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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.
71

Synthesis of cross-linked pine cone biosorbent and its applications in industrial wastewater treatment

Kupeta, Albert Jerry Kafushe 11 1900 (has links)
M. Tech. (Department of Chemistry, Faculty of Applied and Computer Sciences) -- Vaal University of Technology / The widespread use of phenols and phenolic derivatives in industrial applications has resulted in their discharge as part of industrial wastewater. These chemicals are toxic and need to be removed from the aqueous environment. Amongst the available pollutant removal technologies, adsorption has been widely used due to its simplicity, ease of operation, cost-effectiveness and ability to sequester pollutants at very low concentrations. Different adsorbents have been applied for removal of phenols and their derivatives. Use of agricultural waste as adsorbents seems to offer a much cheaper alternative in pollutant removal. This study examines the synthesis of a hydrophobic biomaterial composite by cross-linking of Fenton treated pine cone and applying the prepared adsorbent for 2-nitrophenol removal from aqueous solution. Pine cone biomass, in its raw and modified forms was tested for its ability to remove 2-nitrophenol from simulated industrial wastewater. The experimental procedure is divided into two main parts: (1) pine cone modification using Fenton’s reagent and 1.6-hexamethylene diisocyanate and (2) application of the prepared hydrophobic adsorbent for 2-nitrophenol removal from wastewater. Fenton’s reagent was used to remove pigments, extractives and other soluble organic compounds from the raw pine. FTIR spectroscopy showed an increase in magnitude of oxygenated surface groups which resulted in a decrease in pHpzc. The effect of Fenton treatment on further modification of the pine biomass via cross-linking using 1.6-hexamethylene diisocyanate was investigated. Optimum reaction variables for the cross-linking using dibutyltin dilaurate as catalyst under an inert nitrogen gas atmosphere in anhydrous hexane solvent were determined using FTIR spectroscopy. Success of the cross-linking procedure was confirmed by use of analytical techniques (XRD, TGA, SEM, EDX and BET surface area) and weight percent gain calculations. Pine and modified pine biomass were tested for their ability to sequester 2-nitrophenol via batch adsorption technique. The effect of pine modification on affinity for the biosorbate was investigated. The mechanism of the adsorption process was determined via use of kinetic, diffusion and equilibrium isotherm models. Two error functions (coefficient of determination and percent variable error) were employed to substantiate the model showing a good fit to the experimental adsorption data. The experimental adsorption kinetic data was fit to the pseudo-first-order and pseudo-second-order kinetic models. Due to the large size of the pollutant molecules diffusion process analysis was also conducted. The effect of pine modification on kinetic and diffusion parameters was determined. The experimental equilibrium adsorption data was fit to the Freundlich, Redlich-Peterson and Hill isotherm models. The initial shapes of the adsorption isotherms for 2-nitrophenol adsorption onto pine and modified pine biomass determined the type of equilibrium isotherm models to fit the experimental data to. Thermodynamic parameters were calculated to determine the spontaneity, feasibility and energy changes associated with the adsorption process. The degree of disorder at the solid/liquid interface after the adsorption was determined. The effect of temperature on the adsorption process was used to show whether the adsorption is physical or chemical. The effect of pine modification on equilibrium isotherm parameters was determined. The study is divided into seven chapters: Chapter 1: The chapter covers the introduction, problem statement, aim and objectives of the research. It gives an insight into the research project. Chapter 2: The literature review of pollutants in industrial wastewater and methods of their removal is dealt with in this chapter. Adsorption is introduced as an alternative technique for pollutant removal from aqueous systems. An in-depth review of various adsorbents (including pine cone), their merits and limitations are also discussed together with methods of modifying and use of modified adsorbents. Equilibrium, kinetic and thermodynamic models used to treat adsorption experimental data are presented. Chapter 3: The experimental procedures on the synthesis, characterization and application of the hydrophobic biosorbent in the removal of 2-nitrophenol from aqueous solution are presented. Kinetic and equilibrium experiments are described in detail. Chapter 4: It describes the first part of the results and discussions. The chapter focuses on optimization of reaction variables and characterization (using various analytical techniques) of the hydrophobic biomaterial composite. Chapter 5 The chapter discusses the second part of the results. It focuses on magnitude of surface charge, pHpzc and kinetic studies. Fitting of the adsorption experimental data to kinetic and diffusion models is presented together with the error functions. Chapter 6 The chapter discusses part three of the results on equilibrium studies. The adsorption experimental data is fitted to equilibrium isotherm equations and error determination is presented. Thermodynamic parameters are calculated and interpreted. Chapter 7: Conclusion and recommendations are presented. The optimum reaction variables for cross-linking of Raw and Fenton treated pine cone were determined using FTIR analysis and found to be: 0.2 g pine biomass, 3.5 cm3 1.6-hexamethylene diisocyanate cross-linker, 50 cm3 anhydrous hexane solvent, 1.5 cm3 dibutyltin dilaurate catalyst, temperature of 50 °C and a reaction time of 4 hours. The pine surface showed an increase in phenolic, lactonic and carboxylic acid groups due to the modification. The pHpzc showed a decrease due to modification of the pine cone biomass. The pHpzc values for the pine and modified pine cone biomass were found to be: Raw = 7.49, Raw-HMDI modified = 6.68, Fenton treated pine = 5.40 and Fenton-HMDI modified = 6.12. The optimum pH for the adsorption of 2-nitrophenol onto raw pine and modified pine cone biomass was determined to be 6. The optimum adsorbent dosage was determined as 1.5 g/dm3. The adsorption kinetics show a good fit with the pseudo-second-order model. This suggests that surface adsorption is the controlling step in the adsorption of 2-nitrophenol onto pine cone biomass. The analysis of diffusion processes showed that the initial rapid stage during the adsorption is due to external mass transfer processes. The adsorption experimental data also showed that pore diffusion was rate-limiting amongst the diffusion processes. Pine modification using Fenton’s reagent and 1.6-hexamethylene diisocyanate increased magnitude of kinetic and diffusion parameters. Experimental data for 2-nitrophenol adsorption onto pine and modified pine cone biomass showed better correlation with the Redlich-Peterson and Hill isotherm models and poor correlation with the Freundlich isotherm model. This suggests that the mechanism does not show complete multilayer coverage with cooperative phenomena between adsorbate molecules. Thermodynamic parameters showed that the adsorption is feasible, spontaneous, and exothermic and results in a decrease in degree of disorder at the solid/liquid interface. An increase in temperature resulted in a decrease in adsorption capacity showing that the adsorption is physical. Pine modification using Fenton’s reagent and 1.6-hexamethylene diisocyanate increased magnitude of kinetic, diffusion and isotherm parameters. The kinetic and equilibrium results show that the adsorption of 2-nitrophenol onto pine cone biomass follows the order: Fenton treated-HMDI > Fenton treated > Raw-HMDI > Raw. Hence, it can be concluded that Fenton treatment and HMDI cross-linking modification did increase the adsorptive capabilities of the pine cone biomass. / VUT Research Directorate
72

Tratabilidade de águas residuárias de indústrias petroquímicas - estudo de caso. / Treatability of petrochemical industries wastewaters - case study.

Hilsdorf, Antonio Sérgio de Carvalho 02 September 2008 (has links)
O tratamento de águas residuárias industriais, submetido constantemente a cargas de choque, é pouco estudado no Brasil, sendo limitado o grau de conhecimento que se tem no mundo sobre os mecanismos de remoção de disruptores endócrinos nos sistemas de tratamento físico-químicos e biológicos. O presente trabalho traz um estudo de caso, envolvendo uma indústria com uma composição de produtos muito diversificada, com despejos líquidos de unidades isoladas de qualidades diversas e que tem como uma das principais matérias-primas, nonil fenóis, conhecidos disruptores endócrinos. Os mecanismos de remoção de carga orgânica e a avaliação da toxicidade da água residuária ao processo biológico de tratamento foram estudados em escala de laboratório, enquanto que a sua tratabilidade por coagulação, floculação, flotação com ar dissolvido seguido de sistema de lodos ativados, em escala piloto. Avaliou-se, também, a aplicabilidade do tratamento biológico com carvão ativado em pó. A grande variação qualitativa e quantitativa da água residuária bruta requer uma unidade de equalização com tempo de detenção de pelo menos 30 horas. O maior responsável por esta variação de qualidade é o processo da unidade química, cujo efluente é proveniente de lavagens de tanques e reatores. Apesar da reduzida eficiência de remoção de DQO obtida com a coagulação, floculação e flotação com ar dissolvido (20 a 30%), constatou-se que este tratamento é essencial para a redução da toxicidade ao processo biológico. A dosagem de coagulante e o pH ótimos variam conforme a característica do despejo e devem ser determinadas diariamente. No sistema biológico, observou-se uma remoção significativa da DQO do efluente bruto gerado na indústria, não apenas por biodegradação, mas também por volatilização e adsorção. Os testes de bancada evidenciaram remoções de DQO por arraste com ar de 47 a 77 % e por adsorção no lodo biológico, de 42%. Apesar dos constantes choques de carga orgânica e de poluentes tóxicos, conseguiu-se atingir o estado estacionário com variações máximas da concentração de sólidos em suspensão voláteis no tanque de aeração entre 20 e 30%. Neste período, a idade do lodo situou-se em torno de 25 a 30 dias e o tempo de detenção hidráulico foi de 3,8 dias. A eficiência média de remoção de DQO neste período foi de 86%. Os testes com a unidade piloto demonstraram que a utilização de carvão ativado em pó (CAP) produz resultados satisfatórios, comprovando a redução de poluentes tóxicos da água residuária e refletindo em uma significativa melhora na biodegradabilidade do efluente, com aumento da concentração de sólidos em suspensão voláteis no tanque de aeração (de 1380 mg/L para 3820 mg/L) e redução da amplitude de variação da DQO do efluente tratado que passou de 600 a 3200 mgO2/L para o sistema sem CAP para 300 a 600 mgO2/L para o sistema com CAP. Notou-se, também, com a adição de CAP, melhoria na sedimentação do lodo. Pode-se concluir também que o sistema de tratamento atendeu a legislação atual do Estado de São Paulo, com uma remoção média de 80% da DBO5. / Wastewater treatment systems continuously receiving shock loads and the behavior of contaminants under unsteady state conditions are not very well documented in our country, with limited degree of knowledge in the world on the removal of specific pollutants like endocrine disrupting chemicals (EDC) in physical chemical and biological wastewater treatment systems. The present work brings a case study regarding an industry which wastewaters were generated from plants with multiproducts and campaign production with variable composition, and with nonylphenols as one of their raw materials which is known as an endocrine disrupting chemical. The organic load and toxicity removal mechanisms of the wastewater to the biological treatment were studied in bench scale whilst their treatability was evaluated through coagulation, flocculation, dissolved air flotation followed by activated sludge, in pilot scale. The feasibility of the addition of powdered activated carbon to the biological system was also studied. The large qualitative and quantitative variability of the wastewater requires an equalization time of at least 30 hours. The main responsible for this variability in quality is the chemical unit process which wastewaters are originated from reactors and tanks cleanings. Although the low efficiency in COD removal obtained with coagulation, flocculation and dissolved air flotation (20 to 30%), it was found that this process is essential to the toxicity reduction for the biological process. Optimum pH and coagulant dose vary with the wastewater characteristics, and must be determined on a daily basis. On the biological system, it was observed important raw wastewater COD elimination not only through biodegradation, but also through volatilization and adsorption. Bench tests revealed COD elimination of 47 to 77% by air stripping and 42% by adsorption onto the biological sludge. Despite of constant organic and toxic shock loads, it had been possible to reach the steady state during which the maximum variation on the volatile suspended solids concentration was 20 to 30%. During this period, sludge age was around 25 to 30 days, and the hydraulic detention time was 3,8 days. Average efficiency on COD removal in this period was 86%. Tests results with PAC dosage on the pilot plant showed satisfactory, proving the reduction of toxic compounds from the wastewater and resulting in biodegradability improvement. The increase of volatile suspended solids in the aeration tank was from 1380 mg/L to 3820 mg/L, and reduction in the range of variation of remaining treated water COD from 600 to 3200 mgO2/L (system without CAP) down to 300 to 600 mgO2/L (system with CAP). The improvement on the sludge sedimentation with PAC addition was also remarkable. One can also conclude the treatment system attained the current legislation of the State of São Paulo, with 80% BOD5 removal.
73

Tratabilidade de águas residuárias contendo poluentes perigosos: estudo de caso. / Treatability of hazardous industrial wastewater: case study.

Morita, Dione Mari 29 September 1993 (has links)
O trabalho foi desenvolvido com o objetivo de caracterizar e estudar formas de tratamento de águas residuárias de indústrias de refino de óleo lubrificante e de recuperação de solventes. A fase preliminar teve por objetivo avaliar a biodegradabilidade do despejo combinado dessas duas indústrias. A segunda foi realizada em instalação piloto composta, basicamente, de uma unidade de arraste com ar/tanque de equalização, tanques de correção de pH e de aeração com tempos de detenção distintos, seguidos de tanques de sedimentação. Foram executados testes para avaliar a remoção de material solúvel em n-hexano do despejo da indústria de refino de óleo lubrificante e do efluente final. A unidade de arraste com ar difuso operando com subpressão de 15 mmhg a saída dos gases, vazão específica de ar de 20 ml/l min. E tempo de detenção de 5 dias foi eficiente na remoção de acetona, piridina, benzeno, tolueno, hexano, metil etil cetona e provavelmente solventes clorados. Não apresentou remoção significativa de álcoois, que foram eficientemente degradados no sistema biológico subsequente. Obteve-se remoções superiores a 90%, em termos de dbo e dqo, no processo biológico com tempos de detenção de 20 e 30 dias, e em torno de 80% para os demais. Os sistemas biológicos responderam bem as cargas transientes de solventes, exceto para o tolueno e o álcool isopropílico. / Traditionally, raw materials from solvent recovery and from reclaimed lubricating oil industries are considered hazardous solid waste. Consequently, the best control technology is incineration. This work was developed in order to characterize and to study ways of treating wastewaters from lubricating oil refinery and solvent recovery industries. The experimental part was divided in two phases. The preliminar step aimed to evaluate the biodegradability of combined wastewater from both industries. The second phase was basically carried out in a pilot plant composed by an air stripping unit/equalization tank, pH correction tanks and bioreactors with different retention times, followed by sedimentation tanks. Other than these assays, tests were performed to evaluate the removal of soluble material in n-hexane of the wastewater of the lubricating oil refinery industry and of the supernatant of the sedimentation tank after the bioreactor of 20 days retention.The buble aeration unit operating with a 15 mmHg suppresion to the gas exit, with a specific air flow of 20 mL/L.min. and with a retention time of 5 days was efficient to remove acetone, pyridine, benzene, toluene, hexane, methyl ethyl ketone and probably chlorinated solvents. There was no significative removal of alcohols, that were efficiently degraded in the subsequent biological system. BOD and COD removal efficiencies were better than 90% in the biological process with retention times of 20 and 30 days, and about 80% for the rest. The responses of biological systems to the transient inputs of solvents were well, except for toluene and isopropilic alcohol. Several physico-chemical processes for soluble material in n-hexane removal were studied. The only one to present effluent concentration under the legal limit was the addition of the sodium xylene-sulphonate base demulsifier to the supernatant of the sedimentation tank the bioreactor of 20 days retention.
74

Tratabilidade de águas residuárias contendo poluentes perigosos: estudo de caso. / Treatability of hazardous industrial wastewater: case study.

Dione Mari Morita 29 September 1993 (has links)
O trabalho foi desenvolvido com o objetivo de caracterizar e estudar formas de tratamento de águas residuárias de indústrias de refino de óleo lubrificante e de recuperação de solventes. A fase preliminar teve por objetivo avaliar a biodegradabilidade do despejo combinado dessas duas indústrias. A segunda foi realizada em instalação piloto composta, basicamente, de uma unidade de arraste com ar/tanque de equalização, tanques de correção de pH e de aeração com tempos de detenção distintos, seguidos de tanques de sedimentação. Foram executados testes para avaliar a remoção de material solúvel em n-hexano do despejo da indústria de refino de óleo lubrificante e do efluente final. A unidade de arraste com ar difuso operando com subpressão de 15 mmhg a saída dos gases, vazão específica de ar de 20 ml/l min. E tempo de detenção de 5 dias foi eficiente na remoção de acetona, piridina, benzeno, tolueno, hexano, metil etil cetona e provavelmente solventes clorados. Não apresentou remoção significativa de álcoois, que foram eficientemente degradados no sistema biológico subsequente. Obteve-se remoções superiores a 90%, em termos de dbo e dqo, no processo biológico com tempos de detenção de 20 e 30 dias, e em torno de 80% para os demais. Os sistemas biológicos responderam bem as cargas transientes de solventes, exceto para o tolueno e o álcool isopropílico. / Traditionally, raw materials from solvent recovery and from reclaimed lubricating oil industries are considered hazardous solid waste. Consequently, the best control technology is incineration. This work was developed in order to characterize and to study ways of treating wastewaters from lubricating oil refinery and solvent recovery industries. The experimental part was divided in two phases. The preliminar step aimed to evaluate the biodegradability of combined wastewater from both industries. The second phase was basically carried out in a pilot plant composed by an air stripping unit/equalization tank, pH correction tanks and bioreactors with different retention times, followed by sedimentation tanks. Other than these assays, tests were performed to evaluate the removal of soluble material in n-hexane of the wastewater of the lubricating oil refinery industry and of the supernatant of the sedimentation tank after the bioreactor of 20 days retention.The buble aeration unit operating with a 15 mmHg suppresion to the gas exit, with a specific air flow of 20 mL/L.min. and with a retention time of 5 days was efficient to remove acetone, pyridine, benzene, toluene, hexane, methyl ethyl ketone and probably chlorinated solvents. There was no significative removal of alcohols, that were efficiently degraded in the subsequent biological system. BOD and COD removal efficiencies were better than 90% in the biological process with retention times of 20 and 30 days, and about 80% for the rest. The responses of biological systems to the transient inputs of solvents were well, except for toluene and isopropilic alcohol. Several physico-chemical processes for soluble material in n-hexane removal were studied. The only one to present effluent concentration under the legal limit was the addition of the sodium xylene-sulphonate base demulsifier to the supernatant of the sedimentation tank the bioreactor of 20 days retention.
75

Tratabilidade de águas residuárias de indústrias petroquímicas - estudo de caso. / Treatability of petrochemical industries wastewaters - case study.

Antonio Sérgio de Carvalho Hilsdorf 02 September 2008 (has links)
O tratamento de águas residuárias industriais, submetido constantemente a cargas de choque, é pouco estudado no Brasil, sendo limitado o grau de conhecimento que se tem no mundo sobre os mecanismos de remoção de disruptores endócrinos nos sistemas de tratamento físico-químicos e biológicos. O presente trabalho traz um estudo de caso, envolvendo uma indústria com uma composição de produtos muito diversificada, com despejos líquidos de unidades isoladas de qualidades diversas e que tem como uma das principais matérias-primas, nonil fenóis, conhecidos disruptores endócrinos. Os mecanismos de remoção de carga orgânica e a avaliação da toxicidade da água residuária ao processo biológico de tratamento foram estudados em escala de laboratório, enquanto que a sua tratabilidade por coagulação, floculação, flotação com ar dissolvido seguido de sistema de lodos ativados, em escala piloto. Avaliou-se, também, a aplicabilidade do tratamento biológico com carvão ativado em pó. A grande variação qualitativa e quantitativa da água residuária bruta requer uma unidade de equalização com tempo de detenção de pelo menos 30 horas. O maior responsável por esta variação de qualidade é o processo da unidade química, cujo efluente é proveniente de lavagens de tanques e reatores. Apesar da reduzida eficiência de remoção de DQO obtida com a coagulação, floculação e flotação com ar dissolvido (20 a 30%), constatou-se que este tratamento é essencial para a redução da toxicidade ao processo biológico. A dosagem de coagulante e o pH ótimos variam conforme a característica do despejo e devem ser determinadas diariamente. No sistema biológico, observou-se uma remoção significativa da DQO do efluente bruto gerado na indústria, não apenas por biodegradação, mas também por volatilização e adsorção. Os testes de bancada evidenciaram remoções de DQO por arraste com ar de 47 a 77 % e por adsorção no lodo biológico, de 42%. Apesar dos constantes choques de carga orgânica e de poluentes tóxicos, conseguiu-se atingir o estado estacionário com variações máximas da concentração de sólidos em suspensão voláteis no tanque de aeração entre 20 e 30%. Neste período, a idade do lodo situou-se em torno de 25 a 30 dias e o tempo de detenção hidráulico foi de 3,8 dias. A eficiência média de remoção de DQO neste período foi de 86%. Os testes com a unidade piloto demonstraram que a utilização de carvão ativado em pó (CAP) produz resultados satisfatórios, comprovando a redução de poluentes tóxicos da água residuária e refletindo em uma significativa melhora na biodegradabilidade do efluente, com aumento da concentração de sólidos em suspensão voláteis no tanque de aeração (de 1380 mg/L para 3820 mg/L) e redução da amplitude de variação da DQO do efluente tratado que passou de 600 a 3200 mgO2/L para o sistema sem CAP para 300 a 600 mgO2/L para o sistema com CAP. Notou-se, também, com a adição de CAP, melhoria na sedimentação do lodo. Pode-se concluir também que o sistema de tratamento atendeu a legislação atual do Estado de São Paulo, com uma remoção média de 80% da DBO5. / Wastewater treatment systems continuously receiving shock loads and the behavior of contaminants under unsteady state conditions are not very well documented in our country, with limited degree of knowledge in the world on the removal of specific pollutants like endocrine disrupting chemicals (EDC) in physical chemical and biological wastewater treatment systems. The present work brings a case study regarding an industry which wastewaters were generated from plants with multiproducts and campaign production with variable composition, and with nonylphenols as one of their raw materials which is known as an endocrine disrupting chemical. The organic load and toxicity removal mechanisms of the wastewater to the biological treatment were studied in bench scale whilst their treatability was evaluated through coagulation, flocculation, dissolved air flotation followed by activated sludge, in pilot scale. The feasibility of the addition of powdered activated carbon to the biological system was also studied. The large qualitative and quantitative variability of the wastewater requires an equalization time of at least 30 hours. The main responsible for this variability in quality is the chemical unit process which wastewaters are originated from reactors and tanks cleanings. Although the low efficiency in COD removal obtained with coagulation, flocculation and dissolved air flotation (20 to 30%), it was found that this process is essential to the toxicity reduction for the biological process. Optimum pH and coagulant dose vary with the wastewater characteristics, and must be determined on a daily basis. On the biological system, it was observed important raw wastewater COD elimination not only through biodegradation, but also through volatilization and adsorption. Bench tests revealed COD elimination of 47 to 77% by air stripping and 42% by adsorption onto the biological sludge. Despite of constant organic and toxic shock loads, it had been possible to reach the steady state during which the maximum variation on the volatile suspended solids concentration was 20 to 30%. During this period, sludge age was around 25 to 30 days, and the hydraulic detention time was 3,8 days. Average efficiency on COD removal in this period was 86%. Tests results with PAC dosage on the pilot plant showed satisfactory, proving the reduction of toxic compounds from the wastewater and resulting in biodegradability improvement. The increase of volatile suspended solids in the aeration tank was from 1380 mg/L to 3820 mg/L, and reduction in the range of variation of remaining treated water COD from 600 to 3200 mgO2/L (system without CAP) down to 300 to 600 mgO2/L (system with CAP). The improvement on the sludge sedimentation with PAC addition was also remarkable. One can also conclude the treatment system attained the current legislation of the State of São Paulo, with 80% BOD5 removal.
76

Obtenção de extrato proveniente do aproveitamento de residuo da industria sucroalcooleira, utilizando CO2 supercritico : parametros de processo e estimativa do custo de manufatura / Obtaining extract from the residue of the sugar cane and alcohol industrial using supercritical CO2 : process parameter and estimative of the cost of manufacturing

Shintaku, Alberto 05 August 2006 (has links)
Orientadores: Maria Angela de Almeida Meireles, Carlos Eduardo Vaz Rossell / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-06T15:36:00Z (GMT). No. of bitstreams: 1 Shintaku_Alberto_M.pdf: 7098448 bytes, checksum: b538eba167ccbd49382fabb569cc75ee (MD5) Previous issue date: 2006 / Resumo: Neste trabalho estimou-se o custo de obtenção de extratos de cera, por extração supercrítica, a partir do resíduo da industria de açúcar e álcool, a torta de filtro. Foram realizados ensaios para determinação das isotermas de rendimento global, as curvas globais de extração (cinéticas de extração) e a identificação da composição química dos extratos obtidos. Na determinação da isoterma de rendimento global foram estudadas as pressões no intervalo de 100 a 350 bar com variações de 50 bar para as temperaturas de 30 e 50 ºC inicialmente para a matéria prima A. A quantidade utilizada de matéria prima (matéria prima A) foi de 2,5 gramas e uma vazão de CO2 de 0,249 ± 0,002 kg/h. Todos os ensaios foram realizados em duplicata e o tempo de extração de 60 min.. Para obtenção das curvas globais de extração foram utilizadas matérias primas distintas provenientes de 3 regiões do estado de São Paulo (matérias primas A, B e C). A temperatura de 50 ºC foi escolhida inicialmente para a matéria prima A, com as pressões de 200 bar e 350 bar respectivamente. Em seguida foi utilizado o binômio: temperatura e pressão, de 60 ºC e 200 bar para a matéria prima A, B e C sendo a temperatura escolhida pela característica do extrato de alta viscosidade (sólido à temperatura ambiente). A quantidade de matéria prima utilizada em cada ensaio foi de 25 gramas, uma vazão de 0,249 ± 0,003 kg/h de CO2, que fornece uma relação de 15 kg de CO2/kg de matéria prima. O tempo de extração utilizado para cada ensaio foi de 360 minutos. A partir do rendimento de extração, do tempo de extração do período CER (Constant Extraction Rate) e das características físicas da matéria prima (densidade, porosidade, etc.), foi estimada a capacidade dos extratores tomando-se o cuidado de dimensionar um extrator compatível com a capacidade de extratores comerciais existentes. Esta estimativa de capacidade permitiu a obtenção do custo do produto, a partir de uma análise econômica. A análise de sensibilidade do custo de produção para variações no custo de investimento, custo de insumos, custo de energia, custo de mão de obra e rendimento de extração, mostrou que o mesmo é influenciado principalmente pela variação no custo de investimento e pela variação do rendimento de extração. O custo de produção do extrato de cera foi estimado em US$ 13.626,93/tonelada / Abstract: The purpose of this work was to determine the manufacturing cost for the wax extract obtained from residues of the sugar cane and ethanol industry (filter cake), using SFE (Supercritical Fluid Extraction). Experiments were accomplished to determine the global yield isotherms, the overall extraction curves (kinetic of extraction) and to identification chemical composition of the extracts. The global yield isotherms were determined at the pressures of 100, 150, 200, 250, 300 and 350 bar and temperatures of 50 ºC and 30 ºC The amount of raw material (raw material A) used in each trial was 2.5 grams and a CO2 flowrate of 0.249 ± 0.002 kg/h. The experiments were duplicated. In order to determine the overall extraction curves (OEC), distinct raw materials were used from three different regions of São Paulo State (raw materials A, B and C). The OEC for the raw material A was initially determined at 50 ºC, with 200 bar and 350 bar of pressure respectively. In spite of 50 ºC be chosen initially, the experiments were accomplished in the SFE (Supercritical Fluid Extraction) equipment at 60 ºC and 200 bar for the raw material A, B and C being the temperature chosen due to characteristics of extract high viscosity (solid state at the ambient or room temperature). A 25 grams raw material sample was used in each trial with an outflow of 0,249 ± 0,003 kg/h of CO2 (a relation of 15 kg of CO2/kg of raw material). The extractors capacity was estimated from the extraction yield, the extraction time of Constant Extraction Rate period (CER) and the physical characteristics of the raw material (density, porosity, etc.). Extractors sizing considered the compatibility with existent extractors commercial capacity. This capacity estimation allowed the attainment of the product cost, from an economic analysis where investment cost, equipment cost, cost of operating labor, cost of operating supplies, etc. have been determined, composing the total extraction cost. The cost sensitivity was analyzed for variations in the investment cost, cost of operating supplies, energy cost, cost of operating labor and extraction income, showing that the production cost is influenced mainly by the variation in the investment cost and by the variation of the extraction yield. The determined wax extract obtaining cost, with SFE technology, was US$ 13,626.93/ton except for taxes / Mestrado / Mestre em Engenharia de Alimentos
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Estudo de tratabilidade de efluentes de industria de catalisadores quimicos por lodos ativados por batelada (LAB) : Degussa, Americana, SP / Treatment study of effluents from chemical catalyst industry by activated sludge using sequencing batch reactor: Degussa, Americana, SP, Brrazil

Higa, Marcia Fernanda 23 February 2005 (has links)
Orientador: Carlos Gomes da Nave Mendes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-07T08:45:44Z (GMT). No. of bitstreams: 1 Higa_MarciaFernanda_M.pdf: 694032 bytes, checksum: 6aeb2dc109b978afe0fa9cd54037a168 (MD5) Previous issue date: 2005 / Resumo: O presente trabalho teve como objetivo principal a investigação do potencial de utilização de reatores de lodos ativados intermitentes para o tratamento conjunto de diversos tipos de águas residuárias geradas na indústria de catalisadores químicos Degussa, localizada no município de Americana - SP, incluindo-se os esgotos sanitários. Foram utilizados reatores de bancada e estudadas duas idades de lodo, simulando-se a aeração convencional e aeração prolongada. Foram investigados também quatro cenários possíveis, ou seja, quatro amostras compostas distintas de efluentes, de serem implantados em escala real. Os resultados obtidos mostraram que o sistema de aeração prolongada foi preferível em todas as situações estudadas, e que três dos cenários foram adequados ao tratamento biológico de lodos ativados por batelada, uma vez que apresentaram eficiências de redução dos valores de DQO superiores à 80%. No caso do tratamento conjunto de todas as águas residuárias da indústria, essa eficiência foi de 85,7 e 92,1% para as idades de lodo de 7 e 20 dias, respectivamente, indicando que o uso de reatores biológicos de lodos ativados por batelada constituiu-se em alternativa viável para a Degussa / Abstract: The present work had as main objective the investigation of the utilization potential of activated sludge sequencing batch reactors on the combined treatment of several kinds of wastewaters originated in the chemical catalyst industry Degussa, located in Americana - SP, including the domestic sewage. Workbench reactors were used and two sludge ages were studied, simulating the conventional and the prolonged aerations. Four possible sceneries, or four different effluent compound samples, possible of being full-scale introduced, were also investigated. The results showed that the system of prolonged aeration was preferable in alI the studied situations, and that three of the sceneries were suitable for the biological treatment by activated sludge using sequencing batch reactors, once they achieved efficiencies of reduction in the COD values greater than 80%. In the treatment inc1uding the total reunion of the industry effluents, this efficiency was 85,7 and 92,1%, to the sludge age of 7 and 20 days, respectively, indicating that the use of activated sludge sequencing batch biological reactors is a feasible alternative for Degussa / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
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Avloppsrening från småskalig processindustri / Wastewater treatment from small-scale process industry

Dahlström, Julia January 2020 (has links)
Småskaliga processindustrier är små industrier som genom ett småskaligt, hantverksmässigt eller lokalt förhållningssätt förädlar råvaror genom olika automatiserade processer. Vid förädlingen uppkommer stora mängder processavloppsvatten med stor organisk belastning som måste tas om hand på ett hållbart, resurseffektivt och miljömässigt sätt för att inte skada människa eller miljö. I denna studie undersöktes kvaliteten på processavloppsvatten från småskaliga slakterier, mejerier och bryggerier, samt hur hanteringen av processavloppsvattnet från dessa processindustrier ser ut i Sverige idag. Ytterligare utreddes hur reningstekniker för små avlopp kan användas för rening av processavloppsvatten från småskalig processindustri samt hur marknaden för användande av tekniker för små avlopp för rening av processavloppsvatten ser ut. Studien använde ett flertal metoder, litteraturstudie av småskaliga processindustrier och små avlopp, intervjuer och enkätundersökning av småskaliga slakterier, mejerier och bryggerier, samt intervjuer med tillverkare för tekniker för små avlopp. Resultatet visade att kvaliteten på processavloppsvattnet inte kunde redovisas för majoriteten av processindustrierna från intervjuer och enkätundersökning eftersom kvalitetsanalyser inte alltid verkar ske på processavloppsvattnet, varken före eller efter rening. Litteraturen beskrev vidare att prioriterade parametrar att rena för slakterier, mejerier och bryggerier främst är organiska ämnen (mätt som BOD eller COD), suspenderade ämnen, kväve, fosfor, samt pH. Dessa parametrar varierar mellan de olika typerna av processindustrierna och inom samma typ av processindustri. Variationerna anses utgöra en utmaning att hitta passande reningstekniker som fungerar i alla sammanhang. Angående vilka reningstekniker och avloppslösningar som används av småskaliga processindustrier visade resultatet att en stor andel av processindustrierna har intern rening, och knappt en tredjedel har anslutning till kommunalt avloppsnät. Processindustrier med intern rening vars processavloppsvatten dimensionerades till mindre än 100 personekvivalenter använder till övervägande del tekniker för rening av små avlopp, men andra avloppslösningar såsom gödselbrunn, reningsverk och biogasanläggning förekom även för större avloppsdimensioner. Reningstekniker för små avlopp för rening av processavloppsvatten, samt anpassade tekniker för processavloppsvatten, erbjuds till viss grad på dagens marknad men det finns fortfarande utmaningar för att kunna tillhandahålla lösningar för fler typer av processindustrier. Möjlighet att utjämna avloppsflöden och lösningar med större belastningskapacitet är fortfarande något som behöver utvecklas vidare. / Small-scale process industries are small, sometimes locally or artisanal, industries that produces their product through processing raw materials by using automated processes. Large volumes of wastewater effluent are produced by doing this, and this wastewater is characterized by high organic load and nutrients which must be treated in a sustainable way to not be harmful to humans nor the environment. This study evaluated industrial wastewater treatment from small-scale slaughterhouses, dairies and breweries, including wastewater characteristics of these types of process industries in Sweden today. The study also included an evaluation of decentralized wastewater treatment systems for small-scale industrial wastewater treatment and what the Swedish market can provide regarding small-scale industrial wastewater treatments. Different methods were used to reach this goal; a literature study regarding wastewater characteristics and treatment of industrial wastewater and decentralized wastewater treatment systems, interviews, and surveys of Swedish small-scale process industries, and finally interviews with manufacturers of decentralized wastewater treatment systems. The result showed that wastewater characteristics was not accessible from most of the Swedish small-scale process industries. They mostly do not analyze their wastewater neither before nor after wastewater treatment. Furthermore, it was described that highpriority wastewater characteristics for treatment according to the literature was BOD, COD, suspended solids, nitrogen, phosphorus, and pH. Variations of these characteristics is common both between different types of process industries and in the same type of industry. These variations are challenging in regard to finding suitable wastewater treatment techniques that is adequate in every situation. Wastewater treatment systems used today are mostly local at the site, it is around a third that have connection to municipal wastewater facilities. The most common local wastewater treatment for small process industries (less than 100 population equivalents) is decentralized wastewater treatment systems according to the interviews and surveys. Other wastewater treatments such as dung pits, wastewater treatment plants and biogas plants were also used for larger process industries. Decentralized wastewater treatment systems for industrial wastewater treatment and adapted small-scale industrial wastewater treatments can be found to some extent on the Swedish market today, but there are still some challenges to provide small-scale industrial wastewater treatment for every type of process industry. Solutions to level out intense wastewater flows and capacity to receive high effluent loads need to be further developed.
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Forward Osmosis Application in Manufacturing Industries: A Short Review

Haupt, Anita, Lerch, André 13 December 2018 (has links)
Forward osmosis (FO) is a membrane technology that uses the osmotic pressure difference to treat two fluids at a time giving the opportunity for an energy-efficient water and wastewater treatment. Various applications are possible; one of them is the application in industrial water management. In this review paper, the basic principle of FO is explained and the state-of-the-art regarding FO application in manufacturing industries is described. Examples of FO application were found for food and beverage industry, chemical industry, pharmaceutical industry, coal processing, micro algae cultivation, textile industry, pulp and paper industry, electronic industry, and car manufacturing. FO publications were also found about heavy metal elimination and cooling water treatment. However, so far FO was applied in lab-scale experiments only. The up-scaling on pilot- or full-scale will be the essential next step. Long-term fouling behavior, membrane cleaning methods, and operation procedures are essential points that need to be further investigated. Moreover, energetic and economic evaluations need to be performed before full-scale FO can be implemented in industries.
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Management of industrial wastewater discharges in river basins through agents'argumentation

Aulinas Masó, Montse 14 October 2009 (has links)
La gestió de l'aigua residual és una tasca complexa. Hi ha moltes substàncies contaminants conegudes però encara moltes per conèixer, i el seu efecte individual o col·lgectiu és difícil de predir. La identificació i avaluació dels impactes ambientals resultants de la interacció entre els sistemes naturals i socials és un assumpte multicriteri. Els gestors ambientals necessiten eines de suport pels seus diagnòstics per tal de solucionar problemes ambientals.Les contribucions d'aquest treball de recerca són dobles: primer, proposar l'ús d'un enfoc basat en la modelització amb agents per tal de conceptualitzar i integrar tots els elements que estan directament o indirectament involucrats en la gestió de l'aigua residual. Segon, proposar un marc basat en l'argumentació amb l'objectiu de permetre als agents raonar efectivament. La tesi conté alguns exemples reals per tal de mostrar com un marc basat amb agents que argumenten pot suportar diferents interessos i diferents perspectives. Conseqüentment, pot ajudar a construir un diàleg més informat i efectiu i per tant descriure millor les interaccions entre els agents. En aquest document es descriu primer el context estudiat, escalant el problema global de la gestió de la conca fluvial a la gestiódel sistema urbà d'aigües residuals, concretament l'escenari dels abocaments industrials. A continuació, s'analitza el sistema mitjançant la descripció d'agents que interaccionen. Finalment, es descriuen alguns prototips capaços de raonar i deliberar, basats en la lògica no monòtona i en un llenguatge declaratiu (answer set programming).És important remarcar que aquesta tesi enllaça dues disciplines: l'enginyeria ambiental (concretament l'àrea de la gestió de les aigües residuals) i les ciències de la computació (concretament l'àrea de la intel·ligència artificial), contribuint així a la multidisciplinarietat requerida per fer front al problema estudiat. L'enginyeria ambiental ens proporciona el coneixement del domini mentre que les ciències de la computació ens permeten estructurar i especificar aquest coneixement. / Wastewater management is a very complex task. There is a high number of known and an increasing number of unknown pollutants whose individual and collective effects are very difficult to predict. Identifying and evaluating the impacts of environmental problems resulting from the interactions between our social system and its natural environment is a multifaceted critical issue. Environmental managers require tools to support their diagnoses for solving these problems. The contributions of this research work are twofold: first, to propose the use of an agent-based modelling approach in order to conceptualize and integrate all elements that are directly or indirectly involved in wastewater management. Second, to propose a framework based on argumentation that allows to reason effectively. The thesis provide some real examples to show that an agent-based argumentation framework can deal with multiple interests and different agents' perspectives and goals. This help to build a more effective and informed dialog in order to better describe the interaction between agents. In this document we first describe the context under study, scaling down the global river basins system to the urban wastewater systems and giving some more details for the specific scenario of industrial wastewater discharges. Then, we analyze the system in describing intelligent agents that interact. Finally, we propose some reasoning and deliberation prototypes by using an argumentation framework founded on non-monotonic logics (i.e. permitting to learn things that were previously not known) and the answer set programming specification language (i.e. a declarative programming language). It is important to remark that this thesis links two disciplines: environmental engineering (specifically the area of wastewater management) and computer science (specifically the area of artificial intelligence), contributing to the required multidsciplinarity needed to confront the complexity of the problem under study. From environmental engineering we obtain the domain knowledge whereas the computer science field permits us to structure and specify this knowledge.

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