Accounting for in-woods carbon storage in carbon accounting systems may be insufficient when substantial amounts of sequestered carbon are harvested and converted to long-lived wood products and landfills. The potential for offsetting greenhouse gas (GHG) emissions by storing carbon in managed loblolly pine forests in the southern United States was projected over the next half-century, both in terms of in-woods aboveground carbon pools and harvested products, including wood used for energy production. A region-wide data set from the Forest Inventory Analysis (FIA) program of USDA Forest Service was used to set initial conditions and estimate model parameters for projecting management activities including plantation area, age distributions of thinning, and clearcut harvest on an annual timestep. The stand-level growth and yield model FASTLOB was linked to the FIA data to project growth rates and annual harvest volumes of sawtimber and pulpwood for the projection period, accounting for annual timber harvests and the life cycles of wood products. In addition to baseline management practices, projections were made for scenarios that assumed increasing management intensities including the use of chemical fertilizers and herbicides and genetically-improved growing stock. Present-day carbon storage in well-managed southern pine plantations averaged 30.54 Mgâ ha⁻¹ (± 2.54%) for aboveground carbon. Over a 50-year projection, annual wood production was 62.1 and 45.9 million green metric tons from pulpwood and sawtimber yield, with roughly one-fourth of the green weight being carbon. Baseline projections showed aboveground carbon pools of up to 341 million metric tons being maintained over the next 50 years, with 93% in aboveground live trees and 7% in coarse woody debris (CWD). The carbon storage in wood products increased steadily over the half-century projection and showed no sign of leveling off, while the storage in plantations was found to remain constant or increase slightly over time. An additional 11 million metric tons of harvested carbon was used for energy per year on average, equivalent to 25% of annual forest-products-industry renewable energy use in U.S.A. Intensified forest management practices showed the potential to increase as much as 30% total carbon stored in in-woods and harvested-wood-products pools, with potential increases up to 40% in energy offsets above the baseline scenario. Reducing management intensity greatly increased in-woods carbon storage potential, but eliminated the wood-products carbon sink. / Ph. D.

An equation for predicting the strength of wood beams with tension end notches (TEN) was derived using a critical fillet hoop stress (CFHS) theory. The equation is a simplified description of the results of hundreds of finite element (FE) analyses of TEN beams with varied geometries (total of 690 configurations). It accounts for the effects of loading type and beam and notch geometry variables, such as beam height, fractional notch depth, radius and notch location. The effect of span-to-depth ratio is implicitly incorporated in the formulation of the model. Notched beam strength is represented by a material parameter, K, which was found to be related to specific gravity. A simple equation for predicting K from specific gravity was derived from experimental results. The CFHS equation is applicable to both filleted and sharp-cornered notches. An effective radius, R, which models the effect of a sharp-cornered notch, was determined and confirmed for two wood materials. A method of determining R, for other materials was established. The CFHS equation was compared with other models and notch equations currently recommended in design codes and significant differences were noted. Chief among them is the sensitivity of notched beam strength to notch location (or the ratio M/V). This is not currently considered by “notch factor"-based design equations. Stiffness of TEN wood beams was experimentally found to be influenced by fractional notch depth and notch location, M/V. The effect of end notching on beam stiffness has not been seriously addressed before and theoretical analysis does not predict the reduction. / Master of Science

Since the emergence and the subsequent evolution of lean manufacturing concepts, numerous enterprises of different scale and specialties have adopted lean tools and techniques in their facilities with varying success. In general, lean manufacturing related studies have been conducted on large manufacturing firms, such as the automotive industry. Yet, lean manufacturing tools and techniques are also suited for small enterprises. Thus, the main concern of this study is to investigate the success of set-up time reduction efforts (one of the steps needed to achieve 'one-piece flow') in secondary wood products manufacturing facilities on four woodworking machines (moulder, shaper, table saw, and band saw) based on firm size. The first objective of this research is to explore the results of the implementation of set-up time reduction efforts on selected woodworking machines in enterprises of varying size. It is assumed that company size is a major factor influencing the rate of set-up time improvements. To that end, the first hypothesis, which states that 'Small firms are less successful in reducing set-up time through set-up time reduction efforts than are large firms,' has been developed and supportive questions have been corresponding created. While statistical testing of the hypotheses created for this is not possible due to the limited number of participants, speculations about the possible outcome can be made. Thus, for hypothesis one, the data obtained does not show any sign of a relationship between a firm size and the success rate of set-up time reduction efforts. The second objective of this study is to investigate how a firm's productivity is affected by set-up time reduction efforts as related to firm size. With regards to some of the weaknesses of typical small manufacturing firms (e.g. having limited budget and resources, intuitive management strategies including lack of strategic planning), large firms, by and large, are expected to be more successful in increasing productivity through set-up time reduction. To that end, the goal is to investigate results of the set-up time reduction efforts in terms of productivity improvement in manufacturing facilities. With this in mind, the second hypothesis was proposed, which reads 'Small firms achieve lower productivity gains through set-up time reduction than do large firms.' For the second hypothesis, while no conclusive proof can be offered, no sign of a relationship between firm size and productivity gain through set-up time reduction could be found. Another objective of this study is to explore the success rate of set-up time activities on the four types of woodworking machines in industry facilities considering the training activities provided by manufacturers. The aim is to compare set-up time improvement performance of manufacturers between enterprises which trained their workers/operators and enterprises which did not train their employees. To understand the relationship between the scale of firms (and/or facilities) and training activities to improve set-ups, the third hypothesis, which reads 'Small firms are less concerned with set-up time reduction through training than are large firms,' has been developed. For the third hypothesis, while testing is not possible, it appears that there is no relationship between firm size and the level of concern for set-up time reduction through training activities. The final objective of this research is to investigate whether the secondary wood manufacturing firms studied experienced a bottleneck in their production due to the long set-up actions of machines. In order to accomplish this objective, the final hypothesis, 'In both, large and small firms, bottlenecks occur at machines with high set-up times,' has been developed. The final hypothesis cannot be accepted or rejected due to the limited number of responses obtained, set-up time was a frequently indicated explanation for the occurrence of production bottlenecks in secondary wood products manufacturing firms. / Master of Science

A cadeia produtiva da madeira gera uma grande quantidade de resíduos sólidos em todos os seus níveis, desde o plantio até as subsequentes etapas de produção. Esses resíduos recebem destinos diferentes de acordo com fatores ligados à regionalidades, existência de mercado para absorvê-los, quantidade gerada, porte da empresa ou estabelecimento que os gera, e outras variáveis; existem no cenário nacional, duas tendências observadas na pesquisa para lidar com os resíduos de madeira: uma delas é o descarte ao ar livre ou a queima sem fins energéticos; e outra tendência é a queima para produção de energia. Apesar de se tratar de uma alternativa bastante usual, a queima desse material libera o carbono de volta para a atmosfera e não se adequa a ordem de prioridade de gestão de resíduos sólidos estabelecida por lei (12.305/2010), além de encerrar o ciclo econômico da madeira, que poderia ainda ser reciclada e comercializada sob a forma de novos produtos. Com isso, decidiu-se utilizar a maravalha, que é um dos resíduos mais comuns do processamento da madeira, como base para a produção de painéis de partículas. Além disso, suprimiu-se a etapa de homogeneização das mesmas, ou seja, elas foram utilizadas de forma integral, conforme recolhidas do chão da serraria, sem passar por um moinho e peneira. Foram utilizadas duas resinas poliuretanas de baixo impacto ambiental, e uma resina de ureia-formaladeído, e os painéis foram produzidos em alta e média densidade, com maravalhas provenientes da madeira de Pinus Elliottii, Pinus Taeda, e também de Eucalyptus urograndis. Além dos ensaios exigidos por norma, foram realizados ensaios de colorimetria, rugosidade, condutividade térmica, porosimetria por intrusão de mercúrio e microscopia eletrônica de varredura. Os resultados comprovaram a viabilidade técnica dos painéis, e mostraram que com alguns ajustes é possível melhorar as propriedades dos mesmos para que eles fiquem de acordo com as exigências de sua aplicação final. / Wood processing generates huge amounts of solid residues throughout its commercial cycle from silviculture to sawn-wood production, and the destination given to such residues is influenced by: the existence of a local market capable of absorbing it; existence of a recycling culture; technology available to transform the material into other products or energy to be imputed back to the production process; and other factors. The main trend in Brazil follows two distinct lines, in which the residues are sometimes discarded in natura or even burned without any regards to energy that is being wasted, or the residues are used to energy production. Besides being a good alternative, incinerating the residues to produce energy may not be the best way to deal with them since the carbon stored in the wood is released back to the atmosphere, and this action doesn\'t conform to the national policy on solid residues which prioritizes recycling of the material. Raw wood shavings from Pinus taeda, Pinus elliottii and Eucalyptus urograndis were used to produce the particleboards, they were collected from the sawmill floor and used without any processing to regulate the particle dimension, they were only divided into Pinusand Eucalyptus; two polyurethane and one urea-formaldehyde resin were chosen to be part of the experiment. Besides the usual tests suggested by the standards, this research also evaluated the particleboards on surface roughness, spectrophotometry, heat conduction, percentage of pores and electronic microscopy. Technical viability of the particleboards was confirmed by the tests applied, with a few refinements to be considered in order to adequate the particleboard to the final application.

O Paricá (Schizolobium amazonicum) é uma espécie nativa do Brasil com ampla distribuição geográfica. Sua plantação e utilização estão em constante crescimento, devido às características apresentadas pela espécie. A principal utilização da madeira de Paricá tem sido a fabricação de lâminas de compensados. Entretanto, esses painéis experimentam redução de oferta, devido sua substituição por OSB. O presente trabalho teve como objetivo principal avaliar a viabilidade técnica de produção de painéis OSB fabricados com partículas de madeira da espécie Schizolobium amazonicum e resina poliuretana à base de óleo de mamona. Com a finalidade de proporcionar maior durabilidade e qualidade a estes painéis, também foi avaliada a influência do tratamento das partículas com preservante CCA e CCB e a variação de três teores de adesivo (8, 10 e 12%). O desempenho dos painéis para as propriedades de inchamento em espessura e absorção de água após períodos de 2 e 24 horas de imersão, módulo de elasticidade (MOE) e módulo de ruptura (MOR) para as direções paralela e perpendicular à orientação das partículas e adesão interna, foram avaliados segundo o documento normativo europeu EN 300 (2006). A resistência ao arrancamento de parafuso de face e de topo foi investigada de acordo com a norma brasileira ABNT NBR 14810-2 (2006). Os resultados apontaram excelentes propriedades físico-mecânicas para os painéis OSB produzidos neste estudo, quando comparados com os valores mínimos recomendados pelas normas citadas e com os valores encontrados na literatura, para painéis desta natureza com finalidades comerciais. Desta maneira ficou comprovada a viabilidade da utilização da espécie Paricá, quando tratada com preservantes CCA e CCB, e quando utilizada \"in natura\", juntamente com a resina poliuretana à base de óleo de mamona na fabricação de painéis OSB. / Paricá (Schizolobium amazonicum) is a Brazilian native wood specie, with wide geographic distribution. Their plantation and utilization are constantly growing due to the features presented by the specie. Primary use of wood has been in manufacture of plywood sheets. However, these panels present a gradual offer reduction, being replaced by OSB. This study aimed to assess the technical feasibility of producing OSB, using Paricá particles and castor oil based polyurethane resin. With the purpose of improve durability and quality of these panels, effect of treating the particles with preservative CCA and CCB and the variation of three levels of adhesive (8%, 10% and 12%) were also evaluated. OSB performance in thickness swelling and water absorption after periods of 2 to 24 hours of immersion, modulus of elasticity (MOE) and modulus of rupture (MOR), directions parallel and perpendicular to the particles orientation and internal bonding were evaluated according to the European normative document EN 300 (2006). Pullout strength of the screw (face and top) was investigated according to norm ABNT NBR 14810 (2006). The results showed excellent physical and mechanical properties for the OSB produced in this study, when compared with the minimum recommended by the standards and the values cited in the literature, such panels for commercial purposes. Thus it was proved the feasibility of using Paricá specie when treated with preservatives CCA and CCB, and when used \"in natura\" with castor-oil based polyurethane resin in OSB production.

O CCB (sais de cromo, cobre e boro) surgiu como alternativa ao CCA, apresentando menor toxicidade ao meio ambiente e em muitos casos conferindo excelentes propriedades mecânicas à madeira. Estima-se que, de 15 a 20% (aproximadamente 240 mil \'M POT.3\'/ano) da madeira tratada no Brasil atualmente sejam resíduos, considerando-se apenas aqueles provenientes do seu beneficiamento, desconsiderando os produtos pós-consumo. Por outro lado, o Brasil possui excelentes condições para a produção dos painéis aglomerados, com produção estimada atualmente em 2,5 milhões \'M POT.3\'/ano. Observando o crescimento do mercado de painéis à base de madeira e a constante busca por produtos sustentáveis, este trabalho teve como objetivo principal a análise da viabilidade de produção de chapas de partículas, empregando-se resíduos de Pinus sp tratado com preservante CCB e resina poliuretana à base de mamona. Foram variados parâmetros de produção para obtenção de melhores condições de processo, sendo estes: quantidade de partículas, com 1300g e 1400g; teor de adesivo, de 12% e 15% e; tempo de prensagem, de 10 e 12 minutos. Caracterizaram-se as partículas empregadas quanto as suas propriedades físicas e morfológicas, além da análise dos painéis quanto às características físico-mecânicas, segundo NBR 14810-3 (2006), submetendo-se também amostras com melhores desempenhos ao Envelhecimento Artificial Acelerado, conforme ASTM G155 (1999) e análise da morfologia, por meio de ensaios de Microscopia Eletrônica de Varredura (MEV) e Porosimetria por Intrusão de Mercúrio. Determinou-se também a retenção dos ingredientes ativos de preservante nas partículas e chapas, para avaliação de possíveis perdas na retenção devido ao processo de prensagem. Os resultados apontaram para excelentes propriedades físicas e mecânicas das chapas de partículas, em alguns casos em média 50% superiores ao estipulado pela norma brasileira em questão e superiores aos requisitos das normas internacionais. Assim, ficou evidenciada a viabilidade de produção dos painéis com os insumos estudados bem como seu potencial de emprego para as finalidades compatíveis com produtos desta natureza. / CCB (chromium, copper and boron sales) has risen as an alternative to CCA, because of its toxicity level and, in several cases, conferring high properties to treated wood. In Brazil, some evaluations show that nearly 15 to 20% (something like 240.000 \'M POT.3\'/year) of this wood are residues generated by processing phases, without taking in account pos-used product. Besides, Brazilian particleboard industry produces 2.500.000 \'M POT.3\'/year. Observing wood based panels demand improvement and sustainable products search, the aim of this work is to confirm feasibility of producing particleboards with CCB treated Pinus sp residues and polyurethane resin based on castor oil. Different production parameters were employed in order to optimize process conditions, like: particles (1300g and 1400g); adhesive percentage (12 and 15%); pressure time (10 and 12 minutes). Particles were characterized by their physical and morphological properties. Panels\' performance was determined based on their physical and mechanical properties, as prescript in Brazilian Code NBR 14810-3 (2006). Special specimens were used in order to evaluate influence of accelerated aging as proposed in ASTM G155 (1999). Morphological aspects were analyzed by Scanning Electron Microscopy (SEM) and Mercury Intrusion Porosimetry. Active ingredients retention was also determined to establish casual lost after producing process. Results show excellent physical and mechanical properties, some of them 50% higher than NBR14810-3 and international codes requirements. Feasibility of producing particleboards like those studied was demonstrated as well as potential of their employing in same uses of commercial boards.

Thesis (M.S.) -- Mississippi State University. Department of Forest Products. / Title from title screen. Includes bibliographical references.

Thesis (Ph.D.)--Mississippi State University. Department of Forest Products. / Title from title screen. Includes bibliographical references.

The wood products industry is important to Sweden's prosperity, and is currently facing several challenges by increased global competition. To avoid the gradual decline of the industry’s contribution to the country’s revenues and employment opportunities, the Swedish wood products industry needs to increase the proportion of the raw material that is refined. New and efficient manufacturing technologies are essential to support this development. The implementation of automation in manufacturing needs to be supported by conscious and well-defined strategies. However, currently, there is a lack of knowledge regarding automation decisions in this industry. Therefore, the purpose of this thesis is to increase knowledge regarding which aspects should be taken into account when automation decisions are considered in the wood products industry. Three research questions are addressed: (1) What is the current state of manufacturing operations in the wood products industry? (2) What are the potential opportunities for automation in the wood products industry? And (3) What challenges can arise from automation in the wood products industry? The results presented in this thesis are based on four research papers. The first paper provides an overview of the current state of manufacturing operations in the wood products industry. The second paper examined the impact of the raw material on manufacturing operations in the wood products industry. The third paper assessed how the levels of automation in manufacturing impact operational performance. The fourth paper examined automation opportunities and challenges to gain a better understanding of the reasoning behind automation decisions in the industry. In general, it is concluded that automation decisions in the wood products industry tend to be based on “gut feeling” and previous experience with automation rather than well-defined decisions and strategies. This is due to inadequate knowledge and familiarity with automation technologies in manufacturing. Furthermore, the findings showed that different aspects of manufacturing interact and impact each other. For this reason, it is essential to take into account other aspects of manufacturing when considering automation decisions. / ProWOOD

O CCB (sais de cromo, cobre e boro) surgiu como alternativa ao CCA, apresentando menor toxicidade ao meio ambiente e em muitos casos conferindo excelentes propriedades mecânicas à madeira. Estima-se que, de 15 a 20% (aproximadamente 240 mil \'M POT.3\'/ano) da madeira tratada no Brasil atualmente sejam resíduos, considerando-se apenas aqueles provenientes do seu beneficiamento, desconsiderando os produtos pós-consumo. Por outro lado, o Brasil possui excelentes condições para a produção dos painéis aglomerados, com produção estimada atualmente em 2,5 milhões \'M POT.3\'/ano. Observando o crescimento do mercado de painéis à base de madeira e a constante busca por produtos sustentáveis, este trabalho teve como objetivo principal a análise da viabilidade de produção de chapas de partículas, empregando-se resíduos de Pinus sp tratado com preservante CCB e resina poliuretana à base de mamona. Foram variados parâmetros de produção para obtenção de melhores condições de processo, sendo estes: quantidade de partículas, com 1300g e 1400g; teor de adesivo, de 12% e 15% e; tempo de prensagem, de 10 e 12 minutos. Caracterizaram-se as partículas empregadas quanto as suas propriedades físicas e morfológicas, além da análise dos painéis quanto às características físico-mecânicas, segundo NBR 14810-3 (2006), submetendo-se também amostras com melhores desempenhos ao Envelhecimento Artificial Acelerado, conforme ASTM G155 (1999) e análise da morfologia, por meio de ensaios de Microscopia Eletrônica de Varredura (MEV) e Porosimetria por Intrusão de Mercúrio. Determinou-se também a retenção dos ingredientes ativos de preservante nas partículas e chapas, para avaliação de possíveis perdas na retenção devido ao processo de prensagem. Os resultados apontaram para excelentes propriedades físicas e mecânicas das chapas de partículas, em alguns casos em média 50% superiores ao estipulado pela norma brasileira em questão e superiores aos requisitos das normas internacionais. Assim, ficou evidenciada a viabilidade de produção dos painéis com os insumos estudados bem como seu potencial de emprego para as finalidades compatíveis com produtos desta natureza. / CCB (chromium, copper and boron sales) has risen as an alternative to CCA, because of its toxicity level and, in several cases, conferring high properties to treated wood. In Brazil, some evaluations show that nearly 15 to 20% (something like 240.000 \'M POT.3\'/year) of this wood are residues generated by processing phases, without taking in account pos-used product. Besides, Brazilian particleboard industry produces 2.500.000 \'M POT.3\'/year. Observing wood based panels demand improvement and sustainable products search, the aim of this work is to confirm feasibility of producing particleboards with CCB treated Pinus sp residues and polyurethane resin based on castor oil. Different production parameters were employed in order to optimize process conditions, like: particles (1300g and 1400g); adhesive percentage (12 and 15%); pressure time (10 and 12 minutes). Particles were characterized by their physical and morphological properties. Panels\' performance was determined based on their physical and mechanical properties, as prescript in Brazilian Code NBR 14810-3 (2006). Special specimens were used in order to evaluate influence of accelerated aging as proposed in ASTM G155 (1999). Morphological aspects were analyzed by Scanning Electron Microscopy (SEM) and Mercury Intrusion Porosimetry. Active ingredients retention was also determined to establish casual lost after producing process. Results show excellent physical and mechanical properties, some of them 50% higher than NBR14810-3 and international codes requirements. Feasibility of producing particleboards like those studied was demonstrated as well as potential of their employing in same uses of commercial boards.