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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

An Investigation of the Malaysian Palm Oil Industry’s Environmental Strategies, Stakeholders’ Pressure, Environmental Effectiveness and Competitive Advantage

Yaacob, Mohd Rafi January 2007 (has links)
Research Doctorate - Doctor of Philosphy (PhD) / Over the last three decades there has been increasing pressure from stakeholders on businesses to be environmentally responsible. Business organisations cannot help but take this consideration seriously because it has a far-reaching impact on their very survival. This research is intended to bring insights into how and why a business’s management responds to environmental pressure from stakeholders. How a business responds to its stakeholders is known as environmental strategy. In addition, this study also investigates how proactiveness in implementation of each type of environmental strategy impacts on a business’s environmental effectiveness and competitive advantage. In Malaysia palm oil is the most important agricultural commodity in the country, and contributes substantially to the economy. Unfortunately, its activities are not without environmental costs. Deforestation, depletion of flora and fauna, excessive use of chemicals, air and water pollution are the results of the industry’s activity. But due to stakeholders’ pressures, the industry has embraced environmental management in its activities, albeit at a slow pace. Against this background, this study seeks to investigate the efficacy of corporate environmentalism, using a number of palm oil companies as case studies. This study is paramount as no such study has previously been conducted in Malaysia. The Malaysian palm oil industry offers an interesting case for studying corporate environmentalism in developing countries. Using a mixed-methods or triangulation of analysis of nine palm oil companies, which are listed on the Kuala Lumpur Stock Exchange, as case studies, this research investigates the environmental practices of the palm oil companies, and the relationship of these practices with stakeholders’ pressures, environmental effectiveness and competitive advantages. The results of the study reveal that three levels of overall environmental strategy are adopted by the participating palm oil companies. They are labelled by the researcher as minimalists - four companies; intermediators - two companies; and proactivists - three companies. The minimalists refer to companies that exercised the lowest environmental strategy, while the proactivists are those who exercised the highest environmental strategy. The intermediators are in the middle, that is, those companies that seem to be in the early stage of becoming proactivists, but have yet to achieve such a level. The proactivists were classified as those who exercised a proactive strategy, but both intermediators and minimalists exercised a reactive environmental strategy. In terms of the relationship between environmental proactiveness and stakeholders’ pressure it was found that the management of the more proactive companies tended to perceive a wider range of threats from environmental stakeholders compared with reactive companies. Apart from regulatory stakeholders, they also perceived pressure from primary stakeholders, especially their top management, as well as secondary stakeholders including ENGOs, competitors, and the media. On the contrary, reactive companies only perceived threats from regulatory stakeholders. Not only did proactivists differ in terms of stakeholders’ pressure, they were at the same time perceived to be more environmentally effective and to gain more competitive advantages than less proactive companies. Based on the research findings it seems there is a significant positive correlation between a proactive environmental strategy and both environmental effectiveness and competitive advantage among Malaysian palm oil companies. In this study measurement of the environmental strategies and environmental effectiveness was solely based on a triangulation of surveys (seven-point scale items) and in-depth interviews. In order to increase the validity of the study, future researchers need to triangulate these data with other quantitative data. For instance, at a company level, a company’s resources can be measured based on its financial statistics such as sales, net profit, return on investment, and the amount spend on research and development. Moreover, the environmental effectiveness of a mill can be measured in terms of monthly data of biochemical oxygen demand (BOD), of palm oil mill effluents and Ringelmann Chart of air emissions, and the amount of money expended on de-sludging for certain periods of time. In both plantations and mills, future researchers can gather data related to environmental accidents, fines and court cases. The key findings of this research are instructive. The majority of the participating palm oil companies in Malaysia adopted reactive environmental strategies. Only a few adopted proactive environmental strategies, and they were more likely to exercise environmental practices at strategic and tactical levels such as top management involvement in environmental issues as well as deploying environmental management systems which mostly related to the bottom line of their businesses. Serious attention towards the destruction of the tropical rainforest as a result of their activities is lacking among participating companies.
42

The Feasibility study of using Palm oil as the lubricant of Automative Engine

tzeng, jason 19 August 2001 (has links)
In general,the lubricants were composed by basestock and additive,and the basestock is usual use mineral oil. This paper examines the viscosity,viscosity index and antiwear properties of palm oil blended lubricants. To study the feasibility of using palm oil as the lubricant of automative engine . The V.I. of commercial sae 30 engine oil will increase from 101 to 147 via the blend of palm oil and SAE 30.The anti-wear charactisteristics test in a four-ball tribometer.Under conditions of 40kg,1200rpm,and a test duration of one hour at 120 ¢J. The test oil appear markedly superior to the reference SAE 30 engine oil .The palm oil blended lubricant showed is reduced to 10% scar than reference oil .
43

Women and palm oil processing in Sierra Leone: a case study.

Conteh, Juliana Konima, Carleton University. Dissertation. Geography. January 1992 (has links)
Thesis (M.A.)--Carleton University, 1992. / Also available in electronic format on the Internet.
44

Determinação do nível de dano econômico para opsiphanes invirae Hübner, 1808 (Lepidoptera:Nymphalidae) em palma de óleo /

Tinôco, Ricardo Salles. January 2016 (has links)
Orientador: Odair Aparecido Fernandes / Coorientador: LeonG. Higley / Banca: Paulo Roberto Silva Farias / Banca: Ivan Carlos Fernandes Martins / Banca: Walkymário de Paulo Lemos / Banca: Alessandra de Jesus Boari / Resumo: O óleo de palma destaca-se por ser a principal fonte alimentícia de óleo vegetal liderando a produção mundial seguido da soja. Devido à escassez de estudos básicos para manejo de desfolhadores em palma de óleo, este trabalho objetivou avaliar a resposta fisiológica das plantas sob desfolha e efeito da desfolha na produção, bem como determinar o nível de dano econômico. Esse trabalho mostrou que a injúria artificial com tesoura e natural por lagartas de B. sophorae não resultou em efeitos no processo fisiológico das folhas remanescentes em mudas de híbrido interespecífico (Elaeis guineensis Jacq. X Elaeis oleifera [Kunth, Cortés]) e, provavelmente, as plantas responderam com mecanismos compensatórios evitando assim interromper seus processos fisiológicos evitando a perda de água, mantendo seu processo autotrófico nos tecidos remanescentes. Os resultados mostraram ainda que a desfolha ocasionada pelas lagartas e a mecânica não apresentaram diferenças e que injúrias mecânicas podem ser usadas em estudos de desfolha simulada. Com isso, justificou-se o uso de desfolha artificial para estudar seu efeito sobre a produção. Paralelamente, obteve-se o consumo de área foliar total para larvas de Opsiphanes invirae Hübner, que foi de 286,064 cm2. O nível de dano econômico foi 5,14 e 2,98 lagartas por folha utilizando o produto Dipel® WP e SC, respectivamente para dados de perdas acumuladas em dois anos. Considerando apenas a injúria artificial obtida nas condições da Ag... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Palm oil is notable for being the main food source of vegetable oil leading the world production followed by soybeans. Due to the shortage of basic studies for management of palm oil defoliators, this study aimed to evaluate the physiological response of plants under defoliation and effect of defoliation on the production, as well as to determine economic injury level. This work showed that the artificial injury using scissors and natural using B. sophorae larvae did not result in effects to the physiological process of the remaining leaves in interspecific hybrid seedlings (Elaeis guineensis Jacq. X Elaeis oleifera [Kunth, Cortés]) and, probably, the plants responded with compensatory mechanisms avoiding interruption of the physiological processes preventing the loss of water, keeping the autotrophic process in the remaining tissues. The results also showed that the defoliation either caused by the larvae or by scissors did not show differences and mechanical injuries can be used in simulated defoliation studies. Thus, this justified the use of artificial defoliation to study its effect on production. At the same time, the consumption of total leaf area was obtained for Opsiphanes invirae Hübner larvae, which was 286.064 cm2 and the level of economic damage to this species in oil palm. The economic injury level was 5.14 and 2.98 larvae per leaf using the product Dipel® WP and SC, respectively, using two-year loss data. Considering only the artificial injury ... (Complete abstract click electronic access below) / Doutor
45

Desenvolvimento e avaliacao da incorporacao e liberacao de oleo de acai em hidrogeis de poli(N-vinil-2-pirrolidona / Açaí oil development and evaluation of immobilization and release in poly (N-vinyl-pyrrolidone) hydrogels

MACHADO, ANA C.H.R. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:57Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:55Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
46

Improved modulation of the endogenous antioxidant system and inflammatory responses in male wistar rats by rooibos (Aspalathus linearis) and red palm oil (Elaeis guineensis)

Ajuwon, Olawale Razaq January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the degree Doctor of Technology: Biomedical Technology In the Faculty of Health and Wellness Sciences At the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / Oxidative stress and chronic (low-grade) inflammation are inseparably interconnected and both have been implicated in the aetiology of many disease states. The use of plant extracts for disease prevention and therapeutic purposes, is gaining more attention because of the health benefits of the bioactive phytochemicals in these extracts. This thesis reports on the antioxidant status, the oxidative stress modulation and anti-inflammatory properties of fermented rooibos (Aspalathus linearis) and red palm oil (RPO) from the oil palm plant (Elaeis guineensis) using a long-term and two short-term in vivo models. In the first (long-term) study, the effect of chronic feeding of rooibos, RPO or their combination on the endogenous antioxidant system was investigated. Data from this study provided:  The first scientific evidence that chronic feeding of rooibos, RPO or their combination for 22 weeks did not adversely affect the liver or kidney function parameters.  The first scientific evidence that chronic feeding of rooibos alone, or together with RPO for 22 weeks modulated the endogenous antioxidant system by inhibiting MDA formation and augmenting the reduced glutathione status.  The first scientific evidence of an additive or synergistic interaction in the ability of rooibos and RPO to modulate the endogenous antioxidant system. The second (short-term) study investigated the protective effects of rooibos, RPO or their combination on tert-butyl hydroperoxide (t-BHP)-induced oxidative hepatotoxicity, and results from this study provided:  The first evidence of the ability of the two extracts, either alone or in combination to protect against t-BHP induced hepatotoxicity. Supplementation of rooibos, RPO or their combination for eight weeks reversed the hepatic damage induced by t-BHP. The changes induced by t-BHP in the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GR) were reversed by these plant extracts. The extracts, supplemented alone or combined prevented lipid peroxidation as shown by the decreased levels of conjugated dienes iv (CD) and malondialdehyde (MDA) and reversed the t-BHP.-induced impairment of the glutathione redox status. The third (short-term) study provided the first scientific evidence of the in vivo anti-inflammatory properties of rooibos and RPO. The properties were demonstrated using a lipopolysaccharide (LPS)-induced hepatic endotoxemic model by:  Providing the first evidence of an additive or synergistic interaction in the ability of the combined rooibos extract and RPO supplementation to reverse LPS-induced hepatic damage.  Providing the first evidence for the modulation of the inflammatory responses by rooibos extract, RPO or their combination. Supplementation of rooibos extract, RPO or their combination for four weeks, modulated LPS-induced inflammatory responses by inhibiting the synthesis of pro-inflammatory cytokines, tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6).  Providing evidence that the observed anti-inflammatory effects of rooibos and RPO may be related to their ability to modulate oxidative stress. Supplementation of rooibos extract, RPO or their combination for four weeks, prevented hepatic lipid peroxidation induced by LPS by decreasing CD and MDA formation in the liver. Changes induced in the activities of antioxidant enzymes were reversed and the glutathione redox status was augmented. Based on these study results, it is proposed that the ability of rooibos and RPO to protect the liver, modulate endogenous antioxidant system and inhibit inflammatory responses may be associated with the unique combination of antioxidant phytochemicals in both plant extracts. The study suggested possible mechanism(s) for the observed health effects, and the development of rooibos and RPO as nutraceuticals, which may be beneficial in the prophylactic management of oxidant-induced liver injury.
47

Influence of two plant products (red palm oil and rooibos) on streptozotocin-induced hyperglycaemia and its implications on antioxidant status and other biochemical parameters in an animal model

Ayeleso, Ademola Olabode January 2012 (has links)
Thesis submitted in fulfilment of the requirements for the Doctor of Technology: Biomedical Technology In the Faculty of Health and Wellness At the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / Diabetes mellitus is a major health problem not only in urban, but also in the rural areas and is diagnosed by the presence of high glucose levels in the blood. Oxidative stress is known to be actively involved in the onset and progression of diabetes and its complications. Antioxidants have important roles in biological systems by scavenging free radicals which may result in oxidative damage of biological molecules such as lipids, proteins and DNA. Red palm oil, originally from the tropical area of Africa, generally consumed as cooking oil, is known to have some beneficial health effects due to the presence of lipid soluble antioxidants such as carotenoids, tocopherols and tocotrienols. It also contains almost an equal proportion of both saturated and unsaturated fatty acids which makes it distinctive from other vegetable oils. Rooibos, on the other hand, is grown in the Cederberg area of the Western Cape in South Africa and it is commonly consumed as a beverage. It contains a complex profile of water soluble antioxidants (flavonoids) and its health promoting potentials have been reported extensively. Some of the flavonoids present in rooibos include aspalathin, nothofagin, quercetin, rutin and orientin. The objective of this research project was to examine the potential beneficial effects of the dietary intake of red palm oil and rooibos on streptozotocin-induced hyperglycaemia and its influence on the antioxidant status and some biochemical parameters in male Wistar rats. The preliminary phase of this study was designed to investigate the biochemical effects of these two plant products at different dosages following consumption for a period of 7 weeks. The preliminary study did not reveal any adverse effects of the different dosages of red palm oil (1 ml, 2 ml and 4 ml) and rooibos (2%, 4% and 6%) on the experimental rats following dietary intake for 7 weeks. However, these natural products showed an improvement in the antioxidant status of the rats at the different doses. Using a single dose each of both plant products from the preliminary study, the main study was performed to investigate the influence of these two plant products singly and in combination on the blood and liver of streptozotocin-induced hyperglycaemic male Wistar rats. In the main study, streptozotocin (50 mg/kg) dissolved in 0.1 M citrate buffer (pH 4.5) through intramuscular injection was used for the induction of diabetes which was confirmed by the presence of high blood glucose after 72 hours. Red palm oil or rooibos extract alone did not have any effect on the control of blood glucose in the diabetic rats. The dietary intake of the combined treatment with red palm and rooibos had more health promoting effects on the diabetic rats which included a decrease in blood glucose, glycosylated haemoglobin, fructosamine and increased insulin levels. There was a marked increase in liver glycogen levels in all the diabetic groups. Treatment with rooibos alone showed a decrease in glycogen levels in the diabetic rats. The presence of liver enzymes in the serum, commonly used as indicators of liver damage was increased in all the diabetic rats. However, the combined treatment of diabetic rats with red palm oil and rooibos protected the liver from injury. Red palm oil improved high density lipoprotein cholesterol levels (HDL-cholesterol) in the diabetic rats. There was no effect on the activity of glucokinase, the first enzyme in the the glycolytic pathway in both the untreated and treated diabetic rats. However, the activity of pyruvate kinase, the last enzyme in the glycolytic pathway was reduced in all the diabetic groups. The combined treatment with both red palm and rooibos increased the activity of pyruvate kinase. Oxidative stress was confirmed in the diabetic rats with an increase in the plasma thiobarbituric acid reactive substances (TBARS), an indicator of lipid peroxidation. Treatment of diabetic rats with rooibos and the combination of red palm oil and rooibos brought plasma TBARS to a level that was not significantly different from the normal control group. There was a non-significant reduction of total glutathione in the non-treated and treated diabetic groups. A non-significant increase in the activity of liver catalase was observed in all the treated diabetic groups. The activity of superoxide dismutase was significantly decreased in the liver of diabetic rats. Diabetic rats treated with red palm oil, rooibos and the combined treatment showed an increased activity of superoxide dismutase in the liver. Red palm oil and the combined treatment increased the activity of glutathione peroxidase in both the red blood cells and liver of diabetic rats. Red palm oil, rooibos and their combined treatments also improved the plasma antioxidant capacity such as ferric reducing antioxidant power (FRAP) and oxygen reducing absorbance capacity (ORAC) in the diabetic rats. In conclusion, oxidative stress is actively involved in the progression of diabetes mellitus. Red palm oil and rooibos, most especially their combined treatment showed significant beneficial health promoting effects in the diabetic rats. The remarkable effects of the combined treatment of red palm oil and rooibos in the diabetic rats could be due to their antioxidant profiles. Based on the findings from this study, it can be adduced that these plant products could help in the management of diabetes and its complications and therefore, suggested the need for further research studies on antioxidant therapy in the management of diabetes mellitus.
48

Effects of red palm oil-supplementation on oxidative stress biomarkers in an experimental rat model

Alinde, Olatogni Berenice Lidwine January 2012 (has links)
Thesis (MTech (Biomedical Technology))--Cape Peninsula University of Technology, 2012. / Oxidative stress, in recent times appears to be a major underlying risk factor in the occurrence of various diseases such as cardiovascular disease (CVD) and ischemic heart disease (IHD). During oxidative stress, there is an imbalance between the production of reactive oxygen species (ROS) and antioxidant defence mechanisms in favour of ROS. This results in severe cellular damages in the heart, vascular membranes and other organs. Potential benefits of dietary supplements as one of the major quenching elements against oxidative stress have been highlighted. Thus, a growing interest has been stimulated in finding natural alternatives for the treatment and! or prevention of oxidative stress-mediated diseases. Red palm oil (RPO), refined from the tropical plant Elaeis guineensis was used in this study since it has captivated much attention in the health sector lately. The effects of RPO-supplementation on oxidative stress biomarkers as well as homocysteine, a cardiovascular disease risk factor in an oxidative stress-induced rat model were investigated in this in vivo study. All experiments were conducted for a period of six weeks. Male Wistar rats (120-150g) were randomly divided into six groups (n=5) where all the rats received a standard diet. Two groups (groups C, D) were supplemented with 0.175g RPO (7g RPO/kg chow) for four weeks whereas groups (groups E, F) were given 0.175g RPO (7g RPO/kg chow) supplementation for six weeks. Rats in control groups (groups A, B) were not given any RPO-supplementation. Groups B, 0, F were induced with oxidative stress by injection of 0.5ml (20IlM/100g of body weight) organic tertiary-butyl hydroperoxide. All parameters were determined using appropriate methods in plasma, serum and erythrocytes. Data were expressed as mean ± SEM. No significant differences were obtained between groups for total antioxidant capacity and glutathione peroxidase activity. Red palm oil supplementation significantly increased superoxide dismutase activity after 6 weeks consumption, total glutathione levels after 4 weeks consumption and homocysteine levels after four and six weeks consumption in rats not subjected to oxidative stress. Under oxidative stress conditions, malondialdehyde (MOA) level, a marker of oxidative stress related damage, significantly increased in rats receiving a standard diet. However, when RPO diet was supplemented for 4 and 6 weeks, MOA levels significantly decreased towards the value of normal controls. In conclusion, our findings suggest that RPO-supplementation could ameliorate antioxidant status in the body through its potential ability to increase some antioxidant enzymes activity. Similarly, it is suggested that RPO-supplementation could protect the rat against oxidative stress induced damage in diseased state.
49

Produção de biodiesel a partir da alcoólise do óleo de palma / The production of biodiesel from the alcoholysis of palm oil

André Luiz Ferreira Matassoli 28 November 2008 (has links)
No presente trabalho foi investigada a produção de biodiesel a partir da alcoólise do óleo de palma catalisada por lipase imobilizada comercial. O efeito da razão molar de álcool:óleo, da forma de adição do álcool (única e escalonada), da temperatura de reação, da concentração de enzima, do tipo de álcool (metanol e etanol), do tipo de enzima e da reutilização da enzima no rendimento final de reação foi avaliado. As reações conduzidas com etanol apresentaram rendimentos superiores aos obtidos com o emprego de metanol devido à maior desativação da lipase pelo álcool de menor número de átomos de carbono. O maior rendimento em biodiesel (54%) foi obtido empregando razão molar de álcool:óleo de 3:1, com adição escalonada de etanol (0, 30 e 60 minutos), 9% (m/m) de Lipozyme TL IM a 50C. Não foi possível recuperar a lipase ao final das reações, pois a matriz de imobilização se solubilizou no meio. Além disso, para comparação, foi investigada a utilização das lipases comerciais imobilizadas Lipozyme RM IM e Novozym 435 e dos catalisadores químicos KOH, MgO e La2O3. O rendimento em biodiesel nas reações catalisadas pelas lipases foi maior do que os obtidos com catalisadores químicos. A menor eficiência dos catalisadores químicos pode ser justificada pelo alto índice de acidez do óleo de palma (6,26 mg KOH.g-1) que promove o consumo do catalisador (KOH), devido à neutralização dos ácidos graxos livres presentes no óleo, e o bloqueio dos sítios ativos dos catalisadores químicos sólidos devido à adsorção dos ácidos graxos nestes sítios / The production of biodiesel from the alcoholysis of palm oil catalyzed by commercial immobilized lipase was investigated. The effect of alcohol:oil molar ratio, addition of alcohol (single and stepwise), reaction temperature, concentration of enzyme, type of alcohol (ethanol and methanol), type of enzyme, and reuse of enzyme on reaction yield was evaluated. The reactions carried out using ethanol showed yields higher than those obtained when methanol was used. This behavior is related to the deactivation of lipase caused by an alcohol with small number of carbon atoms. The highest yield on biodiesel (54%) was obtained using an alcohol:oil molar ratio of 3:1, with stepwise addition of ethanol (0, 30 and 60 minutes), 9 wt.% of Lipozyme TL IM at 50C. The recovery of lipase was not possible at the end of the reaction, because the lipase support has solubilized in the reaction medium. In addition, for comparison, the use of commercial immobilized lipase Lipozyme RM IM and Novozymes 435 and of chemical catalysts KOH, MgO, and La2O3 have been investigated. The yield on biodiesel using lipases as catalysts was higher than those obtained using chemical catalysts. The lower efficiency of chemical catalysts can be justified by the high acidity of palm oil (6,26 mg KOH.g-1) which promotes the consumption of the catalyst (KOH), due to the neutralization of free fatty acids in the oil, and the blockage of the active sites of solid chemical catalysts by adsorption of fatty acids on these sites
50

Simulation, design and analysis of economic feasibility of palm oil biodiesel production by unsing heterogeneous catalytic transesterification route / SimulaÃÃo, projeto e anÃlise de viabilidade econÃmica da produÃÃo de biodiesel de Ãleo de dendà em rota de transesterificaÃÃo catalÃtica heterogÃnea

Caio Braga de Sousa 23 February 2015 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Uma unidade de produÃÃo contÃnua de biodiesel com carga de 8000 kg.h-1 de Ãleo de dendà e metanol, com o uso da rota de transesterificaÃÃo heterogÃnea foi simulada, projetada e analisada economicamente com o uso do software Aspen HYSYS 7.3 e de planilhas de cÃlculo. O pacote termodinÃmico NRTL foi empregado para representar as propriedades de todos os fluidos na simulaÃÃo. Reatores de leito fixo foram dimensionados utilizando simulaÃÃes numÃricas para atingirem 97,3% de conversÃo do Ãleo no processo. Os reatores foram operados isotermicamente a 64,8ÂC e com razÃo Ãlcool/Ãleo de 17,5. Uma coluna de destilaÃÃo foi projetada para recuperar 99% do metanol em excesso. Um decantador para separar as fases biodiesel e glicerina foi dimensionado atravÃs do cÃlculo do tempo de residÃncia t. Uma segunda coluna de destilaÃÃo a vÃcuo foi projetada para purificar a fase biodiesel atà atingir 99,97% m/m, de acordo com as especificaÃÃes da ANP. A fase glicerina foi purificada em uma coluna de destilaÃÃo flash a vÃcuo atà 99,53% m/m. O Investimento Total ITOTAL da unidade foi estimado pelo MÃtodo Fatorial Detalhado, resultando em um valor de US$ 5,798,469. Os Custos VariÃveis de ProduÃÃo (VCOP) foram estimados utilizando a precificaÃÃo de matÃrias primas, de catalisador e utilidades, enquanto que as receitas anuais foram calculadas com uso das precificaÃÃes do biodiesel e da glicerina. Os Custos Fixos de ProduÃÃo (FCOP) foram orÃados considerando os custos com mÃo de obra operacional, custos de supervisÃo, custos de manutenÃÃo e reparos, despesas corporativas e seguro. Para o cÃlculo do fluxo de caixa do projeto foi considerado o regime tributÃrio vigente no Brasil, com a inclusÃo do PIS/COFINS a uma taxa segundo a regra geral e a reduÃÃo de 69% deste para empresas que adquiram o selo social, uma taxa de 12% para o ICMS incididos sobre as receitas, 25% de IRPJ e 9% de CSLL incididos sobre o Lucro LÃquido antes do Imposto de Renda (LAIR). Foi obtido um Lucro LÃquido apÃs Impostos (LL) de US$ 2,340,889, valor este positivo em comparaÃÃo com processos convencionais que utilizam Ãleo de soja virgem. A viabilidade econÃmica do projeto foi analisada pelo cÃlculo do Valor Presente LÃquido (VPL) e pela Taxa Interna de Retorno (TIR). Foram obtidos um VPL de US$ 21.36 milhÃes de dÃlares e TIR de 39,0%, valores que demonstraram a viabilidade econÃmica do projeto. A anÃlise de sensibilidade de preÃos de matÃrias primas demonstrou tambÃm que o processo à viÃvel desde que os preÃos do Ãleo dendà nÃo aumentem ou os do biodiesel nÃo diminuam, ambos em 3%. / A continuous biodiesel production plant with an 8000 kg.h-1 inlet of palm oil and methanol, using the heterogeneous transesterification route was simulated, designed and economically assessed with the software Aspen HYSYS 7.3 and spreadsheets. The thermodynamic fluid package NRTL was selected in order to represent all properties of the fluids through the simulation. Packed-bed reactors were designed using numerical simulation to achieve an oil conversion of 97.3% in the process. The reactors were operated isothermally at 64.8ÂC and with an alcohol/oil ratio of 17.5. A vacuum distillation column was designed to recovery 99% of the methanol in excess. A decanter to separate the biodiesel and glycerin phases was designed through the calculation of residence time t. A second vacuum distillation column was designed to purify the biodiesel phase until a 99.97 wt%, in accordance with the ANP specifications. The glycerin phase was purified in a vacuum flash distillation column until a 99.53 wt%. The Total Capital Invested ITOTAL on the plant was estimated using the Detailed Factorial Method presenting the amount of US$ 5,798,469 was found. The Variable Costs of Production (VCOP) were estimated using the prices of raw materials, catalysts and utilities, whereas the annual revenues were calculated using the prices of biodiesel and glycerin. The Fixed Costs of Production (FCOP) were calculated using the operating labor costs, supervision, maintenance, corporate overheads and insurance. In order to calculate the cash flow of the project, the current tax regime in Brazil was used, including PIS/COFINS with a rate following the general rule and the reduction of 69% on it to companies with the social stamp, 25% of IRPJ and 9% of CSLL on the Net Profit before Income Taxes (NPIT). A Net Profit after Taxes (NP) of US$ 2,340,889 was obtained, a positive figure if compared to conventional processes using virgin soybean oil. The economic viability of the project was analyzed by calculating the Net Present Value (NVP) and Internal Rate of Return (IRR). A NVP of US $ 21.36 million and IRR of 39.0% were obtained, showing the economic viability of the project. The raw material price sensitivity analysis also showed that the process is feasible as long as palm oil prices do not increase or biodiesel do not decrease more than 3%.

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