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Canada has large reserves of heavy oil stored in the form of oil sands in the Athabasca region. This type of heavy oil does not flow at room temperature and its agglomeration with sand complicates its extraction. Consequently, extraction of the oil is costly and remains challenging. This project aims to use a temperature-responsive polymeric surfactant (TRPS) to improve the extraction of oil. The temperature-responsive polymeric surfactant (TRPS) poly(ethylene glycol)-b-poly[2-(2-methoxyethoxy) ethyl methacrylate] (PEG-b-PMEO2MA) was successfully prepared by atom transfer radical polymerization (ATRP) and its efficacy at extracting oil from oil sands was investigated. First, several PEG-b-PMEO2MA samples were synthesized having an absolute molecular weight ranging from 17,000 to 20,000 g/mol as determined by NMR and an apparent PDI ranging from 1.1 to 1.5 as determined by GPC analysis. Then, the lower critical solution temperature (LCST) was found to equal 34 ?? 1??C for all samples by turbidity measurements. The PEG113-b-PMEO2MA64 micelles in aqueous solution, whose hydrodynamic diameter (dh) determined by dynamic light scattering (DLS) equaled 26.3 ?? 0.3 nm, had an aggregation number (Nagg) of 100 ?? 8. After characterization of this TRPS, PEG-b-PMEO2MA was used for oil extraction and showed promising results. With the addition of 60 to 65 mg of toluene on top of 15 mL of a 1 mg/mL PEG-b-PMEO2MA aqueous solution, complete oil recovery could be achieved by putting the TRPS solution with 1 g of oil sands in a shaker at 45 or 50 ??C for 24 hrs. In addition, a time-dependent oil extraction experiment showed that by using a 1 mg/mL TRPS aqueous solution, 100% oil recovery was reached after only 6 hrs. Furthermore, the PEG-b-PMEO2MA aqueous solution could be recycled for several oil extraction cycles while still maintaining a high oil recovery.

Colombia is the worst country to be a trade unionist in the world. Approximately 3,000 workers have been assassinated in the last 30 years, the state, paramilitary organizations and some multinationals being responsible for most of the murders. This fact highlights the importance of researching the mechanisms of mass violence against trade unionists including the mechanisms on part of the trade unionists that keep trade unionism alive. Because of the importance of studying power and resistance as part of social change, this thesis presents an ethnography of political violence against the labourers and the trade unionists that work for Pacific Rubiales Energy in the department of Meta, with focus on how those trade unionists resist such violence with an open resistance to both political violence and coercive capital accumulation. I state that the trade unionists, by adapting their list of demands to the locals' social and environmental needs, overstep corporatist trade unionism allowing them to break the social and physical death imposed by the state, the mafias and the multinational. I argue that the trade unionists' open resistance not only allows them to continue their social struggle and to challenge the violence exerted against them, but permits them to modernize a country that sustains a semi-feudal structure beneficial for the multinationals, the mafia barons and the economic and political elites by challenging their corrupt and murderous relations.

No description available.

Since the price of fossil fuel has increased, petroleum resources have been restricted and the environmental effects have been of great concern. Biofuel has been considered to be a good solution because it is a clean, non-pollutant and a renewable energy. Biodiesel is one alternative energy that plays a major role in the energy industry. So, the development of biofuel process is more interesting. Jatropha curcas L. is considered as an alternative energy source in order to help solve the energy crisis. The purpose of this research is to investigate the optimum condition of Jatropha seed extraction via a screw press and its by-product utilization by a pyrolysis method for achieving the maximum mass conversion and energy recovery. In this study, Jatropha seeds were first extracted by a screw press with different discharge aperture sizes, namely, number 4 (4.0 mm), 8 (7.0 mm), and 10 (10.5 mm). The by-product obtained from a screw press was then performed pyrolysis runs at the operating temperatures of 400, 500, and 600 degrees C. Results revealed that the optimum condition was achieved when using discharge aperture number 8 (7.0 mm) for a screw press and performing the pyrolysis of the by- product at 500 degrees C. The mass conversion efficiency of 35.8% refined oil, 21.8% bio-char, 14.6% bio-oil, and 11.7% syn-gas were obtained. Therefore, the utilization of by-product using a pyrolysis can enhance the effectiveness of Jatropha oil extraction with only 16% mass losses occurred. In addition, the gross heating values of the products were observed as 39.6 MJ/kg for the refined oil, 35.1 MJ/kg for the bio-oil, 27.5 MJ/kg for the bio-char, and 2.1 MJ/kg for the syn-gas. Due to a high mass conversion efficiency and energy content of Jatropha products, Jatropha has the potential to serve as an alternative energy source.

Os modelos atuais de produção de biodiesel contam com a fábrica de biodiesel independente da fábrica de extração de óleo, causando desgaste logístico e falhas no sistema que, para não sucumbir, atrela matérias-primas desfavoráveis à produção, encarecendo o produto final, e perdendo competitividade no mercado com o combustível diesel. Para o trabalho foi montado um equipamento de extração que funcionou também na produção do biodiesel. Com a extração do óleo com etanol é possível conseguir uma miscela, que resfriada à temperatura ambiente, produz uma fase oleosa, capaz de gerar ésteres etílicos com rendimento bastante favorável. Para a produção do biodiesel o álcool utilizado foi o etanol, que por apresentar certa miscibilidade com o óleo, favorece a reação à temperatura ambiente. Ao final, foi utilizada a glicerina na fase de separação dos ésteres em lugar da destilação a vácuo, atingindo 92% de rendimento em massa, e um biodiesel de qualidade. Esse trabalho demonstrou a viabilidade técnica e produtiva de sistemas de extração e biodiesel conjugados, com menor demanda de energia, e a perspectiva de aproximar também a destilaria de etanol formando um complexo mais estabilizado e econômico / The present models of biodiesel production is based on biodiesel plants regardless of the oil extraction industry location, causing many logistic problems and fails on the system, which in order not to go unactive, adopts unusual fat sources, raising the costs of the final product, and losing market competitiveness to diesel fuel. In this paper, we developed an extraction equipment that can be also used for the production of the biodiesel. Resulting from the oil extraction with ethanol it is possible produce a miscelle that cooled to ambient temperatures generate an oily phase, able to yield ethyl esters efficiently. In order to produce biodiesel ethanol was the alcohol used, that due to a certain miscibility with the oil, favored the reaction at ambient temperature. At the end, the glycerin was used, instead of vacuum distillation, in the esters separation, with a 92% of mass efficiency, and a quality biodiesel. This work demonstrated the technical and product viability of conjugated extraction and esterification systems with lower energy requirement, and the perspective to be close to the ethanol distillery becoming a more stable and economical complex

Os modelos atuais de produção de biodiesel contam com a fábrica de biodiesel independente da fábrica de extração de óleo, causando desgaste logístico e falhas no sistema que, para não sucumbir, atrela matérias-primas desfavoráveis à produção, encarecendo o produto final, e perdendo competitividade no mercado com o combustível diesel. Para o trabalho foi montado um equipamento de extração que funcionou também na produção do biodiesel. Com a extração do óleo com etanol é possível conseguir uma miscela, que resfriada à temperatura ambiente, produz uma fase oleosa, capaz de gerar ésteres etílicos com rendimento bastante favorável. Para a produção do biodiesel o álcool utilizado foi o etanol, que por apresentar certa miscibilidade com o óleo, favorece a reação à temperatura ambiente. Ao final, foi utilizada a glicerina na fase de separação dos ésteres em lugar da destilação a vácuo, atingindo 92% de rendimento em massa, e um biodiesel de qualidade. Esse trabalho demonstrou a viabilidade técnica e produtiva de sistemas de extração e biodiesel conjugados, com menor demanda de energia, e a perspectiva de aproximar também a destilaria de etanol formando um complexo mais estabilizado e econômico / The present models of biodiesel production is based on biodiesel plants regardless of the oil extraction industry location, causing many logistic problems and fails on the system, which in order not to go unactive, adopts unusual fat sources, raising the costs of the final product, and losing market competitiveness to diesel fuel. In this paper, we developed an extraction equipment that can be also used for the production of the biodiesel. Resulting from the oil extraction with ethanol it is possible produce a miscelle that cooled to ambient temperatures generate an oily phase, able to yield ethyl esters efficiently. In order to produce biodiesel ethanol was the alcohol used, that due to a certain miscibility with the oil, favored the reaction at ambient temperature. At the end, the glycerin was used, instead of vacuum distillation, in the esters separation, with a 92% of mass efficiency, and a quality biodiesel. This work demonstrated the technical and product viability of conjugated extraction and esterification systems with lower energy requirement, and the perspective to be close to the ethanol distillery becoming a more stable and economical complex

No description available.

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.

Growing energy demand in the world force people to investigate alternative energy sources. Unlike coal or other fossil fuels, renewable energy sources are promising for the future. Especially, seed oils are effectively used as energy sources such as fuel for diesel engines. The scope of this study is to develop an oil extraction machine specific to canola seed. In this study, seed oil extraction methods have been investigated and various alternatives for the extraction machine have been considered. For continuous operation, oil extraction with a screw press is evaluated as the most appropriate solution. Four different prototypes have been designed and manufactured. According to the results of testing of prototypes, they have been modified and gradually improved to increase oil extraction efficiency. The working principle of the selected screw press based on the rotation of a tapered screw shaft mounted inside a grooved vessel. The screw shaft is a single square-threaded power screw having an increasing root diameter from inlet to exit while the outside diameter of the screw shaft is 66 mm. Seeds are taken into the system at the point where the depth of the screw thread is maximum. Then they are pushed forward by the threads on the rotating screw shaft and pass through inside the vessel. So, the fed seeds are compressed as they move to the other side of the vessel. Recovered oil escapes from high pressure zone and drains back. The oil is drained out from the oil drainage holes that are machined on high pressure zone of the vessel. Besides, the cake is extruded at the end of the vessel and the screw shaft. The cake thickness is adjustable by the axial movement of the screw shaft. By adjusting the cake thickness, different pressures can be obtained. During the experiments, it is observed that four main features affect the oil recovery rate. These are the geometry of the grooves inside the vessel, the taper angle of the screw shaft, the operating temperature and the rotational speed. With the final prototype, an oil recovery efficiency of 62.5% has been achieved at 40 rpm with 15 kg/h seed capacity. Since the oil content of the seed is taken as 40%, oil recovery rate of the developed oil extraction machine is 3.75 kg/h. This efficiency is determined for a 0.8 mm cake thickness at 1.1 kW motor ower.