleum Company and Onne Flow Station, are compared to the Landsat 5 TM and Landsat 7 ETM+ data. Results indicate that Landsat data can detect gas flares and their associated pollution on vegetation health with acceptable accuracy for both Land Surface Temperature (range: 0.120 to 1.907 K) and Normalized Differential Vegetation Index (sd ± 0.004). Available environmental factors such as size of facility, height of stack, and time were considered. Finally, the assessment of the impact of pollution on a time series analysis (1984 to 2013) of vegetation health shows a decrease in NDVI annually within 120 m from the flare and that the spatio-temporal variability of NDVI for each site is influenced by local factors. This research demonstrated that only 5 % of the variability in δLST and only 12 % of the variability in δNDVI, with distance from the flare stack, could be accounted for by the available variables considered in this study. This suggests that other missing factors (the gas flaring volume and vegetation speciation) play a significant role in the variability in δLST and δNDVI respectively.

The Diploma thesis describes the implementation of innovative production of protective liner to the manufacturing company. The liner is manufactured in sizes of nominal diameter DN 200 - DN 500. The material is low-alloy steel EN 10216-2 10CrMo9-10. For the production innovation, the technology of pipe end flaring by a movable mandrel was chosen. Verification of the functionality of this technology was performed using analytical calculations and numerical simulation of FEM. The results of numerical methods were compared with the results of a practical experiment. The experiment was performed on 5 test specimens with a diameter of 273 mm. The machine device was a hydraulic press with a nominal force of 2000 kN and equipped with pressure and position sensors. The experimentally obtained values of force and the tool path dependence were similar with the values of FEM simulation. The difference in the value of the force in the maximum tool path was 290 kN. The flared diameter was formed to a value of 319 mm. This value corresponds to 16.5% of increased nominal diameter, which is sufficient from design point of view. Non-destructive tests ruled out the presence of crack defects on the flared diameter. According the new set up working procedure was produced the first real part. Significant financial savings of CZK 3.5 - 5.3 million / year were quantified in the technical and economic evaluation. Return on necessary investments is between the 9th - 14th manufactured pieces (approx. 15% of the annual production volume). In conclusion, innovation has promising results and will be issued by the company into the production process.

Master s thesis is focused on flaring of tubes endings. There are also mentioned theoretical pieces of knowledge which relate to tubes endings by a flat edge and a cone. The following experiments performed with the own material and tools made by the author s design. Experiments in the production of the flat collar led to the speedy rotation of the sample ending. Experiments with the conical ending brought valuable results from the point of view of comparison of theoretical and measured powers, distribution of thicknesses and utilization of the deformation web to set voltage-deformation state. The dimension excent of the conical ending was limited by the formation of buckling in the cylindrical part of the tube.

The thesis builds on the project FSI-S-14-2394, in which the biaxial state of tension of longitudinally welded tubes made from material 17 240 was investigated. The experiment was carried out under dynamic conditions on an impact tester, which was designed with structural simplicity and ease of observation of the experiment in mind. Deformation was recorded by high-speed cameras and a dynamometer. Results of the experiment were processed by measuring devices and subsequently used in a simulation created using a software utilizing the finite element method. Simulations were created for samples DA8 and DB9. These samples were selected because they did not crack and were fully stamped. Results of the simulation correspond to the values measured by high-speed cameras and a dynamometer with a small variance. Based on comparison of the results, it can be states that the simulation is technically acceptable.