Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-13T20:38:54Z No. of bitstreams: 1 RafaelaDiniz.pdf: 3023880 bytes, checksum: b1ca6eabaf77f0f2a4d741dea14a11ba (MD5) / Made available in DSpace on 2017-06-13T20:38:54Z (GMT). No. of bitstreams: 1 RafaelaDiniz.pdf: 3023880 bytes, checksum: b1ca6eabaf77f0f2a4d741dea14a11ba (MD5) Previous issue date: 2011-10-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The industry of I refinery of petroleum it is a great degrading of the environment, becayse she has potential of affect him in all the levels: air, water, soil and, consequently, the health of the you be alive. With the implantation of this enterprise, certainly the environmental quality of the resources and the health of the population of the municipal districts of the surroundings of the Refinery they will be affected direct and or indirectly. This research had as objective of the close municipal districts to the enterprise. A total 300 interviews was accomplished between the months of August and October of 2010, in the municipal districts of Bacabeira, Santa Rita and Rosário and in the rural places of the municipal district of São Luís: Estiva, Coqueiro and Vila Maranhão. For the collection of the data questionnaries were used semi-structured that were developed randomly with the population of the municipal districts and rural places involved in the research, the obtained data were stored in a database of the Program Excel 2007 so that they could be systematized and tabulated. The results demonstrated that in 62,0% of the interviewees in Santa Rita, 76% in Rosário, 40% in Vila Maranhão, they found the situation of the terrible health. The main diseases observed during the study they were the diseases of waterborne, and 34% of the intervewees in Coqueiro, 28% in Rosário, 52% in Santa Rita and 36% in Vila Maranhão, they already contracted primness. The form used for the "waste disposal" more found in the homes it was the septic sewage, 40% in Bacabeira, 42% in Coqueiro, 48% in Rosário , 50% in Santa Rita and 44% in Vila Maranhão. Most of the population doesn't know where the garbage is discarded, 46% in Bacabeira, 32% in Rosário, 42% in Santa Rita and 42% in Vila Maranhão. Most of the interviewees doesn't make any treatment type in the water, being naturally more exposed to the diseases. In relation to the perception of the interviewees' environment 81,3% they affirm that the environmental education is important, in relation to the climatic changes, 95,3% of the interviewees observed alterations in relation to the thermal sensation. Fifty-four percent of respondents in Bacabeira, 58% Coqueiro 74% in Rosario, in Santa Rita 60% and 70% in Vila Maranhão said that environmental degradation is worsening. The levels of pollutant stayed inside of the stablished patterns in the Resolução CONAMA nº03/90, not altering of this sorts out the quality of the air of the municipal districts. It is fundamental that are elaborated and made possible programs and monitoring politics and increment of the health and of the environmental resources, so that the operation of this enterprise doesn't swallow serious risks to the local resources and the health of the involved population. / A indústria de refino de petróleo é uma grande degradadora do ambiente, pois tem potencial para afetá-lo em todos os níveis: ar, água, solo e, conseqüentemente, a saúde dos seres vivos. Com a implantação deste empreendimento, certamente a qualidade ambiental dos recursos e a saúde da população dos municípios do entorno da Refinaria serão afetados direta e ou indiretamente. Esta pesquisa teve como objetivo avaliar a qualidade ambiental e diagnosticar a situação da saúde da população dos municípios próximos ao empreendimento. A metodologia usada consistiu em um total de 300 entrevistas realizadas entre os meses de agosto e outubro de 2010, nos municípios de Bacabeira, Santa Rita e Rosário e nas localidades rurais do município de São Luís: Estiva, Coqueiro e Vila Maranhão. Para a coleta dos dados foram utilizados questionários semi- estruturados que foram desenvolvidos aleatoriamente com a população dos municípios e localidades rurais envolvidas na pesquisa, os dados obtidos foram armazenados em um banco de dados do Programa Excel 2007 para que pudessem ser sistematizados e tabulados. Os resultados demonstraram que em 62,0% dos entrevistados em Santa Rita, 76% em Rosário, 40% em Estiva e 40% em Vila Maranhão, acharam a situação da saúde péssima. As principais doenças observadas durante o estudo foram as doenças de veiculação hídrica, sendo que 34% dos entrevistados em Coqueiro, 28% em Rosário, 52% em Santa Rita e 36% em Vila Maranhão, já contraíram dengue. A forma usada para o “descarte de dejetos” mais encontrado nos domicílios foi a fossa séptica, 40% em Bacabeira, 42% em Coqueiro, 48% em Rosário, 50% em Santa Rita e 44% em Vila Maranhão. A maior parte da população (46% em Bacabeira, 32% em Rosário, 42% em Santa Rita e 42% em Vila Maranhão) não sabe onde o lixo é descartado. A maioria dos entrevistados não faz qualquer tipo de tratamento na água, estando naturalmente mais expostos às doenças. Em relação à percepção do ambiente, 81,3% dos entrevistados afirmam que a educação ambiental é importante. Em relação às mudanças climáticas, 95,3% dos entrevistados observaram alterações em relação à sensação térmica. Cinqüenta e quatro por cento dos entrevistados em Bacabeira, 58% em Coqueiro, 74% em Rosário, 60% em Santa Rita e 70% em Vila Maranhão afirmaram que a degradação do ambiente está piorando. Os níveis de poluentes permaneceram dentro dos padrões estabelecidos pela Resolução CONAMA Nº03/90, não alterando desta maneira a qualidade do ar dos municípios. É fundamental que sejam elaboradas e viabilizadas programas e políticas de monitoramento e incremento da saúde e dos recursos ambientais, para que a operação deste empreendimento não traga sérios riscos aos recursos locais e à saúde da população envolvida.

Nowadays, computers are extensively used in engineering modeling and simulation fields in many different ways, one of which is in chemical engineering. Simulation and modeling of a chemical process plant and the sizing of the equipment with the assistance of computers, is of special interests to process engineers and investors. This is due to the ability of high speed computers, which make millions of mathematical calculations in less than a second associated with the new powerful software that make the engineering calculations more reliable and precise by making very fast iterations in thermodynamics, heat and mass transfer calculations. This combination of new technological hardware and developed software enables process engineers to deal with simulation, design, optimization, control, analysis etc. of complex plants, e.g. refinery and petrochemical plants, reliably and satisfactorily. The main chemical process simulators used for static and dynamic simulations are ASPEN PLUS, ASPEN HYSYS, PRO II, and CHEMCAD. The basic design concepts of all simulators are the same and one can fairly use all simulators if one is expert in any of them. Hydrogenation process is an example of the complex plants, to which a special attention is made by process designers and manufacturers. This process is used for upgrading of hydrocarbon feeds containing sulfur, nitrogen and/or other unsaturated hydrocarbon compounds. In oil and gas refineries, the product of steam cracking cuts, which is valuable, may be contaminated by these unwanted components and thus there is a need to remove those pollutants in downstream of the process. Hydrogenation is also used to increase the octane number of gasoline and gas oil. Sulfur, nitrogen and oxygen compounds and other unsaturated hydrocarbons are undesired components causing environmental issues, production of by-products, poisoning the catalysts and corrosion of the equipment. The unsaturated C=C double bonds in dioleffinic and alkenyl aromatics compounds, on the other hand, cause unwanted polymerization reactions due to having the functionality equal to or greater than 2. Hydrogenation process of the undesired components will remove those impurities and/or increase the octane number of aforementioned hydrocarbons. This process is sometimes referred to as “hydrotreating”; however, “upgrader” is a general word and is, of course, of more interest. In this thesis, a hydrogenation process plant was designed on the basis of the chemistry of hydrocarbons, hydrogenation reaction mechanism, detailed study of thermodynamics and kinetics and then a steady-state simulation and design of the process is carried out by ASPEN HYSYS 2006 followed by design evaluation and some modifications and conclusions. Hydrogenation reaction has a complicated mechanism. It has been subjected to hot and controversial debates over decades. Many kinetic data are available, which contradict one another. Among them, some of the experimental researches utilize good assumptions in order to simplify the mechanism so that a “Kinetic Reaction” modeling can be employed. This thesis takes the benefit of such research works and applies some conditions to approve the validity of those assumptions. On the basis of this detailed study of reaction modeling and kinetic data, a hydrogenation plant was designed to produce and purify over 98 million kilograms of different products; e.g. Benzene, Toluene, Iso-octane etc. with fairly high purity.

Nowadays, computers are extensively used in engineering modeling and simulation fields in many different ways, one of which is in chemical engineering. Simulation and modeling of a chemical process plant and the sizing of the equipment with the assistance of computers, is of special interests to process engineers and investors. This is due to the ability of high speed computers, which make millions of mathematical calculations in less than a second associated with the new powerful software that make the engineering calculations more reliable and precise by making very fast iterations in thermodynamics, heat and mass transfer calculations. This combination of new technological hardware and developed software enables process engineers to deal with simulation, design, optimization, control, analysis etc. of complex plants, e.g. refinery and petrochemical plants, reliably and satisfactorily. The main chemical process simulators used for static and dynamic simulations are ASPEN PLUS, ASPEN HYSYS, PRO II, and CHEMCAD. The basic design concepts of all simulators are the same and one can fairly use all simulators if one is expert in any of them. Hydrogenation process is an example of the complex plants, to which a special attention is made by process designers and manufacturers. This process is used for upgrading of hydrocarbon feeds containing sulfur, nitrogen and/or other unsaturated hydrocarbon compounds. In oil and gas refineries, the product of steam cracking cuts, which is valuable, may be contaminated by these unwanted components and thus there is a need to remove those pollutants in downstream of the process. Hydrogenation is also used to increase the octane number of gasoline and gas oil. Sulfur, nitrogen and oxygen compounds and other unsaturated hydrocarbons are undesired components causing environmental issues, production of by-products, poisoning the catalysts and corrosion of the equipment. The unsaturated C=C double bonds in dioleffinic and alkenyl aromatics compounds, on the other hand, cause unwanted polymerization reactions due to having the functionality equal to or greater than 2. Hydrogenation process of the undesired components will remove those impurities and/or increase the octane number of aforementioned hydrocarbons. This process is sometimes referred to as “hydrotreating”; however, “upgrader” is a general word and is, of course, of more interest. In this thesis, a hydrogenation process plant was designed on the basis of the chemistry of hydrocarbons, hydrogenation reaction mechanism, detailed study of thermodynamics and kinetics and then a steady-state simulation and design of the process is carried out by ASPEN HYSYS 2006 followed by design evaluation and some modifications and conclusions. Hydrogenation reaction has a complicated mechanism. It has been subjected to hot and controversial debates over decades. Many kinetic data are available, which contradict one another. Among them, some of the experimental researches utilize good assumptions in order to simplify the mechanism so that a “Kinetic Reaction” modeling can be employed. This thesis takes the benefit of such research works and applies some conditions to approve the validity of those assumptions. On the basis of this detailed study of reaction modeling and kinetic data, a hydrogenation plant was designed to produce and purify over 98 million kilograms of different products; e.g. Benzene, Toluene, Iso-octane etc. with fairly high purity.

In recent years, ¡§Boost the economy and cut down the unemployment rate¡¨ has become a common understanding of the people in Taiwan, which is the government¡¦s goal for economic development as well. One of the most effective strategies to boost the economy is to encourage investment. However, the rising concern of environmental protection and the consciousness of living peacefully with the mother natural have become a trend nowadays. Furthermore, not only business but also the government and the neighboring residents have increased their standards for environmental protection. Therefore, the industry has tended to be more prudent to any new development project. What deserves to be mentioned is, no matter how wonderful a proposed project is, without the support of local residents, no project can be executed. Therefore, we should regard the citizen participation and environmental impact assessment (EIA). China Petroleum Corporation (CPC) proposed at the end of 2002, aiming to make the transformation from an oil plant to a hi-tech petrochemical zone on Kaohsiung Oil Refinery, with new petrochemical equipment and nono-technology. Ministry of Economic Affairs has agreed with the proposed transformation with the condition that CPC has to obtain approval from the local residents, representatives and government. According to the analysis of power interaction, this study intends to provide related policy suggestions to the government and CPC with the purpose of economic prosperity. For the evolution of modern society, sustainable development and business continuity will play important roles. Besides adopting opinion poll, Delphi Technique is also applied as the research methodology to carry on experts¡¦ interviews and questionnaires investigation.

In view of the current situation of fluctuating high crude oil prices, it is now more important than ever for petroleum refineries to operate at an optimal level in the present dynamic global economy. Acknowledging the shortcomings of deterministic models, this work proposes a hybrid of stochastic programming formulations for an optimal midterm refinery planning that addresses three factors of uncertainties, namely price of crude oil and saleable products, product demand, and production yields. An explicit stochastic programming technique is utilized by employing compensating slack variables to account for violations of constraints in order to increase model tractability. Four approaches are considered to ensure both solution and model robustness: (1) the Markowitz???s mean???variance (MV) model to handle randomness in the objective coefficients of prices by minimizing variance of the expected value of the random coefficients; (2) the two-stage stochastic programming with fixed recourse approach via scenario analysis to model randomness in the right-hand side and left-hand side coefficients by minimizing the expected recourse penalty costs due to constraints??? violations; (3) incorporation of the MV model within the framework developed in Approach 2 to minimize both the expectation and variance of the recourse costs; and (4) reformulation of the model in Approach 3 by adopting mean-absolute deviation (MAD) as the risk metric imposed by the recourse costs for a novel application to the petroleum refining industry. A representative numerical example is illustrated with the resulting outcome of higher net profits and increased robustness in solutions proposed by the stochastic models.

Aims and objectives: The research aims and objectives of this thesis were: (i) to review literature pertaining to different dermal exposure assessment methods; (ii) to assess dermal exposure of refinery workers to nickel and/or cobalt by making use of skin wipes as a removal method; (iii) to assess concurrently the skin condition of the above mentioned workers by measuring skin hydration, transepidermal water loss (TEWL) and skin surface pH, and (iv) to compare South African skin notations and sensitisation notations with those of other developed countries. Methods: Refinery workers from two base metal refineries participated in this study. Skin condition and dermal exposure was measured on different anatomical areas before, during and at the end of a work shift. Dermal exposure to nickel and/or cobalt was assessed with Ghostwipes TM as a removal method. Wipe samples of potentially contaminated surfaces in the workplace were also collected. Wipes were analysed for nickel and/or cobalt according to NIOSH method 9102, using Inductively Coupled Plasma-Atomic Emission Spectrometry. The assignment and use of skin notations and sensitisation notations in South African legislation and six other developed countries were compared. Results: To date, occupational dermal exposure has been reported for numerous substances by making use of surrogate skin methods (interception methods), removal methods and fluorescent tracer methods (in situ detection methods). From published literature it is evident that skin (dermal) wipes, as a removal method, are the most appropriate method to assess dermal exposure to metals. Varying degrees of skin dryness (low hydration indices) and impaired barrier function (high TEWL indices) are reported, with the hands being implicated the most. However, normal skin condition is also reported for some anatomical areas. Skin surface pH for all anatomical areas sampled decreased significantly during the shift, but remained in normal range. Dermal exposure to nickel occurred during the shift at the electro-winning plant of one refinery, while dermal co-exposure to cobalt and nickel occurred at the cobalt plant of the other refinery. At both of the refineries, cobalt and/or nickel was collected from the workers’ skin even before the shift. Also, dermal exposure to these metals was highly variable between individual workers. Skin notations in South African legislation had a mean agreement of between 42.9% and 45.8% with other countries, while agreement for sensitisation notations was only 3.6% between countries. / Thesis (Ph.D. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2011.

Background: Platinum refinery workers are exposed to various elements during the refining process, with soluble platinum salts posing a potential health risk. Platinum salts are extremely potent sensitisers that can result in the clinical syndrome of platinum salt sensitivity (PSS) that leads to skin and respiratory hypersensitivity in refinery workers. Several published research articles document refinery workers’ exposure levels to soluble platinum salts during production. However, the exposure levels to soluble platinum salts during non–routine stock take activities are unknown although cases of sensitisation have been diagnosed following these nonoperational periods. Stock take for the platinum refinery under study commenced on 18 January 2010 and ended 22 February 2010. Increased emphasis was placed on flushing plant equipment rather than dismantling it. The aim was to dismantle 10% of what previously was dismantled to reduce the risk of exposing employees to soluble platinum salts, to reduce the chance of damaging plant equipment and for cost and time saving purposes. Aim: The objectives of this study are to: (i) quantify work area and personal exposure levels; (ii) identify work areas and work practices with exposure levels exceeding the occupational exposure limit (OEL) (>2 ug/m3); (iii) determine whether exposure levels differ significantly between: a) personal sampling groups (engineering versus production), b) area sampling groups (open versus closed–face sampling), c) work areas, d) total area and total personal sampling groups and to (iv) evaluate the efficiency of the current control measures utilised. Design and Method: A total of 58 platinum samples were collected, consisting of 38 personal and 20 area samples. Personal sampling consisted of Institute of Occupational Medicine (IOM) samplers housing reusable 25 mm filter cassettes with mixed cellulose ester (MCE) membrane filters for the collection of inhalable airborne particles. Because both the cassette and the filter were pre and post–weighed as a single unit, all particles collected (even those against the walls of the cassette) were included in the analysis. Sampling was conducted in accordance with the stock take schedule and scope and included a roster for the systematic dismantling and cleaning of the refinery, following the process flow. A target population of maximum five fitters and five operators per area were identified, responsible for dismantling and cleaning plant equipment respectively. The sampling strategy was based on the identification and sampling of employees presumed to have the highest exposure risk. The Occupational Exposure Sampling Strategy Manual (OESSM) refers to this as the “maximum risk employees” (Liedel et al., 1977). The selection of the maximum risk employees was done with reasonable certainty since the employees sampled were working closest to the source of exposure. Sampling was conducted for the total duration of the task consisting of single sample measurements. Area sampling was conducted by means of BUCKAir high volume samplers fitted with preweighed 47 mm MCE filter cassettes to show the spread of the contaminant in the work area. The high volume samplers were calibrated to operate at a sampling volume of 20 L/min. The sampling heads were positioned 1.5 m from the ground surface and as near as possible to the work location or failing this as near as is possible to major sources of exposure. Samples were collected and analysed according to the method for the determination of hazardous substances 46/2 (MDHS 46/2). This is an advanced sampling and analysis standard which enables detection of low levels of soluble platinum (0.01 ug/m3). Results: Thirty eight personal platinum samples were collected, consisting of a sampled engineering (n=15) and production (n=23) subgroup. Out of the thirty eight personal samples taken in total, 21% of the samples’ concentrations exceeded the OEL of 2 ug/m3 and ranged between 0.004–20.479 ug/m3. Twenty area platinum samples were collected, consisting of open (n=10) and closed face (n=10) sampling. Out of the twenty area samples taken in total, 10% of the samples’ concentrations exceeded the OEL of 2 ug/m3 and ranged between 0.0004–5.752 ug/m3. The mean personal exposure levels for the production subgroup (2.739 ug/m3) were significantly higher compared to the engineering subgroup’s mean personal exposure levels (0.393 ug/m3). This significant difference (p=0.033) was expected since the production subgroup was more exposed and involved in the digging out of residues and the cleaning of plant equipment compared to the engineering subgroup with limited exposure and involved in the opening of plant equipment. Although the mean exposure levels for open face sampling (0.725 ug/m3) were higher compared to the mean exposure levels for closed face sampling (0.441 ug/m3) no significant difference (p=0.579) were noted. The mean area exposure levels (0.583 ug/m3) were significantly lower (p=0.004) compared to the mean personal exposure levels (1.813 ug/m3) for similar areas and tasks performed and, therefore, not an effective indicator of personal exposure levels. Higher personal exposure levels were expected since the workers were closer to the source of exposure and since the platinum salts could have diluted in the workplace’s air resulting in lower area exposure levels. Conclusion: The research study addressed the problem statement, met the objectives set out in Chapter 1, hypotheses were accepted and rejected and future studies were recommended. It was hypothesised that: a) refinery workers are exposed to airborne soluble platinum during non–operational periods; b) exposure levels do not differ significantly between the personal sampling groups (engineering vs production); c) exposure levels do not differ significantly between the area sampling groups (open versus closed–face sampling); d) exposure levels do not differ significantly between work areas; e) exposure levels differ significantly between total personal and total area sampling groups. The results confirmed that refinery workers are exposed to airborne soluble platinum during non–operational periods and hypothesis a was accepted. The personal exposure levels of the engineering versus production sampling groups differed statistically (p=0.033) and hypothesis b was rejected. The exposure levels of the open and closed face sampling groups did not differ significantly (p=0.579) and hypothesis c was accepted. In addition no statistical difference (p>0.05) was indicated between the work areas and hypothesis d was accepted. Total personal versus total area exposure levels (p=0.004) differed statistically and hypothesis e was accepted. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2011.

Aims and objectives: The research aims and objectives of this thesis were: (i) to review literature pertaining to different dermal exposure assessment methods; (ii) to assess dermal exposure of refinery workers to nickel and/or cobalt by making use of skin wipes as a removal method; (iii) to assess concurrently the skin condition of the above mentioned workers by measuring skin hydration, transepidermal water loss (TEWL) and skin surface pH, and (iv) to compare South African skin notations and sensitisation notations with those of other developed countries. Methods: Refinery workers from two base metal refineries participated in this study. Skin condition and dermal exposure was measured on different anatomical areas before, during and at the end of a work shift. Dermal exposure to nickel and/or cobalt was assessed with Ghostwipes TM as a removal method. Wipe samples of potentially contaminated surfaces in the workplace were also collected. Wipes were analysed for nickel and/or cobalt according to NIOSH method 9102, using Inductively Coupled Plasma-Atomic Emission Spectrometry. The assignment and use of skin notations and sensitisation notations in South African legislation and six other developed countries were compared. Results: To date, occupational dermal exposure has been reported for numerous substances by making use of surrogate skin methods (interception methods), removal methods and fluorescent tracer methods (in situ detection methods). From published literature it is evident that skin (dermal) wipes, as a removal method, are the most appropriate method to assess dermal exposure to metals. Varying degrees of skin dryness (low hydration indices) and impaired barrier function (high TEWL indices) are reported, with the hands being implicated the most. However, normal skin condition is also reported for some anatomical areas. Skin surface pH for all anatomical areas sampled decreased significantly during the shift, but remained in normal range. Dermal exposure to nickel occurred during the shift at the electro-winning plant of one refinery, while dermal co-exposure to cobalt and nickel occurred at the cobalt plant of the other refinery. At both of the refineries, cobalt and/or nickel was collected from the workers’ skin even before the shift. Also, dermal exposure to these metals was highly variable between individual workers. Skin notations in South African legislation had a mean agreement of between 42.9% and 45.8% with other countries, while agreement for sensitisation notations was only 3.6% between countries. / Thesis (Ph.D. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2011.

Background: Platinum refinery workers are exposed to various elements during the refining process, with soluble platinum salts posing a potential health risk. Platinum salts are extremely potent sensitisers that can result in the clinical syndrome of platinum salt sensitivity (PSS) that leads to skin and respiratory hypersensitivity in refinery workers. Several published research articles document refinery workers’ exposure levels to soluble platinum salts during production. However, the exposure levels to soluble platinum salts during non–routine stock take activities are unknown although cases of sensitisation have been diagnosed following these nonoperational periods. Stock take for the platinum refinery under study commenced on 18 January 2010 and ended 22 February 2010. Increased emphasis was placed on flushing plant equipment rather than dismantling it. The aim was to dismantle 10% of what previously was dismantled to reduce the risk of exposing employees to soluble platinum salts, to reduce the chance of damaging plant equipment and for cost and time saving purposes. Aim: The objectives of this study are to: (i) quantify work area and personal exposure levels; (ii) identify work areas and work practices with exposure levels exceeding the occupational exposure limit (OEL) (>2 ug/m3); (iii) determine whether exposure levels differ significantly between: a) personal sampling groups (engineering versus production), b) area sampling groups (open versus closed–face sampling), c) work areas, d) total area and total personal sampling groups and to (iv) evaluate the efficiency of the current control measures utilised. Design and Method: A total of 58 platinum samples were collected, consisting of 38 personal and 20 area samples. Personal sampling consisted of Institute of Occupational Medicine (IOM) samplers housing reusable 25 mm filter cassettes with mixed cellulose ester (MCE) membrane filters for the collection of inhalable airborne particles. Because both the cassette and the filter were pre and post–weighed as a single unit, all particles collected (even those against the walls of the cassette) were included in the analysis. Sampling was conducted in accordance with the stock take schedule and scope and included a roster for the systematic dismantling and cleaning of the refinery, following the process flow. A target population of maximum five fitters and five operators per area were identified, responsible for dismantling and cleaning plant equipment respectively. The sampling strategy was based on the identification and sampling of employees presumed to have the highest exposure risk. The Occupational Exposure Sampling Strategy Manual (OESSM) refers to this as the “maximum risk employees” (Liedel et al., 1977). The selection of the maximum risk employees was done with reasonable certainty since the employees sampled were working closest to the source of exposure. Sampling was conducted for the total duration of the task consisting of single sample measurements. Area sampling was conducted by means of BUCKAir high volume samplers fitted with preweighed 47 mm MCE filter cassettes to show the spread of the contaminant in the work area. The high volume samplers were calibrated to operate at a sampling volume of 20 L/min. The sampling heads were positioned 1.5 m from the ground surface and as near as possible to the work location or failing this as near as is possible to major sources of exposure. Samples were collected and analysed according to the method for the determination of hazardous substances 46/2 (MDHS 46/2). This is an advanced sampling and analysis standard which enables detection of low levels of soluble platinum (0.01 ug/m3). Results: Thirty eight personal platinum samples were collected, consisting of a sampled engineering (n=15) and production (n=23) subgroup. Out of the thirty eight personal samples taken in total, 21% of the samples’ concentrations exceeded the OEL of 2 ug/m3 and ranged between 0.004–20.479 ug/m3. Twenty area platinum samples were collected, consisting of open (n=10) and closed face (n=10) sampling. Out of the twenty area samples taken in total, 10% of the samples’ concentrations exceeded the OEL of 2 ug/m3 and ranged between 0.0004–5.752 ug/m3. The mean personal exposure levels for the production subgroup (2.739 ug/m3) were significantly higher compared to the engineering subgroup’s mean personal exposure levels (0.393 ug/m3). This significant difference (p=0.033) was expected since the production subgroup was more exposed and involved in the digging out of residues and the cleaning of plant equipment compared to the engineering subgroup with limited exposure and involved in the opening of plant equipment. Although the mean exposure levels for open face sampling (0.725 ug/m3) were higher compared to the mean exposure levels for closed face sampling (0.441 ug/m3) no significant difference (p=0.579) were noted. The mean area exposure levels (0.583 ug/m3) were significantly lower (p=0.004) compared to the mean personal exposure levels (1.813 ug/m3) for similar areas and tasks performed and, therefore, not an effective indicator of personal exposure levels. Higher personal exposure levels were expected since the workers were closer to the source of exposure and since the platinum salts could have diluted in the workplace’s air resulting in lower area exposure levels. Conclusion: The research study addressed the problem statement, met the objectives set out in Chapter 1, hypotheses were accepted and rejected and future studies were recommended. It was hypothesised that: a) refinery workers are exposed to airborne soluble platinum during non–operational periods; b) exposure levels do not differ significantly between the personal sampling groups (engineering vs production); c) exposure levels do not differ significantly between the area sampling groups (open versus closed–face sampling); d) exposure levels do not differ significantly between work areas; e) exposure levels differ significantly between total personal and total area sampling groups. The results confirmed that refinery workers are exposed to airborne soluble platinum during non–operational periods and hypothesis a was accepted. The personal exposure levels of the engineering versus production sampling groups differed statistically (p=0.033) and hypothesis b was rejected. The exposure levels of the open and closed face sampling groups did not differ significantly (p=0.579) and hypothesis c was accepted. In addition no statistical difference (p>0.05) was indicated between the work areas and hypothesis d was accepted. Total personal versus total area exposure levels (p=0.004) differed statistically and hypothesis e was accepted. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2011.

[pt] Em consequência da atuação das empresas de petróleo em um mercado globalizado, uma das etapas do processo de internacionalização destas empresas é a aquisição de refinarias em novos mercados. Destacam-se aqueles em que as oportunidades são mais desafiadoras, como as emergentes economias do Oriente, principalmente a China e a Índia. Se a eficiência de um sistema logístico é crítica para as operações das empresas em seus próprios países, torna-se ainda mais importante para estas operações globalizadas, considerando-se os diferentes ambientes encontrados nos países onde as empresas passam a operar. A tomada de decisão sobre a aquisição de novas refinarias fora de seus países requer o conhecimento dos impactos desta aquisição sobre os fluxos de petróleo e seus produtos entre os mercados, considerando-se os diferentes fatores que atuam sobre estes fluxos. Neste trabalho, por meio de uma pesquisa bibliográfica, estuda-se a proposta da Petrobras em desenvolver uma ferramenta de avaliação do fluxo de petróleo e seus produtos em função da compra de novas refinarias, a ser utilizada no processo de tomada de decisão. Estudam-se as principais variáveis críticas de projeto a serem consideradas no futuro desenvolvimento dessa ferramenta. / [en] As a consequence of the performance of the oil companies in a globalized market, one of the steps of the internationalization process of these companies is the acquisition of refineries in new markets. Among them are those where opportunities are more challenging, as the emerging economies of the East, especially China and India. If the efficiency of a logistics system is critical to the companies operations in their countries, it becomes even more important for these globalized operations, considering different environments of the countries where the companies will operate. The decision on the acquisition of new refineries out of their countries requires the knowledge of the impact of that acquisition on the oil and its products flow through the markets, considering the various different factors that affect them. Based on a literature survey, in this work the proposal for developing a tool for evaluating the oil and its products flow for Petrobras as a function of the purchase of new refineries that will be used in the decision making process is studied. This thesis analyses the main project s critical variables to be considered in the future development of this tool.