This thesis will show the possibility for the development and use of an on-line model for application to continuous digesters for pulp production. The model is developed by using a program called Dymola (Dynamic Modeling Laboratory). What makes the Dymola software so well suited is that the program solves equations simultaneously. The model is a further development from the Purdue model [Bhartiya et al, 2003]. The main difference between this model and the Purdue model however, is the dynamics in the model. The dynamics are very important when you use the model for control purposes because the cooking process has long dead and retention times. The main purpose of this model is to use it for the advanced control of continuous digesters as well as giving the operators a better understanding of what happens in the cooking process when changes are made. The model will also be used for diagnostic purposes. Advanced control in this case is Model Predicted Control (MPC). The MPC will control the quality of the pulp “kappa” number and the chemical consumption during digestion. This thesis describes the model and results are shown for applications of on-line diagnosis in three pulp mills in South Africa. Real time process data from the pulp mills is fed into the model and a simulation is performed. Thereafter, the results from the simulation are compared to the actual measured data for a number of key variables. By comparing the simulation results to the real process data and following the trends of the deviations between the two, different types of faults and upsets can be detected in both the process and sensors. / KKS project:Use of physical models combined with statistical models for improved digester control

In the pulp production industry one potential problem is the production of gas from microbial activity in the storage tank. If left unchecked such gas production can in extreme cases lead to an explosion. To prevent any such event the current method of maintaining microbial activity in pulp plants is to use hazardous biocides. Such biocides can be expensive and dangerous to handle – therefore a safer and cheaper alternative would be preferred. This study aims to examine and evaluate two potential alternatives: Tannins extracted from trees with natural antibacterial properties and introduction of Lactobacillus plantarum to see if a more manageable bacteria can out-compete the bacteria already in the pulp. The results were measured by observing gas production in different trials where pulp from a nearby plant was mixed with different concentrations of tannins or Lactobacillus. The results showed that this strand of Lactobacillus plantarum had no effect on gas volume production while the pulp mixed with tannins did have some effect by lowering the amount of gas volume produced. However, the experiments with tannins and pulp showed no clear dose-response relationship which most likely is caused by varying quality and handling of the pulp used in the experiments. In summary this study shows that tannins can have an effect on the volume of gas produced by recycled paper pulp by lowering it – although not completely inhibiting it.

Cellulose is the most abundant organic polymer on Earth and a fascinating compound for a vast variety of applications. It is mostly received from wood, thus it is a renewable resource and a CO2 storing material. One of the most important cellulose products are pulp and paper. The major goal of this work was to obtain a material with a high amount of cellulose through a pulping process of wood. Therefore, it is necessary to separate the wood bers and to remove a component of wood, which is called lignin (deligni cation). The conventional way to delignify wood is the Kraft process that causes serval problems like contamination of lignin with sulfur and the emission of toxic volatile sulfur compounds. Hence, there are alternative processes without sulfur, such as the Acetosolv process. It uses simple chemicals like acetic acid and is easy to handle. After cutting a spruce tree (Picea abies L. Karst.), debarking and chipping, the wood chips were cooked in the laboratory. The research included the chemical analysis of the obtained pulp and the manufacturing and testing of paper sheets. The yield of pulp ranged widely due to the di erent parameters of the cooking. FT-IR and Raman spectroscopy were used to observe the decrease of aromatic substances (lignin) and the acetylation of the pulp. With the means of Design of Experiments and statistical analysis the most important factors were identi ed and a mathematical regression model was calculated. The manufactured paper sheets showed good mechanical properties and high transparency. Finally, the Acetosolv process could be considered as a contribution to the upcoming bio-based economy because, in addition to the cellulose bers, the industry would be capable of adding value utilization of the separated lignin. It could be one step to a more sustainable paper and pulp production.

The industrial sector in Sweden stands for 38 percent of the total energy use. Within these 38 percent the pulp and paper industry stand for about half of the energy use. Due to the extent of the energy use it is important that we do what we can to keep the energy usage as low as possible within our industries. In this bachelor thesis a case study is performed regarding a problem with a recovery boiler which belong to one of Stora Ensos pulp mills in a small town called Skutskär in Sweden. The problem with the recovery boiler is that it does not reach the temperature of the outgoing steam for which the soda boiler was designed, which causes the efficiency to suffer. The problem with the recovery boiler is not sustainable either in terms of energy use or economy. Recovery boiler 6 (RB6) as it is called is one of two recovery boilers belonging to the pulp mill. Both boilers are designed to produce high pressure steam at 56 bar and 450°C. The high-pressure steam produced goes through a back-pressure turbine where the pressure is lowered to the working pressure of the remaining factory while electricity is produced. Steam at a lower temperature results in lower enthalpy, which in turn will affect the electricity generation in the back-pressure turbine. The purpose of the study is to quantify the loss in electricity generation caused by the lack of steam temperature of RB6. As well as investigating the causes of the lack of heat transfer where the goal is to locate the problem area. A literature study was conducted regarding the efficiency of the recovery boiler, where much emphases was placed on the function of the superheater and the soot system. The superheater accounts for about 30 percent of all heat transfer in a recovery boiler and is directly crucial for reaching the final temperature of the steam. In the literature study, among other things, the design and fouling of superheater is studied to see that if affects the heater transfer. Further, the soot system effect on the heat transfer is also studied and it shows that the soot system has a greatly influence of the final heat transfer. The method used to conduct the study is primarily data analysis. The pulp mills internal analysis program WinMops is used in combined with Excel to analyze operational data. First, the magnitude of the problem was investigated by calculating the effect of RB6’s lack of steam temperature on the total enthalpy of the steam reaching the turbine. Calculations were made for electricity generation in normal cases and under the influence of RB6, where the difference was considered as lost electricity generation. Once the size of the problem was determined, the investigation of causes of heat transfer began, with the superheater coming into focus. The results of the case study show that RB6’s lack of steam temperature causes a loss of electricity production equivalent to 7 million SEK in a normal year and a year with a low electricity price, this amount to 3 million SEK. Whit regard to the second investigation, it is very likely that the superheater causes the temperature drop. However, the study shows that the superheater has no smaller heat transfer surface in relation to the other recovery boiler and that the heat transfer rate is also not deviant. The superheater shows a hint of fouling at the same time as the flow of soot steam is slightly lower on RB6, unlike the mill’s other recovery boiler. An interesting phenomenon that emerges in the study is that the tertiary air flow tends to have a greater effect on RB6 outgoing steam flow than expected. / Industrisektorn står för omkring 38 procent av Sveriges totala energianvändning. Av de 38 procenten står pappers- och massaindustrin för omkring hälften av all energianvändning. Eftersom industrin är en omfattande del gällande energianvändningen är det viktigt att åtgärder utförs för att hålla energianvändningen så låg som möjligt. I detta examensarbete utförs en fallstudie gällande ett problem med en sodapanna som tillhör Stora Ensos massabruk i Skutskär. Problematiken med sodapannan är att den inte når upp i den temperaturen på utgående ångan som sodapannan designades för vilket gör att verkningsgraden blir lidande. Problemet med sodapannan är inte hållbart både sett till energianvändning eller ekonomi. Sodapanna 6 (SP6) som den kallas är en av två sodapannor som tillhör massabruket. Båda sodapannorna är designade för att producera högtrycksånga vid 56 bar och 450°C. Högtrycksångan som produceras går via en mottrycksturbin där trycket sänks till arbetstrycken för resterande fabriken samtidigt som el produceras. Ånga vid lägre temperatur medför lägre entalpi vilket i sin tur kommer att påverka elproduktionen i motrycksturbin. Syftet med studien är att kvantifiera förlusten i elproduktion som den bristande ångtemperaturen av SP6 orsakar. Utöver det är syftet även att utreda orsaker till den bristande värmeöverföringen där målet är att lokalisera problemområdet. En litteraturstudie utfördes gällande effektivitet kring sodapannan varvid mycket tyngd lades på överhettarens samt sotningens funktion. Överhettaren står för omkring 30 procent av all värmeöverföring i en sodapanna och är direkt avgörande för att nå sluttemperaturen på ångan. I litteraturstudien studeras bland annat utformning och försmutsning av överhettaren för att se hur det påverkar värmeöverföringen. Vidare studeras sotningens påverkan på värmeöverföringen och även den påverkar i stor grad den slutgiltiga värmeöverföringen. Metoden som används för att genomföra studien är framförallt dataanalys. Massabrukets interna analyseringsprogram WinMops används tillsammans med Excel för att kunna analysera driftdata. Först utreddes storleken på problemet med hjälp av att beräkna hur stor påverkan SP6 bristande ångtemperatur har på den totala entalpin på ångan som når turbin. Beräkningar utfördes för elproduktion vid normalfall och vid påverkan av SP6 varvid skillnaden betraktades som den förlorade elproduktionen. När problemets storlek var fastställt började utredningen kring orsaker till bristande värmeöverföring varvid överhettaren hamnade i fokus. Studiens resultat visar att SP6 bristande ångtemperatur orsakar en elproduktionsförlust som motsvarar 7 miljoner kronor ett normalår och ett år med lågt elpris rör det sig om 3 miljoner kronor. Gällande den andra utredningen är det med stor sannolikhet överhettaren som orsakar temperaturfallet. Däremot visar studien att överhettaren inte har någon mindre värmeöverförande yta i förhållande till den andra sodapannan samt att värmeöverföringstalet är inte heller avvikande. Överhettaren visar en antydan på försmuttning samtidigt som sotångflödet är något lägre på SP6 till skillnad från brukets andra sodapanna. Intressant fenomen som dyker upp i studien är att tertiärluftflödet tenderar att ha en större påverkan på SP6 utgående ångflöde än förväntat.

Made available in DSpace on 2016-08-11T14:41:33Z (GMT). No. of bitstreams: 1 IsabelleAO_DISSERT.pdf: 1415862 bytes, checksum: 63b840c911ae8d800331e1f2a4329a7b (MD5) Previous issue date: 2015-02-25 / This thesis is part of a set of studies about the rural areas and family farming, considering its aspects in the economic structure, value addition, organizing group and insertion in the marketplace. There's always been missing a lack of public policies for the family farming, however, during these last ten years there have been issued for those lands significant amounts of funds, especially for small production structures. Although those structures constitute one of the most interesting and promising experiences to the countryside, they have worked in disabilities, and its economic dynamism has not happened. In this context, the main matter is how the supply chain of fruit pulp forms has made a set of initiatives that can build a promising new endogenous development format, but it has not been able enough to promote economic dynamism of the lands in Açu-Mossoró and in the countryside of Apodi (RN). By being aware about that, we tried and analyzed in a systematic way the fruit pulp production chain as an environment of innovation and production of new things, considering its role play in the diversification of the local economies, and in taking forward to the lands of Açu-Mossoró and in the countryside of Apodi (RN). As for the methodology to perform the data collecting we've chosen to use the primary data, which was consisted of a questioning in the units of fruit pulp production identified in the studied areas. As a result, the survey revealed that the fruit pulp chain is largely present in the countryside of Apodi than in Acu-Mossoró due to a larger number of production units, more diversified in the family farming, but besides that they have built a better social organization and consolidated group, which led them into their insertion into different markets. However, deficiencies have been identified, such as the lack of trade certification which limits them in the market insertion. This survey found that the lack of infrastructure is related to the lack of credit, technical and technology assistance, leading the farmers to develop their own new strategies and create their own new policies to try and access their join into the markets / Essa dissertação se insere no conjunto de estudos sobre o meio rural e a agricultura familiar, considerando aspectos relacionados com sua estruturação econômica, agregação de valor, organização coletiva e inserção em mercados. Para a agricultura familiar sempre houve carência de políticas públicas, no entanto, nos últimos dez anos têm sido destinados somas significativas de recursos financeiros para os territórios, especialmente para estruturas produtivas de pequeno porte. Apesar dessas estruturas constituírem uma das experiências mais interessantes e promissoras para o meio rural, elas têm funcionado com deficiência, e a dinamização econômica não tem acontecido. Neste contexto, a questão central é como a cadeia produtiva de Polpa de Frutas forma um conjunto de iniciativas que constrói um novo e promissor formato de desenvolvimento endógeno, porém não tem sido capaz o suficiente para promover a dinamização econômica dos territórios Açu-Mossoró e Sertão do Apodi (RN)? Em face disso, buscou-se analisar, de forma sistêmica, a cadeia produtiva de Polpa de Frutas como ambiente de inovação e produção de novidades, considerando o seu papel na diversificação das economias locais, e na dinamização dos territórios Açu-Mossoró e Sertão do Apodi (RN). Quanto à metodologia para efetuar a coleta de dados optou-se pelos dados primários, que consistiu na aplicação de questionários nas unidades de produção de Polpa de Frutas identificadas nos territórios estudados. Como resultados, a pesquisa revelou que a cadeia de polpa de frutas está mais presente no Território Sertão do Apodi do que no Açu-Mossoró, devido a um número maior de unidades produtivas, de uma agricultura familiar mais diversificada, como também possuir uma organização social e coletiva mais consolidada, o que propiciou a inserção em mercados diferenciados. Porém, foram detectadas deficiências, a exemplo da falta de certificação o que limita a inserção em mercados. A pesquisa apontou que a carência de infraestrutura está relacionada com a falta de crédito, assistência técnica e tecnologia, o que leva os agricultores familiares a elaborar estratégias de inovação e da criação de novidades para acessar políticas e se inserir em mercados

Submitted by Guilherme Marini Perpétua null (geomarini@yahoo.com.br) on 2016-11-29T18:54:10Z No. of bitstreams: 1 Tese_Guilherme Marini Perpetua_Final.pdf: 7304127 bytes, checksum: 19caede8e6f62b2963332efe102acb12 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-02T14:58:47Z (GMT) No. of bitstreams: 1 perpetua_gm_dr_prud.pdf: 7304127 bytes, checksum: 19caede8e6f62b2963332efe102acb12 (MD5) / Made available in DSpace on 2016-12-02T14:58:47Z (GMT). No. of bitstreams: 1 perpetua_gm_dr_prud.pdf: 7304127 bytes, checksum: 19caede8e6f62b2963332efe102acb12 (MD5) Previous issue date: 2016-11-16 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho teve como objetivo compreender o processo de territorialização recente da produção de celulose associada ao monocultivo arbóreo (eucalipto) no Brasil, com ênfase em suas implicações para a segurança e a saúde dos trabalhadores(as). Com este intuito, foram analisados os mais novos megaempreendimentos do segmento no país, localizados em diferentes espaços regionais (Extremo Sul da Bahia, Oeste do Maranhão e Nordeste de Mato Grosso do Sul), os quais compuseram o recorte empírico da pesquisa. Em termos metodológicos, a pesquisa buscou combinar o uso de procedimentos quantitativos (levantamento e análise de dados secundários) àqueles de natureza qualitativa (análise documental, diário de campo, entrevistas semiestruturadas), de modo a considerar os aspectos estruturais sem deixar de enfocar o papel exercido pelos sujeitos sociais concretos. Os resultados alcançados permitem defender a tese de que, em função de suas características estruturais inerentes e nos moldes atuais, a produção de celulose só pode se dar na exata medida em que for capaz de se apropriar e exercer controle vertical e autoritário sobre territórios contíguos e de grande extensão, de modo a fruir de maneira monopolista dos recursos existentes. Para tanto, o capital tem lançado mão de uma estratégia deliberada e sistemática composta por um conjunto de táticas que, observadas à luz do materialismo dialético, revelam a combinação entre distintas formas de acumulação (primitiva, por espoliação e ampliada), dando corpo ao que chamamos de pilhagem territorial. Além da escassa geração de empregos mal remunerados e instáveis, para os trabalhadores o resultado não poderiam ser outro senão um trabalho visceralmente precário e degradante, contraditoriamente e até certa medida adequado às exigências de mercado (certificações internacionais) conformadoras das políticas internas de saúde e segurança do trabalho das grandes corporações do segmento. Tudo isso, no período analisado, foi ampla e generosamente assegurado de diversas formas (concessão de financiamentos, incentivos fiscais, investimentos em infraestrutura, flexibilização da legislação ambiental etc.) pelo modelo novo-desenvolvimentista fundado num verdadeiro pacto conciliatório de classes e adotado pelos governos do Partido dos Trabalhadores. / This study aimed to understand the recent territorialization process of pulp production associated to tree monoculture (eucalyptus) in Brazil, with emphasis on the implications for the safety and health of workers. To this end, the newest mega-enterprises of the segment in the country were analyzed, located in different regional areas (southernmost Bahia, West Maranhao and Northeast of Mato Grosso do Sul), which formed the empirical object of the research. In terms of methodology, the research sought to combine the use of quantitative procedures (survey and analysis of secondary data) to those of a qualitative nature (document analysis, field diary, semi-structured interviews), in order to consider the structural aspects while focusing on the role of concrete social subjects. The results obtained allow to make the case that, due to their inherent structural characteristics and current patterns, pulp production can only take place on the exact extent that it is able to appropriate and exert vertical and authoritarian control over contiguous territory and large extension, in order to enjoy the existing resources in a monopolist mode. Thus, the capital has made use of a deliberate and systematic strategy consisting of a set of tactics that, seen in the light of dialectical materialism, reveal the combination of different forms of accumulation (primitive by dispossession and expanded), forming what we called territorial plunder. In addition to the low generation of low-paid and unstable jobs to workers the result could not be other than a viscerally precarious and degrading, contradictory and even to a certain extent appropriate to market demands (international certifications) conforming internal health and safety policies of work of the large corporations of the segment. All this, in the analyzed period, was widely and generously provided in various forms (funding grant, tax incentives, infrastructure investments, easing of environmental legislation etc.) by the new development model based on a true conciliatory pact of classes and adopted by governments of the Workers' Party. / Este estudio tuvo como objetivo comprender el reciente proceso de territorialización de la producción de pulpa asociado con monocultivos de árboles (eucaliptos) en Brasil, con énfasis en sus implicaciones para la seguridad y salud de los trabajadores. Con este fin, se analizaron las mega-empresas más recientes del segmento en el país, que se encuentra en diferentes áreas regionales (extremo sur de Bahia, oeste de Maranhão y noreste de Mato Grosso do Sul), que formaron el objeto empírico de la investigación. En cuanto a la metodología, la investigación trató de combinar el uso de procedimientos cuantitativos (encuestas y análisis de datos secundarios) a los de carácter cualitativo (análisis de documentos, diario de campo, entrevistas semiestructuradas), a fin de considerar los aspectos estructurales mientras se centra en el papel ejercido por los sujetos sociales concretos. Los resultados obtenidos permiten defender la tesis de que, debido a sus características estructurales inherentes y los patrones actuales, la producción de pasta sólo puede ocurrir a la medida exacta que es capaz de apropiarse y ejercer el control vertical y autoritario sobre territorios contiguos y de gran extensión, con el fin de disfrutar de manera monopolista de los recursos existentes. De este modo, el capital ha usado una estrategia deliberada y sistemática compuesta de un conjunto de tácticas que, visto a la luz del materialismo dialéctico, revelan la combinación de diferentes formas de acumulación (primitivas por desposesión y ampliada), dando cuerpo a lo llamamos despojo territorial. Además de la baja generación de puestos de trabajo con salarios bajos e inestables a los trabajadores, el resultado no podría ser otro que un trabajo visceralmente precario y degradante, contradictoriamente y hasta cierto punto adecuado a los requisitos del mercado (certificaciones internacionales) conformadoras de las políticas de salud y seguridad del trabajo de las grandes corporaciones del segmento. Todo esto, en el período analizado, fue ampliamente y generosamente verificado de diversas formas (subvenciones, incentivos fiscales, inversiones en infraestructuras, flexibilización de la legislación ambiental, etc.) por el nuevo modelo de desarrollo basado en un verdadero pacto de conciliación de clases y adoptado por los gobiernos del Partido de los Trabajadores. / FAPESP: 2013/04638-0