Orientador: José Vicente Hallak d'Angelo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-21T16:01:06Z (GMT). No. of bitstreams: 1 Leite_BrennoSantos_D.pdf: 2261733 bytes, checksum: 645cd7fdea0a4b3aadd5357222e37a40 (MD5) Previous issue date: 2012 / Resumo: O licor negro é um subproduto do processo de digestão da madeira em fábricas de celulose e papel, composto por frações orgânicas e inorgânicas. Após o processo de digestão, o licor negro apresenta um teor de sólidos secos de aproximadamente 15% e para que possa ser queimado na caldeira de recuperação química é necessário elevar esse teor para valores próximos de 75%. Este processo de concentração do licor é feito em um sistema de evaporação múltiplo efeito. Propriedades físico-químicas do licor, tais como massa específica, teor de sólidos secos, viscosidade e teor de sais de sódio sofrem forte dependência do tipo de madeira processada e das condições de operação durante o processo de digestão. O conhecimento destas propriedades e da relação entre elas auxilia no controle do processamento do licor e pode permitir um maior aproveitamento energético de toda a unidade de recuperação. Quando o licor negro atinge altas concentrações de sólidos (superiores a 50%), observa-se precipitação de sais responsáveis pela formação de incrustações na superfície de transferência de calor dos evaporadores e concentradores, reduzindo a eficiência do sistema de evaporação. O presente trabalho tem como objetivo geral, investigar e compreender o mecanismo de formação e precipitação de sais de sódio, durante o processo de concentração do licor negro, os quais podem formar incrustações que prejudicam o bom desempenho do processo, por meio de um estudo e correlação de suas propriedades físico-químicas, avaliando sua influência na solubilidade dos sais inorgânicos presente no licor. Ressalta-se que os primeiros sais a precipitarem são os sais de sódio, mais especificamente o carbonato e o sulfato de sódio. Sendo assim, compreender o mecanismo que promove a redução de sua solubilidade é muito importante para entender o comportamento dos demais sais presentes no licor negro. Foi possível desenvolver um modelo capaz de avaliar a solubilidade do sulfato de sulfato de sódio considerando as características especificas do licor negro. Também, com base neste modelo de solubilidade foi possível compreender a lógica do efeito da inversão de solubilidade de um determinado sal sobre o comportamento do sistema, possibilitando compreender o mecanismo de formação das primeiras precipitações no licor negro de eucalipto / Abstract: In pulp and paper mills the aqueous solution extracted from the pulping process in the wood digester is named black liquor, which consists of organic and inorganic compounds. When leaving the digester sector black liquor has about 15 %/mass of solids and to be used as a fuel in the recovery boiler it is necessary to raise this solids content to 75 %/mass, removing water in a battery of multiple effect evaporators. Some black liquor physical properties, such as density, solids content, viscosity and sodium salts content, are strongly dependent on the kind of wood processed (hardwood or softwood) and on operating conditions during the digestion process. Knowledge and comprehension of the relationship between these physical properties of black liquor are essential for studies aiming at a better energetic performance of the black liquor evaporation unit. When black liquor reaches higher solids content (above 50 %/mass), scaling formation is observed on the heat transfer surfaces of evaporators and concentrators, due to precipitation of sodium salts, reducing the overall efficiency of this equipment. The aim of this work is to investigate and comprehend the mechanism of formation and precipitation of sodium salts in eucalyptus black liquor evaporators, through the study of the relationship between some physical proprieties (density, viscosity, total solids content) evaluating their influence over the solubility of sodium salts content in industrial black liquor samples. This greater comprehension and knowledge of the mechanism which is responsible for the reduction of the solubility of these salts is very important for the development of alternative methods to avoid or reduce scaling formation. The results have shown that it is possible to use a model to estimate sodium sulfate solubility limit and comprehend the formation mechanism of the first scaling and the behavior of the salts in the system / Doutorado / Sistemas de Processos Quimicos e Informatica / Doutor em Engenharia Química

La liqueur noire est produite en grande quantité dans les papeteries, en co-produit de la pâte à papier. Issue de la transformation du bois, elle représente une source importante de biopolymères non concurrentielle à l’industrie alimentaire. Par dispersion d’une phase organique dans la liqueur noire, des émulsions concentrées et stables ont été obtenues. Parmi les phases dispersées envisagées, l’huile de ricin et le 1,2-dichloroéthane ont été les plus adaptées. Par polymérisation de ces émulsions concentrées, la liqueur noire a permis d’obtenir des matériaux poreux appelés polyECs. L’analyse du cycle de vie a été appliquée tout au long de la préparation des polyECs et a montré que l’utilisation du 1,2-dichloroéthane, en tant que phase dispersée, serait moins néfaste pour l’environnement que l’utilisation de l’huile de ricin. Après pyrolyse, la matrice polymère des polyECs est devenue carbonée pour donner des carbones poreux, les carboECs. Grâce à leur structure microporeuse et mésoporeuse, ces carboECs biosourcés présentent un intérêt pour le stockage d’énergie, notamment les supercondensateurs. Des essais préliminaires ont montré que les performances électrochimiques des carboECs étaient comparables à la littérature. De par le choix d’un co-produit issu de la biomasse comme matière première, l’élaboration des carboECs de liqueur noire s’inscrit dans une démarche d’éco-conception. Afin de vérifier cette démarche, les carboECs issus de liqueur noire ont été comparés à des carboECs issus de poly(styrène-co-divinylbenzène), par l’analyse du cycle de vie. Cette étude comparative a montré que le procédé basé sur la liqueur noire aurait un profil écologique plus avantageux que le procédé dit pétrochimique. / Black liquor is a by-product of paper pulp production and is daily produced in large quantities. Non-competitive to the food industry, this wood-based by-product is an important source of biopolymers. Black-liquor based concentrated and stable emulsions were obtained by dispersing an organic phase into black liquor. Among the considered dispersed phases, castor oil and ethylene dichloride were the most suited. Similar materials were prepared by polymerising the concentrated emulsions containing those dispersed phases. The obtained porous monoliths, called polyECs, were compared by life cycle assessment. The results showed that using ethylene dichloride as the dispersed phase was more beneficial for the environment than using castor oil. Through pyrolysis, the polymeric matrix of the polyECs was processed into carbon to produce carboECs. The bio-based porous carbons presented a microporous and a mesoporous structure that is of interest for energy storage, in particularly supercapacitors. The exploratory tests showed that the carboECs efficiency as supercapacitors were similar to what found in literature. The choice of black liquor as the main raw material was made through an eco-design approach. To comfort that approach, the black-liquor-based carboECs were compared to a poly(styrene-co-divinylbenzene)-based carboECs using life cycle assessment. This study showed that using black liquor instead of styrene/divinylbenzene is beneficial.

Målet med den här studien är att förhindra effektivitetssänkningar i moderna biologiska reningsanläggningar för skogsindustriella avloppsvatten. Biologiska processer är vanligtvis effektiva när det gäller att reducera lättnedbrytbart organiskt material. Eftersom den utgörs av levande mikroorganismer (MO) är tekniken känslig. Toxiska ämnen kan döda en kultur av MO. Innan de har ökat i antal igen kommer reduktionseffektiviteten att vara påverkad för en ansenlig tid framöver. I ett pappers- och massabruk finns många typer av vätskor som oavsiktligt kan hamna i reningsanläggningen. I den här studien har svartluts inverkan på reduktionsgraden studerats. Biologiska reningsverk har använts under en lång tid. De har utvecklats från att vara generella reningsverk till att bli konceptanläggningar i flera steg, där varje steg har designats för sitt eget syfte med specifika MO. I det här arbetet har ett MultiBio-koncept vid Gruvön Bruk studerats. En anläggning i laboratorieskala har byggts för svartlutsförsöken. Resultatet har jämförts mot simulerade värden och värden från bruket. När ett spill av svartlut passerar genom en MultiBio späds det ut mellan varje steg. Halten av svartlut är hög i de första stegen vilka påverkas kraftigt. I de första stegen lever snabbväxande organismer som återhämtar sig på ett par dagar. De mer känsliga aktivslamstegen finns längre bak i reningsverket och är skyddade från toxiska koncentrationer av svartlut. Endast vid försök med 24-timmarstillsatser blev koncentrationen av svartlut så hög att den påverkade MO negativt. Den biologiska processen i ett reningsverk kan störas om MO förnekas något essentiellt behov. En biologisk process har ett flertal behov, bland annat behöver aeroba MO löst syre. Eftersom syresättning av vattnet är energikrävande och kostsamt är det inte problemfritt att skapa en omgivning som ger hög effektivitet samtidigt som man strävar efter att sänka energiförbrukningen. I avhandlingen beskrivs ett tillvägagångssätt för att studera energieffektiv syresättning. / The aim of this study is to prevent efficiency reduction in modern wastewater treatment plants for forest industry effluents. Biological processes are usually efficient in reducing biodegradable organic material. Since the technique depends on living microorganisms (MO) it is sensitive. Toxic substances can kill the population. It takes considerable time for the MOs to grow in number and the treatment efficiency will be affected accordingly. In a pulp and paper mill, a number of liquors are handled that can reach the treatment plant by accident. In this study the impact of black liquor spills on treatment efficiency has been studied. Biological treatment methods have been used for a long time. They have developed from general treatment plants to multiple stage concepts, where each stage is designed for its own purpose with specific MO cultures. In this thesis, a plant with the MultiBio concept, located at Gruvön Mill in Sweden has been studied. A laboratory scale MultiBio plant has been constructed for the trials in which efficiency during black liquor exposure has been measured. The measured laboratory results were evaluated by comparing them with simulated values and a mill case. When a shock of toxic black liquor passing through a MultiBio concept, the black liquor is diluted between the compartments. The first compartments that are exposed to high concentrations of black liquor are affected negatively. The MOs in the first compartment are fast growing and recover in a few days. The more sensitive activated sludge compartments are located further on in the plant. A toxic concentration is found in the activated sludge compartments only when the duration of the spill is 24 hours or more. Denying the MOs their needs can disturb biological treatments. Among many things, a biological process needs dissolved oxygen. Since aeration is energy consuming and expensive, there is a conflict between gaining high efficiency and, at the same time, decreasing the energy consumption. In this study, an approach to saving energy for aeration is initiated.

O avanço da capacidade do processamento dos computadores e do desenvolvimento de métodos numéricos tem proporcionado ferramentas de modelagem, projeto e otimização cada vez mais eficientes para a constante melhoria de caldeiras de recuperação química Kraft. Dentre as técnicas utilizadas, os modelos CFD abrangentes tem sido empregados nos últimos anos para representar a operação da caldeira de recuperação considerando o maior número possível processos vinculados ao escoamento dos gases de combustão. O presente trabalho busca desenvolver um modelo CFD abrangente considerando o escoamento turbulento dos gases de combustão, o arraste das gotas de licor, a combustão homogênea dos voláteis em fase gasosa, as etapas de combustão heterogênea do licor preto e uma representação simplificada do leito carbonizado. Os resultados se mostraram coerentes com o comportamento apresentado na literatura. A simulação do modelo permite análise dos projetos e das operações da caldeira. / The advance of computer processing power and the development of numerical methods promote more efficient tools for modeling, design and optimization aiming to increase improvements in Kraft recovery boilers. Among the available techniques, the comprehensive CFD models have been applied in the last years to represent the recovery boiler operation considering as much as possible processes linked with flue gas flow. The objective of present work is the development of a comprehensive CFD model considering turbulent flue gas flow, black liquor droplets drag, volatiles homogeneous combustion in gas phase, the steps of heterogeneous black liquor combustion and the simplified interaction between flue gas flow and char bed. The results have good agreement with boiler behavior presented in the literature. The simulation of the comprehensive model allows the analysis of design and operations of the boiler.

O avanço da capacidade do processamento dos computadores e do desenvolvimento de métodos numéricos tem proporcionado ferramentas de modelagem, projeto e otimização cada vez mais eficientes para a constante melhoria de caldeiras de recuperação química Kraft. Dentre as técnicas utilizadas, os modelos CFD abrangentes tem sido empregados nos últimos anos para representar a operação da caldeira de recuperação considerando o maior número possível processos vinculados ao escoamento dos gases de combustão. O presente trabalho busca desenvolver um modelo CFD abrangente considerando o escoamento turbulento dos gases de combustão, o arraste das gotas de licor, a combustão homogênea dos voláteis em fase gasosa, as etapas de combustão heterogênea do licor preto e uma representação simplificada do leito carbonizado. Os resultados se mostraram coerentes com o comportamento apresentado na literatura. A simulação do modelo permite análise dos projetos e das operações da caldeira. / The advance of computer processing power and the development of numerical methods promote more efficient tools for modeling, design and optimization aiming to increase improvements in Kraft recovery boilers. Among the available techniques, the comprehensive CFD models have been applied in the last years to represent the recovery boiler operation considering as much as possible processes linked with flue gas flow. The objective of present work is the development of a comprehensive CFD model considering turbulent flue gas flow, black liquor droplets drag, volatiles homogeneous combustion in gas phase, the steps of heterogeneous black liquor combustion and the simplified interaction between flue gas flow and char bed. The results have good agreement with boiler behavior presented in the literature. The simulation of the comprehensive model allows the analysis of design and operations of the boiler.

Made available in DSpace on 2017-07-21T20:42:41Z (GMT). No. of bitstreams: 1 ADRIANO BORGES MARTINS DA SILVA.pdf: 3121513 bytes, checksum: 07dee82c52a009778c436836023d7495 (MD5) Previous issue date: 2013-08-30 / The Kraft pulping process responsible for producing more than 130 million tons / year of all pulp produced in the world, is widely spread due to recycling of the chemicals used in pulping, NaOH and Na2S and co-generation of energy and steam for the chemical recovery process, where the residual weak black liquor from the wood cooking, is transformed into heavy black liquor by water evaporation and concentration of the liquor. Evaluating the chemical composition and the difference in solids caused by the water evaporation liquor has been proposed to study the corrosion process caused by the presence of black liquor in different types of metals used in evaporation plant, evaluating the physico-chemical properties of the black liquor in two distinct points of the evaporation plant, the impact caused by the effect of the presence of black liquor in 1020 alloy steel, stainless steel 304L and SAF 2205 duplex and compare the corrosion rate and polarization resistance experienced by the 1020 steel, stainless steel 304L and SAF 2205 duplex at two different concentrations. For verification of corrosion rate, electrochemical concepts were used according to the method ASTM G59-97, where electrodes were fabricated with three types of steels to be studied, the latter being immersed in the solution of black liquor, and evaluated their respective corrosion rates. In all conditions studied the 1020 alloy steel showed the worst corrosion rate and polarization resistance among the studied metals. For the 304L stainless steel and SAF 2205 duplex stainless steel both have acceptable corrosion rates for use with small additions between certain situations between 304L and SAF 2205 duplex steels, but as corrosion rates remained near the various situations studied so it is necessary to evaluate the financial viability of the application of one of the two leagues in the process. / O processo de polpação KRAFT responsável pela produção de mais de 130 milhões de toneladas/ano de toda celulose produzida no mundo, é amplamente difundido devido à reciclagem dos produtos químicos utilizados na polpação, NaOH e Na2S e a co-geração de energia e vapor durante o processo de recuperação química, onde o licor negro fraco residual do cozimento da madeira é transformado em licor negro forte, pela evaporação da água e concentração deste licor. Avaliando a composição química e a diferença no teor de sólidos ocasionado pela evaporação da água do licor foi proposto estudar o processo corrosivo causado pela presença de licor negro em diferentes tipos de metais utilizados em planta de evaporação, avaliando as propriedades físico-químicas do licor negro em dois pontos distintos da planta de evaporação, o impacto causado pelo efeito da presença de licor negro em ligas de aço 1020, aços inoxidáveis 304L e duplex SAF 2205 e comparar a taxa de corrosão e a resistência de polarização sofrida pelo aço 1020, aços inoxidáveis 304L e duplex SAF 2205 em duas concentrações diferentes. Para verificação da taxa de corrosão, foram utilizados conceitos eletroquímicos conforme a metodologia ASTM G59-97, onde foram confeccionados eletrodos com os três tipos de aços a serem estudados, sendo estes imersos na solução de licor negro, e avaliados suas respectivas taxas de corrosão e resistência de polarização. Em todas as condições estudadas o aço 1020 apresentou a pior taxa de corrosão entre os metais estudados. Para os aços inoxidáveis 304L e duplex SAF 2205, os dois apresentam taxas de corrosão aceitáveis para sua utilização, com pequenas vantagens entre determinadas situações entre os aços 304L e o duplex SAF 2205, porém como as taxas de corrosão se mantiveram próxima nas várias situações estudadas assim é necessário avaliar a viabilidade financeira da aplicação de uma das duas ligas em processo.

The world is about to shift from fossil fuel dependency to independency. The national agenda of Sweden has put forth future goals of becoming a zero net greenhouse gas emitter by the year 2045 and before that, having an 80 % fossil fuel independent transportation fleet by 2030. In order to achieve these goals, the form of energy used in the transport sector needs to be changed into a more renewable solution. Biogas could be part of the solution. The aim of this report has been to review earlier research regarding the future biogas potential in Sweden and to examine how realistic and practically feasible these are. Three of the substrates that has shown the highest future potential according to earlier research; energy crops, manure and black liquor has been chosen for investigating their future potential. Interviews was made with biogas researcher in Sweden as well as government employees working with biogas and other biofuels. Scenario building was another method used were the report have created four future scenarios with varying optimistically future economic and technical outcomes using more practical limitations and restrictions. The result was a combined future potential of between 0,42 – 77,54 TWh/annually from all three substrates using the values and information gathered from the interviewers regarding how to calculate the potential. The result shows that depending on how lucrative the future financial support systems and subsidies as well as how efficient the technical breakthroughs will be, biogas can become a large contributor to the transport sectors transition in becoming less fossil fuel dependent.

The risk for climate change is a growing concern for theglobal society. According to what is known as the Kyoto Protocol,developed countries have committed themselves to reduce theirgreenhouse gas (GHG) emissions. The purpose of this thesis hasbeen to analyse opportunities for CO2 reductions in Swedish pulpand paper mills. The pulp and paper industry accounts forsignificant shares of the Swedish utilisationof both electricityand, in particular, biomass fuels. In this thesis, it has been agoal to focus not only on the technical potential of alternativesfor CO2 reductions in the energy systems of pulp and paper mills,but also on analysing the costeffectiveness of the studiedmeasures. Moreover, the analysis has covered questions concerningthe capacity and willingness among the actors involved with thepulp and paper mills’energy systems to realise CO2reduction potentials. A broad techno-economical evaluation of available technologiesfor increased power production as well as more efficient energyutilisation is carried out. Furthermore, a more indepth analysisof pulp mill-based biomass energy with CO2 removal and permanentsequestration (BECS) is presented. An evaluation is made of thepotential for pulp and paper production with a negative CO2balance through the implementation of BECS. In recent yearsoutside suppliers, mainly energy service companies (ESCOs), havebegun to operate energy facilities in some Swedish pulp and papermills. Based on interviews with managers from pulp and papercompanies and ESCOs, the main driving forces behind theincreasing co-operation as well as the opportunities and riskswith energy related co-operation are presented. Furthermore, the technical possibility of carbon-negativitythrough the implementation of BECS is discussed in relation tocarbon management on both corporate and global levels. The extentto which CO2-reducing measures in pulp and paper mills arerealised will have an impact on Sweden’s capacity to reachCO2 reduction targets. Whether or not technologies for CO2capture and sequestration are developed and implemented inSwedish pulp mills has a very large impact on the size ofSweden’s long-term CO2 reduction potential. Moreover, thedevelopment of business and competence focus in pulp and papercompanies and ESCOs suggests that cooperation will become ofincreasing importance for future sustainable industrial energymanagement. <b>Keywords:</b>CO2 reduction, pulp and paper industry, energysystem, biomass, CO2 capture and sequestration, black liquor,gasification, power production, outsourcing, sustainable energymanagement

<p>The risk for climate change is a growing concern for theglobal society. According to what is known as the Kyoto Protocol,developed countries have committed themselves to reduce theirgreenhouse gas (GHG) emissions. The purpose of this thesis hasbeen to analyse opportunities for CO2 reductions in Swedish pulpand paper mills. The pulp and paper industry accounts forsignificant shares of the Swedish utilisationof both electricityand, in particular, biomass fuels. In this thesis, it has been agoal to focus not only on the technical potential of alternativesfor CO2 reductions in the energy systems of pulp and paper mills,but also on analysing the costeffectiveness of the studiedmeasures. Moreover, the analysis has covered questions concerningthe capacity and willingness among the actors involved with thepulp and paper mills’energy systems to realise CO2reduction potentials.</p><p>A broad techno-economical evaluation of available technologiesfor increased power production as well as more efficient energyutilisation is carried out. Furthermore, a more indepth analysisof pulp mill-based biomass energy with CO2 removal and permanentsequestration (BECS) is presented. An evaluation is made of thepotential for pulp and paper production with a negative CO2balance through the implementation of BECS. In recent yearsoutside suppliers, mainly energy service companies (ESCOs), havebegun to operate energy facilities in some Swedish pulp and papermills. Based on interviews with managers from pulp and papercompanies and ESCOs, the main driving forces behind theincreasing co-operation as well as the opportunities and riskswith energy related co-operation are presented.</p><p>Furthermore, the technical possibility of carbon-negativitythrough the implementation of BECS is discussed in relation tocarbon management on both corporate and global levels. The extentto which CO2-reducing measures in pulp and paper mills arerealised will have an impact on Sweden’s capacity to reachCO2 reduction targets. Whether or not technologies for CO2capture and sequestration are developed and implemented inSwedish pulp mills has a very large impact on the size ofSweden’s long-term CO2 reduction potential. Moreover, thedevelopment of business and competence focus in pulp and papercompanies and ESCOs suggests that cooperation will become ofincreasing importance for future sustainable industrial energymanagement.</p><p><b>Keywords:</b>CO2 reduction, pulp and paper industry, energysystem, biomass, CO2 capture and sequestration, black liquor,gasification, power production, outsourcing, sustainable energymanagement</p>

Resumo: A efetiva produção de etanol lignocelulósico depende de leveduras capazes de fermentar a fração hemicelulósica da biomassa lignocelulósica que é composta em sua maioria por xilose. Há uma grande dificuldade em encontrar esses microrganismos já que a capacidade de utilizar xilose como fonte de carbono não é apresentada pela maioria das leveduras. Neste trabalho leveduras isoladas de diferentes materiais da zona rural,foram testadas quanto à assimilação de xilose e glicose, e fermentação de xilose a 30°C, onde observou-se diferentes comportamentos entre diferentes linhagens da mesma espécie. As linhagens de leveduras isoladas foram identificadas pela técnica molecular PCR-RFLP empregando-se as regiôes ITS 5,8 S e D1/D2 do DNA ribossômico. Três leveduras identificadas como espécies de Cândida tropicalis foram avaliadas quanto a capacidade de produção de xilitol e etanol a partir de meio basal com xilose como única fonte de carbono e do licor negro da extração da celulose hidrolisado por enzimas do fungo Thermoascus aurantiacus. A produção de xilitol foi semelhante nos dois substratos, entretanto a produção de etanol foi maior quando o licor negro foi empregado, esses resultados mostraram que a quantidade e a natureza dos açúcares presentes nos meios foram um interferente maior no metabolismo da levedura que os compostos tóxicos presentes no licor negro / Abstract: The effective lignocellulosic ethanol production depends on yeasts that are able to ferment the hemicellulosic biomass fraction, which is mostly composed by xylose. There is a big difficulty in finding such microorganisms because most yeasts do not use xylose as a carbon source. In this work, yeasts isolated from different materials were tested for xylose and glucose assimilation and xylose fermentation at 30°C ,where it was observed different behaviors between strains of the same species. The strains isolated were identified by PCR-RFLP molecular technique employing the ITS 5,8 and D1/D2 regions of ribosomal DNA. Three yeasts were identified as Cândida tropicalis species and their ability to produce xylitol and ethanol from xylose and the black liquor from the cellulose extraction hydrolyzed by enzymes of the fungus Thermoascus aurantiacus was evaluated. The xylitol production was similar in both media, but the ethanol production was higher when the black liquor was used, these results shows that the quantity and nature of the sugars present in the media have a bigger interference in the metabolism of yeast to toxic compounds present in black liquor / Orientador: Roberto da Silva / Coorientador: Daniela Alonso Bocchini Martins / Banca: Eleni Gomes / Banca: Sandra Regina Ceccato Antonini / Mestre