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Sample records for eucalyptus kraft pulps

  1. Eucalyptus kraft pulp production: Thermogravimetry monitoring

    International Nuclear Information System (INIS)

    Barneto, Agustin G.; Vila, Carlos; Ariza, Jose

    2011-01-01

    Highlights: → Thermogravimetric analysis can be used to monitor the pulping process in a pulp mill. → ECF bleaching process affects the crystalline cellulose volatilization. → The fibre size has an influence on composition and thermal behavior of pulp. - Abstract: Under oxidative environment the thermal degradation of lignocellulosic materials like wood or pulp is sensitive to slight composition changes. For this, in order to complement the chemical and X-ray diffraction results, thermogravimetric analyses (TGA) were used to monitor pulp production in a modern pulp mill. Runs were carried out on crude, oxygen delignified and bleached pulps from three eucalyptus woods from different species and geographical origins. Moreover, with the modeling of thermogravimetric data, it was possible to obtain an approximate composition of samples which includes crystalline and amorphous cellulose. TGA results show that pulping has an intensive effect on bulk lignin and hemicellulose, but it has limited influence on the removal of these substances when they are linked to cellulose microfibril. The stages of oxygen delignification and bleaching, based in chlorine dioxide and hydrogen peroxide, increase the crystalline cellulose volatilization rate. These changes are compatible with a more crystalline microfibril. The influence of the fibre size on pulp composition, crystallinity and thermal degradation behavior was observed.

  2. Evaluation of bleachability on pine and eucalyptus kraft pulps

    Directory of Open Access Journals (Sweden)

    Marcela Freitas Andrade

    2013-09-01

    Full Text Available In recent decades, the pulp industry has been changing and improving its manufacturing processes in order to enhance production capacity, product quality and environmental performance. The aim of this study was to evaluate the bleachability effect on the efficient washing and alkaline leaching in eucalyptus and pine Kraft pulps using three different bleaching sequences: AD(EPD, A/D(EPDP and DHT(EPDP. This study was carried out in two stages. In the first part, the optimum conditions for pulp bleaching in order to achieve a brightness of 90% ISO were established. The second step was a comparative study between the pulps that received alkaline leaching and efficient washing with reference pulp (without treatment. The brightness, viscosity, kappa number and HexA in pulp were analyzed. The three sequences studied reached the desired brightness, but the sequence AD(EPD produced a lower reagent consumption for the same brightness. In the three sequences studied, the efficient washing of the pulp after oxygen delignification has contributed significantly to the removal of dissolved organic and inorganic materials in the pulp and the alkaline leaching decreased significantly the pulp kappa number due to a higher pulp delignification and bleachability.

  3. Study on the Modification of Bleached Eucalyptus Kraft Pulp Using Birch Xylan

    Science.gov (United States)

    Wenjia Han; Chuanshan Zhao; Thomas Elder; Rendang Yang; Dongho Kim; Yunqiao Pu; Jeffery Hsieh; Arthur J. Ragauskas

    2012-01-01

    In this study, birch xylan was deposited onto elementally chlorine free (ECF) bleached eucalyptus kraft pulp, and the corresponding changes in physical properties were determined. An aqueous 5% birch xylan solution at pH 9 was added to 5 wt% slurry of bleached kraft eucalyptus fibers, with stirring at 70 C for 15 min after which the pH was adjusted to 5–6. The xylan...

  4. Effect of shortening kraft pulping integrated with extended oxygen delignification on biorefinery process performance of eucalyptus.

    Science.gov (United States)

    Li, Jing; Zhang, Chunyun; Hu, Huichao; Chai, Xin-Sheng

    2016-02-01

    The aim of this work was to study the impact of shortening kraft pulping (KP) process integrated with extended oxygen delignification (OD) on the biorefinery process performance of eucalyptus. Data showed that using kraft pulps with high kappa number could improve the delignification efficiency of OD, reduce hexenuronic acid formation in kraft pulps. Pulp viscosity for a target kappa number of ∼10 was comparable to that obtained from conventional KP and OD process. The energy and alkali consumption in the integrated biorefinery process could be optimized when using a KP pulp with kappa number of ∼27. The process could minimize the overall methanol formation, but greater amounts of carbonate and oxalate were formed. The information from this study will be helpful to the future implementation of short-time KP integrated with extended OD process in actual pulp mill applications for biorefinery, aiming at further improvement in the biorefinery effectiveness of hardwood. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Process parameters affecting the delignification of eucalyptus kraft pulp with peroxyacetic acid

    OpenAIRE

    Chandranupap, P.; Chaivichit, P.; Chandranupap, P.

    2004-01-01

    Various process parameters affecting eucalyptus kraft pulp delignification with peroxyacetic acid were investigated. The results showed that pH was an important factor. The delignification rate increased with increasing pH to the value of 6. High delignification rate was obtained when the pulp was chelated with Na4-EDTA prior to the peroxyacetic acid stage. Therefore, delignification reaction rate depends on peroxyacid charge, temperature, pH and metal content of pulp.

  6. Ozone bleaching of South African Eucalyptus grandis kraft pulps containing high levels of hexenuronic acids

    CSIR Research Space (South Africa)

    Andrew, JE

    2013-08-01

    Full Text Available was a preliminary investigation into the use of ozone in bleaching sequences for kraft pulps produced from South African Eucalyptus grandis wood chips, which typically contained high amounts of hexenuronic acids (HexA). The objective of the study...

  7. Solution blow spun nanocomposites of poly(lactic acid)/cellulose nanocrystals from Eucalyptus kraft pulp

    Science.gov (United States)

    Cellulose nanocrystals (CNCs) were extracted from Eucalyptus kraft pulp by sulfuric acid hydrolysis, and esterified with maleic anhydride (CNCMA). The incorporation of sulfate ester groups on the cellulose surface resulted in higher stability of the nanoparticles in aqueous suspensions and lower the...

  8. Grouping eucalyptus species in kraft pulp process for cost reduction

    Directory of Open Access Journals (Sweden)

    Apiwan Pichayadecha

    2014-12-01

    Full Text Available The objective of this research is to study the level of the important factors that can decrease total cost of pulp production. First of all, experts and experienced users identify the factors that affect the total production cost by applying the principle of 4M 1E cause and effect diagram. Then the primary factors were chosen based on 80% of their significance and tested by hypothesis for two population means. It was found that at the 95% confidence level the significant factors that have effects on the total production cost are amount of Effective alkali in white liquor and Kappa number. However, the proportion of easy delignification according to Eucalyptus species is considered as a significant factor based on various studies. Box-Behnken experiment is designed with respect to 3 mentioned factors and 3 levels of each factor. The response surface method (RSM is employed to determine the non-linear relation between the total cost as the response and the proportion of easy delignification, amount of Effective alkali in white liquor and Kappa number. To minimize the total cost, the optimal values of each factor are 75% of easy delignification, 112 grams per liter of Effective alkali in white liquor and 13.5 of kappa number. Under this optimal condition, the average total cost per ton of Eucalyptus is 13,393.91 Baht which is significantly less than the total cost of 15,517.06 Baht per ton before improvement.

  9. The impact of kappa number composition on eucalyptus kraft pulp bleachability

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    M. M. Costa

    2007-03-01

    Full Text Available Consumption of chemicals during ECF bleaching of kraft pulp correlates reasonably well with kappa number, which measures with KMnO4 the total amount of oxidizable material in the pulp. However, the method does not distinguish between the oxidizable material in residual lignin and other structures susceptible to oxidation, such as hexenuronic acids (HexAs, extractives and carbonyl groups in the pulp. In this study an attempt is made to separate the main contributors to the kappa number in oxygen - delignified eucalyptus Kraft pulps and evaluate how these fractions behave during ECF bleaching using chlorine dioxide as the sole oxidant (DEDD sequence. Residual lignin and HexAs proved to be the main fractions contributing to the kappa number and chlorine dioxide consumption in ECF bleaching. Pulp bleachability with chlorine dioxide increases with increasing HexAs content of the pulp but chlorine dioxide per se does not react with HexAs. Reduction of pulp with sodium borohydride under conditions for removing carbonyl groups has no impact on bleachability. No correlation was found between the pulp of the extractive content and pulp bleachability. The removal of HexAs prior to ECF bleaching significantly decreases the formation of chlorinated organics in the pulp (OX and filtrates (AOX as well as of oxalic acids in the filtrates.

  10. Inter-laboratory comparisons of hexenuronic acid measurements in kraft eucalyptus pulps using a UV-Vis spectroscopic method

    Science.gov (United States)

    J.Y. Zhu; H.F Zhou; Chai X.S.; Donna Johannes; Richard Pope; Cristina Valls; M. Blanca Roncero

    2014-01-01

    An inter-laboratory comparison of a UV-Vis spectroscopic method (TAPPI T 282 om-13 “Hexeneuronic acid content of chemical pulp”) for hexeneuronic acid measurements was conducted using three eucalyptus kraft pulps. The pulp samples were produced in a laboratory at kappa numbers of approximately 14, 20, and 35. The hexeneuronic acid contents of the three pulps were...

  11. Use of xylanase in the TCF bleaching of eucalyptus kraft pulp

    Energy Technology Data Exchange (ETDEWEB)

    Roncero, B.; Vidal, T.; Torres, A.L.; Colom, J.F. [Universitat Politecnia de Catalunya, Terrassa (Spain)

    1996-10-01

    Environmental pressures are forcing the pulp and paper industry to develop new technologies that reduce or eliminate the presence of various contaminants in bleaching plant effluents. Oxygen delignification techniques, replacement of elemental chlorine with chlorine dioxide, ozone, hydrogen peroxide and new agents as well as the use of xylanase enzymes for biobleaching, reduce o eliminate the production of chlorinated organic substances. This paper compares the sequence XOZP with OZP in the bleaching of Eucalyptus globulus kraft pulps. It has been studied the influence of enzymatic treatment on the consumption of bleaching agents: ozone and hydrogen peroxide. Chemical, physical, optical and refining properties of pulps, as well as COD and colour of effluent are also studied. The xylanase treatment is positive and it is possible to manufacture fully bleached pulps at high brightness and viscosity without using chlorine compounds at a low ozone and hydrogen peroxide consumption.

  12. Bleaching of kraft pulps produced from green liquor pre-hydrolyzed South African Eucalyptus grandis wood chips

    CSIR Research Space (South Africa)

    Andrew, JE

    2014-01-01

    Full Text Available The effect of hemicellulose pre-extraction of South African Eucalyptus grandis wood chips using green liquor, on subsequent kraft pulping and bleaching processes was studied. This was done in the context of a biorefinery mill producing both ethanol...

  13. Laccase-HBT bleaching of eucalyptus kraft pulp: influence of the operating conditions.

    Science.gov (United States)

    Moldes, D; Vidal, T

    2008-12-01

    Different operating conditions (viz. pulp consistency, oxygen pressure and treatment time) in the biobleaching of eucalyptus kraft pulp with the laccase-HBT system was tested in order to describe their effect and normalize a biobleaching protocol. A high O(2) pressure (0.6MPa) was found to result in improved laccase-assisted delignification of the pulp. Also, a high pulp consistency (10%) and a short treatment time (2h) proved the best choices with a view to obtaining good pulp properties (kappa number and ISO brightness) under essentially mild conditions. The laccase-HBT treatment was found to result in slight delignification (in the form of a 20-27% decrease in kappa number); however, an alkaline extraction stage raised delignification to 41-45%, a much higher level than those obtained in the control tests (16-23%). Also, the use of hydrogen peroxide in the extraction stage resulted in improved brightness (14-19%), but in scarcely improved delignification (4-7%). Treating the pulp with the laccase-HBT system reduced the amount of hydrogen peroxide required for subsequent alkaline bleaching by a factor of 3-4 relative to control tests.

  14. EVALUATION OF EUCALYPTUS KRAFT PULP LIGNIN THROUGH THE NITROBENZENE OXIDATION, COPPER OXIDE REDUCTION AND ACIDOLYSIS TECHNIQUES

    Directory of Open Access Journals (Sweden)

    Gustavo Ventorim

    2014-03-01

    Full Text Available http://dx.doi.org/10.5902/1980509813337This study aimed to evaluate the sensitiveness of the information obtained for the residual lignin from Eucalyptus grandis kraft pulps analyzed through the nitrobenzene oxidation, copper oxide (CuO reduction and acidolysis techniques. The chips were cooked, resulting pulps of kappa number 14,5 and 16,9, respectively. Both lignins’ pulps were evaluated through three methods (nitrobenzene oxidation, copper oxide oxidation and acidolysis. Then, they were subjected to an oxygen delignification stage. The 16,9 kappa number pulp resulted in higher levels of non-condensed lignin structures by the acidolysis method, higher syringyl/vanillin ratios (S/V by the nitrobenzene and copper oxide methods and better performance in the oxygen delignification stage. The different methods allowed to differ the residual lignin pulps with kappa number 14,5 and 16,9, and the nitrobenzene oxidation method showed the highest sensitiveness in this study results.

  15. Solution blow spun nanocomposites of poly(lactic acid)/cellulose nanocrystals from Eucalyptus kraft pulp.

    Science.gov (United States)

    Parize, Delne Domingos da Silva; Oliveira, Juliano Elvis de; Williams, Tina; Wood, Delilah; Avena-Bustillos, Roberto de Jesús; Klamczynski, Artur Piotr; Glenn, Gregory Melvin; Marconcini, José Manoel; Mattoso, Luiz Henrique Capparelli

    2017-10-15

    Cellulose nanocrystals (CNCs) were extracted from Eucalyptus kraft pulp by sulfuric acid hydrolysis, and esterified with maleic anhydride (CNC MA ). The incorporation of sulfate ester groups on the cellulose surface resulted in higher stability of the nanoparticles in aqueous suspensions and lower thermal stability. Then, PLA/CNC and PLA/CNC MA nanocomposites were successfully obtained by solution blow spinning (SBS) using dimethyl carbonate (DMC) as solvent. CNC and CNC MA indicated to be acting both as nucleating agents or growth inhibitors of PLA crystal and tends to favor the formation of PLA crystals of higher stability. A fraction of the nanocrystals indicate to be exposed on the surface of the PLA fibers, since the hydrophilicity of the composite films increased significantly. Such composites may have potential application as filtering membranes or adsorbents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Comparative study of the efficiency of synthetic and natural mediators in laccase-assisted bleaching of eucalyptus kraft pulp.

    Science.gov (United States)

    Moldes, D; Díaz, M; Tzanov, T; Vidal, T

    2008-11-01

    The natural phenolic compounds syringaldehyde and vanillin were compared to the synthetic mediators 1-hydroxybenzotriazole, violuric acid and promazine in terms of boosting efficiency in a laccase-assisted biobleaching of eucalyptus kraft pulp. Violuric acid and 1-hydroxybenzotriazole revealed to be the most effective mediators of the bioprocess. Nevertheless, laccase-syringaldehyde system also improved the final pulp properties (28% delignification and 63.5% ISO brightness) compared to the process without mediator (23% and 61.5% respectively), in addition to insignificant denaturation effect over laccase. The efficiency of the biobleaching process was further related to changes in non-conventionally used optical and chromatic parameters of pulp, such as (L*), chroma (C*) and dye removal index (DRI) showing good correlation. Adverse coupling reactions of the natural phenolic mediators on pulp lignin were predicted by electrochemical studies, demonstrating the complexity of the laccase-mediator reaction on pulp.

  17. Chemical characteristics and Kraft pulping of tension wood from Eucalyptus globulus labill Características químicas e polpação Kraft de madeira de tração de Eucalyptus globulus labill

    Directory of Open Access Journals (Sweden)

    María Graciela Aguayo

    2012-12-01

    Full Text Available Tension (TW and opposite wood (OW of Eucalyptus globulus trees were analyzed for its chemical characteristics and Kraft pulp production. Lignin content was 16% lower and contained 32% more syringyl units in TW than in OW. The increase in syringyl units favoured the formation of β-O-4 bonds that was also higher in TW than in OW (84% vs. 64%, respectively. The effect of these wood features was evaluated in the production of Kraft pulps from both types of wood. At kappa number 16, Kraft pulps obtained from TW demanded less active alkali in delignification and presented slightly higher or similar pulp yield than pulps made with OW. Fiber length, coarseness and intrinsic viscosity were also higher in tension than in opposite pulps. When pulps where refined to 30°SR, TW pulps needed 18% more revolutions in the PFI mill to achieve the same beating degree than OW pulps. Strength properties (tensile, tear and burst indexes were slightly higher or similar in tension as compared with opposite wood pulps. After an OD0(EOD1 bleaching sequence, both pulps achieved up to 89% ISO brightness. Bleached pulps from TW presented higher viscosity and low amount of hexenuronic acids than pulps from OW. Results showed that TW presented high xylans and low lignin content that caused a decrease in alkali consumption, increase pulp strength properties and similar bleaching performance as compared with pulps from OW.Madeira de tração e oposta de árvores de Eucalyptus globulus foram analisadas quanto a suas características químicas e produção de polpa Kraft. A caracterização química da madeira de tração (TW de Eucalyptus globulus Labill. mostrou um conteúdo similar de celulose, alto conteúdo de xilanas e baixo conteúdo de lignina quando comparada com a madeira oposta (OW de uma mesma árvore. O conteúdo de lignina foi 16% menor e contém 32% mais unidades siringila em TW que em OW. O aumento das unidades siringila favoreceu a formação de ligações

  18. Xylan-hydrolyzing enzyme system from Bacillus pumilus CBMAI 0008 and its effects on Eucalyptus grandis kraft pulp for pulp bleaching improvement.

    Science.gov (United States)

    Duarte, Marta C Teixeira; da Silva, Elizete Cristina; de Bulhões Gomes, Isabel Menezes; Ponezi, Alexandre Nunes; Portugal, Edilberto Princi; Vicente, João Roberto; Davanzo, Ednilson

    2003-05-01

    The extracellular productions of beta-xylanase, beta-xylosidase, beta-glucosidase, beta-mannanase, arabinosidase, alpha-glucuronidase, alpha-galactosidase and Fpase from Bacillus pumilus CBMAI 0008 were investigated with three different xylan sources as substrate. The enzymatic profiles on birchwood, Eucalyptus grandis and oat were studied at alkaline and acidic pH conditions. B. pumilus CBMAI 0008 grown on the three carbon sources produced mainly beta-xylanase. At pH 10, the levels of xylanase were 328, 160 and 136 U/ml, for birch, oat and E. grandis, respectively. beta-Mannanase production was induced on E. grandis (5 U/ml) and arabinofuranosidase on oat (5 U/ml). Although small quantities of alpha-glucuronidase had been produced at pH 10, activity at pH 4.8 was 1.5 U/ml, higher than observed for Aspergillus sp. in literature reports. Preliminary assays carried out on E. grandis kraft pulp from an industrial paper mill (RIPASA S.A. Celulose e Papel, Limeira, SP, Brazil) showed a reduction of 0.3% of chlorine use in the pulp treated with the enzymes, resulting in increased brightness, compared to conventional bleaching. The enzymes were more efficient if applied before the initial bleaching sequence, in a non-pre-oxygenated pulp.

  19. Investigation of ESEM/EDX to measure liquor penetration and diffusion in Eucalyptus grandis wood chips during kraft pulping

    CSIR Research Space (South Africa)

    Grzeskowiak, V

    2011-01-01

    Full Text Available 2011. 6. Quinde A. (1994). Pulping additives in kraft pulping: Past, present and future. Spring Conference Canadian Pulp and Paper Ass. Jasper, Alberta. May 19 ? 21. 7. Stamm A.J. (1953). Diffusion and penetration mechanism of liquids into wood... and aspen wood chips using SEM/EDXA. J. Pulp and Paper Sci. 22(3): 71-77. 10. Jensen W., Folgelberg B.C. and Johanson M. (1960). Studies on the possibilities of using radioactive tracers to follow the penetration of cooking liquors into wood. Paperi ja...

  20. Future trends in environmental impact of eucalyptus-based Kraft pulp industry in Thailand: a scenario analysis

    NARCIS (Netherlands)

    Jawjit, W.; Kroeze, C.; Soontaranun, W.; Hordijk, L.

    2008-01-01

    This study explores possible future trends in the environmental impact of the Kraft pulp industry in Thailand between 2000 and 2020. Scenarios were developed to analyze the effect of different options to reduce the future environmental impact, and the costs associated with the implementation of

  1. MINERAL ELEMENTS IN WOODS OF EUCALYPTUS AND BLACK WATTLE AND ITS INFLUENCE IN A BLEACHED KRAFT PULP MILL

    Directory of Open Access Journals (Sweden)

    André Fredo

    2009-09-01

    Full Text Available Effluents are one of the most important problems in a pulp mill regarding to environmental subjects. With the purpose to reduce them, the mills are closing the internal cycles and reducing the water consumption. The wood, as the most significant source of non-process elements to the system, is responsible for some troubles to the industrial process. With the aim of evaluating their intake and to offer some informations for closing the loop, the contents of Al, Ca, Cu, Fe, K, Mg, Mn, Na, Ni, and Si were analysed in Acacia mearnsii, Eucalyptus dunnii, Eucalyptus globulus globulus, Eucalyptus grandis and Eucalyptus saligna woods. Wood samples were prepared by oven burning and acidic digestion methods, following analysis by ICP (inductively coupled plasm. Using also the results from silvicultural evaluation of trees and stands, they were calculated which elements were carried out from the site in larger amounts (K, Ca, Na, Al, Mn and Si and the species which exported largest amount of these elements (Eucalyptus dunnii and Eucalyptus globulus. The species with lower growth were Eucalyptus globulus and Eucalyptus dunnii, that leads to a bigger elements input and more potential industrial troubles. It was observed a range of 3.8 (Eucalyptus grandis up to 6 (Eucalyptus dunnii kg of analised mineral elements introduced to the process per ton of umbleached pulp produced. The Acacia mearnsii showed the lower level for Fe, Mn and Ni, being useful for oxygen, ozone and peroxide bleaching. The silicon observed in woods was in low concentration although the high values of this element in industrial liquor cycle. This leads to state that there is some contamination with soil when harvesting and handling the wood. Special care must be taken with both high ash and high mineral elements species, such as Eucalyptus dunnii and Eucalyptus globulus.

  2. Influência da densidade básica da madeira na qualidade da polpa kraft de clones hibrídos de Eucalyptus grandis W. Hill ex Maiden X Eucalyptus urophylla S. T. Blake Effect of wood basic density on kraft pulp quality of hybrid Eucalyptus grandis W. Hill ex Maiden X Eucalyptus urophylla S.T. Blake clones

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    Simone Cristina Setúbal Queiroz

    2004-12-01

    Full Text Available Foram estudados dois clones de Eucalyptus com densidades básicas de 447 e 552 kg/m³. O processo kraft foi utilizado para a produção de celulose, tendo sido aplicadas diferentes cargas de álcali para se obterem polpas com número kappa 18 ± 0,5. As polpas foram branqueadas pela seqüência ODEopDD, a alvuras de 90 ± 1% ISO, e refinadas, sendo suas propriedades físico-mecânicas e ópticas analisadas. A madeira de baixa densidade mostrou-se mais recomendável para a produção de celulose, por ter apresentado maior rendimento depurado, viscosidade da polpa mais elevada, ter requerido menor carga de álcali no cozimento, ter proporcionado menor teor de sólidos no licor residual e menor consumo de reagentes químicos no branqueamento. As propriedades mecânicas e estruturais das polpas não foram afetadas significativamente pela densidade básica das madeiras.Two hybrid Eucalyptus clones having 447 kg/m³ and 552 kg/m³ basic densities were used for this study. The kraft process was used for pulping the wood chips to kappa number 18±0.5 and different alkali charges were applied to reach this delignification target. Pulp was bleached to 90±1% ISO using the ODEopDD bleaching sequence. The bleached pulp was refined and its physical-mechanical properties were determined. The lower density wood was recommended for pulp production due to its lower alkali requirement for pulping, higher screened yield, superior pulp viscosity, lower black liquor solids content and lower bleaching chemical requirement. Wood basic density did not affect significantly the mechanical and structural pulp properties.

  3. Influence of kraft pulping on carboxylate content of softwood kraft pulps

    Science.gov (United States)

    Zheng Dang; Thomas Elder; Arthur J. Ragauskas

    2006-01-01

    This study characterizes changes in fiber charge, which is the carboxylate content of fibers, for two sets of kraft pulps: (1) conventional laboratory cooked loblolly pine kraft pulps and (2) conventional pulping (CK) versus low solids pulping (LS) pulps. Laboratory kraft pulping of loblolly pine was carried out to study the influence of pulping conditions, including...

  4. Kraft pulping and ECF bleaching of Eucalyptus globulus pretreated by the white-rot fungus Ceriporiopsis subvermispora - doi: 10.4025/actascitechnol.v34i3.12410

    Directory of Open Access Journals (Sweden)

    Claudio Salazar

    2012-05-01

    Full Text Available Eucalyptus globulus wood chips were decayed by the lignin-degrading fungus Ceriporiopsis subvermispora as a pretreatment step before kraft pulping. Weight and component losses of wood after the biotreatment were the following: weight (5%, glucans (1.5%, xylans (4.3%, lignin (5.7% and extractives (57.5%. The residual amount of lignin (expressed by the kappa number in pulps from biotreated wood chips was lower than that of pulps from the undecayed control. Depending on the delignification degree, kraft biopulps presented similar or up to 4% increase in pulp yield and 20% less hexenuronic acids (HexA than control pulps. The extended delignification with O2 decreases approximately 50% of the kappa number of the pulps and increases brightness, but had no effect in HexA reduction. The bleaching steps with chlorine dioxide (D0ED1 sequence decreased the kappa number up to 97%, increased pulp brightness up to 84% ISO and decreased HexA amount up to 91%. The use of C. subvermispora in biopulping of E. globulus generated important benefits during the production of kraft pulps that are reflected in a high pulp yield, low residual lignin content, low HexA amount, high brightness and viscosity of the biopulps as compared with pulps produced from untreated wood chips.

  5. Estratégia de análise da qualidade de madeira de Eucalyptus sp. para produção de celulose A laboratory technique to establish Eucalyptus sp. wood quality for kraft pulp production

    Directory of Open Access Journals (Sweden)

    José Lívio Gomide

    2004-06-01

    Full Text Available Estudou-se uma nova técnica laboratorial de análise de qualidade da madeira de Eucalyptus sp. para produção de polpa celulósica kraft. A técnica consiste em realizar, simultaneamente, quatro cozimentos de cavacos utilizando diferentes cargas de álcali ativo para estabelecer a característica de deslignificação da madeira. Pelo uso de equações de regressão, calcula-se o álcali ativo necessário para obter o número kappa desejado, o rendimento, a viscosidade e álcali consumido para o kappa objetivo. Os estudos estatísticos evidenciaram que uma única batelada de quatro cozimentos é suficiente, não sendo necessário realizar repetições.A new laboratory technique was tested to determine Eucalyptus sp. wood quality for kraft pulp production. This technique consists in performing four cooks simultaneously using different active alkali charges to establish the wood delignification characteristics. Based on regression equation it is possible to determine the alkali charge necessary to obtain a desired kappa number and the yield, viscosity and the alkali consumed for the target kappa. Statistical analysis demonstrated that a set of four cooks without replication is sufficient to determine the wood quality characteristics.

  6. Purification and characterization of a cellulase-free, thermostable endo-xylanase from Streptomyces griseorubens LH-3 and its use in biobleaching on eucalyptus kraft pulp.

    Science.gov (United States)

    Wu, Hao; Cheng, Xianbo; Zhu, Yongfeng; Zeng, Wei; Chen, Guiguang; Liang, Zhiqun

    2018-01-01

    Xylanase is an important enzyme involved in degrading xylan. In this study, an extracellular cellulase-free, thermostable endo-xylanase which was produced by Streptomyces griseorubens LH-3 with bagasse semi-cellulose as a carbon source was purified and characterized. The xylanase was purified 4-fold with a recovery yield of 21.6% by precipitation with 25-55% (NH 4 ) 2 SO 4 , Mono Q ion exchange chromatography and sephacryl S-200 HR gel filtration chromatography. It appeared as a monomeric protein on SDS-PAGE gel and had an apparent molecular weight of 45.5 kDa with specific activity of 434 IU/mg. Using birchwood xylan as substrate, the maximum velocity (V max ) and Michaelis-Menten constant (K m ) were found to be 1.44 mg/ml and 2.05 μmol/min mg, respectively. The purified xylanase was active at pH 4.0-8.0 with an optimum pH of 5.0. It was stable at temperatures between 30°C and 50°C, exhibiting maximum activity at 60°C. Hg 2+ and Al 3+ inhibited the enzyme activity significantly. Enzymatic product analysis indicated that the enzyme was an endo-xylanase, whose hydrolysis products were mainly a series of short-chain xylooligosaccharides. Furthermore, it was used for biobleaching of eucalyptus kraft pulp, and results showed that this purified xylanase increased the brightness of the pulp by 14.5% and reduced the kappa number by 24.5%. All these industrially relevant characteristics made it had potential application in the pulp and paper industry as a biobleaching agent. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. Process design and economics of a flexible ethanol-butanol plant annexed to a eucalyptus kraft pulp mill.

    Science.gov (United States)

    Pereira, Guilherme C Q; Braz, Danilo S; Hamaguchi, Marcelo; Ezeji, Thaddeus C; Maciel Filho, Rubens; Mariano, Adriano P

    2018-02-01

    This work proposes a strategy, from a process design standpoint, for pulp companies to enter the Brazilian ethanol market. The flexible plant converts eucalyptus-derived glucose to either ethanol or butanol (according to market conditions) and xylose only to butanol production. Depending on the biomass pretreatment technology, Monte Carlo simulations showed that the Net Present Value (NPV) of the flexible plant increases by 20-28% in relation to an ethanol-dedicated plant. Whereas the lower costs of the steam explosion technology turns the investment more attractive (NPV = 184 MMUSD; IRR = 29%), the organosolv technology provides better flexibility to the plant. This work also shows that excessive power consumption is a hurdle in the development of flash fermentation technology chosen for the flexible plant. These results indicate that conventional batch fermentation is preferable if the enzymatic hydrolysis step operates with solids loading up to 20 wt%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Application of a novel alkali-tolerant thermostable DyP-type peroxidase from Saccharomonospora viridis DSM 43017 in biobleaching of eucalyptus kraft pulp.

    Directory of Open Access Journals (Sweden)

    Wangning Yu

    Full Text Available Saccharomonospora viridis is a thermophilic actinomycete that may have biotechnological applications because of its dye decolorizing activity, though the enzymatic oxidative system responsible for this activity remains elusive. Bioinformatic analysis revealed a DyP-type peroxidase gene in the genome of S. viridis DSM 43017 with sequence similarity to peroxidase from dye-decolorizing microbes. This gene, svidyp, consists of 1,215 bp encoding a polypeptide of 404 amino acids. The gene encoding SviDyP was cloned, heterologously expressed in Escherichia coli, and then purified. The recombinant protein could efficiently decolorize several triarylmethane dyes, anthraquinonic and azo dyes under neutral to alkaline conditions. The optimum pH and temperature for SviDyP was pH 7.0 and 70°C, respectively. Compared with other DyP-type peroxidases, SviDyP was more active at high temperatures, retaining>63% of its maximum activity at 50-80°C. It also showed broad pH adaptability (>35% activity at pH 4.0-9.0 and alkali-tolerance (>80% activity after incubation at pH 5-10 for 1 h at 37°C, and was highly thermostable (>60% activity after incubation at 70°C for 2 h at pH 7.0. SviDyP had an accelerated action during the biobleaching of eucalyptus kraft pulp, resulting in a 21.8% reduction in kappa number and an increase of 2.98% (ISO in brightness. These favorable properties make SviDyP peroxidase a promising enzyme for use in the pulp and paper industries.

  9. Application of a novel alkali-tolerant thermostable DyP-type peroxidase from Saccharomonospora viridis DSM 43017 in biobleaching of eucalyptus kraft pulp.

    Science.gov (United States)

    Yu, Wangning; Liu, Weina; Huang, Huoqing; Zheng, Fei; Wang, Xiaoyu; Wu, Yuying; Li, Kangjia; Xie, Xiangming; Jin, Yi

    2014-01-01

    Saccharomonospora viridis is a thermophilic actinomycete that may have biotechnological applications because of its dye decolorizing activity, though the enzymatic oxidative system responsible for this activity remains elusive. Bioinformatic analysis revealed a DyP-type peroxidase gene in the genome of S. viridis DSM 43017 with sequence similarity to peroxidase from dye-decolorizing microbes. This gene, svidyp, consists of 1,215 bp encoding a polypeptide of 404 amino acids. The gene encoding SviDyP was cloned, heterologously expressed in Escherichia coli, and then purified. The recombinant protein could efficiently decolorize several triarylmethane dyes, anthraquinonic and azo dyes under neutral to alkaline conditions. The optimum pH and temperature for SviDyP was pH 7.0 and 70°C, respectively. Compared with other DyP-type peroxidases, SviDyP was more active at high temperatures, retaining>63% of its maximum activity at 50-80°C. It also showed broad pH adaptability (>35% activity at pH 4.0-9.0) and alkali-tolerance (>80% activity after incubation at pH 5-10 for 1 h at 37°C), and was highly thermostable (>60% activity after incubation at 70°C for 2 h at pH 7.0). SviDyP had an accelerated action during the biobleaching of eucalyptus kraft pulp, resulting in a 21.8% reduction in kappa number and an increase of 2.98% (ISO) in brightness. These favorable properties make SviDyP peroxidase a promising enzyme for use in the pulp and paper industries.

  10. Extraction of hemicellulose from South African eucalyptus grandis using weak white liquor activation technology and its impact on kraft pulping efficiency

    CSIR Research Space (South Africa)

    Johakimu, Jonas K

    2017-09-01

    Full Text Available , near neutral pH during woodchips activation, a short wood activation time (15 min), and weak white liquor to water ratio of 20:80 is required. The concentration of hemicelluloses in the extract was approximately 2.0 g/L. During kraft pulping, weak white...

  11. Methanol-based pulping of Eucalyptus globulus

    Energy Technology Data Exchange (ETDEWEB)

    Gilarranz, M.A.; Oliet, M.; Rodriguez, F.; Tijero, J. [Universidad Complutense de Madrid, Madrid (Spain). Dept. de Ingenieria Quimica

    1999-06-01

    The dissolution of wood components using organosolv pulping was discussed. Solvents such as ethanol and methanol can provide more efficient utilization of the lignocellulosic feedstock, ease of bleachability, and lower capital production costs compared to the kraft process. In this study, the autocatalyzed pulping of Eucalyptus globulus wood in a methanol-water media was examined. The influence of pulping temperature, pulping time and methanol concentration on pulp properties were determined by a surface response method. One of the advantages of using methanol pulping of hardwoods compared to ethanol pulping is the low boiling point of methanol which makes its recovery easy from pulping black liquor by distillation. The price of methanol is also very low compared to other solvents. The optimum pulping conditions were found to be a cooking temperature of 185 degrees C, a cooking time of 110 minutes and a methanol concentration of 50 per cent. These conditions yielded a pulp with a low kappa number and a viscosity value of 110 mL/g. When ethanol pulping was used under the same conditions, the resulting pulp had a higher kappa number and a lower viscosity. 27 refs., 2 tabs., 8 figs.

  12. Kraft pulping of industrial wood waste

    Science.gov (United States)

    Aziz. Ahmed; Masood. Akhtar; Gary C. Myers; Gary M. Scott

    1998-01-01

    Most of the approximately 25 to 30 million tons of industrial wood waste generated in the United States per year is burned for energy and/or landfilled. In this study, kraft pulp from industrial wood waste was evaluated and compared with softwood (loblolly pine, Douglas-fir) and hardwood (aspen) pulp. Pulp bleachability was also evaluated. Compared to loblolly pine...

  13. An environmental systems analysis of the Kraft pulp industry in Thailand

    NARCIS (Netherlands)

    Warit, J.

    2006-01-01

    The pulp industry inThailandis of economic and social importance because of its production value, the revenues from export and the employment in this sector. The eucalyptus-based Kraft pulp industry plays an

  14. EFFECTS OF XYLAN IN EUCALYPTUS PULP PRODUCTION

    Directory of Open Access Journals (Sweden)

    Bianca Moreira Barbosa

    2016-06-01

    Full Text Available The search for a better use of wood in the pulp industry has fuelled interest in a more rational use of its components, particularly xylans. The impact of xylans removal and of xylans redeposition on pulp properties for tissue and P&W paper grades are discussed in this paper. Kraft pulp (15.6% xylans treatment with 10-70 g.L-1 NaOH resulted in pulps of 14.5-5.9% xylans. The treatments decreased pulp lignin and HexA contents and caused significant positive impact on subsequent oxygen delignification and ECF bleaching. Xylan removal decreased pulp beatability, water retention value and tensile index but increased drainability, water absorption capacity, capillarity Klemm and bulk. Overall, xylan depleted pulps showed almost ideal properties for tissue paper grade pulps. In a second step of the research, xylans extracted from unbleached (BXL and bleached eucalyptus pulps (WXL by cold caustic extraction (CCE were added to a commercial brown pulp in the oxygen delignification (O-stage and further bleached. Xylans deposition occurred at variable degree (up to 7% on pulp weight depending upon the O-stage reaction pH. Pulp bleachability was not impaired by WXL xylan deposition but slightly negatively affected by BXL xylans. Pulp beatability was improved by xylan deposition. The deposited xylans were quite stable across bleaching and beating, with the WXL xylans being more stable than the BXL ones. At low energy consumption, the deposited xylans improved pulp physical and mechanical properties. Xylans extraction by CCE with subsequent deposition onto pulp in the O-stage proved attractive for manufacturing high xylan P&W paper grades.

  15. Kinetic modeling of kraft delignification of Eucalyptus globulus

    Energy Technology Data Exchange (ETDEWEB)

    Santos, A.; Rodriguez, F.; Gilarranz, M.A.; Moreno, D.; Garcia-Ochoa, F. [Univ. Complutense, Madrid (Spain). Dept. de Ingenieria Quimica

    1997-10-01

    A kinetic model for the kraft pulping delignification of Eucalyptus globulus is proposed. This model is discriminated among some kinetic expressions often used in the literature, and the kinetic parameters are determined by fitting of experimental results. A total of 25 isothermal experiments at liquor-to-wood ratios of 50 and 5 L/kg have been carried out. Initial, bulk, and residual delignification stages have been observed during the lignin removal, the transitions being, referring to the lignin initial content, about 82 and 3%. Carbohydrate removal and effective alkali-metal and hydrosulfide consumption have been related with the lignin removal by means of effective stoichiometric coefficients for each stage, coefficients also being calculated by fitting of the experimental data. The kinetic model chosen has been used to simulate typical kraft pulping experiments carried out at nonisothermal conditions, using a temperature ramp. The model yields simulated values close to those obtained experimentally for the wood studied and also ably reproduces the trends of the literature data.

  16. Reactivity of syringyl and guaiacyl lignin units and delignification kinetics in the kraft pulping of Eucalyptus globulus wood using Py-GC-MS/FID.

    Science.gov (United States)

    Lourenço, Ana; Gominho, Jorge; Marques, António Velez; Pereira, Helena

    2012-11-01

    Eucalyptus globulus sapwood and heartwood showed no differences in lignin content (23.0% vs. 23.7%) and composition: syringyl-lignin (17.9% vs. 18.0%) and guaiacyl-lignin (4.8% vs. 5.2%). Delignification kinetics of S- and G-units in heartwood and sapwood was investigated by Py-GC-MS/FID at 130, 150 and 170°C and modeled as double first-order reactions. Reactivity differences between S and G-units were small during the main pulping phase and the higher reactivity of S over G units was better expressed in the later pulping stage. The residual lignin composition in pulps was different from wood or from samples in the initial delignification stages, with more G and H-units. S/G ratio ranged from 3 to 4.5 when pulp residual lignin was higher than 10%, decreasing rapidly to less than 1. The S/H was initially around 20 (until 15% residual lignin), decreasing to 4 when residual lignin was about 3%. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Preventing Strength Loss of Unbleached Kraft Pulp

    Energy Technology Data Exchange (ETDEWEB)

    Martin Hubbe; Richard Venditti; John Heitmann

    2003-04-16

    Kraft pulp fibers lose inter-fiber bonding ability when they are dried during the manufacture of paper. Adverse environmental consequences of this loss include (a) limitations on the number of times that kraft fibers can be recycled, (b) reduced paper strength, sometimes making it necessary to use heavier paper or paperboard to meet product strength requirements, increasing the usage of raw materials, (c) decreased rates of paper production in cases where the fiber furnish has been over-refined in an attempt to regain inter-fiber bonding ability. The present study is the first of its type to focus on unbleached kraft fibers, which are a main ingredient of linerboard for corrugated containers. About 90 million tons of unbleached kraft fiber are used worldwide every year for this purpose.

  18. Kinetics of Strong Acid Hydrolysis of a Bleached Kraft Pulp for Producing Cellulose Nanocrystals (CNCs)

    Science.gov (United States)

    Qianqian Wang; Xuebing Zhao; J.Y. Zhu

    2014-01-01

    Cellulose nanocrytals (CNCs) are predominantly produced using the traditional strong acid hydrolysis process. In most reported studies, the typical CNC yield is low (approximately 30%) despite process optimization. This study investigated the hydrolysis of a bleached kraft eucalyptus pulp using sulfuric acid between 50 and 64 wt % at temperatures of 35−80 °C...

  19. Biobleaching of oxygen delignified kraft pulp by several white rot fungal strains.

    NARCIS (Netherlands)

    Moreira, M.T.; Feijoo, G.; Sierra-Alvarez, R.; Lema, J.; Field, J.A.

    1997-01-01

    Twenty-five white rot fungal strains were tested for their ability to bleach Eucalyptus globulus oxygen delignified kraft pulp (OKP). Under nitrogen-limited culture conditions, eight outstanding biobleaching strains were identified that increased the brightness of OKP by more than 10 ISO units

  20. Utilización de Eucalyptus spp. Alternativas de plantaciones uruguayas para pulpa Kraft

    Directory of Open Access Journals (Sweden)

    Javier Doldán

    2011-05-01

    Full Text Available Las plantaciones de Eucalyptus globulus han mostrado desiguales tasas de crecimiento en diferentes regiones de Uruguay. Esto ha motivado la búsqueda de otros orígenes de semilla y especies para la producción de pulpa de celulosa. Propiedades papeleras de las pulpas blanqueadas (ECF de especies alternativas llevan a intuir que podrían ser atractivas para mercados de pulpa de fibra corta. En este trabajo se realiza un comparativo del E. grandis, E. dunnii, E. maidenii y E. globulus (procedencia de semilla “Jeeralang” con el E. globulus predominante en Uruguay. Se discute el potencial de estas maderas como base para una mezcla en cocción, basándose en el análisis de propiedades físicas (densidad aparente básica, propiedades pulpables (rendimiento, carga de álcali activo en cocción Kraft y consumo de madera y propiedades papeleras. En trabajos previos se han encontrado diferencias significativas entre el comportamiento pulpable del Eucalyptus globulus y Eucalyptus maidenii, sugiriendo que nosería recomendable mezclar estas especies. La misma conclusión se podría extender a las especies de Eucalyptus estudiadas. Sin embargo, teniendo en cuenta los similares requerimientos en las cargas de álcali activo, la mezcla entre especies alternativas podría ser aplicada.AbstractEucalyptus globulus plantations have shown different growth rates in different sites in Uruguay. This fact has triggered the search for other pulp wood species and seed provenance. Paper making properties of ECF bleached pulps of alternative speciessuggest that these species could be perfectly used as hardwood bleached pulp raw materials. This study intends to compare alternativeUruguayan pulpwood species E. grandis, E. dunnii, E. maidenii and “Jeeralang” a seed provenance of E. globulus to the E. globulus most widely cultivated in the country. Physical properties of wood (Basic Density, Kraft pulping performance (pulp yield, active alkali and wood consumption

  1. Anthraquinone effect on kraft cooking curve for the wood of Eucalyptus grandis x Eucalyptus urophylla hybrid

    Directory of Open Access Journals (Sweden)

    Magnos Alan Vivian

    2017-12-01

    Full Text Available This study aimed to evaluate the effects of anthraquinone addition in the cooking curve, with different loads of reagents, through the kraft pulping process, of Eucalyptus grandis x Eucalyptus urophylla wood, to infer about the process parameters. The wood was transformed into chips and classified to conduct the kraft cooking curves. The applied loads were from 10% to 24% of active alkali, with an anthraquinone charge of 0.05% (on dry wood. We evaluated raw and screened yield, reject content, kappa number (delignification level and residual active alkali. We observed that the addition of anthraquinone did not affect the process raw yield, but increased the screened yield by reducing reject content, especially for low loads of active alkali (10% and 12%. Another effect observed was the reduction of the kappa number with the addition of anthraquinone, which indicates the increase of the wood delignification rate. This is reinforced by the lower residual active alkali, which implies greater use of reagents in the process.

  2. Utilização de surfactantes, na polpação kraft de madeira de eucalipto, como auxiliar na remoção de extrativos lipofílicos Surfactant utilization in kraft pulping of eucalyptus wood to improve lipophilic extractives removal

    Directory of Open Access Journals (Sweden)

    Deusanilde de Jesus Silva

    2004-12-01

    Full Text Available Problemas de deposição de "pitch" em fábricas de celulose e de papel são atribuídos aos extrativos lipofílicos existentes na madeira. Uma das maneiras mais eficientes de controlar essa deposição é através da remoção de seus precursores do sistema, logo que possível, nas etapas de cozimento, lavagem da polpa marrom e pré-deslignificação com oxigênio. O uso de surfactantes como aditivos da polpação tem sido investigado, mas há grande deficiência de informações técnicas, e a aplicação industrial é, ainda, incipiente. A proposta deste trabalho foi analisar a viabilidade de minimizar a deposição de "pitch", intensificando a remoção de suas substâncias precursoras na etapa de polpação pelo uso de tensoativos sintéticos com propriedades umectantes e solubilizantes. Foram testados 20 princípios ativos de surfactantes em cozimento kraft convencional de madeira de eucalipto. Os resultados, alguns estatisticamente significativos, apontaram redução do teor de substâncias lipofílicas na polpa marrom. Foi observado que a remoção dos extrativos lipofílicos da madeira é afetada, inversamente, pelo teor de óxido de eteno na molécula do surfactante. Outros parâmetros de cozimento, como deslignificação, rendimento, teor de rejeitos e viscosidade da polpa, foram também avaliados.Extractives are pitch precursors and may decrease pulping efficiency and affect pulp quality. Probably, the most efficient way to minimize pitch problems is to remove their precursors from the system during cooking, pulp washing and oxygen delignification. Use of surfactants as pulping additives has been investigated but technical information is deficient and industrial application is very incipient. The objective of this study was to analyze the performance of different surfactants as additives for kraft pulping of Eucalyptus wood. Twenty surfactants with different basic chemical structures were used. The results demonstrated that

  3. Catalysis: A Potential Alternative to Kraft Pulping

    Science.gov (United States)

    Alan W. Rudie; Peter W. Hart

    2014-01-01

    A thorough analysis of the kraft pulping process makes it obvious why it has dominated for over a century as an industrial process with no replacement in sight. It uses low-cost raw materials; collects and regenerates over 90% of the chemicals needed in the process; and is indifferent to wood raw material and good at preserving the cellulose portion of the wood, the...

  4. Air pollution control in kraft pulp mills.

    Science.gov (United States)

    Bhatia, S P; de Souza, T L; Azarniouch, M K; Prahacs, S

    1978-02-01

    A patented gas scrubbing process, whereby the emissions of malodorous reduced sulphur compounds are effectively and economically reduced, is described. Stack gases are scrubbed with an alkaline suspension of activated carbon. Reduced sulphur compounds as well as sulphur oxides are converted to sodium salts which are subsequently recovered and utilized for pulping. The process also reduces particulate emissions. It does not produce subsequent waste disposal problems and has little or, in some cases, zero net cost, on account of the simultaneous recovery of heat and chemicals. Furthermore, the paper also reviews some innovations made in gas chromatography techniques, for the measurement of trace quantities of sulphur compounds present in kraft mill emissions.

  5. The effects of high energy radiation on the pulping properties of Pinus radiation and Eucalyptus regnans

    International Nuclear Information System (INIS)

    McLaren, K.G.; Garland, C.P.; Higgins, H.G.

    1976-01-01

    Studies have been made of the effects of high energy radiation on the pulping behaviour of Eucalyptus regnans and Pinus radiata. Pre-irradiation of wood chips with small doses of 60 Co gamma radiation (up to about 0.2 Mrad) caused little degradation of the cellulose, and had only minor effects on the kraft pulping properties of both wood species. Pulp yield, Kappa number and strength properties of the pulps showed little change. There was also little effect on the bisulphite cooking of Pinus radiata. As the dose was increased to 1 Mrad, degradation of cellulose (as indicated by degree of polymerisation measurements) became significant, and Kraft pulp yields from both woods showed small reductions. The Kappa number and physical properties of these pulps were little affected at this dose level. A gamma radiation dose of 10 Mrad produced marked depolymerisation of the cellulose, and big reductions in kraft and neutral sulphite semi-chemical pulp yields. The kraft pulps showed a much higher lignin content. Some low dose (0.15 Mrad) irradiations on thin chips were carried out with a 1 MeV electron accelerator. In contrast to comparable gamma irradiations, this treatment produced discernible changes in kraft pulping behaviour. The pulp yield, under the same cooking conditions, appears to be slightly higher, but the Lignin content of the pulp was increased. (Author)

  6. WOOD BASIC DENSITY EFFECT OF Eucalyptus grandis x Eucalyptus urophylla CLONES ON BLEACHED PULP QUALITY

    Directory of Open Access Journals (Sweden)

    Sheila Rodrigues dos Santos

    2010-08-01

    Full Text Available The study analyzed the wood basic density effect in two Eucalyptus grandis x Eucalyptus urophylla hybrid clones (440 kg/m3 e 508 kg/m3 on bleached pulp quality (fiber dimensions and physical-mechanical properties. The woods performance on pulping, bleaching and beating results were analyzed. The Kraft pulping was carried out in forced circulation digester in order to obtain 17±1 kappa number targets. The pulps were bleached to 90±1 using delignification oxygen and D0EOPD1 bleaching sequence. Bleached pulp of low basic density clone showed, significantly, lowest revolutions number in the PFI mill to reach tensile index of 70 N.m/g, low Schopper Riegler degree and generated sheets with higher values to bulk and opacity. These characteristics and properties allow concluding that bleached pulp of low basic density clone was the most indicated to produce printing and writing sheets. The bleached pulp of high basic density clone showed higher values of bulk and capillarity Klemm and lower water retention value when analyzed without beating. The bleached pulp of high basic density clone showed more favorable characteristics to the production of tissue papers.

  7. Pulp and paper production from Spruce wood with kraft and ...

    African Journals Online (AJOL)

    Picea orientalis) wood collected from the Black Sea Region of Turkey. Fiber properties, carbohydrate contents, strength and optical properties of resultant paper were included to determine the properties of these pulp samples. Optimum kraft ...

  8. POLPAÇÃO KRAFT E KRAFT/AQ DA MADEIRA PRÉ-HIDROLISADA DE HÍBRIDO DE Eucalyptus urophylla x grandis

    Directory of Open Access Journals (Sweden)

    Rafael dos Santos

    2016-01-01

    Full Text Available The wood of the gender Eucalyptus occupies a prominence place among other cellulose sources due to its chemical composition, its low cost, abundance and availability. Among the chemical pulping processes, kraft process is the most extensively one used for the production of cellulosic pulps starting from eucalyptus wood. The anthraquinone (AQ usage in the pulping has as main purposes to increase the delignification rate as well as to protect the pulp from the carbohydrate degradation. The present work has aimed to use the anthraquinone as an addictive in the cooking seeking to reduce the load of applied sulphidity without harming the quality of the pulp. The kraft and kraft/AQ cooking were accomplished in rotative laboratorial digester being varied the active alkali initially (10, 13, 16 and 19% and, later, the sulphidity (5, 10, 15, 20 and 25%, maintaining the other conditions constant aiming to obtain pulp with kappa number close to nine. Starting from the variation of the active alkali and of the sulphidity, delignification curves were established between active alkali and kappa number and, sulphidity and kappa number, where it was possible to establish the minimum necessary amounts of alkali, as well as of the sulphidity. Starting from the cooking, it was possible to establish the active alkali and sulphidity loads of 17,4% and 8,8%, respectively. The cooking to the certain conditions presented screened yield of 48,63%, and the yield based on the initial mass of wood was of 42,24%, obtaining a high quality pulp, in other words, with low number kappa and hemicelluloses tenor (0,41% and high tenor of alpha cellulose (98,49%.

  9. Laccase for biobleaching of eucalypt kraft pulp by means of a modified industrial bleaching sequence.

    Science.gov (United States)

    Moldes, D; Vidal, T

    2012-01-01

    Biobleaching of kraft pulp is a possible application of laccase, but it has not been described in detail for complete industrial bleaching sequences yet. Therefore, in this work, the biobleaching of Eucalyptus globulus kraft pulp was performed using a modified industrial totally chlorine-free sequence. The modification consisted in the substitution of an enzymatic delignification stage, based on the application of laccase from Trametes villosa, for the first alkaline extraction one. The enzymatic stage was performed with several synthetic and natural mediators, namely 1-hydroxybenzotriazole (HBT), violuric acid (VA), methyl syringate, and syringaldehyde. Several pulp properties were analyzed after each stage of the bleaching process--kappa number, ISO brightness, viscosity, and optical properties of CIEL*a*b* system. The new biobleaching sequence improved the pulp properties, in comparison to the conventional bleaching sequence, if HBT or VA was used as mediators. VA was selected as the best mediator of those tested and the effect of its concentration in the enzymatic stage was subsequently studied. Reducing the initial concentration by 30%, the same pulp quality was obtained, but if the reduction attained 60%, an important decrease in pulp integrity was detected. The modified bleaching sequence could improve the bleached pulp properties (kappa number 10%, ISO brightness 1%, and viscosity 5%) in comparison to the mill sequence. Copyright © 2012 American Institute of Chemical Engineers (AIChE).

  10. Kraft pulp from budworm-infested jack pine

    Science.gov (United States)

    J. Y. Zhu; Gary C. Myers

    2006-01-01

    This study evaluated the quality of kraft pulp from bud-worm-infested jack pine. The logs were classified as merchantable live, suspect, or merchantable dead. Raw materials were evaluated through visual inspection, analysis of the chemical composition, SilviScan measurement of the density, and measurement of the tracheid length. Unbleached pulps were then refined using...

  11. ANTHRAQUINONE ADDITION IN THE ALKALINE PULPING OF Eucalyptus saligna

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Jerônimo

    2009-10-01

    Full Text Available The present work evaluated different alkaline pulping conditions for Eucalyptus saligna wood. The objective was to evaluate the influence of the anthraquinone (AQ on the reduction of the total reduced sulfur (TRS in the aerial emissions, by reducing the sulfidity. The experiment consisted of 8 cooking with active alkali varying from  19 to 21%, sulfidity from  0 to 20% and anthraquinone from 0 to 0.1%, aiming to obtain  kappa numbers in the range 15.5±1.5. The H factor was used to control the relation time/temperature along cooking. The addition of anthraquinone increased the delignification rate allowing sulfidity reduction. The kraft/AQ pulping with sulfidities of 5 and 10% presented satisfactory results, making it possible the replacement of conventional kraft cooking, giving a reduction in process sulfidity without harms in pulping. In spite of a slightly lower performance, the soda/AQ cooking has potential to be used where the smell is a critical problem in the industrial operation.

  12. Reducing sugar production of sweet sorghum bagasse kraft pulp

    Science.gov (United States)

    Solihat, Nissa Nurfajrin; Fajriutami, Triyani; Adi, Deddy Triyono Nugroho; Fatriasari, Widya; Hermiati, Euis

    2017-01-01

    Kraft pulping of sweet sorghum bagasse (SSB) has been used for effective delignification method for cellulose production. This study was conducted to evaluate the performance pulp kraft of SSB for reducing sugar production. The study intended to investigate the effect of active alkali and sulfidity loading variation of SSB pulp kraft on reducing sugar yield per biomass. The SSB pulp was prepared after pulping using three variations of active alkali (17, 19, and 22%) and sulfidity loading (20, 22, and 24%) at 170°C for 4 h with liquor to wood ratio of 10. A total of 9 pulps were obtained from these pretreatments. Delignification pretreatment has been succesfully removed lignin and hemicellulose more than 90% and 50%, respectively. Increasing active alkali and sulfidity loading has significantly increased lignin removal caused by disruption of the cell wall structure for releasing lignin into black liquor in the cellulose extraction. The enzymatic hydrolysis of pulp was carried out with cellulase loading of 40 FPU per g substrate in the shaking incubator at 50°C and 150 rpm for 78 h. For each 24 h, the reducing sugar yield (DNS assay) has been observed. Even though the lignin and hemicellulose loss occurred along with higher active alkali loading, this condition tends to decrease its yield. The reducing sugar concentration varied between 7-8 g/L. Increasing active alkali and sulfidity was significantly decreased the reducing sugar per biomass. Pulp delignified by 17% active alkali and 20% sulfidity has demonstrated the maximum reducing sugar yield per biomass of 45.57% resulted after 72 h enzymatic hydrolysis. These results indicated that kraft pulping was success to degrade more lignin and hemicellulose content to facilitate the enzyme for breaking down the cellulose into its sugar monomer. A high loss of lignin and hemicellulose are not single factor to improve digestibility of SSB. This sugar has potential for yeast fermented into bioethanol.

  13. Efeito do teor de lignina da madeira de Eucalyptus globulus Labill. no desempenho da polpação kraft

    Directory of Open Access Journals (Sweden)

    Gabriel Valim Cardoso

    2011-01-01

    Full Text Available In this research, it was analyzed the lignin content effect of Eucalyptus globulus Labill. wood in kraft pulping optimization. Seventy-two laboratory cooking were made with wood chips obtained from six Eucalyptus globulus trees selected from a group of 50 trees. The wood chips from three trees with the lowest lignin content, with average 20.53%, were mixed proportionally based on the tree weights, obtaining the sample of low lignin content wood. The same was made to obtain the sample for wood chips with the highest lignin content, with average 23.02%. The two lignin levels were statistically different. The two wood samples had basic densities statistically not different. Using three maximum temperatures levels (160, 165 and 170ºC, and three active alkali charged (17, 18.5 and 20%, the wood chips were converted to kraft pulps. The pulps were then characterized to analyze the influence of the distinct treatments employed in the cooking on their properties. The effect of the cooking conditions was expressed by mathematical models in order to determine the optimum points for each of the evaluated properties. The optimization process indicated maximum temperature of 168ºC, and active alkali of 19%, for maximum kraft pulping yield to achieve kappa number 18; this result was for woods with low lignin content. For woods containing the high lignin content, the optimization showed maximum cooking temperature of 169ºC and active alkali of 19% for kappa number of 18. The average reduction of 2.49% in wood lignin content resulted a correspondent gain of 2.2% in the kraft yield (o.d. basis and a reduction on the active alkali charge of 1.2% (o.d. basis to achieve kappa numbers from 16 to 19, preserving pulp properties. If the option is to work with kappa number 19 instead of 16, the gain in kraft yield is approximately 2%. Therefore, when working with low lignin content wood and kappa number 19 instead of 16, a substantial gain of approximately 4.2% is

  14. Delignification of wood and kraft pulp with polyoxometalates

    Science.gov (United States)

    Edward L. Springer; Richard S. Reiner; Ira A. Weinstock; Rajai H. Atalla; Michael W. Wemple; Elena M. G. Barbuzzi

    1998-01-01

    Finely divided aspen and spruce woods and a high lignin pine kraft pulp have been selectively delignified to low lignin levels using aqueous solutions of polyoxometalates under anaerobic conditions. The reduced polyoxometalates in the solutions can be reoxidized with oxygen and act as wet oxidation catalysts for the mineralization of the solubilized lignin and...

  15. Measurement of cellulose content, Kraft pulp yield and basic density ...

    African Journals Online (AJOL)

    Previous descriptions of multisite and multispecies near infra-red (NIR) spectroscopic calibrations for predicting cellulose content (CC) and Kraft pulp yield (KPY) in eucalypt woodmeal demonstrated that large, single calibrations provide precise predictions for a wide range of sites and species. These have since been used ...

  16. The Kraft Pulp And Paper Properties of Sweet Sorghum Bagasse (Sorghum bicolor L Moench

    Directory of Open Access Journals (Sweden)

    Widya Fatriasari

    2015-05-01

    Full Text Available This study investigated the potency of sweet sorghum (Sorghum bicolor bagasse as raw material for pulp and paper using kraft pulping. The effects of alkali and sulfidity loading on kraft pulp and paper properties were also investigated. The pulping condition of the kraft pulp consisted of three levels of alkali loading (17, 19 and 22% and sulfidity loading (20, 22 and 24%. The maximum cooking temperature was 170°C for 4 h with a liquid to wood ratio of 10:1. Kraft pulping of this Numbu bagasse produced good pulp indicated by high screen yield and delignification selectivity with a low Kappa number (< 10. The unbleached pulp sheet produced a superior brightness level and a high burst index. The increase of active alkali loading tended to produce a negative effect on the pulp yield, Kappa number and paper sheet properties. Therefore, it is suggested to use a lower active alkaline concentration.

  17. Effect of plantation density on kraft pulp production from red pine (Pinus resinosa Ait.)

    Science.gov (United States)

    J.Y. Zhu; G.C. Myers

    2006-01-01

    Red pine (Pinus resinosa Ait.) butt logs from 38 year old research plots were used to study the effect of plantation stand density on kraft pulp production. Results indicate that plantation stand density can affect pulp yield, unrefined pulp mean fibre length, and the response of pulp fibre length to pulp refining. However, the effect of plantation stand density on...

  18. Application of thermoalkalophilic xylanase from Arthrobacter sp. MTCC 5214 in biobleaching of kraft pulp

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    released by enzyme treatment showed a characteristic peak at 280 nm indicating the presence of lignin in the released coloring matter. Enzymatic prebleaching of kraft pulp showed 20 % reduction in kappa number of the pulp without much change in viscosity...

  19. Producing a True Lignin Depolymerase for Biobleaching Softwood Kraft Pulp

    Energy Technology Data Exchange (ETDEWEB)

    Simo Sarkanen

    2002-02-04

    This project constituted an intensive effort devoted to producing, from the white-rot fungus Tramets Cingulata, a lignin degrading enzyme (lignin depolymerase) that is directly able to biobleach or delignify softwood kraft pulp brownstock. To this end, the solutions in which T. cingulata was grown contained dissolved kraft lignin which fulfilled two functions; it behaved as a lignin deploymerase substrate and it also appeared to act as an inducer of enzyme expression. However, the lignin depolymerase isoenzymes (and other extracellular T. cingulata enzymes) interacted very strongly with both the kraft lignin components and the fungal hypae, so the isolating these proteins from the culture solutions proved to be unexpectedly difficult. Even after extensive experimentation with a variety of protein purification techniques, only one approach appeared to be capable of purifying lignin depolymerases to homogeneity. Unfortunately the procedure was extremely laborious; it involved the iso electric focusing of concentrated buffer-exchanged culture solutions followed by electro-elution of the desired protein bands from the appropriate polyacrylamide gel segments

  20. Dry Kraft Pulping at Ambient Pressure for Cost Effective Energy Saving and Pollution Deduction

    Energy Technology Data Exchange (ETDEWEB)

    Yulin Deng; Art Ragauskas

    2012-08-28

    Sponsored by the DOE Industrial Energy Efficiency Grand Challenge program, our research team at the Georgia Institute of Technology conducted laboratory studies and confirmed the concept of making wood pulp using a dry pulping technology. This technology is a new process different from any prior pulping technology used in Kraft and CTMP pulping. Three different kinds of dry pulping methods were investigated. (a) Dry Pulping at Atmospheric Pressure: The first one is to dry and bake the pretreated woodchips in a conventional oven at atmospheric pressure without the use of a catalyst. (b) Dry Pulping at Reduced Pressure: The second method is to dry the pretreated woodchips first in a vacuum oven in the presence of anthraquinone (AQ) as a pulping catalyst, followed by baking at elevated temperature. (c) Liquid Free Chemical Pulping, LFCP. The third method is to first remove the free water of pretreated woodchips, followed by dry pulping using a conventional Kraft pulping digester with AQ and triton as additives. Method one: Experimental results indicated that Dry Pulping at Atmospheric Pressure could produce pulp with higher brightness and lower bulk than conventional Kraft pulp. However, tensile strength of the acquired pulp is much lower than traditional Kraft pulp, and their Kappa number and energy consumption are higher than conventional Kraft pulp. By fully analyzing the results, we concluded that wood fibers might be damaged during the drying process at elevated temperature. The main reason for wood fiber damage is that a long drying time was used during evaporation of water from the woodchips. This resulted in an un-uniform reaction condition on the woodchips: the outside layer of the woodchips was over reacted while inside the woodchips did not reacted at all. To solve this problem, dry pulping at reduced pressure was investigated. Method two: To achieve uniform reaction throughout the entire reaction system, the water inside the pretreated woodchips was

  1. Lignin modification in the initial phase of softwood kraft pulp delignification with polyoxometalates (POMs)

    Science.gov (United States)

    Biljana Bujanovic; Sally A. Ralph; Richard S. Reiner; Rajai H. Atalla

    2007-01-01

    Commercial softwood kraft pulp with kappa number 30.5 (KP30.5) was delignified with polyoxometalates (POM, Na5(+2)[SiV1(-0.1)MoW10(+0.1)O40]), and POM-treated kraft pulp of kappa number 23.6 was obtained (KPPOM,23.6). Residual lignin from pulps was isolated by mild acid hydrolysis and characterized by analytical and spectral methods to gain insight into lignin...

  2. Effects of ozone on kraft process pulp mill effluent

    International Nuclear Information System (INIS)

    Mohammed, A.; Smith, D.W.

    1992-01-01

    Effluent from a kraft process pulp mill was studied in a batch reactor for ozone doses between 50 and 200 mg O 3 /L to identify the suitability of ozone application locations in the treatment process and see the improvements in biotreatability of wastewaters from a kraft process pulp mill. Laboratory acclimatized seed were used for (Biochemical Oxygen Demand) BOD tests for ozonated and unozonated samples. The inhibitory effects were minimized by using optimum dilutions. The studies were divided into three major sections: characterization of mill effluent; ozone system calibration, and reactor design; and ozonation of mill effluent. Seed for BOD tests were acclimatized in batch units for primary, bleach and secondary effluents separately. The results were analyzed using the open-quote t close-quote test for paired experiments and an ANOVA table for statistical confirmation. Residuals were plotted to check the assumptions of constant variance and normal distribution. It was concluded that ozone is most effective for the removal of color and the increase of BOD in secondary effluent. 21 refs., 9 figs., 7 tabs

  3. Ecotoxicological studies with newly hatched larvae of Concholepas concholepas (Mollusca, Gastropoda): bioassay with secondary-treated kraft pulp mill effluents.

    Science.gov (United States)

    Manríquez, Patricio H; Llanos-Rivera, Alejandra; Galaz, Sylvana; Camaño, Andrés

    2013-12-01

    The Chilean abalone or "loco" (Concholepas concholepas, Bruguière 1789) represent the most economically important marine recourse exploited from inner inshore Management and Exploitation Areas for Benthic Resources along the Chilean coast. In this study, newly-hatched larvae of C. concholepas were investigated as a potential model species for marine ecotoxicological studies. The study developed a behavioral standard protocol for assessing the impact that kraft pulp mill effluents after secondary treatment have on C. concholepas larvae. Under controlled laboratory conditions, newly-hatched larvae were exposed to a series of different concentrations of kraft pulp mill effluents with secondary treatment (Pinus spp. and Eucalyptus spp.), potassium dichromate as standard reference toxicant and effluent-free control conditions. Regardless of the type of effluent the results indicated that diluted kraft pulp effluent with secondary treatment had reduced effect on larval survival. Low larval survivals were only recorded when they were exposed to high concentrations of the reference toxicant. This suggests that C. concholepas larval bioassay is a simple method for monitoring the effects of kraft pulp mill effluents with secondary treatment discharged into the sea. The results indicated that dilution of ca. 1% of the effluent with an elemental chlorine free (ECF) secondary treatment is appropriate for achieving low larval mortalities, such as those obtained under control conditions with filtered seawater, and to minimize their impact on early ontogenetic stages of marine invertebrates such as newly-hatched larvae of C. concholepas. The methodological aspects of toxicological testing and behavioral responses described here with newly-hatched larvae of C. concholepas can be used to evaluate in the future the potential effects of other stressful conditions as other pollutants or changes in seawater pH associated with ocean acidification. © 2013 Elsevier Inc. All rights

  4. Effects of tertiary treatment by fungi on organic compounds in a kraft pulp mill effluent.

    Science.gov (United States)

    Rocha-Santos, Teresa; Ferreira, Filipe; Silva, Lurdes; Freitas, Ana Cristina; Pereira, Ruth; Diniz, Mário; Castro, Luísa; Peres, Isabel; Duarte, Armando Costa

    2010-05-01

    Pulp and paper mills generate a plethora of pollutants depending upon the type of pulping process. Efforts to mitigate the environmental impact of such effluents have been made by developing more effective biological treatment systems in terms of biochemical oxygen demand, chemical oxygen demand, colour and lignin content. This study is the first that reports an evaluation of the effects of a tertiary treatment by fungi (Pleurotus sajor caju, Trametes versicolor and Phanerochaete chrysosporium and Rhizopus oryzae) on individual organic compounds of a Eucalyptus globulus bleached kraft pulp and paper mill final effluent after secondary treatment (final effluent). The tertiary treatment with P. sajor caju, T. versicolor and P. chrysosporium and R. oryzae was performed in batch reactors, which were inoculated with separate fungi species and monitored throughout the incubation period. Samples from effluent after secondary and after tertiary treatment with fungi were analysed for both absorbance and organic compounds. The samples were extracted for organic compounds using solid-phase extraction (SPE) and analysed by gas chromatography-mass spectrometry (GC/MS). The efficiencies of the SPE procedure was evaluated by recovery tests. A total of 38 compounds (carboxylic acids, fatty alcohols, phenolic compounds and sterols) were identified and quantified in the E. globulus bleached kraft pulp mill final effluent after secondary treatment. Recoveries from the extraction procedure were between 98.2% and 99.9%. The four fungi species showed an adequate capacity to remove organic compounds and colour. Tertiary treatment with R. oryzae was able to remove 99% of organic compounds and to reduce absorbance on 47% (270 nm) and 74% (465 nm). P. sajor caju, T. versicolor and P. chrysosporium were able to remove 97%, 92% and 99% of organic compounds, respectively, and reduce 18% (270 nm) to 77% (465 nm), 39% (270 nm) to 58% (465 nm) and 31% (270 nm) to 10% (465 nm) of absorbance

  5. Alkaline pulping of some eucalypts from Sudan.

    Science.gov (United States)

    Khristova, P; Kordsachia, O; Patt, R; Dafaalla, S

    2006-03-01

    Four eucalypts (Eucalyptus camaldulensis, Eucalyptus microtheca, Eucalyptus tereticornis and Eucalyptus citriodora) grown in Sudan were examined for their suitability for pulping and papermaking with different alkaline methods. Their physical, morphological and chemical characteristics are reported. The pulping trials with E. citriodora and E. tereticornis were carried out using the kraft-AQ, soda-AQ, modified AS/AQ (ASA), ASAM and kraft methods. For the other two species, only the ASAM and the kraft process were applied. ASAM pulping gave the best results in terms of yield, degree of delignification, mechanical and optical pulp properties. The best pulps, obtained in kraft and ASAM cooking of E. citriodora, were bleached to 88% ISO brightness in a totally chlorine free bleaching sequence (OQ1O/PQ2P). The bleached pulps, especially the ASAM pulp, showed good papermaking properties and would be suitable for manufacture of writing and printing grades of paper.

  6. Multivariate Analysis of Hemicelluloses in Bleached Kraft Pulp Using Infrared Spectroscopy.

    Science.gov (United States)

    Chen, Zhiwen; Hu, Thomas Q; Jang, Ho Fan; Grant, Edward

    2016-12-01

    The hemicellulose composition of a pulp significantly affects its chemical and physical properties and thus represents an important process control variable. However, complicated steps of sample preparation make standard methods for the carbohydrate analysis of pulp samples, such as high performance liquid chromatography (HPLC), expensive and time-consuming. In contrast, pulp analysis by attenuated total internal reflection Fourier transform infrared spectroscopy (ATR FT-IR) requires little sample preparation. Here we show that ATR FT-IR with discrete wavelet transform (DWT) and standard normal variate (SNV) spectral preprocessing offers a convenient means for the qualitative and quantitative analysis of hemicelluloses in bleached kraft pulp and alkaline treated kraft pulp. The pulp samples investigated include bleached softwood kraft pulps, bleached hardwood kraft pulps, and their mixtures, as obtained from Canadian industry mills or blended in a lab, and bleached kraft pulp samples treated with 0-6% NaOH solutions. In the principal component analysis (PCA) of these spectra, we find the potential both to differentiate all pulps on the basis of hemicellulose compositions and to distinguish bleached hardwood pulps by species. Partial least squares (PLS) multivariate analysis gives a 0.442 wt% root mean square errors of prediction (RMSEP) for the prediction of xylan content and 0.233 wt% RMSEP for the prediction of mannan content. These data all support the idea that ATR FT-IR has a great potential to rapidly and accurately predict the content of xylan and mannan for bleached kraft pulps (softwood, hardwood, and their mixtures) in industry. However, the prediction of xylan and mannan concentrations presented a difficulty for pulp samples with modified cellulose crystalline structure. © The Author(s) 2016.

  7. Corrosion testing in flash tanks of kraft pulp mills

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, S.J.; Stead, N.J.

    1999-11-01

    The corrosion observed in the first flash tanks in kraft pulp mills with modified cooking practices was characterized. Coupons of carbon steel (CS), several stainless steels (SS), and Ti were exposed at two mills. At one mill, identical sets of coupons were exposed in the No. 1 and No. 2 flash tank. At the other mill, three identical sets of coupons were placed in flash tank No. 1. The results of the exposures showed that both CS and Ti suffered high rates of general corrosion, while the SS suffered varying degrees of localized attack. The ranking of the corrosion resistance in the flash tank was the same that would be expected in a reducing acid environment. Attack by organic acids was concluded to be the most likely cause of corrosion of the flash tanks.

  8. Removal of COD and color loads in bleached kraft pulp effluents by bottom ashes from boilers.

    Science.gov (United States)

    Van Tran, A

    2008-07-01

    The effectiveness of the bottom ashes from biomass and coal-fired boilers in removing chemical oxygen demand (COD) and colorloads in effluents of a kraft pulp bleachery plant is investigated. The effluents tested are those of the sulfuric acid treatment (A stage) of a hardwood kraft pulp, and of the first acidic (chlorine or chlorine dioxide) and second alkaline (extraction) stages in the chlorine and elemental chlorine-free (ECF) bleaching lines of hardwood and softwood kraft pulps. The coal-fired boiler's bottom ashes are unable to remove either COD or color load in the bleached kraft pulp effluents. However, the bottom ashes of the biomass boiler are effective in removing COD and color loads of the acidic and alkaline effluents irrespective of the bleaching process or wood species. In particular, these ashes increase the pH of all the effluents examined.

  9. Relationship between lignin structure and delignification degree in Pinus pinaster kraft pulps.

    Science.gov (United States)

    Baptista, C; Robert, D; Duarte, A P

    2008-05-01

    This study examines the structure of residual and dissolved lignins from Pinus pinaster pulps obtained at different degrees of delignification by laboratory conventional kraft pulping. The cooking H factor was varied from 85 to 8049. The residual and dissolved lignin samples were characterised by elemental analysis, residual carbohydrate content, permanganate oxidation and 13C NMR spectroscopy. The reflectance factor of the pulps was also determined in order to tentatively correlate the delignification degree and residual lignin structure with the pulp colour. The obtained results confirmed that the delignification degree increases the condensation of the lignin structure, which might have an influence upon the observed increased pulp colour. The lack of selectivity of kraft pulping process in the case of more delignified pulps was also shown.

  10. Polyoxometalate delignification of birch kraft pulp and effect on residual lignin

    Science.gov (United States)

    Biljana Bujanovic; Richard S. Reiner; Sally A. Ralph; Rajai H. Atalla

    2011-01-01

    To advance the understanding of delignification with polyoxometalates (POMs) that have been explored for use in bleaching of chemical pulps, the transformation of lignin during anaerobic treatment of birch kraft pulp with an equilibrated POM mixture composed of Na5(+2)[SiV1(-0.1)MoW10(+0.1)O

  11. Green liquor impregnation and Kraft pulping of South African Pinus Patula – “A practical approach to provide cost savings in a Kraft mill’s pulping operation”

    CSIR Research Space (South Africa)

    Johakimu, Jonas K

    2011-02-01

    Full Text Available The effect of green liquor pre-treatment (GLP) on Kraft pulping of Pinus Patula has been investigated. Wood chips were pre-treated with green liquor, and subsequently subjected to Kraft pulping to achieve a target Kappa number of 65-70. The results...

  12. A multi-criteria decision analysis of management alternatives for anaerobically digested kraft pulp mill sludge.

    Directory of Open Access Journals (Sweden)

    Martijn Eikelboom

    Full Text Available The Multi-Criteria Decision Analysis (MCDA procedure was used to compare waste management options for kraft pulp mill sludge following its anaerobic digestion. Anaerobic digestion of sludge is advantageous because it produces biogas that may be used to generate electricity, heat and biofuels. However, adequate management of the digested sludge is essential. Landfill disposal is a non-sustainable waste management alternative. Kraft pulp mill digested sludge applied to land may pose risks to the environment and public health if the sludge has not been properly treated. This study is aimed to compare several recycling alternatives for anaerobically digested sludge from kraft pulp mills: land application, landfill disposal, composting, incineration, pyrolysis/gasification, and biofuel production by algae. The MCDA procedure considered nine criteria into three domains to compare digested sludge recycling alternatives in a kraft pulp mill: environmental (CO2 emission, exposure to pathogens, risk of pollution, material and energy recovery, economic (overall costs, value of products and technical (maintenance and operation, feasibility of implementation. The most suitable management options for digested sludge from kraft pulp mills were found to be composting and incineration (when the latter was coupled with recycling ash to the cement industry. Landfill disposal was the worst option, presenting low performance in feasibility of implementation, risk of pollution, material and energy recovery.

  13. A multi-criteria decision analysis of management alternatives for anaerobically digested kraft pulp mill sludge

    Science.gov (United States)

    Eikelboom, Martijn; Lopes, Alice do Carmo Precci; Silva, Claudio Mudadu; Rodrigues, Fábio de Ávila; Zanuncio, José Cola

    2018-01-01

    The Multi-Criteria Decision Analysis (MCDA) procedure was used to compare waste management options for kraft pulp mill sludge following its anaerobic digestion. Anaerobic digestion of sludge is advantageous because it produces biogas that may be used to generate electricity, heat and biofuels. However, adequate management of the digested sludge is essential. Landfill disposal is a non-sustainable waste management alternative. Kraft pulp mill digested sludge applied to land may pose risks to the environment and public health if the sludge has not been properly treated. This study is aimed to compare several recycling alternatives for anaerobically digested sludge from kraft pulp mills: land application, landfill disposal, composting, incineration, pyrolysis/gasification, and biofuel production by algae. The MCDA procedure considered nine criteria into three domains to compare digested sludge recycling alternatives in a kraft pulp mill: environmental (CO2 emission, exposure to pathogens, risk of pollution, material and energy recovery), economic (overall costs, value of products) and technical (maintenance and operation, feasibility of implementation). The most suitable management options for digested sludge from kraft pulp mills were found to be composting and incineration (when the latter was coupled with recycling ash to the cement industry). Landfill disposal was the worst option, presenting low performance in feasibility of implementation, risk of pollution, material and energy recovery. PMID:29298296

  14. Development of hemicelluloses biorefineries for integration into kraft pulp mills

    Science.gov (United States)

    Ajao, Olumoye Abiodun

    The development and wide spread acceptance of production facilities for biofuels, biochemicals and biomaterials is an important condition for reducing reliance on limited fossil resources and transitioning towards a global biobased economy. Pulp and paper mills in North America are confronted with high energy prices, high production costs and intense competition from emerging economies and low demand for traditional products. Integrated forest biorefineries (IFBR) have been proposed as a mean to diversify their product streams, increase their revenue and become more sustainable. This is feasible because they have access to forest biomass, an established feedstock supply chain and wood processing experience. In addition, the integration of a biorefinery process that can share existing infrastructure and utilities on the site of pulp mill would significantly lower investment cost and associated risks. Kraft pulping mills are promising receptor processes for a biorefinery because they either possess a prehydrolysis step for extracting hemicelluloses sugars prior to wood pulping or it can be added by retrofit. The extracted hemicelluloses could be subsequently transformed into a wide range of value added products for the receptor mill. To successfully implement hemicelluloses biorefinery, novel processes that are technically and economically feasible are required. It is necessary to identify products that would be profitable, develop processes that are energy efficient and the receptor mill should be able to supply the energy, chemicals and material demands of the biorefinery unit. The objective of this thesis is to develop energy efficient and economically viable hemicelluloses biorefineries for integration into a Kraft pulping process. A dissolving pulp mill was the reference case study. The transformation of hemicellulosic sugars via a chemical and biochemical conversion pathway, with furfural and ethanol as representative products for each pathway was studied. In

  15. 40 CFR 63.443 - Standards for the pulping system at kraft, soda, and semi-chemical processes.

    Science.gov (United States)

    2010-07-01

    ... Paper Industry § 63.443 Standards for the pulping system at kraft, soda, and semi-chemical processes. (a... operator of each pulping system using a semi-chemical or soda process subject to the requirements of this... kraft, soda, and semi-chemical processes. 63.443 Section 63.443 Protection of Environment ENVIRONMENTAL...

  16. Yield Improvement and Energy Savings Uing Phosphonates as Additives in Kraft pulping

    Energy Technology Data Exchange (ETDEWEB)

    Ulrike W. Tschirner; Timothy Smith

    2007-03-31

    Project Objective: Develop a commercially viable modification to the Kraft process resulting in energy savings, increased yield and improved bleachability. Evaluate the feasibility of this technology across a spectrum of wood species used in North America. Develop detailed fundamental understanding of the mechanism by which phosphonates improve KAPPA number and yield. Evaluate the North American market potential for the use of phosphonates in the Kraft pulping process. Examine determinants of customer perceived value and explore organizational and operational factors influencing attitudes and behaviors. Provide an economic feasibility assessment for the supply chain, both suppliers (chemical supply companies) and buyers (Kraft mills). Provide background to most effectively transfer this new technology to commercial mills.

  17. Papermaking Properties of Carpinus betulus with kraft, Soda and Soda-Urea Pulping Processes

    Directory of Open Access Journals (Sweden)

    Rasoul Darstan

    2013-06-01

    Full Text Available This research was carried out in order to comparatively investigate the hornbeam kraft, soda and soda-urea papermaking properties. The selected treatment in kraft process had an average yield of 44.43% and kappa number of 23.75. In soda process the selected treatment had an average yield of 38.75% and kappa number of 19.28. In soda-urea process, the selected treatments had an average yield of 39.85, 40.1, 40.5, 39.8 and 40.61 and kappa number of 21.21, 22.33, 22.66, 25.28 and 26.85. After refining the selected pulp to reach the freeness of 400±25 ml CSF, 60 g/m2 handsheets were made and physical, mechanical and optical properties were measured. Results showed that kraft pulps had higher yield and better refinability than soda and soda-urea pulps. Papers made from kraft process had higher strength properties than those made of soda and soda-urea process. With addition of urea, yield and kappa number of pulps increased. The highest improvement in tensile index, breaking length and tear index was achieved with addition of 3% urea and the highest improvement in burst index was achieved with adding 4% urea. Results of brightness measurements showed that papers from kraft and soda processes had the lowest and highest brightness degree respectively. With the addition of urea, brightness of papers decreased.

  18. PROCESS FOR THE PRODUCTION OF DISSOLVING PULP FROM TREMA ORIENTALIS (NALITA) BY PREHYDROLYSIS KRAFT AND SODA-ETHYLENEDIAMINE (EDA) PROCESS

    OpenAIRE

    M. A. Quaiyyum; A. Noori; Labooni Ahsan; M. Sarwar Jahan

    2008-01-01

    This paper presents a preliminary study for the production of dissolving pulp from Trema orientalis (Nalita). Water prehydrolysis kraft and soda-ethylenediamine (EDA) pulping for the production of dissolving pulp from T. orientalis was investigated. Prehydrolysis at 150 and 170 oC did not produce pulp with high α-cellulose content when using the kraft process. But addition of 0.25 % H2SO4 in prehydrolysis liquor increased the purity of the pulp with the sacrifice of pulp yield and viscosity. ...

  19. Eucalyptus Forest Information System for the Portuguese pulp and paper industry

    Science.gov (United States)

    Luis Fonseca; Rita Crespo; Henk Feith; Jose Luis Carvalho; Antonio Macedo; Joao Pedro Pina

    2000-01-01

    To support the management of the Portuguese eucalyptus forest, the Association of Portuguese Pulp and Paper Industries (CELPA) decided to develop a Eucalyptus Forest Information System (EFIS). The specific goals of the EFIS are: characterization and development of the eucalyptus forest over time; planning of successive national eucalyptus forest inventories; estimation...

  20. Alternative Technologies for Biofuels Production in Kraft Pulp Mills—Potential and Prospects

    Directory of Open Access Journals (Sweden)

    Esa Vakkilainen

    2012-07-01

    Full Text Available The current global conditions provide the pulp mill new opportunities beyond the traditional production of cellulose. Due to stricter environmental regulations, volatility of oil price, energy policies and also the global competitiveness, the challenges for the pulp industry are many. They range from replacing fossil fuels with renewable energy sources to the export of biofuels, chemicals and biomaterials through the implementation of biorefineries. In spite of the enhanced maturity of various bio and thermo-chemical conversion processes, the economic viability becomes an impediment when considering the effective implementation on an industrial scale. In the case of kraft pulp mills, favorable conditions for biofuels production can be created due to the availability of wood residues and generation of black liquor. The objective of this article is to give an overview of the technologies related to the production of alternative biofuels in the kraft pulp mills and discuss their potential and prospects in the present and future scenario.

  1. Kraft Pulp Bleaching and Delignification by Dikaryons and Monokaryons of Trametes versicolor

    Science.gov (United States)

    Addleman, Katherine; Archibald, Frederick

    1993-01-01

    The ability of 10 dikaryotic and 20 monokaryotic strains of Trametes (Coriolus) versicolor to bleach and delignify hardwood and softwood kraft pulps was assessed. A dikaryon (52P) and two of its mating-compatible monokaryons (52J and 52D) derived via protoplasting were compared. All three regularly bleached hardwood kraft pulp more than 20 brightness points (International Standards Organization) in 5 days and softwood kraft pulp the same amount in 12 days. Delignification (kappa number reduction) by the dikaryon and the monokaryons was similar, but the growth of the monokaryons was slower. Insoluble dark pigments were commonly found in the mycelium, medium, and pulp of the dikaryon only. Laccase and manganese peroxidase (MnP) but not lignin peroxidase activities were secreted during bleaching by all three strains. Their laccase and MnP isozyme patterns were compared on native gels. No segregation of isozyme bands between the monokaryons was found. Hardwood kraft pulp appeared to adsorb several laccase isozyme bands. One MnP isozyme (pI, 3.2) was secreted in the presence of pulp by all three strains, but a second (pI, 4.9) was produced only by 52P. A lower level of soluble MnP activity in one monokaryon (52D) was associated with reduced bleaching ability and a lower level of methanol production. Since monokaryon 52J bleached pulp better than its parent dikaryon 52P, especially per unit of biomass, this genetically simpler monokaryon will be the preferred subject for further genetic manipulation and improvement of fungal pulp biological bleaching. Images PMID:16348851

  2. Biofilms from micro/nanocellulose of NaBH4-modified kraft pulp

    Indian Academy of Sciences (India)

    Industrial applications of microfibrillated cellulose (MFC) and nanofibrillated cellulose (NFC) have been inuse for some time; however, there is a need to improve the production steps and at the same time to obtain better qualityproducts. NFC and MFC were generated from NaBH 4 -modified kraft pulp, produced from a red ...

  3. Influence of storage temperature of eucalypt chips on the quality of wood and of kraft pulp

    Energy Technology Data Exchange (ETDEWEB)

    Zvinakevicius, C.; Foelkel, C.E.B.; Andrade, J.R.

    1978-01-01

    Storage of eucalypt chips at high temperature (up to 70 degrees C) led to a reduction in yield and strength (particularly folding strength) of kraft pulp made from the chips. Storage also increased the content of 1% NaOH extractives in the chips and lowered their pH.

  4. Alkaliphilic endoxylanase from lignocellulolytic microbial consortium metagenome for biobleaching of eucalyptus pulp.

    Science.gov (United States)

    Weerachavangkul, Chawannapak; Laothanachareon, Thanaporn; Boonyapakron, Katewadee; Wongwilaiwalin, Sarunyou; Nimchua, Thidarat; Eurwilaichitr, Lily; Pootanakit, Kusol; Igarashi, Yasuo; Champreda, Verawat

    2012-12-01

    Enzymatic pre-bleaching by modification of pulp fibers with xylanases is an attractive approach to reduce the consumption of toxic bleaching chemicals in the paper industry. In this study, an alkaliphilic endoxylanase gene was isolated from metagenomic DNA of a structurally stable thermophilic lignocellulose-degrading microbial consortium using amplification with conserved glycosyl hydrolase family 10 primers and subsequent genome walking. The full-length xylanase showed 78% sequence identity to an endo-beta-1,4-xylanase of Clostridium phytofermentans and was expressed in a mature form with an N-terminal His6 tag fusion in Escherichia coli. The recombinant xylanase Xyn3F was thermotolerant and alkaliphilic, working optimally at 65-70 degrees C with an optimal pH at 9- 10 and retaining >80% activity at pH 9, 60 degrees C for 1 h. Xyn3F showed a Vmax of 2,327 IU/mg and Km of 3.5 mg/ml on birchwood xylan. Pre-bleaching of industrial eucalyptus pulp with no prior pH adjustment (pH 9) using Xyn3F at 50 IU/g dried pulp led to 4.5-5.1% increase in final pulp brightness and 90.4-102.4% increase in whiteness after a single-step hypochlorite bleaching over the untreated pulp, which allowed at least 20% decrease in hypochlorite consumption to achieve the same final bleaching indices. The alkaliphilic xylanase is promising for application in an environmentally friendly bleaching step of kraft and soda pulps with no requirement for pH adjustment, leading to improved economic feasibility of the process.

  5. Biological treatment of the effluent from a bleached kraft pulp mill using basidiomycete and zygomycete fungi.

    Science.gov (United States)

    Freitas, A C; Ferreira, F; Costa, A M; Pereira, R; Antunes, S C; Gonçalves, F; Rocha-Santos, T A P; Diniz, M S; Castro, L; Peres, I; Duarte, A C

    2009-05-01

    Three white-rot fungi (Pleurotus sajor caju, Trametes versicolor and Phanerochaete chrysosporium) and one soft-rot fungi (Rhizopus oryzae) species confirmed their potential for future applications in the biological treatment of effluents derived from the secondary treatment of a bleached kraft pulp mill processing Eucalyptus globulus. Among the four species P. sajor caju and R. oryzae were the most effective in the biodegradation of organic compounds present in the effluent, being responsible for the reduction of relative absorbance (25-46% at 250 nm and 72-74% at 465 nm) and of chemical oxygen demand levels (74 to 81%) after 10 days of incubation. Laccase (Lac), lignin (Lip) and manganese peroxidases (MnP) expression varied among fungal species, where Lac and LiP activities were correlated with the degradation of organic compounds in the effluent treated with P. sajor caju. The first two axes of a principal component analysis explained 88.9% of the total variation among sub-samples treated with the four fungus species, after different incubation periods. All the variables measured contributed positively to the first component except for the MnP enzyme activity which was the only variable contributing negatively to the first component. Absorbances at 465 nm, LiP and Lac enzyme activities were the variables with more weight on the second component. P. sajor caju revealed to be the only species able to perform the biological treatment without promoting an increment in the toxicity of the effluent to the Vibrio fischeri, as it was assessed by the Microtox assay. The opposite was recorded for the treatments with the other three species of fungus. EC(50-5 min) values ranging between 28 and 57% (effluent concentrations) were recorded even after 10 to 13 days of treatment with P. chrysosporium, R. oryzae or with T. versicolor.

  6. Qualidade da celulose kraft-antraquinona de Eucalyptus dunnii plantado em cinco espaçamentos em relação ao Eucalyptus grandis e Eucalyptus saligna.

    Directory of Open Access Journals (Sweden)

    Giovanni Willer Ferreira

    2009-09-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 Este trabalho analisou o efeito de cinco espaçamentos de Eucalyptus dunnii (3 m x 1 m; 3 m x 1,5 m; 3 m x 2 m; 3 m x 3 m; 3 m x 4 m, para produção de celulose kraft-antraquinona, comparados com Eucalyptus grandis e Eucalyptus saligna (ambos no espaçamento 3 m x 2 m. Avaliaram-se a densidade básica e composição química da madeira original, analisando-se extrativos em diclorometano, pentosanas, lignina, solubilidade em NaOH8% e cinzas. Os cavacos foram submetidos a cozimento kraft-antraquinona com álcali ativo variando de 18,5 a 21% para obter um número kappa 17± 1,5; sulfidez a 8%, antraquinona base madeira 0,05%, relação licor/madeira 4:1, tempo até temperatura máxima 60 minutos, tempo à temperatura máxima 45 minutos. A celulose marrom resultante do cozimento kraft-antraquinona foi caracterizada e analisada em seus aspectos físico-químicos (rendimentos, rejeitos, número kappa, viscosidade intrínseca, alvura e solubilidade em NaOH5%. Uma parte desta sofreu refinação em moinho Jökro ao nível de 35°SR e, juntamente com a polpa não-refinada, foram submetidas a testes físico-mecânicos e óticos (resistência à tração, alongamento, estouro, rasgo, volume específico, alvura, resistência ao ar Gurley e ascensão capilar Klemm. O maior consumo de álcali ativo (20,5% ocorreu em espaçamento 3 m x 4 m, proporcionando maior degradação da polpa. Todos os espaçamentos caracterizados apresentaram viabilidade para a produção de celulose kraft-antraquinona, podendo proporcionar redução nos custos de produção de celulose, devido aos menores consumos apresentados de álcali ativo e madeira quando comparados com Eucalyptus grandis e Eucalyptus saligna. Os valores de extrativos e cinzas mostraram-se elevados para Eucalyptus dunnii, potencializando possíveis impactos em termos de incrustações e fechamento de circuito no processo fabril. Diante dos resultados

  7. Optical Approach To The Measurement Of Delignification In Kraft Pulping: Part B: Using Infrared Spectroscopy.

    Science.gov (United States)

    Adam, E.; Sugden, N.

    1986-10-01

    A study of the infrared (IR) absorption characteristics of dried kraft pulp sheets was made. This was done in order to assess the potential of using this approach as the basis for determining residual lignin, or Kappa number, in pulp after cooking. Strong positive linear correlations were obtained between Kappa number and IR absorbance at 1509 cm-for pulps made from different wood species, produced in different mills and having a Kappa number range of 13-37. For pulps from some mills, made from the same wood furnish and having a small Kappa number range, the degree of correlation was seriously reduced. The method requires the use of moisture-free pulp specimens in the measurement of absorbance. It is suggested that it would be more suitable as the basis for a laboratory instrument than for an on-line, process Kappa number sensor.

  8. Kinetics of liquid-solid reactions in naphthenic acid conversion and Kraft pulping

    Science.gov (United States)

    Yang, Ling

    Two liquid-solid reactions, in which the morphology of the solid changes as the reactions proceeds, were examined. One is the NA conversion in oil by decarboxylation on metal oxides and carbonates, and the other is the Kraft pulping in which lignin removal by delignification reaction. In the study of the NA conversion, CaO was chosen as the catalyst for the kinetic study from the tested catalysts based on NA conversion. Two reaction mixtures, carrier oil plus commercial naphthenic acids and heavy vacuum gas oil (HVGO) from Athabasca bitumen, were applied in the kinetic study. The influence of TAN, temperature, and catalyst loading on the NA conversion and decarboxylation were studied systematically. The results showed that the removal rate of TAN and the decarboxylation of NA were both independent of the concentration of NA over the range studied, and significantly dependent on reaction temperature. The data from analyzing the spent catalyst demonstrated that calcium naphthenate was an intermediate of the decarboxylation reaction of NA, and the decomposition of calcium naphthenate was a rate-determining step. In the study on the delignification of the Kraft pulping, a new mechanism was proposed for the heterogeneous delignification reaction during the Kraft pulping process. In particular, the chemical reaction mechanism took into account the heterogeneous nature of Kraft pulping. Lignin reacted in parallel with sodium hydroxide and sodium sulfide. The mechanism consists of three key kinetic steps: (1) adsorption of hydroxide and hydrosulfide ions on lignin; (2) surface reaction on the solid surface to produce degraded lignin products; and (3) desorption of degradation products from the solid surface. The most important step for the delignification process is the surface reaction, rather than the reactions occurring in the liquid phase. A kinetic model has, thus, been developed based on the proposed mechanism. The derived kinetic model showed that the mechanism

  9. Pulp and paper production from Spruce wood with kraft and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-15

    Mar 15, 2010 ... Science and Technology Series, Gummerus Printing, Jyvaskyla,. Finland. Hafızoglu H, Deniz I (2007). Wood Chemistry, KTU Faculty of Forestry. Progress, Trabzon. Johansson A, Altonen O, Ylinen P (1987). Organasolv Pulping Methods and Pulping Properties, Biomass, 13(15): 45-52. Kırcı H (2006).

  10. Yield-increasing additives in kraft pulping: Effect on carbohydrate retention, composition and handsheet properties

    Energy Technology Data Exchange (ETDEWEB)

    Vaaler, David Andre Grimsoeen

    2008-07-01

    In this thesis, increased hemicellulose retention during kraft pulping has been studied. The work has been divided into three parts: i) Development of an accessible and reliable method for determination of carbohydrate composition of kraft pulps ii) Investigation of the composition and molecular mass distributions of the carbohydrates in kraft pulps with increased hemicellulose content iii) Investigation of the effect of increased hemicellulose content on the sheet properties of kraft pulps with increased hemicellulose content. A method for carbohydrate determination was developed. In this method, enzymes are used to hydrolyse the pulp into monosaccharides. A relatively mild acid hydrolysis is performed prior to detection on an HPLC with an RI-detector. The pulp is not derivatized and no pre-treatment (mechanical or chemical) is needed to determine the carbohydrate composition using the method developed here. Peak deconvolution software is used to improve the accuracy. Polysulphide and H2S primarily increase the glucomannan yield, which can be boosted by up to 7 % on o.d. wood. However, the cellulose yield is more affected by the cooking time and the maximum yield increase of cellulose is approximately 2 % on o.d. wood compared to an ordinary kraft pulp. The cooking time is influenced by sulphide ion concentration, AQ addition and the final Kappa number. The xylan yield is remarkably stable, however the alkali profile during the cook may influence the xylan yield. Surface xylan content of the fibres depends on residual alkali concentration in the black liquor. The molecular mass distributions of cellulose and hemicellulose were determined for pulps with increased hemicellulose content using size exclusion chromatography. Deconvolution by peak separation software is used to gain information about the degree of polymerization for cellulose and hemicellulose. The average DP of glucomannan in the kraft fibre was found to be 350 +- 30 and the average DP of xylan in the

  11. Uso de antraquinona en cocción kraft de Eucalyptus globulus y Eucalyptus nitens

    OpenAIRE

    Moreira, Jorge Felipe Quintana

    2011-01-01

    En la presente disertación se verificó de manera experimental el efecto de la adición de Antraquinona al proceso de cocción batch convencional para una mezcla industrial de Eucalyptus globulus E. nitens.; en lo que respecta a su capacidad de aumentar la velocidad de la reacción de deslignificación y proporcionar estabilidad a las hemicelulosas y celulosas de la fibra. Lo anterior se logró con experiencias de laboratorio fijando las condiciones de cocción de acuerdo a la operación de los dig...

  12. Reutilization of effluents from laccase-mediator treatments of kraft pulp for biobleaching.

    Science.gov (United States)

    Moldes, D; Vidal, T

    2011-02-01

    Several effluents from laccase-mediator treatments of kraft pulp were recovered and subsequently reused with fresh pulp in order to simulate recirculation of effluents during biobleaching. The effluents were used as a new bleaching stage without any modification except enzyme addition. Pulp treated with effluents were afterwards chemically bleached by using the simple sequence LQPo, where L represents the treatment with effluent and laccase addition, Q is a chelating stage and Po is an alkaline peroxide stage. This system showed a promising potential on delignification, with kappa number ranging from 5.5 to 6.6 after LQPo sequence, depending on the type of effluent employed in L stage. Improvements on pulp brightness were also reported compared with control experiment. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Kraft lignin depolymerisation by based catalysed degradation (BCD) - The effect of process parameters on conversion degree and structural features of BCD fractions

    OpenAIRE

    Schmiedl, Schmiedl; Böringer, Sarah; Schweppe, Rainer; Liitiä, Tiina; Rovio, Stella; Tamminen, Tarja; Rencoret, Jorge; Gutiérrez Suárez, Ana; Río Andrade, José Carlos del; Río Andrade, José Carlos del

    2014-01-01

    The objective of the study is the generation of oxy-aromatic compounds (monomer, oligomer) from Eucalyptus- Kraft-lignin via multi-stage processes. These processes (1st base catalysed degradation & 2nd separation of the organic phase from reactor water) have to be feasible in bio refineries & in new Pulp-mill bio refineries as a new technology module. The Eucalyptus-Kraft-lignin (Suzano Pulp & Paper) was used for catalyzed conversion into oxy aromatics. Subsequently, the effect of process par...

  14. Can Acceptable Pulp be Obtained from Eucalyptus globulus Wood Chips after Hemicellulose Extraction?

    OpenAIRE

    Francisco López; M. Trinidad García; Vicente Mena; J. Mauricio Loaiza; Minerva A. M. Zamudio; Juan C. García

    2014-01-01

    This study investigates the operating conditions used in the soda-anthraquinone pulping of Eucalyptus globulus wood after autohydrolysis pretreatment on the yield, kappa number, and brightness of the resulting unbleached pulp. Moreover, strength-related properties of the resulting handsheets was examined to identify the best pulping conditions and compare the outcome with that of a conventional soda-anthraquinone pulping process. The paper strength properties of the pulp were similar to or be...

  15. Fate of Residual Lignin during Delignification of Kraft Pulp by Trametes versicolor

    Science.gov (United States)

    Reid, Ian D.

    1998-01-01

    The fungus Trametes versicolor can delignify and brighten kraft pulps. To better understand the mechanism of this biological bleaching and the by-products formed, I traced the transformation of pulp lignin during treatment with the fungus. Hardwood and softwood kraft pulps containing 14C-labelled residual lignin were prepared by laboratory pulping of lignin-labelled aspen and spruce wood and then incubated with T. versicolor. After initially polymerizing the lignin, the fungus depolymerized it to alkali-extractable forms and then to soluble forms. Most of the labelled carbon accumulated in the water-soluble pool. The extractable and soluble products were oligomeric; single-ring aromatic products were not detected. The mineralization of the lignin carbon to CO2 varied between experiments, up to 22% in the most vigorous cultures. The activities of the known enzymes laccase and manganese peroxidase did not account for all of the lignin degradation that took place in the T. versicolor cultures. This fungus may produce additional enzymes that could be useful in enzyme bleaching systems. PMID:9603823

  16. Soda-anthraquinone, kraft and organosolv pulping of holm oak trimmings.

    Science.gov (United States)

    Alaejos, J; López, F; Eugenio, M E; Tapias, R

    2006-11-01

    The operating conditions for an organosolv (ethyleneglycol) and two alkaline (soda-anthraquinone and kraft) processes for obtaining cellulose pulp and paper from holm oak (Quercus ilex) wood trimmings were optimized. A range of variation for each process variable (viz. temperature, cooking time and soda or ethyleneglycol concentration) was established and a central composite experimental design involving three independent variables at three different variation levels was applied. The results obtained with the three cooking processes used were compared and those provided by the kraft process were found to be the best. Thus, the tensile index values it provided (5.9-16.3 N m/g) were 23.7% and 41.5% better than those obtained with the soda-AQ and ethyleneglycol processes, respectively. Also, the kraft process provided the best burst index, brightness and kappa number values. Based on the optimum working ranges, the temperature and cooking time were the variables resulting in the most and least marked changes, respectively, in pulp properties.

  17. Acetosolv pulping of Eucalyptus globulus wood. Pt. 1. The effect of operational variables on pulp yield, pulp lignin content and pulp potential glucose content

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, G. [Dept. of Chemical Engineering, Univ. of Santiago de Compostela (Spain); Antorrena, G. [Dept. of Chemical Engineering, Univ. of Santiago de Compostela (Spain); Gonzalez, J. [Dept. of Chemical Engineering, Univ. of Santiago de Compostela (Spain)

    1995-07-01

    The HCl-catalysed delignification of Eucalyptus globulus wood by aqueous acetic acid was optimized in accordance with an incomplete 3x3x3 factorial design with HCl concentration (0-0.05%), temperature (120-160 C) and reaction time (1-4 h) as independent variables and pulp yield, pulp lignin content and pulp potential glucose content as dependent variables. Empirical equations derived from the results satisfactorily predict the influence of the independent variables on these characteristics of the delignification process and the delignified pulps. (orig.)

  18. Cynara cardunculus L. alkaline pulps: alternatives fibres for paper and paperboard production.

    Science.gov (United States)

    Abrantes, S; Amaral, M E; Costa, A P; Duarte, A P

    2007-11-01

    The pulping of Cynara cardunculus L. (cardoon) was performed under conditions for kraft, kraft-AQ and soda-AQ processes. The best results in terms of delignification degree, expressed as kappa number, pulp viscosity and screened yield, were obtained for the kraft-AQ process with 0.20% of anthraquinone (AQ). The papermaking potential of the selected pulp was studied attending to biometric fibre characterisation, refining aptitude, optical and strength properties. All properties were compared against a Eucalyptus globulus pulp at different refining degrees. The cardoon pulp was also evaluated concerning its potential to board manufacture, alone and in mixtures with pine pulp, giving rise to promising results for liner manufacture.

  19. Characterization of solid wastes from kraft pulp industry for ceramic materials development purposes

    International Nuclear Information System (INIS)

    Rodrigues, L.R.; Francisco, M.A.C.O.; Sagrillo, V.P.D.; Louzada, D.M.; Entringer, J.M.S.

    2016-01-01

    The Kraft pulp industry generates a large amount of solid wastes. Due this large quantity, the target of this study is characterize inorganic solid wastes, dregs, grits and lime mud, from the step of reagents recovery of Kraft process, aiming evaluate the potentiality of their use as alternative raw material on development of ceramic materials. Initially, the wastes were dried and ground, then they were subjected to the following characterization techniques: pH analysis, particle size analysis, X ray fluorescence, X ray diffraction, differential thermal analysis and thermogravimetric analysis and scanning electron microscopy. According to the results, it may be concluded that these wastes could be used as raw material in production of red ceramic and luting materials. (author)

  20. Effect of depth beating on the fiber properties and enzymatic saccharification efficiency of softwood kraft pulp.

    Science.gov (United States)

    Gao, Wenhua; Xiang, Zhouyang; Chen, Kefu; Yang, Rendang; Yang, Fei

    2015-01-01

    Commercial bleached softwood kraft pulp was mechanically fibrillated by a PFI-mill with beating revolution from 5000 to 30,000 r. The extent of fibrillating on the pulp was evaluated by beating degree, fiber morphological properties (fiber length, width, coarseness and curls index), water retention value (WRV) and physical properties of paper made from the pulp. Depth beating process significantly affected the pulp fibrillations as showed by the decreased fiber length and width as well as the SEM analysis, but the effects were limited after beating revolution of 15,000. Depth beating process also improved the total internal pore and inter-fibril surface areas as shown by the increased WRV values. Substrate enzymatic digestibility (SED) of beaten pulp at 5000 revolutions could reach 95% at cellulase loading of 15 FPU/g of glucan. After the enzymatic hydrolysis, the size of the pulp residues was reduced to micro-scale, and a relative uniform size distribution of the residues appeared at 10,000 r beating revolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Estimation of Acacia melanoxylon unbleached Kraft pulp brightness by NIR spectroscopy

    Directory of Open Access Journals (Sweden)

    António J. A. Santos

    2015-08-01

    Full Text Available Aim of the study: The ability of NIR spectroscopy for predicting the ISO brightness was studied on unbleached Kraft pulps of Acacia melanoxylon R. Br. Area of study: Sites covering littoral north, mid interior north and centre interior of Portugal. Materials and methods: The samples were Kraft pulped in standard identical conditions targeted to a kappa number of 15. A Near Infrared (NIR partial least squares regression (PLSR model was developed for the ISO brightness prediction using 75 pulp samples with a variation range of 18.9 to 47.9 %. Main results: Very good correlations between NIR spectra and ISO brightness were obtained. Ten methods were used for PLS analysis (cross validation with 48 samples, and a test set validation was made with 27 samples. The 1stDer pre-processed spectra coupling two wavenumber ranges from 9404 to 7498 cm-1 and 4605 to 4243 cm-1 allowed the best model with a root mean square error of ISO brightness prediction of 0.5 % (RMSEP, a r2 of 99.5 % with a RPD of 14.7. Research highlights: According to AACC Method 39-00, the present model is sufficiently accurate to be used for process control (RPD ≥ 8

  2. Recycling of water in bleached kraft pulp mills by using electrodialysis.

    Energy Technology Data Exchange (ETDEWEB)

    Fracaro, A. T.; Henry, M. P.; Pfromm, P.; Tsai, S.-P.

    1999-01-15

    Conservation of water in bleached kraft pulp mills by recycling the bleach plant effluent directly without treatment will cause accumulation of inorganic ''non-process elements'' (NPEs) and serious operational problems. In this work, an electrodialysis process is being developed for recycling the acidic bleach plant effluent of bleached kraft pulp mills. In this process, electrodialysis functions as a selective kidney to remove inorganic NPEs from bleach plant effluents, before they reach the recovery cycle. Acidic bleach plant effluents from several mills using bleaching sequences based on chlorine dioxide were characterized. The total dissolved solids were mostly inorganic NPEs. Sodium was the predominant cation and chloride was present at significant levels in all these effluents. In laboratory electrodialysis experiments, selective removal of chloride and potentially harmful cations, such as potassium, calcium, and magnesium, were removed efficiently. Rejection of organic compounds was up to 98%. Electrodialysis was shown to be resistant to membrane fouling and scaling, in a 100-hour laboratory experiment. Based on a model mill with 1,000 ton/day pulp production, the economic analysis suggests that the energy cost of electrodialysis is less than $200/day, and the capital cost of the stack is about $500,000.

  3. Bleached kraft pulp production from Pinus tecunumanii (Eguiluz e Perry Produção de polpa kraft branqueada de Pinus tecunumanii (Eguiluz e Perry

    Directory of Open Access Journals (Sweden)

    Leonel F. Torres

    2005-06-01

    Full Text Available The use of 12-year-old Pinus tecunumanii (Eguiluz e Perry grown in Colombia was evaluated for bleached kraft pulp production. Kraft pulps of kappa number 30 ± 1 were produced, and oxygen delignified and bleached to 90% ISO with ECF processes. The bleached pulps produced under optimum conditions were evaluated with regard to their strength properties. Pinus tecunumanii wood required low effective alkali charge to reach the desired kappa number and the unbleached pulp showed high oxygen delignification efficiency and bleachability when a OD(EODED sequence was used. The bleached pulps presented good physical-mechanical properties, which are comparable to those obtained with more traditional pines such as Pinus taeda and Pinus radiata. The results demonstrate that this tropical pine species is a suitable raw material for bleached kraft pulp productionForam avaliadas amostras de Pinus tecunumanii de (Eguiluz e Perry com 12 anos de idade procedente da Colômbia, para produção de polpa de kraft branqueada. Produziram-se polpas kraft com número kappa 30±1, deslignificada com oxigênio e branqueada a 90% ISO por processo ECF. As polpas branqueadas foram produzidas em condições ótimas e avaliadas com relação às suas propriedades de resistência. A madeira de Pinus tecunumanii exigiu baixa carga de álcali efetivo para alcançar o número kappa desejado, e a polpa marrom mostrou eficiência na deslignificação com oxigênio e alta branqueabilidade quando submetida à seqüência OD(EODED. As polpas branqueadas apresentaram boas propriedades físico-mecânicas, em comparação com aquelas obtidas das espécies tradicionais de Pinus, como o Pinus taeda e o Pinus radiata. Os resultados indicaram que essa espécie de pinus tropical é uma matéria-prima satisfatória para produção de polpa de kraft branqueada.

  4. Cellulose kraft pulp reinforced polylactic acid (PLA composites: effect of fibre moisture content

    Directory of Open Access Journals (Sweden)

    Elias Retulainen

    2016-06-01

    Full Text Available PLA offers a competitive and CO2 neutral matrix to commonly used polyolefin polymer based composites. Moreover, the use of PLA reduces dependency on oil when producing composite materials. However, PLA has a tendency of hydrolytic degradation under melt processing conditions in the presence of moisture, which remains a challenge when processing PLA reinforced natural fibre composites. Natural fibres such as cellulose fibres are hygroscopic with 6–10 wt% moisture content at 50–70% relative humidity conditions. These fibres are sensitive to melt processing conditions and fibre breakage (cutting also occur during processing. The degradation of PLA, moisture absorption of natural fibres together with fibre cutting and uneven dispersion of fibres in polymer matrix, deteriorates the overall properties of the composite. In the given research paper, bleached softwood kraft pulp (BSKP reinforced PLA compounds were successfully melt processed using BSKP with relatively high moisture contents. The effect of moist BSKP on the molecular weight of PLA, fibre length and the mechanical properties of the composites were investigated. By using moist never-dried kraft pulp fibres for feeding, the fibre cutting was decreased during the melt compounding. Even though PLA degradation occurred during the melt processing, the final damage to the PLA was moderate and thus did not deteriorate the mechanical properties of the composites. However, comprehensive moisture removal is required during the compounding in order to achieve optimal overall performance of the PLA/BSKP composites. The economic benefit gained from using moist BSKP is that the expensive and time consuming drying process steps of the kraft pulp fibres prior to processing can be minimized.

  5. THE EFFECT OF WATER REDUCTION IN KRAFT PULP WASHING IN ECF BLEACHING

    Directory of Open Access Journals (Sweden)

    Tânia Cristina Frigieri

    Full Text Available ABSTRACT The main objective of this work was to study the technical viability of using the cellulose bleaching effluent, at several stages of the process, seeking fresh water reduction in pulp washing, and evaluating its effect on pulp quality. Eucalyptus spp. industrial cellulosic pulp with oxygen was used in this experiment. The same bleaching sequence D(E+PDP was performed ten times, under the same conditions (temperature, consistency and time. Counter current washing was used in the bleaching stages, and each sequence was carried out with different washing factors: 9, 6, 3, 0 m3 of distilled water/ton of pulp, trying to reach brightness of 92 ± 0,5% ISO. The ten sequences sought to achieve the stability of the effluent organic load, measured by the chemical oxygen demand (COD. Then, the COD results were compared to the brightness ones from the bleached pulp. The evaluated results from the ten sequences and four different washings showed an increasing in COD due to the organic load accumulation, resulting from the reuse of effluent from previous sequences. This COD increasing provided the lower brightness results during the cycles, besides the water reduction, evidencing the necessity of washing between bleaching stages. In this study, the obtained result for the pulp washing up to 3m3/t was tolerable and even recommended. On the other hand, the pulp without any washing (0m3/t, due to the lack of enough brightness, it is commercially unviable.

  6. ECONOMIC ROTATION OF Eucalyptus grandis PLANTATIONS FOR PULP PRODUCTION

    Directory of Open Access Journals (Sweden)

    Thais Cunha Ferreira

    2004-07-01

    Full Text Available The objectives of the research were: to determine the economic impact of several minimum diameter and length of logs in economic rotation age, economic feasibility of Eucalyptus grandis plantation for cellulose production; to determine the economic loss of cutting the stand before or after the optimal economic rotation age. A biometric model for making wood volume prognosis was developed using data of a trial of Eucalyptus grandis plantation envisaging pulp production. Eucalyptus grandis stands of 19 and 103 months old, in the spacing 3 x 2 and 3 x 3 m in site index of 30; 28; 26 and 24 m were used. Theprognosis started at the age zero, considering logs of 2.5; 2.8; 4.0 and 6.0 m of length for minimum diameter varying from 4 to 10 cm, in intervals of 2 cm. Net Present Worth (VPL was used the economic criterion, considering an infinite horizon and a cost relation including reestablishment, yearly maintenance, logging and wood transportation costs. The main conclusions were: increases in the minimum diameter and or in logs length increase the rotation age; harvesting the stands in ages different from the optimal one cause large economic loss mainly in the better sites; the economic loss is larger if the harvest is made before the optimal economic rotation than if it is make after; economic feasibility increases when the minimum diameter is smaller and when the length of the logs is shorter. Any way, before making any decision it is necessary to take into account possible technical restrictions and effect on harvest and transportation costs caused by changer in the length of logs and in the size of the minimum commercial diameter.

  7. Biobleaching of eucalypt kraft pulp with a two laccase-mediator stages sequence.

    Science.gov (United States)

    Moldes, D; Cadena, E M; Vidal, T

    2010-09-01

    A new biobleaching sequence, with two enzymatic stages based on the application of laccase-mediator systems, was tested (L(1)EL(2)QPo) in order to increase the effectiveness of enzyme delignification on eucalypt kraft pulp. Different synthetic -1-hydroxybenzotriazole (HBT) and violuric acid (VA) - and natural - syringaldehyde (SyAl) - mediators were used in the laccase stages and the biobleached pulp were compared in terms of chemical, optical and physico-mechanical properties. The pulp bleached with HBT or VA showed similar delignification (64.1% and 65.9% respectively) and optical properties (86.4% and 86.1% ISO brightness respectively) than an industrial TCF pulp (68.3% delignification and 84.8% ISO brightness). SyAl improved these properties in a lower extent (56.71% delignification and 80.52% ISO brightness). Regarding physico-mechanical properties of pulp, the biobleaching sequence had no a negative effect, even some slight improvements were observed in very specific cases. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. The role of organic matter lost in kraft pulping material balances .

    Science.gov (United States)

    Luonsi, A; Lento, S; Halttunen, S; Ala-Kaila, K

    2003-01-01

    Efficiency improvement in a pulp mill includes minimisation of environmental discharges simultaneously with the development of pulp quality and production economy. Material balances in production processes, including fate of sidestreams, are key in proceeding these matters. Different approaches of determining the material balances increase understanding of process behaviour. We have focused on measuring sidestream (carryovers, washing water, filtrate) dissolved organic matter (DOM) in fibreline unit process blocks of softwood ECF bleached kraft production. The DOM was analysed by traditional wastewater methods (volatile solids, organic carbon, chemical oxygen demand). The measured data was combined with primarily simulated water balances and routine operational mill data in a simulation model. From this balance, yield estimate included, lost organic matter through complete degradation (CD) and volatile organic compounds (VOC) can be calculated throughout the fibreline. The sensitivity of this considerable amount (23-35 kgDVS/adt in total) to various factors is discussed in this paper.

  9. The Comparison of Kraft Pulp Properties from Stem and Branchwood of Hornbeam

    Directory of Open Access Journals (Sweden)

    Ebrahim Pouryazdian

    2014-05-01

    Full Text Available The utilization of tree branches as potential resource of fibers, that can be supply raw materials for pulp and paper industries, additionally, increases the productivity of tree. This research was done in order to compare pulp and paper properties from branch wood and stem wood and feasibility utilization that in pulp and paper industries. Stem and branch wood samples of hornbeam with mean diameter about 15 cm were obtained from Shastkolateh educational forest (Gorgan.The measurement of fibers was done with using Franklin method and light microscopic and chemical compositions were determined according to TAPPI test methods. The Kraft pulps from stem and branch wood were prepared under constant condition include sulfudity 20%, Max temp 170˚C and Liquor to wood ratio 5/1 and variable condition include active alkali 14%, 16% and 18%, and cooking time of 90, 120 and 150 min. Ultimately mechanical properties of Handsheet were measured according TAPPI test method The statistical analysis of results indicated that independent effects of wood, active alkali, and time were significant on pulp yield and Kappa number. Comparing the pulp yield and Kappa number means were showing that yield of stem wood pulp is higher than branch wood and its kappa number is less. Analysis mechanical properties on stem and branch wood Hand sheets showed that mechanical properties of Hand sheet from stem wood are higher than branch wood. There is none meaningful difference between the most mechanical properties hand sheets of stem and branch wood, that produced under cooking condition include sulfudity 20%, active alkali 18% and cooking time 150 min. therefore this condition would suggest for simultaneous cooking branch and stem wood

  10. Growth of Pinus radiada in soil containing solid waste from the kraft pulp industry

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, M.; Vicuna, R.; Gonzalez, B.; Bronfman, M. [Pontificia Universidad Catolica de Chile, Facultad de Ciencias Biologicas, Santiago (Chile); Osses, M. [Celulosa Arauco y Constitucion, Arauco (Chile); Toro, J.; Balocchi, C.; Rodriguez, E. [Bioforest, S.A, Concepcion (Chile)

    2000-06-01

    The germination and growth of Pinus radials Don. plantlets in solid residues deriving from a Kraft pulp industry was evaluated. Plant conditions were monitored by histological studies of roots and shoot-tips, as well as by plant analyses of several essential and non essential elements. The solids employed consisted of ashes, fly-ashes, dregs, grits, primary sludge, brown stock screening rejects and various mixtures of them. Their addition, in a range of combinations to sandy/metamorphic or marine terrace/clay soils, resulted in effective and sustained growth under greenhouse conditions. Low proportions of wastes favored growth in most cases, indicating that they may act as fertilisers. In some experiments, especially in those where waste was added in proportions ranging from 50% to 60%, germination and/or development were slightly affected. Two-year old field experiments have confirmed that in spite of the high pH values, Na ion content or elevated water retention capacity exhibited by some of the solids tested, their use is beneficial for the growth of radiate pine. To date, we have not observed negative effects other than growth inhibition when some solids are present at concentrations above 60%. Our preliminary results suggest that an adequate use as fertiliser of solid waste from the Kraft pulp industry may constitute a profitable alternative in its management. (orig.)

  11. Production of thermo-alkali-stable laccase and xylanase by co-culturing of Bacillus sp. and B. halodurans for biobleaching of kraft pulp and deinking of waste paper.

    Science.gov (United States)

    Gupta, Vijaya; Garg, Shruti; Capalash, Neena; Gupta, Naveen; Sharma, Prince

    2015-05-01

    To reduce pollution and cost of treatment for fresh and recycled paper, co-production of xylanase and laccase was carried out in the same production medium using two compatible species of Bacillus. These co-produced enzymes were used for deinking of old newsprint (ONP) and biobleaching of eucalyptus Kraft pulp. Solid-state co-cultivation of Bacillus sp. and B. halodurans FNP135 was optimized statistically by response surface methodology for the co-production of xylanase (X) and laccase (L). A significant increase in production of xylanase (2.1-fold, 1,685 IU/g) and laccase (2.04-fold, 2,270 nkat/g) was observed under optimized conditions viz. pH (10.5), inoculum size (10 + 10 %) and moisture:substrate ratio (0.8:1). Both the enzymes showed identical temperature and pH optima of 70 °C and 9, respectively, and were used for deinking of ONP pulp and biobleaching of kraft pulp. In case of ONP pulp deinking, the XL treatment increased brightness (11.8 %), freeness (17.8 %), breaking length (34.8 %), burst factor (2.77 %) and tear factor (2.4 %). In case of kraft pulp biobleaching, XL treatment showed a significant increase in brightness (13 %), whiteness (106.15 %) breaking length (49 %), burst factor (6.9 %), tear factor (23 %), and viscosity (11.68 %) and reduction in kappa number (15 %) after alkali extraction and peroxide stage. This enhancement of pulp properties revealed a synergistic effect of xylanase and laccase produced in one setup.

  12. Enzymatic pulp upgrade for producing high-value cellulose out of a Kraft paper pulp.

    Science.gov (United States)

    Hutterer, Christian; Kliba, Gerhard; Punz, Manuel; Fackler, Karin; Potthast, Antje

    2017-07-01

    The high-yield separation of polymeric parts from wood-derived lignocellulosic material is indispensable in biorefinery concepts. For the separation of cellulose and xylan from hardwood paper pulps to obtain pulps of high cellulose contents, simple alkaline extractions were found to be the most suitable technology, although having certain limitations. These are embodied by residual alkali resistant xylan incorporated in the pulp matrix. Further purification in order to produce pure cellulose with a low uniformity could be achieved selectively degrading residual xylan and depolymerizing the cellulose macromolecules by xylanase and cellulase. The latter help to adjust cellulose chain lengths for certain dissolving pulp grades while reducing the demand for ozone in subsequent TCF bleaching. Experiments applying different commercially available enzyme preparations revealed the dependency of xylanase performance on the residual xylan content in pulps being stimulated by additional cellulase usage. The action of the latter strongly depends on the cellulose allomorphy confirming the impact of the pulp morphology. Hence, the combined application of both types of enzymes offers a high potential for upgrading pulps in order to produce a pure and high-value cellulose product. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Alkaline peroxide treatment of ECF bleached softwood kraft pulps: part 2. effect of increased fiber charge on refining, wet-end application, and hornification

    Science.gov (United States)

    Zheng Dang; Thomas Elder; Jeffery S. Hsieh; Arthur J. Ragauskas

    2007-01-01

    The effect of increased fiber charge on refining, cationic starch adsorption, and hornification was examined. Two pulps were investigated: (1) a softwood (SW) kraft pulp (KP) which was bleached elementally chlorine-free (ECF) and sewed as control; and (2) a control pulp treated with alkaline peroxide, which had a higher fiber charge. It was shown that increased fiber...

  14. Delignification of eucalypt kraft pulp with manganese-substituted polyoxometalate assisted by fungal versatile peroxidase.

    Science.gov (United States)

    Marques, Gisela; Gamelas, José A F; Ruiz-Dueñas, Francisco J; del Rio, José C; Evtuguin, Dmitry V; Martínez, Angel T; Gutiérrez, Ana

    2010-08-01

    Oxidation of the manganese-substituted polyoxometalate [SiW(11)Mn(II)(H(2)O)O(39)](6-) (SiW(11)Mn(II)) to [SiW(11)Mn(III)(H(2)O)O(39)](5-) (SiW(11)Mn(III)), one of the most selective polyoxometalates for the kraft pulp delignification, by versatile peroxidase (VP) was studied. First, SiW(11)Mn(II) was demonstrated to be quickly oxidized by VP at room temperature in the presence of H(2)O(2) (K(m)=6.4+/-0.7 mM and k(cat)=47+/-2s(-1)). Second, the filtrate from eucalypt pulp delignification containing reduced polyoxometalate was treated with VP/H(2)O(2), and 95-100% reoxidation was attained. In this way, it was possible to reuse the liquor from a first SiW(11)Mn(III) stage for further delignification, in a sequence constituted by two polyoxometalate stages, and a short intermediate step consisting of the addition of VP/H(2)O(2) to the filtrate for SiW(11)Mn(II) reoxidation. When the first ClO(2) stage of a conventional bleaching sequence was substituted by the two-stage delignification with polyoxometalate (assisted by VP) a 50% saving in ClO(2) was obtained for similar mechanical strength of the final pulp. (c) 2010 Elsevier Ltd. All rights reserved.

  15. Process for purification of waste water produced by a Kraft process pulp and paper mill

    Science.gov (United States)

    Humphrey, M. F. (Inventor)

    1979-01-01

    The water from paper and pulp wastes obtained from a mill using the Kraft process is purified by precipitating lignins and lignin derivatives from the waste stream with quaternary ammonium compounds, removing other impurities by activated carbon produced from the cellulosic components of the water, and then separating the water from the precipitate and solids. The activated carbon also acts as an aid to the separation of the water and solids. If recovery of lignins is also desired, then the precipitate containing the lignins and quaternary ammonium compounds is dissolved in methanol. Upon acidification, the lignin is precipitated from the solution. The methanol and quaternary ammonium compound are recovered for reuse from the remainder.

  16. Caffeic acid production by simultaneous saccharification and fermentation of kraft pulp using recombinant Escherichia coli.

    Science.gov (United States)

    Kawaguchi, Hideo; Katsuyama, Yohei; Danyao, Du; Kahar, Prihardi; Nakamura-Tsuruta, Sachiko; Teramura, Hiroshi; Wakai, Keiko; Yoshihara, Kumiko; Minami, Hiromichi; Ogino, Chiaki; Ohnishi, Yasuo; Kondo, Ahikiko

    2017-07-01

    Caffeic acid (3,4-dihydroxycinnamic acid) serves as a building block for thermoplastics and a precursor for biologically active compounds and was recently produced from glucose by microbial fermentation. To produce caffeic acid from inedible cellulose, separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) reactions were compared using kraft pulp as lignocellulosic feedstock. Here, a tyrosine-overproducing Escherichia coli strain was metabolically engineered to produce caffeic acid from glucose by introducing the genes encoding a 4-hydroxyphenyllactate 3-hydroxylase (hpaBC) from Pseudomonas aeruginosa and tyrosine ammonia lyase (fevV) from Streptomyces sp. WK-5344. Using the resulting recombinant strain, the maximum yield of caffeic acid in SSF (233 mg/L) far exceeded that by SHF (37.9 mg/L). In the SSF with low cellulase loads (≤2.5 filter paper unit/g glucan), caffeic acid production was markedly increased, while almost no glucose accumulation was detected, indicating that the E. coli cells experienced glucose limitation in this culture condition. Caffeic acid yield was also negatively correlated with the glucose concentration in the fermentation medium. In SHF, the formation of by-product acetate and the accumulation of potential fermentation inhibitors increased significantly with kraft pulp hydrolysate than filter paper hydrolysate. The combination of these inhibitors had synergistic effects on caffeic acid fermentation at low concentrations. With lower loads of cellulase in SSF, less potential fermentation inhibitors (furfural, 5-hydroxymethyfurfural, and 4-hydroxylbenzoic acid) accumulated in the medium. These observations suggest that glucose limitation in SSF is crucial for improving caffeic acid yield, owing to reduced by-product formation and fermentation inhibitor accumulation.

  17. Effects of black liquor shocks on activated sludge treatment of bleached kraft pulp mill wastewater.

    Science.gov (United States)

    Morales, Gabriela; Pesante, Silvana; Vidal, Gladys

    2015-01-01

    Kraft pulp mills use activated sludge systems to remove organic matter from effluents. Process streams may appear as toxic spills in treatment plant effluents, such as black liquor, which is toxic to microorganisms of the activated sludge. The present study evaluates the effects of black liquor shocks in activated sludge systems. Four black liquor shocks from 883 to 3,225 mg chemical oxygen demand-COD L(-1) were applied during 24 hours in a continuously operating lab-scale activated sludge system. Removal efficiencies of COD, color and specific compounds were determined. Moreover, specific oxygen uptake rate (SOUR), sludge volumetric index (SVI) and indicator microorganisms were evaluated. Results show that the addition of black liquor caused an increase in COD removal (76-67%) immediately post shock; followed two days later by a decrease (-19-50%). On the other hand, SOUR ranged between 0.152 and 0.336 mgO2 g(-1) volatile suspended solids-VSS• min(-1) during shocks, but the initial value was reestablished at hour 24. When the COD concentration of the shock was higher than 1,014 mg/L, the abundance of stalked ciliates and rotifers dropped. Finally, no changes in SVI were observed, with values remaining in the range 65.8-40.2 mL g(-1) total suspended solids-TSS during the entire operating process. Based on the results, the principal conclusion is that the activated sludge system with the biomass adapted to the kraft pulp effluent could resist a black liquor shock with 3,225 mgCOD L(-1) of concentration during 24 h, under this study's conditions.

  18. Comparative bacterial degradation and detoxification of model and kraft lignin from pulp paper wastewater and its metabolites

    Science.gov (United States)

    Abhishek, Amar; Dwivedi, Ashish; Tandan, Neeraj; Kumar, Urwashi

    2017-05-01

    Continuous discharge of lignin containing colored wastewater from pulp paper mill into the environment has resulted in building up their high level in various aquatic systems. In this study, the chemical texture of kraft lignin in terms of pollution parameters (COD, TOC, BOD, etc.) was quite different and approximately twofold higher as compared to model lignin at same optical density (OD 3.7 at 465 nm) and lignin content (2000 mg/L). For comparative bacterial degradation and detoxification of model and kraft lignin two bacteria Citrobacter freundii and Serratia marcescens were isolated, screened and applied in axenic and mixed condition. Bacterial mixed culture was found to decolorize 87 and 70 % model and kraft lignin (2000 mg/L), respectively; whereas, axenic culture Citrobacter freundii and Serratia marcescens decolorized 64, 60 % model and 50, 55 % kraft lignin, respectively, at optimized condition (34 °C, pH 8.2, 140 rpm). In addition, the mixed bacterial culture also showed the removal of 76, 61 % TOC; 80, 67 % COD and 87, 65 % lignin from model and kraft lignin, respectively. High pollution parameters (like TOC, COD, BOD, sulphate) and toxic chemicals slow down the degradation of kraft lignin as compared to model lignin. The comparative GC-MS analysis has suggested that the interspecies collaboration, i.e., each bacterial strain in culture medium has cumulative enhancing effect on growth, and degradation of lignin rather than inhibition. Furthermore, toxicity evaluation on human keratinocyte cell line after bacterial treatment has supported the degradation and detoxification of model and kraft lignin.

  19. Cellulose fibril aggregation studies of eucalyptus dissolving pulps using atomic force microscopy

    CSIR Research Space (South Africa)

    Chunilall, Viren

    2006-11-01

    Full Text Available STUDIES OF Eucalyptus DISSOLVING PULPS USING ATOMIC FORCE MICROSCOPY V. Chunilall1, J.Wesley-Smith2, T. Bush1 1CSIR, Forestry and Forest Product Research Centre, P.O. Box 17001, Congella, 4013, South Africa. 2Electron Microscope Unit, University of Kwa... pulp using atomic force microscopy (AFM) have reported increased cellulose fibril aggregation during processing, and a concomitant decrease in surface area available for chemical reaction1,2. These findings were subsequently confirmed...

  20. Development of a combined piezoresistive pressure and temperature sensor using a chemical protective coating for Kraft pulp digester process monitoring

    Science.gov (United States)

    Mohammadi, Abdolreza R.; Bennington, Chad P. J.; Chiao, Mu

    2011-01-01

    We have developed an integrated piezoresistive pressure and temperature sensor for multiphase chemical reactors, primarily Kraft pulp digesters (pH 13.5, temperatures up to 175 °C, reaching a local maximum of 180 °C and pressures up to 2 MPa). The absolute piezoresistive pressure sensor consisted of a large square silicon diaphragm (1000 × 1000 µm2) and high resistance piezoresistors (10 000 Ω). A 4500 Ω buried piezoresistive wire was patterned on the silicon chip to form a piezoresistive temperature sensor which was used for pressure sensor compensation and temperature measurement. A 4 µm thick Parylene HT® coating, a chemically resistant epoxy and a silicone conformal coating were deposited to passivate the pressure sensor against the caustic environment in Kraft digesters. The sensors were characterized up to 2 MPa and 180 °C in an environment chamber. A maximum thermal error of ±0.72% full-scale output (FSO), an average sensitivity of 0.116 mV (V kPa)-1 and a power consumption of 0.3 mW were measured in the pressure sensor. The sensors' resistances were measured before and after test in a Kraft pulping cycle and showed no change in their values. SEM pictures and topographical surfaces were also analyzed before and after pulp liquor exposure and showed no observable changes.

  1. Morphological development of cellulose fibrils of a bleached eucalyptus pulp by mechanical fibrillation

    Science.gov (United States)

    Q.Q. Wang; J.Y. Zhu; R. Gleisner; T.A. Kuster; U. Baxa; S.E. McNeil

    2012-01-01

    This study reports the production of cellulose nanofibrils (CNF) from a bleached eucalyptus pulp using a commercial stone grinder. Scanning electronic microscopy and transmission electronic microscopy imaging were used to reveal morphological development of CNF at micro and nano scales, respectively. Two major structures were identified (1) highly kinked, naturally...

  2. Modification of eucalyptus pulp fiber using silane coupling agents with aliphatic side chains of different length

    Science.gov (United States)

    The objective of this work was to evaluate the effect of three silane coupling agents with different aliphatic chain lengths on the hydrophobicity of eucalyptus pulp fiber. The three silanes coupling agents used (isobutyltrimethoxysilane, methyltrimethoxysilane, and n-octyltriethoxysilane [OTES]) we...

  3. Optical property analysis of thermally and photolytically aged Eucalyptus Camaldulensis chemithermomechanical pulp (CTMP)

    Science.gov (United States)

    Yao Chen; Yongming Fan; Mandla A. Tshabalala; Nicole M. Stark; Jianmin Gao

    2012-01-01

    To investigate the optical properties of chemithermomechanical pulp (CTMP) from Eucalyptus camaldulensis, one group of samples of CTMP was aged by heating, and another group was first subjected to bleaching with different bleaching agents, and then aging by exposure to sunlight. Chromophores were analyzed using diffuse reflectance UV-Vis spectra (...

  4. Colour and chloride removal from kraft pulp mill effluent using ion exchange

    International Nuclear Information System (INIS)

    Yun, G.; Ikehata, K.; Buchanan, I.D.

    2002-01-01

    Two weakly basic ion exchange resins (WBA) and seven strongly basic ion exchange resins (SBA) were evaluated on a bench scale for colour and chloride ion removal from kraft pulp mill effluent. Chloride ion was selected as a surrogate for non-process anions. Batch testing was carried out to determine effective resins and regenerants for colour and chloride removal. Although all of the WBA and SBA tested removed colour from the effluent to some extent, the results from the screening tests indicate that three SBA (IRA958, IRA458 and IRA900) have higher potential for complete removal of colour from the effluent. The three resins were successfully regenerated to nearly their original colour removal capacity using 1 N NaOH combined with 1 N NaCl. A macroporous acrylic SBA, IRA958, exhibited the highest average exchange capacity of the resins tested during three colour removal and two regeneration cycles. IRN78 and 4400OH, gel-type styrene-divinylbenzene SBA in the hydroxide form, were found to be effective for chloride removal. Breakthrough studies were conducted at various flow rates through columns of differing bed depths. The effectiveness of the selected resins and regenerating solutions was confirmed with these studies for both colour and chloride removal. (author)

  5. Lignin Peroxidase Activity Is Not Important in Biological Bleaching and Delignification of Unbleached Kraft Pulp by Trametes versicolor

    Science.gov (United States)

    Archibald, Frederick S.

    1992-01-01

    The discovery in 1983 of fungal lignin peroxidases able to catalyze the oxidation of nonphenolic aromatic lignin model compounds and release some CO2 from lignin has been seen as a major advance in understanding how fungi degrade lignin. Recently, the fungus Trametes versicolor was shown to be capable of substantial decolorization and delignification of unbleached industrial kraft pulps over 2 to 5 days. The role, if any, of lignin peroxidase in this biobleaching was therefore examined. Several different assays indicated that T. versicolor can produce and secrete peroxidase proteins, but only under certain culture conditions. However, work employing a new lignin peroxidase inhibitor (metavanadate ions) and a new lignin peroxidase assay using the dye azure B indicated that secreted lignin peroxidases do not play a role in the T. versicolor pulp-bleaching system. Oxidative activity capable of degrading 2-keto-4-methiolbutyric acid (KMB) appeared unique to ligninolytic fungi and always accompanied pulp biobleaching. PMID:16348775

  6. Enzymatic polymerisation and effect of fractionation of dissolved lignin from Eucalyptus globulus Kraft liquor.

    Science.gov (United States)

    Gouveia, S; Fernández-Costas, C; Sanromán, M A; Moldes, D

    2012-10-01

    The potential ability of the laccase from Myceliophthora thermophila, either alone or with low molecular weight (LMW) additives, to polymerise a dissolved lignin from Kraft liquor of eucalypt cooking was investigated. A previous study of enzymatic performance (activity and stability) was carried out using a design experiment methodology. In addition, Kraft dissolved lignin (KDL) was fractionated according to two different protocols (solvent extraction and acidic fractionation) in order to identify possible lignin fractions with noticeable polymerisation ability. KDL and its corresponding lignin fractions were treated with laccase and analysed by size exclusion chromatography and Fourier transform infrared spectroscopy. The results provide conclusive evidence of notable lignin modifications after incubation with laccase. Moreover, lignin fractionation allows to obtain lignin fractions with different chemical characteristics and polymerisation capability. Depending on the type of raw lignin, molecular weight can increase from 4- to 21-fold by means of laccase polymerisation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Biodegradation of kraft-lignin by Bacillus sp. isolated from sludge of pulp and paper mill.

    Science.gov (United States)

    Raj, Abhay; Reddy, M M Krishna; Chandra, Ram; Purohit, Hemant J; Kapley, Atya

    2007-12-01

    Eight bacterial strains were isolated on kraft lignin (KL) containing mineral salt medium (L-MSM) agar with glucose and peptone from the sludge of pulp and paper mill. Out of these, ITRC-S8 was selected for KL degradation, because of its fast growth at highest tested KL concentration and use of various lignin-related low molecular weight aromatic compounds (LMWACs) as sole source of carbon and energy. The bacterium was identified by biochemical tests as Gram-positive, rod-shaped and non-motile. Subsequent 16S rRNA gene sequencing showed 95% base sequence homology and it was identified as Bacillus sp. In batch experiments, a decrease in pH was observed initially followed by an increase till it reached an alkaline pH, which did not alter the culture growth significantly. The bacterium reduced the colour and KL content of 500 mg l(-1 )KL in MSM, in the presence of glucose and peptone, at pH 7.6, temperature 30 degrees C, agitation of 120 rpm and 6 days of incubation by 65 and 37% respectively. Significant reduction in colour and KL content in subsequent incubations is indicative of a co-metabolism mechanism, possibly due to initial utilization of added co-substrates for energy followed by utilization of KL as a co-metabolic. The degradation of KL by bacterium was confirmed by GC-MS analysis indicating formation of several LMWACs such as t-cinnamic acid, 3, 4, 5-trimethoxy benzaldehyde and ferulic acid as degradation products, which were not present in the control (uninoculated) sample. This favours the idea of biochemical modification of the KL polymer to a single monomer unit.

  8. Cellulose fibril aggregation studies of Eucalyptus dissolving pulps using atomic force microscopy

    CSIR Research Space (South Africa)

    Chunilall, Viren

    2006-11-01

    Full Text Available AGGREGATION STUDIES OF Eucalyptus DISSOLVING PULPS USING ATOMIC FORCE MICROSCOPY V. Chunilall1,3, J.Wesley-Smith2 and T. Bush1,3 1CSIR, Forestry and Forest Product Research Centre, P.O. Box 17001, Congella, 4013, South Africa. 2Electron Microscope... individual fibrils (cellulose molecules) and these, in turn, form fibril aggregates. Atomic force microscopy (AFM) has revealed that there is a marked increase in the lateral fibril aggregate dimension (LFAD) during pulping and bleaching1. Furthermore...

  9. Production of value added chemicals from xylan extraction in a Kraft pulp mill and the effect on pulp quality

    OpenAIRE

    Helmerius, Jonas; Vinblad von Walter, Jonas; Rova, Ulrika; Berglund, Kris; Hodge, David

    2008-01-01

    In the Kraft process hemicelluloses are lost in the cooking procedure to the black liquor stream, which is subsequently burnt in the recovery boiler to recover cooking chemicals and to produce steam and energy. Hemicelluloses have a low heating value compared to lignin and therefore recovery of hemicelluloses at an earlier stage of the Kraft process followed by biochemical conversionintohighvalue-conversion intohighvalue-into high value-added products might offer a muchbettereconomicopportuni...

  10. Are Eucalyptus clones advantageous for the pulp mill? | Clarke ...

    African Journals Online (AJOL)

    Dissolving pulp yield of clones varied from 43.8 to 45.6%, viscosity from 41.4 to 69.8cps and brightness from 43.7 to 50.7. Wood density was found to vary between clones from 460 to 570kg / m3, fibre diameter from 12.05 to 14.49:m and cell wall thickness from 2.40 to 2.64: m. Differences in wood and dissolving pulp ...

  11. Life cycle assessment of printing and writing paper produced from Eucalyptus globulus

    Energy Technology Data Exchange (ETDEWEB)

    Dias, A.; Lopes, E.; Arroja, L.; Capela, M.; Pereira, F. [Environmental and Planning Department, University of Aveiro (Portugal); Tome, M. [Agronomy Superior Institute, Lisboa (Portugal)

    2000-06-01

    The environmental impacts of the production of Portuguese printing and writing paper from Eucalyptus globulus kraft pulp were assessed using Life Cycle Assessment (LCA). The system under study includes forestry, pulp production, paper production, wastepaper final disposal, transports and production of energy, chemicals and fuels. The results are presented and discussed at inventory analysis and impact assessment levels. The results suggest that the pulp and paper production processes contribute significantly to almost all of the analysed inventory parameters and impact assessment categories. (orig.)

  12. Alkaline peroxide treatment of ECF bleached softwood kraft pulps. Part 1. characterizing the effect of alkaline peroxide treatment on carboxyl groups of fibers

    Science.gov (United States)

    Zheng Dang; Thomas Elder; Arthur J. Ragauskas

    2007-01-01

    The influence of alkaline peroxide treatment has been characterized on elementally chlorine-free (ECF) bleached softwood (SW) kraft pulp. The results indicate that fiber charge increased with an increase in peroxide charge: a maximum fiber charge increment of 16.6% was obtained with 8.0% more peroxide charge on oven-dried (0.d.) pulp at 60.0°C. Two primary bleaching...

  13. A Cost-Benefit Assessment of Gasification-Based Biorefining in the Kraft Pulp and Paper Industry

    Energy Technology Data Exchange (ETDEWEB)

    Eric D. Larson; Stefano Consonni; Ryan E. Katofsky; Kristiina Iisa; W. James Frederick

    2007-03-31

    Production of liquid fuels and chemicals via gasification of kraft black liquor and woody residues (''biorefining'') has the potential to provide significant economic returns for kraft pulp and paper mills replacing Tomlinson boilers beginning in the 2010-2015 timeframe. Commercialization of gasification technologies is anticipated in this period, and synthesis gas from gasifiers can be converted into liquid fuels using catalytic synthesis technologies that are in most cases already commercially established today in the ''gas-to-liquids'' industry. These conclusions are supported by detailed analysis carried out in a two-year project co-funded by the American Forest and Paper Association and the Biomass Program of the U.S. Department of Energy. This work assessed the energy, environment, and economic costs and benefits of biorefineries at kraft pulp and paper mills in the United States. Seven detailed biorefinery process designs were developed for a reference freesheet pulp/paper mill in the Southeastern U.S., together with the associated mass/energy balances, air emissions estimates, and capital investment requirements. Commercial (''Nth'') plant levels of technology performance and cost were assumed. The biorefineries provide chemical recovery services and co-produce process steam for the mill, some electricity, and one of three liquid fuels: a Fischer-Tropsch synthetic crude oil (which would be refined to vehicle fuels at existing petroleum refineries), dimethyl ether (a diesel engine fuel or LPG substitute), or an ethanol-rich mixed-alcohol product. Compared to installing a new Tomlinson power/recovery system, a biorefinery would require larger capital investment. However, because the biorefinery would have higher energy efficiencies, lower air emissions, and a more diverse product slate (including transportation fuel), the internal rates of return (IRR) on the incremental capital investments would be

  14. Purification, characterization and thermostability improvement of xylanase from Bacillus amyloliquefaciens and its application in pre-bleaching of kraft pulp.

    Science.gov (United States)

    Kumar, Sharad; Haq, Izharul; Prakash, Jyoti; Singh, Sudheer Kumar; Mishra, Shivaker; Raj, Abhay

    2017-05-01

    Xylanases have important industrial applications but are most extensively utilized in the pulp and paper industry as a pre-bleaching agent. We characterized a xylanase from Bacillus amyloliquefaciens strain SK-3 and studied it for kraft pulp bleaching. The purified enzyme had a molecular weight of ~50 kDa with optimal activity at pH 9.0 and 50 °C. The enzyme showed good activity retention (85%) after 2 h incubation at 50 °C and pH 9.0. This enzyme obeyed Michaelis-Menten kinetics with regard to beechwood xylan with K m and V max values of 5.6 mg/ml, 433 μM/min/mg proteins, respectively. The enzyme activity was stimulated by Mn 2+ , Ca 2+ and Fe 2+ metal ions. Further, it also showed good tolerance to phenolics (2 mM) in the presence of syringic acid (no loss), cinnamic acid (97%), benzoic acid (94%) and phenol (97%) activity retention. The thermostability of xylanase was increased by 6.5-fold in presence of sorbitol (0.75 M). Further, pulp treated with 20U/g of xylanase (20IU/g) alone and with sorbitol (0.75M) reduced kappa number by 18.3 and 23.8%, respectively after 3 h reaction. In summary, presence of xylanase shows good pulp-bleaching activity, good tolerance to phenolics, lignin and metal ions and is amenable to thermostability improvement by addition of polyols. The SEM image showed significant changes on the surface of xylanase-treated pulp fiber as a result of xylan hydrolysis.

  15. Effect of Laccase-Mediated Biopolymer Grafting on Kraft Pulp Fibers for Enhancing Paper’s Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Lourdes Ballinas-Casarrubias

    2017-11-01

    Full Text Available High-resistance paper was manufactured by laccase-grafting of carboxymethyl cellulose (CMC and chitosan (CPX on Kraft pulp fiber. The reaction was mediated in the presence of laccase by one of the following polyphenols in the presence of air: gallic acid (GA, vanillic acid (VA and catechol (1,2–DHB. Enzyme was added at constant loading (24 kg ton−1, 1% pulp consistency, 0.005% CMC, pH = 6.3 ± 0.5 and 2 mM of mediator. CPX content was assessed at two levels (0% and 0.005%. Treated pulps were analyzed by different mechanical tests (ring crush, mullen, corrugating medium test (CMT flat crush of corrugating medium test and tension. An improvement in these parameters was obtained by biopolymer coupling and selected mediator. When using GA, three parameters increased more than 40%, while ring crush increased 120%. For the case of VA, properties were enhanced from 74% to 88% when CPX was added. For 1,2–DHB, there was not found a statistically significant difference between the results in the presence of CPX. Scanning electron microscopy, confocal microscopy, FTIR and 13C NMR were used in all papers in order to evaluate grafting. Hence, it was possible to correlate polymerization with an improvement of paper’s mechanical properties.

  16. Mineral phases of green liquor dregs, slaker grits, lime mud and wood ash of a Kraft pulp and paper mill

    International Nuclear Information System (INIS)

    Martins, Fernanda Machado; Munhoz Martins, Joaniel; Ferracin, Luiz Carlos; Cunha, Carlos Jorge da

    2007-01-01

    Four residues generated in a Kraft, pulp and paper plant, were characterized by X-ray fluorescence spectroscopy (XFA), powder X-ray diffraction (XRD), thermogravimmetric analysis (TG) and Fourier transform infrared spectroscopy (FTIR). A quantitative phase composition model, that accounts for the observed data and for the physico-chemical conditions of formation, was postulated for each material. Emphasis was given on the identification of the mineral components of each material. The green liquor dregs and the lime mud contain Calcite and Gipsite. The slaker grits contains Calcite, Portlandite, Pirssonite, Larnite and Brucite. The Calcite phase, present in the dregs and in the lime mud, has small amounts of magnesium replacing calcium. The wood ash contains Quartz as the major crystalline mineral phase

  17. Organosolv delignification of Eucalyptus globulus: Kinetic study of autocatalyzed ethanol pulping

    Energy Technology Data Exchange (ETDEWEB)

    Oliet, M.; Rodriguez, F.; Santos, A.; Gilarranz, M.A.; Garcia-Ochoa, F.; Tijero, J.

    2000-01-01

    The autocatalyzed delignification of Eucalyptus globulus in 50% ethanol (w/w) was modeled as the irreversible and consecutive dissolution of initial, bulk, and residual lignin. Their respective contributions to total lignin was estimated as 9, 75, and 16%. Isothermal pulping experiments were carried out to evaluate an empirical kinetic model among eight proposals corresponding to different reaction schemes. The calculated activation energy was found to be 96.5, 98.5, and 40.8 kJ/mol for initial, bulk, and residual delignification, respectively. The influence of hydrogen ion concentration was expressed by a power-law function model. The kinetic model developed here was validated using data from nonisothermal pulping runs.

  18. Selected resin acids in effluent and receiving waters derived from a bleached and unbleached kraft pulp and paper mill

    Science.gov (United States)

    Quinn, B.P.; Booth, M.M.; Delfino, J.J.; Holm, S.E.; Gross, T.S.

    2003-01-01

    Water samples were collected on three dates at 24 sites influenced by effluent from Georgia-Pacific's Palatka Pulp and Paper Mill Operation, a bleached and unbleached kraft mill near Palatka, Florida, USA. The sampling sites were located within the mill retention ponds, Rice Creek, and the St. John's River. Samples were analyzed by gas chromatography-mass spectrometry for abietic, dehydroabietic, and isopimaric acids, all of which are potentially toxic by-products of pulp production. Isopimaric acid concentrations greater than 12 mg/L were measured at the mill's effluent outfall but were less than 20 ??g/L at the end of Rice Creek. This result indicates that the waters of Rice Creek provide dilution or conditions conducive for degradation or sorption of these compounds. Large differences in resin acid concentrations were observed between sampling events. In two sampling events, the maximum observed concentrations were less than 2 mg/L for each analyte. In a third sampling event, all of the compounds were detected at concentrations greater than 10 mg/L. Data from the three sample dates showed that resin acid concentrations were below 20 ??g/L before the confluence of Rice Creek and the St. John's River in all cases.

  19. Post-treatment of anaerobic effluent by ozone and ozone/UV of a kraft cellulose pulp mill.

    Science.gov (United States)

    Chaparro, T R; Pires, E C

    2015-01-01

    Pulp and paper mill effluents represent a challenge when treatment technologies are considered, not only to reduce organic matter, but also to reduce the toxicological effects. Although anaerobic treatment has shown promising results, as well as advantages when compared with an aerobic system, this process alone is not sufficient to reduce recalcitrant compounds. Thus, an advanced oxidation process was applied. This experiment was performed to determine the effect of ozone and ozone/UV treating a horizontal anaerobic immobilized biomass reactor effluent from a kraft cellulose pulp mill for 306 days with an organic volumetric load of 2.33 kgCOD/m³/day. The removal of organic compounds was measured by the following parameters: adsorbable organically bound halogens (AOX), total phenols, chemical oxygen demand (COD), dissolved organic carbon and absorbance values in the UV-visible spectral region. Moreover, ecotoxicity and genotoxicity tests were conducted before and after treatment with ozone and ozone/UV. At an applied ozone dosage of 0.76 mgO₃/mgCOD and an applied UV dosage of 3.427 Wh/m(3), the organochlorine compounds measured as AOX reached removal efficiencies of 40%. Although the combination of ozone/UV showed better results in colour (79%) and total phenols (32%) compared with only ozone, the chronic toxicity and the genotoxicity that had already been removed in the anaerobic process were slightly increased.

  20. Physical and Mechanical Properties of Cellulose Nanofibril Films from Bleached Eucalyptus Pulp by Endoglucanase Treatment and Microfluidization

    Science.gov (United States)

    Wangxia Wang; Ronald C. Sabo; Michael D. Mozuch; Phil Kersten; J. Y. Zhu; Yongcan Jin

    2015-01-01

    A GH5 hyperthermostable endoglucanase (Ph-GH5) from the archaeon Pyrococcus horikoshii and a commercial endoglucanase (FR) were used to treat bleached eucalyptus pulp (BEP) fibers to produce cellulose nanofibrils (CNF) and subsequently to CNF films. TEM imaging indicated that Ph-GH5 produced longer and more entangled CNF than FR with the same number...

  1. The effects of wood storage on the chemical composition and indigenous microflora of eucalyptus species used in the pulping industry

    CSIR Research Space (South Africa)

    Ramnath, L

    2018-02-01

    Full Text Available eucalypt species [Eucalyptus nitens, E. grandis, and E. dunnii (of different site qualities)] wood and generated pulp was performed. This study aimed at determining the effects of wood storage at -20°C (for 6 months), by examining their chemical composition...

  2. Process integration study of a kraft pulp mill converted to an ethanol production plant – part B: Techno-economic analysis

    International Nuclear Information System (INIS)

    Fornell, Rickard; Berntsson, Thore; Åsblad, Anders

    2012-01-01

    In a previous study by the authors, energy efficiency measures in a conceptual kraft pulp mill converted to a lignocellulosic ethanol plant were investigated. The results suggested a number of different process designs which would give a substantial improvement in steam economy in the ethanol plant, compared to the original design. In the present study the different process designs are evaluated from an economic point-of-view, in order to determine if energy efficiency measures and increasing by-product sales decrease the production cost of ethanol from this specific process, or if the increased costs related to the implementation of these measures overshadow the benefits from increased by-product sales. The different energy efficiency measures are compared with less capital demanding alternatives (i.e. including low or no energy efficiency improvements) in order to assess the economic benefits of different strategies when converting a kraft pulp mill to ethanol production. The study indicates the economic importance of considering energy efficiency measures when repurposing a kraft pulp mill to an ethanol plant. It is also shown that, within the context of this study, a larger investment in measures will give better economic results than less capital demanding alternatives (with less improvement in energy efficiency). From an economic and energy efficiency viewpoint many of the suggested process designs will give approximately similar results, therefore the process design should be made based on other criteria (e.g. low complexity, low maintenance). - Highlights: ► Conversion of a kraft pulp mill to ethanol production. ► Heat integration of distillation/evaporation in a lignocellulosic ethanol plant. ► Energy efficiency measures lead to lower ethanol production cost. ► If capital costs and raw material prices are low the production cost could be as low as 365 €/m 3 EtOH.

  3. UV pretreatment of Alkaline Bleaching Wastewater from a Kraft Pulp and Paper Mill prior to Anaerobic Digestion in a Lab scale UASB Reactor

    OpenAIRE

    Karlsson, Marielle

    2013-01-01

    The effects of UV pretreatment on alkaline bleaching (EOP) wastewater from a kraft pulp and paper mill were investigated prior to anaerobic digestion (AD) in an upflow anaerobic sludge blanket (UASB) reactor. The aim was to enhance the methane production, increase the reduction of total organic carbon (TOC) and determine the best UV exposure time. The exposure time of 2.6 minutes partially degraded the organic material in the EOP wastewater since it generated higher biogas and methane product...

  4. Industrial hygiene aspects of a sampling survey at a bleached-kraft pulp mill in British Columbia.

    Science.gov (United States)

    Astrakianakis, G; Svirchev, L; Tang, C; Janssen, R; Anderson, J; Band, P; Le, N; Fang, R; Bert, J

    1998-10-01

    To validate exposure estimates used to investigate correlations between exposure and cancer risk, 1678 personal measurements were collected for 46 job titles during 73 day shifts at a bleached-kraft pulp mill. Measurements included shift-long average and short-term exposures to carbon monoxide, chlorine dioxide (ClO2), and hydrogen sulfide; and shift-long average exposures to calcium oxide and wood dust (WD). Overall results indicate low levels of exposure with a few noteworthy exceptions. Although ClO2 was the exclusive bleaching agent, 77 area samples indicated that chlorine (Cl2), not ClO2 was present in all areas apart from the chemical preparation area (chem-prep) and during a pulp spill. The highest shift-long exposures to Cl2 were measured in the chip yard and are attributed to uncontrolled stack emissions. Finally, WD samples collected from several laborers significantly exceeded regulatory limits, with the highest exposures measured in the steam and recovery area. For short-term exposures to ClO2 in chem-prep, 12 of 17 data-logging electro-chemical sensor sample results showed at least one peak that exceeded the short-term exposure limit of 0.3 ppm. The use of data-logging equipment quantified short-term exposures that previously had been characterized only anecdotally. The peaks were correlated with tasks and upset conditions and, given their transient nature, these exceedances could not have been detected using shift-long average-based sampling devices. Since the respiratory effects of significant short-term exposures to irritant gases such as Cl2 and ClO2 are well-documented, data-logging instruments are necessary to characterize exposures in the pulp and paper industry.

  5. Xylanase and mannanase enzymes from Streptomyces galbus NR and their use in biobleaching of softwood kraft pulp.

    Science.gov (United States)

    Kansoh, Amany L; Nagieb, Zeinat A

    2004-02-01

    Enzymatic pretreatment of softwood kraft pulp was investigated using xylanase and mannanase, singly or in combination, either sequentially or simultaneously. Enzymes were obtained from Streptomyces galbus NR that had been cultivated in a medium, containing either xylan of sugar cane bagasse or galactomannan of palm-seeds, when they were used as sole carbon sources from local wastes in fermentation media. No cellulase activity was detected. Incubation period, temperature, initial pH values and nature of nutritive constituents were investigated. Optimum production of both enzymes was achieved after 5 days incubation on a rotary shaker (200 rpm) at 35 degrees C and initial pH 7.0. Partial purification of xylanase and mannanase in the cultures supernatant were achieved by salting out at 40-60 and 60-80% ammonium sulphate saturation with a purification of 9.63- and 8.71-fold and 68.80 and 62.79% recovery, respectively. The xylanase and mannanase from S. galbus NR have optimal activity at 50 and 40 degrees C, respectively. Both enzymes were stable at a temperature up to 50 degrees C. Xylanase and mannanase showed highest activity at pH 6.5 and were stable from 5.0 to 8.0 and from 5.5 to 7.5, respectively. The partial purified enzymes preparations of xylanase and mannanase enzymes showed high bleaching activity, which is an important consideration for industry. Xylanase was found to be more effective for paper-bleaching than mannanase. When xylanase and mannanase were dosed together (simultaneously), both enzymes were able to enhance the liberation of reducing sugars and improve pulp bleachability, possibly as a result of nearly additive interactions. The simultaneous addition of both enzymes was more effective in pulp treatment than their sequential addition.

  6. Characterization of solid wastes from kraft pulp industry for ceramic materials development purposes; Caracterizacao de residuos solidos da industria de celulose tipo kraft visando sua aplicacao no desenvolvimento de materiais ceramicos

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, L.R.; Francisco, M.A.C.O.; Sagrillo, V.P.D.; Louzada, D.M.; Entringer, J.M.S. [Instituto Federal do Espirito Santo (IFES), Vitoria, ES (Brazil)

    2016-07-01

    The Kraft pulp industry generates a large amount of solid wastes. Due this large quantity, the target of this study is characterize inorganic solid wastes, dregs, grits and lime mud, from the step of reagents recovery of Kraft process, aiming evaluate the potentiality of their use as alternative raw material on development of ceramic materials. Initially, the wastes were dried and ground, then they were subjected to the following characterization techniques: pH analysis, particle size analysis, X ray fluorescence, X ray diffraction, differential thermal analysis and thermogravimetric analysis and scanning electron microscopy. According to the results, it may be concluded that these wastes could be used as raw material in production of red ceramic and luting materials. (author)

  7. Spectroscopic determination of anthraquinone in kraft pulping liquors using a membrane interface

    Science.gov (United States)

    X.S. Chai; X.T. Yang; Q.X. Hou; J.Y. Zhu; L.-G. Danielsson

    2003-01-01

    A spectroscopic technique for determining AQ in pulping liquor was developed to effectively separate AQ from dissolved lignin. This technique is based on a flow analysis system with a Nafion membrane interface. The AQ passed through the membrane is converted into its reduced form, AHQ, using sodium hydrosulfite. AHQ has distinguished absorption characteristics in the...

  8. RE-UTILIZATION OF INORGANIC SOLID WASTE (LIME MUD AS FOREST ROAD STABILIZER FROM THE CHEMICAL RECOVERY PROCESS IN KRAFT PULP MILL

    Directory of Open Access Journals (Sweden)

    Habip Eroğlu

    2005-04-01

    Full Text Available Waste handling is a concern in all pulp and paper mills. Best available techniques for reducing waste is to minimize the generation of solid waste and/or reuse these materials, wherever practicable. One of the most important solid wastes is lime mud which is generated from the kraft pulping in its chemical recovery process. This paper explores the composition of lime mud resulting from the chemical recovery unite of kraft pulp mill and investigation of this waste for re-using beneficially on sub grade and pavement of forest road as a alternative disposal method. Lime mud obtained from the re-causticising process in SEKA pulp mill that utilizes wheat straw and reed as the principal raw material was supplied with % 47 water content and its chemical and physical characterisations was performed according to standard methods. Dried waste to environmental condition was mixed with certain amount to composite cement for using on pavement and sandy clay, loamy clay and clay soils for enriching forest road sub grade properties. In order to investigate the lime mud addition on pavement and sub grade properties necessary physical tests were performed. As a consequence this study reveals that while waste of lime mud causes environmental and economical problem with conventional disposal techniques and/or abandoning to environment, this waste can be used as good stabilisation materials on forest road sub-grade and pavement without any environmental problem.

  9. Delignification of Pinus radiata kraft pulp by treatment with a yeast genetically modified to produce laccases; Deslignificacion de pasta kraft de Pinus radiata con una levadura geneticamente modificada para producir lacasa

    Energy Technology Data Exchange (ETDEWEB)

    Arana-Cuenca, A.; Tellez-Jurado, A.; Yague, S.; Ferminan, E.; Carbajo, J. M.; Dominguez, A.; Gonzalez, T.; Villar, J. C.; Gonzalez, A. E.

    2010-07-01

    Cellulose pulp bleaching is one of the main biotechnological applications of fungal laccases due to their capacity to degrade lignin from unbleached pulp. This application requires low cost enzyme production and higher enzyme concentrations than those obtained from the natural fungal producers. Heterologous expression of laccase in yeasts is an option for producing these enzymes on an industrial scale. In this work, we have demonstrated the heterologous expression of the cglcc1 gene, responsible for laccase production in the basidiomicetous fungus Coriolopsis gallica, in the yeast Kluyveromyces lactis. In order to know if the transformed yeast has delignificant capability, a Pinus radiata kraft pulp has been incubated with it. After the treatment, a significant decrease in kappa number (13%) and in lignin content (22%) was observed. These results showed the delignificant capability of this transformed yeast. It can be concluded that the use of genetically modified microorganisms that do not demonstrate cellulolitic activity can produce high laccase levels and delignify cellulose pulps with a potential applications in cellulose pulp bleaching. (Author) 25 refs.

  10. Pilot study investigating ambient air toxics emissions near a Canadian kraft pulp and paper facility in Pictou County, Nova Scotia.

    Science.gov (United States)

    Hoffman, Emma; Guernsey, Judith R; Walker, Tony R; Kim, Jong Sung; Sherren, Kate; Andreou, Pantelis

    2017-09-01

    Air toxics are airborne pollutants known or suspected to cause cancer or other serious health effects, including certain volatile organic compounds (VOCs), prioritized by the US Environmental Protection Agency (EPA). While several EPA-designated air toxics are monitored at a subset of Canadian National Air Pollution Surveillance (NAPS) sites, Canada has no specific "air toxics" control priorities. Although pulp and paper (P&P) mills are major industrial emitters of air pollutants, few studies quantified the spectrum of air quality exposures. Moreover, most NAPS monitoring sites are in urban centers; in contrast, rural NAPS sites are sparse with few exposure risk records. The objective of this pilot study was to investigate prioritized air toxic ambient VOC concentrations using NAPS hourly emissions data from a rural Pictou, Nova Scotia Kraft P&P town to document concentration levels, and to determine whether these concentrations correlated with wind direction at the NAPS site (located southwest of the mill). Publicly accessible Environment and Climate Change Canada data (VOC concentrations [Granton NAPS ID: 31201] and local meteorological conditions [Caribou Point]) were examined using temporal (2006-2013) and spatial analytic methods. Results revealed several VOCs (1,3-butadiene, benzene, and carbon tetrachloride) routinely exceeded EPA air toxics-associated cancer risk thresholds. 1,3-Butadiene and tetrachloroethylene were significantly higher (p towns and contribute to poor health in nearby communities.

  11. Radiation application for paper preservation: gamma irradiation at Eucalyptus pulp sheets

    International Nuclear Information System (INIS)

    Borrely, Sueli Ivone; Barbosa, Patricia S.M.; D'Almeida, Maria Luiza O.

    2009-01-01

    Ionizing radiation has been proposed in order to protect information and books that may be lost due to fungi and or insects infestation. In general restaurators are very worried about the maintenance of original properties of items to be treated. The selected technology must consider two points: type of biological contamination and contamination control. Fungi is one of the principal organism which grows well on papers. Once this infestation is installed on the paper it will signify spots, resistance loses and deterioration. The organisms feces introduces enzymes, organic acids and pigments to the contaminated material. Ionizing radiation from gamma sources were applied at laboratory sheets manufactured with commercial cellulose pulp. The subject of this present paper was to investigate the ideal radiation dose that is safe for keeping the paper quality. Laboratory sheets (75 g/m 2 ) were prepared in a TAPPI sheet former. Bleached sulphate Eucalyptus pulp, refined in laboratory PFI mill to 31 deg SR, was the raw material. The formed sheets were irradiated at IPEN's 60 Co Gammacell with 3 kGy up to 25 kGy. No significant changes were detected in paper samples irradiated up to 9 kGy. This is the radiation dose to be suggested. During irradiation the applied dose rate was 0.817 Gy/s. (author)

  12. Chemical pulping of waste pineapple leaves fiber for kraft paper production

    Directory of Open Access Journals (Sweden)

    Waham Ashaier Laftah

    2015-07-01

    Full Text Available The main objective of this study is to evaluate the implementation of acetone as a pulping agent for pineapple leaves. Mixtures of water and acetone with concentration of 1%, 3%, 5%, 7%, and 10% were used. The effects of soaking and delignification time on the paper properties were investigated. Thermal and physical properties of paper sheet were studied using thermogravimetric analysis (TGA and tearing resistance test respectively. The morphological properties were observed using microscope at 200× magnification. The paper sheet produced from pulping with 3% acetone concentration shows the highest mechanical properties. Papers strength was improved by increasing the delignification time. The delignification time was reduced by cooking the pineapple leaves at a temperature of 118 °C under applied pressure of 80 kPa which has remarkable effect on paper strength.

  13. Chemical pulping of waste pineapple leaves fiber for kraft paper production

    OpenAIRE

    Laftah, Waham Ashaier; Abdul Rahaman, Wan Aizan Wan

    2015-01-01

    The main objective of this study is to evaluate the implementation of acetone as a pulping agent for pineapple leaves. Mixtures of water and acetone with concentration of 1%, 3%, 5%, 7%, and 10% were used. The effects of soaking and delignification time on the paper properties were investigated. Thermal and physical properties of paper sheet were studied using thermogravimetric analysis (TGA) and tearing resistance test respectively. The morphological properties were observed using microscope...

  14. Effects of intensive silvicultural treatments on kraft pulp quality of loblolly and slash pine

    Science.gov (United States)

    Charles E. Courchene; Alexander Clark; Monique L. Belli; William Jason Cooper; Barry D. Shiver

    2000-01-01

    Intensive forest-management practices have been shown to greatly increase the growth rates of southern pines. A joint study was undertaken to evaluate the wood and pulp quality from fast-grown 14-year-old loblolly pine from the Piedmont and 17-year-old slash pine from the Coastal Plain. The properties were compared to 24-year-old plantation-grown controls. three sets...

  15. Integrating the processes of a Kraft pulp and paper mill and its supply chain

    International Nuclear Information System (INIS)

    Mesfun, Sennai; Toffolo, Andrea

    2015-01-01

    Highlights: • A process integration model that establishes material stream connections among typical Nordic forest industries is developed. • Potential benefit of the operating the different industries in one site is studied using pinch analysis. • Different scenarios considered to assess impact of prioritization on how to utilize excess biomass. • Results indicate large potential for improved biomass resource utilization. - Abstract: This paper investigates the possibility of combining different forest industries (a pulp and paper mill, its supply chain, and a wood-pellet plant) into an integrated industrial site in which they share a common heat and power utility. Advanced process integration and optimization techniques are used to study the site from both material and energy viewpoints. An existing pulp and paper mill is used as the site core plant and its pulp and paper production rates are kept fixed as they are in reality, while the other material flow links among the plants are based on the current industrial situation in Sweden. Different scenarios are evaluated in order to reflect the two main objectives that can be pursued (increased electricity production or biomass resource saving) and the two technologies that can be considered for the shared CHP system (boilers and product gas fired gas turbines). The corresponding non-integrated (standalone) configurations are compared to these scenarios to quantify the potential benefits of the integration. Investment opportunity is also calculated for the considered scenarios as an indicator of the economic convenience

  16. Assessment of status of white sucker (Catostomus commersoni) populations exposed to bleached kraft pulp mill effluent.

    Science.gov (United States)

    Miller, David H; Tietge, Joseph E; McMaster, Mark E; Munkittrick, Kelly R; Xia, Xiangsheng; Ankley, Gerald T

    2013-07-01

    Credible ecological risk assessments often need to include analysis of population-level impacts. In the present study, a predictive model was developed to investigate population dynamics for white sucker (Catostomus commersoni) exposed to pulp mill effluent at a well-studied site in Jackfish Bay, Lake Superior, Canada. The model uniquely combines a Leslie population projection matrix and the logistic equation to translate changes in the fecundity and the age structure of a breeding population of white sucker exposed to pulp mill effluent to alterations in population growth rate. Application of this density-dependent population projection model requires construction of a life table for the organism of interest, a measure of carrying capacity, and an estimation of the effect of stressors on vital rates. A white sucker population existing at carrying capacity and subsequently exposed to pulp mill effluent equivalent to a documented exposure experienced during the period 1988 to 1994 in Jackfish Bay would be expected to exhibit a 34% to 51% annual decrease in recruitment during the first 5 yr of exposure and approach a population size of 71% of carrying capacity. The Jackfish Bay study site contains monitoring data for biochemical endpoints in white sucker, including circulating sex steroid concentrations, that could be combined with population modeling to utilize the model demonstrated at the Jackfish Bay study site for investigation of other white sucker populations at sites that are less data-rich. Copyright © 2013 SETAC.

  17. Eucalyptus

    Science.gov (United States)

    ... Siberian ginseng, and others.Herbs that contain hepatotoxic pyrrolizidine alkaloids (PAs)Eucalyptus can increase the toxicity of herbs that contain hepatotoxic pyrrolizidine alkaloids (PAs). PAs can damage the liver. Herbs ...

  18. Anaerobic digestion of alkaline bleaching wastewater from a kraft pulp and paper mill using UASB technique.

    Science.gov (United States)

    Larsson, Madeleine; Truong, Xu-Bin; Björn, Annika; Ejlertsson, Jörgen; Bastviken, David; Svensson, Bo H; Karlsson, Anna

    2015-01-01

    Anaerobic digestion of alkaline kraft elemental chlorine-free bleaching wastewater in two mesophilic, lab-scale upflow anaerobic sludge bed reactors resulted in significantly higher biogas production (250±50 vs. 120±30 NmL g [Formula: see text]) and reduction of filtered total organic carbon (fTOC) (60±5 vs. 43±6%) for wastewater from processing of hardwood (HW) compared with softwood (SW). In all cases, the gas production was likely underestimated due to poor gas separation in the reactors. Despite changes in wastewater characteristics, a stable anaerobic process was maintained with hydraulic retention times (HRTs) between 7 and 14 h. Lowering the HRT (from 13.5 to 8.5 h) did not significantly affect the process, and the stable performance at 8.5 h leaves room for further decreases in HRT. The results show that this type of wastewater is suitable for a full-scale implementation, but the difference in methane potential between SW and HW is important to consider both regarding process dimensioning and biogas yield optimization.

  19. Excess heat from kraft pulp mills. Trade-offs between internal and external use in the case of Sweden. Part 2. Results for future energy market scenarios

    International Nuclear Information System (INIS)

    Joensson, Johanna; Berntsson, Thore; Svensson, Inger-Lise; Moshfegh, Bahram

    2008-01-01

    In this paper the trade-off between internal and external use of excess heat from a kraft pulp mill is investigated for four different future energy market scenarios. The work follows the methodology described in Svensson et al. [2008. Excess heat from kraft pulp mills: trade-offs between internal and external use in the case of Sweden - Part 1: methodology. Energy Policy, submitted for publication], where a systematic approach is proposed for investigating the potential for profitable excess heat cooperation. The trade-off is analyzed by economic optimization of an energy system model consisting of a pulp mill and an energy company (ECO). In the model, investments can be made, which increase the system's energy efficiency by utilization of the mill's excess heat, as well as investments that increase the electricity production. The results show that the trade-off depends on energy market prices, the district heating demand and the type of existing heat production. From an economic point of view, external use of the excess heat is preferred for all investigated energy market scenarios if the mill is studied together with an ECO with a small heat load. For the cases with medium or large district heating loads, the optimal use of excess heat varies with the energy market price scenarios. However, from a CO 2 emissions perspective, external use is preferred, giving the largest reduction of global emissions in most cases. (author)

  20. Excess heat from kraft pulp mills: Trade-offs between internal and external use in the case of Sweden-Part 1: Methodology

    International Nuclear Information System (INIS)

    Svensson, Inger-Lise; Joensson, Johanna; Berntsson, Thore; Moshfegh, Bahram

    2008-01-01

    Excess heat from a kraft pulp mill can be used either internally to increase the level of efficiency in the mill, or externally for example as district heating. This paper presents an approach to investigate the competition between external and internal use through modelling the pulp mill and an energy company (ECO) within the same system boundary. Three different sizes of ECOs with different district heating demands are studied. To investigate the competitiveness of using industrial excess heat as district heating compared with other heat production techniques, the option of investing in excess heat use is introduced, along with the possibility for the ECO to invest in biomass combined heat and power (CHP), waste CHP and natural gas combined cycle (NGCC). To evaluate the robustness of the model, alternative solutions are identified and will be used as a comparison to the optimal solutions. The model has been verified by comparing the results with previous studies concerning kraft pulp mills and with related studies regarding district heating and real ECOs. Finally, the approach presented in this part of the study will be used in the second part in order to investigate the trade-off between internal and external use of excess heat under different future energy market scenarios

  1. EFEITO DA QUALIDADE DA MADEIRA NO DESEMPENHO DA POLPAÇÃO KRAFT

    Directory of Open Access Journals (Sweden)

    Danila Morais de Carvalho

    2014-01-01

    Full Text Available The aim of this study was to evaluate the wood quality in the kraft pulping performance under two different pulping conditions at two delignification degrees based on results for the yield, brightness, viscosity, and k/ kappa corrected index. Eucalyptus wood (A, B, and C was analyzed about their physicochemical properties (basic and apparent density, insoluble and soluble lignin content, extractive content, ash and insoluble ash in hydrochloric acid and used for pulp production by modified kraft cooking, using two different pulping conditions: Condition I (PI - 16.5% effective alkali, 30% sulfidity, and 155º of cooking temperature; and Condition II (PII - 17.5% effective alkali, 32% sulfidity,and 147ºC cooking temperature. Both conditions were performed to kappa number 15.5 ± 0.5 and 18.0 ± 0.5. The following pulping parameters and pulp properties produced were evaluated: H factor, screened yield, viscosity, brightness, hexenuronic acid content, and the k/kappa corrected index. The A wood, which had lower extractives and lignin content in its constitution, as well as lower basic and apparent density when compared with B and C woods, showed good results for cooking parameters, especially the pulp produced at PII condition at kappa number 18.0 ± 0.5.Also, the A wood showed higher screened yield, brightness, and viscosity comparing to the other pulps produced. Those pulps produced with higher kappa number have lower k/kappa corrected index.

  2. Oxidative stress proteins as an indicator of a low quality of eucalyptus clones for the pulp and paper industry.

    Science.gov (United States)

    Britto, D S; Pirovani, C P; Gonzalez, E R; Silva, J F; Gesteira, A S; Cascardo, J C M

    2012-10-19

    Eucalyptus is a genus widely cultivated in many tropical and subtropical regions of the world as one of the main sources of raw materials for the pulp and paper industry. Identification of clones and selection of genotypes with desirable agronomic characteristics would be useful. We assessed eucalyptus full-sibs that varied in wood quality, using a combination of two-dimensional gel electrophoresis and mass spectrometry to identify differentially expressed proteins as candidates for quality markers. Thirty-one differently expressed proteins were identified, including three proteins of clone X1, four of clone X2, and 12 each of clones X3 and X4. These proteins are involved in various biological processes, including polyphosphate biosynthesis, catalytic activity, nucleotide excision repair, cellular metabolic processes, cell redox homeostasis, response to salt stress, response to temperature, oxidation and reduction processes, cellular water homeostasis, and protein phosphorylation. In the cambial region of each clone, the proteins ketol-acid reductoisomerase, uncharacterized protein MG428, receptor-like serine/threonine-protein kinase and a heat shock protein were found in larger quantities in clone X4 than in clone X1. These proteins are known to be related to protection against oxidative stress and biosynthesis of lignin. A high buildup of proteins involved in response to stress in the cambial region of eucalyptus would indicate clones with undesirable characteristics for use in the pulp and paper industry.

  3. Bio-conventional bleaching of kadam kraft-AQ pulp by thermo-alkali-tolerant xylanases from two strains of Coprinellus disseminatus for extenuating adsorbable organic halides and improving strength with optical properties and energy conservation.

    Science.gov (United States)

    Lal, Mohan; Dutt, Dharm; Tyagi, C H

    2012-04-01

    Two novel thermo-alkali-tolerant crude xylanases namely MLK-01 (enzyme-A) and MLK-07 (enzyme-B) from Coprinellus disseminatus mitigated kappa numbers of Anthocephalus cadamba kraft-AQ pulps by 32.5 and 34.38%, improved brightness by 1.5 and 1.6% and viscosity by 5.75 and 6.47% after (A)XE(1) and (B)XE(1)-stages, respectively. The release of reducing sugars and chromophores was the highest during prebleaching of A. cadamba kraft-AQ pulp at enzyme doses of 5 and 10 IU/g, reaction times 90 and 120 min, reaction temperatures 75 and 65°C and consistency 10% for MLK-01 and MLK-07, respectively. MLK-07 was more efficient than MLK01 in terms of producing pulp brightness, improving mechanical strength properties and reducing pollution load. MLK-01 and MLK-07 reduced AOX by 19.51 and 42.77%, respectively at 4% chlorine demands with an increase in COD and colour due to removal of lignin carbohydrates complexes. A. cadamba kraft-AQ pulps treated with xylanases from MLK-01 to MLK-07 and followed by CEHH bleaching at half chlorine demand (2%) showed a drastic reduction in brightness with slight improvement in mechanical strength properties compared to pulp bleached at 4% chlorine demand. MLK-01 reduced AOX, COD and colour by 43.83, 39.03 and 27.71% and MLK-07 by 38.34, 40.48 and 30.77%, respectively at half chlorine demand compared to full chlorine demand (4%). pH variation during prebleaching of A. cadamba kraft-AQ pulps with strains MLK-01 and MLK-07 followed by CEHH bleaching sequences showed a decrease in pulp brightness, AOX, COD and colour with an increase in mechanical strength properties, pulp viscosity and PFI revolutions to get a beating level of 35 ± 1 °SR at full chlorine demand.

  4. Isolation and characterization of bacterial strains Paenibacillus sp. and Bacillus sp. for kraft lignin decolorization from pulp paper mill waste.

    Science.gov (United States)

    Chandra, Ram; Singh, Shail; Krishna Reddy, M M; Patel, D K; Purohit, Hemant J; Kapley, Atya

    2008-12-01

    Eight aerobic bacterial strains were isolated from pulp paper mill waste and screened for tolerance of kraft lignin (KL) using the nutrient enrichment technique in mineral salt media (MSM) agar plate (15 g/L) amended with different concentrations of KL (100, 200, 300, 400, 500, 600 ppm) along with 1% glucose and 0.5% peptone (w/v) as additional carbon and nitrogen sources. The strains ITRC S6 and ITRC S8 were found to have the most potential for tolerance of the highest concentration of KL. These organisms were characterized by biochemical tests and further 16S rRNA gene (rDNA) sequencing, which showed 96.5% and 95% sequence similarity of ITRC S(6) and ITRC S(8) and confirmed them as Paenibacillus sp. and Bacillus sp., respectively. KL decolorization was routinely monitored with a spectrophotometer and further confirmed by HPLC analysis. Among eight strains, ITRC S(6) and ITRC S(8) were found to degrade 500 mg/L of KL up to 47.97% and 65.58%, respectively, within 144 h of incubation in the presence of 1% glucose and 0.5% (w/v) peptone as a supplementary source of carbon and nitrogen. In the absence of glucose and peptone, these bacteria were unable to utilize KL. The analysis of lignin degradation products by GC-MS analysis revealed the formation of various acids as lignin monomers which resulted in a decrease in pH and a major change in the chromatographic profile of the bacterial degraded sample as compared to the control clear indications of biochemical modification of KL due to the bacterial ligninolytic system by ITRC S(6), namely, acetic acid, propanoic acid, butanoic acid, guaiacol, hexanoic acid, and ITRC S(8), namely acetic acid, propanoic acid, ethanedioic acid, furan carboxylic acid, 2-propanoic acid, butanoic acid, 3-acetoxybutyric acid, propanedioic acid, acetoguiacone, 1,2,3-thiadiazole, 5-carboxaldixime, 4-hydroxy-3,5-dimethoxyphenol, and dibutyl phthalate, indicating the bacterium characteristic to degrade G and S units of lignin polymer.

  5. An efficient procedure to stably introduce genes into an economically important pulp tree (Eucalyptus grandis x Eucalyptus urophylla).

    Science.gov (United States)

    Tournier, Vincent; Grat, Sabine; Marque, Christiane; El Kayal, Walid; Penchel, Ricardo; de Andrade, Gisele; Boudet, Alain-Michel; Teulières, Chantal

    2003-08-01

    Regeneration problems are one of the main limitations preventing the wider application of genetic engineering strategies to the genus Eucalyptus. Seedlings from Eucalyptus grandis x Eucalyptus urophylla were selected according to their regeneration (adventitious organogenesis) and transformation capacity. After in vitro cloning, the best genotype of 250 tested was transformed via Agrobacterium tumefaciens. A cinnamyl alcohol dehydrogenase (CAD) antisense cDNA from Eucalyptus gunnii was transferred, under the control of the 35S CaMV promoter with a double enhancer sequence, into a selected genotype. According to kanamycin resistance and PCR verification, 120 transformants were generated. 58% were significantly inhibited for CAD activity, and nine exhibited the highest down-regulation, ranging from 69 to 78% (22% residual activity). Southern blot hybridisation showed a low transgene copy number, ranging from 1 to 4, depending on the transgenic line. Northern analyses on the 5-16 and 3-23 lines (respectively one and two insertion sites) demonstrated the antisense origin of CAD gene inhibition. With respectively 26 and 22% of residual CAD activity, these two lines were considered as the most interesting and transferred to the greenhouse for further analyses.

  6. Study of Cellulose-Rich Materials Recovered After Dissolution of Sulphite Pulp from South African Eucalyptus Wood in [C2mim][OAc]/co-Solvent Mixtures

    CSIR Research Space (South Africa)

    Tywabi, Z

    2017-09-01

    Full Text Available the structure of lignocellulosic materials. Mixtures of the IL 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc]) and dimethylsulfoxide (DMSO) or dimethylformamide (DMF) were used to dissolve South African eucalyptus raw (unbleached) and final (bleached) pulp...

  7. Formation of carbonyl groups on cellulose during ozone treatment of pulp: consequences for pulp bleaching.

    Science.gov (United States)

    Pouyet, Frédéric; Chirat, Christine; Potthast, Antje; Lachenal, Dominique

    2014-08-30

    The formation of carbonyl groups during the ozone treatment (Z) of eucalyptus (Eucalyptus grandis and Eucalyptus urophylla hybrid) kraft pulps and their behaviors during subsequent alkaline stages were investigated by the CCOA method with carbazole-9-carboxylic acid [2-(2-aminooxethoxy)-ethoxy] amide (CCOA) as the carbonyl-selective fluorescence label. Several pulp samples with or without lignin and hexenuronic acids (hexA) were used to elucidate the effects of these components when present in unbleached kraft pulp. Both hexA and lignin increased the formation of carbonyl groups on cellulose and hemicellulose during ozonation. It was concluded that radicals are likely formed when ozone reacts with either lignin or hexA. These carbonyl groups were involved in cellulose depolymerization during subsequent alkaline extraction stages with sodium hydroxide (E) and alkaline hydrogen peroxide (P, in ZEP or ZP). Their numbers decreased after E but increased during P when H2O2 was not stabilized enough. Several ways to minimize the occurrence of carbonyl group formation are suggested. Copyright © 2014. Published by Elsevier Ltd.

  8. Influence of High Shear Dispersion on the Production of Cellulose Nanofibers by Ultrasound-Assisted TEMPO-Oxidation of Kraft Pulp.

    Science.gov (United States)

    Loranger, Eric; Piché, André-Olivier; Daneault, Claude

    2012-09-10

    Cellulose nanofibers can be produced using a combination of TEMPO, sodium bromide (NaBr) and sodium hypochlorite, and mechanical dispersion. Recently, this process has been the subject of intensive investigation. However, studies on the aspects of mechanical treatment of this process remain marginal. The main objective of this study is to evaluate the high shear dispersion parameters (e.g., consistency, stator-rotor gap, recirculation rate and pH) and determine their influences on nanocellulose production using ultrasound-assisted TEMPO-oxidation of Kraft pulp. All nanofiber gels produced in this study exhibited rheological behaviors known as shear thinning. From all the dispersion parameters, the following conditions were identified as optimal: 0.042 mm stator-rotor gap, 200 mL/min recycle rate, dispersion pH of 7 and a feed consistency of 2%. High quality cellulose gel could be produced under these conditions. This finding is surely of great interest for the pulp and paper industry.

  9. Influence of High Shear Dispersion on the Production of Cellulose Nanofibers by Ultrasound-Assisted TEMPO-Oxidation of Kraft Pulp

    Directory of Open Access Journals (Sweden)

    Claude Daneault

    2012-09-01

    Full Text Available Cellulose nanofibers can be produced using a combination of TEMPO, sodium bromide (NaBr and sodium hypochlorite, and mechanical dispersion. Recently, this process has been the subject of intensive investigation. However, studies on the aspects of mechanical treatment of this process remain marginal. The main objective of this study is to evaluate the high shear dispersion parameters (e.g., consistency, stator-rotor gap, recirculation rate and pH and determine their influences on nanocellulose production using ultrasound-assisted TEMPO-oxidation of Kraft pulp. All nanofiber gels produced in this study exhibited rheological behaviors known as shear thinning. From all the dispersion parameters, the following conditions were identified as optimal: 0.042 mm stator-rotor gap, 200 mL/min recycle rate, dispersion pH of 7 and a feed consistency of 2%. High quality cellulose gel could be produced under these conditions. This finding is surely of great interest for the pulp and paper industry.

  10. Understanding the Nonproductive Enzyme Adsorption and Physicochemical Properties of Residual Lignins in Moso Bamboo Pretreated with Sulfuric Acid and Kraft Pulping.

    Science.gov (United States)

    Huang, Caoxing; He, Juan; Min, Douyong; Lai, Chenhuan; Yong, Qiang

    2016-12-01

    In this work, to elucidate why the acid-pretreated bamboo shows disappointingly low enzymatic digestibility comparing to the alkali-pretreated bamboo, residual lignins in acid-pretreated and kraft pulped bamboo were isolated and analyzed by adsorption isotherm to evaluate their extents of nonproductive enzyme adsorption. Meanwhile, physicochemical properties of the isolated lignins were analyzed and a relationship was established with non-productive adsorption. Results showed that the adsorption affinity and binding strength of cellulase on acid-pretreated bamboo lignin (MWLa) was significantly higher than that on residual lignin in pulped bamboo (MWLp). The maximum adsorption capacity of cellulase on MWLp was 129.49 mg/g lignin, which was lower than that on MWLa (160.25 mg/g lignin). When isolated lignins were added into the Avicel hydrolysis solution, the inhibitory effect on enzymatic hydrolysis efficiency of MWLa was found to be considerably stronger than that with MWLp. The cellulase adsorption on isolated lignins was correlated positively with hydrophobicity, phenolic hydroxyl group, and degree of condensation but negatively with surface charges and aliphatic hydroxyl group. These results suggest that the higher nonproductive cellulase adsorption and physicochemical properties of residual lignin in acid-pretreated bamboo may be responsible for its disappointingly low enzymatic digestibility.

  11. Uji Infeksi Mycosphaerella spp Terhadap Bibit Eucalyptus spp

    OpenAIRE

    Lidya Morita Sondang

    2009-01-01

    Tujuan penelitian ini adalah untuk mengetahui tingkat ketahanan 2 klon Eucalyptus spp yaitu Eucalyptus grandis x Eucalyptus pellita dan Eucalyptus grandis x Eucalyptus urophylla terhadap Mycosphaerella spp serta mengetahui virulensi Mycospaherella spp pada 2 kelas umur (2 dan 3 bulan) pada tanaman Eucalyptus spp. Penelitian ini dilaksanakan dengan pengambilan sampel bibit tanaman Eucalyptus grandis x Eucalyptus pellita dan Eucalyptus grandis x Eucalyptus urophylla dari pembibitan PT.Toba Pulp...

  12. 40 CFR Appendix E to Part 63 - Monitoring Procedure for Nonthoroughly Mixed Open Biological Treatment Systems at Kraft Pulp...

    Science.gov (United States)

    2010-07-01

    ... TOXCHEM (Environment Canada's Wastewater Technology Centre and Environmega, Ltd.) model, version 1.10, or... the Pulp and Paper Industry. Subpart S requires this procedure in § 63.453(p)(3) to be followed during...

  13. Anaerobic biodegradability and toxicity of wastewaters from chlorine and total chlorine-free bleaching of eucalyptus kraft pulps.

    NARCIS (Netherlands)

    Vidal, G.; Soto, M.; Field, J.; Mendez-Pampin, R.; Lema, J.M.

    1997-01-01

    Chlorine bleaching effluents are problematic for anaerobic wastewater treatment due to their high methanogenic toxicity and low biodegradability. Presently, alternative bleaching processes are being introduced, such as elemental chlorine-free (ECF) and total chlorine-free (TCF) bleaching. The

  14. PENENTUAN KOMPOSISI OPTIMUM BUBURAN KERTAS KRAFT LINER 150 GSM MENGGUNAKAN METODE MIXTURE EXPERIMENT (Studi kasus: Pabrik Pulp & Paper PT.Z

    Directory of Open Access Journals (Sweden)

    Johnson Saragih

    2015-11-01

    Full Text Available Tujuan dari penelitian ini adalah bagaimana caranya memilih komposisi dari campuran buburan kertas sehingga posisi optimum dapat tercapai, dengan tercapainya komposisi optimum tersebut diharapkan dapat  meningkatkan kualitas kertas yang diproduksi.Adapun komposisi buburan kertas yang ingin dicapai adalah  konsistensi sebesar untuk campuran ,pada campuran satu, tingkat freeness sebesar pada campuran dua dan tingkat internal bonding sebesar   pada campuran tiga. Percobaan dilakukan dengan metoda mixture experiment untuk sampel percobaan buburan kertas sebanyak 500 gr. Titik percobaan dibangkitkan dengan software minitab sebanyak 14 titik percobaan.Adapun komposisi campuran yang optimal diperoleh untuk total campuran diperoleh sebesar 71.23 % ( 356.15 gr Waste Paper, 8.72% (43.55gr Pulp (NUKP, 3.54% (17.7 gr Air, 5.7%(28.5 gr Rosin, 3.29 % (16.4 gr Aluminium Sulfat ( Al2(SO43, dan 7.55 %(37.75gr Starch. Dengan komposisi tersebut akan dihasilkan produk yang memenuhi spesifikasi yang telah ditetapkan perusahaan. Berdasarkan pengukuran kapabilitas proses  campuran satu, pada kertas kraft liner 150 gsm di perusahaan  untuk tingkat konsistensi, adalah sebesar 0.47 dan setelah dilakukan percobaan yang optimal, berubah menjadi 1.11 berarti  terdapat peningkatan sebesar 136.7 %.Pada campuran dua untuk tingkat freeness adalah 0.45 berubah menjadi 1.14 berarti meningkat sebesar 153.3 %, sedangkan pada campuran tiga untuk tingkat internal bonding dari 0.55 berubah menjadi 1.15 berarti meningkat sebesar 109 %. Kata kunci: mixture experiment; konsistensi; freeness; internal bonding Abstract The aim of the research are how to choose composition from pulp paper mix, so that optimum position can be achieved, with the achievement of optimum composition, it can be expected to increase quality of paper production.While the pulp paper composition to achieve are consistency as big as for mixing on first mix, freeness level as big as on second mix and internal

  15. INFLUÊNCIA DA DENSIDADE BÁSICA DA MADEIRA DE CLONES DE Eucalyptus grandis x Eucalyptus urophylla NA QUALIDADE DA POLPA BRANQUEADA

    Directory of Open Access Journals (Sweden)

    Sheila Rodrigues dos Santos

    2007-01-01

    Full Text Available The study analyzed the wood basic density effect in two Eucalyptus grandis x Eucalyptus urophylla hybrid clones (440 kg/m3 e 508 kg/m3 on bleached pulp quality (fiber dimensions and physical-mechanical properties. The woods performance on pulping, bleaching and beating results were analyzed. The Kraft pulping was carried out in forced circulation digester in order to obtain 17±1 kappa number targets. The pulps were bleached to 90±1 using delignification oxygen and D0EOPD1 bleaching sequence. Bleached pulp of low basic density clone showed, significantly, lowest revolutions number in the PFI mill to reach tensile index of 70 N.m/g, low Schopper Riegler degree and generated sheets with higher values to bulk and opacity. These characteristics and properties allow concluding that bleached pulp of low basic density clone was the most indicated to produce printing and writing sheets. The bleached pulp of high basic density clone showed higher values of bulk and capillarity Klemm and lower water retention value when analyzed without beating. The bleached pulp of high basic density clone showed more favorable characteristics to the production of tissue papers.

  16. Carbon Fibres from Kraft Lignin

    OpenAIRE

    Norberg, Ida

    2012-01-01

    Kraft lignin has a high potential for use in more valuable applications than its current use as fuel in pulp mills and integrated pulp and paper mills. The possibility of using kraft lignin, a green material with a carbon content of more than 60 %, for the manufacturing of carbon fibres was investigated in this thesis. The strong and lightweight carbon fibre material has many potential application areas, e.g. in cars; the main obstacle limiting its demand is the high production cost, with the...

  17. INTERFERENCE IN THE EUCALYPTUS PULP QUALITY AND YIELD DUE TO WOOD MULTIPLE USE

    Directory of Open Access Journals (Sweden)

    Alexandre Monteiro de Carvalho

    2004-07-01

    Full Text Available A 7-year plantation of Eucalyptus grandis x Eucalyptus urophylla hybrid established in the vicinity of Mogi-Guaçu/SP was evaluated, according to a simulation of multiple use of the wood. Part of the raw material produced was sent to sawn wood industry. The quality and yield of the cellulose produced in laboratory of three wood portions of the plantation was compared. In Treatment 1, the cellulose produced from the whole wood of the trees was evaluated; in Treatment 2 only the first portion of the tree was used, from wood of the soil base up to 4m height, wood that would be destined to sawnwood in a multiple use situation; finally, Treatment 3 evaluated the portion of the wood above 4 m of height. The possible interferences of multiple use of the wood in the yield and quality of the cellulose were evaluated. The results demonstrated that the retreat of the most vigorous logs of the trees didn't harm the quality and yield of the cellulose.

  18. Keawetan dan Keterawetan Kayu Ekaliptus (Eucalyptus urophylla) Umur 7 Tahun dari Areal HPHTI PT. Toba Pulp Lestari, Tbk

    OpenAIRE

    Sitepu, Odi Lorano

    2011-01-01

    The objection of this research was to know the natural durability effect of Eucalyptus urophylla wood of Subteran termite’s attact, retention and penetration of borat acid solution, and treatability of Eucalyptus urophylla. After preserving treatment, wood graved for 100 days. Percentation of weight loss was between 0,11%-0,52%. Eucalyptus urophylla can be classified as resistance wood of subteran termite’s attack. The preservative retention value of Eucalyptus urophylla wood was between 1,83...

  19. Treatment of real industrial wastewaters through nano-TiO2 and nano-Fe2O3 photocatalysis: case study of mining and kraft pulp mill effluents.

    Science.gov (United States)

    Nogueira, V; Lopes, I; Rocha-Santos, T A P; Gonçalves, F; Pereira, R

    2017-06-01

    High quantities of industrial wastewaters containing a wide range of organic and inorganic pollutants are being directly discharged into the environment, sometimes without proper treatment. Nanotechnology has a tremendous potential improving the existing treatments or even develop new treatment solutions. In this study, nano-TiO 2 or nano-Fe 2 O 3 was used for the photocatalytic treatment of kraft pulp mill effluent and mining effluent. The experiments with the organic effluent lead to reduction percentages of 93.3%, 68.4% and 89.8%, for colour, aromatic compounds and chemical oxygen demand, respectively, when treated with nano-TiO 2 /H 2 O 2 /UV and nano-Fe 2 O 3 /H 2 O 2 /UV, at pH 3.0. Significant removal of metals from the mining effluent was recorded but only for Zn, Al and Cd, the highest removal attained with 1.0 g L -1 of nano-TiO 2 /UV and nano-Fe 2 O 3 /UV. Regarding the toxicity of the organic effluent to Vibrio fischeri, it was reduced with the treatments combining the oxidant and the catalyst. However, for the inorganic effluent, the best reduction was achieved using 1.0 g L -1 of catalyst. In fact, the increase in dose of the catalyst, especially for nano-TiO 2 , enhanced toxicity reduction. Our results have shown that the use of these NMs seemed to be more effective in the organic effluent than in metal-rich effluent.

  20. Evaluation of the anaerobic degradation of black liquor from a Kraft pulp plant with addition of organic co-substrates.

    Science.gov (United States)

    Buzzini, A P; Sakamoto, I K; Varesche, M B; Pires, E C

    2009-01-01

    The purpose of this study was to assess the anaerobic degradation of black liquor with and without additional carbon sources. Batch experiments were conducted using black liquor, from an integrated pulp and paper mill adding ethanol, methanol and nutrients. The PCR/DGGE technique was used to characterize the structure of the microbial community. The addition of extra sources of carbon did not significantly influence the degradation of black liquor under the conditions evaluated and the microbial community was similar in all experiments. It was observed an increase in some members of the archaeal in reactors that had the best efficiencies for removal of black liquor (around 7.5%). Either ethanol or methanol can be used as co-substrates because the produce the same quantitative and qualitative effect.

  1. Basic density and pulp yield relationship with some chemical parameters in eucalyptus trees Densidade e rendimento em polpa celulósica e sua relação com alguns parâmetros químicos no eucalipto

    Directory of Open Access Journals (Sweden)

    Ana Maria Loureiro da Seca

    2006-12-01

    Full Text Available The objective of this work was to evaluate the use of basic density and pulp yield correlations with some chemical parameters, in order to differentiate an homogeneous eucalyptus tree population, in terms of its potential for pulp production or some other technological applications. Basic density and kraft pulp yield were determined for 120 Eucalyptus globulus trees, and the values were plotted as frequency distributions. Homogenized samples from the first and fourth density quartiles and first and fourth yield quartiles were submitted to total phenols, total sugars and methoxyl group analysis. Syringyl/guaiacyl (S/G and syringaldehyde/vanillin (S/V ratios were determined on the kraft lignins from wood of the same quartiles. The results show the similarity between samples from high density and low yield quartiles, both with lower S/G (3.88-4.12 and S/V (3.99-4.09 ratios and higher total phenols (13.3-14.3 g gallic acid kg-1 . Woods from the high yield quartile are statistically distinguished from all the others because of their higher S/G (5.15 and S/V (4.98 ratios and lower total phenols (8.7 g gallic acid kg-1 . Methoxyl group and total sugars parameters are more adequate to distinguish wood samples with lower density.O objetivo deste trabalho foi avaliar a aplicabilidade de correlações entre rendimento em polpa e densidade básica com alguns parâmetros químicos, para diferenciar uma população homogênea de árvores de eucalipto, em termos de capacidade de produção de polpa celulósica ou de outras aplicações. Determinou-se a densidade básica e o rendimento em polpa celulósica em 120 árvores de Eucalyptus globulus, e os resultados foram representados como distribuição de freqüências. Na madeira das árvores dos primeiro e quarto quartis de densidade e de rendimento, determinaram-se os teores de fenóis totais, açúcares totais e grupos metoxílicos. Nas respectivas ligninas kraft determinaram-se as razões seringilo

  2. UTILIZAÇÃO DE MISTURAS DE CAVACOS INDUSTRIAIS COM RESÍDUOS DE SERRARIA PROVENIENTES DE MADEIRAS DE Eucalyptus grandis DE DIFERENTES IDADES PARA PRODUÇÃO DE PASTA KRAFT

    Directory of Open Access Journals (Sweden)

    Angelina Maron

    2004-01-01

    Full Text Available Este trabalho estuda a viabilidade técnica do uso conjunto de resíduos de serraria (costaneiras dentre outros e topos de árvores de Eucalyptus grandis com 15 anos de idade, destinadas à produção de madeira sólida, com madeira de árvores de plantio industrial, com 7 anos de idade, destinadas à produção de pasta kraft. São apresentados modelos úteis à realização de estimativas de alturas total e comercial e de volumes de madeira comercial e adequadas para serraria, todos baseados no DAP. São fornecidos dados anatômicos, de densidade básica e de composição química de misturas desses tipos de materiais. Mostra-se que é tecnicamente viável realizar deslignificações kraft com misturas contendo madeira comercial de Eucalyptus grandis 7 anos com resíduo de serraria ou topos de árvores. A deslignificação kraft de resíduos de serraria resulta em perda rápida de rendimento, mas a pasta produzida sob as mesmas condições apresenta número Kappa menor que a de Eucalyptus grandis com 7 anos. A deslignificação de topos de árvores resulta em perda de rendimento bruto, mas o consumo específico de madeira é menor. Conforme aumenta a madeira de topo nas misturas, ocorre um aumento na densidade básica, o comprimento médio das fibras fica praticamente o mesmo e um pequeno aumento no teor de lignina; há diminuição nos extrativos em etanol, em água quente e na solubilidade em NaOH 1%. Diminui um pouco o rendimento bruto em pasta, mas praticamente não afeta o número Kappa, caindo sensivelmente o consumo específico de madeira. Com o aumento de madeira de resíduo de serraria das árvores nas misturas, praticamente não há efeito sobre a densidade básica, mas o comprimento médio das fibras aumenta, ocorrendo também um pequeno aumento no teor de lignina. Os extrativos em etanol, em água quente e na solubilidade em NaOH 1% diminuem. O rendimento bruto em pasta cai um pouco, mas com uma queda sensível no número Kappa

  3. Rice straw pulp obtained by using various methods.

    Science.gov (United States)

    Rodríguez, Alejandro; Moral, Ana; Serrano, Luis; Labidi, Jalel; Jiménez, Luis

    2008-05-01

    Rice straw was used as an alternative raw material to obtain cellulosics pulps. Pulping was done by using classics reagents as soda (with anthraquinone and parabenzoquinone as aditives), potassium hydroxide and Kraft process. The holocellulose, alpha-cellulose and lignin contents of rice straw (viz. 60.7, 41.2 and 21.9 wt%, respectively) are similar to those of some woody raw materials such as pine and eucalyptus, and various non-wood materials including olive tree prunings, wheat straw and sunflower stalks. Pulping tests were conducted by using soda, soda and anthraquinone at 1 wt%, soda and parabenzoquinone at 1 wt%, potassium hydroxide and sodium sulphate (Kraft process) under two different sets of operating conditions, namely: (a) a 10 wt% reagent concentration, 170 degrees C and 60 min; and (b) 15 wt% reagent, 180 degrees C and 90 min. The solid/liquid ratio was 6 in both cases. Paper sheets made from pulp extracted by cooking with soda (15 wt%) and AQ (1 wt%) at 180 degrees C and 90 min pulp exhibit the best drainage index, breaking length, stretch and burst index (viz. 23 degrees SR, 3494 m, 3.34% and 2.51 kN/g, respectively).

  4. Synthesis and characterization of kraft lignin-based epoxy resins

    OpenAIRE

    El Mansouri, Nour-Eddine; Yuan, Qiaolong; Huang, Farong

    2011-01-01

    Epoxidization is an interesting way to develop a new application of lignin and therefore to improve its application potential. In this work, kraft lignin-based epoxy resins were obtained by the epoxidization reaction, using the kraft lignin recovered directly from pulping liquor and modified by a methylolation reaction. The methylolated lignins were obtained by the reaction of original kraft lignin with formaldehyde and glyoxal, which is a less volatile and less toxic aldehyde. 1H-NMR spectro...

  5. 77 FR 55698 - National Emission Standards for Hazardous Air Pollutants From the Pulp and Paper Industry

    Science.gov (United States)

    2012-09-11

    ... for kraft, soda and semi-chemical pulping vent gases; sulfite pulping processes; and bleaching systems... vents, pulping process condensates) at chemical, mechanical, secondary fiber and non- wood pulp mills... chemical recovery processes at kraft, soda, sulfite and stand-alone semi- chemical pulp mills was...

  6. Estrogenicity and intersex in juvenile rainbow trout (Oncorhynchus mykiss) exposed to Pine/Eucalyptus pulp and paper production effluent in Chile

    International Nuclear Information System (INIS)

    Chiang, Gustavo; Barra, Ricardo; Díaz-Jaramillo, Mauricio; Rivas, Meyling; Bahamonde, Paulina; Munkittrick, Kelly R.

    2015-01-01

    Highlights: • Juvenile rainbow were exposed to Pine and Eucalyptus PPME along with an in situ bioassay downstream of the combined discharge. • Fish exposed to PPME showed induced levels of plasma vitellogenin and female gonad maturation. • Male fish showed intersex characteristics in laboratory and in situ assays. • Tertiary treated PPME from Eucalyptus production have stronger estrogenic effects on juvenile fish. - Abstract: Pulp and paper mill effluents (PPMEs) have been shown to increase gonad size, cause early maturation, and disrupt hormone functions in native and non-native Chilean fish. In this study, we assessed reproductive (plasma vitellogenin; VTG, gonad development) and metabolic (ethoxyresorufin-O-deethylase activity; EROD) end points, relative liver size (LSI) and condition factor (K) of juvenile female and male rainbow trout exposed to effluents. Unlike previous studies, which have focus either on the specific effects of effluent on fish in laboratory exposures or biotic population statuses downstream of discharge sites, we simultaneously assessed the impacts of PPMES on trout using two approaches: (1) laboratory exposures of tertiary treated PPME produced from processing Eucalyptus globulus or Pinus radiata; and (2) in situ bioassay downstream of the combined discharge of the same pulp mill. Despite an increase in the average gonadosomatic index (GSI) in exposed fish, no statistical differences in gonad size between exposed and unexposed individuals was detected. However, both female and male fish exposed to effluents showed significantly higher concentrations of plasma VTG, so more in fish exposed to Eucalyptus-based effluent when compared to Pinus PPME. In addition, male fish showed intersex characteristics in all exposure assays (Eucaliptus and Pinus) and, despite the low concentration of effluent in the river (<1% [v/v]), similar responses were observed in the caged fish. Finally, EROD activity was induced in both in situ exposures and

  7. Estrogenicity and intersex in juvenile rainbow trout (Oncorhynchus mykiss) exposed to Pine/Eucalyptus pulp and paper production effluent in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Gustavo, E-mail: gchiang@centromeri.cl [Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, NB E2L 4L5 (Canada); Barra, Ricardo [Aquatic Systems Research Unit, EULA–Chile Environmental Sciences Centre, University of Concepción, Concepcion (Chile); Díaz-Jaramillo, Mauricio [Laboratorio de Ecotoxicología y Contaminación Ambiental (ECoA), IIMyC-CONICET-UNMdP, Mar del Plata (Argentina); Rivas, Meyling [Department of Zoology, Faculty of Natural and Oceanographic Sciences, University of Concepcion, Concepcion (Chile); Bahamonde, Paulina; Munkittrick, Kelly R. [Canadian Rivers Institute and Department of Biology, University of New Brunswick, Saint John, NB E2L 4L5 (Canada)

    2015-07-15

    Highlights: • Juvenile rainbow were exposed to Pine and Eucalyptus PPME along with an in situ bioassay downstream of the combined discharge. • Fish exposed to PPME showed induced levels of plasma vitellogenin and female gonad maturation. • Male fish showed intersex characteristics in laboratory and in situ assays. • Tertiary treated PPME from Eucalyptus production have stronger estrogenic effects on juvenile fish. - Abstract: Pulp and paper mill effluents (PPMEs) have been shown to increase gonad size, cause early maturation, and disrupt hormone functions in native and non-native Chilean fish. In this study, we assessed reproductive (plasma vitellogenin; VTG, gonad development) and metabolic (ethoxyresorufin-O-deethylase activity; EROD) end points, relative liver size (LSI) and condition factor (K) of juvenile female and male rainbow trout exposed to effluents. Unlike previous studies, which have focus either on the specific effects of effluent on fish in laboratory exposures or biotic population statuses downstream of discharge sites, we simultaneously assessed the impacts of PPMES on trout using two approaches: (1) laboratory exposures of tertiary treated PPME produced from processing Eucalyptus globulus or Pinus radiata; and (2) in situ bioassay downstream of the combined discharge of the same pulp mill. Despite an increase in the average gonadosomatic index (GSI) in exposed fish, no statistical differences in gonad size between exposed and unexposed individuals was detected. However, both female and male fish exposed to effluents showed significantly higher concentrations of plasma VTG, so more in fish exposed to Eucalyptus-based effluent when compared to Pinus PPME. In addition, male fish showed intersex characteristics in all exposure assays (Eucaliptus and Pinus) and, despite the low concentration of effluent in the river (<1% [v/v]), similar responses were observed in the caged fish. Finally, EROD activity was induced in both in situ exposures and

  8. A combined process of activated carbon adsorption, ion exchange resin treatment and membrane concentration for recovery of dissolved organics in pre-hydrolysis liquor of the kraft-based dissolving pulp production process.

    Science.gov (United States)

    Shen, Jing; Kaur, Ishneet; Baktash, Mir Mojtaba; He, Zhibin; Ni, Yonghao

    2013-01-01

    To recover dissolved organics in pre-hydrolysis liquor (PHL) of the kraft-based dissolving pulp production process, a new combined process concept of sequential steps of activated carbon adsorption, ion exchange resin treatment, and membrane concentration, was proposed. The removal of lignin in the PHL was achieved in the activated carbon adsorption step, which also facilitates the subsequent operations, such as the membrane filtration and ion exchange resin treatment. The ion exchange resin treatment resulted in the removal/concentration of acetic acid, which opens the door for acetic acid recovery. The membrane filtration is to recover/concentrate the dissolved sugars. The combined process resulted in the production of PHL-based concentrate with relatively high concentration of hemicellulosic sugars, i.e., 22.13%. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Hygroscopic slaking of lime with steam or humid air. New energy effective lime slaking technology in kraft pulping; Hygroskopisk slaeckning av kalk med aanga eller fuktig luft. Ny energieffektiv teknik foer slaeckning av mesakalk i sulfatmassaindustrin

    Energy Technology Data Exchange (ETDEWEB)

    Lundqvist, Roland

    2005-12-15

    Lime stone is widely used in chemical recovery for regeneration of white liquor in kraft pulping. Slaked (hydrated) lime is used to convert (causticize) sodium carbonate into sodium hydroxide, whereby lime mud (calcium carbonate) precipitates from the solution. Lime mud is dried and reburned in a lime kiln, where burned lime (calcium oxide) is formed. The circle is closed when lime is slaked (hydrated) in green liquor in an exotherm reaction. Problems with traditional slaking method is that heat is recovered at low temperatures. With the method described in this report there is potential to increase heat recovery in the causticizing plant. The forecasted method means that lime is slaked with steam or humid air, for example combined with a lime mud drier and a lime kiln. The task has included slaking of burned lime with steam or humid hot air, on purpose to test a specific machine equipment in pilote scale, and to investigate temperatures and hydratization rates able to reach. Also the lime slaked with steam/humid air should be compared with burned lime slaked in green liquor when green liquor is causticized, and to investigate the dewatering properties of formed lime mud. The target group is pulp and paper industry using the kraft process. The tests have been performed at SMA Svenska Mineral AB plant (lime burning) at Sandarne Sweden in years 2004-2005. Hydrated lime of varying slaking rates has been produced at temperatures up to 270 deg C. Caustizicing being performed show that dewatering properties of lime mud formed is quite up to the standard of lime mud from burned lime slaked in green liquor. The apprehension, that the hygroscopic slaked lime should result in lime mud difficult to dewater, has not become true. Important experiences have come out which could be used as a base in further investigations.

  10. Infrared spectroscopy as alternative to wet chemical analysis to characterize Eucalyptus globulus pulps and predict their ethanol yield for a simultaneous saccharification and fermentation process.

    Science.gov (United States)

    Castillo, Rosario Del P; Baeza, Jaime; Rubilar, Joselyn; Rivera, Alvaro; Freer, Juanita

    2012-12-01

    Bioethanol can be obtained from wood by simultaneous enzymatic saccharification and fermentation step (SSF). However, for enzymatic process to be effective, a pretreatment is needed to break the wood structure and to remove lignin to expose the carbohydrates components. Evaluation of these processes requires characterization of the materials generated in the different stages. The traditional analytical methods of wood, pretreated materials (pulps), monosaccharides in the hydrolyzated pulps, and ethanol involve laborious and destructive methodologies. This, together with the high cost of enzymes and the possibility to obtain low ethanol yields from some pulps, makes it suitable to have rapid, nondestructive, less expensive, and quantitative methods to monitoring the processes to obtain ethanol from wood. In this work, infrared spectroscopy (IR) accompanied with multivariate analysis is used to characterize chemically organosolv pretreated Eucalyptus globulus pulps (glucans, lignin, and hemicellulosic sugars), as well as to predict the ethanol yield after a SSF process. Mid (4,000-400 cm(-1)) and near-infrared (12,500-4,000 cm(-1)) spectra of pulps were used in order to obtain calibration models through of partial least squares regression (PLS). The obtained multivariate models were validated by cross validation and by external validation. Mid-infrared (mid-IR)/NIR PLS models to quantify ethanol concentration were also compared with a mathematical approach to predict ethanol yield estimated from the chemical composition of the pulps determined by wet chemical methods (discrete chemical data). Results show the high ability of the infrared spectra in both regions, mid-IR and NIR, to calibrate and predict the ethanol yield and the chemical components of pulps, with low values of standard calibration and validation errors (root mean square error of calibration, root mean square error of validation (RMSEV), and root mean square error of prediction), high correlation

  11. Estrogenicity and intersex in juvenile rainbow trout (Oncorhynchus mykiss) exposed to Pine/Eucalyptus pulp and paper production effluent in Chile.

    Science.gov (United States)

    Chiang, Gustavo; Barra, Ricardo; Díaz-Jaramillo, Mauricio; Rivas, Meyling; Bahamonde, Paulina; Munkittrick, Kelly R

    2015-07-01

    Pulp and paper mill effluents (PPMEs) have been shown to increase gonad size, cause early maturation, and disrupt hormone functions in native and non-native Chilean fish. In this study, we assessed reproductive (plasma vitellogenin; VTG, gonad development) and metabolic (ethoxyresorufin-O-deethylase activity; EROD) end points, relative liver size (LSI) and condition factor (K) of juvenile female and male rainbow trout exposed to effluents. Unlike previous studies, which have focus either on the specific effects of effluent on fish in laboratory exposures or biotic population statuses downstream of discharge sites, we simultaneously assessed the impacts of PPMES on trout using two approaches: (1) laboratory exposures of tertiary treated PPME produced from processing Eucalyptus globulus or Pinus radiata; and (2) in situ bioassay downstream of the combined discharge of the same pulp mill. Despite an increase in the average gonadosomatic index (GSI) in exposed fish, no statistical differences in gonad size between exposed and unexposed individuals was detected. However, both female and male fish exposed to effluents showed significantly higher concentrations of plasma VTG, so more in fish exposed to Eucalyptus-based effluent when compared to Pinus PPME. In addition, male fish showed intersex characteristics in all exposure assays (Eucaliptus and Pinus) and, despite the low concentration of effluent in the river (<1% [v/v]), similar responses were observed in the caged fish. Finally, EROD activity was induced in both in situ exposures and laboratory assays at the higher PPME concentration (60-85% PPME). This study confirms estrogenic effects in Chilean fish exposed to PPME and the necessity for biological effects monitoring in addition to the assessment of physical-chemical endpoints as required in current government regulations. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Hygroscopic slaking of lime with steam or humid air. New energy effective lime slaking technology in kraft pulping; Hygroskopisk slaeckning av kalk med aanga eller fuktig luft. Ny energieffektiv teknik foer slaeckning av mesakalk i sulfatmassaindustrin

    Energy Technology Data Exchange (ETDEWEB)

    Lundqvist, Roland

    2003-07-15

    Lime stone is widely used in chemical recovery for regeneration of white liquor in kraft pulping. Slaked (hydrated) lime is used to convert (causticize) sodium carbonate into sodium hydroxide, whereby lime mud (calcium carbonate) precipitates from the solution. Lime mud is dried and reburned in a lime kiln, where burned lime (calcium oxide) is formed. The circle is closed when lime is slaked (hydrated) in green liquor in an exotherm reaction. Problems with traditional slaking method is that heat is recovered at low temperatures. With the method described in this report there is potential to increase heat recovery in the causticizing plant. The forecasted method means that lime is slaked with steam or humid air, for example combined with a lime mud drier and a lime kiln. The task has included slaking of burned lime with steam or humid hot air, on purpose to test a specific machine equipment in pilote scale, and to investigate temperatures and hydratization rates able to reach. Also the lime slaked with steam/humid air should be compared with burned lime slaked in green liquor when green liquor is causticized, and to investigate the dewatering properties of formed lime mud. The target group is pulp and paper industry using the kraft process. The tests have been performed at SMA Svenska Mineral AB plant (lime burning) at Sandarne Sweden in years 2004-2005. Project owner has been the Swedish company Torkapparater AB, and the project is performed inside the 'Vaermeforsk Program for Pulp and Paper Industry 2004-2005'. Other partners, besides SMA Svenska Mineral AB, has been Stora Enso Skoghalls Bruk, Carnot AB, AaF Process AB and KTH Energiprocesser. Hydrated lime of varying slaking rates has been produced at temperatures up to 270 deg C. Caustizicing being performed show that dewatering properties of lime mud formed is quite up to the standard of lime mud from burned lime slaked in green liquor. The apprehension, that the hygroscopic slaked lime should result

  13. Comparison of various pulping characteristic of Fraxinus angustifolia ...

    African Journals Online (AJOL)

    This study was carried out in order to investigate the suitability of ash (Fraxinus angustifolia Vahl.), a native tree (species) in Turkey, for pulp and paper making. Four pulping methods, which included NSSC, cold soda, kraft and kraft + anthraquinone pulping processes, were used for this study. The test materials were ...

  14. Chapter 6: Prehydrolysis Pulping with Fermentation Coproducts

    Science.gov (United States)

    T.H. Wegner; C.J. Houtman; A.W. Rudie; B.L. Illman; P.J. Ince; E.M. Bilek; T.W. Jeffries

    2013-01-01

    Although the term “integrateed biorefinery” is new, the concept has long been familiar to the pulp and paper industry, where processes include biomass boilers providing combined heat and power, and byproducts of pulping include turpentine, fatty acids and resin acids. In the dominant kraft (or sulfate) pulping process, dissolved lignin and chemicals from the pulp...

  15. The assessment of chromophores in bleached cellulosic pulps employing UV-Raman spectroscopy.

    Science.gov (United States)

    Loureiro, Pedro E G; Fernandes, António J S; Carvalho, M Graça V S; Evtuguin, Dmitry V

    2010-07-02

    UV-Resonance Raman (UV-RR) coupled with UV-visible Diffuse Reflectance (UV-vis DR) spectroscopy was applied to a solid-state study of chromophores in Eucalyptus globulus kraft cellulosic pulps bleached by chlorine dioxide and hydrogen peroxide. The UV-RR spectra were acquired at 325nm laser beam excitation, which was shown to be appropriate for selective analysis of chromophore structures in polysaccharides. The proposed approach allowed the monitoring of chromophores in pulps and to track the extent of polysaccharide oxidation. However, precaution was suggested while performing a quantitative analysis of chromophores at the characteristic band of approximately 1600cm(-1) because of charge transfer complexes (CTCs) that exist in the pulp. These CTCs can affect the intensity of the aforementioned band by diminishing the conjugate state in the chromophore moieties. The amount of carbonyl and carboxyl groups in polysaccharides correlated with the intensity of the band at 1093cm(-1). The analysis of UV-RR spectra revealed xylan as an important source of chromophores in eucalypt kraft pulp. Copyright 2010 Elsevier Ltd. All rights reserved.

  16. Understanding pulp delignification by laccase-mediator systems through isolation and characterization of lignin-carbohydrate complexes.

    Science.gov (United States)

    Du, Xueyu; Li, Jiebing; Gellerstedt, Göran; Rencoret, Jorge; Del Río, José C; Martínez, Angel T; Gutiérrez, Ana

    2013-09-09

    The effects and mechanism of pulp delignification by laccases in the presence of redox mediators have been investigated on unbleached eucalyptus kraft pulp treated with laccases from Pycnoporus cinnabarinus (PcL) and Myceliophthora thermophila (MtL) and 1-hydroxybenzotriazole (HBT) and methyl syringate (MeS) as mediators, respectively. Determination of the corrected κ number in eucalyptus pulps after the enzymatic treatments revealed that the PcL-HBT system exhibited a more remarkable delignification effect than the MtL-MeS system. To obtain further insight, lignin-carbohydrate complexes were fractionated and subsequently characterized by nuclear magnetic resonance, thioacidolysis (followed by gas chromatography and size exclusion chromatography), and pyrolysis-gas chromatography-mass spectrometry (pyrolysis-GC-MS) analyses before and after the enzymatic treatments and their controls. We can conclude that the laccase-mediator treatments altered the lignin structures in such a way that more lignin was recovered in the xylan-lignin fractions, as shown by Klason lignin estimation, with smaller amounts of both syringyl (S) and guaiacyl (G) uncondensed units, as shown by thioacidolysis and gas chromatography, especially after the PcL-HBT treatment. The laccase-mediator treatment produced oxidation at Cα and cleavage of Cα and Cβ bonds in pulp lignin, as shown by pyrolysis-GC-MS. The general mechanism of residual lignin degradation in the pulp by laccase-mediator treatments is discussed in light of the results obtained.

  17. Adição de antraquinona na polpação alcalina de Eucalyptus saligna

    Directory of Open Access Journals (Sweden)

    Lúcia Helena Jerônimo

    2000-01-01

    Full Text Available The present work evaluated different alkaline pulping conditions for Eucalyptus saligna wood. The objective was to evaluate the influence of the anthraquinone (AQ on the reduction of the total reduced sulfur (TRS in the aerial emissions, by reducing the sulfidity. The experiment consisted of 8 cooking with active alkali varying from 19 to 21%, sulfidity from 0 to 20% and anthraquinone from 0 to 0.1%, aiming to obtain kappa numbers in the range 15.5±1.5. The H factor was used to control the relation time/temperature along cooking. The addition of anthraquinone increased the delignification rate allowing sulfidity reduction. The kraft/AQ pulping with sulfidities of 5 and 10% presented satisfactory results, making it possible the replacement of conventional kraft cooking, giving a reduction in process sulfidity without harms in pulping. In spite of a slightly lower performance, the soda/AQ cooking has potential to be used where the smell is a critical problem in the industrial operation.

  18. VOC Control in Kraft Mills; FINAL

    International Nuclear Information System (INIS)

    Zhu, J.Y.; Chai, X.-S.; Edwards, L.L.; Gu, Y.; Teja, A.S.; Kirkman, A.G.; Pfromm, P.H.; Rezac, M.E.

    2001-01-01

    The formation of volatile organic compounds (VOCs), such as methanol, in kraft mills has been an environmental concern. Methanol is soluble in water and can increase the biochemical oxygen demand. Furthermore, it can also be released into atmosphere at the process temperatures of kraft mill-streams. The Cluster Rule of the EPA now requires the control of the release of methanol in pulp and paper mills. This research program was conducted to develop a computer simulation tool for mills to predict VOC air emissions. To achieve the objective of the research program, much effort was made in the development of analytical techniques for the analysis of VOC and determination of vapor liquid partitioning coefficient of VOCs in kraft mill-streams using headspace gas chromatography. With the developed analytical tool, methanol formation in alkaline pulping was studied in laboratory to provide benchmark data of the amount of methanol formation in pulping in kraft mills and for the validation of VOC formation and vapor-liquid equilibrium submodels. Several millwide air and liquid samplings were conducted using the analytical tools developed to validate the simulation tool. The VOC predictive simulation model was developed based on the basic chemical engineering concepts, i.e., reaction kinetics, vapor liquid equilibrium, combined with computerized mass and energy balances. Four kraft mill case studies (a continuous digester, two brownstock washing lines, and a pre-evaporator system) are presented and compared with mill measurements. These case studies provide valuable, technical information for issues related to MACT I and MACT II compliance, such as condensate collection and Clean-Condensate-Alternatives (CCA)

  19. Bioconversion of oxygen-pretreated Kraft lignin to microbial lipid with oleaginous Rhodococcus opacus DSM 1069

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Zhen [Hunan Univ. Changsha (China); Zeng, Guangming [Hunan Univ. Changsha (China); Huang, Fang [Georgia Inst. of Technology, Atlanta, GA (United States); Kosa, Matyas [Georgia Inst. of Technology, Atlanta, GA (United States); Huang, Danlian [Hunan Univ. Changsha (China); Ragauskas, Arthur J. [Georgia Inst. of Technology, Atlanta, GA (United States); Univ. of Tennessee, Knoxville, TN (United States)

    2015-04-09

    Kraft lignin (KL) from black liquor is an abundantly available, inexpensive aromatic resource that is regarded as a low value compound by the pulp and paper industry, necessitating the development of new applications.

  20. Kraft kasvatab Nordea haaret Eestis / Vahur Kraft

    Index Scriptorium Estoniae

    Kraft, Vahur, 1961-

    2006-01-01

    Avades lähikuudel seitse uut harukontorit, toimub Nordea Panga juhatuse esimehe Vahur Krafti juhtimisel suurim laienemine ettevõtte ajaloos. Ühtlasi peab Kraft jätkuvalt oluliseks internetipanga ja teiste elektrooniliste teenuste arendamist

  1. Effects of Non Process Elements in the chemical recovery system of a kraft pulp mill from the incineration in the recovery boiler of biological sludge; Effekter av PFG vid indunstning och foerbraenning av bioslam i ett massabruks sodapanna

    Energy Technology Data Exchange (ETDEWEB)

    Dahlbom, Johan

    2003-01-01

    The purpose of this project was to investigate the effects of incineration of biological sludge in the recovery boiler of a Swedish Kraft pulp mill, StoraEnso Pulp AB Skutskaers Bruk, which has practiced incineration of sludge in the recovery boiler during the last two years. The following aspects of the technique were investigated: Experience from operation of incineration of biological sludge in the recovery boiler; The content of Non-Process Elements (NPE) in process flows and evaluate the risks of incrustations in the system; The build-up of NPE in the chemicals recovery system and the estimated increase in make-up lime demand; and Technical risks for mills with different process equipment. This study comprises the following NPE: aluminium, silicon, phosphorus, magnesium, calcium, chloride, iron, manganese, potassium, copper, and nitrogen. The operational experience from the system for hydrolysis of the biological sludge and evaporation/incineration in the recovery boiler is excellent. The handling of the sludge takes place in a closed system that demands little supervision and maintenance. Overall, the mill has not seen any negative effects that can be explained by increased intake of NPEs to the chemical recovery system. Aluminium can lead to troublesome incrustations of sodium-aluminium-silicates on the heat surfaces in the evaporation plant. An effective elimination of aluminium by the green liquor dreg is obtained with the double salt hydrotalcite if the quotient Mg/Al is kept higher than 4-5 in the black liquor. The need for make-up lime has increased due to the build-up of phosphorus in the lime. Depending on the level of make-up lime the need will increase 2-5 kg/ t{sub 90} at a price of 2-5 kr/t{sub 90}. If a higher level of phosphorus is accepted instead of increasing lime make-up the running costs will be somewhat higher, 0,5-1 kr/t{sub 90} due to increased ballast. NO{sub x} in the flue gases from the recovery boiler has not increased since the

  2. Comparative study of percentage yield of pulp from various Nigerian ...

    African Journals Online (AJOL)

    user

    lignin content and lignin type present in these wood species. The infra red analysis of the pulp obtained from the various wood species confirmed the chemical integrity of the pulps obtained from all the hard wood species surveyed. Key words: Kraft pulp, Nigerian wood species, pulp yield, cellulose. INTRODUCTION.

  3. Understanding and adding value to Eucalyptus fibre | Clarke ...

    African Journals Online (AJOL)

    Eucalyptus wood has become one of the most important hardwood resources for pulp mills worldwide. Furthermore, bleached Eucalyptus pulp is used extensively both in paper-making globally where it is included in such diverse products as tissue, packaging, as well as printing papers and in chemical cellulose products ...

  4. Biochemical methane potential of kraft bleaching effluent and codigestion with other in-mill streams

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Dahl, Olli; Master, Emma

    2016-01-01

    A biochemical methane potential assay was conducted to investigate the anaerobic digestibility of bleaching effluent from hardwood kraft pulping and the potential of codigestion with other effluents from an integrated pulp and paper mill. Four in-mill streams were tested individually and in combi......A biochemical methane potential assay was conducted to investigate the anaerobic digestibility of bleaching effluent from hardwood kraft pulping and the potential of codigestion with other effluents from an integrated pulp and paper mill. Four in-mill streams were tested individually...... of anaerobic inhibitors such as adsorbable organic halogens (36 mg/L), total sulfur (170 mg/L), and resin and fatty acids (3.2 mg/L). Therefore, the total bleaching effluent from hardwood kraft pulping may be considered for full-scale anaerobic wastewater treatment, either as a singular stream or as part...... of a composite stream including other in-mill effluents....

  5. Genomic research in Eucalyptus.

    Science.gov (United States)

    Poke, Fiona S; Vaillancourt, René E; Potts, Brad M; Reid, James B

    2005-09-01

    Eucalyptus L'Hérit. is a genus comprised of more than 700 species that is of vital importance ecologically to Australia and to the forestry industry world-wide, being grown in plantations for the production of solid wood products as well as pulp for paper. With the sequencing of the genomes of Arabidopsis thaliana and Oryza sativa and the recent completion of the first tree genome sequence, Populus trichocarpa, attention has turned to the current status of genomic research in Eucalyptus. For several eucalypt species, large segregating families have been established, high-resolution genetic maps constructed and large EST databases generated. Collaborative efforts have been initiated for the integration of diverse genomic projects and will provide the framework for future research including exploiting the sequence of the entire eucalypt genome which is currently being sequenced. This review summarises the current position of genomic research in Eucalyptus and discusses the direction of future research.

  6. STUDIES ON HIBISCUS CANNABINUS, HIBISCUS SABDARIFFA, AND CANNABINUS SATIVA PULP TO BE A SUBSTITUTE FOR SOFTWOOD PULP- PART 1: AS-AQ DELIGNIFICATION PROCESS

    OpenAIRE

    Dharm Dutt; J. S. Upadhyaya; C. H. Tyagi

    2010-01-01

    Hibiscus cannabinus, Hibiscus sabdariffa, and Cannabinus sativa, which are renewable non-woody fiber resources having characteristics similar to that of softwood (bast fibers), when used together with hardwood (core fibers), gave higher pulp yield with good mechanical strength properties when using an alkaline sulphite-anthraquinone (AS-AQ) pulping process rather than a conventional kraft pulping process and bleached more readily than kraft and soda pulps with a CEHH bleaching sequence. A com...

  7. Kraft cooking of gamma irradiated wood, (2)

    International Nuclear Information System (INIS)

    Inaba, Masamitsu; Meshitsuka, Gyosuke; Ishizu, Atsushi; Nakano, Junzo

    1981-01-01

    Pre-irradiation of wood in alkaline aqueous ethanol increases kraft pulp yield by up to 1.2%, as already reported. In order to clarify the mechanism of the pulp yield gain, the behaviors of lignin and carbohydrates during pre-irradiation and cooking were investigated. The results are summarized as follows: 1) γ-Irradiation of guaiacylethane in alkaline aqueous ethanol produced 5-(1-hydroxyethyl)-guaicylethane, which is formed by radical coupling between α-hydroxyethyl radical from ethanol and guaiacylethane radical having an unpaired electron at C-5. 5,5'-Dehydrodiguaiacylethane, which may be a predominant product produced by γ-irradiation in the absence of ethanol, was also detected. 2) The yield of vanillin obtained by nitrobenzene oxidation of MWL decreased with an increase of γ-ray dosage. The presence of ethanol during γ-irradiation lessened the extent of this decrease and also the degradation of cellobiose. 3) Gel filtration of the products obtained by γ-irradiation of MWL and cellobiose in the presence of 14 C-ethanol showed the possible combination between ethanol and MWL or cellobiose. 4) Molecular weight distributions of kraft lignin obtained from pre-irradiated beech chips were compared with those obtained from unirradiated chips. This result shows that γ-irradiation in the presence of ethanol decreases the ability of lignin to condense during kraft cooking. (author)

  8. Clones de Eucalyptus versus a produção de polpa celulósica

    Directory of Open Access Journals (Sweden)

    Paulo Fernando Trugilho

    2005-01-01

    Full Text Available The wood quality is defined by combining several intrinsic characteristics of the tree to its use. This research aimed to evaluate some of the wood characteristics of Eucalyptus clones and its performance in kraft pulping. Fifteen clones, 5.8 years-old were used, two trees from each clone, totaling thirty trees. The evaluated wood characteristics were: basic density, fiber dimensions (fiber length, wall thickness, lumen diameter and chemical composition (cellulose, lignin, hemicelluloses, extractives and ash contents. Four samples were cooked at the laboratory for each tree, using different active alkali, to establish the delignification curve. These alkali loads were selected after exploratory cooking to obtain an eighteen kappa number at the medium point of the curve. In the cooking were appraised the screened, the pulp viscosity and consumed alkali. The yield results varied from 43.4 to 52.0%, the active alkali from 17.5 to 23.4%, the consumed alkali from 15.5 to 20.0% and the pulp viscosity from 19.9 to 61.4 cP.

  9. Effect of Urea Addition on Soda Pulping of Oak Wood

    OpenAIRE

    Cho, Nam-Seok; Matsumoto, Yuji; Cho, Hee-Yeon; Shin, Soo-Jeong; Oga, Shoji

    2008-01-01

    Many studies have been conducted to find a sulfur-free additive for alkaline pulping liquors that would have an effect similar to that of sulfide in kraft pulping. Some reagents that partially fulfill this role have been found, but they are too expensive to be used in the quantities required to make them effective. As an alternative method to solve air pollution problem and difficulty of pulp bleaching of kraft pulping process, NaOH-Urea pulping was applied. The properties of NaOH-Urea pul...

  10. Comparative study of percentage yield of pulp from various Nigerian ...

    African Journals Online (AJOL)

    Comparative study of percentage yield of pulp from various Nigerian wood species using the kraft process. ... African Journal of Environmental Science and Technology ... The infra red analysis of the pulp obtained from the various wood species confirmed the chemical integrity of the pulps obtained from all the hard wood ...

  11. Properties of kenaf from various cultivars, growth and pulping conditions

    Science.gov (United States)

    James S. Han; Ernest S. Miyashita; Sara J. Spielvogel

    1999-01-01

    The physical properties of kenaf offer potential as an alternative raw material for the manufacture of paper. Investigations to date have not determined whether core and fiber should be pulped together or separately. Kenaf bast and core fibers of different cultivars were pulped under various kraft pulping conditions and physical properties: density, Canadian Standard...

  12. Simultaneous and rapid determination of multiple component concentrations in a Kraft liquor process stream

    Science.gov (United States)

    Li, Jian [Marietta, GA; Chai, Xin Sheng [Atlanta, GA; Zhu, Junyoung [Marietta, GA

    2008-06-24

    The present invention is a rapid method of determining the concentration of the major components in a chemical stream. The present invention is also a simple, low cost, device of determining the in-situ concentration of the major components in a chemical stream. In particular, the present invention provides a useful method for simultaneously determining the concentrations of sodium hydroxide, sodium sulfide and sodium carbonate in aqueous kraft pulping liquors through use of an attenuated total reflectance (ATR) tunnel flow cell or optical probe capable of producing a ultraviolet absorbency spectrum over a wavelength of 190 to 300 nm. In addition, the present invention eliminates the need for manual sampling and dilution previously required to generate analyzable samples. The inventive method can be used in Kraft pulping operations to control white liquor causticizing efficiency, sulfate reduction efficiency in green liquor, oxidation efficiency for oxidized white liquor and the active and effective alkali charge to kraft pulping operations.

  13. The effect of wood supply and bleaching process on pulp brightness stability O efeito do tipo de madeira e do processo de branqueamento na estabilidade da alvura da polpa

    Directory of Open Access Journals (Sweden)

    Romildo Lopes Oliveira

    2006-06-01

    Full Text Available One hundred different 5.5-year-old Eucalyptus grandis x Eucalyptus urophylla wood clones were cooked to kappa number 15-17.5 and the resulting kraft pulps oxygen-delignified to kappa 9.5-11.5 under fixed conditions, except for chemical charges. Thirteen samples showing large variations in effective alkali requirement, pulp yield and O-stage efficiency and selectivity were selected for brightness reversion studies. These samples were bleached to 90-91% ISO by DEDD and DEDP sequences and their brightness stability and chemical characteristics determined. Heat reversion of the eucalyptus kraft pulps was strongly influenced by the wood supply, with brightness loss varying in the range of 2.1-3.6 and 0.8-1.7 %ISO for ODEDD and ODEDP bleached pulps, respectively. Pulps bleached by the ODEDP sequence showed reversion values 1.3-1.9 % ISO lower than those bleached by the ODEDD sequence. Pulp carbonyl content decreased by 35-40% during the final peroxide bleaching stage. Carbonyl and carboxyl groups correlated positively with brightness reversion, as did permanganate number and acid soluble lignin. Pulp final viscosity and metal and DCM extractives contents showed no significant correlation with brightness reversion. Pulping, oxygen delignification and ECF bleaching performances also showed no correlation with brightness reversion.Madeiras de 100 diferentes clones de Eucalyptus grandis e Eucalyptus urophylla, com aproximadamente 5,5 anos de idade, foram cozidas ao número kappa 15-17,5. As polpas kraft produzidas foram pré-deslignificadas com oxigênio ao número kappa 9,5-11,5, sob condições fixas. Treze polpas, que mostraram grandes variações na exigência da carga de álcali efetivo e rendimento no processo de polpação, seletividade e eficiência no estágio de Pré-O, foram selecionadas e branqueadas à alvura DE 90-91% ISO pelas seqüências DEDD e DEDP, para estudos de estabilidade de alvura e características químicas. A reversão de

  14. Regeneration and transformation of Eucalyptus grandis

    OpenAIRE

    Esteki, Leila

    2013-01-01

    Dissertação de mestrado em Biologia Molecular, Biotecnologia e Bioempreendedorismo em Plantas Eucalyptus grandis is the most widely used species in planted forests in tropical and subtropical areas. The traits of interest underlying Eucalyptus breeding programs concern productivity and wood quality for the pulp and paper industry, as well as biotic and abiotic stress tolerance. The development of an efficient transformation protocol is necessary to explore eucalypt resources th...

  15. Evaluating pulp stiffness from fibre bundles by ultrasound

    Science.gov (United States)

    Karppinen, Timo; Montonen, Risto; Määttänen, Marjo; Ekman, Axel; Myllys, Markko; Timonen, Jussi; Hæggström, Edward

    2012-06-01

    A non-destructive ultrasonic tester was developed to measure the stiffness of pulp bundles. The mechanical properties of pulp are important when estimating the behaviour of paper under stress. Currently available pulp tests are tedious and alter the fibres structurally and mechanically. The developed tester employs (933 ± 15) kHz tweezer-like ultrasonic transducers and time-of-flight measurement through (9.0 ± 2.5) mm long and (0.8 ± 0.1) mm thick fibre bundles kept at (19.1 ± 0.4) °C and (62 ± 1)% RH. We determined the stiffness of soft wood pulps produced by three kraft pulping modifications: standard kraft pulp, (5.2 ± 0.4) GPa, prehydrolysis kraft pulp, (4.3 ± 0.4) GPa, and alkali extracted prehydrolysis kraft pulp, (3.3 ± 0.4) GPa. Prehydrolysis and alkali extraction processes mainly lowered the hemicellulose content of the pulps, which essentially decreased the fibre-wall stiffness hence impairing the stiffness of the fibre networks. Our results indicate that the method allows ranking of pulps according to their stiffness determined from bundle-like samples taken at an early phase of the papermaking process.

  16. Understanding the Nature and Reactivity of Residual Lignin for Improved Pulping and Bleaching Efficiency; FINAL

    International Nuclear Information System (INIS)

    Yuan-Zong Lai

    2001-01-01

    One of the most formidable challenges in kraft pulping to produce bleached chemical pulps is how to effectively remove the last 5-10% of lignin while maintaining the fiber quality. To avoid a severe fiber degradation, kraft pulping is usually terminated in the 25-30 kappa number range and then followed by an elementally chlorine free (ECF) or a totally chlorine free (TCF) bleaching sequence to reduce the environmental impacts

  17. Understanding the Nature and Reactivity of Residual Lignin for Improved Pulping and Bleaching Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Yuan-Zong Lai

    2001-11-30

    One of the most formidable challenges in kraft pulping to produce bleached chemical pulps is how to effectively remove the last 5-10% of lignin while maintaining the fiber quality. To avoid a severe fiber degradation, kraft pulping is usually terminated in the 25-30 kappa number range and then followed by an elementally chlorine free (ECF) or a totally chlorine free (TCF) bleaching sequence to reduce the environmental impacts.

  18. Arundo donax L. reed: new perspectives for pulping and bleaching. Part 4. Peroxide bleaching of organosolv pulps.

    Science.gov (United States)

    Shatalov, A A; Pereira, H

    2005-05-01

    A comparative study on TCF (totally chlorine-free) bleachability of organosolv pulps from the annual fibre crop Arundo donax L. (giant reed) was carried out using a simple three-stage peroxide bleaching sequence without oxygen pre-bleaching. ASAM (alkali-sulfite-anthraquinone-methanol), Organocell (alkali-anthraquinone-methanol) and ethanol-soda organosolv pulps were bleached and compared with kraft pulp, as a reference. The final brightness of 76-78% ISO was attained for all tested pulps. The chemical charge required to reach this level of brightness varied for different pulps (despite the equal initial content of the residual lignin) and directly related to starting brightness values. No direct correlation between brightness improvement and lignin removal during bleaching was found, indicating the influence of the specific pulp properties introduced by pulping process on bleaching chemistry. The general higher bleaching response of organosolv pulps from A. donax was noted in comparison with kraft.

  19. Soil attributes and wood quality for pulp production in plantations of Eucalyptus grandis clone Atributos do solo e qualidade da madeira para produção de celulose em plantações clonais de Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    José Luiz Gava

    2008-01-01

    Full Text Available The soil attributes can affect the wood quality of eucalypt, which may result in considerable effect on cellulose production. This study evaluated the effect of different physical and chemical soil attributes on wood quality of Eucalyptus grandis for cellulose production. Five sites were selected at the Western Plateau of the State of São Paulo, planted with one clone of Eucalyptus grandis, with ages ranging between 6.5 and 7.0 years. Four soil types, with texture ranging from sandy to very clayey were found. At each site, three experimental plots were allocated with 100 trees each. Trees representative of each class frequency of diameter at breast height were harvested. Their biomass and wood components were characterized. The wood productivity and quality was affected by physical attributes of soil, mainly clay content, which is directly related to the amount of available water. Basic wood density did not changed at different soil types. Total lignin content decreased and holocellulose content exponentially increased as soil clay content increased (until about 350 to 400 g kg-1 of clay. The wood extractives content was not affected by soil attributes. Screened cellulose yield exponentially increased with soil clay content.Os atributos edáficos podem afetar a qualidade da madeira de eucalipto, o que pode resultar em considerável efeito sobre a produção de celulose. Este trabalho teve como objetivo avaliar o efeito de atributos físicos e químicos do solo na qualidade da madeira de Eucalyptus grandis usada para polpação celulósica. Foram selecionadas cinco áreas no planalto ocidental do Estado de São Paulo, Brasil, plantadas com um mesmo clone de Eucalyptus grandis, com idades variando entre 6,5 e 7,0 anos de idade. Quatro classes de solo, com textura arenosa a muito argilosa, foram encontradas. Em cada uma das cinco áreas, foram demarcadas, aleatoriamente, 3 parcelas com 100 plantas cada. Em cada parcela, foram colhidas

  20. Effect of type of fungal culture, type of pellets and pH on the semi-continuous post-treatment of an anaerobically-pretreated weak black liquor from kraft pulp industry

    International Nuclear Information System (INIS)

    Robledo-Narvaez, P. N.; Ortega-Clemente, L. A.; Ponce-Noyola, M. T.; Rinderknecht-Seijas, N. F.; Poggi-Varaldo, H. M.

    2009-01-01

    It is well known that fungi belonging to the Basidiomycetes (such as Trametes versicolor, Lentinus edodes, Phanerochaete chrysosporium) are microorganisms with a demonstrated capability of degrading lignin and its derivatives using a powerful and diverse group of enzymes. Because of these features, ligninolytic fungi have been used for the treatment or post-treatment of a variety of recalcitrant and toxic effluents, those of the Kraft industry among them. Yet, most of reported fungal treatments so far required the supplementation with glucose or other soluble carbohydrates, pH 4 to 4,5, and their effective performance was demonstrated only for short periods of operation time. (Author)

  1. Effect of type of fungal culture, type of pellets and pH on the semi-continuous post-treatment of an anaerobically-pretreated weak black liquor from kraft pulp industry

    Energy Technology Data Exchange (ETDEWEB)

    Robledo-Narvaez, P. N.; Ortega-Clemente, L. A.; Ponce-Noyola, M. T.; Rinderknecht-Seijas, N. F.; Poggi-Varaldo, H. M.

    2009-07-01

    It is well known that fungi belonging to the Basidiomycetes (such as Trametes versicolor, Lentinus edodes, Phanerochaete chrysosporium) are microorganisms with a demonstrated capability of degrading lignin and its derivatives using a powerful and diverse group of enzymes. Because of these features, ligninolytic fungi have been used for the treatment or post-treatment of a variety of recalcitrant and toxic effluents, those of the Kraft industry among them. Yet, most of reported fungal treatments so far required the supplementation with glucose or other soluble carbohydrates, pH 4 to 4,5, and their effective performance was demonstrated only for short periods of operation time. (Author)

  2. Rescue of syringyl lignin and sinapate ester biosynthesis in Arabidopsis thaliana by a coniferaldehyde 5-hydroxylase from Eucalyptus globulus.

    Science.gov (United States)

    García, José Renán; Anderson, Nickolas; Le-Feuvre, Regis; Iturra, Carolina; Elissetche, Juan; Chapple, Clint; Valenzuela, Sofía

    2014-08-01

    The gene coding for F5H from Eucalyptus globulus was cloned and used to transform an f5h -mutant of Arabidopsis thaliana , which was complemented, thus verifying the identity of the cloned gene. Coniferaldehyde 5-hydroxylase (F5H; EC 1.14.13) is a cytochrome P450-dependent monooxygenase that catalyzes the 5-hydroxylation step required for the production of syringyl units in lignin biosynthesis. The Eucalyptus globulus enzyme was characterized in vitro, and results showed that the preferred substrates were coniferaldehyde and coniferyl alcohol. Complementation experiments demonstrated that both cDNA and genomic constructs derived from F5H from E. globulus under the control of the cinnamate 4-hydroxylase promoter from Arabidopsis thaliana, or a partial F5H promoter from E. globulus, can rescue the inability of the A. thaliana fah1-2 mutant to accumulate sinapate esters and syringyl lignin. E. globulus is a species widely used to obtain products that require lignin removal, and the results suggest that EglF5H is a good candidate for engineering efforts aimed at increasing the lignin syringyl unit content, either for kraft pulping or biofuel production.

  3. Positive and negative aspects of soda/anthraquinone pulping of hardwoods.

    Science.gov (United States)

    Francis, R C; Bolton, T S; Abdoulmoumine, N; Lavrykova, N; Bose, S K

    2008-11-01

    The positive aspects of the non-sulfur soda/anthraquinone (SAQ) process are mostly tied to improved energy efficiency while lower pulp brightness after bleaching is its most significant drawback. A credible method that quantifies bleachability as well as an approach that solves the problem for SAQ pulps from hardwoods will be described. A straight line correlation (R2=0.904) was obtained between O2 kappa number and final light absorption coefficient (LAC) value after standardized OD0EpD1 bleaching of nine hardwood kraft pulps from three laboratories and one pulp mill. The bleachability of pulps from four different soda processes catalyzed by anthraquinone (AQ) and 2-methylanthraquinone (MAQ) was compared to that of conventional kraft pulps by comparing O2 kappa number decrease and final LAC values. It was observed that a mild hot water pre-hydrolysis improved the bleachability of SAQ pulps to a level equal to that of kraft.

  4. Pengaruh Media Dan Tempat Tumbuh Terhadap Pertumbuhan Anakan Eucalyptus Urophylla Dan Eucalyptus Pellita

    OpenAIRE

    Komarayati, Sri; Gusmailina, Gusmailina

    2010-01-01

    Tulisan ini menyajikan hasil penelitian penggunaan pupuk organik dan pupuk organik mikoriza dari sludge industri pulp pada dua jenis anakan Ekaliptus selama lima bulan di Rumah Kaca. Tujuan penelitian adalah untuk mengetahui pengaruh penambahan pupuk organik, tablet pupuk organik mikoriza dan tempat sapih terhadap pertumbuhan anakan Eucalyptus urophylla dan Eucalyptus pellita.Hasil penelitian menunjukkan bahwa tempat sapih berupapolybag memberikan pengaruh yang terbaik terhadap pertumbuhan ta...

  5. RNA-Seq using two populations reveals genes and alleles controlling wood traits and growth in Eucalyptus nitens.

    Directory of Open Access Journals (Sweden)

    Saravanan Thavamanikumar

    Full Text Available Eucalyptus nitens is a perennial forest tree species grown mainly for kraft pulp production in many parts of the world. Kraft pulp yield (KPY is a key determinant of plantation profitability and increasing the KPY of trees grown in plantations is a major breeding objective. To speed up the breeding process, molecular markers that can predict KPY are desirable. To achieve this goal, we carried out RNA-Seq studies on trees at extremes of KPY in two different trials to identify genes and alleles whose expression correlated with KPY. KPY is positively correlated with growth measured as diameter at breast height (DBH in both trials. In total, six RNA bulks from two treatments were sequenced on an Illumina HiSeq platform. At 5% false discovery rate level, 3953 transcripts showed differential expression in the same direction in both trials; 2551 (65% were down-regulated and 1402 (35% were up-regulated in low KPY samples. The genes up-regulated in low KPY trees were largely involved in biotic and abiotic stress response reflecting the low growth among low KPY trees. Genes down-regulated in low KPY trees mainly belonged to gene categories involved in wood formation and growth. Differential allelic expression was observed in 2103 SNPs (in 1068 genes and of these 640 SNPs (30% occurred in 313 unique genes that were also differentially expressed. These SNPs may represent the cis-acting regulatory variants that influence total gene expression. In addition we also identified 196 genes which had Ka/Ks ratios greater than 1.5, suggesting that these genes are under positive selection. Candidate genes and alleles identified in this study will provide a valuable resource for future association studies aimed at identifying molecular markers for KPY and growth.

  6. Electrochemical delignification of wood pulp using polyoxometalate mediators

    Science.gov (United States)

    R.S. Reiner; E.L. Springer; R.H. Atalla

    2003-01-01

    It has been found that polyoxometalates (POMs) can act as mediators in the electrochemical oxidation of lignin in pulps. An electrochemical cell, with a Nafion® membrane separating the anode and cathode compartments, was used in the delignification experiments. A softwood kraft pulp was placed in the anode compartment with a buffered 0.01M solution of the...

  7. Bambu como matéria-prima para papel: IV - Estudos sôbre o emprêgo de cinco espécies de Bambusa,na produção de celulose sulfato Bamboo as a raw material for the pulp and paper industry: IV - Study of Bambusa tuldoides, B. textilis, B. ventricosa, B. malingensis and B. dissimulator in the production of kraft pulp

    Directory of Open Access Journals (Sweden)

    Anísio Azzini

    1971-05-01

    Full Text Available Com o presente trabalho, os autores dão continuidade aos estudos com que se procura determinar as características papeleiras das principais espécies de bambu com bom desenvolvimento nas condições ecológicas do Estado de São Paulo. Bambusa tuldoides, B. textilis, B. ventricosa, B. malingensis e B. dissimulator foram estudadas levando-se em consideração as seguintes variáveis: dimensões dos colmos, densidade básica, análise micrométrica das fibras, rendimento em celulose sulfato (Kraft e características físico-mecânicas das pastas produzidas. As densidades básicas médias calculadas para as espécies em estudo não apresentaram muita variação, com valores extremos de 0,62 e 0,78. Relativamente ao comprimento médio das fibras, as espécies de bambu estudadas mostraram ocupar uma posição intermediária entre as resinosas e as principais espécies arbóreas folhosas utilizadas pela indústria de papel. Os rendimentos médios em celulose sulfato, considerando cinco repetições, foram de 43,75% para B. textilis, 42,53% para B. tuldoides, 41,74% para B. ventricosa, 36,57% para B. dissimulator e 35,82% para B. malingensis, com número de permanganato variando de 18,37 a 17,03. Análise estatística dos dados de resistência do papel demonstrou que B. dissimulator, com exceção do índice de rasgo, apresentou maiores valores que as demais espécies em estudo.Five bamboo species, very similar in the agronomic features, were studied in the production of kraft pulp. All of them have culms with about 9 m in height, 4-5 cm in diameter and weight of 4-5 kg, growing very well in the soil and climate conditions of São Paulo State. Determinations of the basic density of culms and dimension of fibres were made. Chips were obtained mechanically and the cookings were made by the sulfate process at 160°C for l hour, using 14% Na(20 and 25% sul-phidity. Bambusa textilis and B. tuldoides which yielded, respectively 43.75% and 42.53% of

  8. A comprehensive program to develop correlations for physical properties of kraft black liquor. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, A.L.; Zaman, A.A.

    1998-05-01

    The overall objective of the program was to develop correlations to predict physical properties within requirements of engineering precision from a knowledge of pulping conditions and of kraft black liquor composition, if possible. These correlations were to include those relating thermodynamic properties to pulping conditions and liquor composition. The basic premise upon which the research was based is the premise that black liquor behaves as a polymer solution. This premise has proven to be true, and has been used successfully in developing data reduction methods and in interpreting results. A three phase effort involving pulping, analysis of liquor composition, and measurement of liquor properties was conducted.

  9. The Fractionation of Loblolly Pine Woodchips Into Pulp For Making Paper Products

    Energy Technology Data Exchange (ETDEWEB)

    Kiran Kadam, PhD

    2006-11-30

    The overall goal of the project was to test the PureVision biomass fractionation technology for making pulp from loblolly pine. A specific goal was to produce a pulp product that is comparable to pulp produced from the kraft process, while reducing the environmental effects of the kraft process, known to be a highly pollutant process. The overall goal of the project was met by using the biomass fractionation concept for making pulp product. This proof-of-concept study, done with Southern pine pinchips as feedstock, evaluated NaOH concentration and residence time as variables in single-stage cocurrent pulping process. It can be concluded that 1% NaOH is adequate for effective delignification using the PureVision process; this is about 1/3 of that used in the kraft process. Also, the PureVision process does not use sulfur-based chemicals such as N2S and hence, is environmentally more benign.

  10. Genetic transformation of Eucalyptus camaldulensis by agrobalistic method

    OpenAIRE

    Evânia Galvão Mendonça; Vanessa Cristina Stein; Flávia Pereira Balieiro; Carolina Delfin Fernandes Lima; Breno Régis Santos; Luciano Vilela Paiva

    2013-01-01

    Eucalyptus stands in the setting of worldwide forestry due to its adaptability, rapid growth, production of high-quality and low cost of wood pulp fibers. The eucalyptus convetional breeding is impaired mainlly by the long life cycle making the genetic transformation systems an important tool for this purpose. However, this system requires in vitro eficient protocols for plant induction, regeneration and seletion, that allow to obtain transgenic plants from the transformed cell groups. The ai...

  11. Investigation of pulping and paper making potential of weeds

    Directory of Open Access Journals (Sweden)

    omid Ghaffarzadeh Mollabashi

    2017-08-01

    Full Text Available Increasing use of wood products accompanying with resource constraint has revealed the importance of nonwood based material. In this study, pulping and papermaking potential of three varieties of weeds including Xanthium spinosum, Carthamus tinctorius and Cyperus papyrus have been considered. At first, chemical components of the samples i.e. cellulose, lignin and extractives have been measured following TAPPI standard test methods. Afterwards, pulping process based as soda and Kraft has been carried out and the pulp properties i.e. screen yield and reject, kappa number, caliper, bust index, tear index, brightness have been considered. According to the results, the amount cellulose, lignin and extractives have been measured for the Xanthium spinosum %38.15, %13.5 and 4.72, respectively. Theses parameters have been estimated about %38.25, %10.3 and % 2.95 for Carthamus tinctorius and %38.8, %19.2 and 4.4 in case of papyrus. The yield of soda and Kraft pulp of the papyrus was more than Xanthium spinosum and Carthamus tinctorius. Among all treatments, the highest screen yield related to soda pulping of Cyperus papyrus by %39.8 which has been obtained by 175 centigrade as a maximum temperature, L/W: 6/1, active alkaline: %30 and 90 minutes as the time at temperature. The lowest and highest amounts of the tear index were related to soda pulp sample of the Carthamus tinctorius and Kraft pulp sample of Xanthium spinosum by 2.49 and 8.1, respectively. In addition, the lowest and highest amounts of the bursting index were related to soda pulp sample of the Cyperus papyrus and Kraft pulp sample of Xanthium spinosum by 0.61and 2.48, respectively. Meanwhile, soda pulp sample of the Cyperus papyrus showed the highest amount of brightness with %45 ISO.

  12. Phylogenetic reassessment of Mycosphaerella spp. and their anamorphs occurring on Eucalyptus

    NARCIS (Netherlands)

    Crous, P.W.; Groenewald, J.Z.; Mansilla, J.P.; Hunter, G.C.; Wingfield, M.J.

    2004-01-01

    Species of Eucalyptus, mostly native to Australia, are widely planted as exotics in the tropics and Southern Hemisphere. These plantations represent an important source of fuel-wood, structural timber and pulp. Eucalyptus plantations are, however, vulnerable to infection by pathogens, including

  13. MASCULINIZATION OF FEMALE MOSQUITOFISH IN KRAFT MILL EFFLUENT-CONTAMINATED FENHOLLOWAY RIVER WATER IS ASSOCIATED WITH ANDROGEN RECEPTOR AGONIST ACTIVITY

    Science.gov (United States)

    Female mosquitofish (Gambusia affinis holbrooki) downstream from Kraft paper mills in Florida display masculinization of the anal fin, an androgen-dependent trait. The current investigation was designed to determine if water contaminated with pulp mill effluent (PME) from the Fe...

  14. Vahur Kraft soovitab elektritootmise erastada / Vahur Kraft ; interv. Vallo Toomet

    Index Scriptorium Estoniae

    Kraft, Vahur, 1961-

    2003-01-01

    Eesti Panga president Vahur Kraft soovitab seoses Iraagi sõja ja ebakindlusega maailmas suhtuda ettevaatlikult majanduskasvu prognoosi ning näeb maksureformi läbiviimiseks vajaliku kokkuhoiu võimalusi hariduse, tervishoiu ja sotsiaalkindlustuse reformimisel. Diagramm. Tabel. Vt. samas: Andrus Säälik. Tulude alla jõuavad ka toetused

  15. Pulp and paper from blue agave waste from tequila production.

    Science.gov (United States)

    Idarraga, G; Ramos, J; Zuñiga, V; Sahin, T; Young, R A

    1999-10-01

    Pulping of blue agave waste, from the production of tequila, was evaluated by both chemical and biomechanical pulping processes. Two conventional and two organosolv systems were used to pulp the agave waste under a standard set of conditions. The soda-ethanol process was superior in terms of delignification and pulp properties in comparison to the soda and ethanol organosolv processes for pulping of agave waste; however, the kraft process gave the best strength properties. In general, the strength of the agave waste pulps was rather poor in comparison to wood and other agro-based pulps; however, the tear strength was relatively high. This result is typical of poorly bonded sheets and may be due to the coarseness of the agave fibers and/or loss of hemicelluloses in the steaming process for the tequila production. Fungal treatment of the agave waste with Ceriporiopsis subvermispora reduced the energy consumption for mechanical refining but gave biomechanical pulps with inferior strength properties. The blue agave chemical pulps should be suitable for blending with softwood kraft pulps for publication grade paper.

  16. Fluidization Characteristics of Medium-High-Consistency Pulp Fiber Suspensions with an Impeller

    Directory of Open Access Journals (Sweden)

    Ye Daoxing

    2016-01-01

    Full Text Available When the mass concentration exceeds 7%, pulp suspensions stop flowing and act like a solid. To investigate the fluidization characteristics of medium-high-consistency pulp suspensions and achieve pulp fluidization and pumping, experiments were carried out with waste tissue pulp and unbleached kraft pulp. The objectives of this paper were to study the rheology of medium-high-consistency pulp and to determine accurate parameters for the physical Herschel-Bulkley model. To validate this model, computational fluid dynamics (CFD results were compared to experimental data. The simulation values were very similar and were in agreement with experimental results.

  17. Enzyme processes for pulp and paper : a review of recent developments

    Science.gov (United States)

    William R. Kenealy; Thomas W. Jeffries

    2003-01-01

    The pulp and paper industry is applying new, ecologically sound technology in its manufacturing processes. Many interesting enzymatic applications have been proposed in the literature. Implemented technologies tend to change the existing industrial process as little as possible. Commercial applications include xylanases in prebleaching kraft pulps and various enzymes...

  18. Use of polymers and a surfactant in the treatment of Kraft process wastewater

    OpenAIRE

    Seyffert, Hans J.

    1988-01-01

    This study-investigated the use of cationic polymers, and a surfactant, EHDABr, in the color removal treatment of Kraft pulp and paper wastewater. Four polymers were evaluated for their color removal performance by jar test procedures. The polymers removed between 77 and 87% of the wastewater color. The affect of pH upon polymer performance varied with the polymer tested. Powdered activated carbon addition improved the performance of the polymers. The color removal abili...

  19. Novel Pulping Technology: Directed Green Liquor Utilization (D-GLU) Pulping

    Energy Technology Data Exchange (ETDEWEB)

    Lucian A. Lucia

    2005-11-15

    The general objectives of this new project are the same as those described in the original proposal. Conventional kraft pulping technologies will be modified for significant improvements in pulp production, such as strength, bleachability, and yield by using green liquor, a naturally high, kraft mill-derived sulfidity source. Although split white liquor sulfidity and other high sulfidity procedures have the promise of addressing several of the latter important economic needs of pulp mills, they require considerable engineering/capital retrofits, redesigned production methods, and thus add to overall mill expenditures. Green liquor use, however, possesses the required high sulfidity to obtain in general the benefits attributable to higher sulfidity cooking, without the required capital constraints for implementation. Before introduction of green liquor in our industrial operations, a stronger understanding of its fundamental chemical interaction with the lignin and carbohydrates in US hardwood and softwoods must be obtained. In addition, its effect on bleachability, enhancement of pulp properties, and influence on the overall energy and recovery of the mill requires further exploration before the process witnesses widespread mill use in North America. Thus, proof of principle will be accomplished in this work and the consequent effect of green liquor and other high sulfide sources on the pulping and bleaching operations will be explored for US kraft mills. The first year of this project will generate the pertinent information to validate its ability for implementation in US pulping operations, whereas year two will continue this work while proceeding to analyze pulp bleachability and final pulp/paper properties and develop a general economic and feasibility analysis for its eventual implementation in North America.

  20. Biochemical methane potential of kraft bleaching effluent and codigestion with other in-mill streams

    DEFF Research Database (Denmark)

    Fitamo, Temesgen Mathewos; Dahl, Olli; Master, Emma

    2016-01-01

    A biochemical methane potential assay was conducted to investigate the anaerobic digestibility of bleaching effluent from hardwood kraft pulping and the potential of codigestion with other effluents from an integrated pulp and paper mill. Four in-mill streams were tested individually...... degradation and methane generation. Chemical oxygen demand (COD) removal ranged from 57%-76%, and methane generation was 220-280 mL/g COD contained in the wastewater, depending on the degree of dilution. When codigestion was tested, the composite consisting of total bleaching effluent, chemithermomechanical...

  1. Research studies on tropical hardwoods for pulp and paper manufacture

    Energy Technology Data Exchange (ETDEWEB)

    Escolano, J.O.; Tamolang, F.N.

    1981-01-01

    Kraft cooking of hardwood mixtures containing combinations of Shorea polysperma, S. negrosensis, Pentocone contorta, S. squamata, Dipterocarpus grandifluorus, Anisoptera thurifera, S. blume, and Hopea acuminata at 170 degrees gave pulp in 48% yield, with permanganate No. 13.8, burst factor 70-80, tear factor 129-130, MIT double folds 475-700, and breaking length 8500-9800 m. Physiochemical and strength characteristics of tropical hardwoods and their pulps are also reviewed.

  2. Eucalyptus oil poisoning.

    OpenAIRE

    Patel, S; Wiggins, J

    1980-01-01

    Accidental ingestion of eucalyptus oil by a 3-year-old boy caused profound central nervous system depression within 30 minutes, but he recovered rapidly after gastric lavage. The extreme toxicity of eucalyptus oil is emphasised.

  3. Growth and yield models for Eucalyptus grandis grown in Swaziland ...

    African Journals Online (AJOL)

    The aim of this study was to develop a stand-level growth and yield model for short-rotationEucalyptus grandis grown for pulp wood production at Piggs Peak in Swaziland. The data were derived from a Nelder 1a spacing trial established with E. grandis clonal cuttings in 1998 and terminated in 2005. Planting density ...

  4. Cellulose pulp produced from bulrush fiber

    Directory of Open Access Journals (Sweden)

    Vania Karine Dick Wille

    Full Text Available ABSTRACT: Brazil continues to use wood as the principal raw material source for the pulp industry; although, non-wood fibers have been revealed to be a competent substitute to produce paper with different and exceptional properties. Keeping this in focus, this study aimed to assess potential of Schoenoplectus californicus fibers (C. A. Mey. Soják, commonly identified as bulrush or reed, in cellulosic pulp generation, as an alternative fiber source for the pulp and paper industry. On analyzing the chemical composition of reed fibers, extractives of lignin, carbohydrates, uronic acids and minerals were reported. Physico-chemical characteristics of reed-based cellulosic pulp were estimated including viscosity, hexenuronic acids, etc., as well as anatomical features of length, width, etc. From the chemical analyses of the reed the presence of high concentrations of extractives and silica was clear, making them unfit as raw material for cellulosic pulp production. Pulp kraft pulping process produced brown pulps low in viscosity (34.5m Pa.s and hexenuronic acid content. Reed is thus classifiable as short-fiber source for pulp and paper industries.

  5. Growth potential of Eucalyptus cypellocarpa as an alternative species for the mid-altitude summer rainfall region of South Africa

    CSIR Research Space (South Africa)

    Komakech, C

    2013-09-01

    Full Text Available Eucalyptus grandis is predominantly cultivated in the humid, warmer temperate, subtropical regions in South Africa for pulp and paper production because of its rapid growth and desirable wood properties. With forestry expanding into mid...

  6. Possible mechanism for anthraquinone species diffusion in alkaline pulping

    Science.gov (United States)

    X.-S. Chai; J. Samp; Q.X. Hou; S.-H Yoon; J.Y. Zhu

    2007-01-01

    An analysis of the effectiveness of anthraquinone (AQ) in kraft-AQ pulping in terms of its mechanism of transport has been conducted. Our previous work showed that caustic solutions of wood lignin can decrease the membrane exclusion for anthraquinones, i.e., the presence of wood lignin enhances the ability of AQ to pass through a membrane when a reducing agent is...

  7. Microscopic observations during longitudinal compression loading of single pulp fibers

    Science.gov (United States)

    Irving B. Sachs

    1986-01-01

    Paperboard components (linerboard adn corrugating medium) fail in edgewise compression because of failure of single fibers, as well as fiber-to-fiber bonds. While fiber-to-fiber-bond failure has been studied extensively, little is known about the longitudinal compression failure of a single fiber. In this study, surface alterations on single loblolly pine kraft pulp...

  8. Fungal demethylation of Kraft lignin.

    Science.gov (United States)

    Zou, Linyou; Ross, Brian M; Hutchison, Leonard J; Christopher, Lew P; Dekker, Robert F H; Malek, Lada

    2015-06-01

    Demethylation of industrial lignin has been for long coveted as a pathway to the production of an abundant natural substitute for fossil-oil derived phenol. In an attempt to possibly identify a novel Kraft lignin-demethylating enzyme, we surveyed a collection of fungi by using selected ion flow tube-mass spectrometry (SIFT-MS). This method readily identifies methanol resulting from lignin demethylation activity. Absidia cylindrospora, and unidentified Cylindrocladium sp. and Aspergillus sp. were shown to metabolize lignin via different pathways, based on the HPLC analysis of lignin fragments. Of these three, Cylindrocladium and Aspergillus were shown to retain most of the lignin intact after 3 weeks in culture, while removing about 40% of the available methoxy groups. Our results demonstrate that after optimization of culture and lignin recovery methods, biological modification of Kraft lignin may be a feasible pathway to obtaining demethylated lignin for further industrial use. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  9. Extended oxygen delignification of high kappa softwood pulp in a flow-through reactor

    OpenAIRE

    Jafari, Vahid

    2015-01-01

    Julkaistu vain painettuna, saatavuus katso Bibid. Published only in printed form, availability see Bibid Oxygen delignification (O-delignification) is an important tool for improving yield, reducing lignin content of pulp and lowering the bleach chemical consumption in the pulp and paper industries. This process is designed after cooking to maximize the delignification rate in comparison to the final phase of Kraft cooking without sacrificing pulp quality. In order to improve the yield of ...

  10. Evaluation of Seedlings Gowth of Eucalyptus badjensis in Substrata from Composted Residues (Pulp and Paper Mill, Brewery Industry and Goat Dung Resíduos Industriais e Dejetos da Caprinocultura como Componentes de Substratos para Produção de Mudas de Eucalyptus badjensis

    Directory of Open Access Journals (Sweden)

    Shizuo Maeda

    2011-03-01

    Full Text Available

    The aim of this work was to evaluate the seedling growth of Eucalyptus badjensis Beuzev. & Welch in substrata prepared from different residues: pulp and paper mill wastes (organic sludge and cellulose mill liquid alkaline liquor, brewery malt and also goat manure. The experiment was carried out in the seedlings nursery of the Embrapa Florestas, in Colombo, Paraná. The organic sludge, cellulose mill liquid alkaline liquor and the brewer’s grain were previously composted with sawdust, and goat dung with pinus bark. A randomized blocks design with split-plot arrangement, with four replications was used. Plot treatments were the substrata and split-plot were base fertilization (with and without: 1 mixture of a commercial substratum prepared with composted pinus bark in a volume/volume relation - v/v - of 1/1 - standard of the experiment when base fertilization was applied; 2 composted brewery malt with sawdust in a relation v/v of 1/4; 3 composted organic sludge with sawdust (relation v/v of 1/1; 4 mixture of
    treatment 3 with pinus bark (relation v/v of 1/1; 5 composted cellulose mill liquid alkaline waste with sawdust (relation v/v of 4/1; 6 composted cellulose mill liquid alkaline waste with sawdust (relation v/v of 3/2; 7 mixture of the product
    of treatment 6 with Pinus bark (relation v/v of 1/1; 8 composted goat dung with pinus bark. The results showed that substrata of treatments 2 and 8 can be used for the production of E. badjensis seedlings, with or without base fertilization, while treatment 4 can only be used with base fertilization. The growth of E. badjensis in the substratum of the standard treatment was not influenced by the lack of base fertilization.
    Com o objetivo de avaliar resíduos gerados nas produções de papel e celulose, de cerveja e na caprinocultura como substratos para a produção de mudas de Eucalyptus badjensis Beuzev. & Welch, foi

  11. 78 FR 31315 - Kraft Pulp Mills NSPS Review

    Science.gov (United States)

    2013-05-23

    ... lime kilns is PM with an aerodynamic diameter less than or equal to 2.5 micrometers (PM 2.5 ). The EPA... informational purposes. To increase the ease and efficiency of data submittal and improve data accessibility... to be removed with alkaline scrubbing, resulting in a removal efficiency much lower than that...

  12. Life cycle greenhouse gases and non-renewable energy benefits of kraft black liquor recovery

    International Nuclear Information System (INIS)

    Gaudreault, Caroline; Malmberg, Barry; Upton, Brad; Miner, Reid

    2012-01-01

    The life cycle greenhouse gas (GHG) and fossil fuel benefits of black liquor recovery are analyzed. These benefits are due to the production of energy that can be used in the pulping process or sold, and the recovery of the pulping chemicals that would otherwise need to be produced from other resources. The fossil GHG emissions and non-renewable energy consumption of using black liquor in the kraft recovery system are approximately 90% lower than those for a comparable fossil fuel-based system. Across all scenarios, the systems relying on black liquor solids achieve a median reduction of approximately 140 kg CO 2 eq./GJ of energy produced, compared to the systems relying on fossil fuels to provide the same energy and pulping chemical production functions. The benefits attributable to the recovery of pulping chemicals vary from 44% to 75% of the total benefit. Applied to the total production of kraft pulp in the U.S., the avoided emissions are equivalent to the total Scopes 1 and 2 emissions from the entire U.S. forest products industry. These results do not depend on the accounting method for biogenic carbon (because biogenic CO 2 emissions are the same for the systems compared) and the results are valid across a range of assumptions about the displaced fossil fuel, the GHG-intensity of the electricity grid, the fossil fuels used in the lime kiln, and the level of cogeneration at pulp and paper mills. The benefits occur without affecting the amount of wood harvested or the amount of chemical pulp produced. -- Highlights: ► Black liquor, a by-product of kraft pulping, represents about half of the energy used in the paper industry. ► The greenhouse gases (GHG) benefits of black liquor recovery compared to an equivalent fossil fuel system were analyzed. ► The GHG emissions of the black liquor system are approximately 90% lower than those for the fossil fuel system. ► The benefits from the recovery of the chemicals vary from 44% to 75% of the total benefit.

  13. Fiber length and pulping characteristics of switchgrass, alfalfa stems, hybrid poplar and willow biomasses.

    Science.gov (United States)

    Ai, Jun; Tschirner, Ulrike

    2010-01-01

    Switchgrass (Panicum virgatum), alfalfa stems (Medicago sativa), second year growth hybrid poplar (Populus) and willow (Salix spp.) were examined to determine fiber characteristics, pulping behavior and paper properties. Alfalfa stems and switchgrass both showed length weighted average fiber length (LWW) of 0.78 mm, a very narrow fiber length distribution and high fines content. Willow and hybrid poplar have lower fines content but a very low average fiber length (0.42 and 0.48 mm LWW). In addition, the four biomass species showed distinctly different chemical compositions. Switchgrass was defibered successfully using Soda and Soda Anthraquinone (AQ) pulping and demonstrated good paper properties. Both fast-growing wood species pulped well using the Kraft process, and showed acceptable tensile strength, but low tear strength. Alfalfa stems reacted very poorly to Soda and Soda AQ pulping but responded well to Kraft and Kraft AQ. Pulps with tensile and tear strength considerably higher than those found for commercial aspen pulps were observed for alfalfa. All four biomass species examined demonstrated low pulp yield. The highest yields were obtained with poplar and switchgrass (around 43%). Considering the short fibers and low yields, all four biomass types will likely only be used in paper manufacturing if they offer considerable economic advantage over traditional pulp wood.

  14. Composite tube cracking in kraft recovery boilers: A state-of-the-art review

    Energy Technology Data Exchange (ETDEWEB)

    Singbeil, D.L.; Prescott, R. [Pulp and Paper Research Inst. of Canada, Vancouver, British Columbia (Canada); Keiser, J.R.; Swindeman, R.W. [Oak Ridge National Lab., TN (United States)

    1997-07-01

    Beginning in the mid-1960s, increasing energy costs in Finland and Sweden made energy recovery more critical to the cost-effective operation of a kraft pulp mill. Boiler designers responded to this need by raising the steam operating pressure, but almost immediately the wall tubes in these new boilers began to corrode rapidly. Test panels installed in the walls of the most severely corroding boiler identified austenitic stainless steel as sufficiently resistant to the new corrosive conditions, and discussions with Sandvik AB, a Swedish tube manufacturer, led to the suggestion that coextruded tubes be used for water wall service in kraft recovery boilers. Replacement of carbon steel by coextruded tubes has solved most of the corrosion problems experienced by carbon steel wall tubes, however, these tubes have not been problem-free. Beginning in early 1995, a multidisciplinary research program funded by the US Department of Energy was established to investigate the cause of cracking in coextruded tubes and to develop improved materials for use in water walls and floors of kraft recovery boilers. One portion of that program, a state-of-the-art review of public- and private-domain documents related to coextruded tube cracking in kraft recovery boilers is reported here. Sources of information that were consulted for this review include the following: tube manufacturers, boiler manufacturers, public-domain literature, companies operating kraft recovery boilers, consultants and failure analysis laboratories, and failure analyses conducted specifically for this project. Much of the information contained in this report involves cracking problems experienced in recovery boiler floors and those aspects of spout and air-port-opening cracking not readily attributable to thermal fatigue. 61 refs.

  15. Isolation and characterization of lignocellulose nanofibers from different wheat straw pulps.

    Science.gov (United States)

    Sánchez, Rafael; Espinosa, Eduardo; Domínguez-Robles, Juan; Loaiza, Javier Mauricio; Rodríguez, Alejandro

    2016-11-01

    Wheat straw was cooked under different pulping processes: Soda (100°C, 7% NaOH, 150min), Kraft (170°C, 16% alkalinity, 25% sulfidity, 40min) and Organosolv (210°C, 60% ethanol, 60min). Once the pulps were obtained, lignocellulose nanofibers (LCNF) were isolated by mechanical process and TEMPO-mediated oxidation followed by a high pressure homogenization. After pulping process, the different pulps were characterized and its chemical composition was determined. The pulps characterization indicates that the Soda process is the process that, despite producing less delignification, retains much of the hemicelluloses in the pulp, being this content a key factor in the nanofibrillation process. Regarding the LCNF obtained by mechanical process, those nanofibers isolated from Organosolv wheat pulp (OWP) and Kraft wheat pulp (KWP) show low values for nanofibrillation yield, specific surface area and greater diameter. However, those nanofibers isolated from Soda wheat pulp (SWP) reach much higher values for these parameters and presents a diameter of 14nm, smaller than those obtained by TEMPO-mediated oxidation from OWP. Smaller diameters are generally obtained in TEMPO-oxidized LCNF. This work concludes that the lignin content does not affect greatly to obtain LCNF as does the hemicellulose content, so it is accurate to use a soft pulping process. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Structural characterization of Kraft lignins from different spent cooking liquors by 1D and 2D Nuclear Magnetic Resonance spectroscopy

    International Nuclear Information System (INIS)

    Fernández-Costas, C.; Gouveia, S.; Sanromán, M.A.; Moldes, D.

    2014-01-01

    Three Kraft lignins isolated from black liquors of several paper pulp mills of the North of Spain and Portugal were structurally characterized by using monodimensional ( 1 H and 13 C) and bidimensional Nuclear Magnetic Resonance (NMR) spectrometry. From the latter, 13 C– 1 H heteronuclear single quantum correlation (HSQC) and heteronuclear multiple bond correlation (HMBC) were employed. Lignins from black liquors are usually burned for power generation. Nevertheless, they could become high value added products within a biorefinery context. In that case, a good understanding of their structure is a prior step to transform them. From all the NMR techniques studied, HSQC has risen as the most powerful tool in lignin characterization. Kraft cooking conditions and the type of wood seem to be the main factors that determine the differences observed in the lignins. All the samples have shown an important decrease in the number of β–O–4′ linkages, due to the Kraft process, and resinol has become the most resistant linkage to the process. Moreover, all samples seem to be mainly linked to a one polysaccharide: xylan. Several parameters like S/G ratio, portion of phenolic and aliphatic hydroxyls, amount of aromatic protons and other structural aspects were also estimated. - Highlights: • Lignins from three Kraft spent liquors were obtained by acid precipitation. • Structural characterization of the dissolved lignins was performed by NMR. • Wood source and pulping conditions determine the lignin characteristics. • Kraft process implies cleavage of β–O–4 linkages and survival of resinol linkages. • Comparison of the samples would aid decisions on its future revalorization

  17. Kinetic modeling of formic acid pulping of bagasse.

    Science.gov (United States)

    Tu, Qiliang; Fu, Shiyu; Zhan, Huaiyu; Chai, Xinsheng; Lucia, Lucian A

    2008-05-14

    Organic solvent or organosolv pulping processes are alternatives to soda or kraft pulping to delignify lignocellulosic materials for the production of paper pulp. Formic acid, a typical organosolv system, has been presently examined under atmospheric pressure to pulp bagasse fibers. It was shown that efficient bagasse pulping was achieved when the formic acid concentration was limited to 90% (v/v). A statistical kinetic model based on the experimental results for the delignification of bagasse during formic acid pulping was developed that can be described as follows: D (delignification) = 0.747 x C(formicacid) (1.688) x (1 - e(-0.05171t)), an equation that can be used to predict the lignin content in formic acid during the pulping process. The delignification of bagasse by 90% formic acid was almost completed after approximately 80 min, while extended pulping did not improve the delignification but tended to degrade the carbohydrates in bagasse, especially the hemicelluloses, which were rapidly hydrolyzed at the onset of pulping.

  18. Chocolate spot of Eucalyptus

    OpenAIRE

    Cheewangkoon, R.; Groenewald, J.Z.; Hyde, K.D.; To-anun, C.; Crous, P.W.

    2012-01-01

    Chocolate Spot leaf disease of Eucalyptus is associated with several Heteroconium-like species of hyphomycetes that resemble Heteroconium s.str. in morphology. They differ, however, in their ecology, with the former being plant pathogenic, while Heteroconium s.str. is a genus of sooty moulds. Results of molecular analyses, inferred from DNA sequences of the large subunit (LSU) and internal transcribed spacers (ITS) region of nrDNA, delineated four Heteroconium-like species on Eucalyptus, name...

  19. Application Of Flash X-Ray Radiography To Problems In The Pulp And Paper Industry

    Science.gov (United States)

    Farrington, Theodore E.

    1988-02-01

    The use of flash x-ray radiography to investigate high speed multiphase flows is demonstrated. Both fundamental and practical problems of interest to the pulp and paper industry are used as examples. More specifically, studies of concentrated fiber suspension flows, kraft black liquor sprays and impulse drying are discussed.

  20. Combustion properties of kraft black liquors; Ligniinifraktion vaikutus mustalipeaen poltto-ominaisuuksiin

    Energy Technology Data Exchange (ETDEWEB)

    Alen, R.; Rantanen, K.; Ekman, J.; Malkavaara, P. [Jyvaeskylae Univ. (Finland)

    1996-12-01

    The aim of this investigation was to find relationships between the structure of the dissolved lignin and the combustion properties (pyrolysis time, char burning time, and swelling) of softwood and hardwood kraft black liquors. In this conjunction, pine and birch chips, as well as their two mixtures (the mass ratios of pine chips to birch chips were 80:20 and 60:40), were delignified by conventional kraft pulping. In each cook series, a liquor sample was withdrawn at certain time intervals to obtain liquor samples with different chemical composition. The black liquors obtained were analyzed with respect to the content of lignin and `lignin monomers`, but also the molecular-mass distribution and the mass average molecular mass of lignin were made. In addition, the dissolved lignin was characterized by NMR spectroscopy and elemental analysis. Further data on the chemical structures of lignin in black liquors were obtained by identifying various degradation products formed from this material during oxidative (CuO oxidation) and pyrolytic treatments. Several correlations between the `structural parameters` of the dissolved lignin and the combustion properties of black liquor were found. These correlations were significant especially in the case of pine cook. The results revealed many findings which are, together with the earlier data, useful for a better understanding of the thermochemical behavior of different kraft black liquors during combustion in a recovery furnace. (author)

  1. Alkaline Pulping and Bleaching of Acacia auriculiformis Grown in Bangladesh

    OpenAIRE

    JAHAN, M. Sarwar; SABINA, Rowshan; RUBAIYAT, Arjumand

    2014-01-01

    The physical, chemical, and morphological characteristics of Acacia auriculiformis were evaluated in terms of its suitability for papermaking. The fiber length (1.1 mm) of A. auriculiformis in this study was within the range of tropical hardwoods. The lignin content in A. auriculiformis was 19.4% and a-cellulose 44.1%, which was within the range of other acacias, but that of extractives was higher. Soda, soda-AQ, and kraft processes were studied in pulping. Screened pulp yield was increased w...

  2. Production of cellulose nanofibrils from bleached eucalyptus fibers by hyperthermostable endoglucanase treatment and subsequent microfluidization

    Science.gov (United States)

    Wangxia Wang; Michael D. Mozuch; Ronald C. Sabo; Phil Kersten; J.Y. Zhu; Yongcan Jin

    2015-01-01

    A GH5 hyperthermostable endoglucanase from the archaeon Pyrococcus honkoshii (ph-GH5) and a commercial endoglucanase FR were used to treat bleached eucalyptus pulp (BEP) fibers to produce cellulose nanofibrils (CNFs) through subsequent microfluidization Enzymatic treatments facilitated CNF production due to the reduced degree of polymerization (DP)...

  3. Mycosphaerella and Teratosphaeria species associated with leaf diseases on Eucalyptus globulus in southern Brazil

    NARCIS (Netherlands)

    Teodoro, M.G.; Ferreira, M.A.; Guimarães, L.M.S.; Mafia, R.G.; Groenewald, J.Z.; Crous, P.W.; Alfenas, A.C.

    2012-01-01

    Leaf blight and defoliation caused by Teratosphaeria species is one of the most important leaf diseases of Eucalyptus globulus. Due to the importance of this tree species for the production of pulp and paper, and recent reports of severe leaf disease symptoms in Brazil, the present study was

  4. Control of the Accumulation of Non-Process Elements in Pulp Mills with Bleach Filtrate Reuse: A Chemical Equilibrium Approach to Predicting the Partitioning of Metals in Pulp Mill and Bleach Plant Streams

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, W.J. Jr.; Rudie, A.W.; Schmidl, G.W.; Sinquefield, S.A.; Rorrer, G.L.; Laver, M.L.; Yantasee, W.; Ming, D.

    2000-08-01

    The overall goal of this project was to develop fundamental, experimentally based methods for predicting the solubility or organic and inorganic matter and their interactions in recycled effluent from kraft pulp mills and bleach plants. This included: characterizing the capacity of wood pulp and dissolved organic matter to bind metal ions, developing a thermodynamic database of properties needed to describe the solubility of inorganic matter in pulp mill streams, incorporation of the database into equilibrium calculation software for predicting the solubility of the metals of interest, and evaluating its capability to predict the distribution of the metals between pulp fibers, inorganic precipitates, and solution.

  5. Combining ability of elite clones of Eucalyptus grandis and Eucalyptus urophylla with Eucalyptus globulus

    OpenAIRE

    Bison,Odair; Ramalho,Magno Antonio Patto; Rezende,Gabriel Dehon Sampaio Peçanha; Aguiar,Aurélio Mendes; Resende,Marcos Deon Vilela de

    2007-01-01

    In Brazil, eucalyptus breeding programs for cellulose production has used two species, Eucalyptus grandis and Eucalyptus urophylla. Nevertheless, it would be useful to introgress alleles from other species to improve wood quality and volume. The objective of this research was to evaluate the hybrid potential of elite clones of E. grandis and E. urophylla from the Aracruz Celulose Company S. A. with Eucalyptus globulus clones. To do so, six elite clones were crossed with ten E. globulus clones...

  6. Preparation of lumen-loaded kenaf pulp with magnetite (Fe3O4)

    International Nuclear Information System (INIS)

    Zakaria, S.; Ong, B.H.; Ahmad, S.H.; Abdullah, M.; Yamauchi, T.

    2005-01-01

    Magnetic pulps were prepared from unbleached kenaf (hibiscus cannabinus L.) kraft pulps. Fe 3 O 4 or magnetite powder was used to load into the pulp's lumen and pit. Aluminum sulphate [Al 2 (SO 4 ) 3 ] (alum) and polyethylenimine (PEI), both mainly function as retention aid were used throughout the experiment and found to be beneficial in the preparation of this magnetic pulps. The ash content method was used to determine the amount of magnetite retained in the lumen and pit. The utilization of PEI up to 2% per pulp fibres was found to be the best result on lumen loading. The deposition of magnetite powder in lumen and pit is found decrease as the addition of PEI used is more than 2% per pulp fibres. Scanning electron microscope (SEM) clearly shows the distribution of magnetite deposited in the lumen. Tensile index and folding endurance of the loaded fibre decreased slightly as the percentage of loading pigment increased

  7. Kraft cooking of gamma irradiated wood, (1)

    International Nuclear Information System (INIS)

    Inaba, Masamitsu; Meshitsuka, Gyosuke; Nakano, Junzo

    1979-01-01

    Studies have been made of kraft cooking of gamma irradiated wood. Beech (Fagus crenata Blume) wood meal suspended in aqueous alkaline alcohol was irradiated up to 1.5 KGy (0.15 Mrad) with gamma rays from a Co-60 source in the presence or absence of oxygen. The irradiated wood meals were washed thoroughly with fresh water, air dried and cooked under the ordinary cooking conditions. The results are summarized as follows: (1) Pre-irradiation in aqueous alkali have negligible effect on kraft cooking. (2) In the case of ethanol addition (50 g/l), pre-irradiation in vacuo shows acceleration of delignification and stabilization of carbohydrates during kraft cooking. Cooked yield gain by pre-irradiation was about 1.2% in all over the range of delignification from 80 to 90%. Aqueous ethanol without alkali also shows positive but smaller effect than that with alkali. (3) Propanol, iso-propanol and butanol show positive but smaller effects than ethanol. However, methanol does not show any positive effect. (4) Irradiation in the presence of oxygen does not show any attractive effect on kraft cooking. (author)

  8. Ground beetle populations near a kraft mill

    Energy Technology Data Exchange (ETDEWEB)

    Freitag, R.; Hastings, L.; Mercer, W.R.; Smith, A.

    1973-02-01

    Twenty species of ground beetles (Family Carabidae) and one species of carrion beetle (Family Silphidae) were collected in six stations east of a kraft paper mill in Thunder Bay, Ontario, from May to August, 1971. The beetle population decreased markedly towards the mill. There was no apparent statistical difference in size variation of specimens near the mill and those further away.

  9. Production of biofuels from lignocellulosic biomass in pulp and paper mill effluents for low carbon society

    OpenAIRE

    Thakur, Indu Shekhar; Nakagoshi, Nobukazu

    2011-01-01

    Carbon Dioxide (CO2) is the most prominent Green House Gas (GHGs) in the Earth's atmosphere is responsible for climate change and other environmental problems. However, CO2 may be converted into organic compounds and lignocellulosic biomass. The pulp and paper mill is a major industrial sector utilizing huge amount of natural product (woody and non-woody plants), inorganic and organic materials along with large volume of water in different stages of the paper manufacturing. In kraft pulping, ...

  10. Eucalyptus oil overdose

    Science.gov (United States)

    Eucalyptus oil overdose occurs when someone swallows a large amount of a product that contains this oil. This can be by accident or on purpose. This article is for information only. DO NOT use it to treat or manage an actual overdose. If ...

  11. on black ironbark (Eucalyptus

    African Journals Online (AJOL)

    (Eucalyptus sideroxylon). B. Buys. Plant Protection Research Institute, Private Bag X5017,. Stellenbosch, 7600 Republic of South Africa. Received May /984; accepted 28 November /986. Black ironbark trees secrete nectar during the night. Argentine ants collected 42% of the nectar before honeybees started foraging in the ...

  12. Eucalyptus and Water Use in South Africa

    Directory of Open Access Journals (Sweden)

    Janine M. Albaugh

    2013-01-01

    Full Text Available The Eucalyptus genus yields high rates of productivity and can be grown across a wide range of site types and climates for products such as pulp, fuelwood, or construction lumber. In addition, many eucalypts have the ability to coppice, making this genus an ideal candidate for use as a biofuel feedstock. However, the water use of Eucalyptus is a controversial issue, and the impacts of these fast-growing trees on water resources are well documented. Regardless, the demand for wood products and water continues to rise, providing a challenge to increase the productivity of forest plantations within water constraints. This is of particular relevance for water-limited countries such as South Africa which relies on exotic plantations to meet its timber needs. Research results from water use studies in South Africa are well documented and legislation restrictions limit further afforestation. This paper outlines techniques used to quantify the water use of eucalypt plantations and provides recommendations on where to focus future research efforts. Greater insights into the water use efficiency of clonal material are needed, as certain eucalypt clones show fast growth and low water use. To better understand water use efficiency, estimates should be combined with monitoring of stand canopy structure and measurements of physiological processes.

  13. IMPORTANCE OF THE FORESTS PLANTATIONS OF Eucalyptus

    Directory of Open Access Journals (Sweden)

    Rosa Martínez Ruiz; Hilda S. Azpíroz Rivero; José Luís Rodríguez De la O.; Víctor M. CetinaAlcalá y M. A. Gutiérrez Espinoza

    2006-09-01

    Full Text Available SUMMARYThe worldwide consumption of wood is distributed between the energy necessities, firewood and charcoal (more than 50 %, the sawmill wood, posts, dismount and construction (20 % and the dedicated to the industry of the cellulose and the paper (27 %. The world previsions for the wood consumption in the year 2000 surpasses the 4000 m3 millions, what supposes a shortage of 1000 millions. There is a shortage in the world of wood as of energy, what converts to the forest production in priority objective. The Eucalyptus has been and is one of the forests resources industrially more used in the entire world. Originated from Australia, it presents an enormous diversity, with more than 600 different species. Its wood is suitable for many uses: domestic consumption, firewood of high calorific power, charcoal production, building structures, posts for communications, parquet ground, cellulose pulp, mine wood, bank subjection, or for fiber board manufacture. From its cellulose multiple products of daily use can be made for example: health paper swaddling clothes and hygienic, derived products as the cellophane or the wrapping paper, formic and other sheets, special papers, filters, electronic papers; as well as manufacture of textile fabrics as “rayon”. The request of derivation products of the eucalyptus wood is still very high world wide, the one that shows a sustained growth.

  14. Quality evaluation of dissolving pulp fabricated from banana plant stem and its potential for biorefinery.

    Science.gov (United States)

    Das, Atanu Kumar; Nakagawa-Izumi, Akiko; Ohi, Hiroshi

    2016-08-20

    The study was conducted to evaluate the quality of dissolving pulp of Musa sapientum L. (banana) plant stem and its potential for biorefinery. Introduction of pre-hydrolysis prior to any alkaline pulping process helps to reduce the content of hemicellulose and consequently produce acceptably high content of cellulose pulp. Water pre-hydrolysis was done at 150°C for 90min. The amount of lignin, xylan and glucan in the extracted pre-hydrolysis liquor (PHL) was 1.6, 4.9 and 1.6%, respectively. Pulping of pre-extracted chips was done following soda-AQ, alkaline sulfite and kraft process. The ratio of chip to liquor was 1:7 for both pre-hydrolysis and pulping. The kraft pulping process with 20% active alkali and 25% sulfidity at 150°C for 90min showed the best result. The lowest kappa number was 26.2 with a considerable pulp yield of 32.7%. The pulp was bleached by acidic NaClO2 and the consistency was 10% based on air-dried pulp. The lowest amount of 7% NaClO2 was used for the bleaching sequence of D0ED1ED2. After D0ED1ED2 bleaching, the pulp showed that α-cellulose, brightness and ash were 91.9, 77.9 and 1.6% respectively. The viscosity was 19.9cP. Hence, there is a possibility to use banana plant stem as a raw material for dissolving grade pulp and other bioproducts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Effect of replacing polyol by organosolv and kraft lignin on the property and structure of rigid polyurethane foam.

    Science.gov (United States)

    Pan, Xuejun; Saddler, Jack N

    2013-01-28

    Lignin is one of the three major components in plant cell walls, and it can be isolated (dissolved) from the cell wall in pretreatment or chemical pulping. However, there is a lack of high-value applications for lignin, and the commonest proposal for lignin is power and steam generation through combustion. Organosolv ethanol process is one of the effective pretreatment methods for woody biomass for cellulosic ethanol production, and kraft process is a dominant chemical pulping method in paper industry. In the present research, the lignins from organosolv pretreatment and kraft pulping were evaluated to replace polyol for producing rigid polyurethane foams (RPFs). Petroleum-based polyol was replaced with hardwood ethanol organosolv lignin (HEL) or hardwood kraft lignin (HKL) from 25% to 70% (molar percentage) in preparing rigid polyurethane foam. The prepared foams contained 12-36% (w/w) HEL or 9-28% (w/w) HKL. The density, compressive strength, and cellular structure of the prepared foams were investigated and compared. Chain extenders were used to improve the properties of the RPFs. It was found that lignin was chemically crosslinked not just physically trapped in the rigid polyurethane foams. The lignin-containing foams had comparable structure and strength up to 25-30% (w/w) HEL or 19-23% (w/w) HKL addition. The results indicated that HEL performed much better in RPFs and could replace more polyol at the same strength than HKL because the former had a better miscibility with the polyol than the latter. Chain extender such as butanediol could improve the strength of lignin-containing RPFs.

  16. Effect of replacing polyol by organosolv and kraft lignin on the property and structure of rigid polyurethane foam

    Directory of Open Access Journals (Sweden)

    Pan Xuejun

    2013-01-01

    Full Text Available Abstract Background Lignin is one of the three major components in plant cell walls, and it can be isolated (dissolved from the cell wall in pretreatment or chemical pulping. However, there is a lack of high-value applications for lignin, and the commonest proposal for lignin is power and steam generation through combustion. Organosolv ethanol process is one of the effective pretreatment methods for woody biomass for cellulosic ethanol production, and kraft process is a dominant chemical pulping method in paper industry. In the present research, the lignins from organosolv pretreatment and kraft pulping were evaluated to replace polyol for producing rigid polyurethane foams (RPFs. Results Petroleum-based polyol was replaced with hardwood ethanol organosolv lignin (HEL or hardwood kraft lignin (HKL from 25% to 70% (molar percentage in preparing rigid polyurethane foam. The prepared foams contained 12-36% (w/w HEL or 9-28% (w/w HKL. The density, compressive strength, and cellular structure of the prepared foams were investigated and compared. Chain extenders were used to improve the properties of the RPFs. Conclusions It was found that lignin was chemically crosslinked not just physically trapped in the rigid polyurethane foams. The lignin-containing foams had comparable structure and strength up to 25-30% (w/w HEL or 19-23% (w/w HKL addition. The results indicated that HEL performed much better in RPFs and could replace more polyol at the same strength than HKL because the former had a better miscibility with the polyol than the latter. Chain extender such as butanediol could improve the strength of lignin-containing RPFs.

  17. Effect of replacing polyol by organosolv and kraft lignin on the property and structure of rigid polyurethane foam

    Science.gov (United States)

    2013-01-01

    Background Lignin is one of the three major components in plant cell walls, and it can be isolated (dissolved) from the cell wall in pretreatment or chemical pulping. However, there is a lack of high-value applications for lignin, and the commonest proposal for lignin is power and steam generation through combustion. Organosolv ethanol process is one of the effective pretreatment methods for woody biomass for cellulosic ethanol production, and kraft process is a dominant chemical pulping method in paper industry. In the present research, the lignins from organosolv pretreatment and kraft pulping were evaluated to replace polyol for producing rigid polyurethane foams (RPFs). Results Petroleum-based polyol was replaced with hardwood ethanol organosolv lignin (HEL) or hardwood kraft lignin (HKL) from 25% to 70% (molar percentage) in preparing rigid polyurethane foam. The prepared foams contained 12-36% (w/w) HEL or 9-28% (w/w) HKL. The density, compressive strength, and cellular structure of the prepared foams were investigated and compared. Chain extenders were used to improve the properties of the RPFs. Conclusions It was found that lignin was chemically crosslinked not just physically trapped in the rigid polyurethane foams. The lignin-containing foams had comparable structure and strength up to 25-30% (w/w) HEL or 19-23% (w/w) HKL addition. The results indicated that HEL performed much better in RPFs and could replace more polyol at the same strength than HKL because the former had a better miscibility with the polyol than the latter. Chain extender such as butanediol could improve the strength of lignin-containing RPFs. PMID:23356502

  18. Biopulping of sugarcane bagasse and decolorization of kraft liquor by the laccase produced by Klebsiella aerogenes NCIM 2098

    Directory of Open Access Journals (Sweden)

    Jha H.

    2013-12-01

    Full Text Available Aims: Laccase, a copper-containing enzyme, oxidizes variety of aromatic compounds. Since laccase is essential for lignin degradation, it can be used for lignin removal in the pulp and paper industry (biopulping. Laccase is also employed as a dechlorinating agent (biobleaching, along with the removal of phenolic and other aromatic pollutants. In the present investigation it was aimed to employ the laccase produced by the bacterium Klebsiella aerogenes along with the bacterium itself in biopulping of sugarcane bagasse and biobleaching of kraft liquor effluent. Methodology and results: A laccase was isolated from the bacterium K. aerogenes, purified to homogeneity and characterized. The enzyme was purified by conventional techniques following salt precipitation, ion exchange chromatography, and affinity chromatography on Con A sepharose. The purified laccase was found to be monomeric glycoprotein with a Mr of 64 kDa when measured by Sephadex G-200 gel chromatography and SDS-PAGE. The Vmax and Km of laccase towards the substrate guaiacol was determined. The optimum pH of the laccase was found to be 5.0. biopulping and biobleaching activities were determined by TAPPI standard methods. Treatment of sugarcane baggase by K. aerogenes also significantly reduced lignin content of the bagasse. Conclusion, significance and impact of study: The bacterium K. aerogenes and a laccase produced by it were used separately for biopulping of sugarcane bagasse and biobleaching of kraft liquor effluent. Treatment with both brought significant reduction in lignin content and kappa number of the pulp. The handsheets prepared from the treated pulp showed improved brightness without affecting the strength properties of paper. The bacterium and the laccase efficiently decolorized the kraft liquor proving to have biobleaching potential.

  19. Durability of pulp fiber-cement composites

    Science.gov (United States)

    Mohr, Benjamin J.

    Wood pulp fibers are a unique reinforcing material as they are non-hazardous, renewable, and readily available at relatively low cost compared to other commercially available fibers. Today, pulp fiber-cement composites can be found in products such as extruded non-pressure pipes and non-structural building materials, mainly thin-sheet products. Although natural fibers have been used historically to reinforce various building materials, little scientific effort has been devoted to the examination of natural fibers to reinforce engineering materials until recently. The need for this type of fundamental research has been emphasized by widespread awareness of moisture-related failures of some engineered materials; these failures have led to the filing of national- and state-level class action lawsuits against several manufacturers. Thus, if pulp fiber-cement composites are to be used for exterior structural applications, the effects of cyclical wet/dry (rain/heat) exposure on performance must be known. Pulp fiber-cement composites have been tested in flexure to examine the progression of strength and toughness degradation. Based on scanning electron microscopy (SEM), environmental scanning electron microscopy (ESEM), energy dispersive spectroscopy (EDS), a three-part model describing the mechanisms of progressive degradation has been proposed: (1) initial fiber-cement/fiber interlayer debonding, (2) reprecipitation of crystalline and amorphous ettringite within the void space at the former fiber-cement interface, and (3) fiber embrittlement due to reprecipitation of calcium hydroxide filling the spaces within the fiber cell wall structure. Finally, as a means to mitigate kraft pulp fiber-cement composite degradation, the effects of partial portland cement replacement with various supplementary cementitious materials (SCMs) has been investigated for their effect on mitigating kraft pulp fiber-cement composite mechanical property degradation (i.e., strength and toughness

  20. From research to innovation: The case of biotechnical pulp bleaching

    Energy Technology Data Exchange (ETDEWEB)

    Miettinen, R.

    1996-05-01

    The paper studies the emergence and development of a research-based innovation, enzyme-aided bleaching of kraft pulp. The idea of a new bleaching method was formulated in a meeting at the Biotechnical Laboratory of Technical Research Centre of Finland (VTT) in January 1984. The method was based on the use of hemicellulases. The Biotechnology Laboratory has actively studied hemicellulases for several years and they were hence immediately available for experiments. The Biotechnology Laboratory collaborated with the Fibre Chemistry Laboratory of the Finnish Pulp and Paper Research Institute (FPPRI), which knew different kinds of pulps and was skilled in the analysis of their paper technical qualities. With this combination of knowledge the results were achieved without delay.

  1. Engineering structural integrity issues in the pulp and paper industry

    International Nuclear Information System (INIS)

    Garner, A.; Singbeil, D.

    2002-01-01

    ESI issues for Pulp and Paper (P and P) plant are reviewed. Five typical processes are covered, namely: Chemical Pulping, Bleaching, Chemical Recovery, Mechanical Pulping and Papermaking. Equipment, chemical environments and failure modes are summarized with examples from each process. Pressure, temperature, corrosion and rotation are typical sources of risk, which is managed by appropriate inspection. The nature of the P and P Industry and its technology supply is summarized: current trends are consolidation and outsourcing. Three examples are presented to illustrate typical ESI issues: deaerator cracking where the P and P Industry alerted others to this serious cross-industry problem; pressure vessel safety factors and inconsistent international codes; and caustic cracking in continuous kraft digesters, which required rapid and concerted action to diagnose and control. In the future better predictability, data-bases, more formal risk based inspection and fitness-for-service assessments are envisaged. (author)

  2. Complex linkage between soil, soil water, atmosphere and Eucalyptus Plantations

    Science.gov (United States)

    Shukla, C.; Tiwari, K. N.

    2017-12-01

    Eucalyptus is most widely planted genus grown in waste land of eastern region of India to meet the pulp industry requirements. Sustainability of these plantations is of concern because in spite of higher demand water and nutrients of plantations, they are mostly planted on low-fertility soils. This study has been conducted to quantify effect of 25 years old, a fully established eucalyptus plantations on i.) Alteration in physico-chemical and hydrological properties of soil of eucalyptus plantation in comparison to soil of natural grassland and ii.) Spatio-temporal variation in soil moisture under eucalyptus plantations. Soil physico-chemical properties of two adjacent plots covered with eucatuptus and natural grasses were analyzed for three consecutive depths (i.e. 0-30 cm, 30-60 cm and 60-90 cm) with five replications in each plot. Soil infiltration rate and saturated hydraulic conductivity (Ks) were measured in-situ to incorporate the influence of macro porosity caused due to roots of plantations. Daily soil moisture at an interval of 10 cm upto 160 cm depth with 3 replications and Leaf Area Index (LAI) at an interval of 15 days with 5 replications were recorded over the year. Significant variations found at level of 0.05 between soil properties of eucalyptus and natural grass land confirm the effect of plantations on soil properties. Comparative results of soil properties show significant alteration in soil texture such as percent of sand, organic matter and Ks found more by 20%, 9% and 22% respectively in eucalyptus plot as compare to natural grass land. Available soil moisture (ASM) was found constantly minimum in top soil excluding rainy season indicate upward movement of water and nutrients during dry season. Seasonal variation in temperature (T), relative humidity (RH) and leaf area index (LAI) influenced the soil moisture extraction phenomenon. This study clearly stated the impact of long term establishment of eucalyptus plantations make considerable

  3. Permeability measuremens of brazilian Eucalyptus

    Directory of Open Access Journals (Sweden)

    Marcio Rogério da Silva

    2010-09-01

    Full Text Available The permeability of Brazilian Eucalyptus grandis and Eucalyptus citriodora wood was measured in a custom build gas analysis chamber in order to determine which species could be successfully treated with preservatives. Liquid permeability was tested using an emulsion of Neen oil and a control of distillated water. Air was used to test the gas phase permeability. For both Eucalyptus grandis and Eucalyptus citriodora, the longitudinal permeability of gas was shown to be about twice as great as the liquid phase permeability. No radial permeability was observed for either wood. The permeability of air and water through the sapwood of Eucalyptus grandis was greater than that through the sapwood of Eucalyptus citriodora. The permeability of neen oil preservative through the sapwood of Eucalyptus grandis was also greater than through the sapwood of E. Citradora, but the difference was not statistically significant. Scanning Electron Microscopy images showed that the distribution and obstruction in the vessels could be correlated with observed permeability properties. Irrespective of the causes of differences in permeability between the species, the fluid phase flux through the sapwood of both species was significant, indicating that both Eucalyptus grandis and Eucalyptus citriodora could be successfully treated with wood preservative.

  4. Water relations of Eucalyptus nitens x Eucalyptus grandis : is there ...

    African Journals Online (AJOL)

    Water relations of Eucalyptus nitens x Eucalyptus grandis : is there interclonal variation in response to experimentally imposed water stress? ... Southern Forests: a Journal of Forest Science ... However, water stress reduced shoot hydraulic conductance and stem hydraulic conductivity with significant interclonal effects.

  5. Effect of eucalyptus ( Eucalyptus camaldulensis ) and maize (Zea ...

    African Journals Online (AJOL)

    In Senegal, farmers often cultivate groundnut in association with eucalyptus plantations to increase their incomes. However eucalyptus plantations produce large amounts of litter, which impact on groundnut has not been clearly elucidated yet. In order to investigate litter accumulation effect on growth, development, and ...

  6. A principal component approach for predicting the stem volume in Eucalyptus plantations in Brazil using airborne LiDAR data

    Science.gov (United States)

    Carlos Alberto Silva; Carine Klauberg; Andrew T. Hudak; Lee A. Vierling; Veraldo Liesenberg; Samuel P. C. e Carvalho; Luiz C. E. Rodriguez

    2016-01-01

    Improving management practices in industrial forest plantations may increase production efficiencies, thereby reducing pressures on native tropical forests for meeting global pulp needs. This study aims to predict stem volume (V) in plantations of fast-growing Eucalyptus hybrid clones located in southeast Brazil using field plot and airborne Light Detection...

  7. Modification of pine pulp during oxygen delignification by xylan self-assembly.

    Science.gov (United States)

    Grigoray, Olga; Järnström, Joakim; Heikkilä, Elina; Fardim, Pedro; Heinze, Thomas

    2014-11-04

    Self-assembly is a technique of preparing functional materials based on targeted intermolecular interactions involving different macromolecules. In this work, hardwood xylan was disassembled from wood and birch bleached kraft pulp using pressurized hot water extraction (HWX) and cold alkali extraction (CAX), respectively. The extracted biopolymers were characterized using gas chromatography (GC), size exclusion chromatography (SEC) and Fourier transform infrared spectroscopy (FTIR), and subsequently added into an oxygen delignification reactor containing pine kraft pulp. The assembly of xylan-pulp fiber was characterized using advanced time-of-flight secondary ion mass spectrometry (ToF-SIMS) and imaging. The xylan-pine pulp assembly was not significantly removed during the whole elemental chlorine free bleaching sequence or during low consistency refining. Modified fibers had superior mechanical properties compared to the reference pulp. Our concept can be easily applied in the pulp and paper industry, and it opens new possibilities for the utilization of fully bio-based fibers in new materials. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Membrane treatment of alkaline bleaching effluents from elementary chlorine free kraft softwood cellulose production.

    Science.gov (United States)

    Oñate, Elizabeth; Rodríguez, Edgard; Bórquez, Rodrigo; Zaror, Claudio

    2015-01-01

    This paper reports experimental results on the sequential use of ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) to fractionate alkaline extraction bleaching effluents from kraft cellulose production. The aim was to unveil the way key pollutants are distributed when subjected to sequential UF/NF/RO membrane separation processes. Alkaline bleaching effluents were obtained from a local pinewood-based mill, featuring elementary chlorine free bleaching to produce high-brightness cellulose. The experimental system was based on a laboratory-scale membrane system, DSS LabStak® M20 Alfa Laval, using Alfa Laval UF and NF/RO membranes, operated at a constant transmembrane pressure (6 bar for UF membranes and 32 bar for NF/RO membranes), at 25°C. Results show that 78% chemical oxygen demand (COD) and total phenols, 82% adsorbable organic halogens (AOX) and 98% colour were retained by UF membranes which have molecular weight cut-off (MWCO) above 10 kDa. In all, 16% of original COD, total phenols and AOX, and the remaining 2% colour were retained by UF membranes within the 1 to 10 kDa MWCO range. Chloride ions were significantly present in all UF permeates, and RO was required to obtain a high-quality permeate with a view to water reuse. It is concluded that UF/NF/RO membranes offer a feasible option for water and chemicals recovery from alkaline bleaching effluents in kraft pulp production.

  9. Molecular weight distribution of Pinus radiata kraft mill wastewater treated by anaerobic digestion.

    Science.gov (United States)

    Vidal, G; Videla, S; Diez, M C

    2001-04-01

    Kraft mill is responsible for massive discharge of highly polluted effluents. The main characteristics of this effluent are high toxicity and low biodegradability due to tannin, lignin and chlorophenol compounds. The composition may vary dramatically depending, for instance, on the utilised feedstock and process. The purpose of this work was to investigate the molecular weight distribution of Pinus radiata kraft pulping wastewater treated by anaerobic digestion by using two types of anaerobic reactors: fixed bed and sludge blanket. Anaerobic sludge blanket (UASB) and anaerobic filter (AF) were operated. In both reactors, the total alkalinity ranged between 1.0 and 1.5 g CaCO3/l, while the organic load rate (OLR) was increasing during operation from 1.2 to 3.3 gCOD/l d. COD and total phenolic compounds (UV215) removal ranged between 30-50% and 13-20%, respectively, while the BOD5 removal ranged 60-90%. However only a partial biodegradation (10-43%) of tannin and lignin was observed. Results from ultrafiltration analyses indicated that the fraction with a molecular weight (MW) 10,000 MW fraction, colour and COD fraction increased by 14% and 5%, respectively, after anaerobic treatment. It can be concluded from this study, that treatment with UASB or AF reactors is not enough, under the conditions tested, for a large COD removal from Pinus radiata wastewater.

  10. Effects of Kraft Mill effluent on the sexuality of fishes: An environmental early warning

    Energy Technology Data Exchange (ETDEWEB)

    Davis, W.P.; Bortone, S.A.

    1992-01-01

    Arrhenoid or masculinized female fish species of the live-bearing family, Poeciliidae, have been observed for over thirteen years in specific southern streams which receive waste effluents from pulping mills. The complex mixture of organic compounds in kraft mill effluent (KME) has inhibited specific identification of causal agent(s). However, microbially degraded phytosterols (e.g. sitosterol or stigmastanol) in experimental exposures induce the same intersexual states that characterize affected female poeciliids sampled from KME streams. KME-polluted streams often exhibit a drastic reduction of fish species diversity and degrees of physiological stress, all of which suggests reduced reproduction in surviving forms. A potential ontogenetic or developmental response is demonstrated in American eels captured in one of these streams as well. The authors examine available information, including laboratory and experimental field exposures, and suggest directions for additional research as well as the need for environmental concern.

  11. Eucalyptus microsatellites mined in silico

    Indian Academy of Sciences (India)

    https://www.ias.ac.in/article/fulltext/jgen/087/01/0021-0025 ... Eucalyptus is an important short rotation pulpy woody plant, grown widely in the tropics. ... In this study, in silico analysis of 15,285 sequences representing partial and full-length mRNA from Eucalyptus species for their use in developing SSRs or microsatellites ...

  12. Fundamental understanding of distracted oxygen delignification efficiency by dissolved lignin during biorefinery process of eucalyptus.

    Science.gov (United States)

    Zhao, Huifang; Li, Jing; Zhang, Xuejin

    2018-02-27

    In this work, a fundamental understanding of oxygen delignification distracted by dissolved lignin was investigated. In the new biorefinery model of shortening kraft pulping integrated with extended oxygen delignification process, increasing content of residual lignin in the original pulp could result in enhanced delignification efficiency, higher pulp viscosity and less carbonyl groups. However, the invalid oxygen consumption by dissolved lignin could be increased with the increase of process temperature and alkali dosage. The normalized ultraviolet absorbance (divided by absorbance at 280 nm) also showed that the content of chromophoric group in dissolved lignin decreased with oxygen delignification proceeded, both of which indicated that dissolved lignin could enhance the invalid oxygen consumption. Therefore, a conclusion that replacement of the liquor at the initial phase of oxygen delignification process would balance the enhancement of delignification efficiency and invalid oxygen consumption was achieved. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Integrating black liquor gasification with pulping - Process simulation, economics and potential benefits

    Science.gov (United States)

    Lindstrom, Erik Vilhelm Mathias

    Gasification of black liquor could drastically increase the flexibility and improve the profit potential of a mature industry. The completed work was focused on research around the economics and benefits of its implementation, utilizing laboratory pulping experiments and process simulation. The separation of sodium and sulfur achieved through gasification of recovered black liquor, can be utilized in processes like modified continuous cooking, split sulfidity and green liquor pretreatment pulping, and polysulfide-anthraquinone pulping, to improve pulp yield and properties. Laboratory pulping protocols have been developed for these modified pulping technologies and different process options evaluated. The process simulation work around BLG has led to the development of a WinGEMS module for the low temperature MTCI steam reforming process, and case studies comparing a simulated conventional kraft process to different process options built around the implementation of a BLG unit operation into the kraft recovery cycle. Pulp yield increases of 1-3% points with improved product quality, and the potential for capital and operating cost savings relative to the conventional kraft process have been demonstrated. Process simulation work has shown that the net variable operating cost for a pulping process using BLGCC is highly dependent on the cost of lime kiln fuel and the selling price of green power to the grid. Under the assumptions taken in the performed case study, the BLGCC process combined with split sulfidity or PSAQ pulping operations had net variable operating cost 2-4% greater than the kraft reference. The influence of the sales price of power to the grid is the most significant cost factor. If a sales price increase to 6 ¢/KWh for green power could be achieved, cost savings of about $40/ODtP could be realized in all investigated BLG processes. Other alternatives to improve the process economics around BLG would be to modify or eliminate the lime kiln unit

  14. [Vital pulp therapy of damaged dental pulp].

    Science.gov (United States)

    Xuedong, Zhou; Dingming, Huang; Jianguo, Liu; Zhengwei, Huang; Xin, Wei; Deqin, Yang; Jin, Zhao; Liming, Chen; Lin, Zhu; Yanhong, Li; Jiyao, Li

    2017-08-01

    The development of an expert consensus on vital pulp therapy can provide practical guidance for the improvement of pulp damage care in China. Dental pulp disease is a major type of illness that adversely affects human oral health. Pulp capping and pulpotomy are currently the main methods for vital pulp therapy. Along with the development of minimal invasion cosmetic dentistry, using different treatment technologies and materials reasonably, preserving healthy tooth tissue, and extending tooth save time have become urgent problems that call for immediate solution in dental clinics. This paper summarizes the experiences and knowledge of endodontic experts. We develop a clinical path of vital pulp therapy for clinical work by utilizing the nature, approach, and degree of pulp damage as references, defense and self-repairing ability of pulp as guidance, and modern technologies of diagnosis and treatment as means.

  15. Acid bi-sulphite pulping effects on hardwoods and a softwood revealed by atomic force microscopy

    CSIR Research Space (South Africa)

    Chunilall, Viren

    2009-12-01

    Full Text Available aggregation of cellulose fibril aggregates (CFA) during processing in order to preserve the reactivity of dissolving pulp. Previous atomic force microscopy (AFM) studies on a species of Eucalyptus showed that there is an increase in the CFA dimensions during...

  16. The role of bleaching in pulp mill effluent effects on fish

    Energy Technology Data Exchange (ETDEWEB)

    Coakley, J.; Hodson, P.; Cross, T. [Queen`s Univ., School of Environmental Studies, Queen`s Univ., Kingston, ON (Canada); Van Heiningen, A. [New Brunswick Univ., Limerick Pulp and Paper Centre, Fredericton, NB (Canada)

    1999-05-01

    Sources and potency of mixed function oxygenase (MFO)-inducing compounds within a 5-stage chlorine dioxide bleaching sequence at a pulp and paper mill was determined. Environmental concerns regarding chlorinated organic materials and their toxicity to aquatic organisms caused many mills to switch to elemental chlorine-free bleaching processes, with the most common being the chlorine dioxide bleaching process. However, even with this switch, effluent from kraft pulp mills still affect aquatic organisms. In this study, bleach plant filtrates were collected from two kraft mills in Ontario. The filtrates were used in fish bioassays to assess MFO-inducing potency. Results showed that potency varied depending on the wood used (softwood or hardwood) and the bleaching stage. Filtrates produced in a lab were weak MFO inducers compared to mill filtrates.14 refs., 6 figs.

  17. Biological, medicinal and toxicological significance of Eucalyptus leaf essential oil: a review.

    Science.gov (United States)

    Dhakad, Ashok K; Pandey, Vijay V; Beg, Sobia; Rawat, Janhvi M; Singh, Avtar

    2018-02-01

    The genus Eucalyptus L'Heritier comprises about 900 species, of which more than 300 species contain volatile essential oil in their leaves. About 20 species, within these, have a high content of 1,8-cineole (more than 70%), commercially used for the production of essential oils in the pharmaceutical and cosmetic industries. However, Eucalyptus is extensively planted for pulp, plywood and solid wood production, but its leaf aromatic oil has astounding widespread biological activities, including antimicrobial, antiseptic, antioxidant, chemotherapeutic, respiratory and gastrointestinal disorder treatment, wound healing, and insecticidal/insect repellent, herbicidal, acaricidal, nematicidal, and perfumes, soap making and grease remover. In the present review, we have made an attempt to congregate the biological ingredients of leaf essential oil, leaf oil as a natural medicine, and pharmacological and toxicological values of the leaf oil of different Eucalyptus species worldwide. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Fermentation and chemical treatment of pulp and paper mill sludge

    Science.gov (United States)

    Lee, Yoon Y; Wang, Wei; Kang, Li

    2014-12-02

    A method of chemically treating partially de-ashed pulp and/or paper mill sludge to obtain products of value comprising taking a sample of primary sludge from a Kraft paper mill process, partially de-ashing the primary sludge by physical means, and further treating the primary sludge to obtain the products of value, including further treating the resulting sludge and using the resulting sludge as a substrate to produce cellulase in an efficient manner using the resulting sludge as the only carbon source and mixtures of inorganic salts as the primary nitrogen source, and including further treating the resulting sludge and using the resulting sludge to produce ethanol.

  19. COMBUSTION PROPERTIES OF EUCALYPTUS WOOD

    Directory of Open Access Journals (Sweden)

    Yalçın ÖRS

    1999-03-01

    Full Text Available In this study, the combustion properties of some impregnation materials (abiotic and biotic factors used for eucalyptus wood in interior or exterior environments were investigated. The experimental samples were prepared from Eucalyptus wood based on ASTM-D-1413-76 Tanalith-CBC, boric acid, borax, vacsol-WR, immersol-WR, polyethylen glycole-400 and ammonium sulphate were used as an impregnation material. The results indicated that, vacuum treatment on Eucalyptus gave the lowest retention value of salts. Compounds containing boron+salt increased fire resistance however water repellents decreased the wood flammability.

  20. Polymerisation of Kraft lignin from black liquors by laccase from Myceliophthora thermophila: effect of operational conditions and black liquor origin.

    Science.gov (United States)

    Gouveia, S; Fernández-Costas, C; Sanromán, M A; Moldes, D

    2013-03-01

    The capacity of laccase from Myceliophthora thermophila to promote the oxidative polymerisation of Kraft lignin (KL) was evaluated in several conditions of pH, temperature, enzyme dosage and treatment time. Moreover, different black liquors from the Kraft cooking of Eucalyptus globulus and mixture of Pinus pinaster/E. globulus were evaluated in order to determine the effect of the KL source on the polymerisation reaction. Furthermore, one of these black liquors was fractionated by sequential organic solvent fractionation and the polymerisation of the corresponding fractions was tested. Polymerisation products were analysed by size exclusion chromatography and Fourier transform infrared spectroscopy. The results provide evidence of notable lignin modifications after incubation with laccase. Structural oxidation and a notably molecular weight increase were attained, reaching a polymer of 69-fold its initial molecular weight depending on the raw lignin. Moreover, optimum values of reaction conditions were obtained: pH 7.3, 70°C, 2UmL(-1) and 2h. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Pretreatment of pulp mill secondary sludge for high-rate anaerobic conversion to biogas.

    Science.gov (United States)

    Wood, Nicholas; Tran, Honghi; Master, Emma

    2009-12-01

    Three pretreatment methods were compared based on their ability to increase the extent and rate of anaerobic bioconversion of pulp mill secondary sludge to biogas. The pretreatment technologies used in these experiments were: (i) thermal pretreatment performed at 170 degrees C; (ii) thermochemical (caustic) pretreatment performed at pH 12 and 140 degrees C; and (iii) sonication performed at 20 kHz and 1 W mL(-1). Sludge samples were obtained from a sulfite and a kraft pulp mill, and biochemical methane potential (BMP) assays were performed using microbial granules obtained from a high-rate anaerobic digester operating at a pulp mill. Biogas production from untreated sludge was 0.05 mL mg(-1) of measured chemical oxygen demand (COD) and 0.20 mL mg(-1) COD for kraft and sulfite sludge, respectively. Thermal pretreatment had the highest impact on sludge biodegradability. In this case, biogas yield and production rate from sulfite sludge increased by 50% and 10 times, respectively, while biogas yield and production rate from kraft sludge increased by 280% and 300 times, respectively. Biogas yield correlated to soluble carbohydrate content better than soluble COD.

  2. Fibre losses during debranching and debarking of Eucalyptus pulp ...

    African Journals Online (AJOL)

    Mechanised harvesting operations are becoming more prevalent in South Africa, with the realisation that motormanual and manual harvesting operations pose significant health and safety risks to workers. However, the potential damage caused by single-grip harvester feed rollers and delimbing knives on the log surface ...

  3. Identification of the CAD gene from Eucalyptus urophylla GLU4 and its functional analysis in transgenic tobacco.

    Science.gov (United States)

    Chen, B W; Xiao, Y F; Li, J J; Liu, H L; Qin, Z H; Gai, Y; Jiang, X N

    2016-12-02

    Cinnamyl alcohol dehydrogenase (CAD) catalyzes the final step in lignin biosynthesis. The genus Eucalyptus belongs to the family Myrtaceae, which is the main cultivated species in China. Eucalyptus urophylla GLU4 (GLU4) is widely grown in Guangxi. It is preferred for pulping because of its excellent cellulose content and fiber length. Based on GLU4 and CAD gene expression, a Eucalyptus variety low in lignin content should be obtained using transgenic technology, which could reduce the cost of pulp and improve the pulping rate, and have favorable prospects for application. However, the role and function of CAD in GLU4 is still unclear. In the present study, EuCAD was cloned from GLU4 and identified using bioinformatic tools. Subsequently, in order to evaluate its impact on lignin synthesis, a full-length EuCAD RNAi vector was constructed, and transgenic tobacco was obtained via Agrobacterium-mediated transformation. A significant decrease in CAD expression and lignin content in transgenic tobacco demonstrated a key role for EuCAD in lignin biosynthesis and established a regulatory role for RNAi. In our study, the direct molecular basis of EuCAD expression was determined, and the potential regulatory effects of this RNAi vector on lignin biosynthesis in E. urophylla GLU4 were demonstrated. Our results provide a theoretical basis for the study of lignin biosynthesis in Eucalyptus.

  4. The degradation of kraft lignin during hydrothermal treatment for phenolics

    Directory of Open Access Journals (Sweden)

    Tang Kai

    2015-09-01

    Full Text Available Kraft lignin was hydrothermally depolymerized at low temperature/short time in water for producing value-added phenolics. The effects of residence time (15, 60 min and reaction temperature (130, 180, 230ºC on yields of oils and phenolic compounds were studied in detail. Total oil yield was found to range between 7% and 10%. The compositions of oils were analyzed by GC-MS to confirm the main compound to be guaiacol (2-methoxy phenol in the range of 12–55% of oil depending on different reaction conditions. The most interesting was the finding that maximum value of total oil yield (10% of kraft lignin and guaiacol amount (55% of oil was obtained at 130ºC/15, 60 min which is a low reaction temperature/short time, while the residual kraft lignins were analyzed by FTIR with respect to the conversion mechanism of kraft lignin by this process.

  5. AVALIAÇÃO DOS RESÍDUOS DE UMA SERRARIA PARA A PRODUÇÃO DE CELULOSE KRAFT

    Directory of Open Access Journals (Sweden)

    Lucas Cândido Barbosa

    2014-01-01

    Full Text Available The forest-based industries have low yield and generate large amounts of waste, especially the primary processing industries, such as sawmills. In Brazil, initiatives are being created to combine the use of sawmill residues to pulp production. With this in mind, this study aimed to evaluate the performance of amedium-sized sawmill in the city of Rio Grande, in Rio Grande do Sul state, and to promote physical and chemical analysis of waste wood generated in the sawing process. It was used 20 logs of Pinus elliottii , divided into two diameter classes. The residues, except the sawdust, collected for analysis were disposed in the courtyard of the company in the form of chips. The following physical and chemical properties of the chips were examined: density, extractives content soluble in acetone, acetyl groups, soluble and insoluble lignin on acid (Klason lignin, uronic groups and carbohydrates. Comparing the results of the wood properties to the ones found in literature, it was evaluated the quantity and quality of waste that can be used as feedstock for the production of kraft pulp. As the main results there was a slight increase of sawing yields in the larger diameters logs compared to the smaller diameters. From the physical and chemical analyses, it was obtained the following results: density of 0.402 g / cm ³, cellulose content of 43.67% and 24.37% for hemicellulose, klason lignin of 26.75% and 3,80% for extractives content. As conclusion, the low sawing yield can be associated to the lack of a classification diametric and appropriate diagrams sections, resulting in a greater loss in the form of waste. Regarding the chemical and physical composition of the sawmill residues, the results were within the standards of quality wood used for kraft pulp of softwood material, presenting some advantages over younger woods commonly used in industry.

  6. Plants in energy field. Eucalyptus. II

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, T.

    1982-01-01

    In Japan eucalyptuses booms have occurred, the first boom from 1954 to 1959, the second boom from 1970 to 1976 and the third boom from 1979 to the present. At the first boom the fundamental studies on eucalyptuses were started by governmental funds. In Wakayama Prefecture eucalyptuses were planted over the area of 200 hectares by a private company. At the second boom Matusdo City made the plan in which the whole city would be planted with eucalyptuses, resulting in taking eucalyptus cultivation one step ahead. Both booms were closed by some failures. Third boom emerged from the necessity in energy. Eucalyptus oil contains cineol (C/sub 10/H/sub 18/O), one of monoterpenes. The practical test of eucalyptus oil and hypothesis of eucalyptus root are described. Water-hyacinth live on poor quality water.

  7. Simulation of pulp mill wastewater recycling after tertiary treatment.

    Science.gov (United States)

    Fontanier, V; Albet, J; Baig, S; Molinier, J

    2005-12-01

    The aim of this work is to study the possibilities of effluent recycling in a bleached Kraft pulp mill, for a better water management. To avoid problems associated with effluent recycling (corrosion, odors, loss in pulp and paper quality), wastewaters have to be treated before recycling. This study is particularly focused on organic matter removal. Several treatments are applied on a biological secondary effluent: adsorption on activated carbon, coagulation with ferric chloride or alum sulfate, precipitation with lime, ozonation and catalytic ozonation. These techniques are compared in terms of COD (Chemical Oxygen Demand) removal. Catalytic ozonation is finally chosen as the most effective solution to achieve 50% of COD removal in the effluent. The characteristics of the effluent treated according to this technique are then used to simulate the impact of its reuse in the process for pulp production. The study is focused on the changes in these parameters in the various stages of bleaching and final washing when water is replaced by the wastewater treated or directly issued from the wastewater treatment plant. The simulation demonstrates the need of a tertiary treatment to eliminate COD in order to avoid possible reactant overconsumption and decrease in pulp brightness. Chloride and sulfate ions which could cause corrosion should also be removed.

  8. Polyoxometalates in Oxidative Delignification of Chemical Pulps: Effect on Lignin

    Directory of Open Access Journals (Sweden)

    Kolby Hirth

    2010-03-01

    Full Text Available Chemical pulps are produced by chemical delignification of lignocelluloses such as wood or annual non-woody plants. After pulping (e.g., kraft pulping, the remaining lignin is removed by bleaching to produce a high quality, bright paper. The goal of bleaching is to remove lignin from the pulp without a negative effect on the cellulose; for this reason, delignification should be performed in a highly selective manner. New environmentally-friendly alternatives to conventional chlorine-based bleaching technologies (e.g., oxygen, ozone, or peroxide bleaching have been suggested or implemented. In an attempt to find inorganic agents that mimic the action of highly selective lignin-degrading enzymes and that can be applicable in industrial conditions, the researchers have focused on polyoxometalates (POMs, used either as regenerable redox reagents (in anaerobic conditions or as catalysts (in aerobic conditions of oxidative delignification. The aim of this paper is to review the basic concepts of POM delignification in these two processes.

  9. The influence of irradiation of gamma-rays on the pulping and paper making, (4)

    International Nuclear Information System (INIS)

    Suzuki, Kyoji; Inoue, Kaoru; Hanamura, Norio; Mori, Kenji

    1980-01-01

    The influence of gamma-irradiation on the beating properties of unbleached kraft pulps was studied, and the changes of the mechanical and chemical properties of the sheet made from those pulps were also investigated. The results obtained were as follows: (1) When the unbeaten pulp was treated with gamma-ray, the degree of polymerization of cellulose was decreased rapidly and the formation of aldehyde and carboxyl groups in pulp was observed in addition to that the beating time of irradiated pulps was reduced comparing with non-irradiated pulp. These effects increased roughly in proportion to the radiation dose. (2) Gamma-irradiation was more effective in wet state (moisture content = 70 - 80%) than air dry state. This may be due to the degradation products of water by gamma-irradiation. (3) The mechanical properties (breaking length, tear and burst factors) of the sheets made from irradiated pulps were considerably deteriorated at 10 7 R, but there was a slight deterioration up to 10 6 R. (4) Comparing the result of the mechanical properties, the strengths of the various sheets were shown in the following order: the sheet irradiated after paper making gt the sheet irradiated before beating (air dry state) gt the sheet irradiated before beating (wet state). (author)

  10. Biodegradation of kraft lignin by a bacterial strain Comamonas sp. B-9 isolated from eroded bamboo slips.

    Science.gov (United States)

    Chen, Y H; Chai, L Y; Zhu, Y H; Yang, Z H; Zheng, Y; Zhang, H

    2012-05-01

    The aim was to obtain evidences for lignin degradation by unicellular bacterium Comamonas sp. B-9. Comamonas sp. B-9 was inoculated into kraft lignin-mineral salt medium (KL-MSM) at pH 7·0 and 30°C for 7 days of incubation. The bacterial growth, chemical oxygen demand (COD) reduction, secretion of ligninolytic enzymes and productions of low-molecular-weight compounds revealed that Comamonas sp. B-9 was able to degrade kraft lignin (KL). COD in KL-MSM reduced by 32% after 7 days of incubation. The maximum activities of manganese peroxidase (MnP) of 2903·2 U l(-1) and laccase (Lac) of 1250 U l(-1) were observed at 4th and 6th day, respectively. The low-molecular-weight compounds such as ethanediol, 3, 5-dimethyl-benzaldehyde and phenethyl alcohol were formed in the degradation of KL by Comamonas sp. B-9 based on GC-MS analysis. This study confirmed that Comamonas sp. B-9 could utilize KL as a sole carbon source and degrade KL to low-molecular-weight compounds. Comamonas sp. B-9 may be useful in the utilization and bioconversion of lignin and lignin-derived aromatic compounds in biotechnological applications. Meanwhile, using Comamonas sp. B-9 in treatment of wastewater in pulp and paper industry is a meaningful work. © 2012 The Authors. Journal of Applied Microbiology © 2012 The Society for Applied Microbiology.

  11. Effect of eucalyptus (Eucalyptus camaldulensis) and maize (Zea ...

    African Journals Online (AJOL)

    soumare

    Editorial FAN, Bolivia. Soumare et al. 16001. Gareca EE, Martinez YY, Bustamante RO, Aguirre LF, Siles MM (2007). Regeneration patterns of Polylepis subtusalbida growing with the exotic trees Pinus radiata and Eucalyptus globulus at Parque. Nacional Tunari, Bolivia. Plant Ecol. 193:253-263. Hopkinsa AA, Malinowskic ...

  12. Drought and dieback of rural eucalypts. [Eucalyptus blakelyi; Eucalyptus melliodora

    Energy Technology Data Exchange (ETDEWEB)

    Landsberg, J.

    1985-01-01

    The possibility that drought causes dieback of eucalypts in rural Australia was investigated. Water potential and canopy condition in dieback and healthy rural Eucalyptus blakelyi and E. melliodora trees were compared during and after an extreme drought in the ACT. All the trees were drought affected, but the extent was independent of the condition of their canopies at the beginning of the study.

  13. A model system to study the lignification process in Eucalyptus globulus.

    Science.gov (United States)

    Araújo, Pedro; Cesarino, Igor; Mayer, Juliana Lischka Sampaio; Ferrari, Ilse Fernanda; Kiyota, Eduardo; Sawaya, Alexandra Christine Helena Frankland; Paes Leme, Adriana Franco; Mazzafera, Paulo

    2014-09-01

    Recalcitrance of plant biomass is closely related to the presence of the phenolic heteropolymer lignin in secondary cell walls, which has a negative effect on forage digestibility, biomass-to-biofuels conversion and chemical pulping. The genus Eucalyptus is the main source of wood for pulp and paper industry. However, when compared to model plants such as Arabidopsis thaliana and poplar, relatively little is known about lignin biosynthesis in Eucalyptus and only a few genes were functionally characterized. An efficient, fast and inexpensive in vitro system was developed to study lignification in Eucalyptus globulus and to evaluate the potential role of candidate genes in this biological process. Seedlings were grown in four different conditions, in the presence or absence of light and with or without sucrose in the growth medium, and several aspects of lignin metabolism were evaluated. Our results showed that light and, to a lesser extent, sucrose induced lignin biosynthesis, which was followed by changes in S/G ratio, lignin oligomers accumulation and gene expression. In addition, higher total peroxidase activity and differential isoperoxidase profile were observed when seedlings were grown in the presence of light and sucrose. Peptide sequencing allowed the identification of differentially expressed peroxidases, which can be considered potential candidate class III peroxidases involved in lignin polymerization in E. globulus. © 2014 Scandinavian Plant Physiology Society.

  14. Methods for facilitating microbial growth on pulp mill waste streams and characterization of the biodegradation potential of cultured microbes.

    Science.gov (United States)

    Mathews, Stephanie L; Ayoub, Ali S; Pawlak, Joel; Grunden, Amy M

    2013-12-12

    The kraft process is applied to wood chips for separation of lignin from the polysaccharides within lignocellulose for pulp that will produce a high quality paper. Black liquor is a pulping waste generated by the kraft process that has potential for downstream bioconversion. However, the recalcitrant nature of the lignocellulose resources, its chemical derivatives that constitute the majority of available organic carbon within black liquor, and its basic pH present challenges to microbial biodegradation of this waste material. Methods for the collection and modification of black liquor for microbial growth are aimed at utilization of this pulp waste to convert the lignin, organic acids, and polysaccharide degradation byproducts into valuable chemicals. The lignocellulose extraction techniques presented provide a reproducible method for preparation of lignocellulose growth substrates for understanding metabolic capacities of cultured microorganisms. Use of gas chromatography-mass spectrometry enables the identification and quantification of the fermentation products resulting from the growth of microorganisms on pulping waste. These methods when used together can facilitate the determination of the metabolic activity of microorganisms with potential to produce fermentation products that would provide greater value to the pulping system and reduce effluent waste, thereby increasing potential paper milling profits and offering additional uses for black liquor.

  15. Facilitating the enzymatic saccharification of pulped bamboo residues by degrading the remained xylan and lignin-carbohydrates complexes.

    Science.gov (United States)

    Huang, Caoxing; He, Juan; Li, Xin; Min, Douyong; Yong, Qiang

    2015-09-01

    Kraft pulping was performed on bamboo residues and its impact on the chemical compositions and the enzymatic digestibility of the samples were investigated. To improve the digestibility of sample by degrading the xylan and lignin-carbohydrates complexes (LCCs), xylanase and α-L-arabinofuranosidase (AF) were supplemented with cellulase. The results showed more carbohydrates were remained in the samples pulped with low effective alkali (EA) charge, compared to conventional kraft pulping. When 120 IU/g xylanase and 15 IU/g AF were supplemented with 20 FPU/g cellulase, the xylan degradation yield of the sample pulped with 12% EA charge increased from 68.20% to 88.35%, resulting in an increased enzymatic saccharification efficiency from 58.98% to 83.23%. The amount of LCCs in this sample decreased from 8.63/100C9 to 2.99/100C9 after saccharification with these enzymes. The results indicated that degrading the remained xylan and LCCs in the pulp could improve its enzymatic digestibility. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Microsatellite analysis of population structure in Eucalyptus globulus.

    Science.gov (United States)

    Costa, Joana; Vaillancourt, René E; Steane, Dorothy A; Jones, Rebecca C; Marques, Cristina

    2017-09-01

    Eucalyptus globulus subsp. globulus Labill. (Tasmanian Blue Gum), native to southeast Australia, is a benchmark species for the pulp and paper industry. We genotyped 397 trees from 16 populations of E. globulus representing the native diversity in Australia using 24 microsatellite loci. Eight genetically distinct groups were detected, consistent with genetic groupings detected in previous quantitative and molecular studies. A sample of 29 Portuguese individuals was added to help clarify the origin of the Portuguese landrace. The results suggest a southern and eastern Tasmania origin for the Portuguese landrace. This genetic framework will enable researchers to investigate the provenance of individuals of unknown pedigree and assess the levels of representation of E. globulus natural variation in the Portuguese landrace.

  17. Evaluation of bleached kraft mill process water using Microtox(R), Ceriodaphnia dubia, and Menidia beryllina toxicity tests.

    Science.gov (United States)

    Middaugh, D P; Beckham, N; Fournie, J W; Deardorff, T L

    1997-05-01

    To determine whether a 7- to 10-d embryo toxicity/teratogenicity test with the inland silverside fish, Menidia beryllina, is a sensitive indicator for evaluation of bleached kraft mill effluents, we compared this test with the Microtox(R) 15-min acute toxicity test and the Ceriodaphnia dubia 7-d chronic toxicity test. Water samples used in each test were collected from three areas in a bleached kraft pulp and paper mill using a 100% chlorine dioxide bleaching process: 1) river water prior to use in the mill; 2) the combined acid/base waste stream from the pulping process prior to biological treatment in the aerated stabilization basin (ASB); and 3) the effluent from the ASB with a retention time of approximately 11 d. Relative toxicity determined by the three tests for each water sampling location was compared. All three toxicity tests were predictive indicators of toxicity; however, the C. dubia and M. beryllina tests were the more similar and sensitive indicators of toxicity. Process water (ASB influent) prior to biological treatment in the ASB was toxic at all concentrations using the Microtox(R) and C. dubia tests. The fish embryo test showed no toxicity at 1% concentrations, slight toxicity at 10%, and acute toxicity at the 100% ASB influent concentration. Tests with biologically-treated ASB effluent indicated a substantial reduction in observed toxicity to Microtox(R) bacteria, C. dubia, and M. beryllina. No toxic responses were observed in any test at a 1% ASB effluent concentration which was the approximate effluent concentration in the receiving river following mixing. No relationship was found among any toxicological response and effluent levels of adsorbable organic halides, polychlorinated phenolic compounds, 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, total suspended solids, color, chemical oxygen demand, or total organic carbon.

  18. Electrochemical acidification of Kraft black liquor by electrodialysis with bipolar membrane: Ion exchange membrane fouling identification and mechanisms.

    Science.gov (United States)

    Haddad, Maryam; Mikhaylin, Sergey; Bazinet, Laurent; Savadogo, Oumarou; Paris, Jean

    2017-02-15

    Integrated forest biorefinery offers promising pathways to sustainably diversify the revenue of pulp and paper industry. In this context, lignin can be extracted from a residual stream of Kraft pulping process, called black liquor, and subsequently converted into a wide spectrum of bio-based products. Electrochemical acidification of Kraft black liquor by electrodialysis with bipolar membrane results in lignin extraction and caustic soda production. Even though the implementation of this method requires less chemicals than the chemical acidification process, fouling of the ion exchange membranes and especially bipolar membrane impairs its productivity. Membrane thickness and ash content measurements along with scanning electron microscopy (SEM), elemental analysis (EDX) and X-ray photoelectron spectrometry (XPS) analysis were performed to identify the nature and mechanisms of the membrane fouling. The results revealed that the fouling layer mostly consisted of organic components and particularly lignin. Based on our proposed fouling mechanisms, throughout the electrodialysis process the pH of the black liquor gradually decreased and as a result more proton ions were available to trigger protonation reaction of lignin phenolic groups and decrease the lignin solubility. Due to the abundance of the proton ions on the surface of the cation exchange layers of the bipolar membrane, destabilized lignin macro-molecules started to self-aggregate and formed lignin clusters on its surface. Over the time, these lignin clusters covered the entire surface of the bipolar membrane and the spaces between the membranes and, eventually, attached to the surface of the cation exchange membrane. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Ole Bjørn Kraft 1893-1980

    DEFF Research Database (Denmark)

    Skov, Christian Houlberg

    2010-01-01

    Ole Bjørn Kraft (1893-1980) var en central konservativ politiker i årene før og efter anden verdenskrig. Han markerede sig som udpræget idépolitiker og opnåede ad flere omgange at blive minister.......Ole Bjørn Kraft (1893-1980) var en central konservativ politiker i årene før og efter anden verdenskrig. Han markerede sig som udpræget idépolitiker og opnåede ad flere omgange at blive minister....

  20. ECONOMIC EVALUATION OF Eucalyptus grandis PLANTATION FOR CELLULOSE PRODUCTION

    Directory of Open Access Journals (Sweden)

    Antonio Donizette de Oliveira

    2008-03-01

    Full Text Available The aims of this research were: to analyze the economic feasibility of planting eucalyptus for producing wood pulp,considering various site index and two spacings; to analyze the economic effects regarding the profitability of the forest activity indifferent distances from the industry and changes on discount rate, wood price, transportation costs, minimum profitable diameter oflogs and the length of the logs. A biometric model for making wood volume prognosis was developed, using data of a trial ofEucalyptus grandis stands 19 and 103 months old. The prognosis started at the age zero, considering logs of 2.5 and 6.0 m of lenghtand the minimum diameter varying from 4 to 10 cm, in intervals of 2 cm. Net Present Worth (NPW was used as the economic decisioncriterium, considering an infinite horizon. The main conclusions were: reducing the minimum profitable diameter and the length ofthe logs are good strategies to increase wood utilization and profit; plantations located in less productive lands are economicallyunfeasible; the cost of transportation has significant effect on the profitability of the forest activity and must be analyzed carefully atthe moment of defining the location of new plantations; small variations on wood sales price may cause big alterations on theprofitability of the forest activity, suggesting that the improvement of the wood quality together with other decisions that may increasewood price are alternatives that may render the plantations in less productive areas profitable.

  1. Application of enzymes in the pulp and paper industry

    Science.gov (United States)

    Bajpai

    1999-03-01

    The pulp and paper industry processes huge quantities of lignocellulosic biomass every year. The technology for pulp manufacture is highly diverse, and numerous opportunities exist for the application of microbial enzymes. Historically, enzymes have found some uses in the paper industry, but these have been mainly confined to areas such as modifications of raw starch. However, a wide range of applications in the pulp and paper industry have now been identified. The use of enzymes in the pulp and paper industry has grown rapidly since the mid 1980s. While many applications of enzymes in the pulp and paper industry are still in the research and development stage, several applications have found their way into the mills in an unprecedented short period of time. Currently the most important application of enzymes is in the prebleaching of kraft pulp. Xylanase enzymes have been found to be most effective for that purpose. Xylanase prebleaching technology is now in use at several mills worldwide. This technology has been successfully transferred to full industrial scale in just a few years. The enzymatic pitch control method using lipase was put into practice in a large-scale paper-making process as a routine operation in the early 1990s and was the first case in the world in which an enzyme was successfully applied in the actual paper-making process. Improvement of pulp drainage with enzymes is practiced routinely at mill scale. Enzymatic deinking has also been successfully applied during mill trials and can be expected to expand in application as increasing amounts of newsprint must be deinked and recycled. The University of Georgia has recently opened a pilot plant for deinking of recycled paper. Pulp bleaching with a laccase mediator system has reached pilot plant stage and is expected to be commercialized soon. Enzymatic debarking, enzymatic beating, and reduction of vessel picking with enzymes are still in the R&D stage but hold great promise for reducing energy

  2. Species discrimination, population structure and linkage disequilibrium in Eucalyptus camaldulensis and Eucalyptus tereticornis using SSR markers.

    Directory of Open Access Journals (Sweden)

    Shanmugapriya Arumugasundaram

    Full Text Available Eucalyptus camaldulensis and E. tereticornis are closely related species commonly cultivated for pulp wood in many tropical countries including India. Understanding the genetic structure and linkage disequilibrium (LD existing in these species is essential for the improvement of industrially important traits. Our goal was to evaluate the use of simple sequence repeat (SSR loci for species discrimination, population structure and LD analysis in these species. Investigations were carried out with the most common alleles in 93 accessions belonging to these two species using 62 SSR markers through cross amplification. The polymorphic information content (PIC ranged from 0.44 to 0.93 and 0.36 to 0.93 in E. camaldulensis and E. tereticornis respectively. A clear delineation between the two species was evident based on the analysis of population structure and species-specific alleles. Significant genotypic LD was found in E. camaldulensis, wherein out of 135 significant pairs, 17 pairs showed r(2≥0.1. Similarly, in E. tereticornis, out of 136 significant pairs, 18 pairs showed r(2≥0.1. The extent of LD decayed rapidly showing the significance of association analyses in eucalypts with higher resolution markers. The availability of whole genome sequence for E. grandis and the synteny and co-linearity in the genome of eucalypts, will allow genome-wide genotyping using microsatellites or single nucleotide polymorphims.

  3. Effect of eucalyptus (Eucalyptus citriodora) fresh or residue leaves on methane emission in vitro

    OpenAIRE

    SALLAM, Sobhy M. A.; BUENO, Ives C. S.; NASSER, Mohamed E. A.; ABDALLA, Adibe L.

    2010-01-01

    Rumen fermentation and methane emission for eucalyptus (Eucalyptus citriodora) fresh leaves (FL) or residue leaves (RL), after essential oil extraction from eucalyptus leaves in comparison with alfalfa (Medicago sativa) hay, were investigated in vitro. Eucalyptus FL and RL were obtained from the Distillery Trees Barras Company, Torrinha City, Sao Paulo, Brazil. The semi-automatic system of gas production was used to measure gas production, methane emission and rumen fermentation after 24 h in...

  4. Combining ability of elite clones of Eucalyptus grandis and Eucalyptus urophylla with Eucalyptus globulus

    Directory of Open Access Journals (Sweden)

    Odair Bison

    2007-03-01

    Full Text Available In Brazil, eucalyptus breeding programs for cellulose production has used two species, Eucalyptus grandis and Eucalyptus urophylla. Nevertheless, it would be useful to introgress alleles from other species to improve wood quality and volume. The objective of this research was to evaluate the hybrid potential of elite clones of E. grandis and E. urophylla from the Aracruz Celulose Company S. A. with Eucalyptus globulus clones. To do so, six elite clones were crossed with ten E. globulus clones in a half-diallel mating design. The resulting hybrid combinations as well as the four check clones were evaluated in randomized complete block experiments with single plant plots and 40 replicates from September to October 2001 at three Brazilian sites, Aracruz and São Mateus in the Espírito Santo state and Caravelas in Bahia State. Two years later the circumference at breast height (CBH and the wood density (WD were measured. The means were submitted to diallel analysis according to the Griffing method (1956, adapted by Geraldi and Miranda Filho (1988. Although the number of clones involved was small, the crossings of elite clones of E. grandis and E. urophylla with clones of E. globulus were promising, especially for wood quality gains.

  5. Mycosphaerella and Teratosphaeria species associated with Mycosphaerella Leaf Disease on Eucalyptus globulus in Portugal

    Energy Technology Data Exchange (ETDEWEB)

    Silva, M. C.; Machado, H. N.; Neves, L.; Araujo, C.; Phillips, J. L.

    2012-11-01

    Plantations of Eucalyptus globulus represent the main source of wood for the pulp and paper industry in Portugal and are affected by the complex of Mycosphaerella and Teratosphaeria species (Mycosphaerella leaf disease), which is an important foliage disease worldwide. This disease affect mainly young trees with juvenile-phase foliage, causing premature defoliation, decreased growth and wood production. Species of Mycosphaerella sensu lato reported on eucalypts in Portugal are M. communis, M. heimii, M. lateralis, M. madeirae, M. marksii M. walkeri, T. africana, T. molleriana, T. nubilosa and T. parva. In order to complete the survey, symptomatic leaves were collected from Eucalyptus globulus plantations. Morphological and molecular characterization was used to give an indication of the species occurrence and most frequent species (T. nubilosa) and the composition of the MLD complex that did not change after the latest review. (Author) 28 refs.

  6. Rehe ja Kraft napsasid hiidudelt turuosa / Piret Reiljan

    Index Scriptorium Estoniae

    Reiljan, Piret, 1983-

    2007-01-01

    Nordea ja Sampo Pank on viimase aastaga uute ärilaenude mahtu kasvatanud 100 protsenti. Diagramm: Uute ärilaenudega esirinnas Nordea ja Sampo. Kommenteerivad: Priit Põldoja, Ahti Asmann, Aivar Rehe, Vahur Kraft ja Alo Lillepea. Vt. samas: Kodulaenude andmisel näpistab Sampo Ühispangalt turgu

  7. Võlakoorem tuhmistab Eesti võimalusi / Vahur Kraft

    Index Scriptorium Estoniae

    Kraft, Vahur, 1961-

    2003-01-01

    Eesti Panga president Vahur Kraft hoiatab liiga kergekäelise laenuvõtmise eest. Tema sõnul on Eesti Pank valmis vajaduse korral kasutama võimalusi nii laenuandjate kui ka -võtjate mõjutamiseks. Riigi stabiliseerimisreservist

  8. Recyclable zein-coated kraft paper and linerboard

    Science.gov (United States)

    Nicholas Parris; Marguerite Sykes; Leland C. Dickey; Jack L. Wiles; Thomas J. Urbanik; Peter H. Cooke

    2002-01-01

    Recyclability of kraft paper and linerboard coated with commercial zein and paraffin wax or a zein-lipid mixture was evaluated using conventional recycling processes. Zein, an alcohol-soluble protein from corn, exhibits both grease and water vapor barrier properties. Strength properties, grease resistance, and water vapor barrier proper-ties were measured on handsheets...

  9. Chemical composition of essential oils and hydrosols of three Eucalyptus species from Senegal: Eucalyptus alba Renv, Eucalyptus camaldulensis Dehnh and Eucalyptus tereticornis Hook

    OpenAIRE

    Barka Ndiaye, El Hadji; Talla Gueye, Momar; Ndiaye, Ibrahima; Diop, Serigne Mbacké; Diop, Michel Bakar; Fauconnier, Marie-Laure; Lognay, Georges

    2017-01-01

    The leaves of three eucalyptus species Eucalyptus Alba, Eucalyptus camaldulensis and ucalyptus tereticornis were collected in Kaolack (Senegal) and were extracted by steam distillation after 3, 7, 14 and 21 days of drying. The volatile components of aqueous distillates (hydrosols) were obtained by liquid–liquid extraction using n-hexane. The different extracts were analyzed by gas chromatography coupled to a flame ionization detector (GC-FID) and by gas chromatography coupled to a mass spe...

  10. Environmental assessment of different advanced oxidation processes applied to a bleaching Kraft mill effluent.

    Science.gov (United States)

    Muñoz, Iván; Rieradevall, Joan; Torrades, Francesc; Peral, José; Domènech, Xavier

    2006-01-01

    Different advanced oxidation processes (AOPs) have been applied to remove the organic carbon content of a paper mill effluent originating from the Kraft pulp bleaching process. The considered AOPs were: TiO(2)-mediated heterogeneous photocatalysis, TiO(2)-mediated heterogeneous photocatalysis assisted with H(2)O(2), TiO(2)-mediated heterogeneous photocatalysis coupled with Fenton, photo-Fenton, ozonation and ozonation with UV-A light irradiation. The application of the selected AOPs all resulted in a considerable decrease in dissolved organic carbon (DOC) content with variable treatment efficiencies depending upon the nature/type of the applied AOP. A Life Cycle Assessment (LCA) study was used as a tool to compare the different AOPs in terms of their environmental impact. Heterogeneous photocatalysis coupled with the Fenton's reagent proved to have the lowest environmental impact accompanied with a moderate-to-high DOC removal rate. On the other hand, heterogeneous photocatalysis appeared to be the worst AOP both in terms of DOC abatement rate and environmental impact. For the studied AOPs, LCA has indicated that the environmental impact was attributable to the high electrical energy (power) consumption necessary to run a UV-A lamp or to produce ozone.

  11. Remediation and toxicity removal from Kraft E1 paper mill effluent by ozonization.

    Science.gov (United States)

    Freire, R S; Kubota, L T; Durán, N

    2001-08-01

    The degradation of Kraft E1 pulp mill effluent was studied by four different ozonization oxidation systems (O3/pH3, O3/pH11, O3/pH11/H2O2, O3/pH11/UV). The investigation was focused on the reduction of total organic carbon (TOC), total phenols, color and acute toxicity (monitoring by inhibition of Escherichia coli respiration). For a reaction time of 90 minutes, the O3/pH11/UV was the most effective process for decoloration (45%). The O3/pH11/H2O2, O3/pH11/UV and O3/pH11 processes showed the best results for total phenols reduction (approximately/= 90%). None of the studied processes showed a significant TOC reduction. The O3/pH11/UV and O3/pH11 processes were effective for the acute toxicity reduction. Different kinetic parameters were also determined in order to quantify the reactivity of the effluent towards the applied oxidation systems.

  12. Biofilms from micro/nanocellulose of NaBH4-modified kraft pulp

    Indian Academy of Sciences (India)

    2017-07-26

    Jul 26, 2017 ... The complex structure of lignocellulosic biomass is the main obstacle in fractionating cellulose, which is organized into fibrils in the structure. The fibrils are aligned parallel to each other and surrounded by a matrix of lignin and hemi- celluloses. The lignin limits cell permeability and causes insignificant cell ...

  13. Biofilms from micro/nanocellulose of NaBH4-modified kraft pulp

    Indian Academy of Sciences (India)

    2017-07-26

    Jul 26, 2017 ... (figure 2). Some minor chemical shifts observed could be attributed to the packing effect of the supramolecular structures due to different chemical reactions and physical processings [46]. C4 peaks give insights about crystalline and non-crystalline forms. They were obtained as doubled- collateral peaks at ...

  14. Jüri Kraft : Eesti eksport nõuab Euroopa Liitu minekut / Jüri Kraft ; interv. Sulev Oll

    Index Scriptorium Estoniae

    Kraft, Jüri, 1935-

    2003-01-01

    Kahe kergetööstusettevõtte, Sangari ja Mivari nõukogu esimees, endine ENSV kergetööstusminister Jüri Kraft leiab, et kui Eesti ei astu EL-i ja loobub soodsast ekspordivõimalusest, kordub Eestis 1990. aastate alguse olukord

  15. Paper Pulp Panoply.

    Science.gov (United States)

    Marque, Margo E.

    1999-01-01

    Explains that creating paper-pulp bowls is designed to acquaint students with the beginning vocabulary and finger dexterity needed to sculpt clay. Describes the process of making paper-pulp bowls and identifies important vocabulary words. Provides directions for making paper bowl forms and lists the materials. (CMK)

  16. Breeding Eucalyptus for disease resistance

    Science.gov (United States)

    Edival A.V. Zauza; Acelino Couto Alfenas; Lúcio Mauro da Silva Guimarães; João Flávio da Silva

    2012-01-01

    Eucalyptus plantations cover about 1.5 percent of the agricultural area in Brazil, and contribute to 4 percent of GDP and 3 percent in exports of forest products. Technological and research advances in silviculture and genetic improvement have increased productivity up to 80 m³ of wood/ha/year, with an average of 35 to 45 m³/ha/year. The greatest...

  17. [Effects of introducing Eucalyptus on indigenous biodiversity].

    Science.gov (United States)

    Ping, Liang; Xie, Zong-Qiang

    2009-07-01

    Eucalyptus is well-known as an effective reforestation tree species, due to its fast growth and high adaptability to various environments. However, the introduction of Eucalyptus could have negative effects on the local environment, e. g., inducing soil degradation, decline of groundwater level, and decrease of biodiversity, and especially, there still have controversies on the effects of introduced Eucalyptus on the understory biodiversity of indigenous plant communities and related mechanisms. Based on a detailed analysis of the literatures at home and abroad, it was considered that the indigenous plant species in the majority of introduced Eucalyptus plantations were lesser than those in natural forests and indigenous species plantations but more than those in other exotic species plantations, mainly due to the unique eco-physiological characteristics of Eucalyptus and the irrational plantation design and harvesting techniques, among which, anthropogenic factors played leading roles. Be that as it may, the negative effects of introducing Eucalyptus on local plant biodiversity could be minimized via more rigorous scientific plantation design and management based on local plant community characteristics. To mitigate the negative effects of Eucalyptus introduction, the native trees and understory vegetation in plantations should be kept intact during reforestation with Eucalyptus to favor the normal development of plant community and regeneration. At the same time, human disturbance should be minimized to facilitate the natural regeneration of native species.

  18. Early selection of Eucalyptus clones in retrospective nursery test ...

    African Journals Online (AJOL)

    Within the framework of the eucalyptus breeding programme in the Congo, two retrospective tests were conducted using mature clones in the field and young cuttings under nursery conditions with two hybrids: 13 clones of Eucalyptus tereticornis* Eucalyptus grandis for the test TC 82-1B and 17 clones of Eucalyptus ...

  19. Natural radionuclides in an eucalyptus forest located in the south of Spain

    International Nuclear Information System (INIS)

    Vaca, F.; Manjon, G.; Garcia-Leon, M.

    2001-01-01

    Eucalyptus forests can be considered as the main source of raw material for the pulp industry of Spain. This environment was selected for a radioactivity study because natural and artificial radionuclides can be transferred into the pulp mills, associated with raw material, wood and barks, where they are concentrated by industrial processes, becoming a cause of doses. Radionuclide concentration of natural radionuclides ( 238 U, 234 U, 228 Th, 230 Th, 232 Th) were determined by alpha- and gamma-spectrometry. Well-established radiochemical procedures were applied to environmental samples in order to isolate these radionuclides. A comparison between 228 Th activity, determined by gamma-spectrometry, and 232 Th activity, determined by alpha-spectrometry, was used as quality control parameter for analyses. The concentration factors were finally evaluated from experimental data.

  20. Properties of OCC Pulp

    Directory of Open Access Journals (Sweden)

    Masoumeh Moradi

    2013-06-01

    Full Text Available Old Corrugated Container (OCC recycled pulp provided by a local paper manufacturing company was treated by lactase enzyme. The pulp was sampled from headbox and treated by enzyme in the conditions of consistency 2%, pH 5, reaction time 2 hours, and reaction temperature 60 °C in dosing levels of 0.005, 0.01 and 0.015 % based on oven-dried weight of pulp. Fiber classification of the control pulp showed 31.3 % of fines content and 0.82 mm average fiber length. Results have indicated that lactase treatment decreased kappa number and SR degree to 20% and 14 degrees, respectively which consequently facilitated the drainage of pulp. The extraction of treated samples showed a peak at around 280 nm, confirming the delignification of pulp by enzyme. Microscopic observation of fiber walls of the treated sample indicated a local separation of middle lamella, fiber linting and removal of fines from fiber surface. The highest Water Retention Value (WRV was measured to be at 0.015% enzyme addition level. The apparent density of handsheets made from treated samples was lower compared with the handsheets made of control pulp resulting in loss of paper strengths.

  1. Mill Integration-Pulping, Stream Reforming and Direct Causticization for Black Liquor Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Adriaan van Heiningen

    2007-06-30

    MTCI/StoneChem developed a steam reforming, fluidized bed gasification technology for biomass. DOE supported the demonstration of this technology for gasification of spent wood pulping liquor (or 'black liquor') at Georgia-Pacific's Big Island, Virginia mill. The present pre-commercial R&D project addressed the opportunities as well as identified negative aspects when the MTCI/StoneChem gasification technology is integrated in a pulp mill production facility. The opportunities arise because black liquor gasification produces sulfur (as H{sub 2}S) and sodium (as Na{sub 2}CO{sub 3}) in separate streams which may be used beneficially for improved pulp yield and properties. The negative aspect of kraft black liquor gasification is that the amount of Na{sub 2}CO{sub 3} which must be converted to NaOH (the so called causticizing requirement) is increased. This arises because sulfur is released as Na{sub 2}S during conventional kraft black liquor recovery, while during gasification the sodium associated Na{sub 2}S is partly or fully converted to Na{sub 2}CO{sub 3}. The causticizing requirement can be eliminated by including a TiO{sub 2} based cyclic process called direct causticization. In this process black liquor is gasified in the presence of (low sodium content) titanates which convert Na{sub 2}CO{sub 3} to (high sodium content) titanates. NaOH is formed when contacting the latter titanates with water, thereby eliminating the causticizing requirement entirely. The leached and low sodium titanates are returned to the gasification process. The project team comprised the University of Maine (UM), North Carolina State University (NCSU) and MTCI/ThermoChem. NCSU and MTCI are subcontractors to UM. The principal organization for the contract is UM. NCSU investigated the techno-economics of using advanced pulping techniques which fully utilize the unique cooking liquors produced by steam reforming of black liquor (Task 1). UM studied the kinetics and

  2. Advancing Eucalyptus Genomics: Cytogenomics Reveals Conservation of Eucalyptus Genomes

    Science.gov (United States)

    Ribeiro, Teresa; Barrela, Ricardo M.; Bergès, Hélène; Marques, Cristina; Loureiro, João; Morais-Cecílio, Leonor; Paiva, Jorge A. P.

    2016-01-01

    The genus Eucalyptus encloses several species with high ecological and economic value, being the subgenus Symphyomyrtus one of the most important. Species such as E. grandis and E. globulus are well characterized at the molecular level but knowledge regarding genome and chromosome organization is very scarce. Here we characterized and compared the karyotypes of three economically important species, E. grandis, E. globulus, and E. calmadulensis, and three with ecological relevance, E. pulverulenta, E. cornuta, and E. occidentalis, through an integrative approach including genome size estimation, fluorochrome banding, rDNA FISH, and BAC landing comprising genes involved in lignin biosynthesis. All karyotypes show a high degree of conservation with pericentromeric 35S and 5S rDNA loci in the first and third pairs, respectively. GC-rich heterochromatin was restricted to the 35S rDNA locus while the AT-rich heterochromatin pattern was species-specific. The slight differences in karyotype formulas and distribution of AT-rich heterochromatin, along with genome sizes estimations, support the idea of Eucalyptus genome evolution by local expansions of heterochromatin clusters. The unusual co-localization of both rDNA with AT-rich heterochromatin was attributed mainly to the presence of silent transposable elements in those loci. The cinnamoyl CoA reductase gene (CCR1) previously assessed to linkage group 10 (LG10) was clearly localized distally at the long arm of chromosome 9 establishing an unexpected correlation between the cytogenetic chromosome 9 and the LG10. Our work is novel and contributes to the understanding of Eucalyptus genome organization which is essential to develop successful advanced breeding strategies for this genus. PMID:27148332

  3. Effect of eucalyptus (Eucalyptus citriodora fresh or residue leaves on methane emission in vitro

    Directory of Open Access Journals (Sweden)

    Adibe L. Abdalla

    2010-09-01

    Full Text Available Rumen fermentation and methane emission for eucalyptus (Eucalyptus citriodora fresh leaves (FL or residue leaves (RL, after essential oil extraction from eucalyptus leaves in comparison with alfalfa (Medicago sativa hay, were investigated in vitro. Eucalyptus FL and RL were obtained from the Distillery Trees Barras Company, Torrinha City, Sao Paulo, Brazil. The semi-automatic system of gas production was used to measure gas production, methane emission and rumen fermentation after 24 h incubation in vitro. The results showed that the crude protein (CP contents were 76.4, 78.1 and 181.9 g kg-1 DM for eucalyptus FL, RL and alfalfa hay, respectively. The neutral-detergent fibre (NDF and acid-detergent fibre (ADF were significantly lower in eucalyptus FL and RL than alfalfa hay. The Eucalyptus fresh and residue leaves were rich in total phenols (TP and total tannins (TT but had negligible content of condensed tannins (CT. There was significant reduction in cumulative gas production about 54 and 51% with eucalyptus FL and RL, respectively, compared with alfalfa hay. The methane emission (mL/g DM was reduced (P<0.05 by 53 and 57% with eucalyptus FL and RL, respectively, but the reduction was 21 and 16% when expressed on truly digested organic matter basis. There were a decline (P<0.05 in true dry and organic matter degradation in vitro in eucalyptus FL and RL compared with alfalfa hay substrate. The partitioning factor values were higher (P<0.05 in eucalyptus FL and RL than alfalfa hay. There was no significant difference observed between eucalyptus FL, RL and alfalfa hay in protozoa count. It is concluded that the eucalyptus leaves have potential effect to mitigate CH4 production in vitro, which may be attributed to a decrease in fermentable substrate rather than to a direct effect on methanogenesis.

  4. The effect of chemical composition on microfibrillar cellulose films from wood pulps: mechanical processing and physical properties.

    Science.gov (United States)

    Spence, Kelley L; Venditti, Richard A; Habibi, Youssef; Rojas, Orlando J; Pawlak, Joel J

    2010-08-01

    Films of microfibrillated celluloses (MFCs) from pulps of different yields, containing varying amounts of extractives, lignin, and hemicelluloses, were produced by combining refining and high-pressure homogenization techniques. MFC films were produced using a casting-evaporation technique and the physical and mechanical properties (including density, roughness, fold endurance and tensile properties) were determined. Homogenization of bleached and unbleached Kraft pulps gave rise to highly individualized MFCs, but not for thermo-mechanical pulp (TMP). The resulting MFC films had a roughness equivalent to the surface upon which the films were cast. Interestingly, after homogenization, the presence of lignin significantly increased film toughness, tensile index, and elastic modulus. The hornification of fibers through a drying and rewetting cycle prior to refining and homogenization did not produce any significant effect compared to films from never-dried fibers, indicating that MFC films can potentially be made from low-cost recycled cellulosic materials. (c) 2010 Elsevier Ltd. All rights reserved.

  5. Mergers and acquisitions : the case of Kraft Foods and Cadbury

    OpenAIRE

    Ribeiro, Sara Isabel de Paula

    2013-01-01

    The aim of this dissertation is to focus on a determinant aspect of Corporate Finance that is Mergers and Acquisitions (M&A). This dissertation not only provides a practical analysis of main issued regarding a process of M&A, but also provides a theoretical framework about M&A. Specifically, this dissertation explores the real case of Kraft Foods - world’s second largest manufacturer and packager food products – and Cadbury - the world’s second largest confectionery firm. ...

  6. A comprehensive program to develop correlations for the physical properties of Kraft black liquor. Interim report No. 2

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, A.L.

    1990-12-01

    Experimental effort for the program to evaluate physical properties of kraft black liquors is now proceeding well. Experimental work includes pulping, liquor analysis, lignin purification and characterization, vapor-liquid equilibria, heat capacity, heats of solution and combustion, and viscosity measurements. Measurement of thermal conductivity has not yet begun. Collection of the data necessary for development of generalized correlations is proceeding, but will require about two more years. The digester is operating very well. It is now possible to operate the digester as a closed, rotating reactor or as a batch reactor with liquor circulation. When operated with liquor circulation, temperatures within the chip bed can be monitored during cooking. Cooking is reproducible, and cooks are being performed to produce liquors for experimental studies. The digester could be further modified to permit us to conduct rapid exchange batch pulping or to permit us to simulate continuous pulping. Liquors to be used in experimental studies are concentrated in our large scale evaporator or in our small scale evaporator. The large scale evaporator is used to concentrate liquors to about 50% solids for storage and for use in studies requiring high solids liquors. The small scale evaporator is used for preparing final samples to as high as 85% solids and for measuring vapor-liquid equilibria. Liquors are now routinely analyzed to determine all components, except higher molecular weight organic acids and extractives. Lignin determination by uv-visible means has been improved. Lignin purification from black liquor has been improved and lignin molecular weights are determined routinely. Work on lignin molecular weight distribution is still not satisfactory, but recent developments holds promise.

  7. Internationalisation; KonKraft-rapport 4; Internasjonalisering

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    disintegrate. The obvious strategy to pursuit is to strengthen Norway's position as a dynamic and leading competence center for oil- and gas activities. Recruitment and development of sufficient competencies is generally a major challenge for the oil- and gas trade. Shortage of human capital leads to increased wage pressure which in the long run may weaken profits and competitiveness. In some of the petroleum clusters the companies try to find solutions to counteract the negative effects of the battle for the best brains. Through the project KonKraft INTSOK has unveiled high ambitions concerning increased internationalisation throughout the Norwegian petroleum cluster, except for Northern Norway. Here there is still an opposition against activities in the region, as well as in the Barents sea. INTSOK's intention with the project has been to describe its multitude. Therefore eight very different environments where selected to make a closer study on the development in different regions. The environments represent a variety of sizes, geography and trades. Some of the clusters are new or under establishment, others are already in full operation. Together the eight environments cover a major part of the value chain in the Norwegian offshore sector. The project has clearly demonstrated that cluster development contributes both to internationalisation as well as keeping the companies in Norway. Some main findings: The positive development in the drilling cluster of Southern Norway - the Node cluster - has created strong impact: The cluster ranks among the world's leading on drilling equipment and barely any oil or gas environment has had a similar expansion. The Kongsberg environment is not an offshore cluster, but an overall technology cluster where offshore applications is one of several technology areas. The companies develop and produce a broad range of advanced products and systems. The turnover among the offshore companies amounts to 65% of the total turnover for

  8. Physical properties of kraft black liquor. Final report. Phase I

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, A.L.

    1983-12-01

    Methods were selected, equipment installed, and procedures developed for determining rheological properties; for determining thermal properties (stability, density, thermal expansion, and heat capacity); for purification and characterization of lignin (glass transition, stability, weight average molecular weight, and number average molecular weight); and for performing chemical analyses (negative inorganic ions, positive inorganic ions, acid organic salts, lignin, and total solids). A strategy for pulping to supply test liquors was developed, and a statistically designed pulping experiment was specified for a Southern softwood species. Arrangements were made for performing initial pulping work in an industrial pilot plant, and a preliminary set of pulping experiments were conducted. Liquors from the preliminary pulping experiments were used to test procedures and to determine reproducibility of the experiment. Literature was also surveyed and preliminary selection of designs for a pilot digester, and for equipment to determine surface tension were made.

  9. Photosynthetic temperature responses of Eucalyptus globulus and Eucalyptus nitens

    Energy Technology Data Exchange (ETDEWEB)

    Battaglia, M.; Beadle, C. [Commonwealth Scientific and Industrial Research Organization (CSIRO), Canberra, ACT (Australia). Div. of Forestry and Forest Products; Loughead, S. [Tasmania Univ., Hobart, TAS (Australia)

    1996-01-01

    Photosynthetic responses to temperature variations of four year old Eucalyptus globulus and Eucalyptus nitens were investigated. Temperatures varied between 10 degrees C and 35 degrees C, and were measured at approximately monthly intervals from early spring until midwinter. The photosynthetic temperature optimum was found to be linearly related to the average temperature of the preceding week during the entire nine month period. For E. globulus the optimum temperature for net photosynthesis increased from 17 degrees C to 23 degrees C as the mean daily temperature increased from 7 degrees C to 16 degrees. The corresponding values for E. nitens were 14 to 20 degrees C as the mean daily temperature increased from 7 to 19 degrees C. The photosynthetic performance of E. nitens was less sensitive to temperatures above and below the optimum than E. globulus. In a second experiment E. globulus clones were acclimated in temperature-controlled greenhouses, and in a shadehouse in four climatically different regions of Tasmania. A comparison of light response curves of the plants showed that the maximum rate of net photosynthesis was affected by the growth temperature, whereas apparent quantum efficiency remained unchanged. 25 refs., 3 tabs., 8 figs.

  10. Genetic transformation of Eucalyptus camaldulensis by agrobalistic method

    Directory of Open Access Journals (Sweden)

    Evânia Galvão Mendonça

    2013-06-01

    Full Text Available Eucalyptus stands in the setting of worldwide forestry due to its adaptability, rapid growth, production of high-quality and low cost of wood pulp fibers. The eucalyptus convetional breeding is impaired mainlly by the long life cycle making the genetic transformation systems an important tool for this purpose. However, this system requires in vitro eficient protocols for plant induction, regeneration and seletion, that allow to obtain transgenic plants from the transformed cell groups. The aim of this work was to evaluate the callus formation and to optimize the leaves and callus genetic transformation protocol by using the Agrobacterium tumefaciens system. Concerning callus formation, two different culture media were evaluated: MS medium supplemented with auxin, cytokinin (M1 and the MS medium with reduced nitrogen concentration and supplemented with auxin, cytokinin coconut water (M2. To establish the leave genetic transformation, those were exposed to agrobiolistics technique (gene gun, to tissue injury, and A. tumesfasciens EHA 105 contening the vetor pCambia 3301 (35S::GUS::NOS, for gene transference and to establish the callus transformation thoses were exposed only to A. tumefasciens. For both experiments, the influence of different infection periods was evaluated. The M2 medium provided the best values for callus sizea and fresh and dry weight. The leaves genetic transformation using the agrobiolistics technique was effective, the gus gene transient expression could be observed. No significant differences were obtained in the infection periods (4, 6 and 8 minutes. The callus genetic transformation with A. tumefaciens also promotend the gus gene transient expression on the callus co-cultiveted for 15 e 30 minutes. The transformed callus was transfered to a regeneration and selection medium and transformed plants were obtained.

  11. Eucalyptus globulus (eucalyptus) treatment of candidiasis in normal and diabetic rats.

    Science.gov (United States)

    Bokaeian, Mohammad; Nakhaee, Alireza; Moodi, Bita; Ali Khazaei, Hossein

    2010-07-01

    The leaves of Eucalyptus globulus (eucalyptus) are used for treatment of diabetes mellitus in traditional medicine. The aim of this study was to evaluate the effects of eucalyptus in treatment of established systemic infection with Candida albicans in normal and streptozotocin-induced diabetic rats. Sixty normoglycemic male Wistar rats, weighing 200-250 g, were selected and randomly divided into six groups (n= 10): normal control, control + C. albicans, control + eucalyptus + C. albicans, diabetic control, diabetic + C. albicans, diabetic + eucalyptus + C. albicans. Diabetes was induced after a single intraperitoneal injection of streptozotocin (60 mg/kg body weight) and eucalyptus was added to the diet (62.5 g/kg) and drinking water (2.5 g/L) of treated animals for 4 weeks. The concerned groups were inoculated with C. albicans 15 days after diabetes induction. At the end of one month experiment, fasted rats were killed by cervical decapitation. Blood was collected from neck vein for estimation of glucose. C. albicans concentrations were estimated in liver and kidneys using serial dilution culture of tissue homogenates. Eucalyptus administration significantly improved the hyperglycemia, polydipsia, polyphagia, and it also compensated weight loss of diabetic rats (P less than 0.05). Moreover, eucalyptus caused a significant reduction in C. albicans concentration in liver and kidney homogenates (P less than 0.01). The results revealed that eucalyptus improves Candidia infection in normal and diabetic rats that in some ways validates the traditional use of this plant in treatment of diabetic patients.

  12. Cryopreservation of eucalyptus genetic resources.

    Science.gov (United States)

    Kaya, E; Alves, A; Rodrigues, L; Jenderek, M; Hernandez-Ellis, M; Ozudogru, A; Ellis, D

    2013-01-01

    The long-term preservation of forest genetic resources is a vital part of preserving our forest crops for future generations. Unfortunately, there are few genebanks dedicated to forest trees and very few methods for long-term preservation of forest genetic resources collections aside from field plantings of a limited number of seed-derived or elite clonal individuals. The use of cryopreservation for the long-term storage of elite germplasm is increasingly being used for the long-term preservation of clonal agronomic crops but for forest trees, such as Eucalyptus, the methodology for cryopreservation of diverse genetic resources collections has not been established. We report the successful cryopreservation of a germplasm collection of in vitro shoot cultures of thirteen Eucalyptus spp. lines consisting of two E. grandis x E. camaldulensis lines, seven E. urophylla x E. grandis lines, one E. grandis line, two E. grandis x E. urophylla lines, and one E. camaldulensis line. In a comparison of two cryopreservation methods, sucrose sensitivity limited the application of encapsulation-dehydration. However, with droplet-vitrification, all thirteen lines had good survival after cryopreservation in liquid nitrogen. A 30 min exposure to Plant Vitrification Solution 2 (PVS2) yielded post-liquid nitrogen survival between 38% and 85% depending on the line. One hundred shoot tips from all thirteen lines are currently in long-term storage as a germplasm collection.

  13. Preparation of lumen-loaded kenaf pulp with magnetite (Fe{sub 3}O{sub 4})

    Energy Technology Data Exchange (ETDEWEB)

    Zakaria, S.; Ong, B.H.; Ahmad, S.H.; Abdullah, M.; Yamauchi, T

    2005-02-15

    Magnetic pulps were prepared from unbleached kenaf (hibiscus cannabinus L.) kraft pulps. Fe{sub 3}O{sub 4} or magnetite powder was used to load into the pulp's lumen and pit. Aluminum sulphate [Al{sub 2}(SO{sub 4}){sub 3}] (alum) and polyethylenimine (PEI), both mainly function as retention aid were used throughout the experiment and found to be beneficial in the preparation of this magnetic pulps. The ash content method was used to determine the amount of magnetite retained in the lumen and pit. The utilization of PEI up to 2% per pulp fibres was found to be the best result on lumen loading. The deposition of magnetite powder in lumen and pit is found decrease as the addition of PEI used is more than 2% per pulp fibres. Scanning electron microscope (SEM) clearly shows the distribution of magnetite deposited in the lumen. Tensile index and folding endurance of the loaded fibre decreased slightly as the percentage of loading pigment increased.

  14. Utilization of softwood kraft lignin as adhsive for the manufacture of reconstituted wood

    Science.gov (United States)

    Lin-Wu Zhao; Bruce F. Griggs; Chen-Loung Chen; Josef S. Gratzl; Chung-Yun Hse

    1994-01-01

    Reaction conditions for hydroxymethylation of pine kraft lignin (KL) were optimized by kinetic studies of the reaction. Characterization of the resulting hydroxymethylated kraft lignin (HMKL) indicated that about 0.36 mole of the -CH2OH/C9 unit was introduced into the ognin under the optimal reaction conditions, of which...

  15. Precipitation and valorisation of lignin obtained from South African Kraft mill black liquor

    CSIR Research Space (South Africa)

    Namane, Mpho

    2016-04-01

    Full Text Available . In this thesis, the isolation and recovery of lignin from kraft mill black liquor was examined, an in-depth characterisation of the polymer was undertaken, and finally, a method for the potential valorisation of the lignin from a South African kraft mill...

  16. HIGHLY ENERGY EFFICIENT D-GLU (DIRECTED-GREEN LIQ-UOR UTILIZATION) PULPING

    Energy Technology Data Exchange (ETDEWEB)

    Lucia, Lucian A

    2013-04-19

    Purpose: The purpose of the project was to retrofit the front end (pulp house) of a commercial kraft pulping mill to accommodate a mill green liquor (GL) impregna-tion/soak/exposure and accrue downstream physical and chemical benefits while prin-cipally reducing the energy footprint of the mill. A major player in the mill contrib-uting to excessive energy costs is the lime kiln. The project was intended to offload the energy (oil or natural gas) demands of the kiln by by-passing the causticization/slaking site in the recovery area and directly using green liquor as a pulping medium for wood. Scope: The project was run in two distinct, yet mutually compatible, phases: Phase 1 was the pre-commercial or laboratory phase in which NC State University and the Insti-tute of Paper Science and Technology (at the Georgia Institute of Technology) ran the pulping and associated experiments, while Phase 2 was the mill scale trial. The first tri-al was run at the now defunct Evergreen Pulp Mill in Samoa, CA and lead to a partial retrofit of the mill that was not completed because it went bankrupt and the work was no longer the low-hanging fruit on the tree for the new management. The second trial was run at the MeadWestvaco Pulp Mill in Evedale, TX which for all intents and pur-poses was a success. They were able to fully retrofit the mill, ran the trial, studied the pulp properties, and gave us conclusions.

  17. Production of cellulase from kraft paper mill sludge by Trichoderma reesei rut C-30.

    Science.gov (United States)

    Wang, Wei; Kang, Li; Lee, Yoon Y

    2010-05-01

    Paper mill sludge is a solid waste material generated from pulping and papermaking operations. Because of high glucan content and its well-dispersed structure, paper mill sludges are well suited for bioconversion into value-added products. It also has high ash content originated from inorganic additives used in papermaking, which causes hindrance to bioconversion. In this study, paper mill sludges from Kraft process were de-ashed by a centrifugal cleaner and successive treatment by sulfuric acid and sodium hydroxide, and used as a substrate for cellulase production. The treated sludge was the only carbon source for cellulase production, and predominantly inorganic nutrients were used as the nitrogen source for this bioprocess. The cellulase enzyme produced from the de-ashed sludge exhibited cellulase activity of 8 filter paper unit (FPU)/mL, close to that obtainable from pure cellulosic substrates. The yield of cellulase enzyme was 307 FPU/g glucan of de-ashed sludge. Specific activity was 8.0 FPU/mg protein. In activity tests conducted against the corn stover and alpha-cellulose, the xylanse activity was found to be higher than that of a commercial cellulase. Relatively high xylan content in the sludge appears to have induced high xylanase production. Simultaneous saccharification and fermentation (SSF) was performed using partially de-ashed sludge as the feedstock for ethanol production using Sacharomyces cerevisiae and the cellulase produced in-house from the sludge. With 6% (w/v) glucan feed, ethanol yield of 72% of theoretical maximum and 24.4 g/L ethanol concentration were achieved. These results were identical to those of the SSF using commercial cellulases.

  18. Decellularized Swine Dental Pulp as a Bioscaffold for Pulp Regeneration

    Directory of Open Access Journals (Sweden)

    Lei Hu

    2017-01-01

    Full Text Available Endodontic regeneration shows promise in treating dental pulp diseases; however, no suitable scaffolds exist for pulp regeneration. Acellular natural extracellular matrix (ECM is a favorable scaffold for tissue regeneration since the anatomical structure and ECM of the natural tissues or organs are well-preserved. Xenogeneic ECM is superior to autologous or allogeneic ECM in tissue engineering for its unlimited resources. This study investigated the characteristics of decellularized dental pulp ECM from swine and evaluated whether it could mediate pulp regeneration. Dental pulps were acquired from the mandible anterior teeth of swine 12 months of age and decellularized with 10% sodium dodecyl sulfate (SDS combined with Triton X-100. Pulp regeneration was conducted by seeding human dental pulp stem cells into decellularized pulp and transplanted subcutaneously into nude mice for 8 weeks. The decellularized pulp demonstrated preserved natural shape and structure without any cellular components. Histological analysis showed excellent ECM preservation and pulp-like tissue, and newly formed mineralized tissues were regenerated after being transplanted in vivo. In conclusion, decellularized swine dental pulp maintains ECM components favoring stem cell proliferation and differentiation, thus representing a suitable scaffold for improving clinical outcomes and functions of teeth with dental pulp diseases.

  19. Decellularized Swine Dental Pulp as a Bioscaffold for Pulp Regeneration.

    Science.gov (United States)

    Hu, Lei; Gao, Zhenhua; Xu, Junji; Zhu, Zhao; Fan, Zhipeng; Zhang, Chunmei; Wang, Jinsong; Wang, Songlin

    2017-01-01

    Endodontic regeneration shows promise in treating dental pulp diseases; however, no suitable scaffolds exist for pulp regeneration. Acellular natural extracellular matrix (ECM) is a favorable scaffold for tissue regeneration since the anatomical structure and ECM of the natural tissues or organs are well-preserved. Xenogeneic ECM is superior to autologous or allogeneic ECM in tissue engineering for its unlimited resources. This study investigated the characteristics of decellularized dental pulp ECM from swine and evaluated whether it could mediate pulp regeneration. Dental pulps were acquired from the mandible anterior teeth of swine 12 months of age and decellularized with 10% sodium dodecyl sulfate (SDS) combined with Triton X-100. Pulp regeneration was conducted by seeding human dental pulp stem cells into decellularized pulp and transplanted subcutaneously into nude mice for 8 weeks. The decellularized pulp demonstrated preserved natural shape and structure without any cellular components. Histological analysis showed excellent ECM preservation and pulp-like tissue, and newly formed mineralized tissues were regenerated after being transplanted in vivo. In conclusion, decellularized swine dental pulp maintains ECM components favoring stem cell proliferation and differentiation, thus representing a suitable scaffold for improving clinical outcomes and functions of teeth with dental pulp diseases.

  20. Marker-assisted selection in Eucalyptus

    International Nuclear Information System (INIS)

    Grattapaglia, D.

    2007-01-01

    Planted Eucalyptus occupies globally more than 18 million hectares and has become the most widely planted hardwood tree in the world, supplying high-quality woody biomass for several industrial applications. In this chapter an overview is presented on the status and perspectives of marker-assisted selection (MAS) in species of Eucalyptus. After an introduction to the main features of modern eucalypt breeding and clonal forestry, some applications of molecular markers in support to operational breeding are presented. By reviewing the status of quantitative trait locus (QTL) mapping in Eucalyptus, the challenges and some realistic prospects for the application of MAS to improve relevant traits are outlined. With the expected availability of more powerful genomic tools, including a draft of the Eucalyptus genome, the main challenges in implementing MAS will be in phenotyping trees accurately, analysing the overwhelming amount of genomic data available and translating this into truly useful molecular tools for breeding. (author)

  1. The floral transcriptome of Eucalyptus grandis

    CSIR Research Space (South Africa)

    Vining, KJ

    2015-10-01

    Full Text Available As a step toward functional annotation of genes required for floral initiation and development within the Eucalyptus genome, we used short read sequencing to analyze transcriptomes of floral buds from early and late developmental stages...

  2. Mechanical and thermal properties of electron beam-irradiated polypropylene reinforced with Kraft lignin

    Science.gov (United States)

    Sugano-Segura, A. T. R.; Tavares, L. B.; Rizzi, J. G. F.; Rosa, D. S.; Salvadori, M. C.; dos Santos, D. J.

    2017-10-01

    Polypropylene reinforced with Kraft lignin composites (0, 2.5, 5.0 and 10.0 wt% lignin) were submitted to electron beam (EB) irradiation at doses of 0, 50, 100 and 250 kGy. Kraft lignin incorporation maintained Young´s modulus values, even at electron beam doses up to 100 kGy (10 wt% lignin). The yield stress losses were also reduced by the addition of lignin to polypropylene. Fourier transform infrared spectroscopy (FTIR) results showed low formation of carboxyl and hydroxyl groups for composites containing lignin. Dynamic mechanical analysis (DMA) curves indicated a synergistic effect between Kraft lignin and electron beam irradiation on the storage modulus (E´). Several properties evolved as a function of the Kraft lignin content. Synergistic effects between Kraft lignin incorporation and electron beam radiation contribute to applications that require the mechanical and thermal properties of iPP to be maintained, even after high doses of electron beam radiation.

  3. Sublethal Effects of Chlorine-Free Kraft Mill Effluents on Daphnia magna.

    Science.gov (United States)

    Chamorro, Soledad; López, Daniela; Brito, Pablina; Jarpa, Mayra; Piña, Benjamin; Vidal, Gladys

    2016-12-01

    The implementation of elemental chlorine-free (ECF) bleaching methods has drastically reduced the aquatic toxicity of Kraft mill effluents during the last decade. However, the residual toxicity of Kraft mill effluents is still a potential concern for the environment, even when subjected to secondary wastewater treatment. The aim of this study is characterize potential sublethal effects of ECF Kraft mill effluents using Daphnia magna as model species. D. magna exposed towards increasing concentration of ECF Kraft mill effluent showed a significant, dose-dependent reduction in feeding. Conversely, post-feeding assay, life history, and allometric growth analyses showed stimulatory, rather than inhibitory effects in exposed animals at low concentrations, while high concentrations of ECF Kraft mill effluents reduced their reproductive output. These results suggest a hormetic effect in which moderate concentrations of the effluent had a stimulatory effect with higher concentrations causing inhibition in some variables.

  4. Comprehensive genetic dissection of wood properties in a widely-grown tropical tree: Eucalyptus

    Directory of Open Access Journals (Sweden)

    Ognouabi Nina

    2011-06-01

    Full Text Available Abstract Background Eucalyptus is an important genus in industrial plantations throughout the world and is grown for use as timber, pulp, paper and charcoal. Several breeding programmes have been launched worldwide to concomitantly improve growth performance and wood properties (WPs. In this study, an interspecific cross between Eucalyptus urophylla and E. grandis was used to identify major genomic regions (Quantitative Trait Loci, QTL controlling the variability of WPs. Results Linkage maps were generated for both parent species. A total of 117 QTLs were detected for a series of wood and end-use related traits, including chemical, technological, physical, mechanical and anatomical properties. The QTLs were mainly clustered into five linkage groups. In terms of distribution of QTL effects, our result agrees with the typical L-shape reported in most QTL studies, i.e. most WP QTLs had limited effects and only a few (13 had major effects (phenotypic variance explained > 15%. The co-locations of QTLs for different WPs as well as QTLs and candidate genes are discussed in terms of phenotypic correlations between traits, and of the function of the candidate genes. The major wood property QTL harbours a gene encoding a Cinnamoyl CoA reductase (CCR, a structural enzyme of the monolignol-specific biosynthesis pathway. Conclusions Given the number of traits analysed, this study provides a comprehensive understanding of the genetic architecture of wood properties in this Eucalyptus full-sib pedigree. At the dawn of Eucalyptus genome sequence, it will provide a framework to identify the nature of genes underlying these important quantitative traits.

  5. Comprehensive genetic dissection of wood properties in a widely-grown tropical tree: Eucalyptus.

    Science.gov (United States)

    Gion, Jean-Marc; Carouché, Audrey; Deweer, Sylvie; Bedon, Franck; Pichavant, Frédérique; Charpentier, Jean-Paul; Baillères, Henri; Rozenberg, Philippe; Carocha, Victor; Ognouabi, Nina; Verhaegen, Daniel; Grima-Pettenati, Jacqueline; Vigneron, Philippe; Plomion, Christophe

    2011-06-08

    Eucalyptus is an important genus in industrial plantations throughout the world and is grown for use as timber, pulp, paper and charcoal. Several breeding programmes have been launched worldwide to concomitantly improve growth performance and wood properties (WPs). In this study, an interspecific cross between Eucalyptus urophylla and E. grandis was used to identify major genomic regions (Quantitative Trait Loci, QTL) controlling the variability of WPs. Linkage maps were generated for both parent species. A total of 117 QTLs were detected for a series of wood and end-use related traits, including chemical, technological, physical, mechanical and anatomical properties. The QTLs were mainly clustered into five linkage groups. In terms of distribution of QTL effects, our result agrees with the typical L-shape reported in most QTL studies, i.e. most WP QTLs had limited effects and only a few (13) had major effects (phenotypic variance explained > 15%). The co-locations of QTLs for different WPs as well as QTLs and candidate genes are discussed in terms of phenotypic correlations between traits, and of the function of the candidate genes. The major wood property QTL harbours a gene encoding a Cinnamoyl CoA reductase (CCR), a structural enzyme of the monolignol-specific biosynthesis pathway. Given the number of traits analysed, this study provides a comprehensive understanding of the genetic architecture of wood properties in this Eucalyptus full-sib pedigree. At the dawn of Eucalyptus genome sequence, it will provide a framework to identify the nature of genes underlying these important quantitative traits.

  6. Bioethanol production from tension and opposite wood of Eucalyptus globulus using organosolv pretreatment and simultaneous saccharification and fermentation.

    Science.gov (United States)

    Muñoz, Claudio; Baeza, Jaime; Freer, Juanita; Mendonça, Regis Teixeira

    2011-11-01

    During tree growth, hardwoods can initiate the formation of tension wood, which is a strongly stressed wood on the upper side of the stem and branches. In Eucalyptus globulus, tension wood presents wider and thicker cell walls with low lignin, similar glucan and high xylan content, as compared to opposite wood. In this work, tension and opposite wood of E. globulus trees were separated and evaluated for the production of bioethanol using ethanol/water delignification as pretreatment followed by simultaneous saccharification and fermentation (SSF). Low residual lignin and high glucan retention was obtained in organosolv pulps of tension wood as compared to pulps from opposite wood at the same H-factor of reaction. The faster delignification was associated with the low lignin content in tension wood, which was 15% lower than in opposite wood. Organosolv pulps obtained at low and high H-factor (3,900 and 12,500, respectively) were saccharified by cellulases resulting in glucan-to-glucose yields up to 69 and 77%, respectively. SSF of the pulps resulted in bioethanol yields up to 35 g/l that corresponded to 85-95% of the maximum theoretical yield on wood basis, considering 51% the yield of glucose to ethanol conversion in fermentation, which could be considered a very satisfactory result compared to previous studies on the conversion of organosolv pulps from hardwoods to bioethanol. Both tension and opposite wood of E. globulus were suitable raw materials for organosolv pretreatment and bioethanol production with high conversion yields.

  7. Kraft Foods, Inc. in India — The Cadbury Acquisition

    OpenAIRE

    V. S. Pai; Ram Subramanian

    2014-01-01

    When the United States-based Kraft Foods, Inc. (KFI) acquired the United Kingdom-based Cadbury plc, KFI got entry into the Indian market. KFI CEO, Irene Rosenfeld had targeted the developing markets as key for the company to achieve a 5% organic growth rate and the strong position of Cadbury India augured well for expanding KFI's presence in that market. However, after nearly a year since the acquisition, KFI was moving slowly in India and appeared content to consolidate Cadbury's market pres...

  8. Effect of Aqueous Extracts of Eucalyptus Globulus, Citrus Sinensis ...

    African Journals Online (AJOL)

    Eucalyptus), Citrus sinensis (Sweet orange) and Musa sapientium (Banana) on the cowpea bruchid, Callosobruchus maculatus was investigated in the laboratory. There were four treatments namely aqueous extracts of Eucalyptus, Orange, Banana, ...

  9. Influência dos atributos do solo sobre a qualidade da madeira de Pinus taeda para produção de celulose Kraft Influence of soil attributes on quality of Pinus taeda wood for cellulose Kraft production

    Directory of Open Access Journals (Sweden)

    Patrícia Aparecida Rigatto

    2004-04-01

    characteristics, as well as their relation to cellulose production. Eight sites with twelve-year-old trees were selected based on soil type, soil texture and primary vegetation. The soil variables studied were bulk density, total porosity, macroporosity, water availability, fertility and grain size distribution. For tree selection, dendrometric measurements of 50 trees were taken per site, and 5 average size trees selected per site. Total and commercial height and DBH were measured and discs removed. Tree samples were analyzed for basic density, chemical composition, tracheid morphological characteristics, nutritional status and Kraft cellulose production. The soil chemical attributes exerted significant influence on wood quality, but the soil physical attributes showed greater influence on cellulose productivity. Sites with higher growth rate and those with clay texture showed lower values of basic density, higher content of extract and lignin, thus showing lower content of holocellulose and cellulose, shorter and wider tracheids with thinner walls and higher lumen diameters, and lower cellulose yield. Based on these results, it was concluded that cellulose pulp characteristics can be estimated by analyzing wood characteristics combined with the existing site edaphic conditions.

  10. EUCALYPTUS CELLULOSE MICRO/NANOFIBRILS IN EXTRUDED FIBERCEMENT COMPOSITES

    Directory of Open Access Journals (Sweden)

    Camila Soares Fonseca

    2016-03-01

    Full Text Available Extrusion is an alternative process for fiber-cement production and allows many advantages such as different geometries for the extruded products and the low initial investment for industrial production. In this context the aim of this study was to produce cellulose micro/nanofibrils from Eucalyptus pulp and evaluate the properties of cementitious composites made with different contents of cellulose micro/nanofibrils. Cellulose micro/ nanofibrils were produced using a mechanical defibrillator, and characterized for their morphology. Extruded composites were produced with 0.5 to 1.0% (by mass of micro/ nanofibrils and compared to unreinforced composites. Composites reinforced with 1.0% of micro/nanofibrils presented higher water absorption and apparent porosity than their counter parts. No significant differences were observed for modulus of rupture (MOR, limit of proportionality (LOP and final specific deformation, between the composites reinforced with 0.5% and 1.0% of micro/nanofibrils and those with no reinforcement. The static elastic modulus (MOE increased and specific energy decreased with the inclusion of 1.0% of micro/nanofibrils. Dynamic elastic modulus (E of the composites increased with the increase of micro/nanofibrils content and of weathering exposition. This study indicates that fiber-cements are sensitive to changes in structural composition and time of ageing (135 days. This information can be useful for developing of new products based on cellulose micro/nanofibrils.

  11. Biomechanical pulping of kenaf

    Science.gov (United States)

    Aziz Ahmed; Masood Akhtar; Gary C. Myers; Gary M. Scott

    1999-01-01

    The objective of this study was to investigate the effect of fungal pretreatment of whole kenaf prior to refining on refiner electrical energy consumption, paper strength, and optical properties. We also explored the suitability of whole kenaf biomechanical pulp for making newsprint in terms of ISO brightness and strength properties. Kenaf was sterilized by autoclaving...

  12. Infection and Pulp Regeneration

    Directory of Open Access Journals (Sweden)

    Sahng G. Kim

    2016-03-01

    Full Text Available The regeneration of the pulp-dentin complex has been a great challenge to both scientists and clinicians. Previous work has shown that the presence of prior infection may influence the characteristics of tissues formed in the root canal space after regenerative endodontic treatment. The formation of ectopic tissues such as periodontal ligament, bone, and cementum has been observed in the root canal space of immature necrotic teeth with apical periodontitis, while the regeneration of dentin and pulp has been identified in previously non-infected teeth. The current regenerative endodontic therapy utilizes disinfection protocols, which heavily rely on chemical irrigation using conventional disinfectants. From a microbiological point of view, the current protocols may not allow a sufficiently clean root canal microenvironment, which is critical for dentin and pulp regeneration. In this article, the significance of root canal disinfection in regenerating the pulp-dentin complex, the limitations of the current regenerative endodontic disinfection protocols, and advanced disinfection techniques designed to reduce the microorganisms and biofilms in chronic infection are discussed.

  13. The use of biomass energy in the pulp and paper industry and the prospects for black liquor gasification combined cycle generation

    International Nuclear Information System (INIS)

    Nilsson, L.J.

    1995-01-01

    The world production of paper and paperboard products, which increased 3.3% per year since 1980, reached 243 million tonnes in 1991 and is expected to continue to grow by about 2.5% per year over the next decade. Consumption levels in 1990 ranged from 2.8 kg per capita in India to 313 kg per capita in the United States. The biggest producers of pulp are the United States, Canada and the Scandinavian countries, but much of the expansion of pulp production capacity is taking place in countries such as Brazil, Chile and Indonesia. The pulp and paper industry has always relied on biomass as a fuel source to meet process energy demands. Kraft pulping is the most common process accounting for about two thirds of world wood pulp production. Energy recovered from burning black liquor, a lignin-rich by-product, in a chemicals recovery boiler typically provides most of the on-site demand for heat and electricity in a modem kraft pulp mill. Another important fuel source is bark and wood waste generated at the mill. Aging recovery boilers in industrialized countries and increasing electricity/heat demand ratios are stimulating interest in alternative co-generation technologies. Most of the interest in new biomass and black liquor co-generation technologies focuses on those that would utilize gas turbines rather than steam turbines. Gas turbines are generally characterized by higher electricity/heat ratios than steam turbines, as well as lower unit capital costs. With the black liquor and biomass gasification technologies that are now being developed and demonstrated, the energy needs of an energy-efficient kraft pulp mill could be met and 40-50 MW of baseload power would be available for export. Using, in addition, currently unused logging residues for fuel would increase that potential. The pulp and paper industry is likely to be an important early market for advanced biomass-based cogeneration technology owing to its access to biomass fuels and the potential for co

  14. Physical and mechanical properties of saligna eucalyptus grown in Hawaii

    Science.gov (United States)

    C.C. Gerhards

    1965-01-01

    Physical and mechanical properties were determined for saligna eucalyptus (Eucalyptus saligna, Smith) grown in Hawaii. In comparison with wood of the same species grown in Australia, saligna eucalyptus grown in Hawaii was lower in density, shrinkage, and compressive strength parallel to grain; it was about equal in strength in bending and shear; and it was stiffer....

  15. Effects of Allelochemicals of Some Eucalyptus Species on ...

    African Journals Online (AJOL)

    A laboratory experiment was conducted to assess the effects of allelochemicals of Eucalyptus camaldulensis, Eucalyptus citriodora and Eucalyptus globules on germination and root elongation using leguminous crop ground nut (Arachis hypogea) as bioassay material. The experiments were conducted in sterilized ...

  16. Eucalyptus microsatellites mined in silico: survey and evaluation

    Indian Academy of Sciences (India)

    2008-04-01

    Apr 1, 2008 ... Eucalyptus leucoxylon (Myrtaceae) and their utility for Ecolog- ical and breeding studies in other Eucalyptus Species. J. Hered. 96, 445–451. Poke F. S., Vaillancourt R. E., Potts B. M. and Reid J. B. 2005 Ge- nomic research in Eucalyptus. Genetica 125, 79–101. Qureshi S. N., Saha S., Varshney R. V. and ...

  17. Aggregate stability in soils cultivated with eucalyptus

    Directory of Open Access Journals (Sweden)

    Junior Cesar Avanzi

    2011-01-01

    Full Text Available The objective of this work was to evaluate the aggregate stability of tropical soils under eucalyptus plantation and native vegetation, and assess the relationships between aggregate stability and some soil chemical and physical properties. Argisols, Cambisol, Latosols and Plinthosol within three eucalyptus-cultivated regions, in the states of Espírito Santo, Rio Grande do Sul and Minas Gerais, Brazil, were studied. For each region, soils under native vegetation were compared to those under minimum tillage with eucalyptus cultivation. The aggregate stability was measured using the high-energy moisture characteristic (HEMC technique, i.e., the moisture release curve at very low suctions. This method compares the resistance of aggregates to slaking on a relative scale from zero to one. Thus, the aggregate stability from different soils and management practices can be directly compared. The aggregate stability ratio was greater than 50% for all soils, which shows that the aggregate stability index is high, both in eucalyptus and native vegetation areas. This suggests that soil management adopted for eucalyptus cultivation does not substantially modify this property. In these soils, the aggregate stability ratio does not show a good relationship with clay or soil organic matter contents. However, soil organic matter shows a positive relationship with clay content and cation exchange capacity.

  18. Eucalyptus growth promotion by endophytic Bacillus spp.

    Science.gov (United States)

    Paz, I C P; Santin, R C M; Guimarães, A M; Rosa, O P P; Dias, A C F; Quecine, M C; Azevedo, J L; Matsumura, A T S

    2012-10-11

    Clonal eucalyptus plantings have increased in recent years; however, some clones with high production characteristics have vegetative propagation problems because of weak root and aerial development. Endophytic microorganisms live inside healthy plants without causing any damage to their hosts and can be beneficial, acting as plant growth promoters. We isolated endophytic bacteria from eucalyptus plants and evaluated their potential in plant growth promotion of clonal plantlets of Eucalyptus urophylla x E. grandis, known as the hybrid, E. urograndis. Eighteen isolates of E. urograndis, clone 4622, were tested for plant growth promotion using the same clone. These isolates were also evaluated for indole acetic acid production and their potential for nitrogen fixation and phosphate solubilization. The isolates were identified by partial sequencing of 16S rRNA. Bacillus subtilis was the most prevalent species. Several Bacillus species, including B. licheniformis and B. subtilis, were found for the first time as endophytes of eucalyptus. Bacillus sp strain EUCB 10 significantly increased the growth of the root and aerial parts of eucalyptus plantlets under greenhouse conditions, during the summer and winter seasons.

  19. Evaluation of Pulp and Paper Properties obtained from Maple Juvenile Wood through Organosolv Alcohol Method Catalyzed by Calcium and Magnesium Salts

    Directory of Open Access Journals (Sweden)

    Reza Naghdi

    2015-05-01

    Full Text Available The properties of catalyzed organosolv pulp obtained from maple juvenile wood were studied. The physical properties of fiber (e.g. length, width, and cell membrane thickness and chemical composition of maple juvenile wood (e.g. average cellulose, lignin, extractives, and ash content were determined. The variables were cooking temperature (190 and 200 ºC and time (40, 60, and 80 minutes. Chemical charge ( 280 ml methanol, 70 ml water, and 0.025 mols of Calcium Chloride and Magnesium Nitrate was kept constant. Pulp screen yields (54.9 to 60.91% and Kappa No. (15.5 to 18.4 were measured. Pulp freeness was reduced to 350 ml CSF in PFI mill, and ten 60 g/m2 handsheets were made from the selected pulps. The strength properties of catalyzed organosolv handsheets including tear length (3.83 to 4.25 km, tear index (10.22 to 12.81 mN.m2/g, and burst index (1.74 to 2.15 kPa.m2/g were compared with those of the conventional Kraft handsheets of maple juvenile wood. The least allowed values of the mentioned properties in the Indian (IS and Japanese international standards (JIS reveal that while the tear length value is slightly below that of the standards, the values of tear and burst indices are well beyond the given standards, and the environmentally-friendly catalyzed organosolv pulping process (higher yield and lower Kappa No. compared to Kraft can be recommended to produce paper pulp from maple juvenile wood.

  20. The genome of Eucalyptus grandis

    Energy Technology Data Exchange (ETDEWEB)

    Myburg, Alexander A.; Grattapaglia, Dario; Tuskan, Gerald A.; Hellsten, Uffe; Hayes, Richard D.; Grimwood, Jane; Jenkins, Jerry; Lindquist, Erika; Tice, Hope; Bauer, Diane; Goodstein, David M.; Dubchak, Inna; Poliakov, Alexandre; Mizrachi, Eshchar; Kullan, Anand R. K.; Hussey, Steven G.; Pinard, Desre; van der Merwe, Karen; Singh, Pooja; van Jaarsveld, Ida; Silva-Junior, Orzenil B.; Togawa, Roberto C.; Pappas, Marilia R.; Faria, Danielle A.; Sansaloni, Carolina P.; Petroli, Cesar D.; Yang, Xiaohan; Ranjan, Priya; Tschaplinski, Timothy J.; Ye, Chu-Yu; Li, Ting; Sterck, Lieven; Vanneste, Kevin; Murat, Florent; Soler, Marçal; Clemente, Hélène San; Saidi, Naijib; Cassan-Wang, Hua; Dunand, Christophe; Hefer, Charles A.; Bornberg-Bauer, Erich; Kersting, Anna R.; Vining, Kelly; Amarasinghe, Vindhya; Ranik, Martin; Naithani, Sushma; Elser, Justin; Boyd, Alexander E.; Liston, Aaron; Spatafora, Joseph W.; Dharmwardhana, Palitha; Raja, Rajani; Sullivan, Christopher; Romanel, Elisson; Alves-Ferreira, Marcio; Külheim, Carsten; Foley, William; Carocha, Victor; Paiva, Jorge; Kudrna, David; Brommonschenkel, Sergio H.; Pasquali, Giancarlo; Byrne, Margaret; Rigault, Philippe; Tibbits, Josquin; Spokevicius, Antanas; Jones, Rebecca C.; Steane, Dorothy A.; Vaillancourt, René E.; Potts, Brad M.; Joubert, Fourie; Barry, Kerrie; Pappas, Georgios J.; Strauss, Steven H.; Jaiswal, Pankaj; Grima-Pettenati, Jacqueline; Salse, Jérôme; Van de Peer, Yves; Rokhsar, Daniel S.; Schmutz, Jeremy

    2014-06-11

    Eucalypts are the world s most widely planted hardwood trees. Their broad adaptability, rich species diversity, fast growth and superior multipurpose wood, have made them a global renewable resource of fiber and energy that mitigates human pressures on natural forests. We sequenced and assembled >94% of the 640 Mbp genome of Eucalyptus grandis into its 11 chromosomes. A set of 36,376 protein coding genes were predicted revealing that 34% occur in tandem duplications, the largest proportion found thus far in any plant genome. Eucalypts also show the highest diversity of genes for plant specialized metabolism that act as chemical defence against biotic agents and provide unique pharmaceutical oils. Resequencing of a set of inbred tree genomes revealed regions of strongly conserved heterozygosity, likely hotspots of inbreeding depression. The resequenced genome of the sister species E. globulus underscored the high inter-specific genome colinearity despite substantial genome size variation in the genus. The genome of E. grandis is the first reference for the early diverging Rosid order Myrtales and is placed here basal to the Eurosids. This resource expands knowledge on the unique biology of large woody perennials and provides a powerful tool to accelerate comparative biology, breeding and biotechnology.

  1. Increased delignification rate of Dendrocalamus strictus (Roxburgh nees by Schizophyllum commune Fr.; Fr. to reduce chemical consumption during pulping process

    Directory of Open Access Journals (Sweden)

    Vipin Kumar Saini

    2013-08-01

    Full Text Available Pulp and paper industry is traditionally known to be a large contributor to environmental pollution due its largeconsumption of energy and chemicals. To reduce the chemical consumption, rate of delignification was increased bySchizophyllum commune in destructured sample of Dendrocalamus stictus, which was destructured by Impressafiner (compression-cum dewatering process. The extent of delignification was determined and comparison was made between thenon-destructured and destructured samples. The influence of physical parameters like incubation time, moisture level, media,media concentration, pH and temperature were also examined during the study. It was found that rate of delignification wassignificantly 6.43% more in destructured sample than non-destructured sample. Kraft pulping of treated destructured sampleshows 2.59 point reduction in kappa number than untreated non-destructured sample. Thus this paper provides an insight ofthe delignification extent in Dendrocalamus strictus after mechanical operation at varying physical parameters.

  2. Botanical, Phytochemical, and Anticancer Properties of the Eucalyptus Species.

    Science.gov (United States)

    Vuong, Quan V; Chalmers, Anita C; Jyoti Bhuyan, Deep; Bowyer, Michael C; Scarlett, Christopher J

    2015-06-01

    The genus Eucalyptus (Myrtaceae) is mainly native to Australia; however, some species are now distributed globally. Eucalyptus has been used in indigenous Australian medicines for the treatment of a range of aliments including colds, flu, fever, muscular aches, sores, internal pains, and inflammation. Eucalyptus oils containing volatile compounds have been widely used in the pharmaceutical and cosmetics industries for a multitude of purposes. In addition, Eucalyptus extracts containing nonvolatile compounds are also an important source of key bioactive compounds, and several studies have linked Eucalyptus extracts with anticancer properties. With the increasing research interest in Eucalyptus and its health properties, this review briefly outlines the botanical features of Eucalyptus, discusses its traditional use as medicine, and comprehensively reviews its phytochemical and anticancer properties and, finally, proposes trends for future studies. Copyright © 2015 Verlag Helvetica Chimica Acta AG, Zürich.

  3. TANNIN CONTENT DETERMINATION IN THE BARK OF Eucalyptus spp

    Directory of Open Access Journals (Sweden)

    Paulo Fernando Trugilho

    2003-07-01

    Full Text Available The objective of this study was to determine the tannin contents in the bark oftwenty-five species of Eucalyptus through two extraction methods, one using hot water andthe other a sequence of toluene and ethanol. The results showed that the extraction methodspresented significant differences in the tannin contents. The method using the sequencetoluene and ethanol, for most of the species, promoted a larger extraction of tannin. The hotwater method presented higher contents of tannin for Eucalyptus cloeziana (40,31%,Eucalyptus melanophoia (20,49% and Eucalyptus paniculata (16,03%. In the toluene andethanol method the species with higher tannin content was Eucalyptus cloeziana (31,00%,Eucalyptus tereticornis (22,83% and Eucalyptus paniculata (17,64%. The Eucalyptuscloeziana presented great potential as commercial source of tannin, independent of theextraction method considered.

  4. Vahur Kraft kraamis eile oma sahtlid Eesti Pangas tühjaks / Urmas Tooming

    Index Scriptorium Estoniae

    Tooming, Urmas

    2005-01-01

    6. juunil oli Vahur Krafti viimane tööpäev Eesti Panga presidendina. Lisad: CV; Keskpanga ekspresident Vahur Kraft juhtis 10 aastat Eesti pangandust. Kommenteerivad Eesti Panga endine asepresident Heldur Meerits ja endine Hansapanga juht Indrek Neivelt

  5. Jens Kraft og "De vilde Folk" (1760) - manden, forfatterskbet, værket

    DEFF Research Database (Denmark)

    Langkjær, Michael Alexander

    2000-01-01

    that all cultures have passed through similar stages of development? C. What contemporary intellectual and institutional circumstances in Denmark and what personal motives might have induced Kraft to write a secular history of human development? In attempting to answere these and other questions, I put......Jens Kraft and his Brief Account of the Principal Institutions, Customs and Ideas of the Savage Peoples, to Inform about the General Origins and Development of Humanity, Sorø, 1760 - The man, his writings, his book. The present dissertation presents some results of my research on Jens Kraft...... Norse peoples, thus offering an explanation of the general development of human culture: how it originates, and, more importantly, why, in some cases it did not progress beyond a certain level. Kraft shows that man's natural mode of development is a slow, uncertain process, quickened only...

  6. Precipitation and characterisation of lignin obtained from South African kraft mill black liquor

    CSIR Research Space (South Africa)

    Namane, M

    2014-07-01

    Full Text Available International Conference on Chemical Thermodynamics and South African Institution of Chemical Engineering Conference, Durban, South Africa, 27 July - 1 August 2014 Precipitation and characterisation of lignin obtained from South African kraft mill black...

  7. Effects of Treatment Materials on the Physical Properties of Eucalyptus (Eucalyptus camaldulensis Dehn. Wood

    Directory of Open Access Journals (Sweden)

    Selahattin Bardak

    2011-04-01

    Full Text Available This study was designed to determine effects on retention and shrink levels of Eucalyptus (Eucalyptus camaldulensis Dehn. which treated with some commercial preservative types, borates, polyethylene glycol, and water repellents. In this study, four type impregnation chemicals were chosen: 1. Commercial preservative types, [Ammonium sulphate, Vacsol-WR WR and Immersol-WR (WR], 2. Borates chemicals, [Boric acid, Borax, Boric acid+ Borax] 3. Polyethylene glycol such as Polyethylene glycol (PEG-400 4. Water repellents [Styrene, Methylmetacrylate.]. As a result, retention % and shrink levels of Eucalyptus wood was lower treated with commercial preservative types and borates preservatives compare to other treatment chemicals. However, retention % levels of Eucalyptus wood treated with WR chemicals were highly significant levels. According to their leachability period although PEG 400 showed antishrink effectiveness other treatments didnt showed antishrink efficiency.

  8. Development of a strategy for energy efficiency improvement in a Kraft process based on systems interactions analysis

    Science.gov (United States)

    Mateos-Espejel, Enrique

    The objective of this thesis is to develop, validate, and apply a unified methodology for the energy efficiency improvement of a Kraft process that addresses globally the interactions of the various process systems that affect its energy performance. An implementation strategy is the final result. An operating Kraft pulping mill situated in Eastern Canada with a production of 700 adt/d of high-grade bleached pulp was the case study. The Pulp and Paper industry is Canada's premier industry. It is characterized by large thermal energy and water consumption. Rising energy costs and more stringent environmental regulations have led the industry to refocus its efforts toward identifying ways to improve energy and water conservation. Energy and water aspects are usually analyzed independently, but in reality they are strongly interconnected. Therefore, there is a need for an integrated methodology, which considers energy and water aspects, as well as the optimal utilization and production of the utilities. The methodology consists of four successive stages. The first stage is the base case definition. The development of a focused, reliable and representative model of an operating process is a prerequisite to the optimization and fine tuning of its energy performance. A four-pronged procedure has been developed: data gathering, master diagram, utilities systems analysis, and simulation. The computer simulation has been focused on the energy and water systems. The second stage corresponds to the benchmarking analysis. The benchmarking of the base case has the objectives of identifying the process inefficiencies and to establish guidelines for the development of effective enhancement measures. The studied process is evaluated by a comparison of its efficiency to the current practice of the industry and by the application of new energy and exergy content indicators. The minimum energy and water requirements of the process are also determined in this step. The third stage is

  9. THE EFFECT OF HEAT TREATMENT ON SOME PROPERTIES AND COLOUR IN EUCALYPTUS (Eucalyptus camaldulensis DEHN.) WOOD

    OpenAIRE

    Unsal,O; Korkut,S; Atik,C

    2003-01-01

    Heat treatment is often applied to some wood species to improve dimensional stability. This study evaluated the effect of heat treatment on some physical and mechanical properties and colour of Eucalyptus wood (Eucalyptus camaldulensis Dehn.), which has industrially high usage potential and large plantations in Turkey. Wood specimens from Tarsus, Turkey were subjected to heat treatment in varying temperatures and durations. After the heat treatment, hardness, swelling, ovendry density, and co...

  10. Actinomycetes from Eucalyptus and their biological activities for controlling Eucalyptus leaf and shoot blight.

    Science.gov (United States)

    Himaman, Winanda; Thamchaipenet, Arinthip; Pathom-Aree, Wasu; Duangmal, Kannika

    2016-01-01

    In Thailand, Eucalyptus plantations rapidly expand across the country. Leaf and shoot blight caused by Cryptosporiopsis eucalypti, Cylindrocladium sp. and Teratosphaeria destructans is a serious disease in Eucalyptus plantations. In this study, a total of 477 actinomycete strains were successfully isolated from roots and rhizosphere soil of Eucalyptus. Four hundred and thirty nine isolates were classified as streptomycetes and 38 isolates were non-streptomycetes. Among these isolates, 272 (57.0%), 118 (24.7%) and 241 (50.5%) isolates were antagonistic to Cryptosporiopsis eucalypti, Cylindrocladium sp. and Teratosphaeria destructans, respectively. All isolates were tested for their abilities to produce siderophores, indole acetic acid (IAA) and solubilise phosphate. Most isolates (464, 97.3%) produced siderophores. The majority of isolates (345, 72.3%) solubilised phosphate. In addition, almost half of these isolates (237, 49.7%) produced indole acetic acid. Strain EUSKR2S82 which showed the strongest inhibitory effect against all tested fungi with plant growth promoting ability was selected to test with Eucalyptus. This strain could colonize plant roots and increase Eucalyptus roots length. In a detached leaves bioassay, the disease severity of EUSKR2S82-inoculated Eucalyptus leaves was only 30% compared to 95% in the control treatment. The 16S rRNA gene sequence analysis revealed that the strain EUSKR2S82 was related to Streptomyces ramulosus NRRL-B 2714(T) (99.44% similarity). Identification of non-streptomycete isolates using 16S rRNA gene sequences classified them into 9 genera: Actinoallomurus, Actinomadura, Amycolatopsis, Cryptosporangium, Microbispora, Micromonospora, Nocardia, Nonomuraea and Pseudonocardia. It is evident that Eucalyptus tree harbored several genera of actinomycetes. The selected isolate, EUSKR2S82 showed potential as a candidate for biocontrol agent of leaf and shoot blight of Eucalyptus and to promote growth. Copyright © 2016 Elsevier Gmb

  11. Caracterização de compostos reduzidos de enxofre gerados na produção de celulose kraft e pré-hidrólise kraft.

    Directory of Open Access Journals (Sweden)

    Afonso Moraes de Moura

    2010-08-01

    Full Text Available Um problema ambiental da indústria de celulose kraft é o odor causado pela emissão dos compostos reduzidos de enxofre gerados pela deslignificação de madeiras de um modo em geral. Para monitorar essas emissões, existem equipamentos simples, desenvolvidos para a medição contínua do "total reduced sulphur" (TRS, tal como o analisador coulométrico. Neste trabalho, foram analisados sulfeto de hidrogênio (H2S, metil mercaptana (CH3SH, dimetil sulfeto [(CH32S] e dimetil dissulfeto [(CH32S2], gerados em deslignificações laboratoriais kraft e pré-hidrólise kraft de dois grupos de madeiras de folhosas. Um dos grupos de madeiras continha 25% e o outro 20% de lignina, base peso seco. Foi observado que as madeiras com menores teores de lignina geraram significativamente menores quantidades de compostos reduzidos de enxofre de TRS. Não foram notadas diferenças significativas nas quantidades totais geradas entre os processos de deslignificação estudados. O processo pré-hidrólise kraft foi mais sensível aos teores de lignina da madeira que o processo kraft. Recomenda-se, por isso, trabalhar com madeiras com menores teores de lignina quando do uso do processo pré-hidrólise kraft para produção de celulose. As principais formas geradas de TRS foram dimetil sulfeto e metil mercaptana.

  12. Mycosphaerella and Teratosphaeria species associated with leaf diseases on Eucalyptus globulus in southern Brazil

    Directory of Open Access Journals (Sweden)

    Marcela G. TEODORO

    2012-09-01

    Full Text Available Leaf blight and defoliation caused by Teratosphaeria species is one of the most important leaf diseases of Eucalyptus globulus. Due to the importance of this tree species for the production of pulp and paper, and recent reports of severe leaf disease symptoms in Brazil, the present study was conducted to identify the pathogen(s involved. Symptomatic leaves were collected in the Brazilian states of Paraná and Rio Grande do Sul, single ascospore cultures established, and isolates were investigated using DNA-based molecular tools. A species-specific PCR and sequence data from the nuclear ribosomal DNA operon were used for species identification. The following seven species were identified: Mycosphaerella scytalidii, Dissoconium dekkeri (=M. lateralis, Teratosphaeria ohnowa, T. perpendicularis, T. pseudafricana, T. flexuosa and T.nubilosa. Of the recorded species, T. nubilosa is regarded as the most serious threat to the cultivation of E. globulus in the states surveyed.

  13. Innovations in papermaking: an LCA of printing and writing paper from conventional and high yield pulp.

    Science.gov (United States)

    Manda, B M Krishna; Blok, Kornelis; Patel, Martin K

    2012-11-15

    Pulp and paper industry is facing challenges such as resource scarcity and greenhouse gas (GHG) emissions. The objective of this research is to investigate whether the use of new coatings (micro or nano TiO(2)) and different pulp types could bring savings in wood, energy, GHG emissions and other environmental impacts in comparison with conventional printing and writing paper. We studied three types of pulp, namely i) unbleached virgin kraft pulp, ii) recovered fiber, and iii) high yield virgin chemithermo-mechanical pulp (CTMP). A life cycle assessment (LCA) was conducted from cradle to grave. Applying attributional modeling, we found that wood savings amount to 60% for the nanoparticle coated recovered fiber paper and 35% for the micro TiO(2) coated CTMP paper. According to the ReCiPe single score impact assessment method, the new product configurations allow the reduction of the environmental impacts by 10-35% compared to conventional kraft paper. Applying consequential modeling, we found larger energy and GHG emission savings compared to attributional modeling because the saved wood is used for producing energy, thereby replacing fossil fuels. The nanoparticle coated recovered fiber paper offered savings of non-renewable energy use (NREU) by 100% (13GJ/ton paper) and GHG emission reduction by 75% (0.6 tonCO(2)eq./ton paper). Micro TiO(2) coated CTMP paper offered NREU savings by 25% (3GJ/ton paper) and savings of GHG emissions by 10% (0.1 tonCO(2)eq./ton paper). The taking into account of all environmental impacts with the ReCiPe single score method leads to comparable results as that of attributional modeling. We conclude that the nanoparticle coated recovered fiber paper offered the highest savings and lowest environmental impacts. However, human toxicity and ecotoxicity impacts of the nanoparticles were not included in this analysis and need further research. If this leads to the conclusion that the toxicity impacts of the nanoparticles are serious, then the

  14. Innovations in papermaking: An LCA of printing and writing paper from conventional and high yield pulp

    International Nuclear Information System (INIS)

    Manda, B.M. Krishna; Blok, Kornelis; Patel, Martin K.

    2012-01-01

    Pulp and paper industry is facing challenges such as resource scarcity and greenhouse gas (GHG) emissions. The objective of this research is to investigate whether the use of new coatings (micro or nano TiO 2 ) and different pulp types could bring savings in wood, energy, GHG emissions and other environmental impacts in comparison with conventional printing and writing paper. We studied three types of pulp, namely i) unbleached virgin kraft pulp, ii) recovered fiber, and iii) high yield virgin chemithermo-mechanical pulp (CTMP). A life cycle assessment (LCA) was conducted from cradle to grave. Applying attributional modeling, we found that wood savings amount to 60% for the nanoparticle coated recovered fiber paper and 35% for the micro TiO 2 coated CTMP paper. According to the ReCiPe single score impact assessment method, the new product configurations allow the reduction of the environmental impacts by 10–35% compared to conventional kraft paper. Applying consequential modeling, we found larger energy and GHG emission savings compared to attributional modeling because the saved wood is used for producing energy, thereby replacing fossil fuels. The nanoparticle coated recovered fiber paper offered savings of non-renewable energy use (NREU) by 100% (13 GJ/ton paper) and GHG emission reduction by 75% (0.6 ton CO 2 eq./ton paper). Micro TiO 2 coated CTMP paper offered NREU savings by 25% (3 GJ/ton paper) and savings of GHG emissions by 10% (0.1 ton CO 2 eq./ton paper). The taking into account of all environmental impacts with the ReCiPe single score method leads to comparable results as that of attributional modeling. We conclude that the nanoparticle coated recovered fiber paper offered the highest savings and lowest environmental impacts. However, human toxicity and ecotoxicity impacts of the nanoparticles were not included in this analysis and need further research. If this leads to the conclusion that the toxicity impacts of the nanoparticles are serious, then

  15. Atmospheric emission of nitrogen oxide from kraft recovery boilers in Sweden

    International Nuclear Information System (INIS)

    Kjoerk, Anders; Herstad Swaerd, Solvie

    2000-05-01

    Recovery boiler NO x emissions are low compared with those from power boilers. However tighter environmental requirements to decrease the acidic emissions implies that all sources have to be addressed. There are an ongoing evaluation and development of NO x control technologies in the pulp industry. Basically air staging, selective catalytic reduction, SCR, and selective noncatalytic reduction, SNCR, have been discussed. Other NO x control options may be available as a result of ongoing research and development. As a background in the work to reduce the acid rain it has been considered necessary to have a good picture of the NO x emission from recovery boilers, and the Thermal Engineering Research Institute in Sweden have therefore sponsored this study. The intention is to give a good general view and try to explain the reasons for the large differences between boilers. Data from the 30 kraft recovery boilers which were in operation in Sweden during 1999 have been collected. Both NO x levels and specific conditions which could have an influence on the level have been included. The evaluation show a clear correlation between the nitrogen content in the liquor and the NO x level. It seams also that a long retention time in the furnace give an opportunity to reduce the amount of nitrogen oxide. For most boilers in Sweden the NO x levels are reported in mg/MJ and comparison could be done between different types of boilers. However for recovery boilers there could be a large uncertainty in the calculation which gives the amount (mg) of NO x , the definition of the heat input to be used (MJ) is either not clear. As a base for the study the measured concentration in ppm is used instead. The reported values are in the range of 30 - 100 ppm, however the majority of the boilers operate in a more narrow range 60-80 ppm. Air staging and other combustion methods could not reasonably reduce the NO x emission with more than 20% in the next decade. If the goal is higher other

  16. Effect of Soda-Anthraquinone Pulping Conditions and Beating Revolution on the Mechanical Properties of Paper made from Gigantochloa scortechinii (Semantan Bamboo)

    International Nuclear Information System (INIS)

    Nurul Husna Mohd Hassan; Suhaimi Muhammed

    2013-01-01

    The effect of soda-AQ pulping conditions and beating revolution on the mechanical properties of paper made from Semantan bamboo (Gigantochloa scortechinii) was studied. The bamboo chips were pulped using MK digester pulping unit with 10 to 20 % alkali charge and 150 to 170 degree Celsius cooking temperature. The screened yield varies from 38.7 to 48.4 %, and each yield went through beating process at 1000 or 8000 beating revolutions. The bamboo pulp was then made into 60 g/ m 2 laboratory scale papers and their mechanical properties were assessed conforming to TAPPI standards. The results revealed that tensile index, bursting index, tearing index and folding endurance ranged from 42.04 to 91.09 Nm/ g, 2.68 to 7.10 kPa.m 2 /g, 11.03 to 26.64 mN.m 2 /g and 30 to 1127 double folds, respectively. The highest paper properties were found from pulping condition of 15 % alkali charge and 150 degree Celsius cooking temperature based on the fibre bonding index, with tensile index at 87.71 Nm/g, bursting index at 6.94 kPa.m 2 / g, tearing index at 12.72 mN.m 2 / g and folding endurance at 613 double folds. Such findings indicate that comparable high strength mechanical properties of paper can be produced from Semantan bamboo pulp with more environmentally friendly pulping process compared to the kraft pulping process that had been used in bamboo pulping. (author)

  17. Allelopathic Effects of Eucalyptus Tereticornis on Phaseolus ...

    African Journals Online (AJOL)

    The water extracts of leaves (green, brown and decayed stages) and bark of Eucalyptus tereticornis were tested for seed germination and primary root and shoot development of Phaseolus vulgaris seedlings. There was no significant difference in the germination percentage of Phaseolus vulgaris due to the treatments of ...

  18. Growth and yield in Eucalyptus globulus

    Science.gov (United States)

    James A. Rinehart; Richard B. Standiford

    1983-01-01

    A study of the major Eucalyptus globulus stands throughout California conducted by Woodbridge Metcalf in 1924 provides a complete and accurate data set for generating variable site-density yield models. Two models were developed using linear regression techniques. Model I depicts a linear relationship between age and yield best used for stands between five and fifteen...

  19. Managing a Coastal Bluegum (Eucalyptus globules) forest

    Science.gov (United States)

    Ralph S. Osterling

    1983-01-01

    Eucalyptus was thought to be a replacement to oak and other hardwoods for many products. Thousands of acres have been planted and now are in need of management. Management techniques are discussed in context with a coastal stand of approximately 300 acres of mixed aged bluegum. Potential markets are explored.

  20. Allelopathic effects of invasive Eucalyptus camaldulensis on ...

    African Journals Online (AJOL)

    Eucalyptus camaldulensis Dehnh. (red river gum; Myrtaceae) is an invasive tree in riparian habitats of the Western Cape, South Africa, where it replaces indigenous vegetation and affects ecosystem functioning. These invasions lead to changes in river geomorphology and reduction in stream flow. The mechanisms that ...

  1. Eucalyptus-wheat interaction on Ethiopian Nitosols

    NARCIS (Netherlands)

    Kidanu, S.; Mamo, T.; Stroosnijder, L.

    2004-01-01

    Over the past few years a single row of Eucalyptus globulus trees planted along the borders of cropland has come to dominate central highland agroforestry practices. Although evidence is scanty, there is a perception that this practice adversely affects crop productivity. An on-farm trial was

  2. Determination of pectin content of eucalyptus wood

    NARCIS (Netherlands)

    Coetzee, B.; Schols, H.A.; Wolfaardt, F.

    2011-01-01

    Very little is known about the occurrence of pectin in wood and it is speculated that between 10 mg g-1 and 40 mg g-1 of wood consists of pectin. The present study aimed to quantify pectin in eucalyptus wood and to determine the influence of tree species, yield potential of the site, tree age class

  3. Selective enrichment of a methanol-utilizing consortium using pulp & paper mill waste streams

    Energy Technology Data Exchange (ETDEWEB)

    Gregory R. Mockos; William A. Smith; Frank J. Loge; David N. Thompson

    2007-04-01

    Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater . Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Waste activated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25°C with a hydraulic residence time and a solids retention time of four days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24 hour feed/decant cycles ranged from 79 to 89 %, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen limited conditions. This indicates that selectively-enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents.

  4. Selective enrichment of a methanol-utilizing consortium using pulp and paper mill waste streams.

    Science.gov (United States)

    Mockos, Gregory R; Smith, William A; Loge, Frank J; Thompson, David N

    2008-03-01

    Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater. Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Waste-activated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25 degrees C with a hydraulic residence time and a solids retention time of 4 days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24-h feed/decant cycles ranged from 79 to 89%, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste-activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen-limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen-limited conditions. This indicates that selectively enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents.

  5. Selective Enrichment of a Methanol-Utilizing Consortium Using Pulp and Paper Mill Waste Streams

    Science.gov (United States)

    Mockos, Gregory R.; Smith, William A.; Loge, Frank J.; Thompson, David N.

    Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater. Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Wasteactivated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25°C with a hydraulic residence time and a solids retention time of 4 days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24-h feed/ decant cycles ranged from 79 to 89%, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste-activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen-limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen-limited conditions. This indicates that selectively enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents.

  6. Flexible biorefinery for producing fermentation sugars, lignin and pulp from corn stover.

    Science.gov (United States)

    Kadam, Kiran L; Chin, Chim Y; Brown, Lawrence W

    2008-05-01

    A new biorefining process is presented that embodies green processing and sustainable development. In the spirit of a true biorefinery, the objective is to convert agricultural residues and other biomass feedstocks into value-added products such as fuel ethanol, dissolving pulp, and lignin for resin production. The continuous biomass fractionation process yields a liquid stream rich in hemicellulosic sugars, a lignin-rich liquid stream, and a solid cellulose stream. This paper generally discusses potential applications of the three streams and specifically provides results on the evaluation of the cellulose stream from corn stover as a source of fermentation sugars and specialty pulp. Enzymatic hydrolysis of this relatively pure cellulose stream requires significantly lower enzyme loadings because of minimal enzyme deactivation from nonspecific binding to lignin. A correlation was shown to exist between lignin removal efficiency and enzymatic digestibility. The cellulose produced was also demonstrated to be a suitable replacement for hardwood pulp, especially in the top ply of a linerboard. Also, the relatively pure nature of the cellulose renders it suitable as raw material for making dissolving pulp. This pulping approach has significantly smaller environmental footprint compared to the industry-standard kraft process because no sulfur- or chlorine-containing compounds are used. Although this option needs some minimal post-processing, it produces a higher value commodity than ethanol and, unlike ethanol, does not need extensive processing such as hydrolysis or fermentation. Potential use of low-molecular weight lignin as a raw material for wood adhesive production is discussed as well as its use as cement and feed binder. As a baseline application the hemicellulosic sugars captured in the hydrolyzate liquor can be used to produce ethanol, but potential utilization of xylose for xylitol fermentation is also feasible. Markets and values of these applications are

  7. Bioenergy for District Bioheating System (DBS) from eucalyptus residues in a European coal-producing region

    International Nuclear Information System (INIS)

    Paredes-Sánchez, José P.; López-Ochoa, Luis M.; López-González, Luis M.; Xiberta-Bernat, Jorge

    2016-01-01

    Highlights: • The paper introduces a combined method to evaluate bioenergy. • Forest biomass needs to be studied as a fuel supplier and carbon sink. • The forests under study produce about 28 kt dry and 0.15 Mt CO 2 per year. • Examined a District Bioheating System (DBS) with the available biomass. - Abstract: Since forest biomass can substitute for CO 2 -emitting fossil fuels in the energy sector, forest management can greatly affect the global carbon cycle. Eucalyptus globulus has adapted very well in the coal region of the Principality of Asturias (Northwestern Spain) and has become highly regarded as a valuable raw material for the pulp and paper industry. In the present work, the Eucalyptus globulus is studied as a key natural energy source in order to improve existing methods and develop new ways of optimizing the evaluation and use of both forest biomass and woody residue in energy systems, in accordance with sustainable forestry industry safety and environmental requirements. The feasibility of utilizing forest biomass instead of natural gas in a District Bioheating System (DBS) has been examined based on an analysis of its economical and environmental impacts.

  8. New species, hyper-diversity and potential importance of Calonectria spp. from Eucalyptus in South China.

    Science.gov (United States)

    Lombard, L; Chen, S F; Mou, X; Zhou, X D; Crous, P W; Wingfield, M J

    2015-03-01

    Plantation forestry is expanding rapidly in China to meet an increasing demand for wood and pulp products globally. Fungal pathogens including species of Calonectria represent a serious threat to the growth and sustainability of this industry. Surveys were conducted in the Guangdong, Guangxi and Hainan Provinces of South China, where Eucalyptus trees in plantations or cuttings in nurseries displayed symptoms of leaf blight. Isolations from symptomatic leaves and soils collected close to infected trees resulted in a large collection of Calonectria isolates. These isolates were identified using the Consolidated Species Concept, employing morphological characters and DNA sequence comparisons for the β-tubulin, calmodulin, histone H3 and translation elongation factor 1-alpha gene regions. Twenty-one Calonectria species were identified of which 18 represented novel taxa. Of these, 12 novel taxa belonged to Sphaero-Naviculate Group and the remaining six to the Prolate Group. Southeast Asia appears to represent a centre of biodiversity for the Sphaero-Naviculate Group and this fact could be one of the important constraints to Eucalyptus forestry in China. The remarkable diversity of Calonectria species in a relatively small area of China and associated with a single tree species is surprising.

  9. Kinetics of pulp mill effluent treatment by ozone-based processes

    International Nuclear Information System (INIS)

    Ko, Chun-Han; Hsieh, Po-Hung; Chang, Meng-Wen; Chern, Jia-Ming; Chiang, Shih-Min; Tzeng, Chewn-Jeng

    2009-01-01

    The wastewaters generated from wood pulping and paper production processes are traditionally treated by biological and physicochemical processes. In order to reduce chemical oxygen demand (COD) and color to meet increasingly strict discharge standards, advanced oxidation processes (AOPs) are being adapted as polishing treatment units. Various ozone-based processes were used in this study to treat simulated wastewaters prepared from black liquor from a hardwood Kraft pulp mill in Taiwan. The experimental results showed that the COD and color were primarily removed by direct ozone oxidation and activated carbon adsorption. While the addition of activated carbon could enhance the COD and color removal during ozonation, the addition of hydrogen peroxide improved the color removal only. For the various ozone-based treatment processes, kinetic models were developed to satisfactorily predict the COD and color removal rates. According to the kinetic parameters obtained from the various ozone-based processes, the enhanced COD and color removal of ozonation in the presence of activated carbon was attributed to the regeneration of the activated carbon by ozonation. These kinetic models can be used for reactor design and process design to treat pulping wastewater using ozone-based processes.

  10. Kinetics of pulp mill effluent treatment by ozone-based processes.

    Science.gov (United States)

    Ko, Chun-Han; Hsieh, Po-Hung; Chang, Meng-Wen; Chern, Jia-Ming; Chiang, Shih-Min; Tzeng, Chewn-Jeng

    2009-09-15

    The wastewaters generated from wood pulping and paper production processes are traditionally treated by biological and physicochemical processes. In order to reduce chemical oxygen demand (COD) and color to meet increasingly strict discharge standards, advanced oxidation processes (AOPs) are being adapted as polishing treatment units. Various ozone-based processes were used in this study to treat simulated wastewaters prepared from black liquor from a hardwood Kraft pulp mill in Taiwan. The experimental results showed that the COD and color were primarily removed by direct ozone oxidation and activated carbon adsorption. While the addition of activated carbon could enhance the COD and color removal during ozonation, the addition of hydrogen peroxide improved the color removal only. For the various ozone-based treatment processes, kinetic models were developed to satisfactorily predict the COD and color removal rates. According to the kinetic parameters obtained from the various ozone-based processes, the enhanced COD and color removal of ozonation in the presence of activated carbon was attributed to the regeneration of the activated carbon by ozonation. These kinetic models can be used for reactor design and process design to treat pulping wastewater using ozone-based processes.

  11. Use of an expert system for energy cost calculations in the pulp and paper industry

    International Nuclear Information System (INIS)

    Viinikainen, S.; Malinen, H.

    1991-12-01

    In this paper, an application for the calculation of energy prices and product energy costs in the pulp and paper industry by using the Xi Plus expert system is presented. The use of expert systems in the energy field and also the Xi Plus expert system and its general features are also discussed. The application has been made after collecting data from several sources. It runs in an IBM AT compatible microcomputer therefore being easily used in mills. The name of the application is PRODUCT ENERGY COST. It has a three level structure: the mill level, the department level and the main equipment level. Currently, the mill level and, in the energy production area, the department level (power plant) and the equipment level (boilers, turbines) are used. The application consists of four knowledge base groups. Altogether there are 52 separate knowledge bases having 534 rules or demons. The knowledge base groups are: BASIC DATA, ENERGY USE, ENERGY PRODUCTION and ENERGY COSTS. The application can be used for various heat and electrical energy price calculations or for energy cost calculations for different pulp and paper products. In this study, the energy prices for kraft pulp, TMP, newsprint and fine paper in different operating conditions and the associated energy costs of the products are calculated. Also, in some cases a sensitivity analysis is done. The expert system is quite suitable for this type of calculation and the method could be further developed for specific industrial needs, e.g. to enhance the energy management systems

  12. Generation of Hydrogen, Lignin and Sodium Hydroxide from Pulping Black Liquor by Electrolysis

    Directory of Open Access Journals (Sweden)

    Guangzai Nong

    2015-12-01

    Full Text Available Black liquor is generated in Kraft pulping of wood or non-wood raw material in pulp mills, and regarded as a renewable resource. The objective of this paper was to develop an effective means to remove the water pollutants by recovery of both lignin and sodium hydroxide from black liquor, based on electrolysis. The treatment of a 1000 mL of black liquor (122 g/L solid contents consumed 345.6 kJ of electric energy, and led to the generation of 30.7 g of sodium hydroxide, 0.82 g of hydrogen gas and 52.1 g of biomass solids. Therefore, the recovery ratios of elemental sodium and biomass solids are 80.4% and 76%, respectively. Treating black liquor by electrolysis is an environmentally friendly technology that can, in particular, be an alternative process in addressing the environmental issues of pulping waste liquor to the small-scale mills without black liquor recovery.

  13. Strong and Optically Transparent Films Prepared Using Cellulosic Solid Residue Recovered from Cellulose Nanocrystals Production Waste Stream

    Science.gov (United States)

    Qianqian Wang; J.Y. Zhu; John M. Considine

    2013-01-01

    We used a new cellulosic material, cellulosic solid residue (CSR), to produce cellulose nanofibrils (CNF) for potential high value applications. Cellulose nanofibrils (CNF) were produced from CSR recovered from the hydrolysates (waste stream) of acid hydrolysis of a bleached Eucalyptus kraft pulp (BEP) to produce nanocrystals (CNC). Acid hydrolysis greatly facilitated...

  14. Production and improved bleaching abilities of a thermostable ...

    African Journals Online (AJOL)

    Administrator

    2011-10-19

    Oct 19, 2011 ... 121, 137 and 334 U/ml, when using birch wood xylan, beech wood xylan and corncobs xylan respectively, as substrates. .... carried out under optimized nutritional and fermentation conditions for maximum yield of the ..... 11-3 and its application in biobleaching of eucalyptus kraft pulp. Enzyme Microb.

  15. determination of lipophilic extractives in ionic liquid extracts

    African Journals Online (AJOL)

    dell

    Chem. 9: 63-69. Freire CSR, Pinto PCR, Santiago AS,. Silvestre AJD, Evtuquin DV and Neto. CP 2006a Comparative study of lipophilic extractives of hardwoods and corresponding ECF bleached kraft pulps. BioResources. 1: 3-17. Freire CSR, Silvestre AJD and Neto CP. 2005. Lipophilic extractives in. Eucalyptus globulus.

  16. Effects of wet-pressing-induced fiber hornification on enzymatic saccharification of lignocelluloses

    Science.gov (United States)

    X.L. Luo; Junyong Zhu; Roland Gleisner; H.Y. Zhan

    2011-01-01

    This article reports the effect of wet-pressing-induced fiber hornification on enzymatic saccharification of lignocelluloses. A wet cellulosic substrate of bleached kraft eucalyptus pulp and two wet sulfite-pretreated lignocellulosic substrates of aspen and lodgepole pine were pressed to various moisture (solids) contents by variation of pressing pressure and pressing...

  17. Integrated production of nano-fibrillated cellulose and cellulosic biofuel (ethanol) by enzymatic fractionation of wood fibers

    Science.gov (United States)

    Junyong Zhu; Ronald Sabo; Xiaolin Luo

    2011-01-01

    This study demonstrates the feasibility of integrating the production of nano-fibrillated cellulose (NFC), a potentially highly valuable biomaterial, with sugar/biofuel (ethanol) from wood fibers. Commercial cellulase enzymes were used to fractionate the less recalcitrant amorphous cellulose from a bleached Kraft eucalyptus pulp, resulting in a highly crystalline and...

  18. Optimizing cellulose fibrillation for the production of cellulose nanofibrils by a disk grinder

    Science.gov (United States)

    Chuanshuang Hu; Yu Zhao; Kecheng Li; J.Y. Zhu; Roland Gleisner

    2015-01-01

    The fibrillation of a bleached kraft eucalyptus pulp was investigated by means of a laboratory-scale disk grinder for the production of cellulose nanofibrils (CNF), while the parameters disk rotating speed, solid loading, and fibrillation duration were varied. The cumulative energy consumption was monitored during fibrillation. The degree of polymerization (DP) and...

  19. Is Pulp Inflammation a Prerequisite for Pulp Healing and Regeneration?

    Science.gov (United States)

    Goldberg, Michel; Njeh, Akram; Uzunoglu, Emel

    2015-01-01

    The importance of inflammation has been underestimated in pulpal healing, and in the past, it has been considered only as an undesirable effect. Associated with moderate inflammation, necrosis includes pyroptosis, apoptosis, and nemosis. There are now evidences that inflammation is a prerequisite for pulp healing, with series of events ahead of regeneration. Immunocompetent cells are recruited in the apical part. They slide along the root and migrate toward the crown. Due to the high alkalinity of the capping agent, pulp cells display mild inflammation, proliferate, and increase in number and size and initiate mineralization. Pulp fibroblasts become odontoblast-like cells producing type I collagen, alkaline phosphatase, and SPARC/osteonectin. Molecules of the SIBLING family, matrix metalloproteinases, and vascular and nerve mediators are also implicated in the formation of a reparative dentinal bridge, osteo/orthodentin closing the pulp exposure. Beneath a calciotraumatic line, a thin layer identified as reactionary dentin underlines the periphery of the pulp chamber. Inflammatory and/or noninflammatory processes contribute to produce a reparative dentinal bridge closing the pulp exposure, with minute canaliculi and large tunnel defects. Depending on the form and severity of the inflammatory and noninflammatory processes, and according to the capping agent, pulp reactions are induced specifically. PMID:26538825

  20. Predicting the most appropriate wood biomass for selected industrial applications: comparison of wood, pulping, and enzymatic treatments using fluorescent-tagged carbohydrate-binding modules.

    Science.gov (United States)

    Bombeck, Pierre-Louis; Khatri, Vinay; Meddeb-Mouelhi, Fatma; Montplaisir, Daniel; Richel, Aurore; Beauregard, Marc

    2017-01-01

    Lignocellulosic biomass will progressively become the main source of carbon for a number of products as the Earth's oil reservoirs disappear. Technology for conversion of wood fiber into bioproducts (wood biorefining) continues to flourish, and access to reliable methods for monitoring modification of such fibers is becoming an important issue. Recently, we developed a simple, rapid approach for detecting four different types of polymer on the surface of wood fibers. Named fluorescent-tagged carbohydrate-binding module (FTCM), this method is based on the fluorescence signal from carbohydrate-binding modules-based probes designed to recognize specific polymers such as crystalline cellulose, amorphous cellulose, xylan, and mannan. Here we used FTCM to characterize pulps made from softwood and hardwood that were prepared using Kraft or chemical-thermo-mechanical pulping. Comparison of chemical analysis (NREL protocol) and FTCM revealed that FTCM results were consistent with chemical analysis of the hemicellulose composition of both hardwood and softwood samples. Kraft pulping increased the difference between softwood and hardwood surface mannans, and increased xylan exposure. This suggests that Kraft pulping leads to exposure of xylan after removal of both lignin and mannan. Impact of enzyme cocktails from Trichoderma reesei (Celluclast 1.5L) and from Aspergillus sp. (Carezyme 1000L) was investigated by analysis of hydrolyzed sugars and by FTCM. Both enzymes preparations released cellobiose and glucose from pulps, with the cocktail from Trichoderma being the most efficient. Enzymatic treatments were not as effective at converting chemical-thermomechanical pulps to simple sugars, regardless of wood type. FTCM revealed that amorphous cellulose was the primary target of either enzyme preparation, which resulted in a higher proportion of crystalline cellulose on the surface after enzymatic treatment. FTCM confirmed that enzymes from Aspergillus had little impact on

  1. Preparation of clinker from paper pulp industry wastes.

    Science.gov (United States)

    Buruberri, Leire H; Seabra, M P; Labrincha, J A

    2015-04-09

    The production of paper pulp by the Kraft method generates considerable amounts of wastes. Namely, lime mud generated in the recovery circuit of chemical reagents, biological sludge from the wastewater treatment of wood digestion process and fly ash collected in the fluidized bed combustor used to generate electricity from biomass burning. The final destination of such wastes is an important concern, since environmental regulations are becoming stricter regarding their landfill. Driven by this fact, industries are looking for more sustainable solutions, such as the recycling in distinct products. This work tested these wastes as secondary raw materials to produce clinker/cement that was then experienced in mortar formulations. The first step involved the residues detailed characterization and a generated amounts survey. Then, specific but simple steps were suggested, aiming to facilitate transport and manipulation. Distinct blends were prepared and fired in order to get belitic and Portland clinkers. The Portland clinkers were processed at lower temperatures than the normally used in the industry due to the presence of mineralizing impurities in some wastes. Belite-based cements were used to produce mortars that developed satisfactory mechanical strength and did not reveal signs of deterioration or durability weaknesses. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Decellularized Swine Dental Pulp as a Bioscaffold for Pulp Regeneration

    OpenAIRE

    Hu, Lei; Gao, Zhenhua; Xu, Junji; Zhu, Zhao; Fan, Zhipeng; Zhang, Chunmei; Wang, Jinsong; Wang, Songlin

    2017-01-01

    Endodontic regeneration shows promise in treating dental pulp diseases; however, no suitable scaffolds exist for pulp regeneration. Acellular natural extracellular matrix (ECM) is a favorable scaffold for tissue regeneration since the anatomical structure and ECM of the natural tissues or organs are well-preserved. Xenogeneic ECM is superior to autologous or allogeneic ECM in tissue engineering for its unlimited resources. This study investigated the characteristics of decellularized dental p...

  3. Is Eucalyptus Cryptically Self-incompatible?

    Science.gov (United States)

    Horsley, Tasmien N; Johnson, Steven D

    2007-12-01

    The probability that seeds will be fertilized from self- versus cross-pollen depends strongly on whether plants have self-incompatibility systems, and how these systems influence the fate of pollen tubes. In this study of breeding systems in Eucalyptus urophylla and Eucalyptus grandis, epifluorescence microscopy was used to study pollen tube growth in styles following self- and cross-pollinations. Pollen tubes from self-pollen took significantly longer than those from cross-pollen to grow to the base of the style in both E. urophylla (120 h vs. 96 h) and E. grandis (96 h vs. 72 h). In addition, both species exhibited reduced seed yields following self-pollination compared with cross-pollination. The present observations suggest that, in addition to a late-acting self-incompatibility barrier, cryptic self-incompatibility could be a mechanism responsible for the preferential out-crossing system in these two eucalypt species.

  4. Experimental Studies on the Hydrotreatment of Kraft Lignin to Aromatics and Alkylphenolics Using Economically Viable Fe-Based Catalysts

    NARCIS (Netherlands)

    Agarwal, Shilpa; Chowdari, Ramesh Kumar; Hita, Idoia; Heeres, Hero Jan

    Limonite, a low-cost iron ore, was investigated as a potential hydrotreatment catalyst for kraft lignin without the use of an external solvent (batch reactor, initial H-2 pressure of 100 bar, 4 h). The best results were obtained at 450 degrees C resulting in 34 wt % of liquefied kraft lignin (lignin

  5. Pulp and paper industry

    Energy Technology Data Exchange (ETDEWEB)

    Viinikainen, S.; Nousiainen, I.; Edelman, K.; Manninen, J.

    2002-07-01

    The pulp and paper industry has played a major role in Finland with regards to energy use, technological development and the economy. Finland's market share in printing and writing paper exports is 25%. Finnish companies now figure among the world's biggest pulp and paper enterprises through international consolidations. Finnish equipment manufacturers, control system suppliers and consulting engineering firms are also global players. Rapid technological changes have taken place in the unit sizes of main process equipment or whole production lines. Environmental effects have been reduced significantly, e.g. biological oxygen demand load has been reduced from 530 000 to 18 000 t/a in the last 30 years, even though the production of paper and board has tripled. Competitiveness in the future depends on the supply of raw material, energy use, environmental issues as well as on the development of information and communication technology (ICT) for transferring and storing information. The growth rate of paper products has been closely interconnected with economic development. The average annual increase in the production volume has been 2-3%, whereas the real price of products has followed a declining trend. The first indication of the effects of ICT is seen in the reduced newsprint demand in the US market. It is foreseen that the use of cut-size office papers will increase, together with individual printing. Global growth in the demand for paper products is expected to slow down but not to cease because of this development. Forest growth in Finland currently exceeds annual harvesting. Taking into account the changes in forest ownership, taxation principles and forest land protection, an increase in harvesting of 5-10% is feasible. The amount of imported wood is expected to increase also in the future. Utilisation of the available fibre supply has to be further optimised in terms of endproduct properties. Since the investment in a new production line is already

  6. Exploitation des fleurs de Entada africana, Eucalyptus ...

    African Journals Online (AJOL)

    A Dang, de décembre 2001 à mai 2002, puis de décembre 2002 à mai 2003, les fleurs de Entada africana, Eucalyptus camaldulensis, Psidium guajava et Trichillia emetica ont été observées en vue de l'étude de l'activité de l'abeille Apis mellifera adansonii. L'objectif principal de cette recherche était la détermination de la ...

  7. Evaluation of lignins from side-streams generated in an olive tree pruning-based biorefinery: Bioethanol production and alkaline pulping.

    Science.gov (United States)

    Santos, José I; Fillat, Úrsula; Martín-Sampedro, Raquel; Eugenio, María E; Negro, María J; Ballesteros, Ignacio; Rodríguez, Alejandro; Ibarra, David

    2017-12-01

    In modern lignocellulosic-based biorefineries, carbohydrates can be transformed into biofuels and pulp and paper, whereas lignin is burned to obtain energy. However, a part of lignin could be converted into value-added products including bio-based aromatic chemicals, as well as building blocks for materials. Then, a good knowledge of lignin is necessary to define its valorisation procedure. This study characterized different lignins from side-streams produced from olive tree pruning bioethanol production (lignins collected from steam explosion pretreatment with water or phosphoric acid as catalysts, followed by simultaneous saccharification and fermentation process) and alkaline pulping (lignins recovered from kraft and soda-AQ black liquors). Together with the chemical composition, the structure of lignins was investigated by FTIR, 13 C NMR, and 2D NMR. Bioethanol lignins had clearly distinct characteristics compared to pulping lignins; a certain number of side-chain linkages (mostly alkyl-aryl ether and resinol) accompanied with lower phenolic hydroxyls content. Bioethanol lignins also showed a significant amount of carbohydrates, mainly glucose and protein impurities. By contrast, pulping lignins revealed xylose together with a dramatical reduction of side-chains (some resinol linkages survive) and thereby higher phenol content, indicating rather severe lignin degradation during alkaline pulping processes. All lignins showed a predominance of syringyl units. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Comparison of two continuous fungal bioreactors for posttreatment of anaerobically pretreated weak black liquor from kraft pulp mills.

    Science.gov (United States)

    Ortega-Clemente, Alfredo; Marín-Mezo, G; Ponce-Noyola, M T; Montes-Horcasitas, M C; Caffarel-Méndez, S; Barrera-Cortés, Josefina; Poggi-Varaldo, Héctor M

    2007-03-01

    The purpose of this work was to evaluate and compare two continuous systems of posttreatment of anaerobically pretreated weak black liquor (WBL). The first system consisted of a packed bed reactor (PBR) with Trametes versicolor (Tv) immobilized on wood cubes of holm oak (biocubes). The second system was a fluidized bed reactor (FBR) with Lentinus edodes (Le) immobilized on wood cubes of holm oak. The reactors operated for 65 days at a hydraulic retention time (HRT) of 5 days, at 28 degrees C, with continuous aeration. Response variables monitored were conventional and specific, unit, net removal efficiency (eta and eta(sun), respectively) of chemical oxygen demand (COD), color, and ligninoids, and enzymatic activities of manganese peroxidase (MnP), lignin peroxidase (LiP), laccase (Lac) and proteases. The PBR showed an average color eta superior to that of the FBR (52.42 +/- 21.78% and 25.34 +/- 14.38% for PBR and FBR, respectively); removals of COD and ligninoids presented a similar pattern to that of color. Lac activity was significantly larger in PBR than in FBR. Activity of MnP in PBR was higher than that of the FBR (0.004 and 0.002 U MnP/mL, respectively). This difference could be ascribed to the different fungi present in each bioreactor. LiP activity was very low in both reactors. Average value of proteases was almost double in the FBR as compared with PBR (0.472 and 0.209 U Proteases/mL, respectively). During the last 2 weeks of operation, biocubes in the FBR experienced a significant loss of the attached Le biomass, probably by attrition. This and higher protease activity in the FBR could explain the lower pollutant removals achieved in the FBR. Overall, PBR with immobilized Tv showed a better performance than the FBR with Le for the posttreatment of the recalcitrant anaerobic effluent. Extended and sustained pollutant removal (65 days) was achieved in the PBR, although more research is needed to evaluate bioreactor performance at shorter hydraulic retention times.

  9. Assessing the application of advanced oxidation processes, and their combination with biological treatment, to effluents from pulp and paper industry.

    Science.gov (United States)

    Merayo, Noemí; Hermosilla, Daphne; Blanco, Laura; Cortijo, Luis; Blanco, Angeles

    2013-11-15

    The closure of water circuits within pulp and paper mills has resulted in a higher contamination load of the final mill effluent, which must consequently be further treated in many cases to meet the standards imposed by the legislation in force. Different treatment strategies based on advanced oxidation processes (ozonation and TiO2-photocatalysis), and their combination with biological treatment (MBR), are herein assessed for effluents of a recycled paper mill and a kraft pulp mill. Ozone treatment achieved the highest efficiency of all. The consumption of 2.4 g O3 L(-1) resulted in about a 60% COD reduction treating the effluent from the kraft pulp mill at an initial pH=7; although it only reached about a 35% COD removal for the effluent of the recycled paper mill. Otherwise, photocatalysis achieved about a 20-30% reduction of the COD for both type of effluents. In addition, the effluent from the recycled paper mill showed a higher biodegradability, so combinations of these AOPs with biological treatment were tested. As a result, photocatalysis did not report any significant COD reduction improvement whether being performed as pre- or post-treatment of the biological process; whereas the use of ozonation as post-biological treatment enhanced COD removal a further 10%, summing up a total 90% reduction of the COD for the combined treatment, as well as it also supposed an increase of the presence of volatile fatty acids, which might ultimately enable the resultant wastewater to be recirculated back to further biological treatment. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Methanol production from eucalyptus wood chips. Attachment V. The Florida eucalyptus energy farm: environmental impacts

    Energy Technology Data Exchange (ETDEWEB)

    Fishkind, H.H.

    1982-06-01

    The overall environmental impact of the eucalyptus to methanol energy system in Florida is assessed. The environmental impacts associated with the following steps of the process are considered: (1) the greenhouse and laboratory; (2) the eucalyptus plantation; (3) transporting the mature logs; (4) the hammermill; and (5) the methanol synthesis plant. Next, the environmental effects of methanol as an undiluted motor fuel, methanol as a gasoline blend, and gasoline as motor fuels are compared. Finally, the environmental effects of the eucalypt gasification/methanol synthesis system are compared to the coal liquefaction and conversion system.

  11. Jens Kraft og "De vilde Folk" (1760) - manden, forfatterskbet, værket

    DEFF Research Database (Denmark)

    Langkjær, Michael Alexander

    2000-01-01

    to call it a programmatic statement of Kraft's mindset and preoccupations as a mathematician. In addition, I believe that he was a heterodox Christian who wished to show that a man could acquire a true knowledge of God only with the help of Revelation. To him mathematical truth and divine truth were two...... be viewed as an expression of that fact and as an aplogetics of the theology of Revelation and Providence directed against the assumptions of a deistic natural religion and naturalistic materialism. 5. Kraft's interest in acquiring an understanding of man's natural cognitive processes derived from a wish...

  12. Effect of Eucalyptus camaldulensis stand Conversion into Crop ...

    African Journals Online (AJOL)

    Bheema

    croplands afforested with Eucalyptus camaldulensis can be reused for annual crop production after its removal. In this study, we ... In Ethiopia about 5-10 species of Eucalyptus are widely planted for various uses (Friis, 1995). In the highlands of Ethiopia, ... There is no sufficient scientific evidence regarding reclamation of ...

  13. Energy, chemicals and carbon: future options for the Eucalyptus ...

    African Journals Online (AJOL)

    This paper examines the current Eucalyptus value chain and the possible drivers that may impact upon it. The potential consequences of climate change on the growth and yield of Eucalyptus are discussed and the impact of the security of oil reserves and increased costs of fossil-fuel-derived energy and raw materials upon ...

  14. Diseases on Eucalyptus species in Zimbabwean plantations and ...

    African Journals Online (AJOL)

    Zimbabwe embarked on planting Eucalyptus species in the early 1900s. Based on a robust breeding programme, it has become a major source of seed for other countries in and outside Africa. Tree health surveys conducted on Eucalyptus in some east and southern African countries over the past two decades have ...

  15. Clonal differences in log end splitting in Eucalyptus grandis in ...

    African Journals Online (AJOL)

    This paper discusses the juvenile–mature correlation of log end splitting among Eucalyptus grandis clones from two trials and how differences in splitting relate to differences in wood density, pith-to-bark gradient and growth rate. Two approximately 20-year-old Eucalyptus grandis clonal trials at Bergvliet plantation were ...

  16. Profitability of Eucalyptus growing in Busiro, Mpigi District, Uganda ...

    African Journals Online (AJOL)

    The worthiness of investments in eucalyptus growing has been determined using the net present value (NPV) criterion. It has been proved that investments in eucalyptus growing in perpetuity (forever) and being harvested on a four (4) year rotation period can earn a present value of a perpetual periodic annuity of Ug. shs ...

  17. USE OF EUCALYPTUS WOOD FOR ORIENTED STRAND BOARD (OSB MANUFACTURING

    Directory of Open Access Journals (Sweden)

    Setsuo Iwakiri

    2004-06-01

    Full Text Available This research evaluated the potential use of Eucalyptus species for OSB manufacturing. The boards were manufactured at the density of 0,70 g/cm³ and 6% of the phenol-formaldheyde resin contents. The following Eucalyptus species were studied: E. grandis E. dunnii ,E. tereticornis E. saligna ,E. citriodora, and E. maculata. The results of the physical and mechanical property tests showed high potentiality of the uses of Eucalyptus grandis and Eucalyptus saligna for OSB manufacturing, Boards manufactured with Eucalyptus grandis wood presented similar or higher average values for physical and mechanical properties, in comparison to Pinus taeda, which is the main species used for OSB production in Brazil.

  18. Variation in natural durability of seven Eucalyptus grandis x Eucalyptus urophylla hybrid clones

    Science.gov (United States)

    F.J.N. Franca; T.S.F.A. Franca; R.A Arango; B.M. Woodward; G.B. Vidaurre

    2017-01-01

    Programs aimed at developing clones of hybrid trees are commonly established in Brazil to meet the demands of various forest-based industries. These programs have continually improved the quality of eucalyptus wood, which has the potential to reduce deforestation by lowering demand for other high-value species. This is particularly true in the lumber market, but little...

  19. A comparison of cellulose nanofibrils produced from Cladophora glomerata algae and bleached eucalyptus pulp

    Science.gov (United States)

    Zhouyang Xiang; Wenhua Gao; Liheng Chen; Wu Lan; Junyong Zhu; Troy Runge

    2016-01-01

    Cladophora, a fresh-water green macroalgae, has unique cellulose properties and thus may be promising for production of cellulose nanofibrils (CNFs). Cellulose was extracted from Cladophora glomerata and subjected to microfluidization with or without enzymatic hydrolysis pretreatment to produce CNFs. Increasing...

  20. A microsatellite-based consensus linkage map for species of Eucalyptus and a novel set of 230 microsatellite markers for the genus

    Directory of Open Access Journals (Sweden)

    Williams Emlyn R

    2006-09-01

    Full Text Available Abstract Background Eucalypts are the most widely planted hardwood trees in the world occupying globally more than 18 million hectares as an important source of carbon neutral renewable energy and raw material for pulp, paper and solid wood. Quantitative Trait Loci (QTLs in Eucalyptus have been localized on pedigree-specific RAPD or AFLP maps seriously limiting the value of such QTL mapping efforts for molecular breeding. The availability of a genus-wide genetic map with transferable microsatellite markers has become a must for the effective advancement of genomic undertakings. This report describes the development of a novel set of 230 EMBRA microsatellites, the construction of the first comprehensive microsatellite-based consensus linkage map for Eucalyptus and the consolidation of existing linkage information for other microsatellites and candidate genes mapped in other species of the genus. Results The consensus map covers ~90% of the recombining genome of Eucalyptus, involves 234 mapped EMBRA loci on 11 linkage groups, an observed length of 1,568 cM and a mean distance between markers of 8.4 cM. A compilation of all microsatellite linkage information published in Eucalyptus allowed us to establish the homology among linkage groups between this consensus map and other maps published for E. globulus. Comparative mapping analyses also resulted in the linkage group assignment of other 41 microsatellites derived from other Eucalyptus species as well as candidate genes and QTLs for wood and flowering traits published in the literature. This report significantly increases the availability of microsatellite markers and mapping information for species of Eucalyptus and corroborates the high conservation of microsatellite flanking sequences and locus ordering between species of the genus. Conclusion This work represents an important step forward for Eucalyptus comparative genomics, opening stimulating perspectives for evolutionary studies and

  1. Biocomposite of Cassava Starch Reinforced with Cellulose Pulp Fibers Modified with Deposition of Silica (SiO2 Nanoparticles

    Directory of Open Access Journals (Sweden)

    Joabel Raabe

    2015-01-01

    Full Text Available Eucalyptus pulp cellulose fibers were modified by the sol-gel process for SiO2 superficial deposition and used as reinforcement of thermoplastic starch (TPS. Cassava starch, glycerol, and water were added at the proportion of 60/26/14, respectively. For composites, 5% and 10% (by weight of modified and unmodified pulp fibers were added before extrusion. The matrix and composites were submitted to thermal stability, tensile strength, moisture adsorption, and SEM analysis. Micrographs of the modified fibers revealed the presence of SiO2 nanoparticles on fiber surface. The addition of modified fibers improved tensile strength in 183% in relation to matrix, while moisture adsorption decreased 8.3%. Such improvements were even more effective with unmodified fibers addition. This result was mainly attributed to poor interaction between modified fibers and TPS matrix detected by SEM analysis.

  2. An Analytical System Designed to Measure Multiple Malodorous Compounds Related to Kraft Mill Activities.

    Science.gov (United States)

    Mulik, J. D.; And Others

    Reported upon in this research study is the development of two automated chromatographs equipped with flame photometric detectors for the qualitative and quantitative analysis of both low- and high-molecular weight sulfur compounds in kraft mill effluents. In addition the study sought to determine the relationship between total gaseous sulfur and…

  3. Combustion properties of kraft black liquors; Mustalipeaen koostumuksen vaikutus lipeaen poltto-ominaisuuksiin

    Energy Technology Data Exchange (ETDEWEB)

    Alen, R.; Siistonen, H.; Heikkinen, T.; Malkavaara, P. [Jyvaeskylae Univ. (Finland)

    1996-12-01

    The aim of this work is to study the combustion properties of kraft black liquors from modified cooking. Both the industrial and laboratory-made black liquors are included. In addition, changes in the combustion properties of the spent liquors obtained by mixing prior to combustion different chlorine-free bleach liquors with black liquor are studied. (author)

  4. Precipitation and valorisation of lignin in South African kraft mill black liquor - first stages: Poster

    CSIR Research Space (South Africa)

    Namane, M

    2013-10-01

    Full Text Available environmentally sustainable. The aims objectives of the current project is to precipitate and characterize lignin form kraft black liquor with an attempts to obtain narrow molecular weight lignin that can further be valorised to encourage Biorefineries in South...

  5. Chemical Modification of Kraft Lignin: Effect on Chemical and Thermal Properties

    Science.gov (United States)

    Yao Chen; Nicole M. Stark; Zhiyong Cai; Charles R. Frihart; Linda F. Lorenz; Rebecca E. Ibach

    2014-01-01

    Esterified kraft lignins (KL) were prepared by reaction with maleic anhydride (MA), succinic anhydride (SA), and phthalic anhydride (PA) in acetone solutions. The esterified lignins were characterized using ATR-FTIR, solid state CP-MAS 13C NMR spectroscopy, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). PA...

  6. Wood adhesives from Eucalyptus tar and creosote

    OpenAIRE

    Pimenta, AS; Vital, BR; Fujiwara, FY

    1997-01-01

    This study has shown that Eucalyptus tar and creosote can be used in phenolic adhesive formulations (resols) for wood products bonding. Some adhesives were prepared substituting 0; 17.7; 35.0 and 67.0% of the phenol by anhydrous tar and 0; 15.0 e 28.5% by creosote. In gluing Brazilian pine veneers, eucalypt tar and creosote based adhesives required longer pressing times for curing than conventional phenol-formaldehyde adhesives. By using C-13 NMR, the number of carbons in side chains and hydr...

  7. Biomechanical pulping : a mill-scale evaluation

    Science.gov (United States)

    Masood. Akhtar; Gary M. Scott; Ross E. Swaney; Mike J. Lentz; Eric G. Horn; Marguerite S. Sykes; Gary C. Myers

    1999-01-01

    Mechanical pulping process is electrical energy intensive and results in low paper strength. Biomechanical pulping, defined as the fungal treatment of lignocellulosic materials prior to mechanical pulping, has shown at least 30% savings in electrical energy consumption, and significant improvements in paper strength properties compared to the control at a laboratory...

  8. Oldest known Eucalyptus macrofossils are from South America.

    Directory of Open Access Journals (Sweden)

    María A Gandolfo

    Full Text Available The evolutionary history of Eucalyptus and the eucalypts, the larger clade of seven genera including Eucalyptus that today have a natural distribution almost exclusively in Australasia, is poorly documented from the fossil record. Little physical evidence exists bearing on the ancient geographical distributions or morphologies of plants within the clade. Herein, we introduce fossil material of Eucalyptus from the early Eocene (ca. 51.9 Ma Laguna del Hunco paleoflora of Chubut Province, Argentina; specimens include multiple leaves, infructescences, and dispersed capsules, several flower buds, and a single flower. Morphological similarities that relate the fossils to extant eucalypts include leaf shape, venation, and epidermal oil glands; infructescence structure; valvate capsulate fruits; and operculate flower buds. The presence of a staminophore scar on the fruits links them to Eucalyptus, and the presence of a transverse scar on the flower buds indicates a relationship to Eucalyptus subgenus Symphyomyrtus. Phylogenetic analyses of morphological data alone and combined with aligned sequence data from a prior study including 16 extant eucalypts, one outgroup, and a terminal representing the fossils indicate that the fossils are nested within Eucalyptus. These are the only illustrated Eucalyptus fossils that are definitively Eocene in age, and the only conclusively identified extant or fossil eucalypts naturally occurring outside of Australasia and adjacent Mindanao. Thus, these fossils indicate that the evolution of the eucalypt group is not constrained to a single region. Moreover, they strengthen the taxonomic connections between the Laguna del Hunco paleoflora and extant subtropical and tropical Australasia, one of the three major ecologic-geographic elements of the Laguna del Hunco paleoflora. The age and affinities of the fossils also indicate that Eucalyptus subgenus Symphyomyrtus is older than previously supposed. Paleoecological data

  9. Water stress and recovery in the performance of two Eucalyptus globulus clones: physiological and biochemical profiles.

    Science.gov (United States)

    Correia, Barbara; Pintó-Marijuan, Marta; Neves, Lucinda; Brossa, Ricard; Dias, Maria Celeste; Costa, Armando; Castro, Bruno B; Araújo, Clara; Santos, Conceição; Chaves, Maria Manuela; Pinto, Glória

    2014-04-01

    Eucalyptus plantations are among the most productive forest stands in Portugal and Spain, being mostly used for pulp production and, more recently, as an energy crop. However, the region's Mediterranean climate, with characteristic severe summer drought, negatively affects eucalypt growth and increases mortality. Although the physiological response to water shortage is well characterized for this species, evidence about the plants' recovery ability remains scarce. In order to assess the physiological and biochemical response of Eucalyptus globulus during the recovery phase, two genotypes (AL-18 and AL-10) were submitted to a 3-week water stress period at two different intensities (18 and 25% of field capacity), followed by 1 week of rewatering. Recovery was assessed 1 day and 1 week after rehydration. Drought reduced height, biomass, water potential, NPQ and gas exchange in both genotypes. Contrarily, the levels of pigments, chlorophyll fluorescence parameters (F(v) /F(m) and (φPSII)), MDA and ABA increased. During recovery, the physiological and biochemical profile of stressed plants showed a similar trend: they experienced reversion of altered traits (MDA, ABA, E, g(s), pigments), while other parameters did not recover ((φPSII), NPQ). Furthermore, an overcompensation of CO(2) assimilation was achieved 1 week after rehydration, which was accompanied by greater growth and re-establishment of oxidative balance. Both genotypes were tolerant to the tested conditions, although clonal differences were found. AL-10 was more productive and showed a more rapid and dynamic response to rehydration (namely in carotenoid content, (φPSII) and NPQ) compared to clone AL-18. © 2013 Scandinavian Plant Physiology Society.

  10. Contrasting nitrogen fertilization treatments impact xylem gene expression and secondary cell wall lignification in Eucalyptus.

    Science.gov (United States)

    Camargo, Eduardo Leal Oliveira; Nascimento, Leandro Costa; Soler, Marçal; Salazar, Marcela Mendes; Lepikson-Neto, Jorge; Marques, Wesley Leoricy; Alves, Ana; Teixeira, Paulo José Pereira Lima; Mieczkowski, Piotr; Carazzolle, Marcelo Falsarella; Martinez, Yves; Deckmann, Ana Carolina; Rodrigues, José Carlos; Grima-Pettenati, Jacqueline; Pereira, Gonçalo Amarante Guimarães

    2014-09-28

    Nitrogen (N) is a main nutrient required for tree growth and biomass accumulation. In this study, we analyzed the effects of contrasting nitrogen fertilization treatments on the phenotypes of fast growing Eucalyptus hybrids (E. urophylla x E. grandis) with a special focus on xylem secondary cell walls and global gene expression patterns. Histological observations of the xylem secondary cell walls further confirmed by chemical analyses showed that lignin was reduced by luxuriant fertilization, whereas a consistent lignin deposition was observed in trees grown in N-limiting conditions. Also, the syringyl/guaiacyl (S/G) ratio was significantly lower in luxuriant nitrogen samples. Deep sequencing RNAseq analyses allowed us to identify a high number of differentially expressed genes (1,469) between contrasting N treatments. This number is dramatically higher than those obtained in similar studies performed in poplar but using microarrays. Remarkably, all the genes involved the general phenylpropanoid metabolism and lignin pathway were found to be down-regulated in response to high N availability. These findings further confirmed by RT-qPCR are in agreement with the reduced amount of lignin in xylem secondary cell walls of these plants. This work enabled us to identify, at the whole genome level, xylem genes differentially regulated by N availability, some of which are involved in the environmental control of xylogenesis. It further illustrates that N fertilization can be used to alter the quantity and quality of lignocellulosic biomass in Eucalyptus, offering exciting prospects for the pulp and paper industry and for the use of short coppices plantations to produce second generation biofuels.

  11. Comparative pulping of sunflower stalks

    Directory of Open Access Journals (Sweden)

    Valerii Barbash

    2016-03-01

    Full Text Available The procedure of holocellulose content determination in non-wood plant raw materials was developed. The strength properties of pulp obtained from sunflower stalks by neutral-sulphite, soda, alkaline sulphite-anthraquinone-ethanol and peracetic methods of delignification were studied. Methodology of comparison of plant materials delignification methods using new lignin-carbohydrate diagram was proposed. It was shown, that the alkaline sulphite-anthraquinone-ethanol method of pulping is characterized by the highest delignification degree and is the most efficient among the studied methods

  12. Effet de l'hybridation interspecifique sur la teneur et la composition chimique des huiles essentielles d'eucalyptus cultivés au Maroc

    OpenAIRE

    Farah A.; Fechtal M.; Chaouch A.

    2002-01-01

    Interspecific hybridization effect on the content and the chemical composition of essential oils of eucalyptus grown in Morocco. In this work, the quality and quantity of the leave essential oils of five Eucalyptus hybrids were determined. The crosses of Eucalyptus globulus ssp. maideni, Eucalyptus globulus ssp. globulus, Eucalyptus grandis, Eucalyptus cladocalyx and Eucalyptus diversicolor with Eucalyptus camaldulensis have been studied. The average yield of parental species samples varies a...

  13. The presence of some artificial and natural radionuclides in a Eucalyptus forest in the south of Spain

    International Nuclear Information System (INIS)

    Vaca, F.; Manjon, G.; Garcia-Leon, M.

    2001-01-01

    Long-lived artificial radionuclides ( 137 Cs, 90 Sr) were studied in a Eucalyptus plantation located in the south-west of Spain. Radionuclide concentrations were determined in different types of samples corresponding to specific forest components (soil, trees, herbs and litter). Depth profile distributions were obtained in two selected core soils. Two layers were separately measured in three other cores. The concentration factor, defined as the ratio between the mean activity concentration in a component and the mean activity concentration in the soil, was calculated for each component. The biomass of different components was estimated in order to evaluate the total density concentration (Bq/ha) of the artificial radionuclides ( 137 Cs, 90 Sr) in the Eucalyptus plantation. The transfer of the radionuclides between the different forest components can be inferred from the results. Additionally, other naturally occurring radionuclides ( 40 K, 226 Ra, 228 Ra, 228 Ac) were determined for comparison. Transport of radionuclides from forest to a nearby pulp mill is also discussed

  14. PEMUTIHAN PULP DENGAN HIDROGEN PEROKSIDA

    Directory of Open Access Journals (Sweden)

    Ahmad M. Fuadi

    2012-01-01

    Full Text Available The use of bleaching agent has increased as the result of increasing of paper consumption. The conventional bleaching agent that commonly used is material containing of chlorine. This material is not environmentally friendly and should be replaced by environmentally benign chemical, such as H2O2. About 40 gram of dry Akasia pulp was mixed with 600 ml of distilled water was put into plastic bag heated in a water bath. When the temperature reached 630C, a solution of 4 % of H2O2 and distilled water was added to obtain 5 % consistency. This mixture was put into water bath and was heated for 2 hours. The same procedure was conducted with various concentration of H2O2, time and pH. At the end of the process, the pulp was dewatered and washed. The filtrate obtained from the initial dewatering was used to determine the residual of H2O2. The pulp was analyzed to determine brightness, fiber strength and kappa number. The maximum achievement of brightness was 62,1 % ISO, 6.86 of kappa number and 1.02 kg/15 mm of fiber strength, which are reached at16 % of the use of H2O2, pH 11 and 5 hours of bleaching time. This achievement is similar to bleaching result by the additional of 4% H2O2. Inefficient usage of H2O2 was caused by some metal ions in the pulp which facilitate the decomposition of H2O2 to produce oxygen and water which has not effect on increasing the brightness. To improve the bleach ability of H2O2, initial treatment to remove metal ions from pulp should be done. Seiring dengan meningkatnya kebutuhan kertas, kebutuhan bahan pemutih juga mengalami kenaikan. Saat ini bahan pemutih yang banyak digunakan adalah senyawa yang mengandung khlor. Senyawa ini sangat tidak ramah lingkungan, oleh karena itu, perlu dicari bahan yang ramah lingkungan untuk menggantikannya. Salah satunya adalah hidrogen peroksida. Pulp dari pohon akasia sebanyak 40 gram kering dicampur dengan 600 ml aquadest dimasukkan dalam kantung plastik dipanaskan dalam water bath

  15. Properties of particleboards fabricated with eucalyptus (Eucalyptus urophylla, parica (Schizolobium amazonicum and vassoura (Sida spp. particles

    Directory of Open Access Journals (Sweden)

    Juliana Jerásio Bianche

    2012-12-01

    Full Text Available The genus Sida may become a promising alternative source for the production of particleboards. Nowadays it is used for manufacturing ropes due to the quality of its fibers, however, there is no research relating the production of particleboards using this lignocelluloses material. This study aimed to evaluate the effect of eucalyptus (Eucalyptus urophylla, paricá (Schizolobium amazonicum and vassoura (Sida spp. on the physical and mechanical properties of particleboard. Particleboard contained 25, 50, 75 and 100% of eucalyptus and paricá or eucalytus and vassoura or paricá an vassoura were fabricated. Two (6% and 8% amounts of urea-formaldehyde adhesive were used. The physical and mechanical properties were determined according to NBR / ABNT 14810-3 (ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS - ABNT, 2002. It was observed that increase in resin content in the improved some physical and mechanical properties. It was concluded that the amount of vassoura particles on panels had different effects depending on the species used. The increase in the percentage of vassoura particles in the Eucalyptus panels did not affect the internal bond, screw withdrawal and hardness. Increasing the percentage of vassoura particles on the panels produced with paricá did not affect its hardness and resistance to screw withdrawal. The panels produced with vassoura particle absorbed more water and, consequently, increased the thickness swelling, and therefore is not recommended for use in environments with high humidity. It was concluded that the genus Sida, in general, has potential for particleboard production.

  16. Modeling and optimization of extraction process of eucalyptus essential oil (Eucalyptus globulus)

    OpenAIRE

    Jeancarlos Moreno; Gabriel López; Raúl Siche

    2010-01-01

    In this paper we have studied the effect of the moisture from the eucalyptus leaf and the time of extraction on the yield of essential oil and the production cost. We took into account parameters such as steam temperature, pressure extraction, porous bed, steam flow and temperature of condensation. A Central Composite Rotational Design was used to evaluate optimum extraction areas and the cost that would follow, searching always to increase yields and reduce costs. According to this design, t...

  17. Genetic mapping in Eucalyptus urophylla and Eucalyptus grandis using RAPD markers.

    Science.gov (United States)

    Verhaegen, D; Plomion, C

    1996-12-01

    Two single-tree linkage maps were constructed for Eucalyptus urophylla and Eucalyptus grandis, based on the segregation of 480 random amplified polymorphic DNA (RAPD) markers in a F1 interspecific progeny. A mixture of three types of single-locus segregations were observed: 244 1:1 female, 211 1:1 male, and 25 markers common to both, segregating 3:1. Markers segregating in the 1:1 ratio (testcross loci) were used to establish separate maternal and paternal maps, while markers segregating in the 3:1 ratio were used to identify homology between linkage groups of the two species maps. An average of 2.8 polymorphic loci were mapped for each arbitrary decamer primer used in the polymerase chain reaction. The mean interval size beween framework markers on the maps was 14 cM. The maps comprised 269 markers covering 1331 cM and 236 markers covering 1415 cM, in 11 linkage groups, for E. urophylla (2n = 2x = 22) and E. grandis (2n = 2x = 22), respectively. A comparative mapping analysis with two other E. urophylla and E. grandis linkage maps showed that RAPDs could be reliable markers for establishing a consensus species map. RAPD markers were automatically and quantitatively scored with an imaging analyzer. They were classified into four categories based on their optical density. A fragment intensity threshold is proposed to optimize the selection of reliable RAPD markers for future mapping experiments. Key words : genetic linkage map, Eucalyptus urophylla, Eucalyptus grandis, random amplified polymorphic DNA, RAPD, automated data collection.

  18. [Chronobiology of pulp sensibility in young people].

    Science.gov (United States)

    Guo, Bin; Xu, Zhen; Chen, Xiu-Mei; Wang, Qing-Qing; Xie, Si-Jing; Zhang, Qiong; Zhou, Xue-Dong

    2005-11-01

    To explore the biological clock of pulp sensibility in young people so as to enrich the theory of pulp-chronobiology and conduce to clinical diagnosis and the treatment of pulposis. 40 healthy young volunteers (20 males and 20 females) were examined. Pulp sensibility test was performed using the pulp sensibility tester produced in France. Pulp sensibility reading was obtained at each 4 hours from 8:00 a.m. till next 8:00 a.m., thus there were totally seven time-pints in 24 hours. And the readings were averaged. The pulp sensibility data of every volunteer were analyzed by methods for cosinor-rhythmometry, and significant difference (P 0.05). Circadian rhythm is demonstrated in thepulp sensibility data of young people; the highest pulp sensibility is at 12:00 while the lowest is at 0:00.

  19. Effect of organosolv and soda pulping processes on the metals content of non-woody pulps.

    Science.gov (United States)

    González, M; Cantón, L; Rodríguez, A; Labidi, J

    2008-09-01

    In this work the effect of different pulping processes (ethyleneglycol, diethyleneglycol, ethanolamine and soda) of tow abounded raw materials (empty fruit bunches - EFB and rice straw) on the ash, silicates and metals (Fe, Zn, Cu, Pb, Mn, Ni and Cd) content of the obtained pulps have been studied. Results showed that pulps obtained by diethyleneglycol pulping process presented lower metals content (756 microg/g and 501 microg/g for EFB and rice straw pulp, respectively) than soda pulps (984 microg/g and 889 microg/g). Ethanolamine pulps presented values of holocellulose (74% and 77% for EFB and rice straw pulp, respectively), alpha-cellulose (74% and 69%), kappa number (18.7 and 18.5) and viscosity (612 and 90 6ml/g) similar to those of soda pulp, and lower lignin contents (11% and 12%).

  20. Leaf water relations of Eucalyptus cloeziana and Eucalyptus argophloia in response to water deficit.

    Science.gov (United States)

    Ngugi, Michael R; Doley, David; Hunt, Mark A; Dart, Peter; Ryan, Paul

    2003-04-01

    Leaf water relations responses to limited water supply were determined in 7-month-old plants of a dry inland provenance of Eucalyptus argophloia Blakely and in a humid coastal provenance (Gympie) and a dry inland provenance (Hungry Hills) of Eucalyptus cloeziana F. Muell. Each provenance of E. cloeziana exhibited a lower relative water content at the turgor loss point, a lower apoplastic water content, a smaller ratio of dry mass to turgid mass and a lower bulk modulus of elasticity than the single provenance of E. argophloia. Osmotic potential at full turgor and water potential at the turgor loss point were significantly lower in E. argophloia and the inland provenance of E. cloeziana than in the coastal provenance of E. cloeziana. There was limited osmotic adjustment in response to soil drying in E. cloeziana, but not in E. argophloia. Between-species differences in water relations parameters were larger than those between the E. cloeziana provenances. Both E. cloeziana provenances maintained turgor under moderate water stress through a combination of osmotic and elastic adjustments. Eucalyptus argophloia had more rigid cell walls and reached lower water potentials with less reduction in relative water content than either of the E. cloeziana provenances, thereby enabling it to extract water from dryer soils.

  1. Energy evaluation of the Eucalyptus globulus and the Eucalyptus nitens in the north of Spain (Cantabria)

    Energy Technology Data Exchange (ETDEWEB)

    Perez, S.; Renedo, C.J.; Ortiz, A.; Manana, M.; Silio, D. [Electrical and Energy Engineering Department, University of Cantabria, 39005 Santander (Spain)

    2006-12-01

    This work studied the potential use of the waste from Eucalyptus globulus and Eucalyptus nitens as energy crops, evaluating young and adult stages of both in all four seasons of the year with different moisture contents. The study was carried out made in Cantabria (North coast of Spain), located at latitude 43{sup o}28'N, and longitude 3{sup o}48'W. In this region, 29,513ha are dedicated to the growth of Eucalyptus, with about 80% E. globulus, and 20% E. nitens. Six different plantations have been analyzed and their bioclimatic diagrams determined. After the collection of samples the potential energy of every sample was obtained, they were weighed, analyzed and burned, giving a mean net calorific value of 17,384 and 17,927kJ/kg in the adult stage of E. globulus and E. nitens, respectively. The results for the young stage of both species were 17,708 and 18,670kJ/kg. Moisture content in the samples has a great influence on power production. Finally, the economic and environmental consequences of these crop species for the region of Cantabria were analyzed. (author)

  2. Insights into temperature modulation of the Eucalyptus globulus and Eucalyptus grandis antioxidant and lignification subproteomes.

    Science.gov (United States)

    de Santana Costa, Marília Gabriela; Mazzafera, Paulo; Balbuena, Tiago Santana

    2017-05-01

    Eucalyptus grandis and Eucalyptus globulus are among the most widely cultivated trees, differing in lignin composition and plantation areas, as E. grandis is mostly cultivated in tropical regions while E. globulus is preferred in temperate areas. As temperature is a key modulator in plant metabolism, a large-scale proteome analysis was carried out to investigate changes in the antioxidant system and the lignification metabolism in plantlets grown at different temperatures. Our strategy allowed the identification of 3111 stem proteins. A total of 103 antioxidant proteins were detected in the stems of both species. Hierarchical clustering revealed that alterations in the antioxidant proteins are more prominent when Eucalyptus seedlings were exposed to high temperature and that the superoxide isoforms coded by the gene Eucgr.B03930 are the most abundant antioxidant enzymes induced by thermal stimulus. Regarding the lignin biosynthesis, our proteomics approach resulted in the identification of 13 of the 17 core proteins involved in this metabolism, corroborating with gene predictions and the proposed lignin toolbox. Quantitative analyses revealed significant differences in 8 protein isoforms, including the ferulate 5-hydroxylase isoform F5H1, a key enzyme in catalyzing the synthesis of sinapyl alcohol, and the cinnamyl alcohol dehydrogenase isoform CAD2, the last enzyme in monolignol biosynthesis. Data are available via ProteomeXchange with identifier PXD005743. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Energy evaluation of the Eucalyptus globulus and the Eucalyptus nitens in the north of Spain (Cantabria)

    International Nuclear Information System (INIS)

    Perez, S.; Renedo, C.J.; Ortiz, A.; Manana, M.; Silio, D.

    2006-01-01

    This work studied the potential use of the waste from Eucalyptus globulus and Eucalyptus nitens as energy crops, evaluating young and adult stages of both in all four seasons of the year with different moisture contents. The study was carried out made in Cantabria (North coast of Spain), located at latitude 43 o 28'N, and longitude 3 o 48'W. In this region, 29,513ha are dedicated to the growth of Eucalyptus, with about 80% E. globulus, and 20% E. nitens. Six different plantations have been analyzed and their bioclimatic diagrams determined. After the collection of samples the potential energy of every sample was obtained, they were weighed, analyzed and burned, giving a mean net calorific value of 17,384 and 17,927kJ/kg in the adult stage of E. globulus and E. nitens, respectively. The results for the young stage of both species were 17,708 and 18,670kJ/kg. Moisture content in the samples has a great influence on power production. Finally, the economic and environmental consequences of these crop species for the region of Cantabria were analyzed. (author)

  4. High-resolution genetic maps of Eucalyptus improve Eucalyptus grandis genome assembly.

    Science.gov (United States)

    Bartholomé, Jérôme; Mandrou, Eric; Mabiala, André; Jenkins, Jerry; Nabihoudine, Ibouniyamine; Klopp, Christophe; Schmutz, Jeremy; Plomion, Christophe; Gion, Jean-Marc

    2015-06-01

    Genetic maps are key tools in genetic research as they constitute the framework for many applications, such as quantitative trait locus analysis, and support the assembly of genome sequences. The resequencing of the two parents of a cross between Eucalyptus urophylla and Eucalyptus grandis was used to design a single nucleotide polymorphism (SNP) array of 6000 markers evenly distributed along the E. grandis genome. The genotyping of 1025 offspring enabled the construction of two high-resolution genetic maps containing 1832 and 1773 markers with an average marker interval of 0.45 and 0.5 cM for E. grandis and E. urophylla, respectively. The comparison between genetic maps and the reference genome highlighted 85% of collinear regions. A total of 43 noncollinear regions and 13 nonsynthetic regions were detected and corrected in the new genome assembly. This improved version contains 4943 scaffolds totalling 691.3 Mb of which 88.6% were captured by the 11 chromosomes. The mapping data were also used to investigate the effect of population size and number of markers on linkage mapping accuracy. This study provides the most reliable linkage maps for Eucalyptus and version 2.0 of the E. grandis genome. © 2014 CIRAD. New Phytologist © 2014 New Phytologist Trust.

  5. Kajian Beberapa Sifat Dasar Kayu Ekaliptus (Eucalyptus grandis) Umur 5 Tahun

    OpenAIRE

    Hutagalung, Frans Januari

    2011-01-01

    This study aimed to evaluate the nature of anatomical, physical, and mechanical eucalyptus wood (Eucalyptus grandis), age 5 years vertically and horizontally. The nature of eucalyptus wood anatomy shows that shaped pores solitary and multiple 2-3, eucalyptus stems reddish brown wood, eucalyptus wood looks dull and the direction of the fiber straight to wavy. Eucalyptus wood fiber length average 1103.53 μ, fiber diameter 282.4 μ, lumen diameter 188 μ, and fiber wall thickness 47.2 μ. The physi...

  6. Characterization of endo-β-mannanase from Enterobacter ludwigii MY271 and application in pulp industry.

    Science.gov (United States)

    Yang, Miao; Cai, Jun; Wang, Changgao; Du, Xin; Lin, Jianguo

    2017-01-01

    β-Mannanases are the second most important enzymes for the hydrolysis of hemicelluloses. An endo-β-mannanase from Enterobacter ludwigii MY271 was purified at 11.7 ± 0.2-fold to homogeneity with a final recovery of 15.2 ± 0.2 %. Using purified β-mannanase protein and SDS-PAGE, the molecular mass was found to be 43.16 kDa. The optimal pH and temperature of the enzyme was found to be 7.0 and 55 °C, respectively. The β-mannanase activity was stable over a broad pH range of pH 2.0-10.0. In addition, the purified enzyme was highly activated by several metal ions and chemical reagents, such as Mg 2+ , L-cysteine, glutathione (GSH) and β-mercaptoethanol. Whereas the enzyme was strongly inhibited by Hg 2+ , Cu 2+ , N-bromosuccinimide (NBS), 1-ethyl-3-(3-dimethyl-amino-propyl)-carbodiimide (EDC), phenylmethanesulfonyl fluoride (PMSF), and sodium dodecyl sulfate (SDS). The β-mannanase was highly active towards glucomannan, and showed endo-activity by producing a mixture of oligosaccharides. Moreover, the enzyme displayed a classical endo-type mode on mannooligosaccharides. The β-mannanase coupled with xylanase significantly improved the brightness of kraft pulp, whereas it has no remarkable effect on the tensile strength of the pulp. Our functional studies of the purified β-mannanase indicate that the enzyme is beneficial to industrial applications, in particular, biotechnological processes, such as food, feed and pulp industry.

  7. Pulp regeneration: Current approaches and future challenges

    Directory of Open Access Journals (Sweden)

    Jingwen eYANG

    2016-03-01

    Full Text Available Regenerative endodontics aims to replace inflamed/necrotic pulp tissues with regenerated pulp-like tissues to revitalize teeth and improve life quality. Pulp revascularization case reports, which showed successful clinical and radiographic outcomes, indicated the possible clinical application of pulp regeneration via cell homing strategy. From a clinical point of view, functional pulp-like tissues should be regenerated with the characterization of vascularization, re-innervation, and dentin deposition with a regulated rate similar to that of normal pulp. Efficient root canal disinfection and proper size of the apical foramen are the two requisite preconditions for pulp regeneration. Progress has been made on pulp regeneration via cell homing strategies. This review focused on the requisite preconditions and cell homing strategies for pulp regeneration. In addition to the traditionally used mechanical preparation and irrigation, antibiotics, irrigation assisted with EndoVac apical negative-pressure system, and ultrasonic and laser irradiation are now being used in root canal disinfection. In addition, pulp-like tissues could be formed with the apical foramen less than 1 mm, although more studies are needed to determine the appropriate size. Moreover, signaling molecules including stromal cell derived factor (SDF-1α, basic Fibroblast Growth Factor (bFGF, Platelet Derived Growth Factor (PDGF, stem cell factor (SCF, and Granulocyte Colony-Stimulating Factor (G-CSF were used to achieve pulp-like tissue formation via a cell homing strategy. Studies on the cell sources of pulp regeneration might give some indications on the signaling molecular selection. The active recruitment of endogenous cells into root canals to regenerate pulp-like tissues is a novel concept that may offer an unprecedented opportunity for the near-term clinical translation of current biology-based therapies for dental pulp regeneration.

  8. Chemical composition and fumigant toxicity of the essential oils from 16 species of Eucalyptus against Haematobia irritans (Diptera: Muscidae) adults.

    Science.gov (United States)

    Juan, Laura W; Lucia, Alejandro; Zerba, Eduardo N; Harrand, Leonel; Marco, Martin; Masuh, Hector M

    2011-06-01

    Oils extracted from various species of Eucalyptus (Eucalyptus badjensis Beuzev & Welch, Eucalyptus badjensis x Eucalyptus nitens, Eucalyptus benthamii variety dorrigoensis Maiden & Cambage, Eucalyptus botryoides Smith, Eucalyptus dalrympleana Maiden, Eucalyptus fastigata Deane & Maiden, Eucalyptus nobilis L.A.S. Johnson & K. D. Hill, Eucalyptus polybractea R. Baker, Eucalyptus radiata ssp. radiata Sieber ex Spreng, Eucalyptus resinifera Smith, Eucalyptus robertsonii Blakely, Eucalyptus rubida Deane & Maiden, Eucalyptus smithii R. Baker, Eucalyptus elata Dehnh, Eucalyptus fraxinoides Deane & Maiden, E. obliqua L'Hér) were obtained by hydrodistillation. The chemical composition of essential oils was determined by gas chromatography coupled to mass spectrometry. Essential oils were mainly composed of 1,8-cineole, alpha-pinene, alpha-terpineol, 4-terpineol, and p-cymene. Vapors from these essential oils and their major components were found to be toxic to Haematobia irritans (L.) (Diptera: Muscidae) adults. An aliquot of each oil was placed in a cylindrical test chamber, and the number of knocked down flies was recorded as a function of time. Knockdown time 50% was then calculated. Results showed that essential oil of E. polybractea had the highest knockdown activity of 3.44 min. A correlation was observed between the content of 1,8-cineole in the Eucalyptus essential oils and the corresponding toxic effect.

  9. Signaling Molecules and Pulp Regeneration.

    Science.gov (United States)

    Schmalz, Gottfried; Widbiller, Matthias; Galler, Kerstin M

    2017-09-01

    Signaling molecules play an essential role in tissue engineering because they regulate regenerative processes. Evidence exists from animal studies that single molecules such as members of the transforming growth factor beta superfamily and factors that induce the growth of blood vessels (vascular endothelial growth factor), nerves (brain-derived neurotrophic factor), or fibroblasts (fibroblast growth factor) may induce reparative dentin formation. Mainly the formation of atubular dentin (osteodentin) has been described after the application of single molecules or combinations of recombinant growth factors on healthy exposed pulps or in pulp regeneration. Generally, such preparations have not received regulatory approval on the market so far. Only the use of granulocyte colony-stimulating factors together with cell transplantation is presently tested clinically. Besides approaches with only 1 or few combined molecules, the exploitation of tissue-derived growth factors depicts a third promising way in dental pulp tissue engineering. Preparations such as platelet-rich plasma or platelet-rich fibrin provide a multitude of endogenous signaling molecules, and special regulatory approval for the market does not seem necessary. Furthermore, dentin is a perfect reservoir of signaling molecules that can be mobilized by treatment with demineralizing agents such as EDTA. This conditions the dentin surface and allows for contact differentiation of pulp stem cells into odontoblastlike cells, protects dentin from resorption, and enhances cell growth as well as attachment to dentin. By ultrasonic activation, signaling molecules can be further released from EDTA pretreated dentin into saline, thus avoiding cytotoxic EDTA in the final preparation. The use of dentin-derived growth factors offers a number of advantages because they are locally available and presumably are most fit to induce signaling processes in dental pulp. However, better characterization and standardization of the

  10. Expression profiling and gene ontology analysis in fathead minnow (Pimephales promelas) liver following exposure to pulp and paper mill effluents

    International Nuclear Information System (INIS)

    Costigan, Shannon L.; Werner, Julieta; Ouellet, Jacob D.; Hill, Lauren G.; Law, R. David

    2012-01-01

    Many studies link pulp and paper mill effluent (PPME) exposure to adverse effects in fish populations present in the mill receiving environments. These impacts are often characteristic of endocrine disruption and may include impaired reproduction, development and survival. While these physiological endpoints are well-characterized, the molecular mechanisms causing them are not yet understood. To investigate changes in gene transcription induced by exposure to a PPME at several stages of treatment, male and female fathead minnows (FHMs) were exposed for 6 days to 25% (v/v) secondary (biologically) treated kraft effluent (TK) or 100% (v/v) combined mill outfall (CMO) from a mill producing both kraft pulp and newsprint. The gene expression changes in the livers of these fish were analyzed using a 22 K oligonucleotide microarray. Exposure to TK or CMO resulted in significant changes in the expression levels of 105 and 238 targets in male FHMs and 296 and 133 targets in females, respectively. Targets were then functionally analyzed using gene ontology tools to identify the biological processes in fish hepatocytes that were affected by exposure to PPME after its secondary treatment. Proteolysis was affected in female FHMs exposed to both TK and CMO. In male FHMs, no processes were affected by TK exposure, while sterol, isoprenoid, steroid and cholesterol biosynthesis and electron transport were up-regulated by CMO exposure. The results presented in this study indicate that short-term exposure to PPMEs affects the expression of reproduction-related genes in the livers of both male and female FHMs, and that secondary treatment of PPMEs may not neutralize all of their metabolic effects in fish. Gene ontology analysis of microarray data may enable identification of biological processes altered by toxicant exposure and thus provide an additional tool for monitoring the impact of PPMEs on fish populations.

  11. Expression profiling and gene ontology analysis in fathead minnow (Pimephales promelas) liver following exposure to pulp and paper mill effluents

    Energy Technology Data Exchange (ETDEWEB)

    Costigan, Shannon L.; Werner, Julieta; Ouellet, Jacob D.; Hill, Lauren G. [Department of Biology, Lakehead University, 955 Oliver Road, Ontario P7B 5E1, (Canada); Law, R. David, E-mail: dlaw@lakeheadu.ca [Department of Biology, Lakehead University, 955 Oliver Road, Ontario P7B 5E1, (Canada)

    2012-10-15

    Many studies link pulp and paper mill effluent (PPME) exposure to adverse effects in fish populations present in the mill receiving environments. These impacts are often characteristic of endocrine disruption and may include impaired reproduction, development and survival. While these physiological endpoints are well-characterized, the molecular mechanisms causing them are not yet understood. To investigate changes in gene transcription induced by exposure to a PPME at several stages of treatment, male and female fathead minnows (FHMs) were exposed for 6 days to 25% (v/v) secondary (biologically) treated kraft effluent (TK) or 100% (v/v) combined mill outfall (CMO) from a mill producing both kraft pulp and newsprint. The gene expression changes in the livers of these fish were analyzed using a 22 K oligonucleotide microarray. Exposure to TK or CMO resulted in significant changes in the expression levels of 105 and 238 targets in male FHMs and 296 and 133 targets in females, respectively. Targets were then functionally analyzed using gene ontology tools to identify the biological processes in fish hepatocytes that were affected by exposure to PPME after its secondary treatment. Proteolysis was affected in female FHMs exposed to both TK and CMO. In male FHMs, no processes were affected by TK exposure, while sterol, isoprenoid, steroid and cholesterol biosynthesis and electron transport were up-regulated by CMO exposure. The results presented in this study indicate that short-term exposure to PPMEs affects the expression of reproduction-related genes in the livers of both male and female FHMs, and that secondary treatment of PPMEs may not neutralize all of their metabolic effects in fish. Gene ontology analysis of microarray data may enable identification of biological processes altered by toxicant exposure and thus provide an additional tool for monitoring the impact of PPMEs on fish populations.

  12. Activités antimicrobiennes des huiles essentielles de Eucalyptus ...

    African Journals Online (AJOL)

    Les huiles essentielles de Eucalyptus citriodora et Eucalyptus houseana récoltées à N'Débougou (Mali) ont été testées sur les bactéries Escherichia coli, Staphylococcus aureus et le champignon Candida albicans. Nous avons utilisé la méthode de diffusion en Agar pour de la détermination des activités antibactériennes.

  13. Methanol production from Eucalyptus wood chips. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fishkind, H.H.

    1982-06-01

    This feasibility study includes all phases of methanol production from seedling to delivery of finished methanol. The study examines: production of 55 million, high quality, Eucalyptus seedlings through tissue culture; establishment of a Eucalyptus energy plantation on approximately 70,000 acres; engineering for a 100 million gallon-per-day methanol production facility; potential environmental impacts of the whole project; safety and health aspects of producing and using methanol; and development of site specific cost estimates.

  14. Characterization of eucalyptus clones subject to wind damage

    OpenAIRE

    Zanuncio, Antônio José Vinha; Carvalho, Amélia Guimarães; Carneiro, Angélica de Cassia Oliveira; Valenzuela, Paulina; Gacitúa, William; Leite, Fernando Palha; Colodette, Jorge Luiz

    2017-01-01

    Abstract: The objective of this work was to test a new methodology to assess the resistance of trees to wind damage and determine the characteristics that increase clone resistance to winds. Tree resistance to breakage, basic density, ultrastructure, anatomy, mechanical properties, and wood growth stress have been evaluated in seven Eucalyptus grandis × Eucalyptus urophylla clones, collected from a region with a high incidence of wind damage. The Pearson correlation coefficient between the tr...

  15. Monoterpene and isoprene emissions from 15 Eucalyptus species in Australia

    Science.gov (United States)

    He, Congrong; Murray, Frank; Lyons, Tom

    Monoterpene and isoprene emission rates of 15 Eucalyptus species were measured using an air exchange chamber technique and GC-FID analysis. The normalised monoterpene emission rates (leaf temperature 30°C) of these Eucalyptus species ranged from zero for E. forrestiana to 5.4±2.2 μg g -1 h -1 (or 871±33 μg m -2 h -1) for E. globulus. The dominant monoterpene compounds emitted from these Eucalyptus species were α-pinene, 1,8-cineole, β-pinene and limonene. The normalised isoprene emission rates (leaf temperature 30°C, PAR flux 1000 μmol m -2 s -1) ranged from 5.3±1.6 ( E. botryoides) to 69±34 μg g -1 h -1 ( E. globulus) or from 0.74 ( E. cladocalyx) to 9.5 mg m -2 h -1 ( E. rudis). Based on monoterpene emission rate data from four Eucalyptus species ( E. globulus, E. robusta, E. rudis, and E. sargentii), there were clear exponential relationships between leaf temperature and monoterpene emission rate for these Eucalyptus species. The mean exponential value ( β value) of the four Eucalyptus species was 0.103±0.012 K -1.

  16. WEED CONTROL AND BORON NUTRITION ON Eucalyptus IN SILVOPASTORAL SYSTEM

    Directory of Open Access Journals (Sweden)

    Alexandre Magno Brighenti

    2015-04-01

    Full Text Available The objective of this study was to evaluate the control of weeds in the rows of eucalyptus (Eucalyptus urograndis with herbicides applied singly or combined with boron (B, as well as, the response of Eucalyptus plants to this micronutrient. The experiments were carried out in a split-plot with randomized complete block design, with three replicates. Six treatments were applied to the plots: (i weeded control, (ii control without weeding, (iii glyphosate (1080 g ae ha-1 + chlorimuron-ethyl (10 g ai ha-1 + 0.05% v / v mineral oil, (iv glyphosate (1080 g ae  ha-1 + isoxaflutole (112.5 g ai ha-1,  (v glyphosate (1080 g ae ha-1 and  (vi oxyfluorfen (480 g ai ha-1. The sub-plots consisted of the absence or presence of 4 kg of boric acid (H3BO3 - 17% B in 100 L of water. The addition of boric acid in the solution containing the herbicides did not affect the weed control. There was an increase in boron content in the soil and consequently an increase in the boron levels in the eucalyptus leaves. The combined application of herbicides plus boric acid is perfectly suitable for preventing dry of the pointer on eucalyptus plants. Keywords: Eucalyptus urograndis; chemical control; herbicides; micronutrients; Urochloa decumbens.

  17. Integration of the Mini-Sulfide Sulfite Anthraquinone (MSS-AQ) Pulping Process and Black Liquor Gasification in a Pulp Mill

    Energy Technology Data Exchange (ETDEWEB)

    Hasan Jameel, North Carolina State University; Adrianna Kirkman, North Carolina State University; Ravi Chandran,Thermochem Recovery International Brian Turk Research Triangle Institute; Brian Green, Research Triangle Institute

    2010-01-27

    As many of the recovery boilers and other pieces of large capital equipment of U.S. pulp mills are nearing the end of their useful life, the pulp and paper industry will soon need to make long-term investments in new technologies. The ability to install integrated, complete systems that are highly efficient will impact the industry’s energy use for decades to come. Developing a process for these new systems is key to the adoption of state-of-the-art technologies in the Forest Products industry. This project defined an integrated process model that combines mini-sulfide sulfite anthraquinone (MSS-AQ) pulping and black liquor gasification with a proprietary desulfurization process developed by the Research Triangle Institute. Black liquor gasification is an emerging technology that enables the use of MSS-AQ pulping, which results in higher yield, lower bleaching cost, lower sulfur emissions, and the elimination of causticization requirements. The recently developed gas cleanup/absorber technology can clean the product gas to a state suitable for use in a gas turbine and also regenerate the pulping chemicals needed to for the MSS-AQ pulping process. The combination of three advanced technologies into an integrated design will enable the pulping industry to achieve a new level of efficiency, environmental performance, and cost savings. Because the three technologies are complimentary, their adoption as a streamlined package will ensure their ability to deliver maximum energy and cost savings benefits. The process models developed by this project will enable the successful integration of new technologies into the next generation of chemical pulping mills. When compared to the Kraft reference pulp, the MSS-AQ procedures produced pulps with a 10-15 % yield benefit and the ISO brightness was 1.5-2 times greater. The pulp refined little easier and had a slightly lower apparent sheet density (In both the cases). At similar levels of tear index the MSS-AQ pulps also

  18. Characterization and genomic analysis of kraft lignin biodegradation by the beta-proteobacterium Cupriavidus basilensis B-8

    Directory of Open Access Journals (Sweden)

    Shi Yan

    2013-01-01

    Full Text Available Abstract Background Lignin materials are abundant and among the most important potential sources for biofuel production. Development of an efficient lignin degradation process has considerable potential for the production of a variety of chemicals, including bioethanol. However, lignin degradation using current methods is inefficient. Given their immense environmental adaptability and biochemical versatility, bacterial could be used as a valuable tool for the rapid degradation of lignin. Kraft lignin (KL is a polymer by-product of the pulp and paper industry resulting from alkaline sulfide treatment of lignocellulose, and it has been widely used for lignin-related studies. Results Beta-proteobacterium Cupriavidus basilensis B-8 isolated from erosive bamboo slips displayed substantial KL degradation capability. With initial concentrations of 0.5–6 g L-1, at least 31.3% KL could be degraded in 7 days. The maximum degradation rate was 44.4% at the initial concentration of 2 g L-1. The optimum pH and temperature for KL degradation were 7.0 and 30°C, respectively. Manganese peroxidase (MnP and laccase (Lac demonstrated their greatest level of activity, 1685.3 U L-1 and 815.6 U L-1, at the third and fourth days, respectively. Many small molecule intermediates were formed during the process of KL degradation, as determined using GC-MS analysis. In order to perform metabolic reconstruction of lignin degradation in this bacterium, a draft genome sequence for C. basilensis B-8 was generated. Genomic analysis focused on the catabolic potential of this bacterium against several lignin-derived compounds. These analyses together with sequence comparisons predicted the existence of three major metabolic pathways: β-ketoadipate, phenol degradation, and gentisate pathways. Conclusion These results confirmed the capability of C. basilensis B-8 to promote KL degradation. Whole genomic sequencing and systematic analysis of the C. basilensis B-8 genome

  19. ELASTIC CHARACTERIZATION OF Eucalyptus citriodora WOOD

    Directory of Open Access Journals (Sweden)

    Adriano Wagner Ballarin

    2003-01-01

    Full Text Available This paper contributed to the elastic characterization of Eucalyptus citriodora grown inBrazil, considering an orthotropic model and evaluating its most important elastic constants.Considering this as a reference work to establish basic elastic ratios — several important elasticconstants of Brazilian woods were not determined yet - the experimental set-up utilized one tree of 65years old from plantations of “Horto Florestal Navarro de Andrade”, at Rio Claro-SP, Brazil. All theexperimental procedures attended NBR 7190/97 – Brazilian Code for wooden structures –withconventional tension and compression tests. Results showed statistical identity between compressionand tension modulus of elasticity. The relation observed between longitudinal and radial modulus ofelasticity was 10 (EL/ER ≈ 10 and same relation, considering shear modulus (modulus of rigidity was20 (EL/GLR ≈ 20. These results, associated with Poisson’s ratios herein determined, allow theoreticalmodeling of wood mechanical behavior in structures.

  20. [Population density of Eucalyptus urophylla plantation].

    Science.gov (United States)

    Huang, B; Lu, C

    2000-02-01

    This paper dealt with the relationships and correlation models of the population density of 5.6 years old Eucalyptus urophylla plantation with its crown width, diamter at breast height(DBH), tree height, individual standing volume, stand volume, wood properties and survital rate. The results showed that the population density remarkably affected DBH, individual standing volume, crown width, live branch height, stand volume and wood fiber width; but not affect tree height, basic density of wood, and length of wood fibers. It had a positive relationship with stand volume, live branch height and wood fibers width, and a negative relationship with DBH, individual standing volume and crown width. In addition, E. urophylla had a wide range of reasonable density. For short-rotation puplwoods, the optimum planting density of E. urophylla is 2000 individuals per hectare.

  1. Alcohol Dehydrogenation on Kraft Lignin-Derived Chars with Surface Basicity

    Directory of Open Access Journals (Sweden)

    Francisco J. García-Mateos

    2017-10-01

    Full Text Available The properties of lignin and its potential as a renewable source make it an ideal precursor for carbon products. Specifically, the high content of Na observed in Kraft lignin makes this industrial by-product an interesting precursor for the preparation of catalysts for different applications. In this work, basic activated carbons with different textural properties and surface chemistry were obtained from Kraft lignin by direct carbonization at various temperatures. The influence of a further washing treatment and partial gasification with CO2 was also evaluated. The carbon catalysts were tested as catalysts for the alcohol decomposition reaction. In this sense, 2-propanol, a molecule widely used for testing the acidic-basic character of heterogeneous catalysts, was selectively transformed into acetone, meanwhile, ethanol and methanol yielded mainly acetaldehyde and formaldehyde, respectively.

  2. Bio-based polyurethane prepared from Kraft lignin and modified castor oil

    OpenAIRE

    L. B. Tavares; C. V. Boas; G. R. Schleder; A. M. Nacas; D. S. Rosa; D. J. Santos

    2016-01-01

    Current challenges highlight the need for polymer research using renewable natural sources as a substitute for petroleum-based polymers. The use of polyols obtained from renewable sources combined with the reuse of industrial residues such as lignin is an important agent in this process. Different compositions of polyurethane-type materials were prepared by combining technical Kraft lignin (TKL) with castor oil (CO) or modified castor oil (MCO1 and MCO2) to increase their reactivity towards d...

  3. Alkali-treated kraft lignin as a component in flakeboard eesins

    Science.gov (United States)

    Mon-Lin. Kuo; Chung-Yun Hse; Dee-Hua Huang

    1991-01-01

    Southern pine kraft lignin was reacted with NaOH (15 and 20% based on dry lignin) at 170, 200, and 250°C for 30 and 60 min. Sweetgum flake boards bonded with phenolic resins containing 50% hydroxymethylated lignin prepared from some of the alkali treated lignins were compared with boards bonded with a neat PF resin. Results indicate that boards bonded with lignin-...

  4. Effet de l'hybridation interspecifique sur la teneur et la composition chimique des huiles essentielles d'eucalyptus cultivés au Maroc

    Directory of Open Access Journals (Sweden)

    Farah A.

    2002-01-01

    Full Text Available Interspecific hybridization effect on the content and the chemical composition of essential oils of eucalyptus grown in Morocco. In this work, the quality and quantity of the leave essential oils of five Eucalyptus hybrids were determined. The crosses of Eucalyptus globulus ssp. maideni, Eucalyptus globulus ssp. globulus, Eucalyptus grandis, Eucalyptus cladocalyx and Eucalyptus diversicolor with Eucalyptus camaldulensis have been studied. The average yield of parental species samples varies according to species. It is 3.4% for Eucalyptus globulus spp. maideni, 2.5% for Eucalyptus globulus spp. globulus and 1.6% for Eucalyptus diversicolor. Eucalyptus camaldulensis, Eucalyptus grandis and Eucalyptus cladocalyx are characterized by an average yield less than 1%, i.e. 0.8%, 0.4% and 0.3%, respectively. The average yields of the two hybrids Eucalyptus camaldulensis x Eucalyptus globulus spp. maideni and Eucalyptus camaldulensis x Eucalyptus diversicolor are 2.9% and 1.4% respectively. The combinations Eucalyptus camaldulensis x Eucalyptus globulus spp. globulus, Eucalyptus camaldulensis x Eucalyptus cladocalyx and Eucalyptus camaldulensis x Eucalyptus grandis are characterized by the lowest yields, i.e. 1%, 0.8% and 0.8% respectively. The analysis of the chemical composition shows that the hybrids Eucalyptus camaldulensis x Eucalyptus globulus spp. maideni give 1,8-cineole rates superior to 70%, which is required by the users. Comparatively to Eucalyptus camaldulensis, the essential oils of the other crosses reveal a slight decrease in percentage of this product. However, increases of the alpha-pinene and p-cymene contents have been recorded. In general, all products detected in essential oils have average percentages intermediate between those of parental species. Hybridization of eucalyptus can improve the quality and the quantity of eucalyptus essential oils.

  5. ESTABELECIMENTO IN VITRO DE CLONES HÍBRIDOS DE Eucalyptus globulus

    Directory of Open Access Journals (Sweden)

    Silvano Rodrigues Borges

    2012-01-01

    Full Text Available The present study aimed to evaluate the behavior of Eucalyptus grandis x Eucalyptus globulus and Eucalyptus urophylla x Eucalyptus globulus clones and the effect of different in vitro insertions (at 30, 90 and 150 days after pruning the donor plants in the in vitro establishment phase. The mini-stump plants, explant providers for the in vitro introductions, were cultivated under an indoor semi-hydroponic clonal mini-hedging. Nodal segment explants of 21 Eucalyptus urophylla x Eucalyptus globulus clones and eight Eucalyptus grandis x Eucalyptus globulus clones were harvested, disinfected and inoculated in an MS culture medium, supplemented with 0.5 mg L-1 of BAP and 0.1 mg L-1 of NAA. After 30 days in culture, evaluations were made and it was concluded that there were variations among the clones, as well as in vitro introductions, for the studied variables, where the in vitro establishment was possible for most clones.

  6. Perbaikkan Sifat Tanah Ultisol Untuk Meningkatkan Pertumbuhan Eucalyptus Urophylla Pada Ketinggian 0-400 Meter

    OpenAIRE

    Utomo, Budi

    2008-01-01

    132305100(4) Menurut Djapilus dan Suhaendi (1978) Eucalyptus termasuk dalam famili Myrtaceae, terdiri atas 500 jenis dan 138 varie¬tas. Pohon Eucalyptus pada umumnya mempunyai batang yang lurus, tinggi dan tidak banyak cabangnya.

  7. The energy efficiency partnership - Kraft General Foods and Boston Edison Company

    International Nuclear Information System (INIS)

    Crowley, J.C.; Donoghue, J.P.

    1993-01-01

    During the past twenty years, inordinate shifts in the supply and demand of energy have forced both electric utility companies and their customers to investigate new and innovative ways to satisfy the ever increasing demand for electricity. The Energy Efficiency Partnership, developed between Kraft General Foods and Boston Edison Company, presents an exemplary study of how two corporate giants creatively solved the problem of uncontrolled energy costs and its positive effect on the overall operations of Kraft General Foods, Framingham. But the Energy Efficiency Partnership did more than reduce energy costs, it provided benefits to all parties on the playing field. To understand its significance, a review of the partnership's history is paramount. The first official announcement of the Energy Efficiency Partnership was made on April 9, 1990. Framingham, MA, The Commonwealth of Massachusetts Kraft General Foods Framingham, and Boston Edison Company have joined forces in a $3.6 million dollar energy partnership that will help keep 250 industrial jobs in Massachusetts and could lead to the future expansion of the international food company's Framingham facility

  8. Energy evaluation of forest residues originated from Eucalyptus globulus Labill in Galicia

    Energy Technology Data Exchange (ETDEWEB)

    Nunez-Regueira, L.; Proupin-Castineiras, J.; Rodriquez-Anon, J.A. [University of Santiago (Spain). Dept. of Applied Physics

    2002-03-01

    The possibility of retrieving the energy contained in forest residues originating from wood exploitation in Galicia (Spain) is evaluated. This study was made on Eucalyptus globulus Labill occupying a forest surface of 240 000 ha. This species plays an important role in the economical development of Galicia, as it is the main forest species for production of pulp. Sampling was made over 1999 in seven different zones, three main stations plus four selected for comparison, situated in Galicia. The residues originating from cutting were sorted into three different groups and their calorific values were measured by static bomb calorimetry. These calorific values, close to 7200 kJ kg{sup -1}, make possible the use of this residual biomass as an energy source. Calorific values were measured by static bomb calorimeter in an oxygen atmosphere. Flammability was determined using a standard epiradiator. Simultaneously, some other parameters, elementary chemical composition, heavy metal contents, moisture, density, ash percentage after combustion in the bomb, and main bioclimatic characteristics, were also determined. (author)

  9. The Role of Eucalyptus Globulus Forest and Products in Carbon Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Arroja, L.; Dias, A.C.; Capela, I. [Environmental and Planning Department, University of Aveiro, 3810-193 Aveiro (Portugal)

    2006-01-15

    This study is a contribution to the ongoing debate about the selection of the approach for carbon accounting in wood products to be used, in the future, in the national greenhouse gas inventories under the UNFCCC (United Nations Framework Convention on Climate Change). Two accounting approaches are used in this analysis: the stock-change approach and the atmospheric-flow approach. They are applied to the Portuguese Eucalyptus globulus forest sector. To achieve this objective, the fluxes of wood removed from the forest are tracked through its life cycle, which includes products manufacture (mainly pulp and paper), use and final disposal (landfilling, incineration and composting). This study develops a framework to the estimation of carbon sequestration in the forest of E. globulus, a fast growing species, more specifically, in the calculation of the conversion factors such as bark and foliage percentages and densities, used to convert wood volumes into total biomass. A mass balance approach based on real data from mills is also proposed, in order to assess carbon emissions from wood processing. The results show that E. globulus forest sector was a carbon sink, but the magnitude of the carbon sequestration differs substantially depending on the accounting approach used. The contribution of the forest ecosystem was smaller than the aggregated contribution of wood products in use and in landfills (including industrial waste), which reinforces the role that wood products play in national carbon budgets.

  10. Kinetics of Eucalyptus globulus delignification in a methanol-water medium

    Energy Technology Data Exchange (ETDEWEB)

    Gilarranz, M.A.; Rodriguez, F.; Santos, A.; Oliet, M.; Garcia-Ochoa, F.; Tijero, J. [Univ. Complutense, Madrid (Spain). Dept. de Ingenieria Quimica

    1999-09-01

    The kinetics of Eucalyptus Globulus delignification in methanol-water pulping has been studied. A total of 17 isothermal runs at a liquor-to-wood ratio of 50 L/kg were carried out to develop the kinetic model describing the system. In a first series of experiments, eight models were considered to study the influence of temperature on the delignification rate. The most suitable model, which was discriminated according to statistical criteria, describes delignification as the consecutive dissolution of three lignin species: initial, bulk, and residual lignin, their content in wood being 10, 69, and 21%, respectively. Initial and residual delignification were considered as irreversible reactions and bulk delignification as reversible. The influence of hydrogen ion concentration was taken into account by means of a general power-law expression. The model proposed was taken into account by means of a general power-law expression. The model proposed was validated by reproducing the experimental data from four runs carried out under nonisothermal conditions and a liquor-to-wood ratio of 7 L/kg, which are closer to industrial operating conditions.

  11. The Role of Eucalyptus Globulus Forest and Products in Carbon Sequestration

    International Nuclear Information System (INIS)

    Arroja, L.; Dias, A.C.; Capela, I.

    2006-01-01

    This study is a contribution to the ongoing debate about the selection of the approach for carbon accounting in wood products to be used, in the future, in the national greenhouse gas inventories under the UNFCCC (United Nations Framework Convention on Climate Change). Two accounting approaches are used in this analysis: the stock-change approach and the atmospheric-flow approach. They are applied to the Portuguese Eucalyptus globulus forest sector. To achieve this objective, the fluxes of wood removed from the forest are tracked through its life cycle, which includes products manufacture (mainly pulp and paper), use and final disposal (landfilling, incineration and composting). This study develops a framework to the estimation of carbon sequestration in the forest of E. globulus, a fast growing species, more specifically, in the calculation of the conversion factors such as bark and foliage percentages and densities, used to convert wood volumes into total biomass. A mass balance approach based on real data from mills is also proposed, in order to assess carbon emissions from wood processing. The results show that E. globulus forest sector was a carbon sink, but the magnitude of the carbon sequestration differs substantially depending on the accounting approach used. The contribution of the forest ecosystem was smaller than the aggregated contribution of wood products in use and in landfills (including industrial waste), which reinforces the role that wood products play in national carbon budgets

  12. [Confusion and solution for vital pulp therapy].

    Science.gov (United States)

    Dingming, Huang; Qian, Lu; Qian, Liao; Ling, Ye; Xuedong, Zhou

    2017-06-01

    Dental pulp tissue plays a role in forming dentin, providing nutrition, conducting pain, and generating protective responses to environmental stimuli. Bacterial infection is the main cause of pulp disease, where histopathological changes are the histological basis for determining the choice of treatment and the evaluation of therapeutic effect. Thus, particular attention should be given to eliminate infection, as well as preserve and maintain pulpal health in teeth that show reversible or limited pulpal injuries. Vital pulp therapy, especially its indications and prognostic factors, has been a research hotspot that often causes confusion among clinicians. In this paper, we briefly introduce the confusion and solution for vital pulp therapy in terms of indications, pulp condition assessment, infection elimination, and capping material selection. In addition, we develop a clinical pathway and an operation normalization of vital pulp therapy to better perform the therapy.

  13. Potential of eleven Eucalyptus species for the production of essential oils

    OpenAIRE

    Silva,Paulo Henrique Müller da; Brito,José Otávio; Silva Junior,Francides Gomes da

    2006-01-01

    Most Eucalyptus plantations in Brazil aim the production of paper and charcoal, but the use of the species for lumbering, construction and extraction of essential oil has increased. Eleven species of Eucalyptus were assessed in regard to their essential oil production potential, nine never used before for commercial, essential oil extraction. Assessements were compared with Eucalyptus citriodora and Eucalyptus globulus, already explored in oil production for perfume and medical purposes, aimi...

  14. IBA AND MICROCUTTING COLLECTIONS IN THE MICROPROPAGATION OF Eucalyptus spp HYBRID CLONES.1

    OpenAIRE

    Gallo, Ricardo; Xavier, Aloisio; Moura, Luciana Coelho de; Oliveira, Brener de Almeida; Nascimento, Heloisa Rocha do; Otoni, Wagner Campos

    2017-01-01

    ABSTRACT This study aims to evaluate the effect of IBA concentrations and microcuttings successive collections in the micropropagation of Eucalyptus grandis x E. urophylla and Eucalyptus urophylla x E. globulus clones. Clumps containing six to eight buds of clones established in vitro were transferred to a 250 mL glass flask in JADS semisolid medium. Successive collections were performed every 20 days for Eucalyptus grandis x E. urophylla clone and every 30 days for Eucalyptus urophylla x E. ...

  15. Laccase modification of the physical properties of bark and pulp of loblolly pine and spruce pulp

    Science.gov (United States)

    William Kenealy; John Klungness; Mandla Tshabalala; Eric Horn; Masood Akhtar; Roland Gleisner; Gisela Buschle-Diller

    2004-01-01

    Pine bark, pine pulp, and spruce pulp were reacted with laccase in the presence of phenolic laccase substrates to modify the fiber surface properties. The acid-base and dispersive characteristics of these modified steam-treated thermomechanical loblolly pine pulps were determined by inverse gas chromatography. Different combinations of substrates with laccase modified...

  16. Assessing specific gravity of young Eucalyptus plantation trees using a resistance drilling technique

    Science.gov (United States)

    José Tarcísio da Silva Oliveira; Xiping Wang; Graziela Baptista Vidaurre

    2017-01-01

    The resistance drilling technique has been in focus for assessing the specific gravity (SG) of young Eucalyptus trees from plantations for pulpwood production. Namely, the data of 50 34-month-old and 50 62-monthold trees from Eucalyptus grandis × Eucalyptus urophylla clonal plantations was evaluated, while...

  17. Stem Cells of the Dental Pulp

    OpenAIRE

    Mahboobe Dehghani

    2014-01-01

     Dental Pulp Stem Cells (DPSCs) can be found within the cell rich zone of dental pulp. These stem cells, under specific stimuli, differentiate into many cell types which have wide therapeutic applications.   The dental stem cells are derived from both deciduous and permanent teeth. The viable dental stem cells are very simple to collect, without any mortality and morbidity. Dental pulp stem cells can be obtained from the patient’s vital pulp with the help of stem cell markers, which hel...

  18. The Determinants of Brazilian Pulp exports from 1980 to 2001

    OpenAIRE

    Bacha, Carlos José Caetano; SanJuan, Adriana E.

    2004-01-01

    This paper makes an econometric analysis of the determinants of BrazilÂ’s pulp exports. The time period from 1980 to 2001 is considered for estimating a supply equation of pulp exports. Exogenous variables considered were: price of Brazilian exported pulp, production cost of Brazilian pulp, productive capacity, exchange rate between dollar and domestic currency and lagged pulp exports. It was observed that BrazilÂ’s pulp exports have responded little to price fluctuation; however, these expor...

  19. Emission of volatile organic compounds from Portuguese eucalyptus forests

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, T.V.; Pio, C.A. [Universidade de Aveiro (Portugal). Dept. de Ambiente e Ordenamento

    2001-07-01

    Emission to the atmosphere of volatile organic compounds (VOCs) by Eucalyptus globulus was studied in the laboratory with young specimen, and in the field with adult trees. Eucalyptus emits both monoterpenes and isoprene. The leaves of young trees emit at higher rates than the leaves of adult trees. The emission of isoprene is highly predominant during the day. The emission of isoprene is dependent on temperature and solar radiation. The emission rate follows the Guenther algorithm if a based emission factor of 32 {mu}gg{sub dw} {sup -1}h{sup -1} is used, increasing with temperature, to a maximum at 40{sup o}C. At higher temperatures there is a decrease in the emission rate. The main C{sub 10} emitted is 1,8-cineol. Cineol emissions increase exponentially with temperature, and are also seasonally dependent. Application of the emission algorithm to the Portuguese eucalyptus forests shows that during summer isoprene and monoterpene emissions by eucalyptus are of the same order of anthropogenic VOC production. Furthermore, in certain regions, in the center-north of Portugal, where eucalyptus forests are predominant, isoprene emissions can reach an order of magnitude higher than anthropogenic production of VOCs during daytime periods in July and August. (Author)

  20. Pengaruh Pendidikan dan Pelatihan terhadap Kinerja Karyawan Bagian Produksi Pulp Making 8 PT. Indah Kiat Pulp And Paper Perawang

    OpenAIRE

    Etalia, Mikha; Andri, Seno

    2015-01-01

    This research aimed to determine the effect of education and training to employee performance in pulp production Pulp Making PT.Indah Kiat Pulp and Paper. Education and training as an independent variable (X) has been formulated by ability and skill instructors coach, the determination of material, facilities and infrastructure. While employee performance as the dependent variable (Y). This research was conducted on all employees pulp production Pulp Making PT.Indah Kiat Pulp and Paper by 40 ...