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Swedish hardwood is today used in the energy, pulp and mechanical hardwood industries. Only very small volumes of Swedish hardwood are, however, consumed by the mechanical industry that normally pays the highest timber price. The smallness of the volumes used for mechanical refinement is a result both of forestry not focusing on the production of hardwood for these uses, and of the fact that the mechanical hardwood industry, particularly the sawing industry, is not designed to process the existing raw material in an optimal manner. This thesis discusses the possibilities of improving the conditions for the mechanical refinement of hardwood. The aim of the work has been to investigate the possibilities of developing products and methods for processing of Swedish hardwood. The thesis proposes a new manufacturing system for Swedish hardwood to better utilize the inherent properties of the wood material. The system is based on the so-called PrimWood Method and the star-sawing concept. Compared to normally sawn wood, the sawing concept utilizes the raw material more efficiently with regard to volume yield, and increases the distance between knots in the sawn wood. The material produced has vertical annual rings which give the wood smaller movements as a result of moisture variations and a different textural appearance. Using the PrimWood Method for hardwood would make it possible to more closely match customer requirements regarding hardwood products. Since Swedish hardwood is nowadays mainly used indoors, a possible way of expanding the market would be to increase the outdoor use of the material. Here the durability is of great importance, and one important factor is then the capillary characteristics of the material. The thesis therefore focuses on the characterisation of the capillarity in wood for the future improvement of its durability. It is shown that with the material produced by the proposed manufacturing system, i.e. wood with vertical annual rings, the possibility of using hardwood outdoors increases, because the susceptibility to cracking decreases.

The manufacturing process of a photovoltaic Si wafer comprises of first a high temperature heating process to produce a Si ingot from polycrystalline Silicon, which is then cut into bricks and subsequently sawn into wafers using a wire saw. These processes create residual stresses both from the thermal gradient induced by solidification and from either the rolling-indenting or scratching-indenting processes caused by the type of wire saw used. The objective of this research is to study silicon wafer residual stress as a result of the typical industry manufacturing processes and by doing so, better understand the mechanical properties that lead to increased fracture. This thesis aims to quantify the amount of residual stress generated by the solidification/thermal gradient produced during the casting of Si ingots separately from the residual stress generated by the wire sawing process. Samples from industry are used to compare the effects of the manufacturing processes on residual stress in multi-crystalline silicon (mc-Si) wafers including the effects of fixed abrasive diamond wire sawing (DWS) vs. loose abrasive (LAWS) slurry wire sawing used in the wafering process. Near-infrared birefringence polariscopy and polarized micro-Raman spectroscopy are used to study wafer residual stresses within grains and at grain boundaries in mc-Si as a function of etch-depth. While near-infrared birefringence polariscopy allows for the measurement of full-field maximum shear stress, micro-Raman spectroscopy provides decomposition of the stress tensor into both principal and shear in-plane stress components. Consequently, regions of high tensile stress, which are detrimental to the mechanical integrity of the wafer, can be easily identified. In addition to the mechanical characterization, the residual stress produced by the thermal gradient/solidification process for multi-crystalline Si wafers was also correlated to electrical performance of mc-Si wafers using photoluminescence.

The harvesting of Mozambique tropical hardwood species is considerable higher than the natural regrowth in the forest and the stock is decreasing drastically. Therefore, it is important to improve the material recovery when the wood is refined (i.e., in sawing and further refinement to products such as joineries, furniture etc.) to reduce the waste and to re-utilize efficiently the by-products to increase the added value. The wood processing industry is an important means to boost the industries in the rural areas and also to generate incomes for the local communities by creating jobs and business opportunities. The majority of the logging that can be used for sawmilling in Mozambique is exported as roundwood due to the inability of companies to meet the product standards set for export and to generate profit. The lack of capabilities of the local sawmills to generate profit, also foments the illegal logging because of the higher price of roundwood for export which contributes to increase the number of unlicensed individuals in harvesting. This threatens the law enforcement and thus the degradation of the local wood industry. An alternative to increase the profit and empower the local community could be to export more refined wood products such as sawn timber, parquet, and veneer instead of the roundwood. The objective of the work was to investigate alternative sawing strategies of tropical hardwood species that could increase the profitability of the Mozambique wood industry in general and at sawmill in particular. The subject was approached using a database of virtual logs and together with a sawing simulator. The thesis has two main focus areas: (1) creating the log database with the corresponding algorithms for sawing simulation, and (2) investigations of alternative sawing strategies. The first focus was to build the database of surface-scanned logs and develop the algorithm for the saw simulation. The results are a database of 15 logs models describing the logs outer shape in which 10 jambirre (Millettia stuhlmannii Taub.) and 5 umbila (Pterocarpus angolensis DC.), and the algorithm for the sawing simulation. The algorithm use “brute force” i.e., determines all volume yields of sawn timber from the combination of all settings of log-positioning parameters (offset, skew and rotation) and selects the maximum value of volume yield. From simulation, using three sawing patterns (cant-sawing, through-and-through sawing and square-sawing) combined with two positioning parameters (offset and rotation) it was found that the sawing pattern has great impact on volume yield and that the square-sawing gave higher yield followed by through-and-through sawing pattern. The second focus was on alternative sawing strategies; having in mind that the optimal volume yield is achieved by aid of computerized production systems and that these resources are not yet in use in Mozambique. Hence, the objective was to find the positioning parameters that can be set manually and improve the volume yield. The result have shown that the rotation is the most affecting parameter followed by offset and skew, and that the volume yield can decrease by between 7.7% and 12.5% from the optimal positioning when the logs are manually positioned with the knowledge about the optimal log position. In another study, using crook-up or horns-down positioning as alternative to the optimal positioning, the volume yield decreases by between 10% and 13% from the optimal positioning. By using bucked logs , the optimal volume yield increased by between 8% and 13% in relation to full lengths logs, and the volume yield of bucked logs when using crook up positioning decreases 2% in relation to optimal positioning of full length logs. It is concluded that there is an unexploited value potential in the wood chain which can be reached using alternative positioning and modern measurement techniques and that the grading of wood will facilitate and improve the sawing process.

O presente trabalho apresenta uma revisão bibliográfica sobre o processo de serramento por serra de fita, abordando fatores relativos ao desempenho de corte nas diversas operações deste processo. Na seqüência, apresentam-se os seguintes estudos específicos: características da madeira que exercem influência nas operações de serramento por serra de fita: o processo de serramento e; ferramentas de corte. A fim de se verificar os aspectos teóricos especificados na literatura para adequação do processo de serramento, efetuou-se um estudo de caso em uma serraria, usinando-se a espécie de madeira Pinus oocarpa em operação de desdobro com serra de fita vertical. Neste estudo, realizou-se a medição da potência consumida durante o corte com aquisição de dados em tempo real, a qual possibilitou calcular a potência de corte média. / The present work shows a bibliographical review on band sawing, in respect to the factors related to cutting performance during the several operations of such process. Moreover, the following studies are presented: wood characteristics influencing the band sawing; sawing process itself; and cutting tools. In order to check the theorical aspects encountered in the literature to adequate the sawing process, a case study in a sawmill plant has been carried out. Pinus oocarpa wood species has been machied by unfolding using a vertical bandsaw. The consumed power during the cutting process was measured by a data acquisition system in real time, what allowed the calculation of the average cutting power.

Com a utilização de filtros percoladores aeróbios, procurou-se promover a remoção de nitrogênio amoniacal do esgoto sanitário efluente de reator anaeróbio compartimentado, através do processo de nitrificação. O trabalho foi desenvolvido em duas fases; na primeira foi realizada a preparação da serragem de couro utilizando-se peneiramento e lavagens e a seguir iniciou-se a aplicação do esgoto sanitário em quatro filtros percoladores. Os filtros F1 e F2 foram operados com a mesma taxa de aplicação (1,91 'M POT.3'/'M POT.2'.dia) e diferentes meios suportes, sendo brita e serragem de couro do tipo wet blue respectivamente. Os filtros F3 e F4 foram preenchidos com serragem de couro e operaram com taxa de aplicação hidráulica de 4,00 e 6,00 'M POT.3'/'M POT.2'.dia . O filtro F3 apresentou melhores eficiências de remoção para todos os parâmetros, com eficiência média de remoção de NTK, 'N'-'NH IND.3' e DQO de 71%; sendo que a partir do sexagésimo quarto dia, esse filtro passou a apresentar 100% de remoção de NTK e 'N'-'NH IND.3'. Os filtros F1 e F2 podem ter tido problemas com a aeração, já que foram operados com menores taxas de aplicação hidráulica e deveriam apresentar melhores resultados. O filtro F4 apresentou baixas eficiências de remoção, provavelmente devido a maior taxa de aplicação hidráulica. / The aim of the work is to promote the ammoniacal nitrogen removal from anaerobic baffed reactor effluent using aerobic trickling filters, through the nitrification process. The research was developed in two phases; firstly the leather sawing was prepared through sieving and washing, later the domestic sewage was applied into four tricking filters. The F1 and F2 filters were operated with the same hydraulic loading (1,91 'M POT.3'/'M POT.2'.day) and different filter packing. For the F1 filter was used rock and for the F2 wet blue leather sawing. The F3 and F4 filters were filled with leather sawing and operated in a hydraulic loading of 4,00 and 6,00 'M POT.3'/'M POT.2'.day respectively. The F3 filter presented better removal efficiencies for all the parameters, with 70% of average removal efficiency of KTN (Kjeldahl Total Nitrogen), 'NH IND.3'-'N' (ammoniacal nitrogen) and COD (Chemical Oxygen Demand). From the 49th day on, this filter presented 100% of removal efficiency of KTN and 'NH IND.3'-'N'. The F1 and F2 filter were supposed to present better results due to the lower hydraulic loading, but it did not happen, probably because the aeration was not enough. The F4 filter presented low removal efficiency, possibly due to the higher hydraulic loading.

O desdobramento de blocos de granitos, em teares multilâminas, é uma das mais complexas operações da indústria da pedra. A qualidade das superfícies das chapas obtidas no processo de serragem (rugosidade) determina o tempo e os insumos gastos nas operações posteriores de polimento, implicando diretamente no custo final. Embora o Brasil seja um dos maiores produtores mundiais de granitos ornamentais (quatro milhões de 'M POT.2'/mês de placas), surpreendentemente, não se têm na literatura científica trabalhos que dão o devido destaque às propriedades intrínsecas dos granitos no processo de serragem. A presente pesquisa tem como objetivo principal correlacionar parâmetros petrográficos com as características físicas e mecânicas de granitos, dando ênfase ao estudo da influência da mineralogia e da anisotropia textural/estrutural, com vistas à melhor orientação desta etapa industrial. Foram escolhidos tipos de granito consagrados comercialmente e acompanhados os desdobramentos de blocos para medidas diretas da rugosidade das superfícies serradas com o auxílio de um equipamento especialmente construído para esta finalidade. Os resultados mostraram que os aspectos texturais (granulação, arranjo, imbricação, grau de microfissuramento) e de alteração dos minerais são os responsáveis pelas diferenças na rugosidade das chapas e na velocidade de processamento / The sawing of granites blocks using multiblade gangsaws is one of the most complex operations in the stone processing industry. The slab surface quality (roughness) obtained after the sawing process determines the time and the inputs required in subsequent polishing operations and thus has a direct implication on the final product cost. Although Brazil is one of the largest world producers of ornamental granites (four million 'M POT.2'/month of slabs), it is surprising to note that there are very little or no scientific literature works available that address major aspects of the intrinsic properties of granites and their role during the sawing process. The present research has the major objective of correlating petrographic parameters with physical and mechanical characteristics of granites with a major emphasis on the role played by mineralogy and textural/structural anisotropy focusing mainly on how to obtain the best orientation during this industrial stage. The samples used are the most widely used granite of high commercial value in Brazil. The sawing process was monitored and subsequent direct measures of the roughness of the sawed surfaces carried out using an equipment specially built for this purpose. The results obtained show that textural (granulation, arrangement, imbrication, degree of microcracking) and alteration aspects of the minerals are responsible for the observed differences in slab roughness and processing speed

A produção de aço necessita de etapas e gera resíduo, dentre eles tem-se a escória de aciaria. No estado do Espírito Santo, Brasil, a mineração de granito é uma das principais atividades econômicas gerando o resíduo de serragem de granito. Nesta pesquisa, busca-se o reaproveitamento destes resíduos, de modo a minimizar possíveis problemas ambientais, apontar a viabilidade técnica do seu uso e reciclá-los por meio de utilização na produção de cimento. Alguns dos principais componentes das escórias de aciaria, tais como, o óxido de cálcio, óxido de magnésio e o ferro metálico sofrem transformações químicas em presença de umidade, que provocam expansão volumétrica da escória. Este fenômeno aliado a reatividade da escória tem dificultado sua utilização. Este trabalho é uma contribuição ao estudo do aproveitamento da escória de aciaria, que passa a ser chamada de ss (steel slag) e do resíduo da serragem de granito, que passa a ser chamado gsw (granite sawing waste), oriundo da extração de granito. Os resíduos estão disponíveis em quantidades nos pátios das siderúrgicas e nas áreas de mineração do granito, respectivamente. Para o reaproveitamento foi realizada a caracterização física, química e mineralógica dos resíduos. Diferentes dosagens de misturas foram produzidas com ss e gsw de forma a permitir avaliação das propriedades obtidas nestas misturas visando sua utilização na produção de cimento. Desenvolveu-se misturas nas quais busca-se a basicidade na escória de aciaria, compreendida entre 4 e 5, para valores próximos ao da escória de alto-forno, na faixa de 0,9 a 1,5 cuja utilização na produção de cimento já está normatizada desde 1991 (NBR 5735, ABNT 1991). Misturas com basicidade entre 0,9 a 4 foram pesquisadas e selecionou-se a mistura com basicidade 1,2 para ser utilizada na produção de cimento. Ao longo da pesquisa foi necessária a produção de 3(três) tipos de cimento até se equacionarem os problemas técnicos e operacionais que surgiram ao longo da mesma. Suas propriedades foram medidas e comparadas com as do cimento contendo escória de alto-forno. As análises dos resultados obtidos para o cimento produzido com a mistura são apresentadas e indicam o potencial de utilização dos resíduos como elementos de adição ao cimento apesar da heterogeneidade dos materiais. / Steel making requires production stages and generates waste, such as steel slag. In the State of Espirito Santo, Brazil, granite mining is one of the main economic activities, wich generates granite sawing waste. This study aims at reusing these two types waste in order to minimize possible environmental problems; point out the technical feasibility of their use; and recycle them by using in cement. Some of the main components of steel slag, such as calcium oxide, oxides, and metallic iron undergo chemical transformations in the presence of humidity, wich cause slag volume expansion. This phenomenon, combined with slag reactivity, has made its use difficult. This study is a contribution to the study on reusing steel slag (ss) and granite sawing waste (gsw) deriving from granite mining. These types of waste are available in large amounts in the yards of steelmaking plants and granite mining areas, respectively. In order to reuse waste, physical, chemical and mineralogical characterizations were carried out. Different mix proportions were made with ss and gsw so as to allow the evaluation of the properties obtained from these mix designs, aiming at their use in cement production. The tests sought steel slag basicity between 4 and 5, for values close to those of blast-furnace slag ranging from 0.9 to 1.5, whose use in cement production has been standardized since 1991 ( NBR 5735, ABNT 1991). Mix designes with basicity between 0,9 and 4 were studied, and a mix with basicity 1.2 was chosen to be used in cement production. Throughout the investigation, 3 types of cement needed to be made until all the technical and operational problems arising were solved. Their properties were measured and compared to those of blast-furnace cement. The analyses of the achieved results for the cement made with that mix are presented and they show the potential use of these types of waste as admixture elements to cement, despite material heterogeneity.

Visando determinar os valores ótimos para o processo de serramento de anéis bobinados de filme metalizado ultrafino de alumínio com dielétrico de poliéster a partir das condições atuais do processo de fabricação de capacitores pela empresa Epcos do Brasil, realizou-se a avaliação de diferentes tipos de serras circulares variando-se a velocidade de rotação (n) e o tempo de corte (tc). Desenvolvido projeto de experimento desses três fatores a fim de obter o resultado das interações entre eles quanto à resistência de isolamento (Riso) das peças cortadas. A serra de 160 dentes de metal-duro com revestimento de filme de carbono tipo diamante (DLC) apresentou os melhores resultados quanto à “Riso” acima de 0,378 G e quanto ao número de peças com valor abaixo deste. Constatou-se que “n” não influencia significativamente para a distribuição de “Riso”; porém, gera menos peças abaixo do especificado. Já “tc” não influencia significativamente o processo. Quanto ao tipo de dente, o perfil reto obteve melhor resultado para lâminas de serra com 80 dentes e perfil curvo para lâminas com 160 dentes. Já a espessura da lâmina não influenciou de forma expressiva o processo. A lâmina de aço-rápido apresentou adesão de alumínio na lateral do corpo da serra e, consequentemente, adesão de material na superfície de corte. As lâminas de metal-duro sem revestimento apresentaram falhas no filme metalizado por causa do atrito gerado entre a superfície de corte e a lateral da lâmina; esse inconveniente é eliminado quando ela é revestida com filme DLC apresentando melhorias quanto à “Riso” das peças para “n” menores. Também houve adesão de alumínio na parte inferior do dente devido a uma delaminação da camada de filme DLC. / In order to determine the optimal values for the sawing process of wound rings of metalized ultra-thin film with dielectric of polyester from current conditions of capacitor manufacturing process by Epcos company in Brazil, it was performed the evaluation of different types of circular saws varying the rotational speed (n) and the cutting time (tc). Developed experiment design methodology for these three factors in order to get the result of the interactions between them regarding to the insulation resistance (Riso) of cut parts. Through the analysis of the main effects, the cemented carbide saw with 160 teeth and diamond-like carbon (DLC) film coating showed the best results in terms of "Riso" above 0,378 G and regarding to the number of parts with value below the specified. It was found that "n" does not influence significantly the distribution of "Riso"; however, generates fewer parts below the specified. Now "tc" does not significantly influence the process. Regarding the tooth type, straight profile obtained better results for saw blades with 80 teeth and curved profile for blades with 160 teeth. However the thickness of the blade did not influence significantly the process. The high speed steel blade presented adhesion of aluminum on the side of the saw body and, consequently, adhesion of material on the cutting surface. The cemented carbide blades uncoated presented failures on metalized film because of the friction generated between the cutting surface and the side of the blade; this drawback is eliminated when it is coated with DLC film presenting improvements to the parts "Riso" for lower "n". There was also aluminum adhesion on the bottom of the tooth due to a delamination of the DLC film layer.

Visando determinar os valores ótimos para o processo de serramento de anéis bobinados de filme metalizado ultrafino de alumínio com dielétrico de poliéster a partir das condições atuais do processo de fabricação de capacitores pela empresa Epcos do Brasil, realizou-se a avaliação de diferentes tipos de serras circulares variando-se a velocidade de rotação (n) e o tempo de corte (tc). Desenvolvido projeto de experimento desses três fatores a fim de obter o resultado das interações entre eles quanto à resistência de isolamento (Riso) das peças cortadas. A serra de 160 dentes de metal-duro com revestimento de filme de carbono tipo diamante (DLC) apresentou os melhores resultados quanto à “Riso” acima de 0,378 G e quanto ao número de peças com valor abaixo deste. Constatou-se que “n” não influencia significativamente para a distribuição de “Riso”; porém, gera menos peças abaixo do especificado. Já “tc” não influencia significativamente o processo. Quanto ao tipo de dente, o perfil reto obteve melhor resultado para lâminas de serra com 80 dentes e perfil curvo para lâminas com 160 dentes. Já a espessura da lâmina não influenciou de forma expressiva o processo. A lâmina de aço-rápido apresentou adesão de alumínio na lateral do corpo da serra e, consequentemente, adesão de material na superfície de corte. As lâminas de metal-duro sem revestimento apresentaram falhas no filme metalizado por causa do atrito gerado entre a superfície de corte e a lateral da lâmina; esse inconveniente é eliminado quando ela é revestida com filme DLC apresentando melhorias quanto à “Riso” das peças para “n” menores. Também houve adesão de alumínio na parte inferior do dente devido a uma delaminação da camada de filme DLC. / In order to determine the optimal values for the sawing process of wound rings of metalized ultra-thin film with dielectric of polyester from current conditions of capacitor manufacturing process by Epcos company in Brazil, it was performed the evaluation of different types of circular saws varying the rotational speed (n) and the cutting time (tc). Developed experiment design methodology for these three factors in order to get the result of the interactions between them regarding to the insulation resistance (Riso) of cut parts. Through the analysis of the main effects, the cemented carbide saw with 160 teeth and diamond-like carbon (DLC) film coating showed the best results in terms of "Riso" above 0,378 G and regarding to the number of parts with value below the specified. It was found that "n" does not influence significantly the distribution of "Riso"; however, generates fewer parts below the specified. Now "tc" does not significantly influence the process. Regarding the tooth type, straight profile obtained better results for saw blades with 80 teeth and curved profile for blades with 160 teeth. However the thickness of the blade did not influence significantly the process. The high speed steel blade presented adhesion of aluminum on the side of the saw body and, consequently, adhesion of material on the cutting surface. The cemented carbide blades uncoated presented failures on metalized film because of the friction generated between the cutting surface and the side of the blade; this drawback is eliminated when it is coated with DLC film presenting improvements to the parts "Riso" for lower "n". There was also aluminum adhesion on the bottom of the tooth due to a delamination of the DLC film layer.