Thesis (MSc)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The extractive materials in wood often cause pitch problems in pulp mills. During pulping and bleaching extractives are released from the wood and pulp and later stick to ceramic and metal parts, forming pitch deposits. Pitch deposits impair both product quality and production rates. It decreases the efficiency of pulp washing, screening, centrifugal cleaning, and refining, and can disrupt many paper machine operations. The deposits also break loose from equipment and cause spots in the final product. There are a few triggering mechanisms that induce pitch deposition. Hydrodynamic or mechanical shear can destabilise the colloidal pitch emulsion, causing pitch to agglomerate and deposits to form. Similarly, sudden temperature drops and/or pH shocks and/or the introduction of water hardness ions from fresh water inlets or showers can also cause pitch deposits by destabilising the colloidal pitch emulsion. Inorganic salts, such as calcium carbonate, can catalyse pitch deposition by acting as the building blocks for the sticky pitch. Calcium ions in the white water can react with fatty acids, forming insoluble, sticky calcium soaps. Triglycerides have also been shown to be a major contributor to pitch deposition in kraft pulping and bleaching mills. It forms a sticky deposit to which less sticky particles attach. To attain an improved understanding of pitch problems associated with the kraft pulping and bleaching of Eucalyptus spp., various analyses were done on wood- and pulp extractives and pitch from a South African kraft pulp mill. High molecular weight compounds (involatile) constituted a large portion of the extracts and pitch. Approximately 40% of volatile Eucalyptus grandis extract was f3-sitosterol, with fatty acids (22.8%) and triglycerides (15.5%) also making a substantial contribution. Fatty acid amides were a prominent fraction of pulp extracts from the latter stages of bleaching. The amides constituted 38.3% and triglycerides 10.1% to total volatile pitch deposits. Lipases hydrolyse triglycerides and could therefore help to reduce pitch problems. Consequently 381 filamentous fungi isolated from indigenous and commercial forests in South Africa were screened for lipase activity on tributyrin and Tween 80. Eight strains were selected and the tributyrin and Tween 80 assays were repeated by monitoring lipase activity over a seven-day period. The selected strains were also assayed for their activity toward p-nitrophenyl palmitate. Ophiostoma piliferum Cartapip 58™ and Phanerochaete chrysosporium BKM-F-1767, two strains known for respectively their biodepitching and biopulping ability, were' used as controls. A few of the strains compared well and even outperformed the control strains, indicating their potential for use in pitch control. The effect of pretreatment with the eight selected fungal strains on E. grandis wood- and pulp extractives was determined. Cartapip 58™ and P. chrysosporium BKM-F-1767 were used as control strains. Several of the strains compared well to the control strains in their ability to reduce the triglyceride content of wood extract. The South African isolate, white-rot fungus Phanerochaete psuedomagnoliae nom. prov., reduced triglyceride content significantly. Consequently it can act as an agent for both biopulping and biodepitching. The treated wood samples had a lower triglyceride content than the sterile controls. Consequently more triglycerides would be released into process waters by the sterile controls than the treated samples. The effect of commerciallipases on deposited brown stock pulp extract was also evaluated. The lipases did not reduce the triglyceride content of the deposited extract. The addition of lipases in pulping and bleaching processes would therefore not affect already deposited pitch. / AFRIKAANSE OPSOMMING: Die ekstrakstowwe van hout veroorsaak dikwels 'n neerslag tydens verpulping. Gedurende verpulping en bleiking kom ekstrakstowwe van die hout enpulp vry en kleef aan keramiek- en metaalonderdele. Gevolglik benadeel dié neerslag produkkwaliteit en produksietempo. Dit verlaag die effektiwiteit van pulpwas, sifting, sentrifugale skoonmaakprosesse en suiwering, en kan die werkverrigting van papiermasjiene ontwrig. Die neerslag kan ook later los breek en kolletjies op die finale produk veroorsaak. Verskeie meganismes kan die neerslag veroorsaak. Hidrodinamiese of meganiese wrywing kan die kolloïdale ekstrakstofemulsie destabiliseer en sodoende die ekstrakstof laat konglomereer en neerslaan. Op soortgelyke wyse veroorsaak skielike temperatuurverlaging en/of pH-skokke en/of die toevoeging van ione in varswater om waterhardheid te beheer ook die neerslag deur die kolloïdale ekstrakstofemulsie te destabiliseer. Anorganiese sout soos kalsiumkarbonaat kan neerslagvorming kataliseer omdat dit optree as bousteen vir die klewerige, sementagtige ekstrakstowwe. Kalsiumione in die proseswater kan ook reageer met vetsure om onoplosbare, klewerige kalsiumsepe te vorm. Dit is bewys dat trigliseriede een van die hoofoorsake is in die vorming van die neerslag tydens kraft verpulpingen bleikingprosesse. Om die neerslagreaksie wat met die kraft verpulping en bleiking van Eucalyptus spp. geassosieer word, beter te verstaan, is verskeie analises op hout- en pulpekstrakte asook die neerslag van 'n Suid-Afrikaanse kraft verpulpingsaanleg uitgevoer. Hoë molekulêre massa (nie-vlugtige) stowwe het 'n groot gedeelte van die ekstrakte en neerslag uitgemaak. Ongeveer 40% van die vlugtige Eucalyptus grand is ekstrak bestaan uit ~-sitosterol met vet sure (22.8%) en trigliseriede (15.5%) wat ook aansienlike bydraes lewer. Vetsuuramiede verteenwoordig 'n beduidende komponent van pulpekstrak by die laaste stadiums van bleiking. Die amiede het 38.3% en trigliseriede 10.1%tot die vlugtige fraksie van die neerslag bygedra. Lipases hidroliseer trigliseriede en kan dus help om neerslagprobleme te voorkom. Gevolglik is 381 filamentagtige fungi geïsoleer uit inheemse en kommersiële woude van Suid-Afrika en hul lipase-aktiwiteit op tributyrin en Tween 80 geëvalueer. Agt rasse is geselekteer en die tributyrin en Tween 80 toetse is herhaal deur lipase-aktiwiteit oor 'n sewe-dag periode te monitor. Die geselekteerde rasse is ook getoets vir lipase-aktiwiteit met p-nitrofenielpalmitaat. Ophiostoma piliferum Cartapip 58™ en Phanerochaete chrysosporium BKM-F-1767, twee rasse wat daarvoor bekend staan vir onderskeidelik hul vermoë om houtekstrakstowwe te verminder en te bioverpulp, is as kontroles gebruik. 'n Paar van die geselekteerde rasse het goed vergelyk en selfs beter presteer as die kontrolerasse; 'n aanduiding van hul potensiaal om neerslagreaksies te beheer. Die effek van voorafbehandeling met die agt geselekteerde fungi rasse op E. grandis hout- en pulpekstrak is vasgestel. Cartapip 58™ en P. chrysosporium BKM-F-1767 is gebruik as kontrolerasse. Verskeie rasse het goed vergelyk met die kontrolerasse in hul vermoë om die trigliseriedinhoud van die houtekstrak te verlaag. Die Suid-Afrikaanse isolaat, witverrottingswam Phanerochaete pseudomagnoliae nom. prov., het ook die trigliseried inhoud beduidend verminder. Gevolglik sou dit as 'n middel kon dien vir beide neerslagvoorkoming en bioverpulping. Die trigliseriedinhoud van die behandelde monsters was laer as dié van steriele kontroles. Gevolglik sal meer trigliseriede in proseswater vrygestel word deur die steriele kontroles as die behandelde monsters. Die effek van kommersiële lipases op ongebleikte kraft pulpekstrakneerslag is ook geëvalueer. Omdat lipases nie die trigliseriedinhoud van die neerslag kon verlaag nie sal die gebruik van lipases dus nie die ekstrakstofneerslag in verpulpings- en bleikingsprosesse beïnvloed nie.

A aplicação de um piso de madeira maciça sobre um contrapiso de concreto dá origem a um sistema que une dois materiais com diferentes características higroscópicas, e no qual a movimentação da umidade é ainda um fenômeno pouco conhecido. Visando um melhor entendimento desse fenômeno, a presente pesquisa buscou avaliar diferentes equipamentos para medir o teor de umidade do concreto, desenvolver uma metodologia para quantificar a água evaporável presente no substrato mineral e, a partir desses resultados, sugerir o teor de umidade do substrato mais adequado à aplicação de um revestimento de madeira. Corpos de prova de concreto, preparados com traço 3:1:1 e relação água cimento em torno de 0,5, foram submetidos a secagem ao ar, sendo que a variação do teor de umidade do concreto ao longo do tempo foi acompanhada pela perda de massa e com a utilização de medidores elétricos de umidade do tipo resistência e de contato.. Com o auxílio da análise de regressão foi possível estabelecer equações de correção para as leituras de umidade dos aparelhos. Para a quantificação da água evaporável no concreto, foi desenvolvido um corpo de prova utilizando-se cilindros de MDF com 6,0 cm de comprimento e 4,8 cm de diâmetro, inseridos em tubo de PVC e com uma das extremidades vedada com filme plástico e silicone. O cilindro de MDF mostrou-se um indicador eficiente da presença de água evaporável no concreto, uma vez que as taxas de adsorção pelo MDF puderam ser diretamente correlacionadas às taxas de evaporação pelo concreto. O efeito do adesivo no sistema concreto-madeira foi avaliado através da variação do gradiente de umidade em madeira de Jatobá (Hymenaea sp). Tacos de Jatobá, com dimensões de 100 mm x 80 mm x 18 mm e nos quais foram colocados sensores a 4 mm e a 17 mm de profundidade, foram colados em corpos de prova de concreto utilizando-se adesivo a base de PVA com 60% de sólidos. Os resultados mostraram que a água contida no adesivo não foi totalmente adsorvida pelo taco e o gradiente de umidade no sentido da espessura apresentou relação com o teor de umidade à profundidade de 17 mm, confirmando a hipótese de que existe um fluxo de umidade na interface concreto-madeira. / The application of solid wood flooring over a concrete subfloor originates a system joining two materials with different hygroscopic characteristics, and in which the moisture movement still is a little known phenomena. Looking for the better understanding of moisture relationship in this system, the present research evaluated different equipments to measure concrete moisture content, to develop a methodology to quantify the vaporizable water present in the mineral substrate and, according to these results, to suggest the substrate moisture content more adequate to application of a wooden covering. Sample test of concrete, prepared with trace 3:1:1 and relation water/cement around 0.5, were submitted to air drying and the variation of the concrete moisture content during the process was registered by the mass loss and with the use of electric moisture meters of resistance and contact types. Through regression analysis it was possible to establish equations to correct moisture meters readings. To quantify the vaporizable water present in concrete, a sample test was developed using cylinders of MDF with 6.0 cm of length and 4.8 cm of diameter, inserted in a PVC tube and with one of the extremities closed with plastic film and silicone. The MDF cylinder was an efficient indicator to quantify vaporizable water in the concrete, considering that the moisture adsorption rate of MDF samples could be directly correlated to the concrete evaporation rate. The effect of adhesive in concrete-wood system was evaluated through the variation of moisture content gradient in Jatobá lumber (Hymenaea sp). Flooring samples of Jatobá, with dimensions of 100 mm x 80 mm x 18 mm and moisture sensors inserted at depths of 4 mm and 17 mm, were glued to concrete sample test using a PVA based adhesive with 60% of solids. Results showed that the water contained in the adhesive was not totally adsorbed by the flooring sample and the moisture gradient across sample thickness is correlated to moisture content at depth of 17 mm, what confirm the moisture flow between concrete and wood.

A madeira quando usada em contato direto com o solo, é atacada por agentes biológicos, principalmente fungos apodrecedores e cupins subterrâneos. Uma maneira de ampliar as possibilidades de utilização das espécies de baixa durabilidade natural, como as do gênero Pinus, é através do tratamento químico preservante. No entanto, faltam informações disponíveis que indiquem a durabilidade destas madeiras em serviço. A fim de se determinar a durabilidade da madeira do gênero Pinus tratada com preservantes, a Escola Superior de Agricultura "Luiz de Queiroz" e o Instituto Florestal do Estado de São Paulo instalaram, em 1980, campos de apodrecimento segundo método de ensaio sugerido pelo IUFRO (International Union of Forestry Research Organizations). As espécies utilizadas no ensaio foram o Pinus elliottii Engl. var. elliottii, o Pinus caribaea Mor. var. hondurensis, B & G., o Pinus oocarpa Shied e o Pinus kesiya Royle ex Gordon; tratadas com os preservantes CCA tipos A, B e C, CCB e pentaclorofenol, em cinco níveis de retenção. Em continuidade ao projeto, foi inspecionado o campo instalado na Estação Experimental de Mogi-Guaçu, visando avaliar o estado de sanidade do material. A análise dos resultados obtidos até o momento, 21 anos de exposição demonstrou que não houve diferença no comportamento entre espécies. Os índices de comportamento mais altos (maior expectativa de durabilidade) correspondem aos tratamentos com CCA tipos A, B e C em retenções acima de 7,5 kg/m3. Mesmo para os tratamentos que apresentaram os menores índices de comportamento (CCA tipo C com retenções de 5,0 kg/m 3 e CCB com 5,9 kg/m 3 ), é prevista uma durabilidade de 30 anos em serviço. / When used in ground contact, wood is deteriorated by biological agents, as root fungi and subterranean termites. A way to increase the use of wood species of low natural durability, as the Pinus lumber, is the preservative treatment. However, there is a lack of information indicating the durability of treated wood. In order to determine the durability of preservative treated Pinus lumber, the Escola Superior de Agricultura "Luiz de Queiroz" and the Instituto Florestal do Estado de São Paulo installed, in 1980, fields tests according to the IUFRO (International Union of Forestry Research Organizations). The species under test were Pinus elliottii Engl. var. elliottii, Pinus caribaea Mor. var. hondurensis, B & G., Pinus oocarpa Shied and Pinus kesiya Royle ex Gordon; treated with the preservatives CCA types A, B and C, CCB and pentachlorophenol, in five retention levels. In continuity to the project, the material installed in the test site of Experimental Station of Mogi-Guaçu was inspected, to evaluate the degree of attack. The analysis of results obtained till now, after 21 years of exposure, demonstrated that there are no differences in durability related with species. The highest performance index (longer durability expectation) correspond to treatments with CCA types A, B and C in retentions above 7,5 kg/m3. Even for the treatments that presented lowest performance index (CCA type C with retention of 5,0 kg/m 3 and CCB with 5,9 kg/m 3 ), the durability expectation is 30 years in service.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18107号 / 理博第3985号 / 新制||理||1575(附属図書館) / 30965 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 朝倉 彰, 講師 宮崎 勝己, 教授 疋田 努 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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Reclaimed wood is material salvaged from old, abandoned buildings that offers sustainable living to communities. There have been previous studies on reclaimed wood, but a limited amount linking reclaimed wood to consumerism. In August 2021, an online survey was conducted to gauge consumers’ knowledge of the industry and attitudes on reclaimed wood practices. Consumers are U.S. citizens 18 years of age or older. Study results indicate that respondents have little knowledge regarding reclaimed wood. Of the 1,516 respondents, 44% seem knowledgeable of reclaimed wood. Most respondents are not aware that reclaimed wood is a separate industry. Respondents believe there should be better marketing practices. Respondents also believe reclaimed wood to be environmentally friendly, durable, and aesthetically pleasing. The reasons respondents would purchase reclaimed wood are sustainability, aesthetics, and to exercise a need. Respondents acknowledge the importance of the origin of wood products. Respondents also acknowledge the importance of the industry.

The purpose of the thesis work is to increase knowledge about older wood materials. The quality of the material and how to take care of it, restore it and reuse it, will be investigated. The aim of the report is to help reduce the amount of wood waste that the construction sector is responsible for and indicate the differences that exist between wood today and wood from the past. Due to the broad subject, there is a focus on wooden windows, which are used as examples in the report. The focus is carpentry wood andolder wood material before the middle of the 20th century. To achieve the goal, several interviews were conducted with experts in the field as well asa case study where older windows were replaced and what the consequences of that led to. The results show that wood production and the quality of timber have changed greatly. Before the year 1950, many natural forests that existed with slow-growing trees were used and much greater emphasis was placed on the quality of the material. Today's woodproduction is dominated by fast-growing trees and the trees are treated like a "bulk product". The trees are cut down all at once and sorted by area of use, rather than its individual characteristics. With the help of technological advances, the pursuit of efficiency in production has contributed to greater financial gain. Older wood materials turned out to have a higher quality compared to today's fast-growing timber. Properties of the older wood are higher density, denser annual rings, more resistant to moisture and above all a larger amount of heartwood. On the other hand, today's fast-growing woodmaterials are faster and easier to process. To carry out a restoration work of a window, competent craftsmen are required, of whichthere is currently a shortage. The demand for recycled wooden windows and interior doors has recently increased. Caring for older wooden windows is done by regular painting, scraping, and caulking of windows. The window replacement that wasinvestigated resulted in high costs and more emissions of carbon dioxide during the manufacture of the new windows, but energy consumption in the villa was reduced as the thermal insulation was improved.

This essay will address if and how it is possible to reuse and recycle wood waste and CDWW (construction and demolition wood waste). The background will have a short introduction and then be divided into 3 sections. The first section addresses similarities and differences between linear vs. circular economy. The second section will take up bioeconomy and how it is managed in the different countries in the world, and the last part takes up wood waste management. The purpose of this thesis is to investigate from literature if it is possible to reuse and recycle wood waste and CDWW. By reviewing case studies, see if it is possible to implement a practical sustainable recycling worldwide. There are four questions that will be answered to see if it is possible. Those are: 1, Are there enough volumes of wood waste for it to be worth to reusing/recycling it? 2, What opportunities does it provide and how can it affect society, economy, and the environment? 3, Is it worth investing in facilities that only accept wood waste and reuse/recycle the material? 4, How have the trends with wood waste been according to the data collected? The methods that have been used are literature study, qualitative and quantitative methods. Qualitative as an interview has been conducted, and quantitative as data for wood waste in Borås has been compiled. The result showed that there exist enough volumes for it to be worth reusing and recycling, however, the volumes has gone down significantly and are not stable, though this could be argued due to the COVID-19 pandemic and will most likely change and go up in volume within the next few years. There have not been any studies on how the society could be affected by reusing and recycle wood waste, although from an economic and environmental perspective it shows a positive outcome, such as new jobs get created and less deforestation and less reduction of biological diversity. Depending on the type of wood waste the facility receives, it can affect whether it is profitable or not, as the more hazardous chemicals exist in the wood residues, the more difficult and expensive the treatments and recycling becomes.

Lack of dimensional stability and susceptibility to the action of xylophagous organisms make wood a challenging material to work with. E-Caprolactam is a water-soluble cyclic amide chemical with low mammalian toxicity, that can be used as a bulking agent to improve the dimensional stability of wood and offers protection against subterranean termites and several wood degradant fungi. E-Caprolactam delivers a similar level of dimensional stability as that provided by PEG-1000, a chemical extensively studied in the past decades and a standard dimensional stabilizer agent for wood. Regarding wood protection, E-Caprolactam exhibits efficacy against wood decay fungi and termites at very low levels compared to PEG-1000. If water leaching can be inhibited for this product, e-Caprolactam can be considered as a strong candidate for the wood decking industry. In addition to the evaluation of E-Caprolactam for wood dimensional stabilization and preservation this dissertation covers the development of an apparatus developed to automate wood sorption and desorption studies, and their influence in the wood dimensional behavior. Product design techniques and prototyping studies were conducted, and calibration procedures were made. This apparatus is still in development, but it shows potential for increasing the accuracy of shrinking and swelling measurements and efficiency for dimensional stabilization studies.

This research focuses on the evaluation of many aspects of the American Wood Protection Association (AWPA) Standard E1-97, “Standard Method for Laboratory Evaluation to Determine Resistance to Subterranean Termites.” This standard is used extensively for testing the efficacy of new products and preservative systems against subterranean termite species. Research was done to determine what changes, if any, are needed for testing against subterranean termite species such as Coptotermes formosanus (Shiraki) and species of native termite genus Reticulitermes (Holmgren), primarily R. flavipes (Kollar). Variables from the current standard were tested to determine effects of parameters such as moisture of sand substrate; size, type, and location of test material within a test bottle; and termite number and ratios of workers to soldiers per test bottle. Research also improved comprehension of termite biology in a laboratory setting, enabling researchers to develop new and safer control methods.