WorldWideScience

Sample records for chemical pulp

  1. EFFECT OF SCREW EXTRUSION PRETREATMENT ON PULPS FROM CHEMICAL PULPING

    Directory of Open Access Journals (Sweden)

    Cuihua Dong,

    2012-07-01

    Full Text Available The effect of compressive pretreatment before chemical pulping on the properties of poplar kraft and soda-AQ pulp was evaluated. Compressive pretreatment not only resulted in the dissolution of hemicellulose, but also leached extractives. Pulps made from compressive pretreated wood chips required lower beating energy than the untreated pulps to achieve the same beating degree of 45°SR, and the brightness of the handsheets was improved by 2% ISO. Compressive pretreatment allowed for efficient delignification and saved about 6% alkali consumption to achieve similar pulp screen yield. Furthermore, a higher content of fines and slightly lower mechanical properties were observed after the compressive treatment.

  2. Integrated chemical plants at the pulp mill

    Energy Technology Data Exchange (ETDEWEB)

    Ehtonen, P.; Hurme, M.; Jaervelaeinen, M.

    1995-12-31

    The goal of this paper is to present how the chemical plants can be integrated to the pulp mill. The integration renders possible to balance the chemical consumptions. The total mass balance of a pulp mill with the incoming fuel material and the outgoing waste and flue gases are discussed. The balance figures are presented for the chemicals of the modern fibre line, which will produce fully bleached softwood pulp with an improved effluent quality. The main benefits are lower chemical and transportation costs. The principal over-all plant process block diagrams and process descriptions are presented. The presented info system provides real time information on process and production status at overall mill and department levels. (author)

  3. SYNERGISTIC EFFECTS BETWEEN BIRCH CHEMICAL MECHANICAL PULPS AND ASPEN BLEACHED KRAFT PULP

    Institute of Scientific and Technical Information of China (English)

    Eric C. Xu; Yajun Zhou

    2004-01-01

    In this investigation, two different grades of birch chemical mechanical (P-RC APMP) pulps and aspen market bleached kraft pulp were compared by low consistency refining of the pulps separately and in different combinations. In addition, the separately refined pulps were also combined to compare with the pulps from the co-refined pulp blend. The results showed that in both cases there were synergistic effects between the two types of pulps: adding the birch P-RC APMP pulp to the aspen kraft pulp improved pulp properties, and the resultant pulp blends had a higher fiber bonding strength (tensile and tensile energy absorption) than the sum of weighted contributions from the individual components. Understanding this synergistic effect between chemical mechanical (P-RC APMP) and kraft pulps can help to improve their applications and performances in various papermaking processes.The results also showed that introducing, at least up to certain percentage of, the birch P-RC APMP pulp into the aspen bleached kraft pulp not only improves optical and bulk properties, but also maintains or improves tensile strength, even though the P-RC APMP pulp used has lower tensile than the kraft pulp.

  4. SYNERGISTIC EFFECTS BETWEEN BIRCH CHEMICAL MECHANICAL PULPS AND ASPEN BLEACHED KRAFT PULP

    Institute of Scientific and Technical Information of China (English)

    EricC.Xu; YajunZhou

    2004-01-01

    In this investigation, two different grades of birch chemical mechanical (P-RC APMP) pulps and aspen market bleached kraft pulp were compared by low consistency refining of the pulps separately and in different combinations. In addition, the separately refined pulps were also combined to compare with the pulps from the co-refined pulp blend. The results showed that in both cases there were synergistic effects between the two types of pulps: adding the birch P-RC APMP pulp to the aspen kraft pulp improved pulp properties, and the resultant pulp blends had a higher fiber bonding strength (tensile and tensile energy absorption) than the sum of weighted contributions from the individual components. Understanding this synergistic effect between chemical mechanical (P-RC APMP) and kraft pulps can help to improve their applications and performances in various papermaking processes. The results also showed that introducing, at least up to certain percentage of, the birch P-RC APMP pulp into the aspen bleached kraft pulp not only improves optical and bulk properties, but also maintains or improves tensile strength, even though the P-RC APMP pulp used has lower tensile than the kraft pulp.

  5. RECYCLING OF CHEMICAL PULP FROM WHEAT STRAW AND CORN STOVER

    OpenAIRE

    James Barsness; Ulrike Tschirner; Tamara Keeler

    2007-01-01

    Handsheets produced from corn stalks and wheat straw soda AQ pulps were recycled in the lab. Pulping of corn stalks resulted in a low pulp yield, low bonding strength, and low recyclability. Conversely, wheat straw fiber had a better yield, very good tensile properties, and showed a considerably better response to recycling. The tensile index of wheat straw fibers retained 67% of its original value after four cycles. It could be shown that recycling caused only small changes in chemical compo...

  6. Polyoxometalate catalyzed ozonation of chemical pulps in organic solvent media

    OpenAIRE

    Shatalov, Anatoly A.; Pereira, Helena

    2009-01-01

    Polyoxometalate (POM) catalyzed ozonation of chemical pulps in organic solvent media was found to be particularly effective and selective environmentally benign bleaching approach providing a way for substantial increase in pulp brightness, viscosity and degree of delignification in comparison with other ozone-based bleaching techniques. A series of tested low-boiling polar aprotic and protic organic solvents showed awell-defined capacity for ozonation improvement in the presence ...

  7. 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.

  8. Surface chemical and morphological properties of mechanical pulps, fibers and fines

    OpenAIRE

    Kangas, Heli

    2007-01-01

    The aim of this work was to study the surface chemical and morphological properties of different mechanical pulps with special focus on the effects of refining, bleaching and enzymatic modification on the surface properties of the isolated pulp fractions, namely fibers, fibrillar fines and flake-like fines. Special emphasis was placed on evaluating the suitability of time-of-flight secondary ion mass spectroscopy (ToF-SIMS) for studying the surface chemical properties of pulps and pulp fracti...

  9. Chemical characteristics and Kraft pulping of tension wood from Eucalyptus globulus labill

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    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.

  10. Different approaches to tailoring chemical pulp fibres

    OpenAIRE

    El-Sharkawy, Khalil

    2008-01-01

    The objective of this thesis work was to examine different approaches to tailor chemical fibres of different raw materials. The focus in searching for new approaches was on pressure screen fractionation, selective treatment of each fraction, mechanical pre-treatment before refining, refiner loadability and its link to fibre properties and filling design, and on-line quality control of fibre properties. The evaluation is based on the impacts on fibre properties, filtration, refining and the re...

  11. RECYCLING OF CHEMICAL PULP FROM WHEAT STRAW AND CORN STOVER

    Directory of Open Access Journals (Sweden)

    James Barsness

    2007-11-01

    Full Text Available Handsheets produced from corn stalks and wheat straw soda AQ pulps were recycled in the lab. Pulping of corn stalks resulted in a low pulp yield, low bonding strength, and low recyclability. Conversely, wheat straw fiber had a better yield, very good tensile properties, and showed a considerably better response to recycling. The tensile index of wheat straw fibers retained 67% of its original value after four cycles. It could be shown that recycling caused only small changes in chemical compo-sition, but that the crystallinity index increased considerably. To be able to understand the behavior of wheat straw fiber as part of a commercial papermaking furnish, a paper containing 20% wheat straw fiber was produced on a 24 inch pilot paper machine and was recycled using a handsheet mold with white water return. Chemical analysis of the control (no wheat fiber and the wheat-containing paper demonstrated slightly higher xylan content for the wheat-containing material. Recyclability increased slightly with addition of wheat fibers to a commercial furnish.

  12. 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.

  13. Evaluation of Inter-fiber Bonding in Wood Pulp Fibers by Chemical Force Microscopy

    OpenAIRE

    Dongbo Yan; Kecheng Li

    2012-01-01

    Atomic force microscopy with chemically modified tips was used to evaluate the inter fiber bonding properties of typical wood pulp fibers. Using –OH functionalized AFM tips as a model of cellulosic pulp fiber surfaces, pull-off forces and work of adhesion were measured in aqueous media. Three distinct tip-surface interactions were identified from force-displacement curves, representing three typical surface conditions of wet pulp fiber surfaces: solid, swollen and micro-fibrillated. The work...

  14. Effect of different locations on the morphological, chemical, pulping and papermaking properties of Trema orientalis (Nalita).

    Science.gov (United States)

    Jahan, M Sarwar; Chowdhury, Nasima; Ni, Yonghao

    2010-03-01

    The chemical compositions and fiber morphology of stem and branch samples from Trema orientalis at three different sites planted in Bangladesh were determined and their pulping, bleaching and the resulting pulp properties were investigated. A large difference between the stem and branch samples was observed. The stem samples have consistently higher alpha-cellulose and lower lignin content, and longer fibers than the branch samples in all sites. T. orientalis from the Dhaka and Rajbari region had higher alpha-cellulose content and longer fiber length, resulting in higher pulp yield and better papermaking properties. The T. orientalis pulp from Rajbari region also showed the best bleachability. PMID:19914825

  15. Effect of Pine-apple Pulp on Sensory and Chemical Properties of Burfi

    Directory of Open Access Journals (Sweden)

    Kapila Kamble

    Full Text Available Burfi is a popular khoa based confection and it’s contain considerable amount of milk solids. The manufacture of value added products by using seasonal fruit like pineapple. The present investigation shows that, the overall acceptability of the pineapple pulp Burfi prepared with 15 per cent pineapple pulp in treatment T4 (93.53 was highest and superior. Treatment T4 was more acceptable than all treatments in flavor, body texture and colour and appearance. The chemical composition of Burfi was affected due to addition of pineapple pulp to the fat, protein, total solids, moisture and ash. [Veterinary World 2010; 3(7.000: 329-331

  16. Analysing performance of bio-refinery systems by integrating black liquor gasification with chemical pulp mills

    OpenAIRE

    Naqvi, Muhammad Raza

    2012-01-01

    Mitigation of climate change and energy security are major driving forces for increased biomass utilization. The pulp and paper industry consumes a large proportion of the biomass worldwide including bark, wood residues, and black liquor. Due to the fact that modern mills have established infrastructure for handling and processing biomass, it is possible to lay foundation for future gasification based bio-refineries to poly-produce electricity, chemicals or bio-fuels together with pulp and pa...

  17. Detection of Chlorophenolic Compounds in Bleaching Effluents of Chemical Pulps

    Institute of Scientific and Technical Information of China (English)

    Chhaya Sharma; S.Mohanty; S.Kumar; N.J.Rao; li qian

    2008-01-01

    Laboratory bleaching effluents from the chlorination and caustic extraction stages of mixed wood kraft pulp processing have been analysed both qualitatively and quantitatively for various chlorophenolics by using GC.A number of chlorinated derivaties of phenols,catechols,guaiacols and syringaldehydes have been detected and their concentrations are estimated.The results are compared with that of different agriculture residue / hardwood pulps,which were reported in literature.The concentrations of various compounds detected have also been compared with their reported 96LC50 values.

  18. Biological treatments affect the chemical composition of coffee pulp

    NARCIS (Netherlands)

    Ulloa Rojas, J.B.; Verreth, J.A.J.; Amato, S.; Huisman, E.A.

    2003-01-01

    Biological treatments were applied to fresh coffee pulp (CoP) to improve its nutritive value for monogastric animals by reducing its content of cellulose and antinutritional factors (ANFs) such as total phenols, tannins and caffeine. Treatments were: (1) ensiling with 0, 50 and 100 g kg¿1 molasses f

  19. Biomass use in chemical and mechanical pulping with biomass-based energy supply

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, Jonas M.; Gustavsson, Leif [Department of Engineering Physics and Mathematics, Mid Sweden University, SE-831 25 Oestersund (Sweden)

    2007-12-15

    The pulp and paper industry is energy intensive and consumes large amounts of wood. Biomass is a limited resource and its efficient use is therefore important. In this study, the total amount of biomass used for pulp and for energy is estimated for the production of several woodfree (containing only chemical pulp) and mechanical (containing mechanical pulp) printing paper products, under Swedish conditions. Chemical pulp mills today are largely self-sufficient in energy while mechanical pulp mills depend on large amounts of external electricity. Technically, all energy used in pulp- and papermaking can be biomass based. Here, we assume that all energy used, including external electricity and motor fuels, is based on forest biomass. The whole cradle-to-gate chain is included in the analyses. The results indicate that the total amount of biomass required per tonne paper is slightly lower for woodfree than for mechanical paper. For the biomass use per paper area, the paper grammage is decisive. If the grammage can be lowered by increasing the proportion of mechanical pulp, this may lower the biomass use per paper area, despite the higher biomass use per unit mass in mechanical paper. In the production of woodfree paper, energy recovery from residues in the mill accounts for most of the biomass use, while external electricity production accounts for the largest part for mechanical paper. Motor fuel production accounts for 5-7% of the biomass use. The biomass contained in the final paper product is 21-42% of the total biomass use, indicating that waste paper recovery is important. The biomass use was found to be about 15-17% lower for modelled, modern mills compared with mills representative of today's average technology. (author)

  20. Influence of enzyme and chemical adsorption on the thermal degradation path for eucalyptus pulp

    International Nuclear Information System (INIS)

    Highlights: ► Enzymes and chemicals adsorption changes thermal degradation path of cellulose. ► Adsorptions on pulp fibres increase their amorphous cellulose content. ► Charring/volatilization ratio of pulp is affected by adsorptions. - Abstract: Changes in thermal degradation path of eucalyptus pulp support enzymes (laccase from Trametes villosa) and chemicals (Tris–HCl or tartrate–tartaric buffer) adsorption on cellulose during biobleaching, thereby increasing cellulose amount that degrades at low temperature and decreasing the apparent crystallinity (ApC) of cellulose crystallites. Changes in ApC, which can be assessed by thermogravimetric analysis —but not X-ray diffraction spectroscopy—affect cellulose volatilization; thus, the higher ApC is, the lower is char production and the higher the volatilization temperature. A linear relationship between ApC and the volatilization/charring ratio (V/C) was observed in this work.

  1. Influence of enzyme and chemical adsorption on the thermal degradation path for eucalyptus pulp

    Energy Technology Data Exchange (ETDEWEB)

    Barneto, Agustin G., E-mail: agustin.garcia@diq.uhu.es [Chemical Engineering Department, El Carmen Campus, University of Huelva, 21071 Huelva (Spain); Valls, Cristina [Textile and Paper Engineering Department, Universitat Politecnica de Catalunya, Colom 11, E-08222 Terrassa (Spain); Ariza, Jose [Chemical Engineering Department, El Carmen Campus, University of Huelva, 21071 Huelva (Spain); Roncero, M. Blanca [Textile and Paper Engineering Department, Universitat Politecnica de Catalunya, Colom 11, E-08222 Terrassa (Spain)

    2013-01-10

    Highlights: Black-Right-Pointing-Pointer Enzymes and chemicals adsorption changes thermal degradation path of cellulose. Black-Right-Pointing-Pointer Adsorptions on pulp fibres increase their amorphous cellulose content. Black-Right-Pointing-Pointer Charring/volatilization ratio of pulp is affected by adsorptions. - Abstract: Changes in thermal degradation path of eucalyptus pulp support enzymes (laccase from Trametes villosa) and chemicals (Tris-HCl or tartrate-tartaric buffer) adsorption on cellulose during biobleaching, thereby increasing cellulose amount that degrades at low temperature and decreasing the apparent crystallinity (ApC) of cellulose crystallites. Changes in ApC, which can be assessed by thermogravimetric analysis -but not X-ray diffraction spectroscopy-affect cellulose volatilization; thus, the higher ApC is, the lower is char production and the higher the volatilization temperature. A linear relationship between ApC and the volatilization/charring ratio (V/C) was observed in this work.

  2. THE PEROXYMONOCARBONATE ANIONS AS PULP BLEACHING AGENTS. PART 1. RESULTS WITH LIGNIN MODEL COMPOUNDS AND CHEMICAL PULPS

    Directory of Open Access Journals (Sweden)

    Francis K Attiogbe

    2010-08-01

    Full Text Available The peroxymonocarbonate mono-anion (HCO4─ is generated when the bicarbonate anion is added to a H2O2 solution. The mono-anion is believed to have a pKa value of ca. 10 and as such would start dissociating to the di-anion (CO42─ at pH ca. 8. The mono-anion should demonstrate electrophilic properties, while the di-anion should be a nucleophile. In an alkaline, non-sulfur pulping process such as soda/AQ, Na2CO3 could be obtained from the chemical recovery system and carbonated with CO2 from a flue gas stream to produce NaHCO3. In such a case only H2O2 would need to be purchased to generate the peroxymonocarbonate (PMC anions. Bicarbonate anions could also be produced from the carbonation of solutions containing NaOH, Mg(OH2 or mined Na2CO3. One or both of the PMC anions was found to be effective in oxidizing two lignin model compounds as well as lowering the lignin content of kraft and soda/AQ hardwood pulps. The PMC anions were generated in-situ by NaHCO3 or Na2CO3 + CO2 addition to dilute H2O2 solutions.

  3. Cassava Peels for Alternative Fibre in Pulp and Paper Industry: Chemical Properties and Morphology Characterization

    OpenAIRE

    Ashuvila Mohd Aripin; Angzzas Sari Mohd Kassim; Zawawi Daud; Mohd Zainuri Mohd Hatta

    2013-01-01

    Without a proper waste management, the organic wastes such as cassava peels could result in increased amount of solid waste dump into landfill. This study aims to use non-wood organic wastes as pulp for paper making industries; promoting the concept of ‘from waste to wealth and recyclable material’. The objective  of this study is to determine the potential of casssava peel as alternative fibre in pulp and paper based on its chemical properties and surface morphology characteristic. Quantifie...

  4. PHYSICAL, CHEMICAL, AND LIPID COMPOSITION OF JUÇARA (EUTERPE EDULIS MART.) PULP

    OpenAIRE

    Paula Porrelli Moreira da SILVA; Leandro Francisco do CARMO; Guilherme Mei SILVA; Mayra Fernanda SILVEIRA-DINIZ; Casemiro, Renata Cristina; Spoto, Marta Helena Fillet

    2013-01-01

    Juçara palm (Euterpe edulis Martius) is native to the Brazilian Atlantic Forest and is an endangered species due to intensive exploration to produce hearts of palm. In the last few years, juçara plantation has been implemented for fruit production and pulp extraction, similar to açaí (Euterpe oleracea Mart.). The objective of this study was to assess the physical, chemical, and lipid composition of juçara pulp, in order to establish the exact measures of its quality ai...

  5. Penentuan Chemical Oxygen Demand (Cod) Limbah Cair Pulp Dengan Metode Spektrofotometri Visible Di PT. Toba Pulp Lestari, Tbk

    OpenAIRE

    Rona Monica Sihaloho

    2009-01-01

    Penentuan Kebutuhan Oksigen Kimia (KOK) limbah cair pulp pada PT. Toba Pulp Lestari telah dilakukan dengan metode spektrofotometri sinar tampak. Pengukuran dilakukan pada panjang gelombang 600 nm untuk sampel dari Inlet Primary Clarifier dan Outlet Primary Clarifier dan pada panjang gelombang 520 nm untuk sampel dari Outlet Secondary Clarifier. Hasil KOK yang diperoleh dari limbah cair pulp pada Inlet Primary Clarifier 500,2 mg/liter; Outlet Primary Clarifier 439,1 mg/liter; dan Outlet S...

  6. Chemical and sensory characteristics of pulp and peel 'cajá-manga' (Spondias cytherea Sonn. jelly

    Directory of Open Access Journals (Sweden)

    Ellen Silva Lago-Vanzela

    2011-06-01

    Full Text Available Cajá-manga (Spondias cytherea is a fruit with intense aroma and a sweet sour taste, thus being very appreciated. Its peel, in spite of being more fibrous, is tender and many times consumed with the pulp. The peel is a part of foods normally discarded, but many times, it is rich in taste and fibers, representing an option at the elaboration of new foods. Since there are no reports in the literature on the use of cajá-manga peel for jelly making, this work had the purpose of developing and evaluating this product. Based on the results, it was noted that the peels presented higher contents of protein, lipids, ashes, food fiber, total carbohydrates and pectin, and lower content of moisture, when compared to the pulp. The peel and the pulp (control jellies presented the following physical-chemical characteristics: moisture, 29.5 and 34.2%; proteins, 0.19 and 0.27%; lipids, 0.11 and 0.16%; total sugars, 56.5 and 65.5%; and total soluble solids, 69 and 66 ºBrix, respectively. The sensory analysis indicated that the product elaborated from the peel presented satisfactory acceptance for all the assessed attributes: appearance, color, odor, texture, taste and global evaluation. It is concluded that the total substitution of the pulp by the peel in the formulation, results in a product with good nutritional value with no sensory damages.

  7. Steam system opportunity assessment for the pulp and paper, chemical manufacturing, and petroleum refining industries: Main report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2002-10-01

    This report assesses steam generation and use in the pulp and paper, chemical, and petroleum refining industries, and estimates the potential for energy savings from implementation of steam system performance and efficiency improvements.

  8. Effect of the chemical cycle on the energy use when producing sulfate pulp

    Energy Technology Data Exchange (ETDEWEB)

    Maripuu, M.

    1982-09-01

    The influence of the chemical cycle on the energy conservation of a sulfate pulp factory has been investigated. The problem concerning ballast (non-load running) is crucial. The operational problems of causticizing and lime reburning have been looked into. Energy use could be reduced by a closer control of ballast, which is difficult to calculate. Heavy losses are found to take place when plant operetions are interfered with.

  9. Effect of surface properties of fibres on some paper properties of mechanical and chemical pulp

    OpenAIRE

    Koljonen, Krista

    2004-01-01

    The overall goal of the thesis was to find correlations between the surface precipitates of pulps and selected strength properties of paper sheets. Special attention was paid to the surface lignin and extractives of fibres. The main surface-characterising techniques employed were electron spectroscopy for chemical analysis (ESCA), atomic force microscopy (AFM) and the polyelectrolyte titration method. In addition, a Wilhelmy balance for single fibres, time-of-flight secondary ion mass spectro...

  10. STORAGE OF CHEMICALLY PRETREATED WHEAT STRAW – A MEANS TO ENSURE QUALITY RAW MATERIAL FOR PULP PREPARATION

    Directory of Open Access Journals (Sweden)

    Terttu Heikkilä

    2010-07-01

    Full Text Available The aim of this study was to evaluate effects of chemical pretreatment and storage on non-wood pulping and on pulp quality. The processes studied were hot water treatment followed by alkaline peroxide bleaching or soda cooking. The results showed that it is possible to store wheat straw outside for at least one year without significant changes in the raw material chemical composition and without adverse effects on the resulting pulp quality. The results are significant to the industry using non-woods to ensure the availability and the quality of the raw-material throughout the year in spite of the short harvesting time.

  11. Analysing performance of bio-refinery systems by integrating black liquor gasification with chemical pulp mills

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, Muhammad R.

    2012-07-01

    Mitigation of climate change and energy security are major driving forces for increased biomass utilization. The pulp and paper industry consumes a large proportion of the biomass worldwide including bark, wood residues, and black liquor. Due to the fact that modern mills have established infrastructure for handling and processing biomass, it is possible to lay foundation for future gasification based bio-refineries to poly-produce electricity, chemicals or bio-fuels together with pulp and paper products. There is a potential to export electricity or bio-fuels by improving energy systems of existing chemical pulp mills by integrating gasification technology. The present study investigates bio-fuel alternatives from the dry black liquor gasification (BLG) system with direct causticization and direct methane production from the catalytic hydrothermal gasification (CHG) system. The studied systems are compared with bio-fuel alternatives from the Chemrec BLG system and the improvements in the energy systems of the pulp mill are analyzed. The results are used to identify the efficient route based on system performance indicators e.g. material and energy balances to compare BLG systems and the conventional recovery boiler system, potential biofuel production together with biomass to biofuel conversion efficiency, energy ratios, potential CO{sub 2} mitigation combining on-site CO{sub 2} reduction using CO{sub 2} capture and potential CO{sub 2} offsets from biofuel use, and potential motor fuel replacement. The results showed that the dry BLG system for synthetic natural gas (SNG) production offers better integration opportunities with the chemical pulp mill in terms of overall material and energy balances. The biofuel production and conversion efficiency are higher in the CHG system than other studied configurations but at a cost of larger biomass import. The dry BLG system for SNG production achieved high biomass to biofuel efficiency and considerable biofuel production

  12. [Chemical characteristics of the pulp and oil of the annona tree (Annona coriaceae)].

    Science.gov (United States)

    Agostini, T da S; Cecchi, H M; Barrera-Arellano, D

    1995-09-01

    Belonging to the Annonaceae family, marolo (Annona coriaceae) is a native species of the Brazilian "cerrado" región (Minas Gerais, Goiás and Distrito Federal) and can be found in South American tropical zones. Its fruits are highly consumed by local people and commercialized in markets or street stalls. There is, however, a tendency for the extinction of marolo due to deforestation and the large scale plantation of monocultures instead of native plants. The literature still offers no data on the chemical composition of the proximate composition and vitamin C, A and tannin contents were carried out on the yellow marolo pulp as well as the determination of the physico-chemical characteristics of the seed oil. Five batches of fruit from the Alfenas region--south of Minas Gerais State--were analysed in this work and their average composition were: humidity 77%, total sugar 15%, reducing sugar 11%, crude protein 1%, lipids 3%, fiber 5% and fixed mineral residue 1%. The contents of vitamin C and A were 8.2 mg/100g and 117.5 RE/100g, respectively, and the tannin content was 245 mg/100g. The results showed high fiber and lipid contents of marolo pulp in comparison with many other tropical fruit pulps. The vitamin C contents were equivalent to those found in avocado, pineapple and watermelon, while the vitamin A contents were equivalent to papaya, peach, guava and several other tropical fruits. Marolo seed contains 45% of oil on a dry basis. Its composition and physico-chemical characteristics showed the possibility of producing a good quality oil, with great potential for the fine oil market. However the presence of alkaloids in the oil needs to be further studied. Their elimination could be done by refining or extraction in a continuous press. The results exalt the high quality of marolo pulp, showing that the preservation of native species should be stimulated. PMID:9382684

  13. Cassava Peels for Alternative Fibre in Pulp and Paper Industry: Chemical Properties and Morphology Characterization

    Directory of Open Access Journals (Sweden)

    Ashuvila Mohd Aripin

    2013-11-01

    Full Text Available Without a proper waste management, the organic wastes such as cassava peels could result in increased amount of solid waste dump into landfill. This study aims to use non-wood organic wastes as pulp for paper making industries; promoting the concept of ‘from waste to wealth and recyclable material’. The objective  of this study is to determine the potential of casssava peel as alternative fibre in pulp and paper based on its chemical properties and surface morphology characteristic. Quantified parameters involved are holocellulose, cellulose, hemicellulose, lignin, one percent of sodium hydroxide, hot water solubility and ash content. The chemical characterization was in accordance with relevant TAPPI Test, Kurscher-Hoffner and Chlorite methods. Scanning electron microscopy (SEM was used to observe and determine the morphological characteristic of untreated cassava peels fibre. In order to propose the suitability of the studied plant as an alternative fibre resource in pulp and paper making, the obtained results are compared to other published literatures especially from wood sources. Results indicated that the amount of holocellulose contents in cassava peels (66% is the lowest than of wood (70 - 80.5% and canola straw (77.5%; however this value is still within the limit suitability to produce paper. The lignin content (7.52% is the lowest than those of all wood species (19.9-26.22%. Finally, the SEM images showed that untreated cassava peel contains abundance fibre such as hemicellulose and cellulose that is hold by the lignin in it. In conclusion, chemical properties and morphological characteristics of cassava peel indicated that it is suitable to be used as an alternative fibre sources for pulp and paper making industry, especially in countries with limited wood resources

  14. SUGARCANE BAGASSE PULPING AND BLEACHING: THERMAL AND CHEMICAL CHARACTERIZATION

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Fernandes Pereira

    2011-05-01

    Full Text Available Cellulose fibers were isolated from sugarcane bagasse in three stages. Initially sugarcane bagasse was subjected to a pre-treatment process with hydrolyzed acid to eliminate hemicellulose. Whole cellulosic fibers thus obtained were then subjected to a two-stage delignification process and finally to a bleaching process. The chemical structure of the resulting cellulose fibers was studied by Fourier Transform Infrared (FTIR spectroscopy. Scanning Electron Microscopy (SEM and X-ray diffraction (XRD were used to analyze the effects of hydrolysis, delignification, and bleaching on the structure of the fibers. Two different thermal analysis techniques were used to study the bleaching cellulose fibers. These techniques confirmed that cellulose fibers were isolated from sugarcane bagasse. A future goal is to use these fibers as reinforcement elements in composites, organic-inorganic hybrid, and membranes for nanofiltration.

  15. Impact of lignin and carbohydrate chemical structures on degradation reactions during hardwood kraft pulping processes

    Directory of Open Access Journals (Sweden)

    Ricardo B. Santos

    2013-02-01

    Full Text Available Most studies aimed at determining rates of hardwood delignification and carbohydrate degradation have focused on understanding the behavior of a single wood species. Such studies tend to determine either the delignification rate or the rate of carbohydrate degradation without examining the potential interactions resulting from related variables. The current study provides a comprehensive evaluation on both lignin and carbohydrate degradation during kraft pulping of multiple hardwood species. The kraft delignification rates of E. urograndis, E. nitens, E. globulus, sweet gum, maple, red oak, red alder, cottonwood, and acacia were obtained. Furthermore, the kinetics of glucan, xylan, and total carbohydrate dissolution during the bulk phase of the kraft pulping process for the above species were also investigated. The wide ranges of delignification and carbohydrate degradation rates were correlated to wood chemical characteristics. It appears that the S/G ratio and lignin-carbohydrate-complexes (LCCs are the main characteristics responsible for the differences in kraft pulping performance among the hardwoods studied.

  16. PHYSICAL, CHEMICAL, AND LIPID COMPOSITION OF JUÇARA (EUTERPE EDULIS MART. PULP

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    Paula Porrelli Moreira da SILVA

    2013-01-01

    Full Text Available Juçara palm (Euterpe edulis Martius is native to the Brazilian Atlantic Forest and is an endangered species due to intensive exploration to produce hearts of palm. In the last few years, juçara plantation has been implemented for fruit production and pulp extraction, similar to açaí (Euterpe oleracea Mart.. The objective of this study was to assess the physical, chemical, and lipid composition of juçara pulp, in order to establish the exact measures of its quality aiming to demonstrate the product potential for commercialization. Our results revealed high content of essential minerals, such as magnesium, copper, zinc, iron, and manganese, antioxidant compounds (anthocyanins, and high quality fatty acids (palmitic, oleic and linoleic, indicating the importance and functionality of the product for human consumption. Due to the high content of dark pigments found in juçara pulp, this product can also be used as a natural food dye, not only producing an attractive appearance, but also adding beneficial compounds for human health.

  17. Alkaline peroxide pulping of oil palm empty fruit bunch by variation of chemical strength

    Science.gov (United States)

    Dermawan, Yunita Megasari; Ghazali, Arniza; Daud, Wan Rosli Wan; Lazin, Mohd Azli Khairil Mat

    2012-09-01

    Papers produced from oil palm empty fruit bunches (EFB) via Alkaline Peroxide Pulping (APP) was preceded by three main steps; dewaxing of EFB, alkaline peroxide (AP) impregnation into EFB and refining of biomass to generate pulp. The experiment was carried by varying chemical level and number of impregnation stages. For 2:2.5% AP level, two-stage impregnation improved hand sheets tear index by 45%, 164% boost in tensile index, 26% enhancement in zero span index and more than 5% in burst index. By applying 8:10% AP level, significant improvements were gained at the third and fourth stages of AP impregnation. Although there was no significant change in hand sheet strength with multiple impregnation for 4:5% AP level, improvement in brightness of hand sheets was apparent, analogous to the effect of increasing AP level. The found paper properties development show that alkaline peroxide pulping of EFB could be adapted to various targeted properties by adjustment of AP level and impregnation stages.

  18. CHEMICAL COMPOSITION, CRYSTALLINITY, AND THERMAL DEGRADATION OF BLEACHED AND UNBLEACHED KENAF BAST (Hibiscus cannabinus PULP AND NANOFIBERS

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    Mehdi Jonoobi

    2009-05-01

    Full Text Available Kenaf (Hibiscus cannabinus nanofibers were isolated from unbleached and bleached pulp by a combination of chemical and mechanical treatments. The chemical methods were based on NaOH-AQ (anthraquinone and three-stage bleaching (DEpD processes, whereas the mechanical techniques involved refining, cryo-crushing, and high-pressure homogenization. The size and morphology of the obtained fibers were characterized by environmental scanning electron microscopy (ESEM and transmission electron microscopy (TEM, and the studies showed that the isolated nanofibers from unbleached and bleached pulp had diameters between 10-90 nm, while their length was in the micrometer range. Fourier transform infrared (FTIR spectroscopy demonstrated that the content of lignin and hemicellulose decreased in the pulping process and that lignin was almost completely removed during bleaching. Moreover, thermogravimetric analysis (TGA indicated that both pulp types as well as the nanofibers displayed a superior thermal stability as compared to the raw kenaf. Finally, X-ray analyses showed that the chemo-mechanical treatments altered the crystallinity of the pulp and the nanofibers: the bleached pulp had a higher crystallinity than its unbleached counterpart, and the bleached nanofibers presented the highest crystallinity of all the investigated materials.

  19. Research of cementation of pulps having a complex physicochemical composition and stored in tanks of mining chemical combine

    International Nuclear Information System (INIS)

    As a result of previous activities at the Radiochemical plant of the Mining and Chemical Combine (MCC), several thousands of cubic meters of radioactive hydroxide pulps with complex physicochemical compositions have been accumulated in the MCC storage tanks. The report represents the main results of research on cementation technology to be planned for use at Mining Chemical Combine for immobilization of hydroxide pulps. A wide range of experiments using hydroxide-pulp simulators have been performed. These experiments were meant to develop optimal parameters for the cementation process to ensure obtaining the required-quality cement compound. The results of the research on pulp simulators and real waste have made it possible to draw the following conclusions. First, when using Portland cements with the sorption additive for pulp solidification, the obtained cement compounds meet the regulatory requirements as regards their mechanical strength, water stability and frost resistance. Secondly, the application potential has been demonstrated for a pulse type mixer for the purpose of pulp solidification. (A.C.)

  20. Refining of Polysulfide Pulps

    Science.gov (United States)

    Copur, Yalcin

    This study compares the modified kraft process, polysulfide pulping, one of the methods to obtain higher pulp yield, with conventional kraft method. More specifically, the study focuses on the refining effects of polysulfide pulp, which is an area with limited literature. Physical, mechanical and chemical properties of kraft and polysulfide pulps (4% elemental sulfur addition to cooking digester) cooked under the same conditions were studied as regards to their behavior under various PFI refining (0, 3000, 6000, 9000 revs.). Polysulfide (PS) pulping, compared to the kraft method, resulted in higher pulp yield and higher pulp kappa number. Polysulfide also gave pulp having higher tensile and burst index. However, the strength of polysulfide pulp, tear index at a constant tensile index, was found to be 15% lower as compared to the kraft pulp. Refining studies showed that moisture holding ability of chemical pulps mostly depends on the chemical nature of the pulp. Refining effects such as fibrillation and fine content did not have a significant effect on the hygroscopic behavior of chemical pulp.

  1. KRAFT PULPING CHARACTERISTICS OF THREE MOROCCAN EUCALYPTI. PART 1. PHYSICAL AND CHEMICAL PROPERTIES OF WOODS AND PULPS

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    Mohammed El Moussaouiti,

    2012-02-01

    Full Text Available Two eucalyptus hybrids (EGC 39, EGC 241, resulting from crosses between Eucalyptus grandis and Eucalyptus camaldulensis, were investigated to see if they could produce kraft papermaking fibers with low lignin and adequate physical properties. The two hybrids were harvested at an age of 8 years along with 6-8 year old Eucalyptus camaldulensis (Rostrata. All three eucalypti were grown in the area of Gharb in the North-West of Morocco. The tracheids in the two hybrids had a very high Runkel ratio (2 x cell wall thickness/lumen diameter and produced kraft paper sheets with low tensile strength due to a low degree of fiber collapse thus a low relative bonded area. These fibers could be used to increase the stiffness of a papermaking furnish. The lignin in the EGC 39 chips was more reactive in kraft pulping as compared to the other two eucalypti. Methoxyl analyses and nitrobenzene oxidation (NBO of the in-situ lignin (wood meals were performed, and it was concluded that the syringyl content of the EGC 39 lignin was less than or equal to those in the other two eucalypti. Differences in the guaiacyl fraction of the three samples will be discussed in Part 2 of this series.

  2. Green chemicals from pulp production black liquor by partial wet oxidation.

    Science.gov (United States)

    Muddassar, Hassan Raja; Melin, Kristian; de Villalba Kokkonen, Daniela; Riera, Gerard Viader; Golam, Sarwar; Koskinen, Jukka

    2015-11-01

    To reduce greenhouse gas emissions, more sustainable sources of energy, fuel and chemicals are needed. Biomass side streams such as black liquor, which is a by-product of pulp production, has the potential to be used for this purpose. The aim of the study was the production of carboxylic acids, such as lactic acid, formic acid and acetic acid, from kraft and non-wood black liquor. The processes studied were partial wet oxidation (PWO) and catalytic partial wet oxidation (CPWO). The results show that the yield of carboxylic acid is higher when treated by PWO than the results from CPWO at temperatures of 170 °C and 230 °C. The results shows that the PWO process can increase the yield of carboxylic acids and hydroxy acids in black liquor, reduce lignin content and decrease pH, which makes further separation of the acids more favourable. The hydroxy acids are valuable raw materials for biopolymers, and acetic acid and formic acid are commonly used chemicals conventionally produced from fossil feedstock. PMID:26377325

  3. CHEMICAL CHARACTERIZATION OF PULP COMPONENTS IN UNBLEACHED SOFTWOOD KRAFT FIBERS RECYCLED WITH THE ASSISTANCE OF A LACCASE/HBT SYSTEM

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    Luiz Pereira Ramos

    2007-11-01

    Full Text Available Oxidative treatments, without and with assistance of a Laccase-Mediator System (LMS, were characterized in relation to their effects on the chemical composition and strength properties of the fibrous fraction of an unbleached recycled softwood kraft pulp. The LMS, composed of a Trametes hirsuta laccase extract and 1-hydroxybenzotriazole (HBT, was applied on the fibrous fraction of a recycled pulp at low consistency under continuous stirring and oxygen bubbling. Control treatments adding neither the enzyme nor the mediator were also considered. The LMS treatment caused a partial reversion of the detrimental effects of hornification. A considerable increase in the amount of carbonyl groups on the lignin structure was observed as a result of the enzyme treatment. The amount of extractives in ethanol:toluene also increased after the enzymatic treatment, and the dioxane-soluble kraft lignin underwent a noticeable decrease in its apparent molecular mass. This latter effect was readily attributed to the hydrolysis of aryl-ether bonds that survived the severity employed in the pulping process. These observations were useful to explain why LMS-recycled fibers produce handsheets with 9.4% better tensile strength than the control pulps.

  4. Increased delignification rate of Dendrocalamus strictus (Roxburgh nees by Schizophyllum commune Fr.; Fr. to reduce chemical consumption during pulping process

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    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.

  5. Thermal Processing Alters the Chemical Quality and Sensory Characteristics of Sweetsop (Annona squamosa L.) and Soursop (Annona muricata L.) Pulp and Nectar.

    Science.gov (United States)

    Baskaran, Revathy; Ravi, Ramasamy; Rajarathnam, Somasundaram

    2016-01-01

    The objective of this study was to investigate the effect of thermal processing on the chemical quality and sensory characteristics of Annona squamosa L. and Annona muricata L. fruit pulps and nectar. The fruit pulps were pasteurized at 85 °C for 20 min and nectar prepared as per Food Safety and Standards Authority of India (FSSAI) specifications. The chemical composition of fresh and heated pulps of A. squamosa and A. muricata showed that compared to fresh, the chemical profile and sensory profile changed in heated samples and nectar. The free and bound phenolics of A. squamosa increased in heated pulp (127.61 to 217.22 mg/100 g and 150.34 to 239.74 mg/100 g, respectively), while in A. muricata, free phenolics increased very marginally from 31.73 to 33.74 mg/100 g and bound phenolics decreased from 111.11 to 86.91 mg/100 g. This increase in phenolic content may be attributed to the perception of bitterness and astringency in A. squamosa pulp on heating. In electronic tongue studies, principal component analysis (PCA) confirmed that the fresh and heated pulps had different scores, as indicated by sensory analysis using qualitative descriptive analysis (QDA). E-tongue analysis of samples discriminated the volatile compounds released from the heated A. squamosa and A. muricata fruit pulps and nectar in their respective PCA plots by forming different clusters. PMID:26642109

  6. Physical and chemical characterization of the pulp of different varieties of avocado targeting oil extraction potential

    OpenAIRE

    Edinéia Dotti Mooz; Natália Moreno Gaiano; Marilis Yoshie Hayashi Shimano; Rodrigo Dantas Amancio; Marta Helena Fillet Spoto

    2012-01-01

    The aim of this study was to evaluate the physicochemical properties of avocado pulp of four different varieties (Avocado, Guatemala, Dickinson, and Butter pear) and to identify which has the greatest potential for oil extraction. Fresh avocado pulp was characterized by moisture, protein, fat, ash, carbohydrates and energy contents were determined. The carotenoids and chlorophyll contents were determined by the organic solvent extraction method. The results showed significant differences in t...

  7. Fate of nitrogen in the chemical recovery cycle of a kraft pulp mill

    Energy Technology Data Exchange (ETDEWEB)

    Kymaelaeinen, M. [Aabo Akademi, Turku (Finland). Process Chemistry Group

    2001-07-01

    The kraft pulping process is the dominant chemical method for producing wood pulp. In the process, about half the mass of the wood is dissolved, separated from the wood fibers and transferred to the chemical recovery cycle. Nitrogen in the wood mostly dissolves and goes on to the recovery cycle. This reactive nitrogen is the source of NO{sub x} emissions in the recovery boiler. Little information has been available regarding the nitrogen elsewhere in the recovery cycle. Ammonia (NH{sub 3}) emissions have been observed at many mills, especially around the causticizing area, but the causes of the emissions have not been understood. Furthermore, the smelt exiting the boiler has been found to contain a significant part of the black liquor nitrogen. This finding, and the general lack of knowledge regarding nitrogen flow and behavior in the other parts of the recovery cycle, were the incentives for this work. The main routes of the reactive nitrogen, including the main formation and release points for NH{sub 3} in the recovery cycle, were clarified at two operating pulp mills. The key reaction and rates for NH{sub 3} formation under process conditions were determined. In addition, the formation of the ammonia precursor - the smelt nitrogen - was studied under black liquor combustion conditions. Further, NO formation in black liquor combustion was investigated by the single droplet experimental technique. The results provide an overall understanding of the behavior of nitrogen in the recovery cycle. The smelt nitrogen exiting the recovery boiler was equal to about one third of the black liquor nitrogen introduced to the boiler. The smelt nitrogen was found gradually to convert to ammonia in the liquor cycle during the subsequent green and white liquor processing. From the experimental kinetic studies, the key reaction for ammonia formation was identified as the hydrolysis of cyanate (OCN{sup -}) under alkaline conditions. All the smelt nitrogen was finally removed from

  8. Cellular biopolymers and molecular structure of a secondary pulp and paper mill sludge verified by spectroscopy and chemical extraction techniques.

    Science.gov (United States)

    Edalatmanesh, Maryam; Sain, Mohini; Liss, Steven N

    2010-01-01

    For proper treatment, recycling, or disposal of the pulp and paper mill secondary sludge qualitative and quantitative determination of its characteristics are necessary. Chemical extraction, quantitative characterization, and spectroscopic experiments have been performed to determine the molecular composition and chemical functionality of a pulp and paper mill secondary sludge. In order to extract the low-molecular-weight substances, soxhlet extraction with polar and non-polar solvents was performed where most of the target substances (17±1.3%.) were extracted after 2 hours. Over time, this extraction followed a first-order kinetics. Fiber analyses have shown 12±3% lignin, 28±3% cellulose, and 12±4% hemicelluloses content. The ash content was about 17±0.5%. In this work, 7 and 16% intra- and extracellular polymeric substances, respectively, were extracted from the secondary sludge. EPS and mixture of intra- and extracellular biopolymers have shown similar chemical functionalities. These analyses confirmed that the paper secondary sludge consisted mainly of wood fiber, i.e. lignocellulosic substances, along with proteins and polysaccharides originated from microorganisms. PMID:21123914

  9. ECF BLEACHING WITH A FINAL HYDROGEN PEROXIDE STAGE: IMPACT ON THE CHEMICAL COMPOSITION OF Eucalyptus globulus KRAFT PULPS

    Directory of Open Access Journals (Sweden)

    Pedro E. G. Loureiro

    2010-11-01

    Full Text Available Two industrial elemental chlorine free (ECF bleaching sequences, D0(EOPD1(EPD2 and OQ(PODP, are compared with respect to the bulk content of lignin, carboxyl, hexeneuronic acids (HexA, and reducing groups after each bleaching stage. HexA groups contribute significantly to the total content of carboxyl groups, and their degradation during chlorine dioxide bleaching is reflected by a decrease of the carboxyl content. The higher degradation using an enhanced use of oxygen-based bleaching chemicals is associated with a higher fiber charge reduction, mainly due to xylan depletion. Additionally, the effect of process variables of a laboratory final hydrogen peroxide stage on the chemical composition of the fully bleached pulp (D0(EOPD1P and OQ(PODP is studied. The ability of final peroxide bleaching to raise the content of carboxyl groups is dependent on the operating conditions and pulp bleaching history. A balance between carbohydrate oxidation and dissolution of oxidized groups determines the effect on fiber charge. The effect of hydrogen peroxide stabilizers added into the final stage on the content of carboxyl groups is also reported.

  10. Physical and chemical characterization of the pulp of different varieties of avocado targeting oil extraction potential

    Directory of Open Access Journals (Sweden)

    Edinéia Dotti Mooz

    2012-06-01

    Full Text Available The aim of this study was to evaluate the physicochemical properties of avocado pulp of four different varieties (Avocado, Guatemala, Dickinson, and Butter pear and to identify which has the greatest potential for oil extraction. Fresh avocado pulp was characterized by moisture, protein, fat, ash, carbohydrates and energy contents were determined. The carotenoids and chlorophyll contents were determined by the organic solvent extraction method. The results showed significant differences in the composition of the fruit when varieties are compared. However, the striking feature in all varieties is high lipid content; Avocado and Dickinson are the most suitable varieties for oil extraction, taking into account moisture content and the levels of lipids in the pulp. Moreover, it could be said that the variety Dickinson is the most affected by the parameters evaluated in terms of overall quality. Chlorophyll and carotenoids, fat-soluble pigments, showed a negative correlation with respect to lipids since it could be related to its function in the fruit. The varieties Avocado and Dickinson are an alternative to oil extraction having great commercial potential to be exploited thus avoiding waste and increasing farmers’ income.

  11. Isolation and chemical identification of lipid derivatives from avocado (Persea americana) pulp with antiplatelet and antithrombotic activities.

    Science.gov (United States)

    Rodriguez-Sanchez, Dariana Graciela; Flores-García, Mirthala; Silva-Platas, Christian; Rizzo, Sheryl; Torre-Amione, Guillermo; De la Peña-Diaz, Aurora; Hernández-Brenes, Carmen; García-Rivas, Gerardo

    2015-01-01

    Platelets play a pivotal role in physiological hemostasis. However, in coronary arteries damaged by atherosclerosis, enhanced platelet aggregation, with subsequent thrombus formation, is a precipitating factor in acute ischemic events. Avocado pulp (Persea americana) is a good source of bioactive compounds, and its inclusion in the diet as a source of fatty acid has been related to reduced platelet aggregability. Nevertheless, constituents of avocado pulp with antiplatelet activity remain unknown. The present study aims to characterize the chemical nature of avocado constituents with inhibitory effects on platelet aggregation. Centrifugal partition chromatography (CPC) was used as a fractionation and purification tool, guided by an in vitro adenosine diphosphate (ADP), arachidonic acid or collagen-platelet aggregation assay. Antiplatelet activity was initially linked to seven acetogenins that were further purified, and their dose-dependent effects in the presence of various agonists were contrasted. This process led to the identification of Persenone-C (3) as the most potent antiplatelet acetogenin (IC₅₀=3.4 mM) among the evaluated compounds. In vivo evaluations with Persenone A (4) demonstrated potential protective effects against arterial thrombosis (25 mg kg⁻¹ of body weight), as coagulation times increased (2-fold with respect to the vehicle) and thrombus formation was attenuated (71% versus vehicle). From these results, avocado may be referred to as a functional food containing acetogenin compounds that inhibit platelet aggregation with a potential preventive effect on thrombus formation, such as those that occur in ischaemic diseases. PMID:25319210

  12. Chemical and sensory characteristics of pulp and peel 'cajá-manga' (Spondias cytherea Sonn.) jelly

    OpenAIRE

    Ellen Silva Lago-Vanzela; Priscila Ramin; Marcelo Andrés Umsza-Guez; Ginaldo Vieira Santos; Eleni Gomes; Roberto da Silva

    2011-01-01

    Cajá-manga (Spondias cytherea) is a fruit with intense aroma and a sweet sour taste, thus being very appreciated. Its peel, in spite of being more fibrous, is tender and many times consumed with the pulp. The peel is a part of foods normally discarded, but many times, it is rich in taste and fibers, representing an option at the elaboration of new foods. Since there are no reports in the literature on the use of cajá-manga peel for jelly making, this work had the purpose of developing and eva...

  13. Chemical composition and pulping of date palm rachis and Posidonia oceanica--a comparison with other wood and non-wood fibre sources.

    Science.gov (United States)

    Khiari, R; Mhenni, M F; Belgacem, M N; Mauret, E

    2010-01-01

    In the present paper, the valorisation of two residues: Posidonia oceanica and date palm rachis was investigated. First, their chemical composition was studied and showed that they present amounts of holocellulose, lignin and cellulose similar to those encountered in softwood and hardwood. Extractives in different solvents and ash contents are relatively high. Moreover, ash composition assessment showed that silicon is the major component (17.7%) for P. oceanica. The high ash quantity and the low DP (about 370) may be considered as serious disadvantages of P. oceanica, in the pulping and papermaking context. Oppositely, the properties of rachis date palm and those of the ensuing pulp, obtained from a classical soda-anthraquinone cooking, demonstrated the suitability of this agricultural by-product for papermaking. Preliminary tests conducted on unrefined pulp suspensions and handsheets from date palm rachis in terms of freeness, Water Retention Value and mechanical properties allowed confirming the good quality of date palm rachis fibres. PMID:19766481

  14. THE EFFECT OF CHARGE AND CHEMICAL STRUCTURE OF CATIONIC SURFACTANTS ON LASER TONER AGGLOMERATION UNDER ALKALINE PULPING CONDITIONS

    Directory of Open Access Journals (Sweden)

    Jie Jiang,

    2012-02-01

    Full Text Available Laboratory-scale agglomeration experiments followed by image analysis were used to evaluate the effectiveness of different cationic surfactants on the 1-octadecanol agglomeration of a negatively charged laser toner. Various types of surfactants with different geometric structures were investigated. It was found that this toner became agglomerated under neutral pulping conditions, but it did not agglomerate under alkaline conditions at all. A small amount of the cationic surfactant compensated for the agglomeration disruption caused by the negative surface charge of the toner and made this toner agglomerate very well. These cationic surfactants consist of a chemical structure of C12 to C18 saturated alkyl hydrophobic chains. The positive charge of these surfactants played the major role in alleviating agglomeration disruption. Additionally, an extra phenol group on these surfactants contributed only minor advantages for toner agglomeration in the presence of 1-octadecanol. The best co-agglomeration performance occurred within a very narrow range of similar total positive charge densities based on the total toner weight. It was also found that this positive charge effect could not be applied to the chemical compounds of high molecular weight polymeric materials.

  15. Efficiency of Chemical Treatments on Reduction of COD and Turbidity of Deinked Pulp Waste Water

    Directory of Open Access Journals (Sweden)

    Shademan Pourmousa

    2013-12-01

    Full Text Available The effect of poly aluminum chloride with cationic or anionic polymers in treatment of deinked waste water has been studied. The experiments were carried out in jar tests with poly aluminum chloride dosages range of 5-20 mg/l, cationic or anionic polymers dosages range of 1-3 mg/l, pH range of 7.2-8.2, rapid mixing at 100rpm for 2minute, followed by slow mixing at 40 rpm for 10minute and settling for 20minute. The effectiveness of poly aluminum chloride with cationic or anionic polymers were measured based on reduction of turbidity and chemical oxygen demand. The combination of poly aluminum chloride with cationic or anionic polymers is found to give the increase efficiency of purification in the treatment of the deinked waste waters.it can achieve almost66.82 % of turbidity and 63.04 %ofchemical oxygen demand reduction at an optimum dosage of 15mg/l poly aluminum chloride with 3mg/l cationic polymers andpH of 8.2.Theresult suggests that the waste water purified can be used for internal process applications but for injection it to environments goals can be passed biological treatments.

  16. 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. PMID:20335025

  17. Effect of temperature-controlled fermentation on physico-chemical properties and lactic acid bacterial count of durian (Durio zibethinus Murr.) pulp.

    Science.gov (United States)

    Wasnin, Ramdiah M; Karim, Muhammad Shahrim Abdul; Ghazali, Hasanah Mohd

    2014-11-01

    Effects of controlled-temperature fermentation on several physico-chemical properties, lactic acid bacteria (LAB) counts and aroma of durian pulp were examined by storing fresh durian pulp was mixed with 2 % (w/w) salt and stored at 15 °C, 27 °C and 40 °C for 10 days. Storage at 15 °C did not affect the properties of the pulp much. However, at 27 °C and 40 °C, pH and total soluble solids decreased up to 60 % and 52 %, respectively, with greater losses at 27 °C. Titratable acidity, which increased at 27 °C, was due to lactic and acetic acids formation. Loss of sucrose and increases in glucose were greater at 27 °C. LAB population increased up to Day 3 of storage, and then decreased slightly. Principal component analysis based on aroma examination using a zNose(TM) showed better retention of aroma profile at 27 °C. Overall, durian fermented at 27 °C was more acceptable than the one prepared at 40 °C, and it is ready to be consumed between Day 4 and 6. PMID:26396291

  18. Comparison Study of Manometric Respirometric Test and Common Chemical Methods in the Determination of BOD bold7 in a Pulp and Paper Mill's Wastewaters

    OpenAIRE

    Risto Pöykiö; Hanna Prokkola; Toivo Kuokkanen; Jaakko Rämö; Hannu Nurmesniemi; Katri Roppola

    2006-01-01

    The biological oxygen demand (BOD) test is widely used in many wastewater treatment plants. The conventional BOD tests are usually time-consuming and the results are often out of date for process control purposes. The aim of this research was to compare the manometric respirometric test with common chemical methods in the determination of BOD of wastewater from a pulp and paper mills as well as to evaluate the BOD7 values of both wastewaters from the short-term respirometric measurements. Th...

  19. 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.

  20. 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. PMID:15935655

  1. Pollution prevention for the kraft pulp and paper industry

    Energy Technology Data Exchange (ETDEWEB)

    1992-09-01

    The document is an annotated bibliography of publications related to pollution prevention in the Kraft segment of the pulp and paper industry. It is organized by process area as follows: chip preparation, chemical pulping, pulp washing, bleaching, chemical recovery, recausticizing, power generation, wastewater treatment, papermaking, and general plant. The document contains 269 citations.

  2. Chemical and rheological properties of a starch-rich fraction from the pulp of the fruit cupuassu (Theobroma grandiflorum)

    Energy Technology Data Exchange (ETDEWEB)

    Vriesmann, Lucia C.; Silveira, Joana L.M. [Universidade Federal do Parana, Departamento de Bioquimica e Biologia Molecular, CP 19046, CEP 81531-990, Curitiba-PR (Brazil); Petkowicz, Carmen L. de O [Universidade Federal do Parana, Departamento de Bioquimica e Biologia Molecular, CP 19046, CEP 81531-990, Curitiba-PR (Brazil)], E-mail: clop@ufpr.br

    2009-03-01

    The pulp obtained from the fruit of cupuassu (Theobroma grandiflorum) was extracted with hot aqueous 0.1% citric acid to give fraction 0.1CA-2 in 15% yield. This was the predominant component polysaccharide, 91% of which was composed of starch, by an iodine test and monosaccharide composition, and its {sup 13}C NMR spectrum was consistent with that of a high amylose starch. The content of amylose found in fraction 0.1CA-2 was 71%. This value is higher than those of common starches of cereal grains, tubers, roots, and other fruits. The fraction was submitted to rheological examination, gels being prepared on heating with concentrations of 4 to 7% (w/w). A non-Newtonian behavior was observed, and gel viscosity and strength depended on the concentration. The presence of starch, as well as the presence of previously investigated pectin, conferred the high viscosity and gelling capability of the pulp.

  3. Chemical and rheological properties of a starch-rich fraction from the pulp of the fruit cupuassu (Theobroma grandiflorum)

    International Nuclear Information System (INIS)

    The pulp obtained from the fruit of cupuassu (Theobroma grandiflorum) was extracted with hot aqueous 0.1% citric acid to give fraction 0.1CA-2 in 15% yield. This was the predominant component polysaccharide, 91% of which was composed of starch, by an iodine test and monosaccharide composition, and its 13C NMR spectrum was consistent with that of a high amylose starch. The content of amylose found in fraction 0.1CA-2 was 71%. This value is higher than those of common starches of cereal grains, tubers, roots, and other fruits. The fraction was submitted to rheological examination, gels being prepared on heating with concentrations of 4 to 7% (w/w). A non-Newtonian behavior was observed, and gel viscosity and strength depended on the concentration. The presence of starch, as well as the presence of previously investigated pectin, conferred the high viscosity and gelling capability of the pulp

  4. Effect of sucrose and pectin addition on physical, chemical, thermal and rheological properties of frozen/thawed pineapple pulps

    Science.gov (United States)

    Conceição, Márcia Cavalcante; Fernandes, Tatiana Nunes; Prado, Mônica Elisabeth Torres; de Resende, Jaime Vilela

    2012-09-01

    Pectin (0-1.0 g/100 mL) and sucrose (0-20 g/100 mL) were added to pineapple pulp to improve their rheological properties, thermal properties and stability after freezing and thawing processes. The properties of the mixes were characterized before and after freezing and thawing. Samples were frozen at -20°C, and the freeze concentration was evaluated every 60 min. The thawing rate was evaluated at 19°C and quantified by photographic editing and image analysis software. The thawing rates and values for the freeze concentration were leveled out at pectin concentrations above 0.5 g/100 mL pectin, which indicated that pectin functions to maintain structural homogeneity during freezing. In the thawed samples, the plastic viscosity values were leveled out from pectin concentrations (0.25-0.75 g/100 mL) as the sucrose concentration increased when compared to unfrozen samples. The differences between the rheological parameters of the unfrozen and frozen/thawed pulps, the higher yield stress values after thawing were attributed to the size of suspended particles in the pulp. Applications can specify formulations of frozen products containing pectin, where these properties can be handled after thawing the product.

  5. 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.

  6. Canola straw chemimechanical pulping for pulp and paper production.

    Science.gov (United States)

    Hosseinpour, Reza; Fatehi, Pedram; Latibari, Ahmad Jahan; Ni, Yonghao; Javad Sepiddehdam, S

    2010-06-01

    Non-wood is one of the most important raw materials for pulp and paper production in several countries due to its abundance and cost-effectiveness. However, the pulping and papermaking characteristics of canola straw have rarely been investigated. The objective of this work was to determine the potential application of canola straw in the chemimechanical pulping (CMP) process. At first, the chemical composition and characteristics of canola straw were assessed and compared with those of other non-woods. Then, the CMP pulping of canola straw was conducted using different dosages of sodium sulfite and sodium hydroxide. The results showed that, by applying a mild chemical pretreatment, i.e., 4-12% (wt.) NaOH and 8-12% (wt.) Na(2)SO(3), in the CMP pulping of canola straw, the pulp brightness reached almost 40%ISO, and the strength properties were comparable to those of bagasse CMP and of wheat straw CMP. The impact of post-refining on the properties of canola straw CMP was also discussed in this work. PMID:20144862

  7. 稻草生化制浆新技术的实验室研究及中试生产%The laboratory research and pilot production of the new technology of bio-chemical pulping from rice straw

    Institute of Scientific and Technical Information of China (English)

    钱鹭生

    2001-01-01

    The paper introduces the results of the laboratory research and pilot production of the new technology of bio-chemical pulping from rice straw. The research results and pilot production show that the bio-chemical pulps treated with No.38 engineering bacterium enzyme has approximately the same physical and mechanical property as that of quality broad-leaved wood pulp,and the its pulping effluent is much lower than that of straw pulp from the traditional alkali method,thus the environmental protection measures are in some degree realized.%本文报导了我国稻草生化制浆新技术的研究及中试投产成果。研究成果及中试显提提要:示了用No.38工程菌酶处理的生化浆,其物理机械性能达到与优质阔叶木浆相媲美提提要:的程度,制浆排水的负载亦比常规碱法草浆低得多,排水污染防治措施有所落实。

  8. Papermaking fibers from giant reed (Arundo donax L. by advanced ecologically friendly pulping and bleaching technologies

    Directory of Open Access Journals (Sweden)

    Pereira, H.

    2006-07-01

    Full Text Available The anatomical structure and chemical composition of the stem-wall material of giant reed is considered from the viewpoint of raw material characterization for industrial fiber production. The effect of stem morphology (nodes and internodes on pulping results and general pulp properties is discussed. The advantages of application of modern organic solvent based (organosolv pulping technologies to giant reed are shown in comparison with the conventional (kraft method. The conditions optimization for Ethanol-Alkali pulping (a selected organosolv pulping process is given, and the chemical kinetics of the principal macromolecular components during ethanol-alkali pulping is described. The bleachability of organosolv pulps by short totally chlorine free (TCF bleaching sequences using hydrogen peroxide and ozone as the active bleaching chemicals without pulp pre-delignification is examined and compared with kraft pulps. The enzymatic pre-treatment of reed organosolv pulps by commercial xylanase preparation is considered as a possibility toward the improvement of pulp bleachability.

  9. HIGH CONSISTENCY PULPING OF OLD NEWSPRINT AND ITS FLOTATION PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    Chunhui Zhang; Menghua Qin

    2004-01-01

    The mechanical and chemical effect on the pulping properties of the old newsprint was studied using a FORMAX Micro-Maelstrom Laboratory Pulper, and the flotation conditions such as velocity of air flow,air pressure and flotation time were also discussed with a FORMAX Deink Cell. The results show that sodium hydroxide, sodium silicate, hydrogen peroxide and deinking agent are the key factors in the chemical effect, and pulping consistency is more important than pulping time and rotation speed in the mechanical effect during the high consistency pulping of the ONP. In general, the chemical effect has a greater influence on the deinked pulp properties than the mechanical effect.

  10. Japanese Journal of Paper Technology. `98 Technology Annual (machinery, equipment, engineering, maintenance, laboratory utilities, chemical); Kami pulp gikyo times. 1998 nendo gijutsu manual (kikai shizai yakuhin soran)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-08-11

    The general survey of the 1998 technology manual on machinery/materials/chemicals was made public. In the part of machinery/materials, the following are included: pulp manufacturing machine/equipment, used paper treatment/stuff preparation machine/equipment, dedusting/cleaning/concentrating equipment, stuff pump/chemicals pump, paper machine and related equipment, paper machine related tools/machinery/materials, finishing machine/handling equipment, processing facility/processing finishing facilities, equipment for secondary processing/paper product making, measuring control/test analysis equipment/facility, utility/environment related equipment/facility, safety equipment/other related equipment/machinery/materials, etc. In the part of chemicals, assistants for cooking/decoloration/used paper treatment, sizing agent, paper strength reinforcing/paper quality improving agents, filler/pigment, dye/color pigment, inorganic/synthetic fiber, work improving agent, antiseptics/antifungal agent, felt cleaner, antiforming agent, freeness/yield improving agents, flocculant, various assistants, utility use chemicals, functionalizer, processing agent, coating/laminate/chemicals for paper product making, etc. 630 figs, 76 tabs.

  11. PRODUCTION OF DISSOLVING GRADE PULP FROM ALFA

    Directory of Open Access Journals (Sweden)

    Baya Bouiri

    2010-02-01

    Full Text Available Alfa, also known as Stipa tenacissimaI or “halfa”, is grown in North Africa and south Spain. Due to its short fiber length, paper made from alfa pulp retains bulk and takes block letters well. In this study alfa was evaluated for bleached pulp production. Two cellulose pulps with different chemical compositions were pulped by a conventional kraft process. One sample was taken from the original alfa material and another from alfa that had been pretreated by diluted acid. The pulp produced from the pretreated alfa was bleached by the elemental-chlorine-free sequences DEPD and DEDP. The yield, Kappa number, brightness, and α- cellulose content of bleached and unbleached pulps were evaluated. The results showed that during the chemical pulping process, treated alfa cooked more easily than the original alfa. The treated alfa pulp also showed very good bleaching, reaching a brightness level of 94.8% ISO with a yield of 93.6% at an α-cellulose content 96.8(% with a DEDP bleaching sequence, compared to 83.2% ISO brightness level, 92.8% yield, and 95.1% α-cellulose content for bleached pulp with a DEPD bleaching sequence. Therefore, this alfa material could be considered as a worthwhile choice for cellulosic fiber supply.

  12. Eucalyptus kraft pulp production: Thermogravimetry monitoring

    International Nuclear Information System (INIS)

    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.

  13. Changes in Biochemical and Physico-chemical Qualities during Drying of Pulp Preconditioned and Fermented Cocoa (Theobroma cacao Beans

    Directory of Open Access Journals (Sweden)

    Emmanuel Ohene Afoakwa

    2014-04-01

    Full Text Available This study investigated the effects of post-harvest pod storage as a means of pulp preconditioning on the souring production, flavour precursors development and free fatty acids during drying of fermented Ghanaian cocoa beans. A 4 x 4 full factorial experiment was conducted with pod storage (0, 7, 14, 21 days and drying times (0, 2, 4 and 6 days as the principal factors. The souring/acidification indices (pH and titratable acidity, total sugar, total nitrogen and free fatty acids (FFA were studied using standard analytical methods. The results showed that titratable acidity, total sugars and total nitrogen in cocoa beans decreased during drying and with increasing pod storage durations probably due to their participation in Maillard non-enzymatic reactions to form flavour volatiles and colour pigments as Amadori intermediates. By contrast, FFAs and pH increased during drying and with increasing pod storage durations. Pod storage for up to 7 days followed by 6 days of fermentation and drying respectively produced beans with acceptable FFA values below 1.75% whilst enhancing the flavour precursors development and reductions in nib acidity. However, these observed changes were more dependent on pod storage than on drying.

  14. Biorefinery pulp mill - BiSe

    Energy Technology Data Exchange (ETDEWEB)

    Mielonen, K. [Lappeenranta University of Technology (Finland)], email: katriina.mielonen@lut.fi

    2012-07-01

    A need to utilize woody material in a more efficient way to produce pulp, biofuels and energy was seen as a key factor in the development of new pulp mill biorefineries. There are many alternatives to execute the biorefinery concept. In the Biorefinery Pulp Mill-project approached prehydrolysis of wood chips and acid hydrolysis of logging residue for the production of bioethanol, as well as the separation of lignin for the production of biodiesel were studied. The main goal of the project was to examine these new biofuel production methods and processes for the improvement of the competitiveness, energy effectiveness and economic profitability of domestic pulp mills, while keeping in mind the main product, chemical pulp.

  15. Selective fractionation of Sugar Beet Pulp for release of fermentation and chemical feedstocks; optimisation of thermo-chemical pre-treatment.

    Science.gov (United States)

    Hamley-Bennett, C; Lye, G J; Leak, D J

    2016-06-01

    The effect of time and pressure on the selective extraction of sugar beet pectin using steam pre-treatment on unprocessed Sugar Beet Pulp was evaluated using a design of experiments approach. This process gave the highest solubilisation of pectin oligomers at a relatively low pressure and longer time (5Bar, 24min), whilst leaving the majority of the cellulose fraction intact. This method of steam pre-treatment fits into the concept of a sugar beet biorefinery as it valorises an existing waste stream without requiring any further physical processing such as milling or dilution with water. The residual cellulose fraction was enriched in cellulose and could be effectively fermented into ethanol by yeast after enzymatic digestion, producing 0.48g ethanol per gram of glucose. PMID:26978325

  16. Chemical Composition and Antioxidative Properties of Seeds of Moringa oleifera and Pulps of Parkia biglobosa and Adansonia digitata Commonly used in Food Fortification in Burkina Faso

    Directory of Open Access Journals (Sweden)

    W.R. Compaoré

    2011-01-01

    Full Text Available This study aimed to identify the nutrient composition and antioxidant properties of seeds of Moringa oleifera and pulps of Adansonia digitata and Parkia biglobosa. Crude proteins, carbohydrates, lipids, crude fibers, ashes and mineral elements were determined. Total phenols, flavonoids, proanthocyanidins of seeds and pulps were reported. The seeds of Moringa oleifera are particularly rich in proteins (35.37±0.07 g/100 g, lipids (43.56±0.03 g/100 g, and minerals (Mg2+ and Zn2+. Pulps of Adansonia digitata and Parkia biglobosa have a relatively high carbohydrates content (67.8±0.05 g/100 g and 67.66±0.05 g/100 g, respectively. Glucose, fructose and sucrose were the main carbohydrates of seeds of Moringa oleifera and pulps of Adansonia digitata and Parkia biglobosa. Seeds of Moringa oleifera have the highest proanthocyanidin and flavonoid content whereas pulps of Adansonia digitata and Parkia biglobosa were characterized by the highest total phenol content. Seeds of Moringa oleifera had the strongest MBTH radicals scavenging activity (99.74% compared to the pulps of Adansonia digitata and Parkia biglobosa 94.98 and 79.40%, respectively. This study indicated that these pulps and seeds have a good potential in macro and micronutrients content and for its valorization they can be effectively used to fortify staple food particularly for children and contribute to eradicate malnutrition due to micronutrients deficiencies.

  17. Chemical Composition and Antioxidative Properties of Seeds of Moringa oleifera and Pulps of Parkia biglobosa and Adansonia digitata Commonly used in Food Fortification in Burkina Faso

    OpenAIRE

    W.R. Compaoré; P.A. Nikièma; H.I.N. Bassolé; A. Savadogo; J. Mouecoucou; D.J. Hounhouigan and S.A. Traoré

    2011-01-01

    This study aimed to identify the nutrient composition and antioxidant properties of seeds of Moringa oleifera and pulps of Adansonia digitata and Parkia biglobosa. Crude proteins, carbohydrates, lipids, crude fibers, ashes and mineral elements were determined. Total phenols, flavonoids, proanthocyanidins of seeds and pulps were reported. The seeds of Moringa oleifera are particularly rich in proteins (35.37±0.07 g/100 g), lipids (43.56±0.03 g/100 g), and minerals (Mg2+ and Zn2+). Pulps of Ada...

  18. Injuries to Scots pine mycorrhizas and chemical gradients in forest soil in the environment of a pulp mill in Central Finland

    International Nuclear Information System (INIS)

    The occurrence and condition of Scots pine mycorrhizas were studied at different distances from a pulp mill in Central Finland. The chemical analyses of the soil humus layer in the vicinity of the mill revealed increased levels of ammonium-nitrogen, sulphur and calcium but unaltered concentrations of phosphorus and magnesium. Higher nitrate levels and nitrification were clearly detected at some sites which had recently been limed. Significant decreases in root ramification index and number of living mycorrhizas were found in a 0-0.6 km zone surrounding the factory but these parameters increased with increasing distance. Within a 2 km zone around the mill there were abundant Cenococcum geophilus and Paxilus involutus-type mycorrhizas while lowered frequencies of several other mycorrhizal types were detected. An ultrastructural study revealed changes in several types of mycorrhizas, the clearest of which were increased tannin deposition in cortical cells, intracellular growth of hyphae in cortical cells and the appearance of electron dense accumulations in the vacuoles of the funal cells. The ultrastructural changes observed were distributed at least to a distance of 3 km from the mill and occurred in the roots of trees that had only a slight loss of needle mass. Nitrogen deposition is suspected to be the primary cause of root decline but atmospheric SO2 through the tree crown is also likely to be a contributing factor. 37 refs., 10 figs., 7 tabs

  19. Caracterização química do "pitch" em indústria de celulose e papel de Eucalyptus Chemical characterization of pitch in Eucalyptus pulp and paper industry

    Directory of Open Access Journals (Sweden)

    Mariluze P. Cruz

    2006-06-01

    Full Text Available The chemical analysis of the acetone, chloroform, toluene and methanol extracts of a pitch sample was carried out by IR and GC-MS, leading to the identification of sixty nine compounds, including fatty acids, alcohols and hydrocarbons. Analysis of the acetone extractive of a eucalyptus wood used in Brazil for pulp production was also carried out, resulting in identification of fifty nine compounds, including mainly fatty acids, phenolic compounds, beta-sitosterol and other steroids. This analysis showed that pitch formation had a contribution from wood extractives and other sources of contamination. The results obtained and the methodology applied can be used by the pulp industry to develop new methods of pitch control.

  20. High-yield pulping effluent treatment technologies

    International Nuclear Information System (INIS)

    The objective of this report is to examine the high-yield (mechanical) pulp processes with respect to environmental issues affected by the discharge of their waste streams. Various statistics are given that support the view that high-yield pulping processes will have major growth in the US regions where pulp mills are located, and sites for projects in the development phase are indicated. Conventional and innovative effluent-treatment technologies applicable to these processes are reviewed. The different types of mechanical pulping or high-yield processes are explained, and the chemical additives are discussed. The important relationship between pulp yield and measure of BOD in the effluent is graphically presented. Effluent contaminants are identified, along with other important characteristics of the streams. Current and proposed environmental limitations specifically related to mechanical pulp production are reviewed. Conventional and innovative effluent-treatment technologies are discussed, along with their principle applications, uses, advantages, and disadvantages. Sludge management and disposal techniques become an intimate part of the treatment of waste streams. The conclusion is made that conventional technologies can successfully treat effluent streams under current waste-water discharge limitations, but these systems may not be adequate when stricter standards are imposed. At present, the most important issue in the treatment of pulp-mill waste is the management and disposal of the resultant sludge

  1. INTERACTIONS BETWEEN CATIONIC POLYELECTROLYTE AND PULP FINES

    Directory of Open Access Journals (Sweden)

    Elina Orblin

    2011-05-01

    Full Text Available Papermaking pulps are a mixture of fibres, fibre fragments, and small cells (parenchyma or ray cells, usually called pulp fines. The interactions between pulp fines and a cationic copolymer of acrylamide and acryloxyethyltrimethyl ammonium chloride were investigated based on solid-liquid isotherms prepared under different turbulence, and subsequent advanced surface characterization using X-ray photoelectron spectroscopy (XPS and time-of-flight secondary ion mass spectrometry (ToF-SIMS. The surface charge and surface area of pulp fine substrates were measured by methylene blue sorption-XPS analysis and nitrogen adsorption combined with mercury porosimetry, respectively. The driving force behind polyelectrolyte adsorption was the amount of the surface anionic charge, whereas surface area appeared to be of less importance. Based on a comparison of solid-liquid and XPS sorption isotherms, different polyelectrolyte conformations were suggested, depending on the types of fines: A flatter conformation and partial cell-wall penetration of polyelectrolytes on kraft fines from freshly prepared pulp, and a more free conformation with extended loops and tails on lignocellulosic fines from recycled pulp. Additionally, ToF-SIMS imaging proved that recycled pulp fines contained residual de-inking chemicals (primarily palmitic acid salts that possibly hinder the electrostatic interactions with polyelectrolytes.

  2. REPLACEMENT OF SOFTWOOD KRAFT PULP WITH ECF-BLEACHED BAMBOO KRAFT PULP IN FINE PAPER

    Directory of Open Access Journals (Sweden)

    Guanglei Zhao

    2010-06-01

    Full Text Available Non-wood fibers such as bamboo and wheat straw have been playing important roles in the pulp and paper industry in China. In this study an ECF-bleached bamboo kraft pulp was compared with a bleached softwood kraft pulp (NBSK as the reinforcement pulp in fine paper production. Areas that were examined include the refining of pure fibers, influence of bamboo on dewatering, retention, and sizing. The influence of bamboo kraft pulp as a part of a furnish replacing NBSK was compared as well. Results show that fiber shortening was more prominent with bamboo when refined. This resulted in a higher amount of fines, and addition wet-end chemicals may be required to compensate. Handsheets with bamboo as a reinforcement fiber showed similar mechanical and optical properties to handsheets containing NBSK.

  3. 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

  4. 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

  5. Comparison of pulping and bleaching behaviors of some agricultural residues

    OpenAIRE

    ATEŞ, Saim; DENİZ, İlhan; KIRCI, Hüseyin; ATİK, Celil; OKAN, Onur Tolga

    2015-01-01

    The present study determines the characteristics of bleaching and beating of annual plants and agricultural waste, which constitute important raw material potential for the pulp and paper industry in Turkey. It also examines the effects of this process on several paper properties. Firstly, chemical contents are determined for each raw material and then evaluated for use in the pulp and paper industry. All raw materials studied are found to be suitable for use in the pulp and paper industry, a...

  6. Evaluation of environmental policy instruments - a case study of the Finnish pulp and paper and chemical industries

    International Nuclear Information System (INIS)

    This research-based evaluation of environmental policy Instruments in Finland is focussed on regulatory instruments based on the Water Act, the Air Pollution Control Act and the Chemicals Act, on electricity taxation and on voluntary environmental management systems. The examined policy instruments have had several positive effects. They have directed major industrial point source polluters towards solving environmental problems. The transparency has been an important factor ensuring the success of the policy instruments and in avoiding the regulatory capture that could have thrived in a system largely based on negotiations between operators and authorities. The transparency has made it easy for Finnish firms to adopt environmental management systems and an open attitude to environmental reporting. The permit conditions have not directly resulted in innovations, but they have contributed to the diffusion of end-of-pipe technology and have contributed to innovations by expanding the market for environmentally better technical solutions. The permit systems have also indirectly contributed to innovations by creating a demand for environmental experts and environmental education. Networks have clearly developed as a consequence of and in response to regulatory instruments. These networks appear to have had their greatest significance prior to the permit procedures. The trend has been towards a greater emphasis of the communication in the networks prior to the presentation of an application in order to ensure a smoothly functioning permit process. In the networks contributing to innovations and the diffusion of innovations authorities have largely been outsiders, except when an innovation has become a de facto standard for permit conditions. The different kind of effects, the complexity of consequences and the uncertainties with respect to causes and effects mean that studies aiming at evaluating the overall worth and merit of an environmental policy instrument should

  7. Nutritional composition of Annona crassiflora pulp and acceptability of bakery products prepared with its flour

    Directory of Open Access Journals (Sweden)

    Paula Villela

    2013-09-01

    Full Text Available Annona crassiflora offers an edible fruit native to the Savanna. This study aimed to develop a flour meal from Annona crassiflora pulp; analyze the chemical composition of the fresh pulp and its flour; develop and verify the acceptance of formulations with different concentrations of the flour of Annona crassiflora pulp. Fruit used were selected and processed. The pulp was dried in an oven at 60-65 ºC/48h. We analyzed the chemical composition, and two formulations of breads were prepared with 10 and 20% Annona crassiflora pulp. The results showed that the drying of Annona crassiflora pulp enriched its nutritional value. The Annona crassiflora pulp showed important chemical components, as insoluble fibers (pulp and flour, minerals (potassium, calcium, manganese and others and antioxidant compounds. The formulations were well-accepted in a sensory point of view and proved to be a good alternative to the exploitation of the fruit.

  8. DENTAL PULP TISSUE ENGINEERING

    OpenAIRE

    Demarco, FF; Conde, MCM; Cavalcanti, B; Casagrande, L.; Sakai, V; Nör, JE

    2011-01-01

    Dental pulp is a highly specialized mesenchymal tissue, which have a restrict regeneration capacity due to anatomical arrangement and post-mitotic nature of odontoblastic cells. Entire pulp amputation followed by pulp-space disinfection and filling with an artificial material cause loss of a significant amount of dentin leaving as life-lasting sequelae a non-vital and weakened tooth. However, regenerative endodontics is an emerging field of modern tissue engineering that demonstrated promisin...

  9. Chemical composition and kraft pulping potential of 12 Eucalypt species%12种桉树化学成分分析及其硫酸盐法制浆适宜性评价

    Institute of Scientific and Technical Information of China (English)

    陈乐(编译); 龙柱(编译)

    2015-01-01

    桉树是一种重要的速生阔叶木,在全球广泛种植,主要用于制浆造纸工业。对12种6年生桉树的化学成分、纤维形态,制浆造纸性能进行分析,评价它们的硫酸盐法制浆适宜性。12种桉树在抽出物(6.1%~18.9%)、木素(21.6%~30.8%)和综纤维素(55.4%~70.1%)含量方面存在显著差异,化学成分方面的巨大差异导致了桉树不同的制浆得率(38.9%~49.8%)和脱木素程度(卡伯值11.6~24.2)。将这些结果与纤维形态、手抄纸性能综合考虑,蓝桉、卵叶桉、巨尾桉、柳桉、葡萄桉的硫酸盐法制浆适宜性最好。%Eucalypts are among the most important short-rotation hardwoods, planted worldwide for the pulp and paper industry. Six-year-old Eucalypt trees from 12species were analyzed for chemical composition, fiber morphological, pulping and handsheet paper properties to determine their kraft pulping suitability. The 12 species showed substantial differences regarding extractives (6.1%~18.9%), lignin (21.6%~30.8%) and holocellulose content (55.4%~70.1%). The high inter-species variation in chemical composition produced pulps with different yields (38.9%~49.8%) and degree of delignification (Kappa number 11.6~24.2). The combination of these results with the morphological and handsheet properties suggests that E. globulus, E. ovata, E. grandis, E. saligna and E. botryoides have the best overall characteristics for kraft pulping.

  10. Dental Pulp Testing: A Review

    OpenAIRE

    Eugene Chen; Paul V. Abbott

    2009-01-01

    Dental pulp testing is a useful and essential diagnostic aid in endodontics. Pulp sensibility tests include thermal and electric tests, which extrapolate pulp health from sensory response. Whilst pulp sensibility tests are the most commonly used in clinical practice, they are not without limitations and shortcomings. Pulp vitality tests attempt to examine the presence of pulp blood flow, as this is viewed as a better measure of true health than sensibility. Laser Doppler flowmetry and pulse o...

  11. Chemical and sensory characterization of orange (Citrus sinensis) pulp,a by-product of orange juice processing using gas-chromatography-olfactometry

    Science.gov (United States)

    Volatile composition of commercial orange pulp (from Brazil and Florida, U.S.A.) were analyzed by gas chromatography-mass spectrometry (GC-MS) and GC-Olfactometry (GC-O). In both samples 72 volatiles were detected, of which 58 were identified. Odor-active compounds with high frequency of detection (...

  12. Suitability of Sudanese Cotton Stalks for Alkaline Pulping with Additives

    Directory of Open Access Journals (Sweden)

    Tarig Osman Khider

    2012-01-01

    Full Text Available The fibre characteristics and chemical composition of Gossypium Hirsutum, Sudanese cotton stalks were assessed for their suitability for papermaking. Soda-anthraquinone (soda-AQ, alkaline sulphite-anthraquinone (AS-AQ and ASAM (alkaline sulphite-anthraquinone- methanol cookings were carried out with different alkali charges and pulps with acceptable to good yields and mechanical properties were obtained. ASAM pulping gave the best results in yields, degree of delignification, mechanical pulp properties. AS-AQ pulping cooking with ratio (70: 30 as NaOH: Na2SO3 gave better results compared to (60: 40 ratio.

  13. Biorefinery pulp mill - BiSe

    Energy Technology Data Exchange (ETDEWEB)

    Henricson, K.; Saukkonen, E.; Nokkanen, T. (and others) (Lappeenranta Univ. of Technology (Finland). Lab. of Fiber and Paper Technology). Email: kaj.henricson@lut.fi

    2010-10-15

    A need to utilize woody material in a more efficient way to produce pulp, biofuels and energy is seen as a key factor in the development of new pulp mill biorefineries. There are many alternatives to execute the biorefinery concept. In the Biorefinery Pulp Mill (Biojalostamo Sellutehdas), BiSe project approach, prehydrolysis of wood chips and acid hydrolysis of logging residue for the production of bioethanol as well as the separation of lignin for the production of biodiesel are studied. The main goal of the project is to examine these new biofuel production methods and processes for the improvement of the competitiveness, energy effectiveness and economic profitability of domestic pulp mills, while keeping in mind the main product, chemical pulp. In the project, laboratory experiments on wood chip prehydrolysis prior to cooking, hydrolysis liquor treatment, cooking of prehydrolyzed chips, low power pulp bleaching and lignin separation are carried out. Based on these laboratory data, a simulation model of the biorefinery is created. The model is then used to assess the profitability of the BiSe biorefinery approach. (orig.)

  14. Impact of kaolin filler on physical and mechanical paper properties formed by ECF pulp

    OpenAIRE

    Ivan Rodrigues dos Santos; Gustavo Ventorim; José Cláudio Caraschi; Jaqueline Silveira Comelato Favaro

    2014-01-01

    The paper industry is the main global consumer of kaolin. It is mostly used as paper filler, due to its lower cost as compared to pulp cost. Color removal process from pulp - chemical bleaching - determines final pulp's characteristics. Effort has been made to make possible to obtain less toxic bleaching processes. This study aims to evaluate the influence of three bleaching sequences, on kaolin retention and paper properties. Industrial eucalyptus kraft pulp, oxygen pre-delignified, was blea...

  15. 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

  16. Reductions in greenhouse gas emissions and oil use by DME (di-methyl ether) and FT (Fischer-Tropsch) diesel production in chemical pulp mills

    International Nuclear Information System (INIS)

    Using energy systems analysis, we examine the potential to reduce CO2 emissions and oil use by integrating motor biofuel production with pulp mills. BLG-DME (black liquor gasification with di-methyl ether production) is compared with solid biomass gasification with BIG-FT (solid biomass gasification with Fischer-Tropsch fuel production). The studied systems are expanded with stand-alone production of biomass-based electricity and motor fuel so that they yield the same functional unit in terms of motor fuel and electricity as well as pulp or paper product, in order to facilitate comparison. More motor biofuel can be produced in integration with the studied mills with BLG-DME than with BIG-FT because the black liquor flow is large compared with other fuel streams in the mill and the integration potential for BIG-FT is limited by the mill’s heat demand. When both systems are required to produce the same functional unit, the BLG-DME system achieves higher system efficiency and larger reductions in CO2 emissions and oil use per unit of biomass consumed. In general, integration of motor biofuel production with a pulp mill is more efficient than stand-alone motor biofuel production. Larger reductions in CO2 emissions or oil use can, however, be achieved if biomass replaces coal or oil in stationary applications. -- Highlights: ► CO2 emission and oil use reductions quantified for pulp mill-based biorefineries. ► Black liquor gasification gives larger reductions than solid biomass gasification. ► Lower mill steam demand increases the black liquor gasification advantage. ► Biomass directly replacing coal or oil in stationary plants gives larger reductions.

  17. OPTIMIZING EUCALYPTUS PULP REFINING

    Institute of Scientific and Technical Information of China (English)

    Vail Manfredi

    2004-01-01

    This paper discusses the refining of bleached eucalyptus kraft pulp (BEKP).Pilot plant tests were carried out in to optimize the refining process and to identify the effects of refining variables on final paper quality and process costs.The following parameters are discussed: pulp consistency, disk pattern design, refiner speed,energy input, refiner configuration (parallel or serial)and refining intensity.The effects of refining on pulp fibers were evaluated against the pulp quality properties, such as physical strengths, bulk, opacity and porosity, as well as the interactions with papermaking process, such as paper machine runnability, paper breaks and refining control.The results showed that process optimization,considering pulp quality and refining costs, were obtained when eucalyptus pulp is refined under the lowest intensity and the highest pulp consistency possible. Changes on the operational refining conditions will have the highest impact on total energy requirements (costs) without any significant effect on final paper properties.It was also observed that classical ways to control the industrial operation, such as those based on drainage measurements, do not represent the best alternative to maximize the final paper properties neither the paper machine runability.

  18. Pulping and paper properties of Palmyra palm fruit fibers

    Directory of Open Access Journals (Sweden)

    Waranyou Sridach

    2010-05-01

    Full Text Available Palmyra palm fruit fibers have the properties to be used as an alternative raw material of cellulosic pulps for papermaking.Acid and alkali pulping were investigated by using nitric acid and caustic soda on a laboratory scale, with the purpose of producing printing or writing grade pulp. The chemical composition of fiber strands from palmyra palm fruits were examined, such as holocellulose, cellulose, pentosan, lignin and extractives. The yields of acid and soda pulps were below 40%. The main physical and mechanical properties of hand sheets produced from acid and soda processes were evaluated on 80 g/m2 test sheets as functions of the following parameters: tensile index, tear index, and brightness. The mechanical properties of soda pulps were developed by twin-roll press while it was not necessary to fibrillate acidic pulps through the beating step. The soda pulp sheets presented a lower brightness than that of acidic pulp sheets. The mechanicaland physical properties of the acidic and alkaline pulps verified that they were of an acceptable quality for papermaking.

  19. Application of enzyme for improvement of Acacia APMP pulping and refining of mixed pulp for printing papermaking in Vietnam.

    Science.gov (United States)

    Dien, Le Quang; Hoang, Phan Huy; Tu, Do Thanh

    2014-02-01

    This study assesses the influence of commercial enzyme (FibreZyme LBR) treatment applied to APMP pulp and to the mixture of 55% Acacia CTMP75 pulp, 30% soft-wood bleached chemical pulp (LBKP 90 from Chile) and 15% hard-wood bleached chemical pulp (NPKP 90 from Indonesia). The treatment was conducted at different temperatures, reaction times and enzyme dosages. The APMP and mixed pulp treated with the enzyme showed a significant decrease of refining time to achieve the same refining degree (Schopper-Riegler freeness, °SR) and better mechanical-physical properties due to the development of fibrillation. The fibre morphology difference between before and after treatment was revealed by the microscopic observations performed by a scanning electron microscope (SEM). The SEM analysis showed that the surface of the enzyme-treated fibre had some swelling and fibrillar phenomenon that lead to strong paper properties such as tear index, tensile index and burst index. PMID:24222497

  20. Effects of Different Chemical by Adding the Bacterial Cellulose in Pulp%不同化学品对细菌纤维素配抄针叶木浆性能的影响

    Institute of Scientific and Technical Information of China (English)

    吕瑾; 王志杰; 刘叶; 石建博

    2012-01-01

    It studied the effects of different chemical for the electrochemical properties such as pH, electric conductivity rate, Zeta electric potential, demand of cation and so on, and the paper physical strength of the pulp with the bacterial cellulose. The result showed that adding Al2(SO4)3 and CPAM could change the eletrochemical properties of the pulp with the bacterial cellulose, and increas the physical strength of the paper obviously.%研究细菌纤维素配抄针叶木浆后添加不同化学品对浆料pH值、电导率、Zeta电位、阳离子需求量等电化学性质和成纸物理强度的影响。结果表明,细菌纤维素表面呈强负电性,在加了细菌纤维素的针叶木浆料系统中加入一定量的硫酸铝或CPAM,可以调节其电化学性能,使成纸物理强度增加更为明显.

  1. OPTIMIZING EUCALYPTUS PULP REFINING

    Institute of Scientific and Technical Information of China (English)

    VailManfredi

    2004-01-01

    This paper discusses the refining of bleachedeucalyptus kraft pulp (BEKP).Pilot plant tests were carded out in to optimize therefining process and to identify the effects of refiningvariables on final paper quality and process costs.The following parameters are discussed: pulpconsistency, disk pattern design, refiner speed,energy input, refiner configuration (parallel or serial)and refining intensity.The effects of refining on pulp fibers were evaluatedagainst the pulp quality properties, such as physicalstrengths, bulk, opacity and porosity, as well as theinteractions with papermaking process, such as papermachine runnability, paper breaks and refiningcontrol.The results showed that process optimization,considering pulp quality and refining costs, wereobtained when eucalyptus pulp is refined under thelowest intensity and the highest pulp consistencypossible. Changes on the operational refiningconditions will have the highest impact on totalenergy requirements (costs) without any significanteffect on final paper properties.It was also observed that classical ways to control theindustrial operation, such as those based on drainagemeasurements, do not represent the best alternative tomaximize the final paper properties neither the papermachine runability.

  2. 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.

  3. Pollution prevention in the pulp and paper industry

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, P.G. [Science Applications International Corp., Olympia, WA (United States)

    1995-09-01

    Probably no other industry has made as much progress as the kraft pulp and paper industry in reclaiming waste products. About half of the wood used in making pulp is cellulose; the reclamation of the other ingredients in the wood constitutes a continuing evolution of pollution prevention and economic success. The by-products of chemical pulping include turpentine used in the paint industry, lignosulfonates used as surfactants and dispersants, ``tall oil`` used in chemical manufacturing, yeast, vanillin, acetic acid, activated carbon, and alcohol. Sulfamic turpentine recovered in the kraft process is used to manufacture pine oil, dimethyl sulfoxide (DMSO), and other useful chemical products. In addition, the noncellulose portion of the wood is used to provide energy for the pulping process through the combustion of concentrated black liquor. Over 75% of the pulp produced in the US is manufactured using the kraft process. Because of the predominance of the kraft process, the remainder of this section will address pollution prevention methods for kraft pulp and paper mills. Some of these techniques may be applicable or adaptable to other pulping processes, especially sulfite mills. The major steps in the kraft process are described, followed by a discussion of major wastestreams, and proven pollution prevention methods for each of these steps.

  4. High-energy electron irradiation of annual plants (bagasse) for an efficient production of chemi-mechanical pulp fibers

    Science.gov (United States)

    Pathak, Shailesh; Ray, A. K.; Großmann, Harald; Kleinert, Rene

    2015-12-01

    The paper industry is one of the largest consumers of energy and energy consumption has been increased several times in last few decades. Bagasse chemical pulping has very low yield about 45-55% and also generates high pollution load in the effluent as compared to mechanical pulping, g. Thermo-mechanical pulp (TMP). On the other hand,-->e.g. thermo-mechanical pulp (TMP). On the other hand, the specific energy consumption is very high for TMP pulps. ETMP (Energy efficient Thermo-Mechanical Pulping) or ECTMP (Energy efficient Chemi-Thermo Mechanical Pulping) is an innovative idea for reducing the energy demand in TMP refining. In the present investigation, energy efficient mechanical pulping potential of bagasse was studied using TMP, CTMP and ECTMP pulping methodology with electron irradiation pretreatment. It is evident from the results that more than 50% energy saving potential of irradiation pre-treatment was achieved.

  5. Extended impregnation kraft cooking of softwood : Effects on reject, yield, pulping uniformity, and physical properties

    OpenAIRE

    Karlström, Katarina

    2009-01-01

    Converting wood into paper is a complex process involving many different stages, one of which is pulping. Pulping involves liberating the wood fibres from each other, which can be done either chemically or mechanically. This thesis focuses on the most common chemical pulping method, the kraft cooking process, and especially on a recently developed improvement of the impregnation phase, which is the first part of a kraft cook. Extended impregnation kraft cooking (EIC) technique is demonstrated...

  6. Avoiding total reduced sulfur (TRS) emissions from sodium sulfite pulping recovery processes

    International Nuclear Information System (INIS)

    This paper reports that one of the current trends in paper-making with cellulose pulping is the use of high-yield processes. With yields greater than 65%, these processes include mechanical pulps (groundwood and thermomechanical pulps or TMP), and semichemical types (chemi-TMP or CTMP). Groundwood and TMP make up about 10% of North American pulp production. Semichemical pulp makes up about 7% and is mostly used for corrugating medium. High-yield pulping for linerboard, particularly using the alkaline sulfite process, is also likely to be used in the future. High-yield pulping is based primarily on the sulfite process using mostly sodium-based chemicals. A disadvantage of this process is the unavailability of a recovery system for the inorganic pulping chemicals. Generally, mills have not accepted any particular recovery system for this process. For this and other reasons, sulfite processes constitute only 3-4% of the total North American pulp production. If high-yield processes continue to increase in popularity, a sodium sulfite chemical recovery system will be needed. A number of chemical recovery systems have been developed in the past 30 years for sodium-based sulfite pulping processes, with most of the mills successfully using this process located in Scandinavia

  7. EVALUATION OF PULP AND PAPER MAKING CHARACTERISTICS OF RICE STEM FIBERS PREPARED BY TWIN-SCREW EXTRUDER PULPING

    Directory of Open Access Journals (Sweden)

    Alireza Talebizadeh

    2010-06-01

    Full Text Available Twin-screw extrusion pulping is a new approach to the manufacture of pulp for paper production, designed for non-wood feedstocks. In this research, the production of pulp from rice stem with a newly fabricated twin-screw extruder was investigated. Extrusion pulping of rice stem was conducted following a central composite design using a two-level factorial plan involving three process variables (pretreatment NaOH concentration: 0.4, 0.8, 1.2%; extrusion temperature: 40, 60, 80 oC; and extruder rotational speed: 55, 70, 85 rpm. Responses of pulp and handsheets properties to the process variables were analyzed using statistical software (MINITAB 15. As the results show, pulping of rice stem fiber can be done at a relatively short pretreatment time about 4 hours and a low NaOH concentration about 0.8% by twin-screw extruder with limit extrusion temperature of about 80 oC and extruder rotational speed about 85 rpm. The effect of pretreatment solvent, NaOH, is greatly enhanced by increases in the extrusion temperature. Analysis of the results revealed that this process has suitable potential to be used to obtain a pulp with yields approximately equivalent to neutral sulfite semi-chemical pulping at fixed kappa number, which is applicable for fluting paper and linerboard production.

  8. Evaluation of hydropyrolysis as an energy-saving alternative to the Tomlinson furnace. Task III. Chemical causes of increased pulp yield

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    The yield-enhancing effect was found to be the result of the presence of small but significant levels of polysulfide and calcium ions. Polysulfide ions are generated during the causticization of the hydropyrolysis filtrate and is the result of a partial-air oxidation of Na/sub 2/S that occurs under conditions existing during the causticizing process. In the presence of residual organics, calcium ions are complexed to form soluble calcium-organo complexes which allow for a carryover of a significant amount of calcium into the final cooking liquor. The presence of both ions in the final cooking liquor allow for pulp yield increases through the formation of alkali-stable aldonic acid end-groups which protect carbohydrates from alkaline-degradation.

  9. INCORPORATION OF BARK AND TOPS IN EUCALYPTUS GLOBULUS WOOD PULPING

    Directory of Open Access Journals (Sweden)

    Isabel Miranda,

    2012-07-01

    Full Text Available Bark and the tops of E. globulus trees were considered for kraft pulping under industrial conditions. Pulping experiments included wood, bark, tops, and composite samples. Top wood had an average chemical composition most similar to that of wood but with somewhat lower cellulose content (52.8% vs. 56.9% and higher lignin content (18.8% vs. 17.8%. There was also a small difference between tops and wood for non-polar extractives, which were higher for tops (2.0% vs. 1.4%. Bark had a less favorable chemical composition with more extractives, especially polar extractives (5.3% vs. 1.6% and 1% NaOH solubility (19.9% vs. 12.2%, pentosans (23.7% vs. 21.3%, and ash (2.9% vs. 1.0%, although the fiber length was higher (1.12 mm vs. 0.98 mm. The kraft pulps obtained using bark showed significantly lower yield, delignification degree, and strength properties but had a quicker response to refining. The incorporation of tops and bark in the wood pulping in levels below or similar to a corresponding whole-stem, however, had a limited effect on pulp yield, kappa number, refining, and pulp strength properties. These additional raw-materials, which were estimated to be 26% of the commercial stem wood (14% bark and 12% tops, may therefore be considered in enlarging the eucalypt fiber feedstock in kraft pulping.

  10. Sisal organosolv pulp as reinforcement for cement based composites

    Directory of Open Access Journals (Sweden)

    Ana Paula Joaquim

    2009-09-01

    Full Text Available The present work describes non-conventional sisal (Agave sisalana chemical (organosolv pulp from residues of cordage as reinforcement to cement based materials. Sisal organosolv pulp was produced in a 1:1 ethanol/water mixture and post chemically and physically characterized in order to compare its properties with sisal kraft pulp. Cement based composites reinforced with organosolv or kraft pulps and combined with polypropylene (PP fibres were produced by the slurry de-watering and pressing method as a crude simulation of the Hatschek process. Composites were evaluated at 28 days of age, after exposition to accelerated carbonation and after 100 soak/dry cycles. Composites containing organosolv pulp presented lower mechanical strength, water absorption and apparent porosity than composites reinforced with kraft pulp. The best mechanical performance after ageing was also achieved by samples reinforced with kraft pulp. The addition of PP fibres favoured the maintenance of toughness after ageing. Accelerated carbonation promoted the densification of the composites reinforced with sisal organosolv + PP fibres.

  11. Estabilidade química, físico-química e microbiológica de polpas de acerola pasteurizadas e não-pasteurizadas de cultivo orgânico Chemical, physicochemical and microbiological stability of pasteurized and non pasteurized acerola pulps from organic cultivation

    Directory of Open Access Journals (Sweden)

    Rafaela Maria Temóteo Lima

    2012-02-01

    Full Text Available O presente trabalho objetivou avaliar a estabilidade química, físico-química e microbiológica de polpas de acerola pasteurizadas e não-pasteurizadas, oriundas de cultivo orgânico e armazenadas sob congelamento (-18±2°C durante 360 dias. O armazenamento sob congelamento não ocasionou perdas significativas de qualidade das polpas de acerola. No entanto, o tratamento térmico influenciou negativamente nos conteúdos iniciais de alguns componentes, principalmente sólidos solúveis, açúcares solúveis totais e redutores, que apresentaram conteúdos inferiores no início do armazenamento para as polpas pasteurizadas. As polpas pasteurizadas e não-pasteurizadas apresentaram boa qualidade microbiológica do início ao final do armazenamento. Dentre as polpas estudadas, as polpas não-pasteurizadas apresentaram melhores características iniciais de cor. As polpas pasteurizadas garantiram melhores características microbiológicas no que concerne aos aspectos de segurança alimentar.The present research aimed to evaluate the chemical, physical-chemical and microbiological stability of pasteurized and non-pasteurized acerola pulp coming from organic cultivation stored frozen for 360 days. Storage under freezing did not cause significant loss of acerola pulp's quality. However, the heat treatment had a negative influence on the initial contents of some components, especially soluble solids, total soluble and reducing sugars, which showed lower contents at the beginning of storage for pasteurized pulp. Among the pulps studied, non-pasteurized pulps showed the best characteristics of the initial color. The pasteurized pulps guaranteed best features in regard to the microbiological aspects of food safety.

  12. ON THE RECOVERY OF HEMICELLULOSE BEFORE KRAFT PULPING

    Directory of Open Access Journals (Sweden)

    Carlos Vila,

    2012-07-01

    Full Text Available To assess the feasibility of implementing hemicellulose recovery stages in kraft mills, Eucalyptus globulus wood samples were subjected to aqueous treatments with hot, compressed water (autohydrolysis processing to achieve partial dissolution of xylan. Autohydrolyzed solids were subjected to kraft pulping under selected conditions to yield a pulp of low kappa number, and to an optimized TCF bleaching sequence made up of three stages (alkaline oxygen delignification, chelating, and pressurized hydrogen peroxide, with minimized additions of pulping and bleaching chemicals. The final product had a relatively low kappa number (1.4, 641 mL/g ISO intrinsic viscosity, and 86.4% brightness.

  13. Simulation and Optimization of a Generic Kraft Pulp Mill

    OpenAIRE

    Barahona Vazquez, Javier

    2010-01-01

    The Canadian pulp and paper industry is going through an economic crisis mainly due to a decrease of world demand and aggressive competition from emerging nations. In this context, the forest biorefinery which can be defined as the “full integration of the incoming biomass and other raw materials, including energy, for simultaneous production of fibres for paper products, chemicals and energy”, is one of the solutions for pulp and paper mills to diversify their core business and regain compet...

  14. Nutritional composition of Annona crassiflora pulp and acceptability of bakery products prepared with its flour

    OpenAIRE

    Paula Villela; Ângela Giovana Batista; Nísia Andrade Villela Dessimoni-Pinto

    2013-01-01

    Annona crassiflora offers an edible fruit native to the Savanna. This study aimed to develop a flour meal from Annona crassiflora pulp; analyze the chemical composition of the fresh pulp and its flour; develop and verify the acceptance of formulations with different concentrations of the flour of Annona crassiflora pulp. Fruit used were selected and processed. The pulp was dried in an oven at 60-65 ºC/48h. We analyzed the chemical composition, and two formulations of breads were prepared with...

  15. PULPING PROPERTIES OF KRAFT PULP OF NIGERIAN-GROWN KENAF (HIBISCUS CANNABINUS L.

    Directory of Open Access Journals (Sweden)

    Abiodun Oluwafemi Oluwadare

    2011-02-01

    Full Text Available This study was centered on finding a locally sourced alternative to imported long-fibre pulp for Nigerian pulp and paper mills. Fibre characteristics, chemical composition, and paper properties of pulp handsheets at different levels of kappa number and freeness in the range of 10 oSR and 62 oSR were evaluated using air-dried bast fibre obtained from decorticated kenaf plants grown in southern guinea savanna near Jebba, Nigeria. Kenaf bast fibre compared well with softwood, with an average fibre length of 2.90 mm, a flexibility ratio of 57%, and a Runkel ratio of 0.76. Ash, lignin, and pentosan contents were 0.6%, 12.5%, and 10.6%, respectively, while the cellulose content was 55.5%. Under alkali charge of 15.0 and, sulphidity of 17.5 with constant temperature, cooking time, and liquor-to-fibre ratio of 4.5:1, the screen yield was between 48.8 to 52.8 % with kappa number 12.04 to 20.5. Unbleached pulpsheets at kappa number between 15 and18.5 and pulp freeness 55 oSR and bleached pulp freeness between 148 and 336 mLs had better quality paper in terms of overall pulpsheet strength properties.

  16. EFFECTS OF ALKALINE PRE-IMPREGNATION AND PULPING ON MALAYSIA CULTIVATED KENAF (HIBISCUS CANNABINUS

    Directory of Open Access Journals (Sweden)

    Lin Suan Ang

    2010-05-01

    Full Text Available This study was carried out to identify an appropriate alkaline pulping condition for Malaysia cultivated kenaf (Hibiscus cannabinus L.. The chemical composition of the kenaf bast and core fibers, and also whole stalk with different growing time were examined prior to pulping attempts. The results of various soda-AQ pulping showed that the degree of carbohydrate degradation and delignification increased with the increase of active alkali and cooking temperature, but decreased with the increase of liquor to material (L:M ratio. The most satisfactory properties of pulp and handsheets from bast could be attained by employing soda-AQ pulping with 19.4% active alkali, 0.10% AQ, and L:M ratio of 7:1 cooked for 2 hours at 160˚C. Besides, it was also found that a mild alkaline pre-impregnation prior pulping improved the pulp viscosity and handsheets’ strength properties, especially the tensile index and folding endurance effectively. Moreover, among the three alkaline pulping processes—kraft, kraft-AQ, and soda-AQ—the results of pulp and handsheet properties showed that the soda-AQ pulp was comparable or even slightly of higher quality than the kraft pulps. Between the unbeaten bast and core soda-AQ handsheets, the strength properties of the core were higher than the bast, as the thin-walled core fibers exhibited much better conformability than the thick-walled bast fibers.

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

    OpenAIRE

    Costa, M. M.; Colodette, J.L.

    2007-01-01

    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 oxy...

  18. 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.

  19. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

    OpenAIRE

    Letizia Ferroni; Chiara Gardin; Stefano Sivolella; Giulia Brunello; Mario Berengo; Adriano Piattelli; Eriberto Bressan; Barbara Zavan

    2015-01-01

    Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D) hyaluronan scaffold and human dental pulp stem cells (DPSCs) to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyalur...

  20. APPLICATION OF ALKALINE SULFITE PULPING ON CORN STALKS

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    Ahmad Jahan Latibari

    2011-02-01

    Full Text Available Alkaline sulfite pulping of corn stalks was investigated to produce supplementary pulp for corrugating board manufacture. Three pulping temperatures (125, 145, and 165°C and five active alkali charges (10, 12, 14, 16, and 18% were used. Cooking time at 30 minutes, Na2SO3/ NaOH ratio at 50:50, and liquor to residue ratio of 8:1 were kept constant. The highest total yield (61.9% was reached applying the treatment combination of 125°C and 10% active alkali, and the lowest total yield (42.5% was related to 165°C and 16% chemical. The influence of sodium sulfite/sodium hydroxide ratios was studied applying different ratios (30:70, 40:60, 50:50, 60:40, and 70:30 at constant time and temperature of 30 minutes and 145°C respectively and 14 and 16% active alkali. Pulping condition; 16% active alkali, 30 minutes time, 145°C pulping temperature and varying ratios of sodium sulfite/sodium hydroxide were selected for pulp strength evaluation. The results of handsheet evaluation indicated that 16% active alkali, 30 minutes pulping at 145ºC and sodium sulfite/sodium hydroxide ratio of 50:50 is the optimum pulping condition for corn stalks. Tear, tensile, and burst indices and breaking length of this pulp were measured as 10.53 mN.m2g-1, 62.4 N.mg-1, 3.80 kPa.m2g-1, and 6.07 km, respectively.

  1. Integration of water footprint accounting and costs for optimal pulp supply mix in paper industry

    DEFF Research Database (Denmark)

    Manzardo, Alessandro; Ren, Jingzheng; Piantella, Antonio;

    2014-01-01

    studies have focused on these aspects, but there have been no previous reports on the integrated application of raw material water footprint accounting and costs in the definition of the optimal supply mix of chemical pulps from different countries. The current models that have been applied specifically...... mix that minimizes the water footprint accounting results and costs of chemical pulp, thereby facilitating the assessment of the water footprint by accounting for different chemical pulps purchased from various suppliers, with a focus on the efficiency of the production process. Water footprint...... accounting was adapted to better represent the efficiency of pulp and paper production. A multi-objective model for supply mix optimization was also developed using multi-criteria decision analysis (MCDA). Water footprint accounting confirmed the importance of the production efficiency of chemical pulp...

  2. TECHNOLOGICAL CHARACTERIZATION OF Eucalyptus benthamii WOOD FOR KRAFT PULP PRODUCTION

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Nogueira Alves

    2011-03-01

    Full Text Available The purpose of this study was to evaluate the quality of Eucalyptus benthamii wood for kraft pulp production. A hybrid of Eucalyptus urophylla x Eucalyptus grandis, probably the most planted Eucalyptus clone in Brazil, was also analyzed for comparison purposes. Basic density, chemical composition and fiber dimensions were determined for the two species. The Eucalyptus benthamii wood presented an anatomical structure, basic density and fiber dimensions quite similar to those of other species planted by the Brazilian pulp industry. However, it presented poorer wood quality characteristics when compared to the hybrid urograndis species, with higher amounts of extractives and lignin, lower amount of glucans, more galactans and lower S/G ratio, characteristics leading to lower pulping yield. Additional studies should be carried out to establish its pulping, bleaching and paper strength properties.

  3. EFFECT OF DIFFERENT HLB VALUE AND ENZYMATIC TREATMENT ON THE PROPERTIES OF OLD NEWSPAPER DEINKED PULP

    Directory of Open Access Journals (Sweden)

    Nader Mayeli

    2010-11-01

    Full Text Available Current deinking processes use potentially environmentally damaging chemicals in large quantities. The use of enzymes could be an attractive alternative to certain other chemicals used in deinking. In this research, the effects of different HLB (hydrophile-lipophile balance values and enzymatic treatments on the deinking of old newspaper pulp (ONP was studied, and optical properties and mechanical strengths of deinked pulps (DIP were determined. Enzymatic treatments of old newspaper pulps were performed at two temperatures, 20°C and 50°C. Nonionic surfactants with different HLB values were used as the flotation agent. The flotation was conducted for pulps with and without enzymatic treatment. The results showed that brightness values for the floated pulp without enzyme treatment were slightly greater than for the enzyme-treated deinked pulp. Also, dirt count for treated pulps with commercial cellulase and floated with ethoxylated fatty alcohol of HLB 12 at 50°C was lower than that of other pulps. The mechanical strengths of the enzymatically deinked pulps, in terms of burst, tensile, folding endurance, E-MOD, and elongation, were increased, but tear strength for the floated pulps with ethoxylated fatty alcohol of HLB 12 was increased at 50°C without enzymatic treatment. Also, the deinking efficiency of handsheets made from treated pulps with commercial cellulase and ethoxylated fatty alcohol of HLB 12 was highest. The treated pulps with enzyme only, with a combination of commercial cellulase and lipase at 50°C, showed the lowest freeness value in comparison with other pulps.

  4. Direct pulp capping using biodentine

    Directory of Open Access Journals (Sweden)

    Popović-Bajić Marijana

    2014-01-01

    Full Text Available Introduction. Direct pulp capping is therapeutic method of applying medication on exposed pulp in order to allow bridge formation and healing process. The aim of this study was to investigate the effect of Biodentine on exposed dental pulp of Vietnamese pigs. Material and Methods. The study was conducted on 20 teeth of Vietnamese pigs (Sus scrofa domesticus. On buccal surfaces of incisors, canines and first premolars, class V cavities were prepared and pulp was exposed. In the experimental group (six incisors, two canines and two premolars the perforation was covered with Biodentine® (Septodont, Saint-Maur-des-Fosses, France. In the control group, the perforation was covered with MTA® (Dentsply Tulsa Dental, Johnson City, TN, USA. All cavities were restored with glass ionomer cement (GC Fuji VIII, GC Corporation, Tokyo, Japan. Observation period was 28 days. After sacrificing the animals, histological preparations were done to analyze the presence of dentin bridge, an inflammatory reaction of the pulp, pulp tissue reorganization and the presence of bacteria. Results. Dentin bridge was observed in all teeth (experimental and control groups. Inflammation of the pulp was mild to moderate in both groups. Neoangiogenesis and many odontoblast like cells responsible for dentin bridge formation were detected. Necrosis was not observed in any case, neither the presence of Gram-positive bacteria in the pulp. Conclusion. Histological analysis indicated favorable therapeutic effects of Biodentine for direct pulp capping in teeth of Vietnamese pigs. Findings were similar with Biodentine and MTA.

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

    International Nuclear Information System (INIS)

    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)

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Composição química e compostos bioativos presentes na polpa e na amêndoa do pequi (Caryocar brasiliense, Camb. Chemical composition and bioactive compounds in the pulp and almond of pequi fruit

    Directory of Open Access Journals (Sweden)

    Alessandro de Lima

    2007-01-01

    Full Text Available O conhecimento da composição química dos alimentos é fundamental para se avaliarem a disponibilidade de nutrientes e o seu consumo por populações. Neste trabalho, o pequi (Caryocar brasiliense, Camb. foi caracterizado pela composição centesimal e pela presença de compostos bioativos na polpa e na amêndoa. Os dados do perfil lipídico mostram alto teor de lípides tanto na polpa quanto na amêndoa, destacando-se nos mesmos a presença dos ácidos graxos insaturados, predominando o ácido oléico como principal componente entre os ácidos graxos. Foi observada também a relação entre os elevados teores de ácidos graxos insaturados com os compostos fenólicos e carotenóides presentes, tendo a polpa quantidades mais expressivas dessas substâncias quando comparada à amêndoa, além de conter uma quantidade superior de fibra alimentar. Os resultados obtidos abrem a perspectiva de se utilizar o pequi como fruto que apresenta, na sua composição, compostos importantes para a formulação de uma dieta saudável.The knowledge of the chemical composition of foods is basic for evaluate the nutrients availability and its consumption for the population. In this work, the pulp and the almond of pequi fruit (Caryocar brasiliense, Camb. were characterized by the centesimal composition and the presence of nutrients. The results showed high amount of lipids and in the fatty acids profile, the oleic fatty acid was the main component. The presence between high unsaturated fatty acids and antioxidant compounds (phenolic acids and carotenoids was correlated with the fruit protection. In the pulp was observed too high amount of alimentary fiber. These results are suggesting the pequi utilization in a healthful diet preparation.

  8. DISSOLVING PULP PRODUCTION FROM BAMBOO

    Directory of Open Access Journals (Sweden)

    Larisse Aparecida Ribas Batalha,

    2011-12-01

    Full Text Available Commercial bamboo chips were evaluated as raw material for dissolving pulp production. The chips were auto-hydrolyzed (AH and subsequently cooked by the NaOH/AQ process and bleached to full brightness with the O-CCE-D-(EP-D-P sequence. The term CCE designates a cold caustic extraction stage. The bamboo chip chemistry (22.4% lignin, 19.5% xylans, 49.3% cellulose, 16.8% total extractives, and 1.5% ash was apparently unfavorable; however high quality dissolving pulp was produced using the aforementioned technologies, even when compared to results obtained with traditional eucalypt commercial wood chips. The pulp showed high brightness (92.4 % ISO and α-cellulose content (94.9%. Its contents of hemicelluloses, extractives and ash were within acceptable levels for a dissolving pulp aimed at viscose rayon production. Thus, the bamboo chip furnish investigated can be regarded as a viable raw material for dissolving pulp production.

  9. ECF AND TCF BLEACHING OF SECONDARY FIBER PULP

    Directory of Open Access Journals (Sweden)

    Gustavo Ventorim

    2009-09-01

    Full Text Available In this study, ECF and TCF bleaching processes were evaluated for the bleaching of a deinked mixed office waste (MOW pulp sample produced in a pilot plant. The sample was bleached by all processes to a target brightness of 78 % ISO minimum. The results were interpreted on the basis of chemical cost to reach the target brightness, bleaching yield and bleached pulp quality as measured by viscosity, fluorescence and b* color coordinate. Among the ECF sequences, the mosattractive was the DEDD which showed the lowest chemical cost and produced bleached pulp of high quality as measured by viscosity, fluorescence and b* coordinate. The best TCF sequence with ozone was the Q(PO(ZQ(PO which resulted in very high brightness ceiling. This sequence decreased moderately the pulp b* coordinate and viscosity and slightly its fluorescence. Among the TCF sequences without ozone the Q(POQ(PO was the most effective but showed poor flexibility with regard to brightness ceiling. This sequence had little effect on pulp viscosity, fluorescence and b* coordinate. For all three  bleaching processes, it was determined that process yield is negatively affected by hot alkaline stages such as O, P and (PO.

  10. Characterization of active paper packaging incorporated with ginger pulp oleoresin

    Science.gov (United States)

    Wiastuti, T.; Khasanah, L. U.; Atmaka Kawiji, W.; Manuhara, G. J.; Utami, R.

    2016-02-01

    Utilization of ginger pulp waste from herbal medicine and instant drinks industry in Indonesia currently used for fertilizer and fuel, whereas the ginger pulp still contains high oleoresin. Active paper packaging were developed incorporated with ginger pulp oleoresin (0%, 2%, 4%, and 6% w/w). Physical (thickness, tensile strength, and folding endurance, moisture content), sensory characteristics and antimicrobial activity of the active paper were evaluated. Selected active paper then were chemically characterized (functional groups). The additional of ginger pulp oleoresin levels are reduced tensile strength, folding endurance and sensory characteristic (color, texture and overall) and increased antimicrobial activity. Due to physical, sensory characteristic and antimicrobial activity, active paper with 2% ginger pulp oleoresin incorporation was selected. Characteristics of selected paper were 9.93% of water content; 0.81 mm of thickness; 0.54 N / mm of tensile strength; 0.30 of folding endurance; 8.43 mm inhibits the growth of Pseudomonas fluorescence and 27.86 mm inhibits the growth of Aspergillus niger (antimicrobial activity) and neutral preference response for sensory properties. For chemical characteristic, selected paper had OH functional group of ginger in 3422.83 cm-1 of wave number and indicated contain red ginger active compounds.

  11. INTEGRATION OF KRAFT PULPING ON A FOREST BIOREFINERY BY THE ADDITION OF A STEAM EXPLOSION PRETREATMENT

    Directory of Open Access Journals (Sweden)

    Raquel Martin-Sampedro

    2011-02-01

    Full Text Available Steam explosion has been proposed for a wide range of lignocellulosic applications, including fractionation of biomass, pre-treatment of biomass for ethanol production, or as an alternative to conventional mechanical pulping. Nevertheless, a steam explosion process could also be used as pretreatment before chemical pulping, expecting a reduction in cooking time due to the open structure of the exploded chips. Thus, to evaluate the effect of steam explosion as a pretreatment in the kraft pulping of Eucalyptus globulus, steam exploded chips and control chips were subjected to kraft cookings. Steam exploded chips provided pulps with reductions of kappa number by up to 70% with no significant change in viscosity. Therefore, the cooking time could be shortened by 60%, increasing the productivity and obtaining pulps with similar delignification degree to those of the control pulp. Furthermore, not only the production rate could be increased, but also most of the hemicelluloses could be recovered before pulping and converted to a value-added product. Finally, although exploded pulp had inferior mechanical strength, the optical properties, which are more important in eucalyptus pulps, were found to be better.

  12. Electron beam radiation treatment of pulp bleaching effluent

    International Nuclear Information System (INIS)

    There are very high values of the chemical oxidation demand (COD) in the effluent from pulp mills. The COD value of the effluent is still higher after traditional biological treatment. The biologically treated wastewater from pulp mill was irradiated using low energy EB. For the wastewater irradiated with a dose of less than 1 kGy, its COD value was reduced to 1/4 of the value for unirradiated wastewater. Chromaticity of the irradiated-wastewater was also greatly decreased. The UV-visible spectra of a significant constituent of the wastewater indicated that the contaminants were degraded well

  13. Method of treating contaminated HEPA filter media in pulp process

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Jian S.; Argyle, Mark D.; Demmer, Ricky L.; Mondok, Emilio P.

    2003-07-29

    A method for reducing contamination of HEPA filters with radioactive and/or hazardous materials is described. The method includes pre-processing of the filter for removing loose particles. Next, the filter medium is removed from the housing, and the housing is decontaminated. Finally, the filter medium is processed as pulp for removing contaminated particles by physical and/or chemical methods, including gravity, flotation, and dissolution of the particles. The decontaminated filter medium is then disposed of as non-RCRA waste; the particles are collected, stabilized, and disposed of according to well known methods of handling such materials; and the liquid medium in which the pulp was processed is recycled.

  14. Use of Coffee Pulp and Minerals for Natural Soil Ameliorant

    Directory of Open Access Journals (Sweden)

    Pujiyanto Pujiyanto

    2007-05-01

    Full Text Available In coffee plantation, solid waste of coffee pulp is usually collected as heap nearby processing facilities for several months prior being used as compost. The practice is leading to the formation of odor and liquid which contaminate the environment. Experiments to evaluate the effect of natural soil ameliorant derived from coffee pulp and minerals were conducted at The Indonesian Coffee and Cocoa Research Institute in Jember, East Java. The experiments were intended to optimize the use of coffee pulp to support farming sustainability and minimize negative impacts of solid waste disposal originated from coffee cherry processing. Prior to applications, coffee pulp was hulled to organic paste. The paste was then mixed with 10% minerals (b/b. Composition of the minerals was 50% zeolite and 50% rock phosphate powder. The ameliorant was characterized for their physical and chemical properties. Agronomic tests were conducted on coffee and cocoa seedling. The experiments were arranged according to Randomized Completely Design with 2 factors, consisted of natural ameliorant and inorganic fertilizer respectively. Natural ameliorant derived from coffee pulp was applied at 6 levels: 0, 30, 60, 90, 120 and 150 g dry ameliorant/seedling of 3 kg soil, equivalent to 0, 1, 2, 3, 4 and 5% (b/b of ameliorant respectively. Inorganic fertilizer was applied at 2 levels: 0 and 2 g fertilizer/application of N-P-K compound fertilizer of 15-15-15 respectively. The inorganic fertilizer was applied 4 times during nursery of coffee and cocoa. The result of the experiment indicated that coffee pulp may be used as natural soil ameliorant. Composition of ameliorant of 90% coffee pulp and 10% of minerals has good physical and chemical characteristics for soil amelioration. The composition has high water holding capacity; cations exchange capacity, organic carbon and phosphorus contents which are favorable to increase soil capacity to support plant growth. Application of

  15. Enzymatic hydrolysis of potato pulp

    OpenAIRE

    Mariusz Lesiecki; Wojciech Białas; Grażyna Lewandowicz

    2012-01-01

    Background. Potato pulp constitutes a complicated system of four types of polysaccharides: cellulose, hemicellulose, pectin and starch. Its composition makes it a potential and attractive raw material for the production of the second generation bioethanol. The aim of this research project was to assess the usefulness of commercial enzymatic preparations for the hydrolysis of potato pulp and to evaluate the effectiveness of hydrolysates obtained in this way as raw materials for ethanol ferment...

  16. Pectic substances from sugar beet pulp: structural features, enzymatic modification, and gel formation.

    OpenAIRE

    Oosterveld, A.

    1997-01-01

    Pectic substances are present in high proportions in sugar beet pulp. This by-product is therefore a potential raw material for the pectin industry. However, sugar beet pectin has poor physico-chemical properties compared with pectins from other sources. In order to improve these properties, pectins obtained from beet pulp by autoclaving and acid extraction were chemically characterized and subjected to enzymatic modification and oxidative cross-linking.The autoclave extracts contained two po...

  17. Electron treatment of wood pulp for the viscose process

    International Nuclear Information System (INIS)

    Electron processing is currently being evaluated by several viscose producers for integration into their process. The viscose industry converts dissolving wood pulp into products such as staple fibre, filament, cord, film, packaging, and non-edible sausage casings. These materials are used in the clothing, drapery, hygiene, automobile, food, and packaging industries. Viscose producers are facing increasingly high production costs and stringent environmental regulations that have forced some plants to close. Electron treatment of wood pulp can significantly reduce the amounts of chemicals used for producing viscose and the production of hazardous pollutants. Acsion Industries has worked with companies worldwide to demonstrate the benefits of using electron treated pulp for producing viscose (rayon). This paper describes the viscose process, the benefits of using electron treatment in the viscose process, and Acsion's efforts in developing this technology. (author)

  18. Swedish Pulp Mill Biorefineries. A vision of future possibilities

    Energy Technology Data Exchange (ETDEWEB)

    Berntsson, Thore (Chamers Univ. of Technology, Goeteborg (Sweden)); Axegaard, Peter; Backlund, Birgit; Samuelsson, Aasa; Berglin, Niklas; Lindgren, Karin (STFI-Packforsk, Stockholm (Sweden))

    2008-07-01

    Today, modern science could make it possible to develop techniques for refining almost the whole wood-matter, pulp mill side streams and bark compounds into platform chemicals, electricity, high quality fuels and structured feed-stock for chemicals and materials. The major challenge is to convert the state of basic scientific knowledge into industrial practise. Our definition of an integrated biorefinery is: 'Full utilization of the incoming biomass and other raw materials for simultaneous and economically optimized production of fibres, chemicals and energy'. Examples of products from a pulp mill biorefinery are: Chemicals and Materials (Phenols, adhesives, carbon fibres, activated carbon, binders, barriers, adhesives, antioxidants, surfactants, chelants, solvents, adhesives surfactants, descaling agents, specialty polymers, pharmaceuticals, nutraceuticals, cosmetics etc., Biofuels (pellets, lignin fuel, methanol, DME, ethanol etc), Electricity (BLGCC, condensing power etc.). The new or increased amounts of traditional products can be made from internal and/or external biomass. Three different levels can be identified: A high degree of energy saving in future mills, especially chemical pulp mills, will lead to large amounts of excess internal biomass which can be transferred to products mentioned above, Components in e.g. the black liquor, forest residues and bark can be upgraded to more valuable ones and the energy balance of the mill is kept through fuel import, wholly or partly depending on the level of mill energy efficiency. This imported fuel can be biomass or other types. External (imported) biomass (in some cases together with excess internal biomass) can be upgraded using synergy effects of docking this upgrading to a pulp mill. Electricity has been included as one of the possible biorefinery products. The electricity production in a mill can be increased in several ways which cannot be directly considered as biorefineries, e.g. recovery boiler

  19. Avaliação física e química da polpa de maracujá congelada comercializada na região de Bauru Physical-chemical evaluation of the frozen passion fruit pulp traded in the Bauru region

    Directory of Open Access Journals (Sweden)

    Kátia Raimundo

    2009-06-01

    Full Text Available A indústria de polpa de maracujá tem como objetivo a obtenção de produtos com características sensoriais e nutricionais próximas da fruta in natura. O objetivo deste trabalho foi avaliar as informações nutricionais das embalagens e as características físico-químicas das polpas de maracujá congeladas. Foram analisadas 25 amostras, de 07 marcas diferentes, adquiridas em supermercados de Bauru-SP, e região. Apenas uma das marcas analisadas (14,3% encontra-se em acordo com a legislação vigente, sendo que as demais apresentam tabelas ultrapassadas ou incompletas. As características físico-químicas diferem entre as marcas comercializadas, principalmente quanto ao teor de ácido ascórbico, sendo que 64,0% das amostras se encontram em desarcordo com o Regulamento Técnico para Fixação dos Padrões de Identidade e Qualidade (PIQ para polpa de maracujá do Ministério da Agricultura. As variações observadas entre a polpa in natura e a congelada são menores nos itens: densidade, pH, sólidos solúveis totais, acidez em ácido cítrico e ratio, mas altas quanto ao teor de ácido ascórbico.The purpose of passion fruit pulp industry is to keep the taste and nutritional characteristics as close as possible to the natural fruit. The objective of this work was to evaluate the packing nutritional information and the physical-chemical characteristics of the frozen passion fruit pulp. It was analyzed 25 pulp samples of the 07 different brand names found in Bauru and nearby cities in the State of São Paulo. Just one of the analyzed brand names (14.3 % was according to the current Brazilian Food Legislation, the others had exceeded or incomplete tables. The variations of the physical-chemical characteristics for the traded brands were mainly due to the rate of ascorbic acid (vitamin C and 64% of the samples also don't follow the rules of the Technical Regulation for Identity and Quality Standards (PIQ for passion fruit pulp of the

  20. Composition, texture and methane potential of cellulosic residues from Lewis acids organosolv pulping of wheat straw.

    Science.gov (United States)

    Constant, Sandra; Barakat, Abdellatif; Robitzer, Mike; Di Renzo, Francesco; Dumas, Claire; Quignard, Françoise

    2016-09-01

    Cellulosic pulps have been successfully isolated from wheat straw through a Lewis acids organosolv treatment. The use of Lewis acids with different hardness produced pulps with different delignification degrees. The cellulosic residue was characterised by chemical composition, X-ray diffraction, FT-IR spectroscopy, N2 physisorption, scanning electron microscopy and potential for anaerobic digestibility. Surface area and pore volume increased with the hardness of the Lewis acid, in correspondence with the decrease of the amount of lignin and hemicellulose in the pulp. The non linearity of the correlation between porosity and composition suggests that an agglomeration of cellulose fibrils occurs in the early stages of pulping. All organosolv pulps presented a significantly higher methane potential than the parent straw. A methane evolution of 295Ncm(3)/g OM was reached by a moderate improvement of the accessibility of the native straw. PMID:27295251

  1. 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.

  2. THE EFFECT OF HEMICELLULOSE EXTRACTION ON FIBER CHARGE PROPERTIES AND RETENTION BEHAVIOR OF KRAFT PULP FIBERS

    Directory of Open Access Journals (Sweden)

    Katja Lyytikäinen

    2011-02-01

    Full Text Available The integrated forest biorefinery (IFBR concept provides a promising opportunity for the development of the pulp and paper industry. One proposed next generation technology for an integrated forest biorefinery is the extraction of hemicelluloses, allowing the co-production of pulp and different hemicellulose-based chemicals. In addition to paper properties, hemicelluloses are known to be important for the function of cationic papermaking additives, because they are the main source of charged groups in fibers. This paper shows that the alkaline extraction of hemicelluloses from bleached kraft pulp decreases both the total and surface charge of the pulps. It was found that the decreased fiber charge leads to increased filler retention with fixed retention aid dosage. The reduction observed in the fiber surface charge for alkali-extracted pulp was mainly attributed to the decrease in the amount of anionic groups located in fines.

  3. ALKALINE PEROXIDE MECHANICAL PULPING OF FAST GROWTH PAULOWNIA WOOD

    Directory of Open Access Journals (Sweden)

    Ahmad Jahan Latibari,

    2011-11-01

    Full Text Available Alkaline peroxide mechanical pulping of paulownia wood harvested from exotic tree plantations in northern Iran was investigated. The fiber length, width, and cell wall thickness of this wood were measured as 0.82 mm, 40.3 μm, and 7.1 μm, respectively. The chemical composition including cellulose, lignin, and extractives soluble in ethanol-acetone, 1% NaOH, hot and cold water was determined as 49.5%, 25%, 12.1%, 26.9%, 11.4%, and 8.1% respectively. The ash content of this wood was 0.45%. Pre-washed chips were chemically treated at 70°C for 120 minutes with different combinations of three dosages (1.5, 3, and 4.5% of hydrogen peroxide and three dosages (1.5, 3, and 4.5% of sodium hydroxide prior to defibration. Other chemicals including DTPA, sodium silicate, and MgSO4 were constant at 0.5%, 3%, and 0.5%, respectively. The results showed that using a 1.5% hydrogen peroxide and 4.5% sodium hydroxide charge, the brightness of APMP pulp reached 68.7% ISO and higher chemical dosages did not improve the brightness; however, to produce APMP pulp with higher strength, a sodium hydroxide charge of 4.5% was needed. The tensile strength, tear strength, burst strength indices, and bulk density of the APMP pulp produced from 1.5% hydrogen peroxide and 4.5% sodium hydroxide were measured as 15.5Nm/g, 6.54mN.m2/g, 0.56kPa.m2/g, and 3.47cm3/g, respectively. The resulting pulp was bulky and is suitable for use in the middle layer of boxboard to provide the desired stiffness with a lower basis weight.

  4. Soda-anthraquinone pulping of palm oil empty fruit bunches and beating of the resulting pulp.

    Science.gov (United States)

    Jiménez, L; Serrano, L; Rodríguez, A; Sánchez, R

    2009-02-01

    The influence of soda-anthraquinone pulping variables (temperature, time and soda concentration) and beating (number of PFI beating revolution) of palm oil empty fruit bunches (EFB) on the resulting paper sheets was studied, with a view to identifying the optimum operating conditions. Equations were derived that reproduced the properties of the paper sheets with errors less than 10-12% in 90-95% of cases. An optimum compromise was found as regards operating conditions (15% soda, 170 degrees C, 70 min and 2400 number of PFI beating revolutions) that provided paper properties departing by less than 12% from their optimum values (59.63 Nm/g tensile index, 4.48% stretch, 4.17 kN/g burst index and 7.20 m Nm(2)/g tear index), and a beating grade of 47.5 degrees SR, acceptable to obtain paper sheets. Because these conditions involve a lower soda, temperature, time and beating than those required to maximize the studied paper properties, they can save chemical reagents, energy and immobilized capital for industrial facilities. On the other hand, the stretch properties of these pulp beaten are higher than those of others non-wood pulps, as wheat straw and olive wood. PMID:18815028

  5. Grafted wood pulp containing quaternary ammonium group and its application in the removal of different anions from aqueous solution

    International Nuclear Information System (INIS)

    Network wood pulp based on acrylonitrile has been chemically modified through different reactions to obtain group capable of anion exchange. Graft copolymerization of acrylonitrile onto wood pulp was carried out by using gamma-radiation 60Co. Factors affecting the grafting process e.g radiation dose and monomer concentration were investigated.The chemical modification of cyano groups were carried out by reaction with ethanol amine producing oxazoline group followed by quaternization of tertiary amine by reaction with benzyl chloride producing quaternary ammonium salt. The grafted and modified wood pulp were characterized by FTIR, SEM and TGA.Qualitative experiments of adsorption were conducted to evaluate the modified wood pulp on fixing sulfate, phosphate,nitrate and dichromate from aqueous solution using batch extractions. Based on the results obtained, it may be concluded that it is possible to modify chemically wood pulp containing cyano groups by different routes for its usage as anion exchanger

  6. SIMULATION AND OPTIMIZATION OF TIMBER ALKALINE PULPING PROCESS IN PRESENCE OF SALTS OF SOME METALS HAVING MIXED VALENCE

    OpenAIRE

    I. Karpunin

    2012-01-01

    Process of alkaline pulping in the presence of salts of some metals having mixed valence has been simulated on the basis of the executed investigations. The paper reveals that optimization of alkaline (sulphate) pulping depends on chemical nature and metal and its amount which is introduced in the form of salt.

  7. SIMULATION AND OPTIMIZATION OF TIMBER ALKALINE PULPING PROCESS IN PRESENCE OF SALTS OF SOME METALS HAVING MIXED VALENCE

    Directory of Open Access Journals (Sweden)

    I. Karpunin

    2012-01-01

    Full Text Available Process of alkaline pulping in the presence of salts of some metals having mixed valence has been simulated on the basis of the executed investigations. The paper reveals that optimization of alkaline (sulphate pulping depends on chemical nature and metal and its amount which is introduced in the form of salt.

  8. Electron beam processing technology for modification of different types of cellulose pulps for production of derivatives

    International Nuclear Information System (INIS)

    Institute of Nuclear Chemistry and Technology, Pulp and Paper Research Institute and Institute of Chemical Fibers carry out a joint research project in order to develop the radiation methods modification of cellulose pulps for production of cellulose derivatives such as carbamate (CC), carboxymethyl cellulose (CMC) and methylcellulose (MC). Three different types of textile pulps: Alicell (A); Borregaard (B), Ketchikan (K) and Kraft softwood (PSS) and hardwood (PSB) pulps have been irradiated with 10 MeV electron beam from LAE 13/9 linear accelerator with doses of 5, 10, 15, 20, 25 and 50 kGy. After electron beam treatment the samples of cellulose pulps have been examined by using of structural and physico-chemical methods. Electron paramagnetic resonance spectroscopy (EPR), gel permeation chromatography (GPC) and infrared spectroscopy (IRS) were applied for determination of structural changes in irradiated cellulose pulps. By means of analytical methods, such parameters as: viscosity, average degree of polymerization (DP) and α-cellulose contents were evaluated. Based on EPR and GPC investigations the relationship between concentrations of free radicals and decreasing polymerization degrees in electron beam treatment pulps has been confirmed. The carboxymethylcellulose, methylcellulose and cellulose carbamate were prepared using the raw material of radiation modified pulps. Positive results of investigations will allow for determination of optimum conditions for electron beam modification of selected cellulose paper and textile pulps. Such procedure leads to limit the amounts of chemical activators used in methods for preparation cellulose derivatives. The proposed electron beam technology is new approaches in technical solution and economic of process of cellulose derivatives preparation. (author)

  9. Enzymatic hydrolysis of potato pulp

    Directory of Open Access Journals (Sweden)

    Mariusz Lesiecki

    2012-03-01

    Full Text Available Background. Potato pulp constitutes a complicated system of four types of polysaccharides: cellulose, hemicellulose, pectin and starch. Its composition makes it a potential and attractive raw material for the production of the second generation bioethanol. The aim of this research project was to assess the usefulness of commercial enzymatic preparations for the hydrolysis of potato pulp and to evaluate the effectiveness of hydrolysates obtained in this way as raw materials for ethanol fermentation. Material  and methods. Sterilised potato pulp was subjected to hydrolysis with commercial enzymatic preparations. The effectiveness of the preparations declared as active towards only one fraction of potato pulp (separate amylase, pectinase and cellulase activity and mixtures of these preparations was analysed. The monomers content in hydrolysates was determined using HPLC method. Results.  The application of amylolytic enzymes for potato pulp hydrolysis resulted in the release of only 18% of raw material with glucose as the dominant (77% constituent of the formed product. In addition, 16% galactose was also determined in it. The hydrolysis of the cellulose fraction yielded up to 35% raw material and the main constituents of the obtained hydrolysate were glucose (46% and arabinose (40%. Simultaneous application of amylolytic, cellulolytic and pectinolytic enzymes turned out to be the most effective way of carrying out the process as its efficiency in this case reached 90%. The obtained hydrolysate contained 63% glucose, 25% arabinose and 12% other simple substances. Conclusion. The application of commercial enzymatic preparations made it possible to perform potato pulp hydrolysis with 90% effectiveness. This was achieved by the application of a complex of amylolytic, cellulolytic and pectinolytic enzymes and the hydrolysate obtained in this way contained, primarily, glucose making it a viable substrate for ethanol fermentation.

  10. Fermentation profile, chemical composition and dry matter losses of orange pulp silage with different microbial inoculantsPerfil fermentativo, composição bromatológica e perdas em silagem de bagaço de laranja com diferentes inoculantes microbianos

    Directory of Open Access Journals (Sweden)

    Mônica Chaves Françozo

    2012-02-01

    Full Text Available The objective of this experiment was to evaluate the effects of microbial inoculants on the reduced concentration of gases and effluent, dry matter recovery, pH, volatile fatty acids, and chemical composition of orange pulp silage, using a completely randomized design, with four treatments and four replicates per treatment. The treatments were: orange pulp silage (CONT, citrus pulp silage + Lactobacillus plantarum (LAC, citrus pulp silage + Lactobacillus buchneri (BUCH, citrus pulp silage + Lactobacillus plantarum and buchneri (LACBUCH. Inoculants were applied at a rate of 25 liters of solution per ton of citrus pulp containing 1x103 CFU respectively of Lactobacillus plantarum and Lactobacillus buchneri per gram of silage. There was no effect of the usage of different inoculants on the reduction of gas and effluent, as well as the pH of the silage. The dry matter (DM, crude protein (CP, non-fibrous carbohydrate (NFC, mineral matter (MM, ether extract (EE and the profile of fatty acids did not change significantly with the inclusion of the inoculants. The contents of neutral detergent fiber (NDF and acid detergent fiber (ADF were higher for silage with Lactobacillus buchneri compared to control. The administration of microbial inoculants in orange pulp silage did not result in benefits relative to the dry matter losses during ensiling or the nutritional components. Objetivou-se com este experimento avaliar os efeitos de inoculantes microbianos sobre as perdas por gases e efluentes, recuperação de matéria seca, pH, ácidos graxos voláteis e composição bromatológica de silagens de polpa cítrica, usando-se um delineamento inteiramente casualizado, com quatro tratamentos e quatro repetições. Os tratamentos foram: silagem de polpa cítrica (CONT, silagem de polpa cítrica + Lactobacillus plantarum (LAC, silagem de polpa cítrica + Lactobacillus buchneri (BUCH; silagem de polpa cítrica + Lactobacillus plantarum e buchneri (LACBUCH. Os

  11. The role of anthraquinone in neutral sulphite pulping of wood chips

    OpenAIRE

    Vuorinen, Sakari

    2015-01-01

    The aim of this thesis was to investigate the carcinogenic potential of anthraquinone (AQ) and verify the new proposed working mechanism of AQ in neutral sulphite pulping by using six different quinones with varying redox potentials. The idea behind the new working mechanism was to investigate whether additives with lower redox potential could be better antioxidants and thus more effective pulping chemicals. In addition, the much discussed AQ reaction mechanisms as well as the synergism of po...

  12. Pulping characteristics of Eucalyptus species grown in Malawi (ODNRI Bulletin No. 33)

    OpenAIRE

    Palmer, E. R.; Gibbs, J A; Ganguli, S; Dutta, A.P.

    1989-01-01

    Eight species of Eucalyptus, E. camaldulensis, E. citriodora, E. cloeziana, E. grandis, E. maculata, E. maidenii, E. saligna and F. tereticornis grown in the Viphya plateau, Malawi, were examined to determine their suitability for the production of papermaking pulp. The size of 9-year-old trees, wood density, chemical characteristics and fibre dimensions are reported. All species were pulped by sulphate, soda and soda-anthraquinone processes. By the sulphate process all species yielded over 4...

  13. Surface modification of cellulose materials : from wood pulps to artificial blood vessels

    OpenAIRE

    Ahrenstedt, Lage

    2007-01-01

    This thesis describes the improvement of two radically different cellulose materials, paper and artificial blood vessels, constructed from two diverse cellulose sources, wood pulp and Acetobacter xylinum. The improvement of both materials was possible due to the natural affinity of the hemicellulose xyloglucan for cellulose. Chemical and mechanical pulps were treated with xyloglucan in the wet-end prior to hand sheet formation or by spray application of dry hand sheets, loading a comparable a...

  14. INTEGRATION OF KRAFT PULPING ON A FOREST BIOREFINERY BY THE ADDITION OF A STEAM EXPLOSION PRETREATMENT

    OpenAIRE

    Raquel Martin-Sampedro; Maria E. Eugenio; Esteban Revilla; Juan A. Martin; J. Carlos Villar

    2011-01-01

    Steam explosion has been proposed for a wide range of lignocellulosic applications, including fractionation of biomass, pre-treatment of biomass for ethanol production, or as an alternative to conventional mechanical pulping. Nevertheless, a steam explosion process could also be used as pretreatment before chemical pulping, expecting a reduction in cooking time due to the open structure of the exploded chips. Thus, to evaluate the effect of steam explosion as a pretreatment in the kraft pulpi...

  15. Caracterização físico-química de polpas de frutos da Amazônia e sua correlação com a atividade anti-radical livre Physical and chemical characterization of fruit pulps from Amazonia and their correlation to free radical scavenger activity

    Directory of Open Access Journals (Sweden)

    Gisele André Baptista Canuto

    2010-12-01

    Full Text Available Características físico-químicas (cor, pH, acidez total titulável, sólidos solúveis totais, conteúdo de lipídios e umidade e níveis de compostos bioativos (ácido ascórbico, fenólicos totais foram determinados em quinze amostras de polpas de frutos procedentes da região Amazônica (abiu, acerola, açaí, araçá-boi, bacaba, bacuri, buriti, cajá, cajarana, caju, cupuaçu, graviola, murici, noni e tamarindo. A atividade de radicais livres foi avaliada pelo método de ABTS. Algumas polpas apresentaram alta potencialidade antioxidante, associada com a atividade antirradicais livres obtida e os conteúdos dos componentes bioativos como compostos fenólicos e ácido ascórbico, destacando-se acerola e acaí. O conteúdo total de compostos fenólicos foi correlacionado à capacidade antioxidante das polpas.Physical and chemical characteristics (color, pH, titratable acidity, total soluble solids, lipid content, moisture and levels of bioactive compounds (ascorbic acid, total phenolics were determined in fifteen samples of fruit pulps from Amazonia (abiu, acerola, açaí, araça-boi, bacaba, bacuri, buriti, cajá, cajarana, caju, cupuaçu, graviola, murici, noni e tamarindo. The free radical scavenger activity was evaluated by the ABTS assay. Some pulps presented high antioxidant potential, associated with the free radical scavenger activity measured and the content of bioactive components, such as phenolic compounds and ascorbic acid, especialy in acerola and açaí. The total phenolic content was correlated to antioxidant capacity of pulps.

  16. 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%). PMID:18226892

  17. Quality of wood and pulp from a clone of Eucalyptus grandis planted at three locations

    Directory of Open Access Journals (Sweden)

    Cláudio Angeli Sansígolo

    Full Text Available Eucalyptus grandis is one of the most popular species to use as raw material for pulp production in Brazil, as it provides excellent pulping, bleaching and papermaking results. The main objective of this study is to examine the quality of wood and pulp from a clone of Eucalyptus grandis, at age 4 years approximately, planted in three different soils, two of which being low fertility and one being a superior fertility soil, and their reflections on wood quality and pulping results. Chemical analyses of the soils followed guidelines developed by Raij et al. (2001, while physical and chemical properties of the wood followed ABTCP, TAPPI and ABNT standards. Chemical analyses of the soils pointed to lower fertility in Fazenda Limeira and Fazenda Tapera Queimada as opposed to higher fertility in Fazenda Mendes União. Results revealed stronger tendencies for the stand grown in the less fertile soils (Fazenda Limeira and Fazenda Tapera Queimada in comparison to the stand grown in more fertile soil (Fazenda Mendes União as to: higher wood and bark basic density, lower height and dry matter content, higher bark content, lower extractives content and higher holocellulose content, higher total and screened yields from pulping, lower specific wood consumption/t of pulp, and higher tear and tensile indices at low refining levels.

  18. Pulp Regeneration: Current Approaches and Future Challenges

    Science.gov (United States)

    Yang, Jingwen; Yuan, Guohua; Chen, Zhi

    2016-01-01

    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. PMID:27014076

  19. Effects of the bleaching sequence on the optical brighteners action in eucalyptus kraft pulp

    Directory of Open Access Journals (Sweden)

    Mauro Manfredi

    2014-06-01

    Full Text Available During the bleaching process the pulp is treated with chemical reagents that can be retained in the pulp and interfere in the action of the optical brighteners. Different bleaching sequences can produce pulps at the same brightness but with different potential to whiteness increase when treated with optical brighteners. The objective of this study was to evaluate the influence of the bleaching sequence on the efficiency of disulphonated and tetrasulphonated optical brighteners. Eucalyptus kraft pulp was bleached using four different bleaching sequences. For each pulp three brightness targets were aimeds. For each bleaching sequence mathematical model was generated for predicting the final pulp whiteness according to the initial brightness and the optical brightener charge applied. The presence of organochlorine residues in the pulp reduced the effectiveness of the optical brighteners. Therefore, bleaching sequences that use low chlorine dioxide charge favors for greater gains in whiteness with the application of optical brighteners. The replacement of the final chlorine dioxide bleaching stage with a hydrogen peroxide one in the sequence increased the efficiency of the optical brightening agents.

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

    International Nuclear Information System (INIS)

    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 107R, but there was a slight deterioration up to 106R. (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)

  1. Microfibrillated cellulose from bamboo pulp and its properties

    International Nuclear Information System (INIS)

    Microfibrillated cellulose (MFC) was obtained by disintegrating bleached kraft bamboo (Phyllostachys pubescens) pulp with a procedure of chemical pretreatment and high-pressure homogenization. The influences of sodium hydroxide dosage and homogenization times were evaluated by water retention value (WRV) of MFC. The properties, such as the surface morphology, rheological property and carboxyl acid content of MFC were also characterized using scanning electron microscope (SEM), rheometer and headspace gas chromatography (HS-GC) separately.

  2. Effect of physical and chemical factors on Macaca Mulatta′s pulp and change of the collagen in pulp%理化因素刺激对牙髓及其胶原 影响的实验研究

    Institute of Scientific and Technical Information of China (English)

    袁理; 岳林; 毛秀萍; 高岩

    2001-01-01

    Objective To investigate the change of pulp and its collagen to outside stimuli. Methods 51 permanent teeth from 10 adult healthy Macaca Mulatta′s monkeys were chosen as experimental teeth. 39 of them were prepared Class V cavities. The teeth were divided into two groups, one was filled with zinc phosphate cement and another group with zinc oxide eugenol. A blank control group of 12 teeth was set at the same time. Just after the operation, 3 d, 7 d, 1 month and 3 months later, the animals were executed. Histologic changes were evaluated by means of HE and collagen staining method. Results Local inflammation was the major representation in the pulps of the zinc phosphate cement group from 7d to 3 months after operation. The percentage of collagen decrease dropped sharply,and there was no inflammation cells infiltration in the pulps of zinc oxide eugenol group from 1 to 3 months after operation. By means of collagen staining method, the morphological characters ,distribution and the change of pulpal collagen during a certain pathologic process were clearly represented in histologic slices. The change of collagen appeared earlier than the inflammation cells infiltration. Conclusions Zinc phosphate cement can lead to medium inflammation of the pulp. The change of collagen appears earlier than that of WBC, which can be used as a sensitive indicator.%目的了解猴牙髓及其胶原对物理、化学刺激的反应。方法观察磷酸锌粘固剂及氧化锌丁香油酚粘固剂(zinc oxide eugenol,ZOE)间接盖髓后,恒河猴牙髓即刻、3 d、7 d、1个月、3个月HE和胶原特殊染色后的组织学变化。结果①磷酸锌粘固剂组术后7 d~3个月,牙髓以局限性炎症损伤为主;②ZOE组术后1~3个月胶原减少明显下降,已无炎症细胞浸润;③胶原特殊染色法可清楚地反映牙髓胶原的形态特点、分布及变化,术后3 d胶原明显减少早于炎症细胞的出现。结论磷酸锌粘固剂对

  3. Perfil de ácidos graxos e composição química do músculo longissimus dorsi de cordeiros alimentados com dietas contendo polpa cítrica Fatty acids profile and chemical composition of longissimus muscle of lambs fed citrus pulp

    Directory of Open Access Journals (Sweden)

    Gustavo Henrique Rodrigues

    2010-06-01

    Full Text Available Objetivou-se com este trabalho avaliar os efeitos da substituição do milho por polpa cítrica na composição química e no perfil de ácidos graxos do músculo longissimus dorsi de cordeiros. Utilizaram-se 32 cordeiros Santa Inês não-castrados abatidos aos 141 dias de idade com peso médio de 33 kg. Os cordeiros foram alimentados com ração contendo 90% de concentrado (milho moído e/ou polpa cítrica, farelo de soja e minerais e 10% de feno de "coastcross" (Cynodon spp. A polpa cítrica foi adicionada nos níveis de 23,7; 46,1; e 68,4% da matéria seca em substituição a 33, 67 e 100% do milho, respectivamente. A substituição total do milho pela polpa cítrica promoveu aumento de 177% na concentração de ácido linolênico (C18:3, enquanto a substituição parcial resultou em aumento de 72% no ácido linoleico conjugado (C18:2 cis-9 trans-11. Não houve alteração na concentração total de ácidos graxos saturados, monoinsaturados e poliinsaturados. Entretanto, a quantidade de gordura intramuscular do longissimus dorsi diminuiu com o aumento de polpa cítrica na ração, sem alterar os teores de umidade, proteína e cinzas. A substituição do milho por polpa cítrica na ração modifica a quantidade e o perfil de lipídios do músculo longissimus dorsi de cordeiros.The objective of this study was to determine the effects of replacing corn by dried citrus pulp on chemical composition and fatty acids profile in longissimus dorsi muscle of thirty-two Santa Ines lambs, slaughtered at average weight of 33 kg at 141 days of age. Lambs were fed a 90% concentrate (ground corn and/or dried citrus pulp, soybean meal and minerals and 10% coastcross hay (Cynodon spp diet. Dried citrus pulp was added at 23.7, 46.1 and 68.4% of dry matter replacing corn by 33, 67 and 100%, respectively. Total replacement of corn by dried citrus pulp resulted in 177% increase in linolenic acid concetration (C18:3 while a partial replacement showed 72% increase in

  4. Physicochemical characteristics of commercial umbu pulp (Spondias tuberosa Arruda Câmara: concentration effect

    Directory of Open Access Journals (Sweden)

    Jaqueline Santos Bastos

    2016-03-01

    Full Text Available The umbu is the umbuzeiro fruit (Spondias tuberosa Arr. Cam. which is a tree native of the Brazilian backlands. The aim of this work was to evaluate the physical and chemical properties of commercial and concentrated umbu pulp to be used as raw material in the production of structured. The commercial pulp (2.5 kg was acquired in the trade of Feira de Santana. The concentration of the evaporator route pulp vacuo to increase the soluble solids content of 8.5ºBrix to 15.5ºBrix It was held in the Food Chemistry Laboratory of the State University of Feira de Santana. It was obtained after concentrating a yield of 41.12% by mass of fruit pulp. The concentration process had no influence in the nutritional value of umbu pulp. The concentrated pulp had the following properties pH (2.43, soluble solids (15.5°Brix, acidity (3.11 g citric acid/100 g, total protein (1.28% - w/v, vitamin C (4.36 mg/100 g - w/v, reducing sugars (6.08% - w/v, total sugars (13.55% - w/v non reducing sugars (7.46% - w/v and ash (0.42% - w/v. The physicochemical characteristics of commercial umbu pulps had similar pH, Total Soluble Solids, acidity, proteins and ashes; higher values of reducing sugars and non-reducing and a lower vitamin C content that the pulps reported in the literature. The concentration process produced an increase in Total Soluble Solids, proteins, acidity, reducing and non reducing sugars and ash content. However there was a decrease in vitamin C concentration of the pulp.

  5. Pulping performance of transgenic poplar with depressed Caffeoyl-CoA O-methyltransferase

    Institute of Scientific and Technical Information of China (English)

    WEI JianHua; WANG YanZhen; WANG HongZhi; LI RuiFen; LIN Nan; MA RongCai; QU LeQing; SONG YanRu

    2008-01-01

    This paper evaluated pulping performance of 3-year-old field-grown transgenic poplar (Populus tremula × Populus alba). The transgenic poplar with anti-sense CCoAOMT had an about 13% decreased lignin content, in which a slight increment was found in S/G ratio. Chemical analysis showed that the trans-genic poplar had significantly less benezene-ethanol extractive than that of control wood, but no sig-nificant differences were found in contents of ash, cold water extractive, hot water extractive, 1% NaOH extractive, holocellulose, pentosans and cellulose. Fiber assay demonstrated that down-regulation of CCoAOMTexpression improved the fiber quality in transgenic poplar. Kraft pulping showed that lower lignin in transgenic poplar led to remarkable improved pulp quality and increased pulp yield.

  6. Anaerobic treatment of pulp and paper mill effluents--status quo and new developments.

    Science.gov (United States)

    Habets, Leo; Driessen, Willie

    2007-01-01

    Since the early 1980s, anaerobic treatment of industrial effluents has found widespread application in the pulp and paper industry. Over 200 installations are treating a large variety of different pulp and paper mill effluents. Amongst various anaerobic systems the UASB and IC are the most applied anaerobic reactor systems. Anaerobic treatment is well feasible for effluents originated from recycle paper mills, mechanical pulping (peroxide bleached), semi-chemical pulping and sulphite and kraft evaporator condensates. The advantages of anaerobic pre-treatment are (1) net production of renewable energy (biogas), (2) minimized bio-solids production, (3) minimal footprint and (4) reduced emission of greenhouse gases. Via in-line application of anaerobic treatment in closed circuits (paper kidney technology) further savings on cost of fresh water intake and effluent discharge levies are generated. PMID:17486855

  7. [Functional morphology of pulp tissue].

    Science.gov (United States)

    Heine, H; Schaeg, G; Türk, R

    1989-01-01

    As compared with mesenchyme no genuine defense cells are developed in the tissue of the dental pulp and the nervous tissue. This is a further hint for the common development from ectoderm. The three dimensional meshwork of pulpa fibroblasts ("mesectoderm") is structured by elongated cell processes connected with each other by a variety of special cell junctions ("electronic cell coupling"). Metabolites from the microcirculation and neuropeptides from vegetative axons influence the activity of fibroblasts synthetizing groundsubstance. The meshwork of the groundsubstance has exclusion effects concerning molecules with a distinct molecular weight and charge. Thus a primitive defense system is established. With this the role of a newly described cell type of the dental pulp, the "lymphocytic pericyte" is discussed. Because of the poor capacity of the pulpa tissue for immunological reactions pathologically disorders may easily become chronically spreading their antigenic components throughout the body. PMID:2800671

  8. Caracterização física e química dos frutos da umbu-cajazeira (Spondias spp em cinco estádios de maturação, da polpa congelada e néctar Physical and chemical characterization on the fruits of umbu-cajazeira (Spondias spp in five ripening stages, frozen pulp and nectar

    Directory of Open Access Journals (Sweden)

    ELIZA DOROTEA POZZOBON DE ALBUQUERQUE LIMA

    2002-08-01

    Full Text Available A umbu-cajazeira, no Brasil, apresenta boas potencialidades de cultivo e perspectivas de comercialização, o que objetivou este trabalho de avaliação da qualidade física e química dos frutos em cinco estádios de maturação classificados de acordo com o grau de cor da casca descritos como: fruto totalmente verde (1FTV, frutos com início de pigmentação (2FIP, frutos parcialmente amarelos (3FPA, frutos totalmente amarelos (4FTA, frutos totalmente amarelo-alaranjados (5FTAA, da polpa congelada e do néctar. As variáveis estudadas foram os atributos físicos: peso, diâmetro longitudinal, diâmetro transversal e rendimento em polpa, e químicos: vitamina C, acidez total titulável sólidos solúveis totais, pH e a relação sólidos solúveis totais/acidez total titulável. Os frutos, no estádio de maturação comercial (4FTA, apresentaram os seguintes valores mé ;dio: rendimento de polpa de 55,75%; pH de 2,08; SST de 11,25 °Brix; ATT de 1,77 g de ácido citrico/100g de polpa; SST/ATT de 6,39 e teor de vitamina C total de 17,75 mg/100g. A polpa congelada e o néctar mantiveram-se em condições estáveis em relaç ;ão ao pH, SST, ATT e SST/ATT, durante 60 dias de armazenamento. Quanto ao teor de vitamina C total, a polpa congelada apresentou um decréscimo signi ficativo, o que não ocorreu com o néctar.In Brazil some tropical fruits present great potential for cultivation and perspective of commercialization, one of them is the "umbu-cajazeira". A research has been developed aiming to measure the physical and chemical quality of the frozen pulp and the nectar obtained from "umbu-cajazeira" fruits, which were classified in distinct maturation stages. The fruits were divided according to shell colour in five groups: fruit completely green (1FCG, fruit starting to change shell's colour (2FSCC, fruit partially yellow (3FPY, fruit totally yellow (4FTY, fruit totaly orange-like yellow. The variables analysed comprised the physical

  9. Enzymes improve ECF bleaching of pulp

    OpenAIRE

    Lachenal, D.; Bajpai, P. K.; S P Mishra; Sharma, N.; Anand, A; Bajpai, P.

    2006-01-01

    The delignification efficiency of different laccase enzymes was examined on the eucalyptus Kraft pulp. The laccase enzyme from Trametes versicolor showing the highest delignification efficiency was selected and used in the elemental chlorine-free bleaching sequence for improving the pulp bleachability. An appreciable reduction in chlorine dioxide consumption was also obtained. Further reduction in chlorine dioxide consumption was obtained when the same laccase treated pulp was subjected to an...

  10. PULP DEMAND IN THE INTERNATIONAL MARKET

    OpenAIRE

    Edmilson Santos Cruz; Antonio Donizette de Oliveira; José Roberto Soares Scolforo; José Luis Pereira de Rezende

    2003-01-01

    This study aimed at analyzing the international pulp market, taking into account themain exporting countries and importing regions, with the objective of estimating, for each market, theown-price and cross-price elasticity in relation to the demand of the pulp, differentiated for country oforigin. The model considers that imports are differentiated by origin; therefore they are not perfect substitutes. The demand from Europe, North America and the Rest of the World for the pulp from theUnited...

  11. Characterization of bio-oil obtained from fruit pulp pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Ozbay, Nurguel [Bozueyuek Vocational School, Bilecik University, Bozueyuek, Bilecik (Turkey); Apaydin-Varol, Esin; Burcu Uzun, Basak [Department of Chemical Engineering, Anadolu University, Eskisehir (Turkey); Eren Puetuen, Ayse [Department of Chemical Engineering, Anadolu University, Eskisehir (Turkey)], E-mail: aeputun@anadolu.edu.tr

    2008-08-15

    Apricot pulps was pyrolyzed in a fixed-bed reactor under different pyrolysis conditions to determine the role of final temperature, sweeping gas flow rate and steam velocity on the product yields and liquid product composition with a heating rate of 5 deg. C/min. Final temperature range studied was between 300 and 700 deg. C and the highest liquid product yield was obtained at 550 deg. C. Liquid product yield increased significantly under nitrogen and steam atmospheres. For the optimum conditions, pyrolysis of peach pulp was furthermore studied. Liquid products obtained under the most suitable conditions were characterized by FTIR and {sup 1}H-NMR. In addition, gas chromatography/mass spectrophotometer was achieved on all pyrolysis oils. Characterization showed that bio-oil could be a potential source for synthetic fuels and chemical feedstock.

  12. Characterization of bio-oil obtained from fruit pulp pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Oezbay, Nurguel [Bozueyuek Vocational School, Bilecik University, Bozueyuek, Bilecik (Turkey); Apaydin-Varol, Esin; Burcu Uzun, Basak; Eren Puetuen, Ayse [Department of Chemical Engineering, Anadolu University, Eskisehir (Turkey)

    2008-08-15

    Apricot pulps was pyrolyzed in a fixed-bed reactor under different pyrolysis conditions to determine the role of final temperature, sweeping gas flow rate and steam velocity on the product yields and liquid product composition with a heating rate of 5{sup o}C/min. Final temperature range studied was between 300 and 700{sup o}C and the highest liquid product yield was obtained at 550{sup o}C. Liquid product yield increased significantly under nitrogen and steam atmospheres. For the optimum conditions, pyrolysis of peach pulp was furthermore studied. Liquid products obtained under the most suitable conditions were characterized by FTIR and {sup 1}H-NMR. In addition, gas chromatography/mass spectrophotometer was achieved on all pyrolysis oils. Characterization showed that bio-oil could be a potential source for synthetic fuels and chemical feedstock. (author)

  13. Characterization of bio-oil obtained from fruit pulp pyrolysis

    International Nuclear Information System (INIS)

    Apricot pulps was pyrolyzed in a fixed-bed reactor under different pyrolysis conditions to determine the role of final temperature, sweeping gas flow rate and steam velocity on the product yields and liquid product composition with a heating rate of 5 deg. C/min. Final temperature range studied was between 300 and 700 deg. C and the highest liquid product yield was obtained at 550 deg. C. Liquid product yield increased significantly under nitrogen and steam atmospheres. For the optimum conditions, pyrolysis of peach pulp was furthermore studied. Liquid products obtained under the most suitable conditions were characterized by FTIR and 1H-NMR. In addition, gas chromatography/mass spectrophotometer was achieved on all pyrolysis oils. Characterization showed that bio-oil could be a potential source for synthetic fuels and chemical feedstock

  14. In vitro penetration of bleaching agents into the pulp chamber

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Valera, M C; Mancini, M N G;

    2004-01-01

    To investigate pulp chamber penetration of bleaching agents in teeth following restorative procedures.......To investigate pulp chamber penetration of bleaching agents in teeth following restorative procedures....

  15. Chemical and functional characterization of seed, pulp and skin powder from chilto (Solanum betaceum), an Argentine native fruit. Phenolic fractions affect key enzymes involved in metabolic syndrome and oxidative stress.

    Science.gov (United States)

    Orqueda, María Eugenia; Rivas, Marisa; Zampini, Iris Catiana; Alberto, María Rosa; Torres, Sebastian; Cuello, Soledad; Sayago, Jorge; Thomas-Valdes, Samanta; Jiménez-Aspee, Felipe; Schmeda-Hirschmann, Guillermo; Isla, María Inés

    2017-02-01

    The aim of this work was to assess the nutritional and functional components of powder obtained by lyophilization of whole fruits, seeds, pulp and skin from chilto (Solanum betaceum Cav) cultivated in the ecoregion of Yungas, Argentina. The powders have low carbohydrate and sodium content and are a source of vitamin C, carotenoid, phenolics, potassium and fiber. The HPLC-ESI-MS/MS analysis of the fractions enriched in phenolics allowed the identification of 12 caffeic acid derivatives and related phenolics, 10 rosmarinic acid derivatives and 7 flavonoids. The polyphenols enriched extracts before and after simulated gastroduodenal digestion inhibited enzymes associated with metabolic syndrome, including α-glucosidase, amylase and lipase and exhibited antioxidant activity by different mechanisms. None of the analyzed fruit powders showed acute toxicity or genotoxicity. The powders from the three parts of S. betaceum fruit may be a potential functional food and the polyphenol enriched extract of seed and skin may have nutraceutical properties. PMID:27596394

  16. Microscopic analysis of dog dental pulp after pulpotomy and pulp protection with mineral trioxide aggregate and white Portland cement Análise microscópica da polpa dental de cães após pulpotomia e proteção pulpar com agregado de trióxido mineral e cimento Portland branco

    OpenAIRE

    Renato Menezes; Clóvis Monteiro Bramante; Roberto Brandão Garcia; Ariadne Letra; Vanessa Graciela Gomes Carvalho; Everdan Carneiro; Sérgio Brunini; Rodrigo Cardoso de Oliveira; Giovana Calichio Canova; Fernanda Gomes de Moraes

    2004-01-01

    Considering previous studies on the similarity between the chemical composition of the mineral trioxide aggregate and the Portland cement, the purpose of this study was to investigate the pulp response of dog's teeth after pulpotomy and direct pulp protection with MTA Angelus and white Portland cement. Thirty eight pulp remnants were protected with these materials. One hundred and twenty days after treatment, the animals were sacrificed and the specimens removed and prepared for histological ...

  17. Modification in the properties of paper by using cellulase-free xylanase produced from alkalophilic Cellulosimicrobium cellulans CKMX1 in biobleaching of wheat straw pulp.

    Science.gov (United States)

    Walia, Abhishek; Mehta, Preeti; Guleria, Shiwani; Shirkot, Chand Karan

    2015-09-01

    Alkalophilic Cellulosimicrobium cellulans CKMX1 isolated from mushroom compost is an actinomycete that produces industrially important and environmentally safer thermostable cellulase-free xylanase, which is used in the pulp and paper industry as an alternative to the use of toxic chlorinated compounds. Strain CKMX1 was previously characterized by metabolic fingerprinting, whole-cell fatty acids methyl ester analysis, and 16S rDNA and was found to be C. cellulans CKMX1. Crude enzyme (1027.65 U/g DBP) produced by C. cellulans CKMX1, having pH and temperature optima of 8.0 and 60 °C, respectively, in solid state fermentation of apple pomace, was used in the production of bleached wheat straw pulp. Pretreatment with xylanase at a dose of 5 U/g after pulping decreased pulp kappa points by 1.4 as compared with the control. Prebleaching with a xylanase dose of 5 U/g pulp reduced the chlorine charge by 12.5%, increased the final brightness points by approximately 1.42% ISO, and improved the pulp strength properties. Xylanase could be substituted for alkali extraction in C-Ep-D sequence and used for treating chemically bleached pulp, resulting in bleached pulp with higher strength properties. Modification of bleached pulp with 5 U of enzyme/g increased pulp whiteness and breaking length by 1.03% and 60 m, respectively; decreased tear factor of pulp by 7.29%; increased bulk weight by 3.99%, as compared with the original pulp. Reducing sugars and UV-absorbing lignin-derived compound values were considerably higher in xylanase-treated samples. Cellulosimicrobium cellulans CKMX1 has a potential application in the pulp and paper industries. PMID:26220821

  18. EVALUATION OF A NEW LACCASE PRODUCED BY STREPTOMYCES IPOMOEA ON BIOBLEACHING AND AGEING OF KRAFT PULPS

    Directory of Open Access Journals (Sweden)

    M. Enriqueta Arias

    2011-06-01

    Full Text Available The aim of this work is to prove the suitability of a new alkaline and halo-tolerant bacterial laccase (SilA produced by Streptomyces ipomoea CECT 3341 to enhance the conventional chemical bleaching process of an industrial eucalyptus kraft pulp. The laccase used for this study was a recombinant laccase obtained from cultures of E. coli BL21 (DE3 grown in LB liquid medium. The biobleaching experiment was carried out on Eucalyptus globulus kraft pulps using the above mentioned laccase and acetosyringone as natural mediator. Then, an alkaline extraction and further hydrogen peroxide steps were applied to evaluate the efficiency of the laccase-mediator system as a pretreatment in the bleaching sequences. Biobleached pulps showed a kappa number decrease and a brightness increase without decreasing the viscosity values significantly. Also, a reduction in the consumption of hydrogen peroxide was observed when the enzymatic treatment was applied to the pulp. CIE L*a*b* and CIE L*C* color coordinates measured in pulps demonstrated that among all treatments applied to pulps, the laccase-acetosyringone system presented the best optical properties even after an accelerated ageing process. Finally, it is also remarkable that during this treatment 64% of the laccase activity remained unaltered.

  19. MODELING HYDROGEN PEROXIDE BLEACHING OF SODA PULP FROM OIL-PALM EMPTY FRUIT BUNCHES

    Directory of Open Access Journals (Sweden)

    Ana Ferrer

    2011-04-01

    Full Text Available The influence of the variables soda (0.5-3.0%, hydrogen peroxide (1.0-6.0% and time (1-5 h in the bleaching of soda pulp of empty fruit bunches (EFB from oil-palm, on the properties of bleached pulps, was studied. Polynomial and neural fuzzy models reproduced the results of brightness, kappa number, and viscosity of the pulps with errors less than 10%. By the simulation of the bleaching of pulp, using the polynomial and neural fuzzy models, it was possible to find optimal values of operating variables, so that the properties of bleached pulps differed only slightly from their best values and yet it was possible to save chemical reagents, energy, and plant size, operating with lower values of operating variables. Thus, operating with 1.13% soda concentration and 2.25% hydrogen peroxide concentration for 3 hours, a pulp with a brightness of 75.1% (8.1% below the maximum and a viscosity of 740 mL/g (10.4% less than the maximum value, was obtained.

  20. [Endodontic treatment of primary teeth. Pulp exposure and pulp necrosis].

    Science.gov (United States)

    Gruythuysen, R J M

    2005-11-01

    With management of the deep caries in primary teeth we have to take account into the coping strategies of the patient and the state of the development of the dentition. That's why in most cases a root canal treatment of primary incisors or even a pulpotomy is not indicated. Often Intellectual Decision Not To Restore is a good alternative for treatment of deep caries in primary incisors. In deep caries lesions of primary canines and molars preferably minimal invasive techniques as indirect pulp capping are performed. In case of a exposure, the dentist can choose between several types of treatment. Improved techniques have lead to clinical satisfying results of the calcium hydroxide pulpotomy. A partial pulpotomy is if possible the treatment of choice. A resin modified glass ionomer cement is used to cover the pulp wound because it has good sealing properties and it is easy to handle. To limit the burden in young children a root canal treatment in primary teeth is seldom indicated. Overfilling with calcium hydroxide in root canal treatment of primary teeth never causes problems. PMID:16320568

  1. Enzymes improve ECF bleaching of pulp

    Directory of Open Access Journals (Sweden)

    Lachenal, D.

    2006-07-01

    Full Text Available The delignification efficiency of different laccase enzymes was examined on the eucalyptus Kraft pulp. The laccase enzyme from Trametes versicolor showing the highest delignification efficiency was selected and used in the elemental chlorine-free bleaching sequence for improving the pulp bleachability. An appreciable reduction in chlorine dioxide consumption was also obtained. Further reduction in chlorine dioxide consumption was obtained when the same laccase treated pulp was subjected to an acid treatment after the extraction stage followed by the DEPD sequence. Elemental-chlorine free bleaching was also performed using the xylanase-laccase treated pulp. Xylanase treatment was incorporated to the laccase mediator system in the elemental-chlorine free bleaching both sequentially and simultaneously. The bleaching sequence DEPD followed and in both the cases, the reduction in chlorine dioxide consumption was greater in comparison to the control. The chlorine dioxide consumption was reduced further when xylanase-laccase treated pulp was given an additional acid treatment. The final pulp properties of the treated pulps were comparable to the control pulp.

  2. Characterization of sugar beet pulp derived oligosaccharides

    NARCIS (Netherlands)

    Leijdekkers, M.

    2015-01-01

    Abstract This thesis aimed at characterizing complex mixtures of sugar beet pulp derived oligosaccharides, in order to be able to monitor and optimize the enzymatic saccharification of sugar beet pulp. Hydrophilic interaction chromatography with on-line evaporative light scattering

  3. PULP DEMAND IN THE INTERNATIONAL MARKET

    Directory of Open Access Journals (Sweden)

    Edmilson Santos Cruz

    2003-01-01

    Full Text Available This study aimed at analyzing the international pulp market, taking into account themain exporting countries and importing regions, with the objective of estimating, for each market, theown-price and cross-price elasticity in relation to the demand of the pulp, differentiated for country oforigin. The model considers that imports are differentiated by origin; therefore they are not perfect substitutes. The demand from Europe, North America and the Rest of the World for the pulp from theUnited States,Canada, Sweden, Finland, Portugal and Brazil was inelastic. The Asian demand for thissome pulp was elastic. Europe and the Rest of the World showed negative cross-price elasticity, i. e.,and the imported pulp from other countries are complementary products. North America and Asiashowed positive crow-price elasticity, i. e., they consider the pulp produced in other countries assubstitute products. The net effect of the variation on the price of pulp in a country h, over the amountof pulp that goes to the region i depends on the matching of values related to the elasticity ofsubstitution and the price elasticity of the total demand.

  4. Anti-scaling agents in kraft pulping

    Directory of Open Access Journals (Sweden)

    Felissia, F. E.

    2007-05-01

    Full Text Available Scale formation in the digester during kraft pulping represents a great problem in pulp mills. Scaling reduces pulping control and efficiency, increasing energy costs and leading to cleaning breakdowns, with subsequent losses in productivity. The kraft process promotes CaCO3 scaling due to high calcium ion and carbonate concentrations, as well as high alkalinity and temperature levels, which increase the speed with which liquors reach a state of supersaturation. This work examines the action of diethylene triamine penta(methylene phosphonic acid (DTPMPA, either alone or combined with commercial anti-scaling agents, as an inhibitor of calcium carbonate precipitation in the kraft pulping of Pinus taeda. The theoretical amount of calcium deposited in the digester was obtained by mass balance. Soluble calcium was stable throughout cooking when using the phosphonates alone or combined with anti-scaling agents. When adding only DTPMPA, calcium stays in the pulp, rather than forming deposits.

  5. Wood Pulp Digetster Wall Corrosion Investigation

    Energy Technology Data Exchange (ETDEWEB)

    Giles, GE

    2003-09-18

    The modeling of the flow in a wood pulp digester is but one component of the investigation of the corrosion of digesters. This report describes the development of a Near-Wall-Model (NWM) that is intended to couple with a CFD model that determines the flow, heat, and chemical species transport and reaction within the bulk flow of a digester. Lubrication theory approximations were chosen from which to develop a model that could determine the flow conditions within a thin layer near the vessel wall using information from the interior conditions provided by a CFD calculation of the complete digester. The other conditions will be determined by coupled solutions of the wood chip, heat, and chemical species transport and chemical reactions. The NWM was to couple with a digester performance code in an iterative fashion to provide more detailed information about the conditions within the NW region. Process Simulations, Ltd (PSL) is developing the digester performance code. This more detailed (and perhaps more accurate) information from the NWM was to provide an estimate of the conditions that could aggravate the corrosion at the wall. It is intended that this combined tool (NWM-PSL) could be used to understand conditions at/near the wall in order to develop methods to reduce the corrosion. However, development and testing of the NWM flow model took longer than anticipated and the other developments (energy and species transport, chemical reactions and linking with the PSL code) were not completed. The development and testing of the NWM are described in this report. In addition, the investigation of the potential effects of a clear layer (layer reduced in concentration of wood chips) near the wall is reported in Appendix D. The existence of a clear layer was found to enhance the flow near the wall.

  6. 漂白废报纸脱墨浆AKD施胶过程的湿部化学环境分析%Wet Chemical Environment Analysis of Alkyl Ketene Dimmers (AKD) Sizing of Bleached Waste Newspaper Deinked Pulp

    Institute of Scientific and Technical Information of China (English)

    韦黎; 曹云峰; 熊林根

    2011-01-01

    An L9(34)orthogonal test was designed to study the effects of AKD (alkyl ketene dimmers) charge, CS (cationic starch) charge, PCC (precipitated calcium carbonate) charge and CPAM (cationic polyacrylamide) charge on AKD sizing of bleached waste newspaper deinked pulp. And the optimal conditions were as follows: AKD dosage 0.4%, CS dosage 0.6%, PCC dosage 5% and CPAM dosage 0.03%. The variation tendency of sizing performance was essentially consistent with the Zeta potential value and cationic demand of furnish. In sizing process, Zeta potential and cationic demand of pulp was also an important factor, which was influential in the AKD sizing performance.%对漂白废报纸脱墨浆AXeD(烷基烯酮二聚物)施胶过程中AKD用量、CS(阳离子淀粉)用量、PCC(沉淀碳酸钙)用量和CPAM(阳离子聚丙烯酰胺)用量进行四因素三水平方差分析,当AKD用量为0.2%~0.4%(质量分数),CS用量为0.6%~1.0%,PCC用量为5%~15%,CPAM用量为0.03%-0.09%时,AKD施胶较为适宜工艺条件为:AKD用量0.4%,CS用量0.6%,PCC用量5%,CPAM用量0.03%。对纸浆动电特性的研究表明,成纸的施胶度基本与纸浆中的Zeta电位、浆料溶解电荷需求量的变化趋势一致。在施胶过程中,控制Zeta电位、浆料溶解电荷需求量也是影响AKD施胶效果的重要因素。

  7. Sludge from pulp and paper mills for biogas production : Strategies to improve energy performance in wastewater treatment and sludge management

    OpenAIRE

    Hagelqvist, Alina

    2013-01-01

    The production of pulp and paper is associated with the generation of large quantities of wastewater that has to be purified to avoid severe pollution of the environment. Wastewater purification in pulp and paper mills combines sedimentation, biological treatment, chemical precipitation, flotation and anaerobic treatment, and the specific combination of techniques is determined by the local conditions. Wastewater treatment generates large volumes of sludge that after dewatering can be inciner...

  8. [Effects of the treatment of coffee pulp, fresh or ensilaged, with calcium hydroxide, on its nutritive value].

    Science.gov (United States)

    Gómez-Brenes, R; Bendaña, G; González, J M; Jarquín, R; Braham, J E; Bressani, R

    1988-03-01

    This study was carried out to determine the effects of the addition of calcium hydroxide on the chemical composition and nutritive value of fresh or ensilaged coffee pulp. Fresh or ensilaged pulp were mixed with 1, 2 and 3% of calcium hydroxide. The process was carried out during 0 and 16 hr, after which time the treated pulp was sun-dried for 36 hr until moisture content reached 12%. These samples were then analyzed for their proximate chemical composition and for some minerals (Ca, P, Na, K), as well as for caffeine, tannins and chlorogenic and caffeic acids content. Diets were then prepared from these materials, containing 15% protein and 15 or 30% fresh or ensilaged coffee pulp, and offered to weanling rats during six weeks. Information required on weight gain, food conversion, apparent digestibility and toxicity of the diets was recorded. Results of the chemical analysis revealed that the main changes found in both types of pulp as a result of the calcium hydroxide treatment were the following: a decrease in ether extract (from 4.0 to 2.5 g/100 g), crude fiber (from 18.3 to 11.9 g/100 g) and protein content (from 12.3 to 8.6 g/100 g) in an inverse relation to the amount of calcium hydroxide used. The amount of ash increased, fluctuated between 5.5 and 15.4%, depending on the amount of calcium hydroxide used. The latter affected the Ca:P ratio in the diets, where an average ratio of 7.2:1 was found in the control pulp (0% calcium hydroxide) and 59.0:1 in those treated with the highest amount of calcium hydroxide (3%). Regarding the caffeine, tannins and chlorogenic and caffeic acids contents, calcium hydroxide was effective in decreasing only tannins, more so in the fresh than in the ensilaged pulp; the decrease was in direct proportion to the amount of calcium hydroxide added and to the length of the Ca(OH)2 treatment. The results of the biological assays showed that the addition of Ca(OH)2 in either of the two time periods used and at either of the

  9. A review on vital pulp therapy in primary teeth.

    Science.gov (United States)

    Parisay, Iman; Ghoddusi, Jamileh; Forghani, Maryam

    2015-01-01

    Maintaining deciduous teeth in function until their natural exfoliation is absolutely necessary. Vital pulp therapy (VPT) is a way of saving deciduous teeth. The most important factors in success of VPT are the early diagnosis of pulp and periradicular status, preservation of the pulp vitality and proper vascularization of the pulp. Development of new biomaterials with suitable biocompatibility and seal has changed the attitudes towards preserving the reversible pulp in cariously exposed teeth. Before exposure and irreversible involvement of the pulp, indirect pulp capping (IPC) is the treatment of choice, but after the spread of inflammation within the pulp chamber and establishment of irreversible pulpitis, removal of inflamed pulp tissue is recommended. In this review, new concepts in preservation of the healthy pulp tissue in deciduous teeth and induction of the reparative dentin formation with new biomaterials instead of devitalization and the consequent destruction of vital tissues are discussed. PMID:25598803

  10. On the beating of reinforcement pulp

    OpenAIRE

    Hiltunen, Eero

    2003-01-01

    The aim of this work was to gain a better understanding of the effect of reinforcement pulp beating on the strength of mechanical pulp-dominated paper. The main purpose of reinforcement pulp beating is to improve the runnability of paper. The first objective of this study was to maximize the runnability related strength properties by beating. It was assumed that the flaw-resisting ability of paper correlates with the runnability of the dry paper web. In-plane fracture properties were assumed ...

  11. SONOCHEMICALLY MODIFIED WHEAT STRAW FOR PULP AND PAPERMAKING IN ORDER TO INCREASE ITS ECONOMICAL RATES AND REDUCE THE ENVIRONMENTAL ISSUES

    Directory of Open Access Journals (Sweden)

    Levente Csoka

    2008-02-01

    Full Text Available Wheat straw (an agricultural by-product was pulped by an alkaline anthraquinone (AQ process. Then the straw pulp was treated by high-power ultrasound under different noble-gas (argon, krypton, xenon combinations. The pulps’ degree of beating and acid-insoluble lignin content were measured. Handsheets were made from sonicated and control pulps and tested for paper tensile strength. In this study we explore which noble-gas combination with ultrasound may be more useable to reduce the lignin content and enhance fibrillation. We also describe the most effective ultrasound-assisted, modified alkaline pulping process. Overall, we found that in two steps ultrasonification decreased the residual lignin contents more then 75 %, the pulp fibrillation increased from 12 to 70 °SR within 20 min. of ultrasound irradiation, and the tensile index of the handsheets increased by 65%. For sustainable paper production, it is required to develop alternative paper resources. Paper made from alternate fiber resources with efficient technology will improve our living standards without sacrificing the environment, our habitat. High frequency ultrasound-based pulp processing offers significant improvements, and it reduces energy and chemical consump-tions for pulp and paper production.

  12. SEM evaluation of pulp reaction to different pulp capping materials in dog’s teeth

    OpenAIRE

    Asgary, Saeed; Parirokh, Masoud; Eghbal, Mohammad Jafar; Ghoddusi, Jamileh

    2007-01-01

    Introduction: This investigation evaluates the effects of mineral trioxide aggregate (MTA), calcium hydroxide (CH) and calcium enriched mixture (CEM) as pulp capping materials on dental pulp tissues. Materials and Methods: The experimental procedures were performed on eighteen intact dog canine teeth. The pulps were exposed. Cavities were randomly filled with CEM, MTA, or CH followed by glass ionomer filling. After 2 months, animals were sacrificed, each tooth was sectioned into halves, and t...

  13. Conversion of Wood and Non-wood Paper-grade Pulps to Dissolving-grade Pulps

    OpenAIRE

    Köpcke, Viviana

    2010-01-01

    Dissolving-grade pulps are commonly used for the production of cellulose derivatives and regenerated cellulose. To obtain products of high quality, these so-called "special" pulps must fulfill certain requirements, such as high cellulose content, low hemicellulose content, a uniform molecular weight distribution and high cellulose reactivity. Most, if not all, of the commercial dissolving pulps accomplish these demands to a certain extent. Nevertheless, achieving high cellulose accessibility ...

  14. A New Technology for Treating Pulp Waste with Plasma

    Institute of Scientific and Technical Information of China (English)

    FENG Xiaozhen; TIAN Zhongyu

    2009-01-01

    New methods for both the treatment of pulp waste liquor called black liquor (BL) and the recovery of chemicals by using plasma,and the concentration of BL with the freezing technique were developed.The new methods aiming at the pilot plant scale are described and the experiments in a small-scale research facility for demonstration and test are presented.The energy consumption for treating waste liquid is 1 kg/kWh.Plasma processing can reduce the costs for treatment and eliminate pollution.

  15. 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.

  16. Structural and Chemical Characterization of Hardwood from Tree Species with Applications as Bioenergy Feedstocks

    OpenAIRE

    Çetinkol, Özgül Persil; Smith-Moritz, Andreia M.; Cheng, Gang; Lao, Jeemeng; George, Anthe; Hong, Kunlun; Henry, Robert; Simmons, Blake A.; Heazlewood, Joshua L.; Holmes, Bradley M

    2012-01-01

    Eucalypt species are a group of flowering trees widely used in pulp production for paper manufacture. For several decades, the wood pulp industry has focused research and development efforts on improving yields, growth rates and pulp quality through breeding and the genetic improvement of key tree species. Recently, this focus has shifted from the production of high quality pulps to the investigation of the use of eucalypts as feedstocks for biofuel production. Here the structure and chemical...

  17. Studies of chemical and enzymatic characteristics of Yacon (Smallanthus sonchifolius) and its flours

    OpenAIRE

    Juciane de Abreu Ribeiro Pereira; Maria de Fátima Píccolo Barcelos; Michel Cardoso de Angelis Pereira; Eric Batista Ferreira

    2013-01-01

    Due to the importance of studies on yacon related to health, its in natura pulp, in natura peel, pulp flour, and peel flour were chemically analyzed in terms of its centesimal composition, specific minerals, total dietary fiber and fractions, pH, total soluble solids, total titratable acidity, tannins, oxalic acid, and nitrate. The polyphenoloxidase and peroxidase enzymatic activities were evaluated for in natura pulp and peel only. Yacon pulp and peel flour presented average yield of 7.94% a...

  18. Cleaner Production of Wheat Straw Pulp

    Institute of Scientific and Technical Information of China (English)

    黄国林; 陈中胜; 张成芳

    2002-01-01

    A pulping method using NH4OH with less amount of KOH as cooking liquor on wheat straw was developed. KOH could reduce consumption of NH3 and cooking time for its strong alkalinity. The effects of various pulping conditions such as composition of cooking liquor, liquid-to-solid ratio, maximum temperature, cooking time to the maximum temperature and cooking time at the maximum temperature were studied. Experimental results indicated that the rate of delignification was 85.12( and the pulp yield was 49.65% under suitable pulping conditions. It looks promising to use black liquor containing nitrogen, phosphorus, potassium and organic substance as fertilizer resources for agricultural production. A new pattern of ecological cycling may be set up between paper industry and farming.

  19. Evaluation of the nutritive value of apple pulp mixed with different amounts of wheat straw

    OpenAIRE

    Rodrigues, M.A.M.; Guedes, C.M.; Rodrigues, A.; Cone, J.W.; Gelder, van, H.; Ferreira, L.M.M.

    2008-01-01

    Given the high amounts of apple rejected for commercialization its use as alternative feed for ruminants should be considered. This study was designed to investigate the nutritive value of apple pulp-wheat straw mixtures. Chemical composition, in vitro organic matter digestibility (IVOMD) and gas production profiles of ensiled mixtures containing 85 (M85), 70 (M70), and 50% (M50) of apple pulp were studied at 0, 15, 30 and 45 days. Fermentation quality was assessed by pH, lactic acid, ethanol...

  20. Fermentative characteristics of coffee pulp silage with different proportions of coffee hulls

    OpenAIRE

    Adauto Ferreira Barcelos; Valdir Botega Tavares; José Rodolfo Reis de Carvalho; Clenderson Corradi de Mattos Gonçalves

    2013-01-01

    This study aimed to evaluate the chemical composition and fermentation characteristics of the coffee pulp silages with different proportions of coffee hulls. The material was ensiled in PVC with 150 mm diameter by 750 mm high, according to the treatments: coffee pulp (CoP), CoP + 20% of coffee hulls (CH), CoP + 40% of CH and CoP + 60% CH in a completely randomized design with six replications. The silos were opened 60 days after closing, when samples were taken for determination of dry matter...

  1. Stability of frozen marolo pulp during storage

    Directory of Open Access Journals (Sweden)

    Clarissa Damiani

    2013-12-01

    Full Text Available Marolo, also known as araticum or head-to-black, is a globular berry, a species native to the Brazilian savannah. The aim of this study was to evaluate the physical, chemical, and microbiological stability of frozen marolo pulp during 12 months of frozen storage. It was observed that the levels of ash (0.28-0.22%, protein (0.77-0.71%, lipids (1.75-1.73%, carbohydrates (12.1-10.15%, calorie (67.23-59.01 kcal, sucrose (2.50-1.29%, citric acid (435.63-197.5 µg.g-1, tartaric acid (4.38-1.88 µg.g-1 , acetic acid (470.38-279.25 µg.g-1, ascorbic acid (3.00-0.00 µg.g-1, total pectin (0.67-0.39%, pH (3.88-3.83, and b* chromaticity coordinates (24.85-20.53 decreased reduced during storage, whereas the levels of moisture (85.10-87.19%, color parameters (L* 58.89-62.62 and a* 5.37-7.86, reducing sugars (4.53-5.62%, total soluble sugars (7.1-7.36%, soluble solids (7.0-8.4 ºBrix, total acidity (0.9-1.0%, malic acid (514.13-781.25 µg.g-1, soluble pectin (0.16-0.24%, and antioxidant (6.85-37.35% of DPPH discoloration increased over the one-year of storage period. According to the physical, chemical, and microbiological parameters assessed, the product can be stored for 12 months without loss of quality with addition of citric acid as a preservative.

  2. BLEACHING EUCALYPTUS PULPS WITH SHORT SEQUENCES

    OpenAIRE

    Flaviana Reis Milagres; Jorge Luiz Colodette; Marcos Sousa Rabelo; Danila Morais de Carvalho

    2011-01-01

    Eucalyptus spp kraft pulp, due to its high content of hexenuronic acids, is quite easy to bleach. Therefore, investigations have been made attempting to decrease the number of stages in the bleaching process in order to minimize capital costs. This study focused on the evaluation of short ECF (Elemental Chlorine Free) and TCF (Totally Chlorine Free) sequences for bleaching oxygen delignified Eucalyptus spp kraft pulp to 90% ISO brightness: PMoDP (Molybdenum catalyzed acid peroxide, chlorine d...

  3. Production of Biopolymers from Sugar Beet Pulp

    OpenAIRE

    Meyer, Laurence; Paquot, Michel; Dubois, Philippe

    2009-01-01

    Sugar beet pulp is an important by-product of the sugar industry. In order to make the most of this waste, pectin extraction can constitute an economical solution. Pectin is commonly used in food industry as a gelling agent. However, in the present study another use of pectin is considered: its potential embedding into biodegradable polymer films which can further be used in plastic industry. At first, different pectin extraction methods have been developed on sugar beet pulp in order t...

  4. Rheological evaluation of Prunus mume pulp

    Directory of Open Access Journals (Sweden)

    Ernesto Quast

    2013-12-01

    Full Text Available The rheological behaviour of mume pulp at 6, 7, 8 and 9 °Brix was investigated using a rotational viscometer at temperatures ranging from 15 to 75 °C. The rheological models of Herschel-Bulkley and Ostwald-Waele (Power Law were fitted to obtain the rheological parameters of the mume pulp. The product was described as time non-dependent and presented a viscosity of 1.9 Pa.s at 15 °C and 1.1°Pa.s at 65 and 75 °C for the 9 °Brix pulp. The pulp showed non-Newtonian behaviour and the Herschel-Bulkley model was used to describe this behaviour. The activation energy ranged from 6.6-10.6 kJ.mol-1 and the consistency index from 18.0-22.9 Pa.s n for the 9 °Brix pulp and 8.3-12.2 Pa.s n for the 8 °Brix pulp at temperatures varying from 15 to 75 °C. The models presented high correlation values for all the rheological data obtained in the present work.

  5. Treatment of the Bleaching Effluent from Sulfite Pulp Production by Ceramic Membrane Filtration

    Directory of Open Access Journals (Sweden)

    Mehrdad Ebrahimi

    2015-12-01

    Full Text Available Pulp and paper waste water is one of the major sources of industrial water pollution. This study tested the suitability of ceramic tubular membrane technology as an alternative to conventional waste water treatment in the pulp and paper industry. In this context, in series batch and semi-batch membrane processes comprising microfiltration, ultrafiltration and nanofiltration, ceramic membranes were developed to reduce the chemical oxygen demand (COD and remove residual lignin from the effluent flow during sulfite pulp production. A comparison of the ceramic membranes in terms of separation efficiency and performance revealed that the two-stage process configuration with microfiltration followed by ultrafiltration was most suitable for the efficient treatment of the alkaline bleaching effluent tested herein, reducing the COD concentration and residual lignin levels by more than 35% and 70%, respectively.

  6. Influence of process variables on the properties of laccase biobleached pulps.

    Science.gov (United States)

    Martin-Sampedro, Raquel; Miranda, Jesús; García-Fuentevilla, Luisa L; Hernández, Manuel; Arias, Maria E; Diaz, Manuel J; Eugenio, Maria E

    2015-01-01

    A laccase stage can be used as a pre-treatment of a standard chemical bleaching sequence to reduce environmental concerns associated to this process. The importance of each independent variable and its influence on the properties of the bleached pulp have been studied in depth in this work, using an adaptive network-based fuzzy inference system (ANFIS) with four independent variables (laccase, buffer, mediator and oxygen) as input. Eucalyptus globulus kraft pulp was biobleached using a laccase from Pycnoporus sanguineus and a natural mediator (acetosyringone). Later, an alkaline extraction and a hydrogen peroxide treatment were applied. Most biobleaching processes showed a decrease in kappa number and an increase in brightness with no significant impact on the viscosity values, compared with the control. Oxygen was the variable with the smallest influence on the final pulp properties while the laccase and buffer solution showed a significant influence. PMID:25085529

  7. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

    Directory of Open Access Journals (Sweden)

    Letizia Ferroni

    2015-03-01

    Full Text Available Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D hyaluronan scaffold and human dental pulp stem cells (DPSCs to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  8. Mg(OH2-BASED HYDROGEN PEROXIDE BLEACHING OF CMP PULPS AT HIGH CONSISTENCY

    Directory of Open Access Journals (Sweden)

    Pedram Fatehi

    2011-11-01

    Full Text Available The objective of this study was to investigate the bleaching performance of a Mg(OH2-based hydrogen peroxide process at a high consistency. In this work, an industrially produced chemimechanical pulp (CMP was bleached via Mg(OH2- or NaOH-based hydrogen peroxide processes at 10% and 25% consistencies. The results showed that the pulp bleached under the conditions of 1.5% Mg(OH2 and 3% H2O2 at 25% consistency had a similar brightness to, a lower yellowness index, and a higher opacity than the pulp produced under the conditions of 2.1% NaOH, 3% Na2SiO3, and 3% H2O2 at the same consistency. The temperature (70 ºC and time (150 min of the bleaching were the same for both processes. Under the conditions stated above, the Mg(OH2-based process had a higher yield than the NaOH-based process did. The bleaching effluent of the Mg(OH2-based process had a higher residual H2O2, but a lower Chemical Oxygen Demand (COD load and turbidity, compared with that of the NaOH-based process. However, the strength properties and water retention value (WRV of the pulp bleached via the Mg(OH2-based process were lower, while its bulk was higher than those of the pulp bleached via the NaOH-based process.

  9. Extracellular matrix of dental pulp stem cells: Applications in pulp tissue engineering using somatic MSCs

    Directory of Open Access Journals (Sweden)

    Sriram eRavindran

    2014-01-01

    Full Text Available Dental Caries affects approximately 90% of the world’s population. At present, the clinical treatment for dental caries is root canal therapy. This treatment results in loss of tooth sensitivity and vitality. Tissue engineering can potentially solve this problem by enabling regeneration of a functional pulp tissue. Dental pulp stem cells (DPSCs have been shown to be an excellent source for pulp regeneration. However, limited availability of these cells hinders its potential for clinical translation. We have investigated the possibility of using somatic mesenchymal stem cells from other sources for dental pulp tissue regeneration using a biomimetic dental pulp extracellular matrix (ECM incorporated scaffold. Human periodontal ligament stem cells (PDLSCs and human bone marrow stromal cells (HMSCs were investigated for their ability to differentiate towards an odontogenic lineage. In vitro real-time PCR results coupled with histological and immunohistochemical examination of the explanted tissues confirmed the ability of PDLSCs and HMSCs to form a vascularized pulp-like tissue. These findings indicate that the dental pulp stem derived ECM scaffold stimulated odontogenic differentiation of PDLSCs and HMSCs without the need for exogenous addition of growth and differentiation factors. This study represents a translational perspective toward possible therapeutic application of using a combination of somatic stem cells and extracellular matrix for pulp regeneration.

  10. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  11. 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

  12. Effect of tomato post-harvest fungicide treatment and storage conditions on the quality of fruits, and biological value of tomato pulp and concentrated pulp

    Directory of Open Access Journals (Sweden)

    H. Parynow

    2013-12-01

    Full Text Available The influence of storage conditions on the quality of tomato fruits was tested. The rate of ripening was established in normal air, where tomatoes ripen quickly, under controlled atmosphere where they ripen more slowly and under low pressure, where they ripen slowest. The influence of post-harvest benomyl or methylthiophanate treatment on tomato rot, ripening, and biological value were examined. Post-harvest tomato treatment did not reduce fruit rot. The color of fruits and the processed products depended on the fungicide treatment. Concentrated tomato pulp made of fruits treated with methylthiophanate was redder than the others. The fungicide treatment increased or decreased the level of some chemical substances in the fruits in dependence on the applied fungicide, storage conditions and the length of storage, e.g. tomatoes treated with benomyl and stored for 14 days contained the highest level of vitamin C under 0% CO2:3%O2 and tomatoes treated with methylthiophanate contained the highest level of vitamin C under 38 mm Hg. Degradation of vitamin C in pulp was faster than in the concentrated pulp. Tomato pulp made of tomatoes treated with methylthiophanate contained the lowest level of vitamin C.

  13. BLEACHING EUCALYPTUS PULPS WITH SHORT SEQUENCES

    Directory of Open Access Journals (Sweden)

    Flaviana Reis Milagres

    2011-03-01

    Full Text Available Eucalyptus spp kraft pulp, due to its high content of hexenuronic acids, is quite easy to bleach. Therefore, investigations have been made attempting to decrease the number of stages in the bleaching process in order to minimize capital costs. This study focused on the evaluation of short ECF (Elemental Chlorine Free and TCF (Totally Chlorine Free sequences for bleaching oxygen delignified Eucalyptus spp kraft pulp to 90% ISO brightness: PMoDP (Molybdenum catalyzed acid peroxide, chlorine dioxide and hydrogen peroxide, PMoD/P (Molybdenum catalyzed acid peroxide, chlorine dioxide and hydrogen peroxide, without washing PMoD(PO (Molybdenum catalyzed acid peroxide, chlorine dioxide and pressurized peroxide, D(EPODP (chlorine dioxide, extraction oxidative with oxygen and peroxide, chlorine dioxide and hydrogen peroxide, PMoQ(PO (Molybdenum catalyzed acid peroxide, DTPA and pressurized peroxide, and XPMoQ(PO (Enzyme, molybdenum catalyzed acid peroxide, DTPA and pressurized peroxide. Uncommon pulp treatments, such as molybdenum catalyzed acid peroxide (PMo and xylanase (X bleaching stages, were used. Among the ECF alternatives, the two-stage PMoD/P sequence proved highly cost-effective without affecting pulp quality in relation to the traditional D(EPODP sequence and produced better quality effluent in relation to the reference. However, a four stage sequence, XPMoQ(PO, was required to achieve full brightness using the TCF technology. This sequence was highly cost-effective although it only produced pulp of acceptable quality.

  14. STUDY ON ELIMINATING FLUORESCENCE IN COTTON PULP WITH PERACETIC ACID

    Institute of Scientific and Technical Information of China (English)

    Lixin Xu; Baoguo Sun

    2004-01-01

    This paper has studied processing conditions and the influence of every variable to the pulp when the fluorescence in cotton linter pulp is eliminated with peracetic acid. The suitable variables of the elimination of fluorescence. are found.

  15. STUDY ON ELIMINATING FLUORESCENCE IN COTTON PULP WITH PERACETIC ACID

    Institute of Scientific and Technical Information of China (English)

    LixinXu; BaoguoSun

    2004-01-01

    This paper has studied processing conditions and the influence of every variable to the pulp when the fluorescence in cotton linter pulp is eliminated with peracetic acid. The suitable variables of the elimination of fluorescence, are found.

  16. Laser Induced Fluorescence For Measurement Of Lignin Concentrations In Pulping Liquors

    Science.gov (United States)

    Horvath, J. J.; Semerjian, H. G.; Biasca, K. L.; Attala, R.

    1988-11-01

    Laser excited fluorescence of pulping liquors was investigated for use in the pulp and paper industry for process measurement and control applications. Liquors from both mill and laboratory cooks were studied. A Nd-YAG pumped dye laser was used to generate the excitation wavelength of 280 nm; measurements were also performed using a commercially available fluorometer. Measurements on mill pulping liquors gave strong signals and showed changes in the fluorescence intensity during the cook. Absorption spectra of diluted mill liquor samples showed large changes during the cook. Samples from well controlled and characterized laboratory cooks showed fluorescence to be linear with concentration over two decades with an upper limit of approximately 1000 ppm dissolved lignin. At the end of these cooks a possible chemical change was indicated by an increase in the observed fluorescence intensity. Results indicate that lignin concentrations in pulping liquors can be accurately determined with fluorescence in the linear optical region over a greater dynamic range than absorption spectroscopy. Laser induced fluorescence may also provide an indication of chemical changes occurring in the lignin structure during a cook.

  17. Pulp moulding machines for the production of packing paper elements

    OpenAIRE

    Lukić Ljubomir S.; Krgović Milorad V.; Jaraković Ilija M.

    2005-01-01

    Paper pulp molds are now commonly applied in the technology of modern packing for a wide range of products. The technological process of producing the paper molds has three basic phases: paper pulp preparation, in which water and waste paper are the basic raw materials, the formation of product in tool pulp moulding machines and process drying. The firm "SERVOTEH" from Belgrade has developed various pulp moulding machines for different operating conditions (manual, semiautomatic and automatic...

  18. Performance of a Horizontal Triple Cylinder Type Pulping Machine

    OpenAIRE

    Sukrisno Widyotomo; H. Ahmad; S.T. Soekarno; Sri Mulato

    2011-01-01

    Pulping is one important step in wet coffee processing method. Pulping process usually uses a machine which constructed by wood or metal materials. A horizontal single cylinder type of fresh coffee cherries pulping machine is the most popular machine in coffee processing. One of the weaknesses of a horizontal single cylinder type of fresh coffee cherries pulping machine is higher in broken beans. Broken bean is one of mayor aspects in defect system that contribute to low quality. Indonesian C...

  19. Histological effects of enamel matrix derivative on exposed dental pulp

    OpenAIRE

    Popović-Bajić Marijana; Danilović Vesna; Prokić Branislav; Prokić Bogomir Bolka; Manojlović Milica; Živković Slavoljub

    2015-01-01

    Introduction. Direct pulp capping procedure is a therapeutic application of a drug on exposed tooth pulp in order to ensure the closure of the pulp chamber and to allow the healing process to take place. Objective. The aim of this study was to examine the histological effects of Emdogain® on exposed tooth pulp of a Vietnamese pig (Sus scrofa verus). Methods. The study comprised 20 teeth of a Vietnamese pig. After class V preparation on the buccal surfaces o...

  20. Influence of xilanase treatment on Pinus pinaster kraft pulp

    OpenAIRE

    Spiridon, Iuliana; Duarte, Ana Paula; Curto, Joana

    2010-01-01

    In Portugal, pulp and paper industry uses especially two wood species, Eucalyptus globules and Pinus pinaster. The second species gives pulps with low bleachability (compared with other common softwood species, like Pinus silvester), utilised for packaging papers. It is known that treatments with different hydrolytic enzymes could improve the bleaching capacity of softwood pulp. That is why, xylanases were used to improve Pinus pinaster kraft pulp characteristics. The enzymatic hydrolysis imp...

  1. RAT DENTAL PULP RESPONSE TO PROPOLIS AS A DIRECT PULP CAPPING AGENT

    OpenAIRE

    Sabir Ardo

    2006-01-01

    The aim of the present study was to assess the response of rat dental pulp to direct pulp capping with ethanol extracts of propolis (EEP). An occlusal cavity was prepared on the right maxillary first molar of Spraque-Dawley rats. The dental pulp was exposed and the lined with a zinc-oxide based filler as a control (group I), or with EEP (group II). Then, each cavity was filled with glass ionomer cement. The animals were sacrificed at week 1, 2, or 4. Biopsy samples were obtained, and these we...

  2. The caries process and its effect on the pulp

    DEFF Research Database (Denmark)

    Bjørndal, Lars

    2008-01-01

    The understanding of the caries process and its effect on the pulp is presented in the context that caries does develop in various rates of progression. Early in the caries process, the pulp reflects changes within lesion activity. Thus, the early pulp response is reversible. Later, the rate of c...

  3. 21 CFR 176.260 - Pulp from reclaimed fiber.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Pulp from reclaimed fiber. 176.260 Section 176.260... for Use Only as Components of Paper and Paperboard § 176.260 Pulp from reclaimed fiber. (a) Pulp from reclaimed fiber may be safely used as a component of articles used in producing, manufacturing,...

  4. The anaerobic digestion of sugar beet pulp

    OpenAIRE

    Suhartini, Sri

    2014-01-01

    World-wide there are substantial quantities of sugar beet pulp, which arises as a residue after the processing of whole beet to extract sugar for refining as a foodstuff or for use in fermentation, in particular for the production of ethanol for the biofuel market. In both cases the resulting pulp residue is still rich in pentose sugars and fibre, and the research considered anaerobic digestion (AD) as a potential technology for the conversion of this material into renewable energy in the for...

  5. ALKALINE PEROXIDE MECHANICAL PULPING OF NOVEL BRAZILIAN EUCALYPTUS HYBRIDS

    Directory of Open Access Journals (Sweden)

    Marcelo Coelho dos Santos Muguet,

    2012-07-01

    Full Text Available Eucalyptus wood is among the most important biomass resource in the world. Wood mechanical defibration and fibrillation are energy-intensive processes utilized not only to produce pulp for papermaking, but also to produce reinforcement fibers for biocomposites, nanocellulose, or pretreat lignocellulosic material for biofuels production. The structural features of different Eucalyptus hybrids affecting the refining energy consumption and produced fiber furnish properties were evaluated. The defibration and fiber development were performed using an alkaline peroxide mechanical pulping (APMP process, which included chelation followed by an alkaline peroxide treatment prior to wood chip defibration. Despite the similar wood densities and chemical compositions of different Eucalyptus hybrids, there was a clear difference in the extent of defibration and fibrillation among the hybrids. The high energy consumption was related to a high amount of guaiacyl lignin. This observation is of major importance when considering the optimal wood hybrids for mechanical wood defibration and for understanding the fundamental phenomena taking place in chemi-mechanical defibration of wood.

  6. Integrated hydrolyzation and fermentation of sugar beet pulp to bioethanol.

    Science.gov (United States)

    Rezić, Tonči; Oros, Damir; Marković, Iva; Kracher, Daniel; Ludwig, Roland; Santek, Božidar

    2013-09-28

    Sugar beet pulp is an abundant industrial waste material that holds a great potential for bioethanol production owing to its high content of cellulose, hemicelluloses, and pectin. Its structural and chemical robustness limits the yield of fermentable sugars obtained by hydrolyzation and represents the main bottleneck for bioethanol production. Physical (ultrasound and thermal) pretreatment methods were tested and combined with enzymatic hydrolysis by cellulase and pectinase to evaluate the most efficient strategy. The optimized hydrolysis process was combined with a fermentation step using a Saccharomyces cerevisiae strain for ethanol production in a single-tank bioreactor. Optimal sugar beet pulp conversion was achieved at a concentration of 60 g/l (39% of dry weight) and a bioreactor stirrer speed of 960 rpm. The maximum ethanol yield was 0.1 g ethanol/g of dry weight (0.25 g ethanol/g total sugar content), the efficiency of ethanol production was 49%, and the productivity of the bioprocess was 0.29 g/l·h, respectively. PMID:23851274

  7. Bio-refinery system integrated with pulp and paper mills using black liquor gasification

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, Muhammad

    2010-07-01

    Mitigation of climate change and energy security are major driving forces for increased biomass energy utilization. The pulp and paper industry consumes a large proportion of biomass worldwide that include bark, wood residues, and black liquor. Due to the fact that modern pulp and paper industries have established infrastructure for handling and processing biomass, it is possible to lay foundation for future gasification based bio-refineries to co-produce electricity, chemicals or bio-fuels together with pulp and paper products. There is a potential to export electricity or bio-fuels by improving today's existing chemical pulp and paper mills integrating gasification technology.The present study evaluates the energy conversion performance of integrated black liquor gasification (BLG) within the chemical pulp mills in comparison with conventional pulp mill energy system. The objective is to investigate and compare various BLG technologies and bio-fuel production routes. The comparison is performed to identify the advantageous route based on system performance indicators e.g. bio-fuel production potential, fuel to product efficiency (FTPE), biomass import, overall system thermal energy efficiency, on-site CO{sub 2} reduction using carbon capture, and potential CO{sub 2} offsets from bio-fuel use in transport sector.The study on a variety of BLG configurations shows promising results for potential bio-fuel production offering significant contributions toward fossil fuel savings, emission reductions, and improved energy security. Methanol, synthetic natural gas (SNG) and dimethyl ether (DME) show promising features as potential fuel candidates. The comparative results show significantly larger bio-fuel production potential of black liquor conversion to SNG from catalytic hydrothermal gasification than DME, methanol or SNG production from the dry BLG (DBLG) and Chemrec BLG (CBLG) systems. The energy ratio of SNG production from the CHG system is higher than DME and

  8. The influence of the extraction parameters on the quality of dried sugar beet pulp

    Directory of Open Access Journals (Sweden)

    Bogdanović Branislav V.

    2013-01-01

    but relatively mild changes in the characteristics of extracted and dried sugar beet pulp compared to conditions when hydrogen peroxide is used. From the point of the quality of the product of extraction, the most favorable results are obtained when the extraction is carried on at pH 5.5 for a period of 1 h at 70 °C, using water for extraction with sulphourus acid with the addition of 5% hydrogen peroxide. Under these conditions no significant degradation of sugar beet tissue is detected, do not change the physical, chemical and mechanical properties of the extracted pulp. But there is an average increase of lightness of dried noodles for about 7 units, which represents a significant improvement of their quality, since there is difficult to sell on the market the dried sugar beet pulp with increased colour.

  9. Microwave Measurements of Low Pulp Concentration in Papermaking Process

    Science.gov (United States)

    Nakayama, Shigeru

    1994-06-01

    A method of microwave measurements of low pulp concentrations in the papermaking process is developed using a coaxial cavity resonator with an inner slot antenna. We measure the attenuation of the resonant peak of the cavity resonator which is related to the pulp concentration. The pulp concentration up to 10.1% is measured, and then the linear relationship between the attenuation and low pulp concentrations down to 0.6% is determined. By this method, a low pulp concentration can be measured within the standard deviation of 0.03% by linear approximation.

  10. Perawatan Indirect Pulp Capping pada Gigi Tetap Muda (Laporan Kasus

    Directory of Open Access Journals (Sweden)

    Suzanty Ariany

    2015-11-01

    Full Text Available Treatment for young permanent teeth with deep carious lesion that on radiographic examination close to the pulp and without symptoms and sign of pulp degeneration are indirect pulp capping. The aim of this technique is to maintain pulp vitality. Material used for this treatment must be able to stimulate reparative dentin, such as calcium hydroxide, zinc oxide eugenol, glass ionomer cement and bonding agent. This paper reported indirect pulp capping on young permanent tooth with deep carious lesion. After 7 months of observation there was no symptom and on radiographic examination showed reparative dentin.

  11. Pulp supply optimization – Case M-real

    OpenAIRE

    Ilmonen, Kai

    2010-01-01

    The objective of this study was to develop a pulp supply optimization model, a management decision support tool, which would efficiently optimize the allocation of the pulp within the company’s supply chain in such a way that the company’s added value is maximized. The company’s current situation and operational methods were carefully analyzed in order to build an accurate linear model that would optimize pulp allocation from the company’s pulp mills and external pulp suppliers to the company...

  12. Biosynthesis of pectinolytic enzymes by Aspergillus on apple pulp

    OpenAIRE

    Mojsov, Kiro; Petreska, Meri; Ziberoski, Jugoslav

    2012-01-01

    The aim of this work was to develop a low cost process for apple pulp utilization. The apple pulp combined with corn flour and simple mineral salts by submerged production of pectinolytic enzymes by the fungus Aspergillus. Different concentration on apple pulp and different pH initial on the bases were studied, and all other process parameters were same. Results of different concentration on apple pulp gived maximal endo- PG with 1% apple pulp, during from 96 h, and the growth of the micr...

  13. Report of the OCVCI-PAPRICAN forest-based chemicals biorefinery Northern Ontario Commercialization Initiative workshop

    Energy Technology Data Exchange (ETDEWEB)

    Magdzinski, L. (ed.)

    2007-07-01

    This workshop was held to establish commercial processes for the generation of sustainable chemical feedstock from pulp mills. The workshop was attended by over 60 participants from the pulp and paper industry as well as members of the chemical, forestry, and industrial biotechnology industries. Representatives from governments and academic institutions also attended. Links were established between the Ontario forest sector and the Ontario chemical and and polymer sectors. The workshop presented a range of topics for discussion among participants, including issues related to the development of industrial chemicals from pulp mills and methods of sustainably extracting chemicals from hemicellulose. Issues related to the development of bioplastics from pulp production were discussed as well as new developments in wood-derived pharmaceuticals and nutraceuticals. Ontario forestry resources were reviewed, and a Paprican biorefinery agenda was presented. Current pulp mill bio-based chemicals were discussed, and sustainable feedstocks for the production of chemicals were identified. Industrial bioconversion processes were also outlined.

  14. 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

  15. 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.

  16. 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.

  17. Influence of different types of pulp treatment during isolation in the obtention of human dental pulp stem cells

    Science.gov (United States)

    Viña-Almunia, Jose; Borras, Consuelo; Gambini, Juan; El Alamy, Marya; Viña, Jose

    2016-01-01

    Background Different methods have been used in order to isolate dental pulp stem cells. The aim of this study was to study the effect of different types of pulp treatment during isolation, under 3% O2 conditions, in the time needed and the efficacy for obtaining dental pulp stem cells. Material and Methods One hundred and twenty dental pulps were used to isolate dental pulp stem cells treating the pulp tissue during isolation using 9 different methods, using digestive, disgregation, or mechanical agents, or combining them. The cells were positive for CD133, Oct4, Nestin, Stro-1, CD34 markers, and negative for the hematopoietic cell marker CD-45, thus confirming the presence of mesenchymal stem cells. The efficacy of dental pulp stem cells obtention and the minimum time needed to obtain such cells comparing the 9 different methods was analyzed. Results Dental pulp stem cells were obtained from 97 of the 120 pulps used in the study, i.e. 80.8% of the cases. They were obtained with all the methods used except with mechanical fragmentation of the pulp, where no enzymatic digestion was performed. The minimum time needed to isolate dental pulp stem cells was 8 hours, digesting with 2mg/ml EDTA for 10 minutes, 4mg/ml of type I collagenase, 4mg/ml of type II dispase for 40 minutes, 13ng/ml of thermolysine for 40 minutes and sonicating the culture for one minute. Conclusions Dental pulp stem cells were obtained in 97 cases from a series of 120 pulps. The time for obtaining dental pulp stem cells was reduced maximally, without compromising the obtention of the cells, by combining digestive, disgregation, and mechanical agents. Key words:Dental pulp stem cells, mesenchymal stem cells, isolation method. PMID:26946201

  18. Pulp-Capping with Mineral Trioxide Aggregate

    Directory of Open Access Journals (Sweden)

    Peycheva Kalina

    2015-11-01

    Full Text Available There are two considerations for direct pulp capping - accidental mechanical pulp exposure and exposure caused by caries. Mineral trioxide aggregate (MTA was used as pulp-capping material to preserve the vitality of the pulpal tissues. Follow-up examinations revealed that treatment was successful in preserving pulpal vitality and continued development of the tooth. On the basis of available information, it appears that MTA is the material of choice for some clinical applications. Material and methods: Cases 18 - 8 teeth with grey MTA, 10 teeth with white MTA; diagnose: Pulpitis chronica ulcerosa, Electro pulpal test (EOD - 30-35 μA, pre-clinical X-ray - without changes in the structures, follow ups for 4 years. Successful treatments: without clinical symptoms and changes in the X-rays: 5 teeth with grey MTA, 8 teeth with white MTA for period of 4 years. Unsuccessful treatments: Clinical symptoms and sometimes changes in the X-ray: 3 with grey MTA, 2 with white MTA. MTA is an appropriate material for pulp-capping and follow-up examinations revealed that the treatment was successful in preserving pulpal vitality.

  19. Radiation -adsorption treatment of pesticides by using wood pulp and bagasse pulp

    International Nuclear Information System (INIS)

    Alkaline pulping of pulp wood and bagasse using sodium hydroxide resulted in the reduction of lignin from the wood and bagasse fibers and consequently increase adsorption of the pesticide pollutants to these fibers. Three different types of pesticides were used in this study namely, metalaxyl, dicloran and arelon. which were irradiated at a dose of 4 kGy before adsorption treatment.The results show that moderate adsorption was observed for all pesticides when adsorption was carried out without alkaline pulping and irradiation. This is due to the presence of lignin which retard the adsorption process. Batch sorption experiments at different pH values (3, 7, 9) for the retention of these pesticides by pulp wood and pulp bagasse fibers indicated that sorption is governed by the interaction of the ionized form of these compounds with the polyhydroxyl structure of cellulose. The study shows that alkaline pulping of pulpwood and bagasse improves its ability towards adsorption of the radiation degraded pesticide molecules

  20. Nanofibrillated cellulose as paper additive in Eucalyptus pulps

    Directory of Open Access Journals (Sweden)

    Israel González

    2012-11-01

    Full Text Available In this work, the physical and mechanical properties of bleached Eucalyptus pulp reinforced with nanofibrillated cellulose (NFC are compared with those of traditional beaten pulp used in the making of writing/printing and offset printing papers. For this purpose, three different types of hardwood slurries were prepared: beaten pulps, unbeaten pulps reinforced with NFC, and slightly beaten pulps also reinforced with NFC. Physical and mechanical tests were performed on handsheets from these different slurries. The results showed that adding NFC to unbeaten pulps results in physical and mechanical properties similar to those in pulps used for printing/writing papers. Nevertheless, the best results were obtained in slurries previously beaten at slight conditions and subsequently reinforced with NFC. These results demonstrate that the addition of NFC allows a reduction in beating intensity without decreasing the desired mechanical properties for this specific purpose.

  1. 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

  2. TESTING OF PULP VITALITY BY PULSOXIMETRY

    Directory of Open Access Journals (Sweden)

    Gabriela CIOBANU

    2012-06-01

    Full Text Available The methods applied for diagnosing the health condition of the pulp tissue are numerous, however, nowadays, an increasingly higher number of conventional tests are replaced by some objective, non-invasive, painless and reliable tests. Among them, pulse oximetry is a method for the investigation of pulp vitality based on oxygen saturation (SaO2 of the hemoglobin from the blood present in the pulp vascular bed, as a means of differentiating among the vital and the non-vital teeth. In the present study, registrations were made on a group of 120 frontal maxillary teeth, in patients with ages between 20 and 40 years, on using a digital sensor modified by the pulse oximeter with which the pulse and the values of oxygen saturation were measured at the level of both teeth and right hand finger. The mean SaO2 value in the pulp blood of the vital teeth was of 83.30% for the central incisor, of 78.51% for the lateral one and of 84.56%, respectively, for the canine; the value recorded at finger level was of 97%. In the non-vital teeth, the SaO2 value measured on the pulse oximeter was of 0%. Pulse registration showed mean values of 70.56 beatings/min at tooth level and of 70.88 beatings/min, respectively, at finger level. The results of the present study may confirm that pulse oximetry represents a simple, non-traumatic, efficient and objective method for testing the vitality condition of the dental pulp.

  3. Investigating the possibility of chemi-mechanical pulping of bagasse

    Directory of Open Access Journals (Sweden)

    Alireza Khakifirooz

    2013-02-01

    Full Text Available Chemi-mechanical pulping was evaluated as a potential way to prepare sugarcane bagasse fibers for papermaking. Cellulose, lignin, ash, and extractives soluble in alcohol-acetone were measured as 55.75%, 20.5%, 1.85%, and 3.25%, respectively. Fiber length, diameter, lumen cavity, and cell wall thickness were measured as 1.59 mm, 20.96, 9.72, and 5.64 µm. The chemi-mechanical pulping conditions were selected as follows: three charging levels of 10, 15, and 20% sodium sulphite, and three pulping times of 20, 30, and 40 minutes after reaching the pulping temperature. Pulping temperature was held constant at 165 C. Different pulping conditions resulted in pulp yields between 65.38 and 84.28%. The highest yield (84.28% was obtained using a treatment combination of 20 minutes pulping time and 10% sodium sulphite. The lowest yield (65.38% was related to 40 minutes pulping time and 20% sodium sulphite. Pulps were refined to 300 ± 25 mL CSF, 60 gm-2 handsheets were made, and then strength indices and optical properties of the handsheets were measured. The results showed that 20% sodium sulphite, 40 minutes pulping time, at 165 ºC can be considered as the optimum pulping conditions for bagasse CMP pulping. Tensile, tear, and burst strength indices, as well as the opacity of this pulp were measured as 39.59 Nmg-1, 6.66 mNm2g-1, 2.1 KPa m2g-1, and 95.35%, respectively.

  4. Nutritional Content and Antioxidant Properties of Pulp Waste from Daucus carota and Beta vulgaris.

    Science.gov (United States)

    Shyamala, B N; Jamuna, P

    2010-12-01

    This study reports the chemical composition and antioxidant potential of pulp waste from two vegetables, carrot (Daucus carota) and beetroot (Beta vulgaris). Different in vitro assays used for determining antioxidant potential of extracts of pulp wastes were: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, reducing power and total antioxidant activity by phosphomolybdenum method. Total polyphenols, tannins and antioxidative components such as vitamin C, total carotenoids and β-carotene were analysed in the samples. The moisture content of samples ranged from 79 - 84%. The protein content was high in beetroot (13.23 mg/100g) and low in carrot (6.21mg/100g). Total polyphenols were higher in methanol extracts of samples (220-250 mg/100g) compared to ethanol and aqueous extracts. The antioxidant activity determined by the DPPH method exhibited 40% and 78% activity in methanol extracts of carrot and beetroot pulp waste (20 mg) respectively. Overall, the results suggest that carrot and beetroot pulp wastes can be exploited for their nutrients and antioxidant components and used for value addition in food formulations. Hence, these results pave the way for utilisation of bio-wastes from the food industry. PMID:22691993

  5. Thorough Characterization of Brazilian New Generation of Eucalypt Clones and Grass for Pulp Production

    Directory of Open Access Journals (Sweden)

    Fernando José Borges Gomes

    2015-01-01

    Full Text Available Eucalypt wood is becoming the most important raw material for the pulp industries in South America. However, due to the high wood cost in comparison to other raw material sources, nonwoody materials are also being investigated aiming at pulp production. In this way, this paper aimed at the evaluation of eighteen eucalypt clones obtained from the Brazilian Genolyptus project, regarding their potential characteristics for pulp production. Aiming at the same goal, two species of elephant grass were also evaluated as alternative raw material sources. Through the analyses of the anatomic and chemical characteristics, five eucalypt clones and one elephant grass species were indicated for pulp production and biorefinery application. The results of this study indicate the high technological quality of Eucalyptus clones evaluated and indicate that they can be used for biorefinery applications since they have the suitable characteristics. In general, the eucalypt clones are less moist and denser and contain fewer minerals and extraneous materials than the elephant grass species, which make them more attractive for utilization in deconstruction studies aiming at production of bioproducts.

  6. Anaerobic treatment of residual lemon pulp in digesters with semi-continuous feed.

    Science.gov (United States)

    Navarro, A R; Lopez, Z; Salguero, J; Maldonado, M C

    2013-01-01

    Lemon growing areas in the north of Argentina have industries that produce concentrated juice, peel and essential oil and generate a significant amount of liquid and solid waste as lemon pulp. In Argentina, despite the potential applications that the pulp has as animal feed and human and industrial raw material, only 10% is used for these purposes and the rest is discarded into the environment causing many ecological and economic problems. There is little information in the literature on biotechnologies for the treatment of this industrial waste. This paper shows that lemon pulp is a suitable substrate to be treated by anaerobic digestion. We obtained 86 and 92% reduction of chemical oxygen demand in a digester with a semi-continuous feed and retention time of 10 and 20 days respectively and a productivity of 0.406 g CH(4)/g VS h. Comparative tests showed that pre-digesting the pulp improved the process of digestion and increased biogas generation by 20%. PMID:23202554

  7. The Potential in Bioethanol Production From Waste Fiber Sludges in Pulp Mill-Based Biorefineries

    Science.gov (United States)

    Sjöde, Anders; Alriksson, Björn; Jönsson, Leif J.; Nilvebrant, Nils-Olof

    Industrial production of bioethanol from fibers that are unusable for pulp production in pulp mills offers an approach to product diversification and more efficient exploitation of the raw material. In an attempt to utilize fibers flowing to the biological waste treatment, selected fiber sludges from three different pulp mills were collected, chemically analyzed, enzymatically hydrolyzed, and fermented for bioethanol production. Another aim was to produce solid residues with higher heat values than those of the original fiber sludges to gain a better fuel for combustion. The glucan content ranged between 32 and 66% of the dry matter. The lignin content varied considerably (1-25%), as did the content of wood extractives (0.2-5.8%). Hydrolysates obtained using enzymatic hydrolysis were found to be readily fermentable using Saccharomyces cerevisiae. Hydrolysis resulted in improved heat values compared with corresponding untreated fiber sludges. Oligomeric xylan fragments in the solid residue obtained after enzymatic hydrolysis were identified using matrix-assisted laser desorption ionization-time of flight and their potential as a new product of a pulp mill-based biorefinery is discussed.

  8. Failure analysis of a heat exchanger used of a wood pulp bleaching process

    International Nuclear Information System (INIS)

    This study involved an investigation of the failure of a heat exchanger used in the ozone destruction stage of a wood pulp bleaching process at a pulp plant. The following procedures were carried out to determine the causes of the failure: a chemical analysis of the component, atomic absorption spectroscopy, measurements of hardness and of corrosion-related mass loss, characterization by scanning electron microscopy, and chemical microanalysis by X-ray energy dispersive spectroscopy. The corrosion damage of the heat exchanger was caused by chloric and sulfuric acid, which led to pitting, grooving and cracking, as well as generalized corrosion of the component (AISI 316L steel). Nitric acid caused minimal damage to the heat exchanger, with minor generalized corrosion and occasional pitting. White crystals rich in sulfur and chlorine were identified as the corrosive agents acting inside the heat exchanger. (author)

  9. Optimum dose of 2-hydroxyethyl methacrylate based bonding material on pulp cells toxicity

    OpenAIRE

    Widya Saraswati

    2010-01-01

    Background: 2-hydroxyethyl methacrylate (HEMA), one type of resins commonly used as bonding base material, is commonly used due to its advantageous chemical characteristics. Several preliminary studies indicated that resin is a material capable to induce damage in dentin-pulp complex. It is necessary to perform further investigation related with its biological safety for hard and soft tissues in oral cavity. Purpose: The author performed an in vitro test to find optimum dose of HEMA resin mon...

  10. Cancer Chemoprevention by Citrus Pulp and Juices Containing High Amounts of β -Cryptoxanthin and Hesperidin

    OpenAIRE

    Mayu Tanaka; Toshiya Kuno; Takahiro Tanaka; Takuji Tanaka

    2011-01-01

    β -Cryptoxanthin, a carotenoid, and hesperidin, a flavonoid, possess inhibitory effects on carcinogenesis in several tissues. We recently have prepared a pulp (CHRP) and citrus juices (MJ2 and MJ5) from a satsuma mandarin (Citrus unshiu Mar.) juice (MJ). They contain high amounts of β -cryptoxanthin and hesperidin. We have demonstrated that CHRP and/or MJs inhibit chemically induced rat colon, rat tongue, and mouse lung tumorigenesis. Gavage with CHRP resulted in an increase of activities of ...

  11. Application of alkaline waste from pulp industry to acid soil with pine

    OpenAIRE

    Patricia Pértile; Jackson Adriano Albuquerque; Luciano Colpo Gatiboni; André da Costa; Maria Izabel Warmling

    2012-01-01

    In Brazil extensive areas are covered with pine forests, planted for pulp and paper production. This industry generates solid alkaline waste, such as dregs. The application of this dregs to forest soils is an alternative for soil acidity correction and plant nutrient supply, as well as a solution for its proper disposal. The purpose of this study was to compare the residual effect of surface application of dregs and dolomitic lime on (a) changes in the physical and chemical properties of an a...

  12. Enzymatic approaches in paper industry for pulp refining and biofilm control

    OpenAIRE

    Torres, Esperanza; Negro Álvarez, Carlos; Fuente González, Elena de la; Blanco Suárez, Ángeles

    2012-01-01

    The use of enzymes has a high potential in the pulp and paper industry to improve the economics of the paper production process and to achieve, at the same time, a reduced environmental impact. Specific enzymes contribute to reduce the amount of chemicals and energy required for the modification of fibers and helps to prevent the formation or development of biofilms. This review is aimed at presenting the latest progresses made in the application of enzymes as refining aids and biofilm contro...

  13. Modifikasi Permukaan Serbuk Pulp Tandan Kosong Sawit Dengan Anhidrida Asetat Sebagai Bahan Pengisi Polipropelina

    OpenAIRE

    Vivi Purwandari

    2008-01-01

    Empty fruit bunches of oil palm is a waste of oil palm industries that contain high celluloid fibers as raw material for pulp production. On the other hand, cellulose fibers have been used as fillers to improve mechanical properties of polypropylene matrix. However, there is polarity difference between the cellulose fillers and the polymer matrix so a compatibilizer is needed to decrease the polarity of cellulose filler. This can be done by chemical modification of the filler surface such as ...

  14. Efeito da aplicação de água residuária da lavagem dos frutos de café sobre as propriedades químicas do solo Effect of the application of coffee fruit washing and pulping wastewater on soil chemical properties

    Directory of Open Access Journals (Sweden)

    George B Silva

    2011-02-01

    Full Text Available O objetivo deste trabalho foi avaliar as alterações químicas de solos tratados com água residuária de café (ARC. O experimento foi conduzido em colunas de PVC, onde foram avaliadas quatro doses de ARC (0; 174; 522 e 870 t ha-1, em dois Argissolos Amarelos subdivididos em quatro camadas, para dois períodos de incubação (30 e 60 dias. O delineamento experimental foi o inteiramente casualizado, em arranjo fatorial, e as variáveis analisadas foram cálcio, magnésio, potássio, sódio, pH e condutividade elétrica do extrato da pasta saturada. As doses de ARC alteraram as propriedades químicas dos solos nos dois períodos de incubação estudados, aumentando os teores de Ca++, Na+ e, principalmente, K+ nos dois solos. A dose de aplicação de 174 t ha-1 de ARC elevou a concentração de K+ no solo para a faixa ideal, de acordo com as exigências nutricionais da cultura. A camada superficial apresentou maior concentração de K+, Na+, Ca++ e, consequentemente, maior CEes.The objective of the present study was to evaluate chemical changes of soils treated with coffee fruit washing and pulping wastewater (CWW. The experiment was carried out in PVC columns, where it was applied four doses of CWW (0, 174, 522, and 870 t ha-1 in two Yellow Argisoil split into four layers in two incubation periods (30 and 60 days. The experimental design was completely randomized in a factorial arrangement, and it was analyzed calcium, magnesium, potassium, sodium, pH and electric conductivity of the saturated paste extract. The CWW doses affected chemical soil properties in both incubation periods evaluated increasing Ca++, Na+ and mainly K+ in both soils. The CWW dose of 174 t ha-1 increased K+ concentration in soil to the recommended level according to nutrition necessity of the crop. The surface layer presented higher concentration of K+, Na+, Ca++ and, consequently, higher ECes.

  15. PREPARATION OF XYLOSE AND KRAFT PULP FROM POPLAR BASED ON FORMIC/ACETIC ACID /WATER SYSTEM HYDROLYSIS

    Directory of Open Access Journals (Sweden)

    Junping Zhuang

    2009-08-01

    Full Text Available A formic/acetic acid/water system was used in the ratios of 30:60:10, 20:60:20, and 30:50:20 separately for efficient hydrolysis and bioconversion of poplar chips, under the solid/liquid ratio of 1:12(g/ml, at 105 oC for 30, 45, 60, 75, and 90 min, respectively. The highest yield of 69.89% was at a formic/acetic acid /water ratio of 30:50:20(v/v/v, with solid/liquid in the ratio of 1:12(g/ml at 105 oC for 90min. Lower kappa number and similar yield were achieved when hydrolytic residual woodchips were used for kraft pulping with over 2% Na2O and temperature 5 °C lower compared to untreated chips. Pulps from prehydrolysis-treated chips were easy to beat. But the tensile index, tear index, and burst index of the handsheets obtained from pulp with lowest kappa number from prehydrolysis-treated poplar chips were lower than those of the pulp from the untreated chips. Considerable xylose could be obtained from the prehydrolysis stage following kraft pulping under the same conditions for prehydrolysis-treated chips and untreated chips. However, by building on the mature kraft pulping and xylitol processes, large amounts of xylose from the hemicellulose were obtained in prehydrolysis, allowing production of high-valued products via biorefinery pathways. An economical balance of chemical dosage, energy consumption, pulp properties, and xylose value for prehydrolysis with organic acid should be reached with further investigation.

  16. 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.

  17. Evaluating pulp stiffness from fibre bundles by ultrasound

    International Nuclear Information System (INIS)

    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. (paper)

  18. 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

  19. Fermentative characteristics of coffee pulp silage with different proportions of coffee hulls

    Directory of Open Access Journals (Sweden)

    Adauto Ferreira Barcelos

    2013-03-01

    Full Text Available This study aimed to evaluate the chemical composition and fermentation characteristics of the coffee pulp silages with different proportions of coffee hulls. The material was ensiled in PVC with 150 mm diameter by 750 mm high, according to the treatments: coffee pulp (CoP, CoP + 20% of coffee hulls (CH, CoP + 40% of CH and CoP + 60% CH in a completely randomized design with six replications. The silos were opened 60 days after closing, when samples were taken for determination of dry matter (DM, crude protein (CP, neutral detergent fiber (NDF, acid detergent fiber (ADF, lignin, cellulose, pH, N-NH3, caffeine, calcium (Ca, phosphorus (P and in vitro digestibility of dry matter. We also determined gas production and effluent. There was a linear increase in DM content and pH, and a linear decrease of CP, NDF and ADF, lignin, cellulose, caffeine, Ca and P. This reduction occurs because the coffee hulls have lower levels than pulp to CP, NDF, ADF, caffeine, Ca and P. There was also a linear reduction in N-NH3 values, and only the highest percentage of silage with coffee hulls obtained below 10%, considered as the limit for good quality silage. Effluent production was higher for silage shelled coffee pulp and do not get any production in silage with 60% coffee hull. There was no significant difference in vitro digestibility of dry matter among treatments. The coffee hulls was effective in increasing DM content of CoP silage and to reduce NDF, ADF, N-NH3, providing nutritional value of silage satisfactory for cattle feed, creating an alternative for recovery of such waste. When considering the DM content found in silages, the amount of bark best coffee to be added to coffee pulp for the production of silage is between 30% and 35%.

  20. 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

  1. RAT DENTAL PULP RESPONSE TO PROPOLIS AS A DIRECT PULP CAPPING AGENT

    Directory of Open Access Journals (Sweden)

    Sabir Ardo

    2006-04-01

    Full Text Available The aim of the present study was to assess the response of rat dental pulp to direct pulp capping with ethanol extracts of propolis (EEP. An occlusal cavity was prepared on the right maxillary first molar of Spraque-Dawley rats. The dental pulp was exposed and the lined with a zinc-oxide based filler as a control (group I, or with EEP (group II. Then, each cavity was filled with glass ionomer cement. The animals were sacrificed at week 1, 2, or 4. Biopsy samples were obtained, and these were stained and viewed by a light microscope. The histological examination was based on the presence of polymorph nuclear leukocytes and macrophages, and also the dentinal bridge formation. Data were statistically analysed using Kruskall-Wallis and Mann-Whitney tests. The results showed that the inflammatory response of EEP group was relatively milder compared to the control group, but there was no significant difference (p>0.05 between the two groups. There was no dentinal bridge formation seen in both groups. Therefore, the present results suggest that direct pulp capping with EEP in rats may delay pulp inflammatory process and fail to stimulate reparative dentin.

  2. Expression of high mobility group box 1 in inflamed dental pulp and its chemotactic effect on dental pulp cells

    International Nuclear Information System (INIS)

    Highlights: • HMGB1 translocated from nucleus to cytoplasm during dental pulp inflammation. • HMGB1and its receptor RAGE were up-regulated in hDPCs under LPS stimulation. • HMGB1 enhanced hDPCs migration and induces cytoskeleton reorganization. • HMGB1 may play a critical role in dental pulp repair during inflamed state. - Abstract: High mobility group box 1 protein (HMGB1) is a chromatin protein which can be released extracellularly, eliciting a pro-inflammatory response and promoting tissue repair process. This study aimed to examine the expression and distribution of HMGB1 and its receptor RAGE in inflamed dental pulp tissues, and to assess its effects on proliferation, migration and cytoskeleton of cultured human dental pulp cells (DPCs). Our data demonstrated that cytoplasmic expression of HMGB1 was observed in inflamed pulp tissues, while HMGB1 expression was confined in the nuclei in healthy dental pulp. The mRNA expression of HMGB1 and RAGE were significantly increased in inflamed pulps. In in vitro cultured DPCs, expression of HMGB1 in both protein and mRNA level was up-regulated after treated with lipopolysaccharide (LPS). Exogenous HMGB1 enhanced DPCs migration in a dose-dependent manner and induced the reorganization of f-actin in DPCs. Our results suggests that HMGB1 are not only involved in the process of dental pulp inflammation, but also play an important role in the recruitment of dental pulp stem cells, promoting pulp repair and regeneration

  3. Expression of high mobility group box 1 in inflamed dental pulp and its chemotactic effect on dental pulp cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xufang, E-mail: xufang.zhang@student.qut.edu.au [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4059 (Australia); Jiang, Hongwei, E-mail: jianghw@163.com [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Gong, Qimei, E-mail: gongqmei@gmail.com [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Fan, Chen, E-mail: c3.fan@student.qut.edu.au [Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD 4059 (Australia); Huang, Yihua, E-mail: enu0701@163.com [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Ling, Junqi, E-mail: lingjq@mail.sysu.edu.cn [Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Guangdong Province Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China)

    2014-08-08

    Highlights: • HMGB1 translocated from nucleus to cytoplasm during dental pulp inflammation. • HMGB1and its receptor RAGE were up-regulated in hDPCs under LPS stimulation. • HMGB1 enhanced hDPCs migration and induces cytoskeleton reorganization. • HMGB1 may play a critical role in dental pulp repair during inflamed state. - Abstract: High mobility group box 1 protein (HMGB1) is a chromatin protein which can be released extracellularly, eliciting a pro-inflammatory response and promoting tissue repair process. This study aimed to examine the expression and distribution of HMGB1 and its receptor RAGE in inflamed dental pulp tissues, and to assess its effects on proliferation, migration and cytoskeleton of cultured human dental pulp cells (DPCs). Our data demonstrated that cytoplasmic expression of HMGB1 was observed in inflamed pulp tissues, while HMGB1 expression was confined in the nuclei in healthy dental pulp. The mRNA expression of HMGB1 and RAGE were significantly increased in inflamed pulps. In in vitro cultured DPCs, expression of HMGB1 in both protein and mRNA level was up-regulated after treated with lipopolysaccharide (LPS). Exogenous HMGB1 enhanced DPCs migration in a dose-dependent manner and induced the reorganization of f-actin in DPCs. Our results suggests that HMGB1 are not only involved in the process of dental pulp inflammation, but also play an important role in the recruitment of dental pulp stem cells, promoting pulp repair and regeneration.

  4. OPTIMASI BIOKRAFT JAMUR Phanerochaete chrysosporium TERHADAP KOMPONEN KIMIA CAMPURAN BATANG DAN LIMBAH CABANG MANGIUM SEBAGAI BAHAN BAKU PULP

    Directory of Open Access Journals (Sweden)

    Devi Silsia

    2010-11-01

    Full Text Available Optimation biokraft of fungi P. Chrysosporium through elongated incubation time on mixed stem and branch waste mangium is a solution to solve the environmental pollution problem, low quality of pulp and limited raw material. Effect of P. Chrysosporium 10 % concentration and 45 days incubation time on pre research could not decrease lignin optimally and exstractive degradation had not occured yet. The aims of the study were to observe the effect of incubation time extension, and to determine the best incubation time of P. Chrysosporium applied at 10 % concentration based on the chemical component percentage, 45, 60 and 75 days on mixed stem and branch as raw material for pulp. Results showed that increasing incubation time decreased extractive and lignin content and increased holocelulosa and alpha celulosa content. Mixed stem and branch with 10% amount and 75 day incubation time of P. Chrysosporium gave the best results for raw material of pulp.

  5. Development of a mixed drink made from hydrosoluble soybean extract, coconut water and umbu pulp (Spondias tuberosa

    Directory of Open Access Journals (Sweden)

    Luís Gomes de Moura Neto

    2016-06-01

    Full Text Available The food sector depends on consumers and their social behavior. Since currently more and more consumers seek healthy products, exotic fruits have been increasingly on demand, with great opportunities for innovation. Current study developed a ready-to-drink mixed beverage made from hydrosoluble soybean extract, coconut water and umbu pulp. Four formulations were prepared with two proportions of umbu pulp (25 and 30% and soluble solids (17 and 25º Brix. Formulations were submitted to chemical, physicochemical, microbiological and sensory analyses. The beverage was prepared with 25% of umbu pulp and the soluble solids were standardized to 25º Brix with commercial sugar for the highest scores in sensory attributes, overall impression and purchase intent. The four formulations presented pH, acidity, moisture, total sugar, vitamin C and microbiological results in accordance with current legislation.

  6. Variability analysis of industrial process puree by means of concentrated vegetable pulps, based on the engineering quality.

    Directory of Open Access Journals (Sweden)

    Addys Castellanos Gómez

    2013-03-01

    Full Text Available The instability in quality characteristics: physical-chemical of puree by means of the concentrate plant pulps, can provoke customer dissatisfaction and deterioration of the image of products. With the statistical analysis of the industrial process, was determined as the main cause of erratic behaviour, variability in plant pulps of different suppliers: the different varieties of raw materials and the technologies they used. The solution was established by the quality engineering for improving control and in this case was optimized the product design, consisted on the mixtures of pulps reformulation to ensure initial insensitivity of initial variability that provokes raw material, in this way was achieved the robustness of the process, with positive impact on the production results, both economic and company image to customers.

  7. Hydrothermal carbonization of pulp mill streams.

    Science.gov (United States)

    Wikberg, Hanne; Ohra-Aho, Taina; Honkanen, Mari; Kanerva, Heimo; Harlin, Ali; Vippola, Minnamari; Laine, Christiane

    2016-07-01

    The progress of the conversion, the yield, the structure and the morphology of the produced carbonaceous materials as a function of time were systematically studied with pyrolysis-GC/FID and FESEM microscope. The conversion of galactoglucomannan, bleached kraft pulp and TEMPO oxidized cellulose nanofibrils followed the reaction route of glucose being slower though with fibrous material, higher molar mass and viscosity. The conversion of kraft lignin was minor following completely different reaction route. Carbonaceous particles of different shape and size were produced with yields between 23% and 73% after 4h with being higher for lignin than carbohydrates. According to the results, potential pulp mill streams represent lignocellulosic resources for generation of carbonaceous materials. PMID:27107340

  8. Does removal of the original pulp tissue before autotransplantation influence ingrowth of new tissue in the pulp chamber?

    Science.gov (United States)

    Laureys, Wim G M; Dermaut, Luc R; Cuvelier, Claude A; De Pauw, Guy A M

    2010-10-01

    In an attempt to extend the indication area for autotransplantation of vital teeth, two possibilities can be proposed: (i) The enlargement of the apical foramen, with the aim to facilitate revascularization and ingrowth of new tissue. The ingrowth of tissue will eliminate the need for endodontic treatment when mature teeth are transplanted and (ii) the cryopreservation of teeth in case they cannot be transplanted immediately to the receptor site. Teeth with an ideal stage of root formation can be cryopreserved to perform transplantation later. Although pulpcell cultures survive crypreservation in vitro, the pulp tissue cannot survive the cryopreservation procedures when it is kept inside the pulpchamber. Therefore, the pulp tissue has to be removed before cryopreservation. It has been demonstrated that revascularization and ingrowth of new tissue can occur in an empty pulp chamber (1). The aim of this study was to find out if revascularization and ingrowth of new pulp tissue is influenced by removal of the original pulp tissue before autotransplantation. Twenty nine single-rooted teeth from three adult beagle dogs were transplanted after resection of the root tip. One group of teeth (n = 14) had the pulp tissue removed before transplantation. The other group (n = 15) had the original pulp left in situ. The transplanted teeth were histologically analysed 90 days post-transplantation. In the group with the tissue left in situ, 12 teeth (80%) showed a pulp chamber totally filled or at least 1/3 to 2/3 filled with viable tissue. In the group with the pulp tissue removed, 11 teeth (79%) had no or little vital tissue in the pulp chamber. The necrotic masses that develop in the original pulp tissue immediately after transplantation are a possible stimulating factor in the repair process of the pulp. As a conclusion, it can be stated that in case of autotransplantation of teeth, it is advisable to leave the pulp tissue in situ to stimulate the revascularization and

  9. ISOTHERMAL PYROLYSIS OF KRAFT PULP MILL SLUDGE

    OpenAIRE

    Syamsudin Syamsudin; Herri Susanto; Subagjo Subagjo

    2014-01-01

    Kraft pulp mill sludge cake composed of rejected wood fibers and activated sludge microorganisms. With a heating value about 14 MJ/kg (dried basis), this type of biomass had a potential as an alternative energy source. Unfortunately, it had an ash content of 27.6% and a moisture content of 80%. For reducing moisture content with minimum energy consumption, a combination of mechanical dewatering and thermal drying was studied previously. Meanwhile, experiments on isothermal pyrolysis had been ...

  10. LIGNIN ADSORPTION AND KAPPA NUMBER IN ETHANOL PULPING

    Institute of Scientific and Technical Information of China (English)

    YongjianXu; XinpingLi; MeiyunZhang

    2004-01-01

    The effect of washing temperature, washing stagesand the cooking operation on the ethanol pulp hadbeen investigated, and the reason for higher kappanumber of the ethanol pulp was discussed. Theresults preliminarily showed that the dissolved lignincould re-adsorb to fiber surface by means of fiberclassification technology and explained the questionsfound during the study. Some measures were taken toreduce the kappa number, the results had shown thatthere was obvious absorption in the ethanol pulping;lignin remained in the pulp could easily be dissolvedand the pulp with lower kappa number could beobtained at a higher temperature; the kappa numbercould reduce by increasing washing time; it couldenable dissolved lignin to separate out fi'om theethanol pulp and restrain the lignin absorption byblowing cooking liquid at high temperature.

  11. Pulp moulding machines for the production of packing paper elements

    Directory of Open Access Journals (Sweden)

    Lukić Ljubomir S.

    2005-01-01

    Full Text Available Paper pulp molds are now commonly applied in the technology of modern packing for a wide range of products. The technological process of producing the paper molds has three basic phases: paper pulp preparation, in which water and waste paper are the basic raw materials, the formation of product in tool pulp moulding machines and process drying. The firm "SERVOTEH" from Belgrade has developed various pulp moulding machines for different operating conditions (manual, semiautomatic and automatic operation, different manufacturing capacities and an alternative number of tools. The system of "SERVOTEH" pulp moulding machines covers several construction solutions: a sinking system, veer system and rotation system. This paper presents the technological process, as well as the integral and concept approach to the design of pulp moulding machines and system tools.

  12. LIGNIN ADSORPTION AND KAPPA NUMBER IN ETHANOL PULPING

    Institute of Scientific and Technical Information of China (English)

    Yongjian Xu; Xinping Li; Meiyun Zhang

    2004-01-01

    The effect of washing temperature, washing stages and the cooking operation on the ethanol pulp had been investigated, and the reason for higher kappa number of the ethanol pulp was discussed. The results preliminarily showed that the dissolved lignin could re-adsorb to fiber surface by means of fiber classification technology and explained the questions found during the study. Some measures were taken to reduce the kappa number, the results had shown that there was obvious absorption in the ethanol pulping;lignin remained in the pulp could easily be dissolved and the pulp with lower kappa number could be obtained at a higher temperature; the kappa number could reduce by increasing washing time; it could enable dissolved lignin to separate out from the ethanol pulp and restrain the lignin absorption by blowing cooking liquid at high temperature.

  13. Acid hydrolysis of cellulosic fibres: Comparison of bleached kraft pulp, dissolving pulps and cotton textile cellulose.

    Science.gov (United States)

    Palme, Anna; Theliander, Hans; Brelid, Harald

    2016-01-20

    The behaviour of different cellulosic fibres during acid hydrolysis has been investigated and the levelling-off degree of polymerisation (LODP) has been determined. The study included a bleached kraft pulp (both never-dried and once-dried) and two dissolving pulps (once-dried). Additionally, cotton cellulose from new cotton sheets and sheets discarded after long-time use was studied. Experimental results from the investigation, together with results found in literature, imply that ultrastructural differences between different fibres affect their susceptibility towards acid hydrolysis. Drying of a bleached kraft pulp was found to enhance the rate of acid hydrolysis and also result in a decrease in LODP. This implies that the susceptibility of cellulosic fibres towards acid hydrolysis is affected by drying-induced stresses in the cellulose chains. In cotton cellulose, it was found that use and laundering gave a substantial loss in the degree of polymerisation (DP), but that the LODP was only marginally affected. PMID:26572472

  14. APPLIED STUDY OF BIRCH PULP BLEACHING USING DIMETHYLDIOXIRANE TO OBTAIN ACETATE-GRADE PULP

    Directory of Open Access Journals (Sweden)

    Shu-Ke Zhou

    2010-06-01

    Full Text Available As a pulp bleaching agent, dimethyldioxirane (DMD is effective and selective. In this study, it was employed as a delignifying agent or as an activating agent for hydrogen peroxide treatment in bleaching acetate-grade pulp. Brightness, kappa number, degree of polymerization (DP, and alpha-cellulose content were evaluated to determine the optimal charges of DMD: 2.5% AO, and 4% HSO5-, respectively. Results from the totally chlorine-free (TCF sequences MEQMPA, MEpQMPA, and OQMPA suggested that DMD is both effective and selective as a delignifying agent but not as a brightening agent as compared to oxygen. And in a long sequence for the bleaching of dissolving pulp, acid treatment can be used in two approaches: to remove the metal ions without washing before the chelation stage, and to reduce hemicellulose and ash in the final stage.

  15. Pulp and paper from oil palm fronds: Wavelet neural networks modeling of soda-ethanol pulping

    Directory of Open Access Journals (Sweden)

    Zarita Zainuddin

    2012-11-01

    Full Text Available Wavelet neural networks (WNNs were used to investigate the influence of operational variables in the soda-ethanol pulping of oil palm fronds (viz. NaOH concentration (10-30%, ethanol concentration (15-75%, cooking temperature (150-190 ºC, and time (60-180 min on the resulting pulp and paper properties (viz. screened yield, kappa number, tensile index, and tear index. Performance assessments demonstrated the predictive capability of WNNs, in that the experimental results of the dependent variables with error less than 6% were reproduced, while satisfactory R-squared values were obtained. It thus corroborated the good fit of the WNNs model for simulating the soda-ethanol pulping process for oil palm fronds.

  16. Characterisation of mechanical pulp fines from alkaline peroxide pulping of EFB

    Science.gov (United States)

    Kamaludin, Nurul Hasanah; Ghazali, Arniza; Daud, Wan Rosli Wan

    2012-09-01

    EFB (empty fruit bunch) was subjected to alkaline peroxide pulping for generation of fibrous mass as raw material for the making of pulp-based products. During refining, co-produced fines were collected by fractionation on square-mesh screens of 200-, 250-, 300- and 400- mesh sizes, placed at the refining discharge by order of increasing mesh. Each set of the produced paper was incorporated with 12% fines for microscopic analysis. It appears that sheared vessel elements and fibrils were predominant and they make up the mass rendering collapsibility of cell wall for good product formation. The study acknowledged the form of fines functioning as natural filler in pulp network and worthy of utilization for reduction of total suspended solid.

  17. Rat as a model for direct pulp capping research

    OpenAIRE

    Orhan, Ekim Onur

    2013-01-01

    The aim of this review is to evaluate the suitability of rat teeth in preclinical evaluation of medical materials for direct pulp capping. The international standard states clearly that only non-rodent mammals are suitable species for animal research in dentistry. However, in the past halve of the century many research have been published using rat teeth in order to evaluate direct pulp capping, pulpotomies and tissue reactions after pulp exposure. Numerous studies showed that the healing of ...

  18. Cellulose Depolymerisation and Paper Properties in E. Globulus Kraft Pulps

    OpenAIRE

    Carvalho, M. G.; Ferreira, P. J.; Figueiredo, M.M.

    2000-01-01

    The aim of this work was to study the impact of cellulose depolymerisation on the beating potential and handsheet properties of the portuguese E. globulus kraft pulp. A homogeneous sample of eucalypt wood chips was cooked using different kraft pulping conditions (cooking temperatures and times, and sodium hydroxide and sodium sulphide concentrations) in order to obtain a wide variation for intrinsic viscosity of the pulps. In the range of industrial cooking conditions, this property was found...

  19. [Pulp protectors and the deep regions of the cavity].

    Science.gov (United States)

    Vannier, R

    1984-01-01

    Increasing emphasis is being placed on the use of agents for protection of the pulp and the deep regions of the pulp cavity, modern conservative dentistry attempting as far as possible to conserve pulp vitality. The aim of this report is to assist the dental practitioner in his choice of the different varnishes and cements marketed by dental product manufacturers, to ensure the maximum of benefits for patients' teeth. PMID:6588464

  20. Characterisation of a phenolic resin and sugar cane pulp composite

    OpenAIRE

    Leite, J.L.; A. T. N. Pires; S. M. A. G. Ulson de Souza; A.A.Ulson de Souza

    2004-01-01

    Polymeric materials are increasingly replacing metallic materials as a result of their properties. In this work a composite of phenolic resin and sugar cane pulp was developed. The sugar cane pulp has been previously alkalinised, dried, and milled and the particles had been classified in a range of grain sizes. Experimental assays were performed, varying the proportion of the resin and the reinforcement and the size of the cane pulp fibre, keeping the pressure and moulding temperature constan...

  1. IMPACT OF COOKING HOMOGENEITY ON PULP STRENGTH PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    Bofeng Mao

    2004-01-01

    Cooking homogeneity of kraft pulping can have significant impact on pulp strength properties. We have studied cooking homogeneity of two kraft digesters within Stora Enso. One of the digesters is a one-vessel hydraulic continuous digester (digester A)and the other one is a two-vessel vapor/liquor phase continuous digester (digester B). They are located in the same mill and use the same softwood chip quality. Due to the differences in chip pre-steaming and cooking facilities and conditions, significant differences in pulp strength properties, reject contents and kappa variations have been found between the pulps produced in the two digesters. Digester A has a modem chip bin with efficient pre-heating and air removal, whereas digester B has poor chip pre-steaming conditions. Our strength delivery studies show that although the two digesters produce pulps with the same kappa number and viscosity, the pulp produced in digester A has about 20% higher strength delivery, l%-unit (based on wood) lower reject content and lower kappa variations based on FTIR spectra analysis on pulp sheet than the pulp produced in digester B.Results of the studies indicate that more homogeneous cooking, i.e., lower lignin/kappa variation in the fibers, leads to improved pulp strength properties. Efficient chip pre-steaming is important/essential for achieving homogeneous cooking. Rebuilding the equipment for improving chip pre-steaming conditions of digester B is to be carried out.

  2. LPS induces pulp progenitor cell recruitment via complement activation.

    Science.gov (United States)

    Chmilewsky, F; Jeanneau, C; Laurent, P; About, I

    2015-01-01

    Complement system, a major component of the natural immunity, has been recently identified as an important mediator of the dentin-pulp regeneration process through STRO-1 pulp cell recruitment by the C5a active fragment. Moreover, it has been shown recently that under stimulation with lipoteichoic acid, a complex component of the Gram-positive bacteria cell wall, human pulp fibroblasts are able to synthesize all proteins required for complement activation. However, Gram-negative bacteria, which are also involved in tooth decay, are known as powerful activators of complement system and inflammation. Here, we investigated the role of Gram-negative bacteria-induced complement activation on the pulp progenitor cell recruitment using lipopolysaccharide (LPS), a major component of all Gram-negative bacteria. Our results show that incubating pulp fibroblasts with LPS induced membrane attack complex formation and C5a release in serum-free fibroblast cultures. The produced C5a binds to the pulp progenitor cells' membrane and induces their migration toward the LPS stimulation chamber, as revealed by the dynamic transwell migration assays. The inhibition of this migration by the C5aR-specific antagonist W54011 indicates that the pulp progenitor migration is mediated by the interaction between C5a and C5aR. Our findings demonstrate, for the first time, a direct interaction between the recruitment of progenitor pulp cells and the activation of complement system generated by pulp fibroblast stimulation with LPS. PMID:25359783

  3. Production of furans from pulp sheet over sulfated solid acid catalysts

    Directory of Open Access Journals (Sweden)

    Hongdan Zhang

    2012-11-01

    Full Text Available Furans are high value-added biomass-derived chemicals that can be used to replace petrochemicals. In this study, sulfated solid acid catalysts were prepared by precipitation and impregnation and were used for the conversion of a cellulosic pulp sheet into furans. The physicochemical properties of the prepared sulfated solid acid with different calcination temperatures and different mol ratios of Ti-Al were characterized using XRD, elemental analysis, TG, and NH3-TPD. Furthermore, the effects of various processing parameters such as temperature, time, and catalyst dosage on the reaction performance were studied. The combined yield of 5-hydroxymethyl-furfural and furfural reached 8.9% and 4.5% of pulp sheet mass with a 5% dosage of SO42-/TiO2-Al2O3 catalyst at 220 oC for 30 min. The activity for recovered catalyst was also investigated in this study.

  4. Conservation of jucara pulp (Euterpe edulis) submitted to gamma radiation, pasteurization, lyophilization and spray drying

    International Nuclear Information System (INIS)

    In Brazil there are unexplored fruit species, which represent an opportunity for producers to access special markets, where consumers appreciate the exotic character and presence of nutrients capable of preventing degenerative diseases. In this context, jucara palm (Euterpe edulis), native of the Atlantic Forest, has long been explored only for the removal of the stem, but currently the pulp of its fruit is becoming more popular. The intense purple color is due to the presence of anthocyanins, powerful antioxidants that act by inhibiting or decreasing the effects unleashed by free radicals. The pulp is highly perishable and its preservation is impossible at room temperature, lowering its market value in sales. In face of this, we need technologies that minimize nutritional and sensorial losses in order to produce healthy, tasty and long lasting foods. This study consists of five experiments with jucara pulp, which aimed to: evaluate the physico-chemical, mineral and lipid composition; realize the sensory characterization by Quantitative Descriptive Analysis (QDA); evaluate the physico-chemical and sensory conservation when submitted to radiation gamma, acidification and pasteurization, and dehydration by spray and freeze drying. The fruits have been obtained at Parque das Neblinas (Mogi das Cruzes/SP) and depulped at Agribusiness, Food and Nutrition Department (ESALQ/USP). Was verified that jucara pulp is excellent source of energy and minerals K, Fe, Co, Mg, Cu, Zn, Mn and Mo; rich in anthocyanins and fatty oils of good quality (palmitic, oleic and linoleic). The irradiation of pulp was performed at the Institute of Energy and Nuclear Research (IPEN - Sao Paulo, SP) at doses 0,0, 2,5, 5,0, 7,5 and 10,0 kGy and stored at 6 degree C for 30 days (fortnightly assessments). That process was not promising for the conservation of the product at 6 degree C, because the degradation of anthocyanins and phenolic compounds was accelerated and the color changed from purple to

  5. Effect of raw material and Kraft Pulping Conditions on Characteristics of Dissolved Lignin

    OpenAIRE

    Svärd, Antonia

    2014-01-01

    Lignin is one of the main components in wood and during the chemical pulping processes it is degraded and dissolved into the cooking liquor. The current challenge is to meet the need for energy and raw materials, and reform to a more environmentally sustainable society, so there is a great interest in using kraft lignin as a raw material for energy, materials and as source of chemicals. ) To meet this goal, it is essential to obtain kraft lignin with desirable properties. The overall goal of ...

  6. Pemanfaatan Limbah Pulp Buah Semangka (Citrullus vulgaris, Schard) Untuk Pembuatan Nata De Watermelon Pulp Dengan Menggunakan Bakteri Acetobacter xylinum

    OpenAIRE

    Mawaddah

    2011-01-01

    This research done to know can or not the waste of watermelon pulp use to produce nata and how the effect of mass variation using to nata’s quality. This research was done with mass variation of watermelon pulp that is 10 g, 20 g, 30 g, 40 g, 50 g, 60 g, and watermelon pulp without adding sugar as control. Statistical analysis count the thickness, water content, ash content, fiber content and organoleptic test of texture, color, aroma, and taste of nata de watermelon pulp. The result show...

  7. EVALUATION OF PULP AND PAPER MAKING CHARACTERISTICS OF RICE STEM FIBERS PREPARED BY TWIN-SCREW EXTRUDER PULPING

    OpenAIRE

    Alireza Talebizadeh; Pejman Rezayati-Charani

    2010-01-01

    Twin-screw extrusion pulping is a new approach to the manufacture of pulp for paper production, designed for non-wood feedstocks. In this research, the production of pulp from rice stem with a newly fabricated twin-screw extruder was investigated. Extrusion pulping of rice stem was conducted following a central composite design using a two-level factorial plan involving three process variables (pretreatment NaOH concentration: 0.4, 0.8, 1.2%; extrusion temperature: 40, 60, 80 oC; and extruder...

  8. PRESENCE OF HARDWOOD CHIPS AND ITS IMPACT ON PULP STRENGTH PROPERTIES IN THE PRODUCTION OF BLEACHED SOFTWOOD KRAFT PULP

    Directory of Open Access Journals (Sweden)

    Zhibin He

    2010-11-01

    Full Text Available The effect of hardwood admixture (15-25% birch or aspen in kraft cooking on the strength properties of the fully bleached pulp was investigated. Results obtained from both lab- and mill-processed ECF bleached pulps showed that adding 15-25% birch or aspen to the production of fully bleached softwood kraft pulp had a minor effect on the strength properties. No significant effect was observed for the hardwood admixture on the apparent density over a wide range of breaking length. Under the conditions studied, the results showed that pulping of mixed softwood/hardwood chips (chip blending resulted in overall better strength properties than the pulp blending at a given freeness. It was hypothesized that the softwood fibers would be cooked to a higher kappa number in the cooking of mixed softwood/hardwood chips for the same target kappa number, thus having higher fiber strength due to higher pulp viscosity and preservation of the hemicellulose. This was supported by the results from zero-span tensile strength of the long fiber fraction of the samples from chip blending and pulp blending. The implication is that some softwood kraft pulp mills can add up to 25% of hardwood chips to the kraft cooking of softwood chips without significantly affecting the overall pulp strength properties.

  9. Studies of chemical and enzymatic characteristics of Yacon (Smallanthus sonchifolius) and its flours Estudo das carcaterísticas químicas e enzimáticas de Yacon (Smallanthus sonchifolius) e suas farinhas

    OpenAIRE

    Juciane de Abreu Ribeiro Pereira; Maria de Fátima Píccolo Barcelos; Michel Cardoso de Angelis Pereira; Eric Batista Ferreira

    2013-01-01

    Due to the importance of studies on yacon related to health, its in natura pulp, in natura peel, pulp flour, and peel flour were chemically analyzed in terms of its centesimal composition, specific minerals, total dietary fiber and fractions, pH, total soluble solids, total titratable acidity, tannins, oxalic acid, and nitrate. The polyphenoloxidase and peroxidase enzymatic activities were evaluated for in natura pulp and peel only. Yacon pulp and peel flour presented average yield of 7.94% a...

  10. 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

  11. SPMDs accumulate fish MFO inducers from pulp mills and oil refineries

    International Nuclear Information System (INIS)

    Semipermeable Membrane Devices (SPMDs) deployed for 14 d in waters of the Athabasca River and in effluents from four pulp mills and one oil refinery accumulated chemicals that induced mixed-function oxygenase (MFO) in a fish cell line. To express the potency of SPMD extracts, dose-response curves for EROD induction in coils exposed to SPMD-extracts were compared to dose-response curves for 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Extracts of SPMDs from pulp mills were two to five times as potent as extracts of SPMDs exposed to background river water. SPMD extracts from three pulp mill effluents had 62.0, 53.5, and 29.7 pg TCDD-EQ/g, significantly more than in Athabasca River water (12.6 pg TCDD-EQ/g = background). SPMDs exposed to effluent from a fourth mill had potencies within the 95% confidence interval of background. The concentrations of MFO inducers in SPMDs exposed to river water increased downstream of Fort McMurray (58.5 to 728 pg TCDD-EQ/g) and SPMDs deployed in effluent from the oil refinery accumulated the most MFO-inducing chemicals (16,800 pg TCDD-EQ/g). SPMD accumulation was highly variable, which suggested an unknown source of inducers, possibly an effluent from the town or input from natural erosion of the tar sands. Although this study was preliminary, the results suggest the four pulp mill effluents contribute small quantities of MFO inducers to the Athabasca River. By contrast, very high quantities of MFO inducers were discharged by oil refinery effluent

  12. Activity-guided identification of acetogenins as novel lipophilic antioxidants present in avocado pulp (Persea americana).

    Science.gov (United States)

    Rodríguez-Sánchez, Dariana; Silva-Platas, Christian; Rojo, Rocío P; García, Noemí; Cisneros-Zevallos, Luis; García-Rivas, Gerardo; Hernández-Brenes, Carmen

    2013-12-30

    Avocado fruit is a rich source of health-related lipophilic phytochemicals such as monounsaturated fatty acids, tocopherols, carotenes, acetogenins and sterols. However, limited information is available on the contribution of specific phytochemicals to the overall antioxidant capacity (AOC) of the fruit. Centrifugal partition chromatography was used as fractionation tool, guided by an in vitro chemical assay of oxygen radical absorbance capacity (ORAC). Subsequent experiments focused on isolation and characterization of the chemical nature of the main contributors to lipophilic AOC of avocado pulp. ORAC values obtained for acetogenins were contrasted with results from an isolated kidney mitochondria membrane lipid peroxidation bioassay. The present study established that lipophilic AOC of the pulp was significantly higher than its hydrophilic AOC. Our results confirmed the presence of acetogenins in the fractions with highest lipophilic AOC, and for the first time linked them as contributors to lipophilic-ORAC values. Further HPLC-PDA/MS-TOF analysis led to structural elucidation of two novel acetogenins, not previously reported as present in avocado pulp, along with five already known related-compounds. Antioxidant properties observed for avocado pulp acetogenins by the ORAC assay suggested that, in the presence of an emulsifying agent, acetogenins could serve as novel lipophilic antioxidants in a food matrix. Results from isolated mitochondria lipid peroxidation bioassay, indicated that L-ORAC values which may have relevance for food matrix applications, should not be interpreted to have a direct relevance in health-related claims, compounds need to be evaluated considering the complexity of biological systems. PMID:24211333

  13. Histological effects of enamel matrix derivative on exposed dental pulp

    Directory of Open Access Journals (Sweden)

    Popović-Bajić Marijana

    2015-01-01

    Full Text Available Introduction. Direct pulp capping procedure is a therapeutic application of a drug on exposed tooth pulp in order to ensure the closure of the pulp chamber and to allow the healing process to take place. Objective. The aim of this study was to examine the histological effects of Emdogain® on exposed tooth pulp of a Vietnamese pig (Sus scrofa verus. Methods. The study comprised 20 teeth of a Vietnamese pig. After class V preparation on the buccal surfaces of incisors, canines and first premolars, pulp was exposed. In the experimental group, the perforations were capped with Emdogain® (Straumann, Basel, Switzerland, while in the control group pulp capping was performed with MTA® (Dentsply Tulsa Dental, Johnson City, TN, USA. All cavities were restored with glass-ionomer cement (GC Fuji VIII, GC Corporation, Tokyo, Japan. The observational period was 28 days, after which the animal was sacrificed and histological preparations were made. A light microscope was used to analyze dentin bridge formation, tissue reorganization and inflammation, and the presence of bacteria in the pulp. Results. The formation of dentin bridge was observed in the experimental and control groups. Inflammation of the pulp was mild to moderate in both groups. Angiogenesis and many odontoblast-like cells, responsible for dentin bridge formation, were observed. Necrosis was not observed in any case, nor were bacteria present in the pulp. Conclusion. Histological analysis indicated a favorable therapeutic effect of Emdogain® Gel in direct pulp capping of Vietnamese pigs. Pulp reaction was similar to that of MTA®. [Projekat Ministarstva nauke Republike Srbije, br. ON172026

  14. Feasibility of recovery boiler in paper and pulp industry

    International Nuclear Information System (INIS)

    in this paper feasibility of recovery boiler in terms of economics and environmental impacts in studied. Recovery boilers are employed in the pulp and paper industry where the cooking agent is recovered by burning black liquor. Cooking agent is exhausted due to the absorption of lignin (a burnable component) in cooking agent in the process of straw cooking. The process of recovery boiler is to remove lignin by combustion from black liquor, and heat is produced during the combustion of lignin which is used to produce steam. Recovery boiler is economical as it is recovering valuable chemicals and steam is produced as a byproduct. Steam from recovery boiler is also used for concentrating weak black liquor to concentrated black liquor recovering 50% of the utility water being used at the plant. The regenerated water in the form of foul condensate is reused in the process. The recovery of hazardous chemicals also reduces load of environmental pollution. Which otherwise can pollute the water reservoirs, and regeneration of water makes it environmentally friendly plant. Construction and challenges in operation of recovery boiler such as smelt-water explosion are also discussed in this paper. (author)

  15. Sequenced anaerobic-aerobic treatment of hemp pulping wastewaters.

    NARCIS (Netherlands)

    Kortekaas, S.

    1998-01-01

    Biological treatment is an indispensable instrument for water management of non-wood pulp mills, either as internal measure to enable progressive closure of water cycles, or as end of pipe treatment. In this thesis, the sequenced anaerobic-aerobic treatment of hemp ( Cannabis sativa L. ) pulping was

  16. Homo-hetero-phono-graphy: on Quentin Tarantino's _Pulp Fiction_

    OpenAIRE

    Dutoit, Thomas

    2008-01-01

    Quentin Tarantino's film _Pulp Fiction_ (1994) depicts ostensible males unsettled by desires for trans-sexuality or trans-sexualization as désire. _Pulp Fiction_ turns sexual identity into sexual otherness and something other than sexuality through a host of props, devices and linguistic transfers that set deconstructed sexual différence into motion pictures.

  17. Potential for biohydrogen and methane production from olive pulp

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Skiadas, Ioannis V.; Ahring, Birgitte Kiær;

    2005-01-01

    The present study investigates the potential for thermophilic biohydrogen and methane production from olive pulp, which is the semi-solid residue coming from the two-phase processing of olives. It focussed on: a) production of methane from the raw olive pulp, b) anaerobic bio-production of hydrogen...

  18. Hydrothermal treatment and ethanol pulping of sunflower stalks.

    Science.gov (United States)

    Caparrós, S; Ariza, J; López, F; Nacimiento, J A; Garrote, G; Jiménez, L

    2008-03-01

    The influence of temperature in the hydrothermal treatment of sunflower stalks on the composition of the liquid fraction obtained was examined. The remaining solid fraction was subjected to ethanol pulping in order to obtain pulp that was used to produce paper sheets. The pulp was characterized in terms of yield, kappa index, viscosity, and cellulose, hemicellulose and lignin contents; and the paper sheets in terms of breaking length, stretch, burst index and tear index. Hydrothermal treatment of the raw material at 190 degrees C provided a liquid phase with maximal hemicellulose-derived oligomers and monosaccharide (glucose, xylose and arabinose) contents (26.9 and 4.2 g/L, respectively). Pulping the solid fraction obtained by hydrothermal treatment at 180 degrees C, with 70% ethanol at a liquid/solid ratio of 8:1 at 170 degrees C for 120 min provided pulp with properties on a par with those of soda pulp from the sunflower stalks, namely: 36.3% yield, 69.1% cellulose, 12.6% hemicellulose, 18.2% lignin and 551 ml/g viscosity. Also, paper sheets obtained from the ethanol pulp were similar in breaking length (3.8 km), stretch (1.23%), burst index (1.15 kN/g) and tear index (2.04 m Nm(2)/g) to those provided by soda pulp. PMID:17369038

  19. Biota: sediment partitioning of aluminium smelter related PAHs and pulp mill related diterpenes by intertidal clams at Kitimat, British Columbia.

    Science.gov (United States)

    Yunker, Mark B; Lachmuth, Cara L; Cretney, Walter J; Fowler, Brian R; Dangerfield, Neil; White, Linda; Ross, Peter S

    2011-09-01

    terpenes that form the chemical defence mechanism of conifers) released by pulp mills are bioavailable and possess demonstrated toxic properties. The large scale release of plant terpenes by some of the many pulp mills located in British Columbia and elsewhere represents a largely undocumented risk to aquatic biota. PMID:21788067

  20. Biodentine pulpotomy several days after pulp exposure: Four case reports

    Directory of Open Access Journals (Sweden)

    Swati A Borkar

    2015-01-01

    Full Text Available Conventionally, few-days-old pulp exposures have been treated with root canal treatment. We report four cases of traumatized, fully matured, maxillary permanent central incisors, which have been treated by Biodentine pulpotomy several days after traumatic pulp exposure. Biodentine pulpotomy consisted of pulp tissue removal to a depth of 2 mm, then capping the pulpal wound with Biodentine, followed by immediate restoration. The teeth were assessed clinically through pulpal sensitivity tests and radiographically for periapical healing. At each recall (24 hours, 1 week, 30 days, 3, 6, 12, and 18 months, no spontaneous pain was observed; the pulp showed signs of vitality and absence of periapical radiolucency after 18 months. Biodentine pulpotomy is recommended as a treatment option for cases of vital pulp exposure in permanent incisors due to trauma.

  1. Biodentine pulpotomy several days after pulp exposure: Four case reports

    Science.gov (United States)

    Borkar, Swati A.; Ataide, Ida

    2015-01-01

    Conventionally, few-days-old pulp exposures have been treated with root canal treatment. We report four cases of traumatized, fully matured, maxillary permanent central incisors, which have been treated by Biodentine pulpotomy several days after traumatic pulp exposure. Biodentine pulpotomy consisted of pulp tissue removal to a depth of 2 mm, then capping the pulpal wound with Biodentine, followed by immediate restoration. The teeth were assessed clinically through pulpal sensitivity tests and radiographically for periapical healing. At each recall (24 hours, 1 week, 30 days, 3, 6, 12, and 18 months), no spontaneous pain was observed; the pulp showed signs of vitality and absence of periapical radiolucency after 18 months. Biodentine pulpotomy is recommended as a treatment option for cases of vital pulp exposure in permanent incisors due to trauma. PMID:25657533

  2. Cytotoxicity and biocompatibility of direct and indirect pulp capping materials

    Directory of Open Access Journals (Sweden)

    Karin Cristina da Silva Modena

    2009-12-01

    Full Text Available There are several studies about the cytotoxic effects of dental materials in contact with the pulp tissue, such as calcium hydroxide (CH, adhesive systems, resin composite and glass ionomer cements. The aim of this review article was to summarize and discuss the cytotoxicity and biocompatibility of materials used for protection of the dentin-pulp complex, some components of resin composites and adhesive systems when placed in direct or indirect contact with the pulp tissue. A large number of dental materials present cytotoxic effects when applied close or directly to the pulp, and the only material that seems to stimulate early pulp repair and dentin hard tissue barrier formation is CH.

  3. Holdup time measurement by radioactive tracers in pulp production

    International Nuclear Information System (INIS)

    A batch of pulp was to be labelled before passing two bleaching towers of a pulp plant. Activated glass fibres were used as a tracer, which contained 24-Na with a half-life of 15 hours. It was shown in laboratory tests, that the glass fibres were suitable for transport studies of wood pulp. For use in the tests the fibres were activated and suspended in water. Due to the small diameter of the fibres (2-5 micrometers) this suspension shows physical properties very similar to the pulp. For detection six scintillation probes were mounted at different positions outside the bleaching tower. Radiation protection during the test was very easy due to the low total activity of the tracer material. Residence time distributions for both towers were measured. The successful tracer experiments show, that the method of labelling is suited for investigations of material transport in the pulp and paper industry. 3 figs., 11 refs., 2 tabs. (Author)

  4. STEAM EXPLOSION PULPING OF OIL PALM EMPTY FRUIT BUNCH FIBER

    Directory of Open Access Journals (Sweden)

    Xiwen Wang,

    2012-01-01

    Full Text Available Steam explosion pulping was evaluated for oil palm empty fruit bunches fiber. The fiber morphology was observed by SEM and TEM. Results indicated that lignin was molten and the cell wall damaged after the steam explosion pulping and that the fiber was partly separated at the same time. The results of handsheet tests showed that the steam exploded pulp had a high yield (78.2%, good physical properties (especially for ring crush 8.6 N•m/g, and low effluent load (SS=910 mg/L; BOD5=3952 mg/L; CODCr=8140 mg/L. The SEP pulp from oil palm EFB fiber was very suitable for packaging paper when combined with American OCC pulp.

  5. 阔叶木硫酸盐制浆和漂白中应用化学添加剂脱除抽提物%Using Additives for the Removal of Extractives in Kraft Pulping and Bleaching of Hardwood

    Institute of Scientific and Technical Information of China (English)

    胥成龙

    2004-01-01

    The effect of four additives (surfactants and dispersant) that were supplied by Hercules Chemicals Singapore Pte Ltd on kraft pulping and bleaching of Eucalyptus camaldulensis and Acacia mangium has been studied. The use of additives results in a more removal of extractives, and in a more uniform cook with lower screen rejects in eucalyptus, lower residual alkali, and in an improvement in brightness of eucalyptus pulps. At low additive charge level, a reduction of kappa number generated without clear loss of pulp yield in acacia cook.

  6. Can Pulp Fibroblasts Kill Cariogenic Bacteria? Role of Complement Activation.

    Science.gov (United States)

    Jeanneau, C; Rufas, P; Rombouts, C; Giraud, T; Dejou, J; About, I

    2015-12-01

    Complement system activation has been shown to be involved in inflammation and regeneration processes that can be observed within the dental pulp after moderate carious decay. Studies simulating carious injuries in vitro have shown that when human pulp fibroblasts are stimulated by lipoteichoic acid (LTA), they synthetize all complement components. Complement activation leads to the formation of the membrane attack complex (MAC), which is known for its bacterial lytic effect. This work was designed to find out whether human pulp fibroblasts can kill Streptococcus mutans and Streptococcus sanguinis via complement activation. First, histological staining of carious tooth sections showed that the presence of S. mutans correlated with an intense MAC staining. Next, to simulate bacterial infection in vitro, human pulp fibroblasts were incubated in serum-free medium with LTA. Quantification by an enzymatic assay showed a significant increase of MAC formation on bacteria grown in this LTA-conditioned medium. To determine whether the MAC produced by pulp fibroblasts was functional, bacteria sensitivity to LTA-conditioned medium was evaluated using agar well diffusion assay and succinyl dehydrogenase (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide [MTT]) assay. Both assays showed that S. mutans and S. sanguinis were sensitive to LTA-conditioned medium. Finally, to evaluate whether MAC formation on cariogenic bacteria, by pulp fibroblasts, can be directly induced by the presence of these bacteria, a specific coculture model of human pulp fibroblasts and bacteria was developed. Immunofluorescence revealed an intense MAC labeling on bacteria after direct contact with pulp fibroblasts. The observed MAC formation and its lethal effects were significantly reduced when CD59, an inhibitor of MAC formation, was added. Our findings demonstrate that the MAC produced by LTA-stimulated pulp fibroblasts is functional and can kill S. mutans and S. sanguinis. Taken together

  7. Effect of silicon carbide and pulping processes on physical and mechanical properties of pulp plastic composites (PPCs

    Directory of Open Access Journals (Sweden)

    Alireza Sukhtesaraie

    2016-03-01

    Full Text Available This study evaluated the effect of different pulping processes and SiC particles on physical and mechanical properties of pulp plastic composites (PPCs. Polypropylene (PP, SODA and NSSC pulp fibers (max. 40 and 50 wt.%, silicon carbide particles (0, 5, 10, 15 wt.%, and 5 wt.% maleic anhydride polypropylene (MAPP as coupling agent were used to produce pulp plastic composites (PPCs by injection molding. The physical and mechanical properties of samples were characterized according to ASTM standards. SODA pulp composites illustrated higher values in all properties except contact angle and showed approximately same abrasion resistance compared to NSSC pulp composites. The addition of SiC particles improved the negative effect of pulp fibers in water absorption, and increased both contact angle and abrasion resistance of PPCs. By contrast, tensile, flexural, and impact properties of pulp plastic composites decreased by increasing SiC particles. In general, 50 wt.% SODA/SiC composite containing 10 wt.% SiC particles showed the highest efficiency among composites.

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

    Directory of Open Access Journals (Sweden)

    Dharm Dutt

    2010-08-01

    Full Text Available 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 comparison of properties AS-AQ pulping processes with soda and kraft pulping processes of H. cannabinus, C. sativa, and H. sabdariffa was made. All the properties were found to be better than soda and kraft pulps except tear index. All of the mechanical strength properties of handsheets of AS-AQ pulp improved except tear index. Therefore, the AS-AQ pulping process can be considered as ideal for manufacturing of paper grades like greaseproof, glassine, and high-quality writing and printing paper.

  9. Bioactive Phenylpropanoids, Phenolic Acid and Phytosterol from Landolphia owariensis P. Beauv Stringy Seed Pulp.

    Science.gov (United States)

    Okonkwo, Tochukwu J N; Osadebe, Patience O; Proksch, Peter

    2016-01-01

    Landolphia owariensis P. Beauv is economically important for latex/rubber and folklore medicine. Its stringy seed pulp is freely eaten by humans and animals. Thus, L. owariensis stringy seed pulp was extracted serially with hexane and acetone to isolate and characterize its active pharmaceutical ingredients. Solvent/solvent partition and chromatographic separations afforded four bioactive compounds, (E)-3-(3,4-Dihydroxylcinnamoyl)quinic acid [(E)-Chlorogenic acid], I; (E)-3-(3,4-Dihydroxylcinnamoyl)quinic acid methyl ester [(E)-Chlorogenic acid methyl ester], II; 3,4-Dihydroxylbenzoic acid, (Protocatechuic acid), III; and 22,23-Dihydrostigmaster-3β-ol (3β-Sitosterol) (IV). Structures of I, II and III were assigned by combinations of high-performance liquid chromatography-ultraviolet-visible spectroscopy, 1D and 2D nuclear magnetic resonance spectroscopy, high-performance liquid chromatography-mass spectrometry and reference to published literatures, while compound IV was identified by chemical methods and gas chromatography-mass spectrometry. The phenylpropanoids and phenolic acid (compounds I, II and III) are notable standard antioxidants with confirmed hepatic-protective activity and other exciting biological activities. Compound IV has been reported to possess anti-inflammatory activity, anti-colon cancer action and a cholesterol-lowering effect. The described compounds are important medicinal constituents of L. owariensis stringy seed pulp, and this is the first major report on the phytochemistry of L. owariensis P. Beauv. PMID:26537109

  10. Energy use and distribution in the pulp paper and boardmaking industries

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, S. I.

    1977-08-01

    The Pulp, Paper and Boardmaking Industries (PPBI) are major energy consumers in the U.S. economy, ranking fourth among all industry groups in this respect. Including the consumption of waste streams generated within the industry's manufacturing processes, the overall energy consumption in 1972 was 2.2 x 10/sup 15/ Btu (2.2 quads or 2.3 x 10/sup 18/ joules). Energy consumption is almost equally distributed between pulpmaking and recovery or regeneration of pulping chemicals, on the one hand, and pulp drying, papermaking and boardmaking, on the other. The impact of proposed near-term pollution abatement regulations upon the industry's overall energy consumption is expected to be modest, with additional energy use for discharge control to both air and water aggregating less than 5%. Zero Pollution Discharge (ZPD) regulations could nearly double the energy requirements per ton of product however, due mainly to liquid effluent treatment requirements. The energy savings predicted by the industry, assuming that ZPD is not required, is approximately 10% below the 1972 level, per unit of product, by 1980. Full utilization of all industry alternatives for conservation could probably double this savings.

  11. Kinetics of pulp mill effluent treatment by ozone-based processes

    International Nuclear Information System (INIS)

    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.

  12. Color, TOC and AOX removals from pulp mill effluent by advanced oxidation processes: A comparative study

    International Nuclear Information System (INIS)

    Pulp mill effluent containing toxic chemicals was treated by different advanced oxidation processes (AOPs) consisting of treatments by hydrogen peroxide, Fenton's reagent (H2O2/Fe2+), UV, UV/H2O2, photo-Fenton (UV/H2O2/Fe2+), ozonation and peroxone (ozone/H2O2) in laboratory-scale reactors for color, total organic carbon (TOC) and adsorbable organic halogens (AOX) removals from the pulp mill effluent. Effects of some operating parameters such as the initial pH, oxidant and catalyst concentrations on TOC, color, AOX removals were investigated. Almost every method used resulted in some degree of color removal from the pulp mill effluent. However, the Fenton's reagent utilizing H2O2/Fe2+ resulted in the highest color, TOC and AOX removals under acidic conditions when compared with the other AOPs tested. Approximately, 88% TOC, 85% color and 89% AOX removals were obtained by the Fenton's reagent at pH 5 within 30 min. Photo-Fenton process yielded comparable TOC (85%), color (82%) and AOX (93%) removals within 5 min due to oxidations by UV light in addition to the Fenton's reagent. Fast oxidation reactions by the photo-Fenton treatment makes this approach more favorable as compared to the others used

  13. National design environment for pulp mills; Kansallinen paperitehtaan suunnitteluympaeristoe - PMST 03

    Energy Technology Data Exchange (ETDEWEB)

    Kaijaluoto, S. [VTT Energy, Jyvaeskylae (Finland)

    1998-12-31

    The research to be done in the CACTUS research programme produces new process models and generates new knowledge about the influence of various contaminants on the runnability and the quality of paper. The generated information calls for an environment where it can be analysed and utilised. The goal of the project is to build a design environment for papermaking processes. The environment will be composed of a number of tools, all integrated together, that can be used in process design from preliminary concept screening through detailed simulation studies to the design and tuning of control systems. The design environment is based on the Balas and APMS simulation programmes developed at VTT. Balas is a general steady-state simulation package for chemical processes with emphasis on pulp and paper. Recent applications include the analysis of the influence of new drying techniques on the energy and water management of a paper mill and the evaluation of new paper machine and water treatment concepts. APMS (Advanced Pulp and Paper Mill Simulator) is a new flexible tool intended for fast modelling and efficient simulation of the dynamic performance the various unit processes in pulp and paper mill, or even of the whole integrated mill. (orig.)

  14. USING A MEMBRANE FILTRATION PROCESS TO CONCENTRATE THE EFFLUENT FROM ALKALINE PEROXIDE MECHANICAL PULPING PLANTS

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    2010-05-01

    Full Text Available Using a multi-effect evaporation system to concentrate the effluent from alkaline peroxide mechanical pulping (APMP plants is known to require a high energy consumption. In order to improve the situation, a polyethersulfone membrane was used to concentrate the effluent of APMP plants beforehand. An orthogonal experimental design was applied and a mathematical model was established to optimize the filtration parameters. An estimation of potential energy and water savings from this new concentration process was developed. The optimal filtration conditions obtained were: molecular weight cut-off at 10,000 Dalton, trans-membrane pressure at 3 bar, feed temperature at 50oC, cross-flow velocity at 420 rpm, and volume reduction factor at 0.93. The average permeate flux under these conditions was 45.31 l/m2.h. The total solids content was increased from 14.74 g/l in the feed to 95.04 g/l in the concentrate. The permeate had low total solid contents of 8.75 g/l, Chemical Oxygen Demand of 6696 mg/l, and Biochemical Oxygen Demand of 4383 mg/l. Such qualities would allow the permeate to be reused in the alkaline peroxide mechanical pulping process. With this new concentration process, about 4840.6 kwh energy can be saved and 23.3 m3 effluent discharge can be reduced for each ton of pulp produced.

  15. Hygroscopic behavior of lyophilized acerola pulp powder

    Directory of Open Access Journals (Sweden)

    Luciana C. Ribeiro

    2016-03-01

    Full Text Available ABSTRACT Powder products are characterized by their practicality and long life. However, fruit powders have high hygroscopicity and tend to agglomerate due to its hydrophilic nature. The isotherms of equilibrium moisture content apply to the study of dehydrated food preservation potential. Acerola is a nutritionally rich fruit, with great economic and industrial potential. The objective of this study was to analyse acerola powder adsorption isotherms obtained by lyophilization and characterize the powder obtained from lyophilized acerola pulp. Analysis of hygroscopicity, solubility and degree of caking were performed. Isotherms were represented by the mathematical models of GAB, BET, Henderson and Oswin, at temperatures of 25, 35 and 45 °C. According to the results, the obtained powder showed hygroscopicity of 5.96 g of absorbed water 100g-1 of solids, solubility of 95.08% and caking of 14.12%. The BET model showed the best fit to the adsorption isotherms of the acerola pulp powder obtained by lyophilization. The obtained isotherm was of type III, with a "J" shape. There was an inversion of the effect of temperature on the isotherms of acerola powders.

  16. Responses of white sucker (Catostomus commersoni) to 20 years of process and waste treatment changes at a bleached kraft pulp mill, and to mill shutdown.

    Science.gov (United States)

    Bowron, L K; Munkittrick, K R; McMaster, M E; Tetreault, G; Hewitt, L M

    2009-11-01

    The impacts of pulp mill effluents on white sucker (Catostomus commersoni) have been studied at Jackfish Bay, ON, Canada since the late 1980s. The site receives effluent from a large bleached kraft pulp mill which is the only source of chemical contamination in the area. Many laboratory studies have looked at the toxicological consequences of pulping process changes, but the benefit of these changes have not been looked at in wild fish. Jackfish Bay white sucker showed impacts on sexual maturity, gonad size, secondary sexual characteristics and circulating steroids hormone levels in the early years of the studies, and impacts were evaluated after installation of secondary treatment (1989), major pulping process changes (1995) and after the mill ceased pulp production and effluent release (2006). The addition of secondary treatment resulted in minor improvements in wild fish health, and the conversion to elemental chlorine free (ECF) bleaching at the mill was associated with more recovery in liver and gonad size. While some impacts persist at the exposure site, reproductive parameters showed further improvement during the mill shutdown period demonstrating that biologically active chemicals are still being discharged from modernized mills. PMID:19783055

  17. Influence of irradiation of gamma-ray on the pulping and paper making, (2)

    International Nuclear Information System (INIS)

    In kraft pulping and neutral sulphite pulping of gamma-ray irradiated chips, the influence of irradiation on the defiberability of the yielded pulps were investigated. The results were summerized as follows: 1) In kraft pulping, the defiberability becomes inferior by the irradiation of 5 x 105R. 2) In neutral sulphite pulping, the defiberability seems to become somewhat better by the irradiation of 106R. And kapper number does not change within the area of the high pulp yield but it becomes smaller according to the decrease of the total pulping yield by the irradiation of 106R, in comparison with the case of no-irradiation. (author)

  18. Dental Pulp Defence and Repair Mechanisms in Dental Caries

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Farges

    2015-01-01

    Full Text Available Dental caries is a chronic infectious disease resulting from the penetration of oral bacteria into the enamel and dentin. Microorganisms subsequently trigger inflammatory responses in the dental pulp. These events can lead to pulp healing if the infection is not too severe following the removal of diseased enamel and dentin tissues and clinical restoration of the tooth. However, chronic inflammation often persists in the pulp despite treatment, inducing permanent loss of normal tissue and reducing innate repair capacities. For complete tooth healing the formation of a reactionary/reparative dentin barrier to distance and protect the pulp from infectious agents and restorative materials is required. Clinical and in vitro experimental data clearly indicate that dentin barrier formation only occurs when pulp inflammation and infection are minimised, thus enabling reestablishment of tissue homeostasis and health. Therefore, promoting the resolution of pulp inflammation may provide a valuable therapeutic opportunity to ensure the sustainability of dental treatments. This paper focusses on key cellular and molecular mechanisms involved in pulp responses to bacteria and in the pulpal transition between caries-induced inflammation and dentinogenic-based repair. We report, using selected examples, different strategies potentially used by odontoblasts and specialized immune cells to combat dentin-invading bacteria in vivo.

  19. Wood pulp characterization by a novel photoacoustic sensor

    International Nuclear Information System (INIS)

    In this paper we introduce a novel photoacoustic sensing technique that captures a photoacoustic signal excited by a laser light pulse after the light has propagated through a turbid medium. Simultaneously, the ultrasonic sound wave is captured after it has propagated through the same turbid medium. By combining the two signals, more information on the investigated medium can be obtained. Applications can be found in the pulp and paper industry where monitoring wood pulp compositions is of interest. Depending on its origin, pulp suspension contains different compositions of fibres and fibre fragments (fines). Poor control of the pulp composition leads to an unstable process that compromises the production, quality and energy efficiency in the pulp mill. The result shows the feasibility of the photoacoustic sensor in monitoring the mass fractions of fibres and fines in a pulp suspension. The first received echo, corresponding to the light interaction with the sample, showed a stronger correlation to the fines mass fraction compared to fibre mass fraction. The second echo, corresponding to the sound wave interaction with the sample, showed a much stronger correlation to fibre mass fraction than to fines mass fraction. Hence, it is proposed that by combining these two echoes, more information about the pulp suspension could be extracted than from any other sensor built on a single sensing principle. (paper)

  20. Performance of a Horizontal Triple Cylinder Type Pulping Machine

    Directory of Open Access Journals (Sweden)

    Sukrisno Widyotomo

    2011-05-01

    Full Text Available Pulping is one important step in wet coffee processing method. Pulping process usually uses a machine which constructed by wood or metal materials. A horizontal single cylinder type of fresh coffee cherries pulping machine is the most popular machine in coffee processing. One of the weaknesses of a horizontal single cylinder type of fresh coffee cherries pulping machine is higher in broken beans. Broken bean is one of mayor aspects in defect system that contribute to low quality. Indonesian Coffee and Cocoa Research Institute has designed and tested a horizontal double cylinder type of fresh coffee cherries pulping machine which resulted in 12.6—21.4% of broken beans. To reduce percentage of broken beans, Indonesian Coffee and Cocoa Research Institute has developed and tested a horizontal triple cylinder type of fresh coffee cherries pulping machine. Material tested was fresh mature Robusta coffee cherries, 60—65% (wet basis moisture content; has classified on 3 levels i.e. unsorted, small and medium, and clean from metal and foreign materials. The result showed that the machine produced 6,340 kg/h in optimal capacity for operational conditions, 1400 rpm rotor rotation speed for unsorted coffee cherries with composition 55.5% whole parchment coffee, 3.66% broken beans, and 1% beans in wet skin.Key words : coffee, pulp, pulper, cylinder, quality.

  1. Potential for biohydrogen and methane production from olive pulp

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Skiadas, Ioannis V.; Ahring, Birgitte Kiær; Lyberatos, G.

    The present study investigates the potential for thermophilic biohydrogen and methane production from olive pulp, which is the semi-solid residue coming from the two-phase processing of olives. It focussed on: a) production of methane from the raw olive pulp, b) anaerobic bio-production of hydrogen...... and hydrogen-effluent was as high as 19 mmole CH4 per g TS. This suggests that olive pulp is an ideal substrate for methane production and it shows that biohydrogen production can be very efficiently coupled with a subsequent step for methane production....

  2. STEAM EXPLOSION PULPING OF OIL PALM EMPTY FRUIT BUNCH FIBER

    OpenAIRE

    Xiwen Wang,; Jian Hu; Jingshan Zeng

    2012-01-01

    Steam explosion pulping was evaluated for oil palm empty fruit bunches fiber. The fiber morphology was observed by SEM and TEM. Results indicated that lignin was molten and the cell wall damaged after the steam explosion pulping and that the fiber was partly separated at the same time. The results of handsheet tests showed that the steam exploded pulp had a high yield (78.2%), good physical properties (especially for ring crush 8.6 N•m/g), and low effluent load (SS=910 mg/L; BOD5=3952 mg/L; C...

  3. Using renewable sources in the pulp and paper mills

    International Nuclear Information System (INIS)

    The pulp and paper industry is a major consumer of natural sources (wood) and energy (fossil fuels, electricity) and a significant contributor of pollutant discharges to the environment. In this paper there are presented pulp and paper making process and steam and power generation using renewable sources. This paper includes also an exergy analysis of the steam and power generation process for a pulp and paper mill. Based on the analysis, two sustainability indicators were calculated: the exergetic efficiency and the exergy renewability. (authors)

  4. FRACTIONATION OF PULP AND PAPER PARTICLES SELECTIVELY BY SIZE

    Directory of Open Access Journals (Sweden)

    Ossi Tapio Laitinen

    2011-02-01

    Full Text Available A study was made of the classification of pulp, paper, and peat particles by size with a device called a tube flow fractionator. An accurate and simple experimental model was formulated in order to estimate the time required for fractionation, yielding an excellent correlation between the observed and predicted fractionation times. The results showed that the fractionation time of a certain size of pulp, paper, and peat particles in the tube flow device can be accurately estimated from the length, width, and thickness of the particle. The results can be used to facilitate the selection of specific fractions of pulp and paper samples.

  5. ENVIRONMENTAL ISSUES IN THE AGRO BASED INDIAN PULP & PAPER INDUSTRY

    Institute of Scientific and Technical Information of China (English)

    S. Panwar; N.Endlay; S.Mishra; R.M.Mathur; A.G.Kulkarni

    2004-01-01

    @@ INTRODUCTION The Indian Pulp & Paper Industry is more than a century old industry . The first paper mill was established in the year 1832 and today the number has grown to more than 400 in the organised sector which are located through out the country . In addition there are another 500 pulp & paper mills in the unorganized sector. The Indian pulp & paper industry can be categorised into large, medium and small depending on the scale of operation as indicated in Table -I Most of the large mills established initially were based on woody raw materials.

  6. Food Value of Mealworm Grown on Acrocomia aculeata Pulp Flour.

    Directory of Open Access Journals (Sweden)

    Ariana Vieira Alves

    Full Text Available Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae, which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management. The bocaiuva (Acrocomia aculeata (Jacq. Lodd is an abundant palm tree found in the Brazilian Cerrado, providing fruits with high nutritional value. The aim of this work was to determine the chemical composition of T. molitor grown in different artificial diets with bocaiuva pulp flour. The nutritional composition, fatty acid composition, antioxidant activity, trypsin activity and anti-nutritional factors of larvae were analyzed. The results showed that mealworms grown on artificial diet with bocaiuva are a good source of protein (44.83% and lipid (40.45%, with significant levels of unsaturated fatty acids (65.99%, antioxidant activity (4.5 μM Trolox/g of oil extracted from larvae and absence of anti-nutritional factors. This study indicates a new source of biomass for growing mealworms and shows that it is possible to breed mealworms in artificial diet with bocaiuva flour without compromising the nutritional quality of the larvae.

  7. Food Value of Mealworm Grown on Acrocomia aculeata Pulp Flour.

    Science.gov (United States)

    Alves, Ariana Vieira; Sanjinez-Argandoña, Eliana Janet; Linzmeier, Adelita Maria; Cardoso, Claudia Andrea Lima; Macedo, Maria Lígia Rodrigues

    2016-01-01

    Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae), which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management. The bocaiuva (Acrocomia aculeata (Jacq.) Lodd) is an abundant palm tree found in the Brazilian Cerrado, providing fruits with high nutritional value. The aim of this work was to determine the chemical composition of T. molitor grown in different artificial diets with bocaiuva pulp flour. The nutritional composition, fatty acid composition, antioxidant activity, trypsin activity and anti-nutritional factors of larvae were analyzed. The results showed that mealworms grown on artificial diet with bocaiuva are a good source of protein (44.83%) and lipid (40.45%), with significant levels of unsaturated fatty acids (65.99%), antioxidant activity (4.5 μM Trolox/g of oil extracted from larvae) and absence of anti-nutritional factors. This study indicates a new source of biomass for growing mealworms and shows that it is possible to breed mealworms in artificial diet with bocaiuva flour without compromising the nutritional quality of the larvae. PMID:26974840

  8. Food Value of Mealworm Grown on Acrocomia aculeata Pulp Flour

    Science.gov (United States)

    Alves, Ariana Vieira; Sanjinez-Argandoña, Eliana Janet; Linzmeier, Adelita Maria; Cardoso, Claudia Andrea Lima; Macedo, Maria Lígia Rodrigues

    2016-01-01

    Insects have played an important role as human food throughout history, especially in Africa, Asia and Latin America. A good example of edible insects is the mealworm, Tenebrio molitor Linnaeus, 1758 (Coleoptera, Tenebrionidae), which are eaten in Africa, Asia, the Americas and Australia. This species is easily bred in captivity, requiring simple management. The bocaiuva (Acrocomia aculeata (Jacq.) Lodd) is an abundant palm tree found in the Brazilian Cerrado, providing fruits with high nutritional value. The aim of this work was to determine the chemical composition of T. molitor grown in different artificial diets with bocaiuva pulp flour. The nutritional composition, fatty acid composition, antioxidant activity, trypsin activity and anti-nutritional factors of larvae were analyzed. The results showed that mealworms grown on artificial diet with bocaiuva are a good source of protein (44.83%) and lipid (40.45%), with significant levels of unsaturated fatty acids (65.99%), antioxidant activity (4.5 μM Trolox/g of oil extracted from larvae) and absence of anti-nutritional factors. This study indicates a new source of biomass for growing mealworms and shows that it is possible to breed mealworms in artificial diet with bocaiuva flour without compromising the nutritional quality of the larvae. PMID:26974840

  9. Preparation of clinker from paper pulp industry wastes.

    Science.gov (United States)

    Buruberri, Leire H; Seabra, M P; Labrincha, J A

    2015-04-01

    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. PMID:25590818

  10. Ash from a pulp mill boiler--characterisation and vitrification.

    Science.gov (United States)

    Ribeiro, Ana S M; Monteiro, Regina C C; Davim, Erika J R; Fernandes, M Helena V

    2010-07-15

    The physical, chemical and mineralogical characterisation of the ash resulting from a pulp mill boiler was performed in order to investigate the valorisation of this waste material through the production of added-value glassy materials. The ash had a particle size distribution in the range 0.06-53 microm, and a high amount of SiO(2) (approximately 82 wt%), which was present as quartz. To favour the vitrification of the ash and to obtain a melt with an adequate viscosity to cast into a mould, different amounts of Na(2)O were added to act as fluxing agent. A batch with 80 wt% waste load melted at 1350 degrees C resulting in a homogeneous transparent green-coloured glass with good workability. The characterisation of the produced glass by differential thermal analysis and dilatometry showed that this glass presents a stable thermal behaviour. Standard leaching tests revealed that the concentration of heavy metals in the leaching solution was lower than those allowed by the Normative. As a conclusion, by vitrification of batch compositions with adequate waste load and additive content it is possible to produce an ash-based glass that may be used in similar applications as a conventional silicate glass inclusively as a building ecomaterial. PMID:20346582

  11. The role of bound chlorine in the brightness reversion of bleached hardwood kraft pulp

    OpenAIRE

    Kátia Maria Morais Eiras; Jorge Luiz Colodette; Vanessa Lopes Silva

    2009-01-01

    Our previous paper showed fragmentary evidence that pulp brightness reversion may be negatively affected by its organically bound chlorine (OX) content. A thorough investigation on eucalyptus kraft pulp led to the conclusion that OX increases reversion of certain pulps but this trend is not universal. Alkaline bleaching stages decrease reversion regardless of pulp OX content. Pulps bleached with high temperature chlorine dioxide revert less than those bleached with conventional chlorine dioxi...

  12. 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.

  13. CHLORINE DIOXIDE BLEACHING OF SODA-ANTHRAQUINONE JUTE PULP TO A VERY HIGH BRIGHTNESS

    OpenAIRE

    M. Sarwar Jahan; Yonghao Ni,; Zhibin He

    2010-01-01

    Bleaching of soda-anthraquinone jute pulp by chlorine dioxide (ClO2) was studied to reach a target brightness of above 88% for the purpose of using less bleaching chemicals. The performance of either chlorine dioxide or peroxide in the final bleaching to boost brightness was also studied. The experimental results revealed that the final brightness depended on ClO2 charge in the Do and D1 stages. The brightness reversion was lower when the final stage brightening was done by peroxide. The use ...

  14. Changes in the physicochemical and microbiological properties of frozen araça pulp during storage

    OpenAIRE

    Clarissa Damiani; Moacir Evandro Lage; Flávio Alves da Silva; Douglas Endrigo Perez Pereira; Fernanda Salamoni Becker; Eduardo Valério de Barros Vilas boas

    2013-01-01

    Araça belongs to the Myrtaceae family and is popularly known as araçá-comum, araçá-azedo, or araçá-do-campo. Frozen fruit pulp is of great importance for the food industry, which can produce it at the time of harvest, store it, and use it according to the demand of the consumer market and/or as an ingredient in the formulation of products such as yogurt, candies, and ice creams among others. The aim of this study was to evaluate the physical, chemical, and microbiological stability of frozen ...

  15. In Situ Hybridization of Pulp Fibers Using Mg-Al Layered Double Hydroxides

    OpenAIRE

    Carl-Erik Lange; Mika Lastusaari; Mehedi Reza; Seyed Kourosh Latifi; Pasi Kallio; Pedro Fardim

    2015-01-01

    Inorganic Mg2+ and Al3+ containing layered double hydroxide (LDH) particles were synthesised in situ from aqueous solution onto chemical pulp fibers of pine (Pinus sylvestris). High super saturated (hss) solution with sodium carbonate produced LDH particles with an average diameter of 100–200 nm. Nano-size (70 nm) LDH particles were found from fibers external surface and, to a lesser degree, from the S2 cell wall after synthesis via low super saturated (lss) route. The synthesis via slow urea...

  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. Comparative Study of Antioxidant Power, Polyphenols, Flavonoids and Betacyanins of the Peel and Pulp of Three Tunisian Opuntia Forms

    OpenAIRE

    Nizar Yeddes; Chérif, Jamila K.; Sylvain Guyot; Hélène Sotin; Ayadi, Malika T.

    2013-01-01

    The antioxidant activity and the chemical composition of methanol extracts from peel and pulp belonging to two species of Tunisian prickly pears Opuntia ficus indica (spiny and thornless forms) and Opuntia stricta have been studied. The antioxidant capacity was measured by DPPH radical scavenging activity. The total phenolic compound (TPC) and the total flavonoid content were determined by the Folin–Ciocalteu method and colorimetric method, respectively. The phenolic compounds were identified...

  18. Advanced Oxidation Processes for removal of COD from pulp and paper mill effluents : A Technical, Economical and Environmental Evaluation

    OpenAIRE

    Karat, Irma

    2013-01-01

    In Sweden, the dominating source for emissions of degradable organic substances to water is the pulp and paper industry. The organic substances increase oxygen consumption in the recipient which subsequently threatens aquatic species. Improved process engineering, process closures and use of external treatments have in recent years drastically lowered the Biological Oxygen Demand (BOD). However, the Chemical Oxygen Demand (COD) has not been reduced to the same extent, as some organic substanc...

  19. High-solids black liquor firing in pulp and paper industry Kraft recovery boilers. Final report, Phase 1, Volume 1: Executive summary

    Energy Technology Data Exchange (ETDEWEB)

    Southards, W.T.; Clement, J.L.; McIlroy, R.A.; Tharp, M.R.; Verrill, C.L.; Wessell, R.A.

    1995-11-01

    This project is a multiple-phase effort to develop technologies to improve high-solids black liquor firing in pulp mill recovery boilers. The objectives are to develop a preliminary design of a recovery furnace simulator; evaluate the economics of high-solids; and delineate a project concept for evaluating candidate technologies to improve chemical recovery.

  20. PREPARATION OF BAMBOO DISSOLVING PULP FOR TEXTILE PRODUCTION; PART 1. STUDY ON PREHYDROLYSIS OF GREEN BAMBOO FOR PRODUCING DISSOLVING PULP

    Directory of Open Access Journals (Sweden)

    Xiaojuan Ma

    2011-03-01

    Full Text Available Prehydrolysis was used as the first treatment of bamboo materials for producing high dissolving pulp for textile applications. In this paper, green bamboo (Dendrocalamopsis oldhami was hydrolyzed in water, and the hydrolysis process was optimized. The morphology and super-molecular structures of the raw material and prehydrolyzed material were studied by SEM and XRD, respectively. Based on the optimum conditions, a study of the kinetics and mechanism showed that pentosan dissolution during the hydrolysis process was a first order reaction. When cooking temperature was 150 oC, 160 oC, 170 oC, and 180 oC, the corresponding reaction rate constants were 0.00411h-1, 0.00495h-1, 0.00730h-1, and 0.00925h-1, respectively. The activation energy was 44.94 kJ/mol based on the Arrhenius empirical equation. SEM results revealed that after the pre-hydrolysis process, the bamboo structure became loose because of hemicellulose dissolution, which created a favorable environment for chemical penetration in the subsequent treatment. Furthermore, the degree of crystallinity was increased from 45.43% to 57.06% during the prehydrolysis. Both the treated and the untreated fibers were assumed to be cellulose I.

  1. NIRS Characterization of Paper Pulps to Predict Kappa Number

    Directory of Open Access Journals (Sweden)

    Ana Moral

    2015-01-01

    Full Text Available Rice is one of the most abundant food crops in the world and its straw stands as an important source of fibres both from an economic and an environmental point of view. Pulp characterization is of special relevance in works involving alternative raw materials, since pulp properties are closely linked to the quality of the final product. One of the analytical techniques that can be used in pulp characterization is near-infrared spectroscopy (NIRS. The use of NIRS has economic and technical advantages over conventional techniques. This paper aims to discuss the convenience of using NIRS to predict Kappa number in rice straw pulps produced under different conditions. We found that the resulting Kappa number can be acceptably estimated by NIRS, as the errors obtained with that method are similar to those found for other techniques.

  2. Pulp Stone, Haemodialysis, End-stage Renal Disease, Carotid Atherosclerosis

    OpenAIRE

    Patil, Santosh; Sinha, Nidhi

    2013-01-01

    Objectives: The aim of this study was to determine the relationship between the presence of pulp calcification and carotid artery calcification on the dental panoramic radiographs in End Stage Renal Disease (ESRD) patients who were on haemodialysis.

  3. Enhancing hemicelluloses removal from a softwood sulfite pulp.

    Science.gov (United States)

    Li, Jianguo; Zhang, Hongjie; Duan, Chao; Liu, Yishan; Ni, Yonghao

    2015-09-01

    Hemicelluloses removal is highly desirable in many biomass processes, including the pretreatment steps of the bioconversion for ethanol production, production of high-quality dissolving pulps. In this study, a sequential treatment consisting of pulp fractionation, followed by caustic treatment to remove hemicelluloses from a softwood sulfite pulp, was investigated. The long-fiber fraction obtained after pulp fractionation, had a lower hemicelluloses content and smaller specific surface area, but larger pore diameter than the short-fiber fraction. The fiber fractions were subsequently treated in a cold caustic extraction (CCE) or hot caustic extraction (HCE). Results showed that hemicelluloses removal in the long-fiber fraction was more pronounced than the short-fiber fraction in both CCE and HCE processes. Other parameters, such as hemicelluloses removal selectivity, yield were studied. The underlying explanations were given. PMID:26004557

  4. 'KLEBSIELLA' DENSITIES IN WATERS RECEIVING WOOD PULP EFFLUENTS

    Science.gov (United States)

    Surface waters receiving pulp mill effluents were examined for the presence of total coliforms, fecal coliforms, and Salmonella species. Fecal coliforms were biochemically identified as belonging to the Escherichia, Klebsiella or Enterobacter genera. Sixty percent of the isolates...

  5. Engineering aspects of enzymatic fiber solubilization from potato pulp

    DEFF Research Database (Denmark)

    Ravn, Helle Christine

    affected by the presence of calcium as calcium forms gels by interacting with protonated low-methoxylated (LM) HG hindering enzyme attacks and degradation of the HG. Initially, two types of potato pulp FiberBind, a dried commercial potato pulp product containing ~7000 ppm of calcium, and PUF, a dried......Potato pulp is a low-value by-product of the potato starch production. However, it contains valuable fibers consisting of rhamnogalacturonan I (RGI) with large galactan and arabinan side chains that can be extracted using a combination of polygalacturonase (PG) and pectin lyase (PL) which degrades...... the intestinal system. Prebiotics can counteract this imbalance by maintaining a healthy microbiota in weaning piglets. Fast enzymatic release of the potential prebiotic hairy-RGI fiber from potato pulp demanded excessive availability of HG. However, at pH 6.0 the availability of HG was strongly...

  6. Identification and Isolation of Human Dental Pulp Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Xue-Chao YANG; Ming-Wen FAN

    2005-01-01

    @@ 1 Introduction Dentinal repair in the postnatal organism occurs through the activity of specialized cells, odontoblasts,that are thought to be maintained by an as yet undefined precursor population associated with pulp tissue.

  7. Antifungal activity of fruit pulp extract from Bromelia pinguin.

    Science.gov (United States)

    Camacho-Hernández, I L; Chávez-Velázquez, J A; Uribe-Beltrán, M J; Ríos-Morgan, A; Delgado-Vargas, F

    2002-08-01

    The methanol extract of the fruit pulp of Bromelia pinguin was evaluated for its antifungal activity. The extract showed a significant activity against some Trichophyton strains, although Candida strains were generally insensitive. PMID:12165338

  8. 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...

  9. Effect of effluent from a nitrogen fertilizer factory and a pulp mill on the distribution and abundance of Aeromonas hydrophila in Albemarle Sound, North Carolina.

    OpenAIRE

    Hazen, T C; Esch, G W

    1983-01-01

    The density of Aeromonas hydrophila, standard count bacteria, fecal coliform bacteria, and 18 physical and chemical parameters were measured simultaneously at six sites for 12 months in Albemarle Sound, N.C. One site was above and two sites were below the discharge plume of a Kraft pulping process paper mill. The fourth site was above and the remaining two sites were below the discharge point of a nitrogen fertilizer factory. The impact of the pulp mill on water quality was acute, whereas tha...

  10. Optimum dose of 2-hydroxyethyl methacrylate based bonding material on pulp cells toxicity

    Directory of Open Access Journals (Sweden)

    Widya Saraswati

    2010-06-01

    Full Text Available Background: 2-hydroxyethyl methacrylate (HEMA, one type of resins commonly used as bonding base material, is commonly used due to its advantageous chemical characteristics. Several preliminary studies indicated that resin is a material capable to induce damage in dentin-pulp complex. It is necessary to perform further investigation related with its biological safety for hard and soft tissues in oral cavity. Purpose: The author performed an in vitro test to find optimum dose of HEMA resin monomer that may induce toxicity in pulp fibroblast cells. Method: The method of this study was experimental laboratory with post test control group design. Primary cell culture was made from dental pulp fibroblast cells, and was given with HEMA resin bonding material in various concentrations (5 µg/ml–2560 µg/ml, and then subjected to toxicity test (MTT assay. Result: HEMA optimum concentration was 320 µg/ml to induce cytotoxicity in pulp fibroblast cells. Conclusion: The used of HEMA - base bonding material with the concentration of 200 µg/ml may induced pulp fibroblas cell toxicity.Latar belakang: Keberhasilan suatu bahan bonding secara klinis tergantung pada kandungan fisik, kimia dan keamanan secara biologis. HEMA (2-hydroxyethyl methacrylate adalah bahan resin yang paling banyak digunakan karena memiliki sifat fisik-kimia yang baik. Beberapa penelitian pendahuluan menyebutkan bahwa resin merupakan bahan yang mampu menyebabkan gangguan pada kompleks dentin pulpa sehingga perlu dilakukan penelitian lebih lanjut menyangkut segi keamanan secara biologis bagi jaringan keras dan jaringan lunak di rongga mulut. Tujuan: Penelitian ini akan menguji secara in vitro (pada kultur sel fibroblas pulpa gigi untuk mengetahui dosis optimal monomer resin HEMA yang dapat menyebabkan toksisitas pada sel fibroblas pulpa. Metode: Metode penelitian ini adalah eksperimental laboratoris dengan rancangan penelitian post test control group design. Kultur sel primer dibuat dari

  11. Chlorhexidine gel associated with papain in pulp tissue dissolution

    OpenAIRE

    Couto De Oliveira, Gabriel; Ferraz, Caio Souza; Andrade Júnior, Carlos Vieira; PITHON, Matheus Melo

    2013-01-01

    Objectives This study aimed to evaluate the capacity of 2% chlorhexidine gel associated with 8% papain gel in comparison with 5.25% sodium hypochlorite in bovine pulp tissue dissolution. Materials and Methods Ninety bovine pulps of standardized sizes were used and fragmented into 5-mm sizes. The fragments were removed from the root middle third region. They were divided into 6 experimental groups (n = 15), 1) 8% papain; 2) 2% chlorhexidine; 3) 2% chlorhexidine associated with 8% papain; 4) 0....

  12. Histologic properties of the pulp and dentin in primary teeth

    OpenAIRE

    Özçobanoğlu, Gözdem; Durutürk, Leyla

    2013-01-01

    Many teeth, especially the primary teeth are lost prematurely despite advancements in the prevention of dental caries and increasing recognition of the importance of natural dentition. These losses may lead to malocclusion or temporary or permanent esthetic, phonetic and functional problems. Preservation of the integrity and health of oral tissues is the main target in dental pulp treatments. Although the dental pulp is similar to other loose connective tissues of the body, it differs in some...

  13. EVALUATION OF PULP STONES IN A SUBPOPULATION OF NORTHEAST TURKEY

    OpenAIRE

    KARADAŞ, Muhammet; HATİPOĞLU, Ömer; AKDAĞ, Mustafa Sadık; DEMİRBUĞA, Sezer

    2015-01-01

    Aim: To evaluate the prevalence and distribu- tion of pulp stones in posterior teeth by using digital panoramic radiographs in a Turkish subpopulation. Materials and method: Panoramic radiographs of 3,113 patients ranging in age from 15 to 35 (1,836 females and 1,277 males) were retrospectively examined to determine the prevalence and distribution of the pulp stones. All data were obtained from dental records. All posterior teeth were investigated except third molars, and the data obtained we...

  14. Influence of moderate to severe chronic periodontitis on dental pulp

    OpenAIRE

    Fatemi, K; Disfani, R; R.ZARE; A. Moeintaghavi; Ali, Saadat A.; Boostani, H. R

    2012-01-01

    Background: The relationship between periodontal disease and dental pulp changes is controversial and has been debated for many years. This human study was performed to evaluate the possible effects of moderate to advanced periodontal disease on the different aspect of dental pulp structure. Materials and Methods: Twenty hopeless permanent teeth were extracted from systemically healthy adults because of moderate to advanced chronic periodontitis, with a bone loss of >6 mm and a mobility of gr...

  15. Pectin methyl esterase activity in apple and orange pulps

    International Nuclear Information System (INIS)

    The results of pectin methyl esterase activity from apple, orange pulp and orange peel depending of ph and temperature are discussed. It's shown that the methyl esterase activity form apple and orange pulps higher in range of temperatures from +37...+60digC. The analysis of dependence of its activity from ph has shown that in both case the enzyme activity increase with increase of ph

  16. Indirect pulp capping in primary molar using glass ionomer cements

    OpenAIRE

    Murtia Metalita; Udijanto Tedjosasongko; Prawati Nuraini

    2014-01-01

    Background: Indirect pulp capping in primary teeth, however, is more rarely conducted than permanent teeth, since it thought to have low impact and most suggestion is for taking caries lesion aggressively on primary teeth. Purpose: The study was aimed to evaluate the subjective complaint, clinical symptom, and radiographic appearance of indirect pulp capping treatment using glass ionomers cements in primary molar. Methods: Sixteen children in range of age 6 to 8 years old, who visited Clinic ...

  17. Amelogenins in human developing and mature dental pulp

    OpenAIRE

    Ye, L.; Le, TQ; L. Zhu; Butcher, K.; Schneider, RA; Li, W.; Den Besten, PK

    2006-01-01

    Amelogenins are a group of heterogenous proteins first identified in developing tooth enamel and reported to be present in odontoblasts. The objective of this study was to elucidate the expression and function of amelogenins in the human dentin-pulp complex. Developing human tooth buds were immunostained for amelogenin, and mRNA was detected by in situ hybridization. The effects of recombinant amelogenins on pulp and papilla cell proliferation were measured by Brd U immunoassay, and different...

  18. Pulp-dentin Regeneration: Current State and Future Prospects.

    Science.gov (United States)

    Cao, Y; Song, M; Kim, E; Shon, W; Chugal, N; Bogen, G; Lin, L; Kim, R H; Park, N-H; Kang, M K

    2015-11-01

    The goal of regenerative endodontics is to reinstate normal pulp function in necrotic and infected teeth that would result in reestablishment of protective functions, including innate pulp immunity, pulp repair through mineralization, and pulp sensibility. In the unique microenvironment of the dental pulp, the triad of tissue engineering would require infection control, biomaterials, and stem cells. Although revascularization is successful in resolving apical periodontitis, multiple studies suggest that it alone does not support pulp-dentin regeneration. More recently, cell-based approaches in endodontic regeneration based on pulpal mesenchymal stem cells (MSCs) have demonstrated promising results in terms of pulp-dentin regeneration in vivo through autologous transplantation. Although pulpal regeneration requires the cell-based approach, several challenges in clinical translation must be overcome-including aging-associated phenotypic changes in pulpal MSCs, availability of tissue sources, and safety and regulation involved with expansion of MSCs in laboratories. Allotransplantation of MSCs may alleviate some of these obstacles, although the long-term stability of MSCs and efficacy in pulp-dentin regeneration demand further investigation. For an alternative source of MSCs, our laboratory developed induced MSCs (iMSCs) from primary human keratinocytes through epithelial-mesenchymal transition by modulating the epithelial plasticity genes. Initially, we showed that overexpression of ΔNp63α, a major isoform of the p63 gene, led to epithelial-mesenchymal transition and acquisition of stem characteristics. More recently, iMSCs were generated by transient knockdown of all p63 isoforms through siRNA, further simplifying the protocol and resolving the potential safety issues of viral vectors. These cells may be useful for patients who lack tissue sources for endogenous MSCs. Further research will elucidate the level of potency of these iMSCs and assess their

  19. Characterization of Progenitor Cells in Pulps of Murine Incisors

    OpenAIRE

    Balic, A.; Mina, M.

    2010-01-01

    The continuous growth of rodent incisors requires the presence of stem cells capable of generating ameloblasts and odontoblasts. While epithelial stem cells giving rise to ameloblasts have been well-characterized, cells giving rise to the odontoblasts in incisors have not been fully characterized. The goal of this study was to gain insight into the potential population in dental pulps of unerupted and erupted incisors that give rise to odontoblasts. We show that pulps from unerupted incisors ...

  20. ON THE RECOVERY OF HEMICELLULOSE BEFORE KRAFT PULPING

    OpenAIRE

    Carlos Vila; Javier Romero; José Luis Francisco,; Valentín Santos,; Juan Carlos Parajó

    2012-01-01

    To assess the feasibility of implementing hemicellulose recovery stages in kraft mills, Eucalyptus globulus wood samples were subjected to aqueous treatments with hot, compressed water (autohydrolysis processing) to achieve partial dissolution of xylan. Autohydrolyzed solids were subjected to kraft pulping under selected conditions to yield a pulp of low kappa number, and to an optimized TCF bleaching sequence made up of three stages (alkaline oxygen delignification, chelating, and pressurize...

  1. Use of Coffee Pulp and Minerals for Natural Soil Ameliorant

    OpenAIRE

    Pujiyanto Pujiyanto

    2007-01-01

    In coffee plantation, solid waste of coffee pulp is usually collected as heap nearby processing facilities for several months prior being used as compost. The practice is leading to the formation of odor and liquid which contaminate the environment. Experiments to evaluate the effect of natural soil ameliorant derived from coffee pulp and minerals were conducted at The Indonesian Coffee and Cocoa Research Institute in Jember, East Java. The experiments were intended to optimize the use of cof...

  2. Pulp vitality preservation after traumatic dental injuries to permanent teeth

    OpenAIRE

    Blagojević Duška; Petrović Bojan; Marković Dejan; Vujkov Sanja; Demko-Rihter Ivana

    2013-01-01

    Introduction. The pulp vitality preservation after a trauma to permanent teeth is of great importance since dental injuries are common. The aim of our study was to investigate the pulp vitality preservation after tooth injuries. Material and Methods. A retrospective analysis of records of patients with a trauma was performed. The sample consisted of all patients who had been referred to the Department of Dentistry of Vojvodina for a trauma to permanent teeth during the period 2005-2010....

  3. Timing of pulp extirpation for replanted avulsed teeth.

    LENUS (Irish Health Repository)

    Stewart, Chris

    2009-01-01

    A search was performed (April 2004) across four databases, namely Ovid Medline, Cochrane Library, PubMed and Web of Science, relevant to the proposed PICO ( Patient or problem, Intervention, Comparison, Outcome) question: (P) for a replanted avulsed permanent tooth, (I) is early pulp extirpation within 10-14 days of replantation, (C) compared with delayed pulp extirpation, (O) associated an increased likelihood of successful periodontal healing after tooth replantation. Only articles published in the English language were considered.

  4. Avaliação química de geléias de manga formuladas com diferentes níveis de cascas em substituição à polpa Chemical evaluation of mango (Mangifera indica L jams formulated with different levels of peels in substitution to pulp

    Directory of Open Access Journals (Sweden)

    Clarissa Damiani

    2009-02-01

    Full Text Available Objetivou-se, neste estudo, avaliar a qualidade de geléias formuladas com níveis de 0 %, 25 %, 50 %, 75 % e 100 % de cascas em substituição à polpa de manga (Mangifera indica L. cv. Haden. Os critérios de qualidade utilizados foram os teores de umidade, cinzas, proteínas, lipídios, carboidratos totais, açúcares totais, açúcares redutores, sacarose, vitamina C, fibra insolúvel, pectina, acidez titulável e sólidos solúveis nas polpas e cascas das mangas e nos diferentes tratamentos. Observou-se que nos tratamentos com substituição da polpa por cascas encontraram-se teores significativamente maiores de proteínas, fibras insolúveis e sacarose e menores valores calóricos, acidez titulável, carboidratos totais e açúcares totais em relação ao controle. Os tratamentos foram semelhantes em relação ao teor de vitamina C e sólidos solúveis. Com a elevação dos níveis de cascas em substituição à polpa observou-se aumento do teor de cinzas, fibras insolúveis e sacarose e redução dos açúcares redutores. Concluiu-se que a substituição parcial ou total de polpa por cascas de manga na formulação melhora o valor nutricional e funcional das geléias apesar da diminuição do valor calórico, com benefícios econômicos e ambientais.The aim of this study was to evaluate the quality of jams formulated with peel levels of 0%, 25%, 50%, 75% and 100% in substitution to mango pulp (Mangifera indica L. cv. Haden. The quality criteria were moisture, ashes, proteins, fat, total carbohydrate, total sugars, reducing sugars, sucrose, vitamin C, insoluble fiber, pectin, titrable fruit acidity, soluble solids contents and pH in the mango pulp, mango peels and different treatments. It was observed that in the treatments with substitution of pulp by peels, the contents of proteins, insoluble fiber and sucrose were significantly higher than the control. The caloric values, titrable fruit acidity, total carbohydrate and total sugars were

  5. Preparation and characterization of cellulose nanofibers from de-pectinated sugar beet pulp.

    Science.gov (United States)

    Li, Meng; Wang, Li-jun; Li, Dong; Cheng, Yan-ling; Adhikari, Benu

    2014-02-15

    Cellulose nanofibers (diameter=10-70 nm) were produced using chemical treatments (alkali treatment and bleaching) and high pressure homogenization from de-pectinated sugar beet pulp (DSBP). Chemical analysis and Fourier transform infrared spectroscopy (FTIR) indicated that the chemical treatments greatly removed the hemicellulose and lignin from the DSBP and significantly increased the cellulose content. The crystallinity of the cellulose nanofibers increased from 35.67% to 69.62% after alkali treatment and bleaching. The thermal degradation temperature of DSBP cellulose nanofibers was 271.7 °C which was found to be 47.3 °C higher than that of the untreated DSBP. The DSBP cellulose nanofibers can be preferably used as reinforcement in the biocomposite material at high temperature. PMID:24507265

  6. Visibility of dental pulp spaces in dental ultrasound.

    Science.gov (United States)

    Szopinski, K T; Regulski, P

    2014-01-01

    The purpose of this study was to assess the feasibility of dental ultrasound with conventional sonographic equipment. The teeth of three adult volunteers who had cone beam CT examinations performed previously with clinical indications and one extracted tooth were examined using linear and compact (hockey stick) sonographic probes. The sonographic images were compared with cone beam CT images reconstructed accordingly. Dental pulp spaces were demonstrated in all teeth not covered with prosthetic crowns. The dentin and pulp were best visualized at the level of the neck of the teeth. The dentin was hypoechoic, and the superficial layer comprising the cementum and the pulp spaces were hyperechoic. Dental ultrasound is feasible with general purpose sonographic machines. The buccal surfaces of all teeth are accessible with a compact (hockey stick) probe. Visualization and differentiation of dental pulp spaces, dentin and the superficial layer comprising cementum is possible in the portions of teeth not covered by the alveolar bone or prosthetic crowns. The dental pulp spaces are best seen at the level of the tooth neck. Pulp and endodontic fillings can be distinguished on ultrasound. PMID:24170803

  7. Implant-Root Proximity and Pulp Vitality of the Tooth

    Directory of Open Access Journals (Sweden)

    Tasharoie

    2015-12-01

    Full Text Available Background When dental implants are applied in partially edentulous patients, there is the risk of placing the implants in close proximity or in direct contact with the adjacent roots. In this situation assurance of pulp vitality of the adjacent tooth is neessary. Objectives The current study aimed to assess pulp response of the tooth after root proximity with dental implant. Patients and Methods After investigating 2800 records of patients, 31 implants in 29 patients were included in this study. A parallel peri-apical radiography was taken and pulp vitality tests (cold, heat and electrical pulp tests were conducted for each patient. Results Among the 31 assessed implants and the adjacent intact teeth, 13 implants had direct contact and 18 implants had proximity of less than 1 mm with the adjacent root. All of the teeth had positive (normal pulp response to all tests. The most prevalent areas for proximity of implant-tooth were upper first premolar implants and upper canine teeth. The most approximation area was apical third of root of the teeth. Conclusions Based on the clinical and radiographic examinations, implant-tooth approximation (less than 1 mm or direct contact is not related to pulp vitality of the tooth. Further studies with larger sample sizes are necessary to confirm the results of the study.

  8. Binding and desulfurization characteristics of pulp black liquor in biocoalbriquettes.

    Science.gov (United States)

    Kim, Heejoon; Lu, Guoqing; Li, Tianji; Sadakata, Masayoshi

    2002-04-01

    To control pollutant emissions from coal combustion in some developing countries, biocoalbriquette, an artificially produced solid fuel, was developed. Both the breaking strength and production costs of the biocoalbriquette have become essentially the most important factors in popularizing it in these countries. To increase the breaking strength and decrease the production costs, it is proposed in this study to use pulp black liquor, a byproduct from the pulp production industry, as a binder. The influences of pulp black liquor on the briquetting and combustion characteristics were investigated. Furthermore, the desulfurization characteristics of pulp black liquor were also evaluated through combustion experiments. The study results show that the briquetting pressure has a limited effect on the breaking strength. An increase in the briquetting pressure yields greater breaking strength of up to the 50 MPa. Above 50 MPa, the breaking strength changes very little with the briquetting pressure. The use of pulp black liquor has had a greater effect on increasing the breaking strength than on changing the briquetting pressure and also on improving the combustion characteristics of the biocoalbriquette. On the other hand, pulp black liquor has some desulfurization capabilities. When used as a binder, it not only increases the breaking strength and decreases the necessary briquetting pressure, but it also improves some characteristics of the combustion and reduces the pollutants emission. PMID:11999073

  9. Biological evaluation of nanosilver incorporated cellulose pulp for hygiene products.

    Science.gov (United States)

    Kavitha Sankar, P C; Ramakrishnan, Reshmi; Rosemary, M J

    2016-04-01

    Cellulose pulp has a visible market share in personal hygiene products such as sanitary napkins and baby diapers. However it offers good surface for growth of microorganisms. Huge amount of research is going on in developing hygiene products that do not initiate microbial growth. The objective of the present work is to produce antibacterial cellulose pulp by depositing silver nanopowder on the cellulose fiber. The silver nanoparticles used were of less than 100 nm in size and were characterised using transmission electron microscopy and X-ray powder diffraction studies. Antibacterial activity of the functionalized cellulose pulp was proved by JIS L 1902 method. The in-vitro cytotoxicity, in-vivo vaginal irritation and intracutaneous reactivity studies were done with silver nanopowder incorporated cellulose pulp for introducing a new value added product to the market. Cytotoxicity evaluation suggested that the silver nanoparticle incorporated cellulose pulp is non-cytotoxic. No irritation and skin sensitization were identified in animals tested with specific extracts prepared from the test material in the in-vivo experiments. The results indicated that the silver nanopowder incorporated cellulose pulp meets the requirements of the standard practices recommended for evaluating the biological reactivity and has good biocompatibility, hence can be classified as a safe hygiene product. PMID:26838891

  10. METHOD FOR AUTOMATIC ANALYSIS OF WHEAT STRAW PULP CELL TYPES

    Directory of Open Access Journals (Sweden)

    Mikko Karjalainen,

    2012-01-01

    Full Text Available Agricultural residues are receiving increasing interest when studying renewable raw materials for industrial use. Residues, generally referred to as nonwood materials, are usually complex materials. Wheat straw is one of the most abundant agricultural residues around the world and is therefore available for extensive industrial use. However, more information of its cell types is needed to utilize wheat straw efficiently in pulp and papermaking. The pulp cell types and particle dimensions of wheat straw were studied, using an optical microscope and an automatic optical fibre analyzer. The role of various cell types in wheat straw pulp and papermaking is discussed. Wheat straw pulp components were categorized according to particle morphology and categorization with an automatic optical analyzer was used to determine wheat straw pulp cell types. The results from automatic optical analysis were compared to those with microscopic analysis and a good correlation was found. Automatic optical analysis was found to be a promising tool for the in-depth analysis of wheat straw pulp cell types.

  11. Biotechnological potential of coffee pulp and coffee husk for bioprocesses.

    Science.gov (United States)

    Pandey; Soccol; Nigam; Brand; Mohan; Roussos

    2000-10-01

    Advances in industrial biotechnology offer potential opportunities for economic utilization of agro-industrial residues such as coffee pulp and coffee husk. Coffee pulp or husk is a fibrous mucilagenous material (sub-product) obtained during the processing of coffee cherries by wet or dry process, respectively. Coffee pulp/husk contains some amount of caffeine and tannins, which makes it toxic in nature, resulting the disposal problem. However, it is rich in organic nature, which makes it an ideal substrate for microbial processes for the production of value-added products. Several solutions and alternative uses of the coffee pulp and husk have been attempted. These include as fertilizers, livestock feed, compost, etc. However, these applications utilize only a fraction of available quantity and are not technically very efficient. Attempts have been made to detoxify it for improved application as feed, and to produce several products such as enzymes, organic acids, flavour and aroma compounds, and mushrooms, etc. from coffee pulp/husk. Solid state fermentation has been mostly employed for bioconversion processes. Factorial design experiments offer useful information for the process optimization. This paper reviews the developments on processes and products developed for the value-addition of coffee pulp/husk through the biotechnological means. PMID:10959086

  12. Seeking optimality in fruit pulping schedules: A case study*

    Directory of Open Access Journals (Sweden)

    J.H. Van Vuuren

    2014-01-01

    Full Text Available The process of scheduling fruit pulping for the production of fruit juices is of great importance in the beverage industry. Decisions have to be made regarding available processing time, the disposal of fruit that will not be pulped before stock loss due to spoilage, the fulfilment of customer demand and an optimal financial position. Sheduling depends on the capacity of the work force, pulping machine limitations and delivery deadlines. However, the situation is often encountered where the plant manager has to decide which fruit batches (usually from stock piles of overwhelming proportions during the harvesting season are to be pulped in order to minimize losses due to fruit deterioration. Such decisions are usually done manually, based on intuition and experience. A mathematical model is presented here which constructs a pulping strategy while minimising cascading financial losses associated with fruit grade drops within the stock pile. It is shown in particular that a minimisation of fruit losses is not a good criterion for optimality, and that substantial financial gains may be accomplished when minimising financial losses in stead of fruit losses, which is currently standard practice at most fruit pulping plants.

  13. KAPOK I: CHARACTERISTCS OF KAPOK FIBER AS A POTENTIAL PULP SOURCE FOR PAPERMAKING

    Directory of Open Access Journals (Sweden)

    Somporn Chaiarrekij,

    2011-11-01

    Full Text Available The potential use of kapok fiber for pulping and papermaking has been investigated. The kapok fibers were cooked using the optimal dosage of sodium hydroxide determined from the experiments. Then, the pulp was refined with two passes using a disc refiner and mixed with commercial hardwood pulp and/or softwood pulp at different blend ratios to make papers. It was found that addition of the kapok pulp to the mixed pulps improved the tensile and burst strengths of the sheets but decreased the tear resistance and elongation. Water repellency of the sheets prepared from the kapok pulp mixed with the commercial pulps was also improved. These results indicate that kapok fiber can be a quality pulp source for papermaking, especially for packaging paper requiring strength and water repellency.

  14. Stem cell-based pulp tissue engineering: variables enrolled in translation from the bench to the bedside, a systematic review of literature.

    Science.gov (United States)

    Conde, M C M; Chisini, L A; Demarco, F F; Nör, J E; Casagrande, L; Tarquinio, S B C

    2016-06-01

    Stem cell-based therapy (SC-BT) is emerging as an alternative for endodontic therapies. The interaction between stem cells and scaffolds plays a crucial role in the generation of a 'friendly cell' microenvironment. The aim of this systematic review was to explore techniques applied to regenerate the pulp-dentine complex tissue using SC-BT. An electronic search into the SciVerse Scopus (SS), ISI Web Science (IWS) and Entrez PubMed (EP) using specific keywords was performed. Specific inclusion and exclusion criteria were predetermined. The search yielded papers, out of which full-text papers were included in the final analyses. Data extraction pooled the results in four main topics: (a) influence of the chemical properties of the scaffolds over cell behaviour; (b) influence of the physical characteristics of scaffolds over cell behaviour; (c) strategies applied to improve the stem cell/scaffold interface; and (d) influence of cue microenvironment on stem cell differentiation towards odontoblast-like cells and pulp-like tissue formation. The relationship between the scaffolds, the environment and the growth factors released from dentine are critical for de novo pulp tissue regeneration. The preconditioning of dentine walls with ethylenediaminetetraacetic acid (EDTA) was imperative for successful pulp-dentine complex regeneration. An analyses of the grouped results revealed that pulp regeneration was an attainable goal. PMID:26101143

  15. Effect of ripe fruit pulp on the sensory and nutritive quality of ready-to-eat breakfast cereal produced from maize and soybean flours and cassava starch blends.

    Science.gov (United States)

    Enwere, N J; Ntuen, I G

    2005-02-01

    The effects of various concentrations of different ripe fruit pulps on the sensory and nutritive quality of breakfast cereal were studied. The breakfast cereal was formulated using 1 kg composite flour (composed of 600 g maize flour and 400 g soy flour) in addition to 100 g cassava starch, 225 g sugar and 12 g salt. Pineapple, pawpaw and banana ripe fruit pulps were added separately to the breakfast formulation at concentrations of 0, 100, 200, 300 and 400 g/kg composite flour. Using sensory evaluation, the data obtained showed that samples containing 100 g pineapple, 100 g banana pulp and 100 g pawpaw fruit pulp per kilogram of composite flour (equivalent to 7% of the total weight of the breakfast cereal formulation) were the most acceptable of all concentrations. These samples were comparable in sensory evaluation scores with the commercial breakfast cereal sample Golden morn. Chemical analysis also showed that there was increase in ss-carotene (vitamin A precursor) and vitamin C and a slight increase in the mineral content of the breakfast cereal as a result of the addition of fruit pulp. PMID:16019313

  16. THE RELATIONSHIP OF THE CHRONIC RENAL FAILURE WITH CAROTID ARTERY CALCIFICATIONS, DENTAL PULP CALCIFICATIONS AND DENTAL PULP STONES

    OpenAIRE

    DAĞISTAN, Saadettin; MİLOĞLU, Özkan

    2015-01-01

    ABSTRACT Objective: The aim of this study was to investigate the existence of carotid artery calcifications in dental panoramic radiographs and dental pulp calcifications together with dental pulp stones in periapical radiographs in patients with chronic renal failure undergoing haemodialysis and healthy individuals, and to identify the relationship between the two groups.Patients and methods: A total of 115 cases (57 patients on haemodialysis for chronic renal failure and 58 healthy individu...

  17. High consistency refining of mechanical pulps during varying refining conditions : High consistency refiner conditions effect on pulp quality

    OpenAIRE

    Muhic, Dino

    2008-01-01

      The correlation between pulp properties and operating conditions in high consistency (HC) refiners at Holmen Paper AB were studied. Two types of HC refiners were investigated: the Andritz RTS refiner at the Hallstavik Mill and the Sprout-Bauer Twin 60 refiner at the Braviken Mill. The objective of the study was to clarify the relationship between the pulp properties and refining conditions such as electrical energy input, housing- and feed- pressure and plate wear in high consistency refini...

  18. Nutrient contents of the fresh pulps and dried pulp cakes of vitellaria paradoxa of Gulu District, Uganda

    DEFF Research Database (Denmark)

    Oryema, Christine; Oryem-Origa, Hannington; Roos, Nanna

    2016-01-01

    Vitellaria paradoxa Gaertn locally known as ‘Yaa’ in Acholi is a valuable edible indigenous wild fruit in Gulu District, northern Uganda. It is a multipurpose fruit tree and highly favoured by the inhabitants of this district. Its fruit pulps are eaten when fresh and/or made into cakes and dried....... This study determined the nutrient compositions of the fresh pulps and dried pulp cakes of V. paradoxa. Laboratory analyses were undertaken to determine the micro and macro nutrients in the samples on fresh (FM) and dry matter (DM) basis following standard procedures and protocols. The potassium......, sodium and calcium contents of the fresh pulps on FM basis were, respectively 38, 7.3 and 234 mg/100 g. The contents of zinc (1.00 mg/100 g), Iron (6.8 mg/100 g) and magnesium (92.01 mg/100 g) on FM basis were the highest in the dried pulp cakes compared to the contents in the fresh pulp cakes. The fresh...

  19. The role of bound chlorine in the brightness reversion of bleached hardwood kraft pulp

    Directory of Open Access Journals (Sweden)

    Kátia Maria Morais Eiras

    2009-01-01

    Full Text Available Our previous paper showed fragmentary evidence that pulp brightness reversion may be negatively affected by its organically bound chlorine (OX content. A thorough investigation on eucalyptus kraft pulp led to the conclusion that OX increases reversion of certain pulps but this trend is not universal. Alkaline bleaching stages decrease reversion regardless of pulp OX content. Pulps bleached with high temperature chlorine dioxide revert less than those bleached with conventional chlorine dioxide in sequences ending with a chlorine dioxide stage but similarly in sequences ending with a final peroxide stage. The use of secondary condensate for pulp washing decreases reversion.

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

    Directory of Open Access Journals (Sweden)

    M. A. Quaiyyum

    2008-08-01

    Full Text Available 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. The soda-EDA process produced better pulp yield, kappa number, viscosity, and α-cellulose content as compared to the kraft process. Increasing EDA charge in the soda liquor increased pulping selectivity and α-cellulose content. Degraded cellulose (R18-R10 in soda-EDA pulp was lower than kraft pulp. But the bleachability of soda-EDA pulp was inferior as compared to kraft pulp in DED bleaching.

  1. QUALITY of PULP AND JELLIES of TAMARIND FROM THE BRAZILIAN CERRADO

    Directory of Open Access Journals (Sweden)

    Leandro de Morais CARDOSO

    2012-08-01

    Full Text Available This study aimed assess the physical characteristics (mass, length and width of tamarind fruit (Tamarindus indica L. and the physical-chemical characteristics (moisture, ash, proteins, lipids, dietary fiber, titratable acidity, soluble solids and pH of the pulp and jellies of tamarind. The jelly formulations were prepared containing different concentrations of tamarind juice (40 and 50% and pectin (1.0 and 1.2%. The formulations were subjected to preference and acceptance tests. The tamarind presented a high pulp yield (50.3% as well as high contents of carbohydrates (68.60g 100g-1, fiber (5.55g 100g-1 and titratable acidity (18.56g tartaric acid 100g-1. There were no significant differences in the chemical composition and acceptance of the jellies. The acceptance of the formulations was higher than 5 (I liked for all parameters evaluated (appearance, color, odor, texture, flavor and overall evaluation. In conclusion, the tamarind was rich in carbohydrates, fiber and organic acids. The jellies were well accepted by the panelists. The tamarind jelly production was feasible and represents an effective option for the better utilization and conservation of the fruit.

  2. ISOTHERMAL PYROLYSIS OF KRAFT PULP MILL SLUDGE

    Directory of Open Access Journals (Sweden)

    Syamsudin Syamsudin

    2014-12-01

    Full Text Available Kraft pulp mill sludge cake composed of rejected wood fibers and activated sludge microorganisms. With a heating value about 14 MJ/kg (dried basis, this type of biomass had a potential as an alternative energy source. Unfortunately, it had an ash content of 27.6% and a moisture content of 80%. For reducing moisture content with minimum energy consumption, a combination of mechanical dewatering and thermal drying was studied previously. Meanwhile, experiments on isothermal pyrolysis had been carried out for further improvement on ultimate and proximate analysis of solid fuel. Final mass of char obtained from pyrolysis at 500oC was not significantly different from that of 700oC, so pyrolysis was considered to be optimum at 500oC. A char obtained from pyrolysis at temperature of 500oC had a pore surface area of 77.049 m2/g (highest among other temperatures. Kinetic of isothermal pyrolysis was well represented with a first order modified volumetric model with a frequency factor of 0.782 1/s and an activation of 34.050 kJ/mol.

  3. Enhanced oil recovery chemicals from renewable wood resources

    Energy Technology Data Exchange (ETDEWEB)

    Grune, W.N.; Compere, A.L.; Griffith, W.L.; Crenshaw, J.M.

    1979-04-01

    Most of the wood pulp in the U.S. is produced by cooking, or digesting, wood chips in a chemical solution. These pulping processes have effluent streams which contain dissolved lignins, lignin breakdown products, and carbohydrates. There is a substantial economic incentive to use these materials as feedstocks for the production of high-valued micellar flood chemicals. The pulp and paper industries have practiced chemical recovery for almost a century. The largest chemical recycle processes are the internal recycle of inorganic salts for reuse in pulping. This is coupled with the use of waste organic compounds in the liquor as a fuel for directly-fired evaporation processes. Diversion of effluent and low valued streams for chemical recovery using fermentation, purification, or synthesis methods appears technically feasible in several cases. The use of new recovery processes could yield a variety of different wood-effluent based products. Some of the sugar acids in pulping liquors might be used as sequestering agents in reservoirs where there are large amounts of multivalent cations in flood brines. Fermentation production of high viscosity polymers, sequestering agents, and coagent alcohols appears worth further investigation. Tall oil acids and their derivatives can be used as surfactants in some reservoirs. Some waste constituents may adsorb preferentially on formations and thereby reduce loss of surfactants and other higher-valued chemicals.

  4. Methane potentials of the Swedish pulp and paper industry – A screening of wastewater effluents

    International Nuclear Information System (INIS)

    Highlights: ► The fiber fraction of the KP mills holds a large methane potential. ► CH4-yields of the alkaline ECF effluents were higher when hardwood was processed. ► Acidic ECF-effluents were shown to be the most toxic to the AD-flora. ► Effluents from TMP and NSSC mills gave CH4-yields >40% of the theoretical potential. ► Most samples from the CTMP mills yielded 40–50% of the theoretical CH4-potential. - Abstract: With the final aim of reducing the energy consumption and increase the methane production at Swedish pulp and paper mills, the methane potential of 62 wastewater effluents from 10 processes at seven pulp and/or paper mills (A–G) was determined in anaerobic batch digestion assays. This mapping is a first step towards an energy efficient and more sustainable utilization of the effluents by anaerobic digestion, and will be followed up by tests in lab-scale and pilot-scale reactors. Five of the mills produce kraft pulp (KP), one thermo-mechanical pulp (TMP), two chemical thermo-mechanical pulp (CTMP) and two neutral sulfite semi-chemical (NSSC) pulp. Both elementary and total chlorine free (ECF and TCF, respectively) bleaching processes were included. The effluents included material from wood rooms, cooking and oxygen delignification, bleaching (often both acid- and alkali effluents), drying and paper/board machinery as well as total effluents before and after sedimentation. The results from the screening showed a large variation in methane yields (percent of theoretical methane potential assuming 940 NmL CH4 per g TOC) among the effluents. For the KP-mills, methane yields above 50% were obtained for the cooking effluents from mills D and F, paper machine wastewater from mill D, condensate streams from mills B, E and F and the composite pre-sedimentation effluent from mill D. The acidic ECF-effluents were shown to be the most toxic to the AD-flora and also seemed to have a negative effect on the yields of composite effluents downstream while

  5. The annual frequency of root fillings, tooth extractions and pulp-related procedures in Danish adults during 1977-2003

    DEFF Research Database (Denmark)

    Bjørndal, L.; Reit, C.

    2004-01-01

    endodontic epidemiology, frequency of root fillings, pulp capping, stepwise excavation, tooth extractions......endodontic epidemiology, frequency of root fillings, pulp capping, stepwise excavation, tooth extractions...

  6. MOLYBDENUM CATALYZED ACID PEROXIDE BLEACHING OF EUCALYPTUS KRAFT PULP

    Directory of Open Access Journals (Sweden)

    Marcos S. Rabelo

    2008-08-01

    Full Text Available Molybdenum catalyzed peroxide bleaching (PMo Stage consists of pulp treatment with hydrogen peroxide under acidic conditions in the presence of a molybdenum catalyst. Molybdenum is applied in catalytic doses (50-200 mg/kg pulp and may originate from various sources, including (NH46Mo7O24.4H2O, Na2MoO4.2H2O, siliconmolybdate, etc. This work is aimed at optimizing the PMo stage and evaluating its industrial application in the OAZDP sequence. Optimum PMo stage conditions for bleaching eucalyptus pulp were 90 ºC, pH 3.5, 2 h, 0.1 kg/adt Mo and 5 kg/adt H2O2. The PMo stage was more efficient to remove pulp hexenuronic acids than lignin. Its efficiency decreased with increasing pH in the range of 1.5-5.5, while it increased with increasing temperature and peroxide and molybdenum doses. The application of the PMo stage as replacement for the A-stage of the AZDP sequence significantly decreased chlorine dioxide demand. The PMo stage caused a decrease of 20-30% in the generation of organically bound chlorine. The quality parameters of the pulp produced during the PMo stage mill trial were comparable to those obtained with the reference A-stage.

  7. Pulp tissue in sex determination: A fluorescent microscopic study

    Directory of Open Access Journals (Sweden)

    Amit Nayar

    2014-01-01

    Full Text Available Aims: To determine and compare the reliability of pulp tissue in determination of sex and to analyze whether caries have any effect on fluorescent body test. Materials and Methods: This study was carried on 50 maxillary and mandibular teeth (25 male teeth and 25 female teeth, which were indicated for extraction. The teeth are categorized into 5 groups, 10 each (5 from males and 5 from females on the basis of caries progression. The pulp cells are stained with quinacrine hydrochloride and observed with fluorescent microscope for fluorescent body. Gender is determined by identification of Y chromosome fluorescence in dental pulp. Results: Fluorescent bodies were found to be more in sound teeth in males as the caries increase the mean percentage of fluorescent bodies observed decreases in males. We also observed the fluorescent spots in females, and the value of the spot increases in female as the caries progresses, thereby giving false positive results in females. Conclusion: Sex determination by fluorescent staining of the Y chromosome is a reliable technique in teeth with healthy pulps or caries with enamel or up to half way of dentin. Teeth with caries involving pulp cannot be used for sex determination.

  8. Pulp vitality preservation after traumatic dental injuries to permanent teeth

    Directory of Open Access Journals (Sweden)

    Blagojević Duška

    2013-01-01

    Full Text Available Introduction. The pulp vitality preservation after a trauma to permanent teeth is of great importance since dental injuries are common. The aim of our study was to investigate the pulp vitality preservation after tooth injuries. Material and Methods. A retrospective analysis of records of patients with a trauma was performed. The sample consisted of all patients who had been referred to the Department of Dentistry of Vojvodina for a trauma to permanent teeth during the period 2005-2010. We recorded the type of injury, treatment, state of vitality during the first visit and subsequent check-ups. Results. The study included 162 children and adolescents aged 6-18 years having a trauma to 314 permanent teeth. The most frequent type of injuries in permanent teeth was fractures (54.5%, whereas luxation was a less common trauma (45.5%. Though different kinds of traumas have different optimal time for treatment, a period of 24 hours was taken as optimal; hence, 189 teeth were treated in optimal time and 55 complications occurred in them; while 105 complications occurred in 114 teeth which were treated 24 hours after the trauma. A year after the trauma the pulp vitality was preserved in 88 teeth (32%, pulp necrosis and other complications developed in 160 teeth (68%. Conclusion. The therapy of pulp vitality preservation in injured teeth was found successful in 32% and unsuccessful in 68% of cases at check-ups over one year.

  9. 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...

  10. Indirect pulp capping and primary teeth: is the primary tooth pulpotomy out of date?

    Science.gov (United States)

    Coll, James A

    2008-07-01

    Formocresol pulpotomy (FP) in the United States is most frequently used to treat asymptomatic caries near the pulp in primary teeth. Indirect pulp therapy (IPT) is also indicated and has a significantly higher long-term success. Pulpotomy is thought to be indicated for primary teeth with carious pulp exposures, but research shows the majority of such teeth are nonvital or questionable for treatment with vital pulp therapy. IPT has a significantly higher success in treating all primary first molars, but especially those with reversible pulpitis compared with FP. The purpose of this article was to review the dental literature and new research in vital pulp therapy to determine the following: (1) Is a pulpotomy indicated for a true carious pulp exposure? (2) Is there a diagnostic method to reliably identify teeth that are candidates for vital pulp therapy? (3) Is primary tooth pulpotomy out of date, and should indirect pulp therapy replace pulpotomy? PMID:18565370

  11. >Effect of progesterone hormon on cell viability and stem cell activation in dental pulp cells

    OpenAIRE

    Segah Altuntaş; Muhammed Ali Kara; Deniz Selin Aksoy; Zehra Dilşad Çoban; Şefik Güran

    2016-01-01

    Objective: The dental pulp is the part in the center of a tooth made up of living connective tissue and cells called odontoblasts. The vitality of the dentin structure, both during health and after injury, depends on pulp cell activity and the signaling processes that regulate the cell’s behavior. Dental pulp tissue has condensed stem cell activity. Dental pulp stem cells are multipotent stem cells that have the potential to differentiate into a variety of cell types. Several publications hav...

  12. Process for the preparation of a high freeness beaten low lignin pulp with high strength

    OpenAIRE

    Dekker, J.C.

    2005-01-01

    The present invention relates to a process for the preparation of a high freeness beaten low lignin pulp with a high strength. More particularly, the present invention relates to a process for the preparation of a high freeness beaten low lignin pulp that is produced from a pulp with a low lignin content, wherein said pulp with a low lignin content is subjected to a beating process under relatively high compression forces and relatively low shear forces

  13. Waste management from pulp and paper production in the European Union

    OpenAIRE

    Monte Lara, María Concepción; Fuente González, Elena de la; Blanco Suárez, Ángeles; Negro Álvarez, Carlos Manuel

    2009-01-01

    Eleven million tonnes of waste are produced yearly by the European pulp and paper industry, of which 70% originates from the production of deinked recycled paper. Wastes are very diverse in composition and consist of rejects, different types of sludges and ashes in mills having on-site incineration treatment. The production of pulp and paper from virgin pulp generates less waste but the waste has similar properties to waste from the production of deinked pulp, although with less inorganics. D...

  14. Characterization of stem and progenitor cells in the dental pulp of erupted and unerupted murine molars

    OpenAIRE

    Balic, Anamaria; Aguila, H. Leonardo; Caimano, Melissa J.; Francone, Victor P.; Mina, Mina

    2010-01-01

    In the past few years there have been significant advances in the identification of putative stem cells also referred to as “mesenchymal stem cells” (MSC) in dental tissues including the dental pulp. It is thought that MSC in dental pulp share certain similarities with MSC isolated from other tissues. However, cells in dental pulp are still poorly characterized. This study focused on the characterization of progenitor and stem cells in dental pulps of erupted and unerupted mice molars. Our st...

  15. Root maturation and dentin–pulp response to enamel matrix derivative in pulpotomized permanent teeth

    OpenAIRE

    Darwish, Sherif S; Abd El Meguid, Shadia H; Wahba, Nadia A; Mohamed, Ahmed A-R; Chrzanowski, Wojciech; Abou Neel, Ensanya A

    2014-01-01

    The success of pulpotomy of young permanent teeth depends on the proper selection of dressing materials. This study aimed to evaluate the histological and histomorphometric response of dentin–pulp complex to the enamel matrix derivative (Emdogain® gel) compared to that of calcium hydroxide when used as a pulp dressing in immature young permanent dogs’ teeth. Dentin-like tissues bridging the full width of the coronal pulp at the interface between the injured and healthy pulp tissues were seen ...

  16. Hemicellulases in the bleaching and characterisation of kraft pulps. Doctoral thesis

    Energy Technology Data Exchange (ETDEWEB)

    Suurnaekki, A.

    1996-03-01

    Xylanase-aided bleaching of kraft pulps is the major industrial application of hemicellulases in pulp processing. In addition to process aids, hemicellulases have recently also been shown to be promising tools in fibre analytics. In this work, the role of xylanase and mannanase pretreatments in the bleaching of softwood pulps produced by different sulphate cooking methods was studied. In addition, the action of hemicellulases in kraft fibres was characterized and exploited in the analysis of the suface composition of kraft pulps.

  17. The energy saving potential of a new mechanical pulping process; Puristushieronnan mahdollisuudet mekaanisen massanvalmistuksen energiakulutuksen pienentaemisessae

    Energy Technology Data Exchange (ETDEWEB)

    Pietarila, V. (UPM-Kymmene OYj, Lappeenranta (Finland))

    2008-07-01

    The target of this project is to develop a new mechanical pulping process to produce papermaking pulp from chips. Energy consumption of this process should be remarkably lower than in mill processes today. In earlier small scale studies it has been pointed out that it could be possible to produce acceptable pulp in a process that differs from todayAEs pulp production methods. Anyhow extensive research efforts are required to test and develop this new process. (orig.)

  18. Performance of a Horizontal Double Cylinder Type of Fresh Coffee Cherries Pulping Machine

    OpenAIRE

    Sukrisno Widyotomo; Sri Mulato; H. Ahmad; S. Soekarno

    2009-01-01

    Pulping is one important step in wet coffee processing method. Usually, pulping process uses a machine which constructed using wood or metal materials. A horizontal single cylinder type coffee pulping machine is the most popular machine in coffee processor and market. One of the weakness of a horizontal single cylinder type coffee pulping machine is high of broken beans. Broken beans is one of major aspect in defect system that result in low quality. Indonesian Coffee and Cocoa Research Insti...

  19. Research on the properties of dope-dyed bamboo pulp staple fibers

    Science.gov (United States)

    Zhang, Y. J.

    2016-07-01

    In order to understand the properties of the dope-dyed bamboo pulp staple fibers, the moisture regains, tensile properties, friction properties and electrical conductivity of them and the white bamboo pulp fiber were tested, compared and analyzed. The results show that the moisture regains of the dope-dyed bamboo pulp fibers are smaller than the white bamboo pulp fiber's, whereas their friction coefficients, breaking strengths and elongations and mass ratio resistances are a bit larger.

  20. Micro-tensile bond strength of adhesives to pulp chamber dentin after irrigation with Ethylenediaminetetraacetic acid

    OpenAIRE

    Ç Barutcigil; Arslan, H; Özcan, E; O T Harorli

    2012-01-01

    Aim: The aim of this study was to evaluate the influence of different concentrations of Ethylenediaminetetraacetic acid (EDTA) solution on adhesion, that is, the bond strength of the different adhesive systems, to the pulp chamber dentin. Materials and Methods: Recently extracted, sound, human, third molars were cut horizontally to expose the pulp horn. The roof of the pulp chamber and pulp tissue was removed. The teeth were then divided into five main groups. The teeth in each group were tre...

  1. Aspects of the methodology validation for light filth in fruit pulp

    OpenAIRE

    Dimov, M. N.; Atui, M. B.; de Silva, A. M.; Marciano, M. A. M.; Franco, V. P .A.; Chasin, L. B.; Silva, L. A.; Fioravanti, M. I. A.; Oliveira, M. M. L.

    2010-01-01

    Methodology validation is an important tool to support the activities of metrology in the quantification analysis. Extraneous materials may be present in the pulps due to the conditions or the practices of production, storage and distribution. Since there is no specific methodology for fruit pulp light filth quantification a research has been carried out to test two methods for isolation of light filth in mango, strawberry, tomato and guava pulps. For guava, mango and tomato pulps the AOAC Of...

  2. Adhesi Penguat Serbuk Pulp Tandan Kosong Sawit Teresterifikasi Dengan Matriks Komposit Polietilena

    OpenAIRE

    Daulay, Lely Risnawaty

    2010-01-01

    Empty Fruit Bunches (EFB) Pulp from waste of empty fruit bunches contain the lignoselulose which high enough can be exploited by as reinforcerment composite of Poliethyilene ( PE). But adhesion between Pulp (EFB) in low matrix poliethylene because different in character. for the investigated by the influence of size measure 1,50 µm and 6,75 µm from esterification flour pulp empty fruit bunches to matrix PE which is compared by pulp empty fruit bunches do not esterification. In this res...

  3. Physico-chemical evaluation of Dovyalis spp

    Science.gov (United States)

    The purpose of this research was to establish physico-chemical characterization of dovyalis hybrid fruits (MIA 25359). Samples of 30 fruits were characterized by evaluation of fruit and seed weight, length and width, percentage and number of seeds per fruit, peel and pulp percentage, total soluble s...

  4. Soda pulp and fuel gases synthesis from Hesperaloe funifera.

    Science.gov (United States)

    Sánchez, Rafael; Rodríguez, Alejandro; Requejo, Ana; Ferrer, Ana; Navarro, Enrique

    2010-09-01

    The main objective of this work is to evaluate the suitability of Hesperaloe funifera which is an alternative raw material, for pulping with soda-anthraquinone to produce pulp and paper. It was studied the influence of operational variables (temperature (155-185 degrees C), cooking time (20-60 min) and soda concentration (5-15%), with a constant addition of 1% of anthraquinone and a liquid/solid ratio of 8, in soda-anthraquinone cooking of H. funifera on pulps and paper sheets properties obtained. Finally, the cooking liquors were acidified to separate solid fractions that were subjected to pyrolysis and gasification in order to obtain synthesis and fuel gases. H. funifera contains little lignin and abundant alpha-cellulose; this, together with the morphological characteristics of its fibers, makes it a potentially highly useful papermaking raw material. PMID:20430614

  5. Magnet options for sensors for the pulp and paper industry

    International Nuclear Information System (INIS)

    The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that uses a magnetic field. The applications for magnetic sensors that have studied include (1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, (2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and (3) sensors for measuring paper thickness and water content as the paper is being processed. These tasks can be done using nuclear magnetic resonance (NMR). The magnetic field used for doing the NMR can come from either permanent magnets or superconducting magnets. The choice of the magnet is dependent on a number of factors, which include the size of the sample and field strength needed to do the sensing task at hand. This paper describes some superconducting magnet options that can be used in the pulp and paper industry.

  6. [Utilization of organic resources in paper pulp waste liquid].

    Science.gov (United States)

    Lin, Qiaojia; Liu, Jinghong; Yang, Guidi; Huang, Biao

    2005-04-01

    In this paper, one hundred percent of condensed sulfate paper pulp waste liquid was used as the raw material of adhesive, and the activation of its lignin as well as the improving effects of phenol formaldehyde resin and polyfunctional aqueous polymer isocyanate (PAPI) were studied. The results showed that adding formaldehyde to the waste liquid could increase the reactivity of contained lignin, and adding 30% phenol formaldehyde resin or 20% PAPI could make the waste liquid in place of pure phenol formaldehyde resin for producing class I plywood. Furthermore, the cost could be reduced by 55.5% and 49.0%, respectively, in comparing with pure phenol formaldehyde resin. This approach fully used the organic resources in paper pulp waste liquid, reduced environment pollution at the same time, and had unexceptionable economic, social and ecological benefits. The feasibility of preparing adhesives from paper pulp waste liquid was also analyzed by infrared spectrum. PMID:16011170

  7. Physical and chemical characterization of the pulp of different varieties of avocado targeting oil extraction potential Caracterização física e química da polpa de diferentes variedades de abacate visando o potencial para extração de óleo

    Directory of Open Access Journals (Sweden)

    Edinéia Dotti Mooz

    2012-06-01

    Full Text Available The aim of this study was to evaluate the physicochemical properties of avocado pulp of four different varieties (Avocado, Guatemala, Dickinson, and Butter pear and to identify which has the greatest potential for oil extraction. Fresh avocado pulp was characterized by moisture, protein, fat, ash, carbohydrates and energy contents were determined. The carotenoids and chlorophyll contents were determined by the organic solvent extraction method. The results showed significant differences in the composition of the fruit when varieties are compared. However, the striking feature in all varieties is high lipid content; Avocado and Dickinson are the most suitable varieties for oil extraction, taking into account moisture content and the levels of lipids in the pulp. Moreover, it could be said that the variety Dickinson is the most affected by the parameters evaluated in terms of overall quality. Chlorophyll and carotenoids, fat-soluble pigments, showed a negative correlation with respect to lipids since it could be related to its function in the fruit. The varieties Avocado and Dickinson are an alternative to oil extraction having great commercial potential to be exploited thus avoiding waste and increasing farmers’ income.O objetivo deste estudo foi avaliar as características físico-químicas da polpa de abacate de quatro diferentes variedades (Avocado, Guatemala, Dicson e Manteiga, visando identificar qual possui maior potencial para extração de óleo. A polpa de abacate fresca foi caracterizada através da determinação dos teores de umidade, proteína, lipídios, cinzas, carboidratos e valor energético. Os teores de carotenoides e clorofila foram determinados através do método de extração com solvente orgânico. Os resultados mostram diferenças significativas na composição dos frutos, quando se confrontam as variedades. No entanto, a característica marcante em todas as variedades é o alto teor de lipídios, sendo as variedades

  8. Generation of biogas from coffee-pulp and cow-dung co-digestion: Infrared studies of postcombustion emissions

    International Nuclear Information System (INIS)

    Graphical abstract: Batch digester with coffee pulp/cow dung produced high amounts of methane for 8 months. The FTIR gas spectroscopy analysis revealed the presence of over 70 chemical compounds in biogas generated after 4 months of coffee pulp and cow dung mixture co-digestion, several being hazardous to environment and human and animal health (e.g. isocyanic acid, bromomethane). Biogas produced was burned in a laboratory combustor. The FTIR gas spectroscopy analysis showed that combustion emissions contained: CH4, C3H8, CO, SO2, HI, and probably Br2 which are strongly harmful to human and animal health. - Highlights: • Batch digester with coffee pulp/cow dung produced high amounts of methane for 8 months. • Biogas from coffee pulp/cow dung codigestion contained 60% methane and 20% propane. • Biogas FTIR analysis revealed the presence of isocyanic acid and bromomethane. • Biogas FTIR analysis showed also the presence of HI. • Biogas combustion emissions contained CH4, HI, SO2 and probably Br2. - Abstract: Biogas could be produced by the co-digestion of coffee-pulp and cow-dung mixture under solar radiation. Gas chromatography and FTIR spectroscopy were used to analyze the chemical compositions of the generated biogas and its postcombustion emissions. From the first month of co-digestion at mesophylic conditions, methane content in the biogas attains 50% of the yield. This content increased up to 60% and remained almost constant for at least 8 months of further digestion. The FTIR gas spectroscopy analysis revealed the presence of over 70 chemical compounds in the biogas generated after 4 months of co-digestion along with several compounds hazardous to environment and animal health like isocyanic acid, and bromomethane. Combustion emission of the biogas contained several components like CH4, C3H8, CO, SO2, HI, and probably Br2 which are strongly harmful to human and animal health. Results presented in this work indicate that if the biogas is to be

  9. The enzymatic hydrolysis of pretreated pulp fibers predominantly involves “peeling/erosion” modes of action

    Science.gov (United States)

    2014-01-01

    Background There is still considerable debate regarding the actual mechanism by which a “cellulase mixture” deconstructs cellulosic materials, with accessibility to the substrate at the microscopic level being one of the major restrictions that limits fast, complete cellulose hydrolysis. In the work reported here we tried to determine the predominant mode of action, at the fiber level, of how a cellulase mixture deconstructs pretreated softwood and hardwood pulp fibers. Quantitative changes in the pulp fibers derived from different pretreated biomass substrates were monitored throughout the course of enzymatic hydrolysis to see if the dominant mechanisms involved either the fragmentation/cutting of longer fibers to shorter fibers or their “peeling/delamination/erosion,” or if both cutting and peeling mechanisms occurred simultaneously. Results Regardless of the source of biomass, the type of pretreatment and the chemical composition of the substrate, under typical hydrolysis conditions (50°C, pH 4.8, mixing) longer pulp fibers (fiber length >200 μm) were rapidly broken down until a relatively constant fiber length of 130 to 160 μm was reached. In contrast, shorter fibers with an initial average fiber length of 130 to 160 μm showed no significant change in length despite their substantial hydrolysis. The fragmentation/cutting mode of deconstruction was only observed on longer fibers at early stages of hydrolysis. Although the fiber fragmentation mode of deconstruction was not greatly influenced by enzyme loading, it was significantly inhibited by glucose and was mainly observed during initial mixing of the enzyme and substrate. In contrast, significant changes in the fiber width occurred throughout the course of hydrolysis for all of the substrates, suggesting that fiber width may limit the rate and extent of cellulose hydrolysis. Conclusion It appears that, at the fiber level, pretreated pulp fibers are hydrolyzed through a two-step mode of action

  10. Effects of Ethanol Pulping on the Length of Bamboo Cellulose

    Institute of Scientific and Technical Information of China (English)

    Tao Yang; Liao Junhe; Luo Xuegang

    2006-01-01

    On the conditions of different ethanol concentration, acids and catalyzers, the effects of ethanol pulping on the cellulose length of bamboo were studied. The results indicates that ethanol pulping has remarkable effects on the length of cellulose, which is clearly reduced with adding ethanol and acid. The margin of length of cellulose become smaller with the increase of the catalyzer. When the ethanol concentration was 70%, the concentration of acid was 0.3% and some NaOH was used as catalyzer, the length of cellulose was the longest.

  11. Mini Review: Dental Pulp as a Source for Paleomicrobiology

    Directory of Open Access Journals (Sweden)

    Tung Nguyen-Hieu

    2011-06-01

    Full Text Available Paleomicrobiology is a recent science. Paleomicrobiology describes the history of infectious diseases through research of ancient microbes. The dentistry with the tooth in particular has contributed to the progress of this science. The dental pulp is very well protected in the centre of the tooth. Molecular techniques such as “suicide PCR” and Multiple Spacer Typing have identified and characterized micro-organisms in the ancient samples. The detection of bacterial DNA from ancient dental pulp provided the scientific evidences for diagnosis of the infectious diseases of the past. The cooperation of paleomicrobiology and paleodontology also contributed the new knowledge to human pathology.

  12. On the application of grits to thermomechanical pulp refining

    Energy Technology Data Exchange (ETDEWEB)

    Somboon, P.

    2009-07-01

    The objective of this thesis was to develop a mechanical pulping process capable of producing good-quality pulp, while consuming less electrical energy. The study focused on applying of grits to TMP refining to enhance the breaking of the fiber cell wall promoting faster development of pulp fibers to the desired quality for papermaking. The study comprises tests at laboratory scale and development of an application for industrial, including trials at pilot scale A preliminary trial with the grit application in TMP refining was conducted at laboratory scale. The results showed that the grits should be introduced between the first and second stages in TMP refining. The grit treatment on the TMP fibers caused disruption of the wall structure, opening of the outer layers and peeling-off of the cell wall. The efficient disruption with minimal shortening and weakening of fibers was found to be operated at a low-intensity and high-frequency of treatment. According to an experiment with first-stage TMP pulp, the disrupted pulp developed faster during subsequent refining, while the energy consumption was reduced by up to 30% without a significant loss of pulp quality. With the aim of developing an industrial application, the refiner segments were modified by applying grits on the refiner segment surfaces. The grits were made from self-fluxing tungsten-carbide powder and a Ni-base alloy powder, which were laser-clad onto the surface of breaker bars, the inner part of a segment. Trials with grit segments were carried out on a pilot refiner. The grit segments were applied in first-stage TMP refining, followed by treatment with base segments operated under normal mill conditions. The grit segments were found to have no negative effects on the refining system. A refiner equipped with grit segments, operated at a speed of 2400 rpm, produced pulp with a higher level of disruption of fiber cell walls than a refiner equipped with the reference segments. According to the results, the

  13. MOLYBDENUM CATALYZED ACID PEROXIDE BLEACHING OF EUCALYPTUS KRAFT PULP

    OpenAIRE

    Marcos S. Rabelo; Jorge L. Colodette; Vera M. Sacon; Marcelo R. Silva; Marco A. B. Azevedo

    2008-01-01

    Molybdenum catalyzed peroxide bleaching (PMo Stage) consists of pulp treatment with hydrogen peroxide under acidic conditions in the presence of a molybdenum catalyst. Molybdenum is applied in catalytic doses (50-200 mg/kg pulp) and may originate from various sources, including (NH4)6Mo7O24.4H2O, Na2MoO4.2H2O, siliconmolybdate, etc. This work is aimed at optimizing the PMo stage and evaluating its industrial application in the OAZDP sequence. Optimum PMo stage conditions for bleaching eucalyp...

  14. Identification and Isolation of Human Dental Pulp Stem Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionDentinal repair in the postnatal organism occurs through the activity of specialized cells, odontoblasts, that are thought to be maintained by an as yet undefined precursor population associated with pulp tissue. Adult pulp stem cells was found in 2000. Now, it become a critical research in the world and a new stem-cells resourse for potential clinical applications. But, specific marker of DPSCs is not clear. STRO-1 was the marker that used universally. But, the expression rate was very low in...

  15. Preparation and physical properties of grafted bagasse pulp metal complexes

    International Nuclear Information System (INIS)

    The effect of grafting on the electrical properties of bleached bagasse pulp has been investigated over a frequency range 1-200 Khz. The conductivity increases upon grafting with acrylic acid or acrylonitrile. Grafted bleached bagasse pulp with acrylic acid showed an increase in the dielectric constant ε and dielectric loss ε. The bagasse/acrylic acid copolymer metal complexes have shown further increase in the conductivity. The conductivity decreases as the degree of grafting increased from 25% to 215%, indicating slower rate of complexation at higher grafting percentage

  16. Environmental regulation of the Norwegian pulp and paper industry

    International Nuclear Information System (INIS)

    The report discusses how the Norwegian pulp and paper industry has adapted to the emission requirements given by the Norwegian Pollution Control Authority (SFT) during the last 30 years. The authors have identified process alterations and internal measures in the factories that are due to stricter emission requirements, and they have identified external cleaning measures. The report also documents the interaction between the companies and SFT and it maps out real and permitted emissions to water and air from the Norwegian pulp and paper industry

  17. Experimental studies on pulp and paper mill sludge ash behavior in fluidized bed combustors

    Energy Technology Data Exchange (ETDEWEB)

    Latva-Somppi, J. [VTT Chemical Technology, Espoo (Finland). Process Technology

    1998-11-01

    Ash formation during the fluidized bed combustion (FBC) of pulp and paper mill sludges has been experimentally studied on an industrial and bench scale. The methods included aerosol measurements, chemical and crystalline composition analyses, thermogravimetry and electron microscopy. Fly ash mass and number size distributions and elemental enrichment in submicron particles and bottom ash were measured. Fly ash, bottom ash and ash deposits were characterized and their formation mechanisms are discussed. During combustion the fine paper-making additives in sludge, clay minerals and calcite, sintered fanning porous agglomerates. The fly ash mass mean size was 7.5 - 15 lam and the supermicron particles included 93.6 - 97.3 % of the fly ash. Condensation of the volatilized inorganic species formed spherical submicron particles in the fly ash. Their mass concentration was almost negligible when co-firing paper mill sludges and wood. This suggests that the fraction of the volatilized inorganic species in the paper mill sludges was low. Results from pulp mill sludge and bark co-firing were different. A clear mass mode below 0.3 pm, presenting 2.2 - 5.0 weight-% of the fly ash was detected. The condensed species included K, Na, S and Cl. Their mass fraction was higher in the pulp mill sludge than in the paper mill sludge. Evidently this resulted in increased volatilization and formation of condensed particles. The following trace elements were enriched in the submicron ash during pulp mill sludge and wood co-firing: As, Cd, Rb and Pb. The main part of the volatile species was, however, captured in the bulk ash. Presumably, this was due to the high surface area concentration in the bulk ash. Sludge moisture was observed to reduce the inorganic species volatilization. Probably steam vaporization from the wet sludge through the burning layer decreased combustion temperatures on char surface and less char was produced. Hence, the volatilization of ash forming species was

  18. Catalytic oxidation of pulping effluent by activated carbon-supported heterogeneous catalysts.

    Science.gov (United States)

    Yadav, Bholu Ram; Garg, Anurag

    2016-01-01

    The present study deals with the non-catalytic and catalytic wet oxidation (CWO) for the removal of persistent organic compounds from the pulping effluent. Two activated carbon-supported heterogeneous catalysts (Cu/Ce/AC and Cu/Mn/AC) were used for CWO after characterization by the following techniques: temperature-programmed reduction, Fourier transform infrared spectroscopy and thermo-gravimetric analysis. The oxidation reaction was performed in a batch high-pressure reactor (capacity = 0.7  L) at moderate oxidation conditions (temperature = 190°C and oxygen pressure = 0.9 MPa). With Cu/Ce/AC catalyst, the maximum chemical oxygen demand (COD), total organic carbon (TOC) and lignin removals of 79%, 77% and 88% were achieved compared to only 50% removal during the non-catalytic process. The 5-day biochemical oxygen demand (BOD5) to COD ratio (a measure for biodegradability) of the pulping effluent was improved to 0.52 from an initial value of 0.16. The mass balance calculations for solid recovered after CWO reaction showed 8% and 10% deduction in catalyst mass primarily attributed to the loss of carbon and metal leaching. After the CWO process, carbon deposition was also observed on the recovered catalyst which was responsible for around 3-4% TOC reduction. PMID:26508075

  19. Determination of sugars, organic acids, aroma components, and carotenoids in grapefruit pulps.

    Science.gov (United States)

    Zheng, Huiwen; Zhang, Qiuyun; Quan, Junping; Zheng, Qiao; Xi, Wanpeng

    2016-08-15

    The composition and content of sugars, organic acids, volatiles and carotenoids, in the pulps of six grapefruit cultivars, were examined by HPLC and GC-MS. The results showed that sucrose was the dominant sugar in grapefruit, making up 40.08-59.68% of the total sugars, and the ratio of fructose to glucose was almost 1:1. Citric acid was the major organic acid and represented 39.10-63.55% of the total organic acids, followed by quininic acid. The ratios of individual sugars and organic acids play an important role in grapefruit taste determination. Monoterpenes and sesquiterpenes were the predominant volatiles in grapefruit, in particular d-limonene and caryophyllene. Caryophyllene, α-humulene, humulen-(v1), β-linalool and tert-butyl 2-methylpropanoate are the characteristic aroma compounds of grapefruit. Although β-carotene is the primary carotenoid in grapefruit, the pulp color is mainly determined by the ratios of zeaxanthin, β-cryptoxanthin and lycopene. Our results provide the first complete chemical characterization of the taste, aroma and color of grapefruit. PMID:27006221

  20. Effect of Extraction Conditions on Quality of Pectin Extracted from Irradiated Sugar Beet Pulp

    International Nuclear Information System (INIS)

    Pectin is used in a number of foods as a gelling agent, thickener, texturizer, emulsifier and stabilizer. Sugar-beet pulp, the residue from sugar industry, is a rich source of pectin. Beet pulp pectin was extracted by using acids under various conditions from ph and temperatures but this method has problems such as pollution and hydrolysis. In this study we avoid these problems by using enzymic pectin (bio extraction). In this method we used different microorganisms tested for their ability to produce proto pectin-solubilizing enzymes. Bacillus subtilis and Pichia polymorphia. Chemical components of the extracted pectin were determined and compared, and study the quality of pectin under different conditions of ph, period of incubation and age of inoculum, also the quantity of pectin extracted by incubation with Bacillus, and Pichia were study. The results show that the best conditions were at ph 6, at the optimum period incubation 8-16 h and 24 h age of inoculum. The best yield of pectin obtained by Pichia polymorphia without Bacillus subtilis

  1. Oil quality of passion fruit seeds subjected to a pulp-waste purification process

    Directory of Open Access Journals (Sweden)

    Suelen Alvarenga Regis

    2015-06-01

    Full Text Available Passion fruit seeds must be clean and dry before the extraction processing to obtain high-quality oil for edible and cosmetic purposes. This research studies the viability of a cleaning process of seeds by evaluating the oil quality. The research examined 2 maturation stages of the fruit and one purification process of the seeds, compared to the control. The oil quality was evaluated by fatty acid composition, acidity, peroxide value and oxidative stability. The pulp waste suffered a thermal treatment in an alkaline water solution at 60°C for 10min and was further purified in an experimental decanter. In the control treatment, the pulp waste was processed using only water at ambient conditions. The passion fruit seeds were totally cleaned by the thermal/chemical treatment, allowing a faster drying (less than 50% of the drying time of the seeds and a bit higher yield of oil extraction (proportionally around 7.7%, without changes in quality of the oil

  2. Characterization and mesenteric lymph node cells-mediated immunomodulatory activity of litchi pulp polysaccharide fractions.

    Science.gov (United States)

    Huang, Fei; Zhang, Ruifen; Liu, Yang; Xiao, Juan; Su, Dongxiao; Yi, Yang; Wang, Guangjin; Wei, Zhencheng; Zhang, Mingwei

    2016-11-01

    Three water-soluble hetero-polysaccharides, designated LP1-3, were isolated from litchi pulp. Their structures, solution properties and immunomodulatory activities were evaluated. LP1 contained (1→4,6)-β-d-Glc and (1→4)-α-l-Gal, while LP2 contained (1→3)-α-l-Ara and (l→2)-β-d-Gal, and LP3 contained α-l-Ara and (l→4)-β-Rha. Their molecular weights ranged from 105,880 to 986,470g/mol. LP1 had a spherical conformation with hyper-branched structure and LP2 was semi-flexible chain, while the polysaccharide chains of LP3 were cross linked to form network-like conformation in solution. In addition, all fractions strongly stimulated mesenteric lymph node cell proliferation, IFN-γ and IL-6 secretion in the dose range of 25-100μg/mL compared with untreated control group (pcell proliferation and cytokine secretion, which may be attributed to its unique chemical structure and chain conformation. This is the first report on the solution properties and intestinal immunity activities of polysaccharides from litchi pulp. PMID:27516297

  3. Separation of lignocelluloses from spent liquor of NSSC pulping process via adsorption.

    Science.gov (United States)

    Dashtban, Mehdi; Gilbert, Allan; Fatehi, Pedram

    2014-04-01

    Hemicelluloses and lignin present in the spent liquor (SL) of neutral sulfite semichemical (NSSC) pulping process can potentially be converted into value-added products such as furfural, hydroxymethylfurfural, levulinic acid, phenols and adhesives. However, the direct conversion of hemicelluloses and lignin of SL into value-added products is uneconomical due to the dilute nature of the SL. To have a feasible downstream process for utilizing lignocelluloses of SL, the lignocelluloses should initially be separated from the SL. In this study, an adsorption process (via applying activated carbon) was considered for isolating the dissolved lignin and hemicelluloses from the SL of an NSSC pulping process. Under the optimal conditions of pH, SL/AC weight ratio, time and temperature of 5.7, 30, 360 min and 30 °C, the maximum lignin and hemicellulose adsorptions were 0.33 and 0.25 g/g on AC. The chemical oxygen demand (COD) and turbidity of the SL were decreased by 11% and 39%, respectively, as a result of lignocellulose adsorption on AC. Also, the incineration behavior of the SL-treated AC was studied with a thermo-gravimetric analysis (TGA). PMID:24565877

  4. Combined effects of independent variables on yield and protein content of pectin extracted from sugar beet pulp by citric acid.

    Science.gov (United States)

    Li, De-Qiang; Du, Guang-Ming; Jing, Wei-Wen; Li, Jun-Fang; Yan, Jia-Yu; Liu, Zhi-Yong

    2015-09-20

    The extraction of pectin from sugar beet pulp by citric acid was carried out under different conditions using Box-Behnken design for four independent variables (pH, temperature, time and liquid to solid ratio). The yield of sugar beet pulp pectin ranged from 6.3% to 23.0%, and the content of protein from 1.5% to 4.5%. All independent variables significantly affected the yield, and all variables except liquid to solid ratio significantly affected the protein content. The yield increased as decreasing pH of extracting solution, extending time and advancing temperature, and an opposite relationship of effects between variables and content of protein was obtained. The chemical composition of collected samples was determined. Moreover, from the results of emulsifying properties study, the extracted pectin from sugar beet pulp could prepare steady oil-in-water emulsions. Therefore, it was inferred that the extraction conditions could influence yield and protein content, resulting in different emulsifying property. PMID:26050895

  5. A case study of waste management at the Northern Finnish pulp and paper mill complex of Stora Enso Veitsiluoto Mills.

    Science.gov (United States)

    Nurmesniemi, Hannu; Pöykiö, Risto; Keiski, Riitta Liisa

    2007-01-01

    This work presents the current waste management system at the pulp and paper mill complex of Stora Enso Oyj Veitsiluoto Mills at Kemi, Northern Finland. This paper covers examples of case studies carried out at the mill and describes how the wastes and by-products are utilized as a neutralizing agent for acidic wastewaters (i.e., green liquor dregs from the causticizing process), as a hardener in filling mine cavities (i.e., ash from the fluidized bed boiler), as a landscaping agent (i.e., ash as well as the fibre clay from chemical wastewater treatment plant), as a hydraulic barrier material for landfills (i.e., fibre clay), and as a soil enrichment agent (i.e., calcium carbonate from the precipitated calcium carbonate plant). In addition, the wood waste from the wood-handling plant, sawmill, packaging pallet plant and from the groundwood mill, as well as the biosludge from the biological wastewater treatment plant, are all incinerated in the fluidized bed boiler for energy production. Due to effective utilization of the solid wastes generated at the mills, the annual amount of waste to be disposed of in the landfill has decreased between 1994 and 2004 from 42,990 to 6083 tonn (expressed as wet weight). The paper also gives an overview of the relevant European Union legislation on the forest industry and on waste management, as well as of the pulping process and of the generation of major solid wastes in the pulp and paper mills. PMID:16987647

  6. Determinations of the Colloidal Structure of Pulp Fibres by Adsorption in Liquid Medium. The Role of Pulping Process

    OpenAIRE

    László Koltai; Miklósné Baksay; Sándor Rohrsetzer

    2008-01-01

    We used the principles of theoretical colloid chemistry and our earlier results.We developed further the measuring of the specific surface by adsorption method. The aimof the study was the change of the usability of the method in showing out the structuraldifferences of the pulping process. We found that the different pulping processes results indifferences of the specific surface of the fibres measured with iron/III/hydroxide, TiO2 andMethylene blue adsorption, and we also found that the spe...

  7. 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)

    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

  8. Antigenotoxic activity and antioxidant properties of organic and aqueous extracts of pequi fruit (Caryocar brasiliense Camb. pulp

    Directory of Open Access Journals (Sweden)

    Ana L. Miranda-Vilela

    2008-12-01

    Full Text Available The daily consumption of natural antioxidants protects against oxidative damage caused by reactive oxygen species (ROS, including DNA damage, and can reduce the risk of cancer, atherosclerosis and other degenerative diseases. The pulp of pequi (Caryocar brasiliense Camb. fruit, a tree native to the Brazilian savannah, contains several compounds with antioxidant properties, including carotenoids, vitamin C, phenolic compounds such as flavonoids, saponins and tannins, and essential oils. In this work, we examined the ability of organic and aqueous extracts of pequi fruit pulp to protect against the genotoxicity induced by two antineoplastic drugs, cyclophosphamide (CP and bleomycin (BLM. Micronucleus tests with mouse bone marrow cells and single-cell gel electrophoresis (comet assay with peripheral blood leukocytes were used to examine the effects of CP and BLM, respectively. The antioxidant activity of the extracts was assessed by measuring lipid peroxidation with the TBARS method in mouse plasma. The fruit pulp extracts had no clastogenic or genotoxic effects in the cells studied, but both extracts protected against oxidative DNA damage caused by BLM or CP, indicating an ability to inhibit chemical mutagenesis in vivo. However, the protective effect against oxidative DNA damage depended on the dose of extract used. At the doses tested, the aqueous extract enhanced lipid peroxidation in mice of both sexes, especially in males. In contrast, the organic extract enhanced lipid peroxidation only in male mice, with no significant effect in females. These results suggest that, with adequate adjustment of the dose, an organic extract of pequi fruit pulp could be a useful dietary supplement with natural antioxidant activity, at least in females.

  9. Recovery of ovary size, follicle cell apoptosis, and HSP70 expression in fish exposed to bleached pulp mill effluent

    Energy Technology Data Exchange (ETDEWEB)

    Janz, D. M.; Weber, L. P. [Oklahoma State Univ., Stillwater, OK (United States); McMaster, M. E.; Munkittrrick, K. R. [Environment Canada, Burlington, ON (Canada); Van Der Kraak, G. [Guelph Univ., Dept. of Zoology, ON (Canada)

    2001-03-01

    Apoptosis of granulosa cells that provide hormonal support for the oocyte is the normal mechanism by which atresia ( reduced ovarian size, decreased fecundity, delayed sexual maturation, alterations in plasma sex steroid levels, etc) occurs in mammals, birds and possibly fish. The objective of this study is to determine ovarian cell apoptosis, gonadosomatic index (GSI) and heat shock protein (HSP70) expression during the growth stage of ovarian development in white sucker fish in order to compare samples of fish collected upstream and downstream of a bleached kraft pulp mill in Ontario. Fish for the study were collected in two different years, before and after the pulp mill undertook a number of improvements to eliminate the release of process chemicals. Results showed a 3.4-fold increase in ovarian cell apoptosis in growing white sucker collected four km downstream of the bleached kraft pulp mill in 1996 (before the improvements) compared to fish collected from upstream sources. The elevated ovarian cell apoptosis was associated with significant reduction in gonadosomatic index in fish collected downstream. There were no differences in ovarian cell apoptosis or gonadosomatic index between fish collected upstream and four km downstream of the mill in September 1998 (after the improvements.) Based on the results, it may be concluded that chronic stimulation of ovarian cell apoptosis by certain components of bleached kraft pulp mill effluents represents an important cellular mechanism for reducing the size of ovaries and other related reproductive responses in female fish exposed to these effluents. Although the specific effluent components are not known, the improvements undertaken between 1996 and 1998 resulted in significant enough recovery of these responses to justify the belief in a cause-effect relationship. 32 refs., 1 tab., 2 figs.

  10. Papaya pulp gelling: is it premature ripening or problems of water accumulation in the apoplast?

    Directory of Open Access Journals (Sweden)

    Jurandi Gonçalves de Oliveira

    2010-12-01

    Full Text Available Gelled aspect in papaya fruit is typically confused with premature ripening. This research reports the characterization of this physiological disorder in the pulp of papaya fruit by measuring electrolyte leakage, Pi content, lipid peroxidation, pulp firmness, mineral contents (Ca, Mg and K - in pulp and seed tissues, and histological analysis of pulp tissue. The results showed that the gelled aspect of the papaya fruit pulp is not associated with tissue premature ripening. Data indicate a reduction of the vacuole water intake as the principal cause of the loss of cellular turgor; while the waterlogged aspect of the tissue may be due to water accumulation in the apoplast.

  11. KRAFT PULPING CHARACTERISTICS OF THREE MOROCCAN EUCALYPTI. PART 1. PHYSICAL AND CHEMICAL PROPERTIES OF WOODS AND PULPS

    OpenAIRE

    Mohammed El Moussaouiti,; Badr. Barcha,; Ericka F. Alves,; Raymond C. Francis

    2012-01-01

    Two eucalyptus hybrids (EGC 39, EGC 241), resulting from crosses between Eucalyptus grandis and Eucalyptus camaldulensis, were investigated to see if they could produce kraft papermaking fibers with low lignin and adequate physical properties. The two hybrids were harvested at an age of 8 years along with 6-8 year old Eucalyptus camaldulensis (Rostrata). All three eucalypti were grown in the area of Gharb in the North-West of Morocco. The tracheids in the two hybrids had a very high Runkel ra...

  12. A comparison of kraft, PS, kraft-AQ and kraft-NaBH4 pulps of Brutia pine.

    Science.gov (United States)

    Copur, Y; Tozluoglu, A

    2008-03-01

    The aim of this work was to study the effect of adding PS, AQ and NaBH(4) into kraft pulping with special attention given to NaBH(4). Kraft, kraft-AQ, PS, and kraft-NaBH(4) pulps were produced under the same cooking conditions and the pulps produced were compared in terms of pulp and paper properties. Kraft method was modified by adding 0.1% AQ, 4% PS and 2% and 4% NaBH(4) and the resultant pulps displayed an increase in pulp yield and reduction in both kappa number and screening rejects. On the other hand, there observed an increase in both pulp yield and kappa number when the kraft was modified to PS method. The benefits of NaBH(4) addition into kraft pulping was a significant reduction in kappa number and screening rejects and a significant increase in pulp yield. The most notable outcome of NaBH(4) was 66.6% increase in pulp brightness when 4% NaBH(4) was added into kraft pulping. Of unrefined pulps, unrefined kraft pulp displayed the highest strength of pulp, which is described as tear index at a constant tensile index. Of refined pulps, kraft-AQ showed the highest pulp strength when refined to 6000 and 12,000 revs in PFI mill. PMID:17531474

  13. Permittivities of watermelon pulp and juice and correlation with quality.

    Science.gov (United States)

    Permittivities from 10 to 4500 MHz at 24 'C were measured on pulp and juice of watermelons of different maturities with an open-ended coaxial-line probe and network analyzer. The dielectric constant of both materials decreased monotonically with increasing frequency and loss factor had minimum at ab...

  14. Fatty acids profile of pulp and nuts of Brazilian fruits

    Directory of Open Access Journals (Sweden)

    Paulo Afonso da Costa

    2011-12-01

    Full Text Available Fruits and nuts from the North and Northeast regions of Brazil were collected to determine the fatty acid profile of their oils. The species studied were Brazil (Bertholletia excelsa H.B.K., Mucajá (Couma rigida M., Inajá (Maximiliana maripa D., Jenipapo (Genipa Americana L., and Buriti (Mauritia flexuosa L. nuts. Fatty acid methyl esters were analyzed by gas chromatography with flame ionization detection (GC-FID. Brazil nut major fatty acid was 18:3n-3 (α-linolenic acid, and Buriti nut had approximately 23 times more 18:3n-3 than the pulp. Mucajá nut presented high content of 12:0 (lauric acid and 16:0 (palmitic acid, and Mucajá pulp showed significant levels of 18:2n-6 (linoleic acid. Considering the PUFA (polyunsaturated fatty acid sum values, almost all fruits and nuts analyzed presented very high levels of these compounds. Regarding n-6/n-3 ratio, only Brazil Nut, Buriti Nut, Inajá pulp, and Jenipapo pulp corresponded to the desired profile. These Brazilian fruits and nuts could be of potential interest due to their high nutritive value and lipid content.

  15. Role of tissue engineering in dental pulp regeneration

    Directory of Open Access Journals (Sweden)

    Shruti Sial

    2012-01-01

    Full Text Available Stem cells constitute the source of differentiated cells for the generation of tissues during development, and for regeneration of tissues that are diseased or injured postnatally. In recent years, stem cell research has grown exponentially owing to the recognition that stem cell-based therapies have the potential to improve the life of patients with conditions that span from Alzheimer′s disease to cardiac ischemia to bone or tooth loss. Growing evidence demonstrates that stem cells are primarily found in niches and that certain tissues contain more stem cells than others. Among these tissues, the dental pulp is considered a rich source of mesenchymal stem cells that are suitable for tissue engineering applications. It is known that dental pulp stem cells have the potential to differentiate into several cell types, including odontoblasts, neural progenitors, osteoblasts, chondrocytes, and adipocytes. The dental pulp stem cells are highly proliferative. Collectively, the multipotency, high proliferation rates, and accessibility make the dental pulp an attractive source of mesenchymal stem cells for tissue regeneration. This review discusses fundamental concepts of stem cell biology and tissue engineering within the context of regenerative dentistry.

  16. Use of coffee pulp as feed ingredient for tilapia culture

    NARCIS (Netherlands)

    Ulloa Rojas, J.B.

    2002-01-01

    This research focused on the feasibility of using coffee pulp (CoP) in diets for tilapia ( Oreochromis aureus ). First, a literature survey analyzed the limitations of CoP as an animal foodstuff (several antinutritional factors: ANF's, and high fibre contents), different ways to upgrade the CoP nutr

  17. IMPACT OF COOKING HOMOGENEITY ON PULP STRENGTH PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    BofengMao

    2004-01-01

    Cooking homogeneity of kraft pulping can havesignificant impact on pulp strength properties. Wehave studied cooking homogeneity of two kraftdigesters within Stora Enso. One of the digesters is aone-vessel hydraulic continuous digester (digester A)and the other one is a two-vessel vapor/liquor phasecontinuous digester (digester B). They are located inthe same mill and use the same softwood chipquality. Due to the differences in chip pre-steamingand cooking facilities and conditions, significantdifferences in pulp strength properties, reject contentsand kappa variations have been found between thepulps produced in the two digesters. Digester A has amodem chip bin with efficient pre-heating and airremoval, whereas digester B has poor chippre-steaming conditions. Our strength deliverystudies show that although the two digesters producepulps with the same kappa number and viscosity, thepulp produced in digester A has about 20% higherstrength delivery, l%-unit (based on wood) lowerreject content and lower kappa variations based onFTIR spectra analysis on pulp sheet than the pulpproduced in digester B.Results of the studies indicate that morehomogeneous cooking,variation in the fibers,i.e., lower lignin/kappa leads to improved pulpstrength properties. Efficient chip pre-steaming isimportant/essential for achieving homogeneouscooking. Rebuilding the equipment for improvingchip pre-steaming conditions of digester B is to becarded out.

  18. WHY COMT-DEFICIENT PLANTS HAVE POOR PULPING PERFORMANCE

    Science.gov (United States)

    Transgenic plants that have reduced lignin content, or structurally or compositionally modified lignins, have been studied in order to identify traits with excellent pulping performance. COMT is an enzyme in the monolignol pathway crucial to the synthesis of sinapyl alcohol, one of the two major mon...

  19. Research on Effect of Magnetized Pulp on Coal Slime Flotation

    Institute of Scientific and Technical Information of China (English)

    边炳鑫; 肖健丽; 陈清如; 韦鲁滨

    2004-01-01

    Effect of magnetization on oxygen concentration, pH, surface zeta potential, and wet heat of flotation pulp were researched. The result shows that magnetization treatment can improve the floatablility of coal and increase the difference in wet heat among coal, refuse, and pyrite, which is favorable for slime flotation and for removing sulfur and ash from coal.

  20. Recuperation of uranium and gold in mineral pulps by adsorption

    International Nuclear Information System (INIS)

    The technological routes for the treatment of the gold and uranium ores are presented. The results obtained during the continuous tests with the uraniferous Ores of Wabo in Somalia are presented. The utilization of 99% of the uranium content in the alkaline pulp is obtained. (C.B.)

  1. Antimicrobial and Antioxidant Activity of Fruit Pulp of Livistonia Chinensis

    OpenAIRE

    Tanu P; Thakur K; Kaur G

    2013-01-01

    The present study reveals the in-vitro antimicrobial activity and antioxidant activity of ethanolic extractof fruit pulp of plant of Livistonia chinensis has been evaluated using disc diffusion method againstbacterial strains of Bacillus subtilis, Staphylococcus aureus, Shigella dysenteriae, Salmonella enteritidisand fungal strain of Candida albicans using specific standard Ciprofloxacin and Fluconazolerespectively and DPPH method for antioxidant activity.

  2. Effect of gamma radiation from 60C in conservation and quality of pepper fresh and pulp

    International Nuclear Information System (INIS)

    Capsicum peppers are among the most used and most valued seasoning spices in the world. They are highly susceptible to post harvest decay, therefore the use of irradiation may contribute to conservation of this fruit which has significant nutritional, economic and social value. Were evaluated the effects of gamma radiation of 60Co in increasing the shelf-life and preservation of quality of pepper 'Dedo-de-moca' (Capsicum baccatum var. Pendulum) fresh and pulp associated or not with another conservation methods. Gamma radiation doses were investigated of 0,25; 0,50; 0,75; 1,00; 1,25; 1,50; 2,00 e 3,00 kGy in fresh fruit and 1,50; 2,00; 3,00; 4,50 e 6,00 kGy in pepper pulp. The use of laboratory pasteurization (85°C/3min), the addition of citric acid (5%) and 5% NaCl were also investigated in the pepper pulp. The samples were stored at 5 °C and or 25 °C. Were performed analysis: visual (disease incidence, turgidity and color); bioactive compounds (carotenoids, capsaicinoids, antioxidant capacity and phenolic compounds); physicochemical (Weight loss, firmness, soluble solids (SS), pH, titratable acidity (TA), ratio, color and moisture); respiratory rate and ethylene production; proximate composition (moisture, soluble and insoluble fiber, ash, protein, ether extract, total and available carbohydrate); microbiological contamination (mesophilic aerobic microorganisms, coliforms at 45 °C, Salmonella spp. and yeasts and molds) and sensory (acceptance test, difference test and paired preference). Radiation doses between 0.25 and 3.00 kGy were not effective to increase shelf-life and maintain fresh pepper quality during storage. There was increased intensity of red color, of incidence of disease, decreased turgidity and changes in physical, chemical and nutritional parameters. In pulp, the doses of gamma radiation of 4.50 and 6.00 kGy and the addition of 5% NaCl no changing sensory attributes, physical-chemical and bioactive compounds. Only the antioxidant

  3. Comparative study of lipophilic extractives of hardwoods and corresponding ECF bleached kraft pulps

    Directory of Open Access Journals (Sweden)

    Pascoal Neto, C.

    2006-07-01

    Full Text Available The lipophilic extractives of Eucalyptus globulus , Eucalyptus grandis , Eucalyptus urograndis , Betula verrucosa and Acacia mangium woods and of the corresponding ECF bleached kraft pulps, were characterised by GC-MS. The five hardwoods showed significant differences in the content and composition of the main families of extractives, namely fatty acids, long chain aliphatic alcohols and sterols. Significant differences in the composition persist after wood pulping and ECF bleaching of pulps. The fate of the various types of extractives during the wood and pulp processing is discussed. Long chain aliphatic acids and alcohols are quite stable during the pulp production and are retained to a great extent in the final bleached pulp; delta 5 sterols are mostly oxidised and partially retained in the pulps, while delta 7 sterols are completely degraded and/or dissolved. B. verrucosa and A. mangium bleached pulps show contents of fatty acids about 4 and 20 times higher than that of Eucalyptus pulps, respectively, while the content of long chain aliphatic alcohols in A. mangium pulp is of the order of 100 times higher than Eucalyptus and B. verrucosa pulps.

  4. Human tooth pulp anatomy visualization by 3D magnetic resonance microscopy

    International Nuclear Information System (INIS)

    Precise assessment of dental pulp anatomy is of an extreme importance for a successful endodontic treatment. As standard radiographs of teeth provide very limited information on dental pulp anatomy, more capable methods are highly appreciated. One of these is 3D magnetic resonance (MR) microscopy of which diagnostic capabilities in terms of a better dental pulp anatomy assessment were evaluated in the study. Twenty extracted human teeth were scanned on a 2.35 T MRI system for MR microscopy using the 3D spin-echo method that enabled image acquisition with isotropic resolution of 100 μm. The 3D images were then post processed by ImageJ program (NIH) to obtain advanced volume rendered views of dental pulps. MR microscopy at 2.35 T provided accurate data on dental pulp anatomy in vitro. The data were presented as a sequence of thin 2D slices through the pulp in various orientations or as volume rendered 3D images reconstructed form arbitrary view-points. Sequential 2D images enabled only an approximate assessment of the pulp, while volume rendered 3D images were more precise in visualization of pulp anatomy and clearly showed pulp diverticles, number of pulp canals and root canal anastomosis. This in vitro study demonstrated that MR microscopy could provide very accurate 3D visualization of dental pulp anatomy. A possible future application of the method in vivo may be of a great importance for the endodontic treatment

  5. Isolation and characterization of pulp from sugarcane bagasse and rice straw

    International Nuclear Information System (INIS)

    The amount of sugarcane bagasse and rice straw in the state of Perlis (Malaysia) is abundant while its utilization is still limited. One of the alternatives for the bagasse and straw utilization is as pulp raw material. This paper reviews on pulp from sugarcane bagasse and rice straw and its suitability for paper production. In this study, the pulp was extracted by the Soxhlet extraction method. The objective of this study was to investigate the cellulose, lignin and silica content of the pulp from sugarcane bagasse and rice straw. For rice straw, the presence of large amount of pentosanes in the pulp and black liquors, which also contain silica were decreased the using of straw in the paper industry. Therefore, formic acid pulping and NaOH treatment are studied to reduce or prevent silica. The isolated pulp samples were further characterized by Scanning Electron Microscope (SEM) to investigate their fiber dimensions. (Author)

  6. Dentin Sialophosphoprotein-derived Proteins in the Dental Pulp.

    Science.gov (United States)

    Yamamoto, R; Oida, S; Yamakoshi, Y

    2015-08-01

    Porcine dentin sialophosphoprotein (DSPP), the most abundant noncollagenous protein in dentin, is critical for proper mineralization of tooth dentin. DSPP is processed by proteases into 3 major domains: dentin sialoprotein (DSP), dentin glycoprotein (DGP), and dentin phosphoprotein (DPP). There are at least 2 mRNA variants expressed from the Dspp gene: one encodes the full-length DSPP protein (DSP+DGP+DPP); the other encodes only DSP. The shorter transcript is generated through the use of a polyadenylation signal within intron 4, immediately following the DSP coding region (DGP and DPP are encoded by exon 5). We fractionated DSPP-derived proteins from the dental pulp of developing porcine incisors using heparin chromatography. DSP was identified, but little DPP could be detected in any fractions. BMP-1 digestion of DSPP-derived proteins extracted from dental pulp did not generate new DPP bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (indicating an absence of intact DSPP), although the results suggested another BMP-1 cleavage site within DSP. We further purified DSPP-derived protein by reversed-phase high-performance liquid chromatography. Its amino acid composition was similar to DSP. Expression of the full-length Dspp mRNA by quantitative real-time polymerase chain reaction analysis was significantly higher in odontoblasts than in pulp, while expression of the DSP-only mRNA was almost equal in odontoblasts and in the body of the pulp. Expression of the full-length Dspp mRNA was also significantly higher than the expression of DSP-only mRNA in odontoblasts. Both the full-length and the DSP-only Dspp mRNA showed only trace expression in the pulp tip. We conclude that use of the 3' polyadenylation signal in exon 5 predominates in fully differentiated odontoblasts, while both polyadenylation signals are used throughout odontoblast differentiation. PMID:25951824

  7. CRITERIA SELECTION FOR BLEACHED EUCALYPT KRAFT PULP SPECIFICATION ORIENTED TO THE MANUFACTURE OF OFFSET PAPERS

    Directory of Open Access Journals (Sweden)

    Edison da Silva Campos

    2009-09-01

    Full Text Available The purpose of this work was to analyze the characteristics of some eucalypts pulps available in the market, aiming to understand their influence in the properties of the offset papers. Another objective of this work was to show alternatives to reduce the number of laboratory tests in the pulp specifications. Thirteen (13 market pulps (Brazilian and international pulps were analyzed and the tests applied were as follows: intrinsic viscosity, alkali solubility at 5%, coarseness, numbers of fibers per gram of pulp, average length of fibers, fine fraction by the Dynamic Paper Chemistry Jar (DPCJ, drainability by Schopper Riegler, before refining. Other tests, such as: tensile index, stretch, burst index, tear index, bulk, air resistance, opacity and absorption of water by cappilarity (Klemm were performed for each type of pulp before refining and for refining levels of 25 ºSR, 30 ºSR, 40 ºSR and 55 ºSR. No evidence of the influence of S5 and intrinsic viscosity was observed at the range of the market pulp properties variation. The Brazilian pulps presented higher initial drainability and required lower PFI revolutions to the same level of refining in comparison to the international pulps. The initial average values of strength indexes: tensile, stretch, burst and tear were higher to the Brazilian pulps. However, this situation was changed at 25 ºSR and other levels of drainability. Due to the higher number of correlations at 30 ºSR, this level of drainability was chosen to determine the pulp characteristics profile. At this level, international pulps showed better values of tensile and tear index, but a higher energy consumption and a lower opacity in comparison to the Brazilian pulps. In addition, this paper  suggested the concentration of the lab technical evaluation of pulps on the analysis of opacity, tensile and tear indexes. Such procedure should reduce the number of lab tests as well.

  8. Pulp and plaque microbiotas of children with severe early childhood caries

    Directory of Open Access Journals (Sweden)

    Natalia I. Chalmers

    2015-02-01

    Full Text Available Background and objective: Bacterial invasion into pulps of primary teeth can lead to infection and premature tooth loss in children. This pilot study aimed to explore whether the microbiota of carious exposures of dental pulps resembles that of carious dentin or that of infected root canals. Design: Children with severe early childhood caries were studied. Children were consented and extent of caries, plaque, and gingivitis measured. Bacteria were sampled from carious lesion biofilms and vital carious exposures of pulps, and processed by anaerobic culture. Isolates were characterized from partial sequences of the 16S rRNA gene and identified by comparison with taxa in the Human Oral Microbiome Database (http://www.HOMD.org. The microbiotas of carious lesions and dental pulps were compared using univariate and multivariate approaches. Results: The microbiota of cariously exposed pulps was similar in composition to that of carious lesion biofilms except that fewer species/taxa were identified from pulps. The major taxa identified belonged to the phyla Firmicutes (mainly streptococci and Actinobacteria (mainly Actinomyces species. Actinomyces and Selenomonas species were associated with carious lesions whereas Veillonella species, particularly Veillonella dispar was associated with pulps. Other bacteria detected in pulps included Streptococcus mutans, Parascardovia denticolens, Bifidobacterium longum, and several Lactobacillus and Actinomyces species. By principal, component analysis pulp microbiotas grouped together, whereas those in caries biofilms were widely dispersed. Conclusions: We conclude that the microbiota of cariously exposed vital primary pulps is composed of a subset of species associated with carious lesions. Vital primary pulps had a dominant Firmicutes and Actinobacteria microbiota which contrasts with reports of endodontic infections which can harbor a gram-negative microbiota. The microbiota of exposed primary pulps may provide

  9. PHYTOCHEMICAL AND ANTIMICROBIAL PROPERTIES OF SEED AND PULP OF MONKEY COLA ( Cola millenii ON SOME SELECTED CLINICAL AND FOOD BORNE ISOLATE

    Directory of Open Access Journals (Sweden)

    Giwa O. E

    2012-08-01

    Full Text Available The phytochemical analyses of pulp and seed of Cola milleniiK. Sckhum showed that the extractcontained alkaloids, tannins, saponins, cardiac glycosides, carbohydrate, sterol, resin and terpenes that could beresponsible for the observed antimicrobial activities. The bioactives compounds of pulp and seed extract of ColamilleniiK. Sckhum were extracted, using both aqueous (water and organic (ethanol solvents, and wereinvestigated for antimicrobial activity some pathogenic and food spoilage microorganisms using agar welldiffusion method. The aqueous extract did not show significant difference in their activities against the variousorganisms but the ethanolic extract had a significant activity demonstrating the highest activity against the testorganisms using analysis of variance p<0.05. The seed extract demonstrated higher activity against both the grampositive and gram negative organisms tested, and also against the selected test fungi with the highest activity(1.73±0.06 cm zone of inhibition against Aspergillusniger. The minimum inhibitory concentration (MIC andminimum bactericidal/ fungicidal concentration (MBC/MFC of the extract ranges between 40-160 mg/ml forboth the seed and pulp of the plant. The antimicrobial property shown by the plant extract is an evidence of theethno-medicinal uses of the plant. Cola millenii seed and pulp bioactive content may therefore be extracted anduse as antibiotics and/or preservative in foods as the result is comparable with commercially available antibioticsand chemical preservatives.

  10. 全棉杆氧化法清洁制浆的可行性研究%Feasibility Study of Cotton Stalk Oxidation Clean Pulping

    Institute of Scientific and Technical Information of China (English)

    黄晓梅; 苏晓军

    2012-01-01

    详细介绍了利用氧化法清洁技术制浆的工艺原理和生产工艺流程。该技术从根本上改变了传统制浆技术的机理,彻底消除了碱、氯、蒽醌等化学品对环境造成的污染,从源头上根除了制浆行业的污染,从根本上解决了制浆黑液(或红液)污染和纺织行业废水污染的世界性难题。%This paper introduced the process principles and production process of oxidation clean technologies pulping.The technology fundamentally changed the mechanism of conventional pulping technology,and completely eliminated pollution caused by the alkali,chlorine, anthraquinone and other chemicals on the environment.The pulp industry pollution was eradicated from the source.The technology fundamentally solved the pulp worldwide problem of black liquid (or red liquid) pollution and the textile industry wastewater pollution.

  11. Microscopic analysis of dog dental pulp after pulpotomy and pulp protection with mineral trioxide aggregate and white Portland cement Análise microscópica da polpa dental de cães após pulpotomia e proteção pulpar com agregado de trióxido mineral e cimento Portland branco

    Directory of Open Access Journals (Sweden)

    Renato Menezes

    2004-06-01

    Full Text Available Considering previous studies on the similarity between the chemical composition of the mineral trioxide aggregate and the Portland cement, the purpose of this study was to investigate the pulp response of dog's teeth after pulpotomy and direct pulp protection with MTA Angelus and white Portland cement. Thirty eight pulp remnants were protected with these materials. One hundred and twenty days after treatment, the animals were sacrificed and the specimens removed and prepared for histological analysis. Both materials demonstrated the same results when used as pulp capping materials, inducing hard tissue bridge formation and maintaining pulp vitality in all specimens. The MTA Angelus and the white Portland cement showed to be effective as pulp protection materials following pulpotomy.Considerando estudos anteriores sobre a similaridade entre a composição química do agregado de trióxido mineral e o cimento Portland, o objetivo deste estudo foi investigar a resposta pulpar de dentes de cães após pulpotomia e proteção pulpar direta com MTA Angelus e cimento Portland branco. Trinta e oito remanescentes pulpares foram recobertos com esses materiais. Cento e vinte dias após o tratamento, os animais foram sacrificados e os espécimes removidos e preparados para análise histológica. Ambos os materiais demonstraram os mesmos resultados quando utilizados como materiais de capeamento pulpar, induzindo a formação de ponte de tecido mineralizado e mantendo a vitalidade pulpar em todos os espécimes. Ambos matérias se mostraram efetivos como protetores pulpares após pulpotomia em dentes de cães.

  12. Preparation nanowhiskers pulp from residue of palm fiber Attalea funifera Martius

    International Nuclear Information System (INIS)

    The residue from piassava fiber is higher in cellulose and lignin. This study aimed to extract the pulp and the development of methodology for preparation nanowhiskers from residue fiber. The first step extraction of cellulose, the second step to obtain the nanoparticles by acid hydrolysis (H2SO4). The samples were characterized by: SEM, chemical composition, TGA, FTIR and XRD. The XRD result shows that cellulose is of type I and TGA shows two events at 54 deg C and 370 deg C attributed to mass loss of water and cellulose, respectively. After hydrolysis, X-ray diffraction showed an intense reflection 2θ= 22.3 deg and an increase in the degree of crystallinity to 70% which is an indication of the formation of nanowhiskers. (author)

  13. Combination of coagulation and catalytic wet oxidation for the treatment of pulp and paper mill effluents.

    Science.gov (United States)

    Verenich; Laari, A; Nissen, M; Kallas, J

    2001-01-01

    Wet oxidation (WO) is a well established process for purification of concentrated municipal and industrial wastewaters. Many attempts have been made to modify the WO process or to create a suitable combination of processes. This work was undertaken to investigate wet oxidation integrated with coagulation, i.e. to treat the sludge remaining after coagulation with a WO process. The possibility of regeneration of the used coagulant was also considered. Two waters from paper mills were used: TMP (thermomechanical pulp) circulation water and membrane concentrate. About 50% of the COD in the original water can be removed by coagulation using Fe2(SO4)3. The results from the wet oxidation experiments show the positive effect of iron in the chemical sludge as a catalyst. The efficiency of the WO process was enhanced almost by 100%. The remaining dissolved organic matter can be easily removed biologically. PMID:11695452

  14. Environmental Assessment of Enzyme Assisted Processing in Pulp and Paper Industry

    DEFF Research Database (Denmark)

    Skals, Peter B; Krabek, Anders; Nielsen, Per Henning;

    2008-01-01

    discusses the environmental potential of a range of other enzyme applications  by qualitative means. LCA is used as analytical tool and modelling is facilitated in SimaPro software. Foreground LCA data are production/ company specific and collected from P&P technology service providers, specific P...... improvements that can be achieved by application of enzymatic solutions in the P&P industry are  promising. To get a greater penetration of enzymatic solutions in the market and to harvest the environmental advantages of biotechnological inventions, it is recommended that enzymatic solutions should be given......The pulp and paper (P&P) industry is traditionally known to be a large contributor to environmental pollution due its large consumptions of energy and chemicals. Enzymatic processing, however, offers potential opportunities for changing the industry towards more environmentally friendly and...

  15. Histological evaluation of direct pulp capping by using of calcium hydroxide and octacalcium phosphate in cats dental pulp

    Directory of Open Access Journals (Sweden)

    Eshagh Ali Saberi

    2013-08-01

    Full Text Available   Background and Aims: The purpose of this study was to evaluate the tissue responses to octacalcium phosphate (OCP and calcium hydroxide (CH used as direct pulp capping (DPC materials in cat teeth.   Materials and Methods: 72 premolar teeth of 9 cats were selected and divided into 3 groups (Two experimental and one control group. After the cats had been anesthetized, the pulp were exposed and capped directly with OCP, CH or no capping material as control group. The cavities of all three groups were filled with Glass ionomer cement (GI. Histological evaluations were performed at two, four and eight weeks after pulp capping. After tissue preparation procedures, paraffin blocks were prepared. After preparation and staining of the sections, the relevant variables were measured by optical microscope. The results were analyzed using Mann-Whitney U and Chi-square tests ( α =0.05.   Results: Two weeks after pulp capping, all specimens in three groups showed mild to sever inflammation. The formation of hard tissue (dentinal bridge at in the exposed areas of the experimental groups was more noticeable for calcium hydroxide than that of octacalcium phosphate group. These differences were statistically significant (P<0.001. At four weeks, hard tissues were observed in both groups which were more evident for the CH group and there were statistically significant difference between two experimental groups (p0.05, but hard tissues continuity were better for in the OCP than that of the CH.   Conclusion: It seems that the formation of hard tissue in CH because of its porosities had a worse percentage in sealing of the pulp than the OCP .

  16. Changes in the physicochemical and microbiological properties of frozen araça pulp during storage

    Directory of Open Access Journals (Sweden)

    Clarissa Damiani

    2013-02-01

    Full Text Available Araça belongs to the Myrtaceae family and is popularly known as araçá-comum, araçá-azedo, or araçá-do-campo. Frozen fruit pulp is of great importance for the food industry, which can produce it at the time of harvest, store it, and use it according to the demand of the consumer market and/or as an ingredient in the formulation of products such as yogurt, candies, and ice creams among others. The aim of this study was to evaluate the physical, chemical, and microbiological stability of frozen araça pulp during 12 months of frozen storage. It was observed that the levels of moisture (90.55-88.75%, ash (0.34-0.26% total soluble sugars (7.11-6.62%, sucrose (3.55-1.39%, soluble pectin (0.24-0.23%, total pectin (0.5-0.46%, pH (3.82-2.31%, organic acids (698.12-122.25 µg.g-1 citric acid, and phenolic compounds (6.22-0.00 mg GAE.100 g-1 decreased during storage, whereas the levels of protein (0.61-0.83%, lipids (0.14-0.38%, total carbohydrates (8.36-9.78%, calorific value (37.14-45.86 kcal.100 g-1, reducing sugars (3.51-5.21%, soluble solids (5.17-6.0%, total antioxidant capacity (6.89-35.13%, and color parameters (L*49.75-50.67; a*0.79-1.82 and b*22.5-25.19 increased over the one-year storage period. According to the chemical and microbiological parameters assessed, the product can be stored for 12 months without loss of quality with addition of citric acid as a preservative.

  17. Indirect pulp capping in primary molar using glass ionomer cements

    Directory of Open Access Journals (Sweden)

    Murtia Metalita

    2014-12-01

    Full Text Available Background: Indirect pulp capping in primary teeth, however, is more rarely conducted than permanent teeth, since it thought to have low impact and most suggestion is for taking caries lesion aggressively on primary teeth. Purpose: The study was aimed to evaluate the subjective complaint, clinical symptom, and radiographic appearance of indirect pulp capping treatment using glass ionomers cements in primary molar. Methods: Sixteen children in range of age 6 to 8 years old, who visited Clinic of Pediatric Dentistry Universitas Airlangga Dental Hospital, Surabaya Indonesia, were the subject of study. They had one occlusal dental caries on one side of maxillary or mandibular primary molar with the diagnose of pulpitis reversible. The experimental group, had indirect pulp capping treatment with glass ionomer cements (GC Fuji VII®, while the control group, had indirect pulp capping treatment with calcium hydroxide (Metapaste. Each group was filled with GC Fuji IX® as permanent restoration. After one week, one month, and three months later, the observations were made on subjective complaint, clinical symptom, and radiographic appearance. Results: The results showed no subjective complaint such as pain or problem on mastication; no negative clinical symptoms such as pain on palpation, gingivitis or periodontitis, and abnormal tooth mobility; no negative radiographic appearance such as pathological apical radioluscency, internal or external resorbtion, and change of ligament periodontal widthafter the treatment. Conclusion: The study suggested that indirect pulp capping treatment using glass ionomer cement materials on primary teeth might be considered to be the treatment choice.Latar belakang: Indirect pulp capping pada gigi sulung lebih jarang dilakukan dibandingkan gigi permanen, karena dianggap memiliki dampak yang rendah dan sebagian besar menyarankan untuk mengambil lesi karies secara agresif pada gigi sulung. Tujuan: Penelitian ini bertujuan

  18. Quality assessment of fruit pulps industrialized and commercialized in the city of Boa Vista – RR = Avaliação da qualidade de polpas de frutos industrializadas e comercializadas no município de Boa Vista – RR

    OpenAIRE

    Cássia Rejane Nascimento; Leandro Camargo Neves; Maria Luiza Grígio; André José de Campos; Edvan Alves Chagas; Ataiza de Andrade Souza

    2012-01-01

    This work aimed to study the quality of frozen pulp, manufactured and marketed in Boa Vista - RR, through physico-chemical analysis. It were selected six Agroindustries that produce and market pulp in establishments located in Fair Passarão, supermarkets and home of juices, identified by the letters A, B, C, D, E and F. The variables studied were: soluble solids, titratable acidity and vitamin C, of the flavors: acerola, caja, cupuaçu, guava, soursop and passion fruit. The experiment was con...

  19. A influência do pH na reologia de polpas de caulim The influence of pH on the rheology of kaolin pulps

    Directory of Open Access Journals (Sweden)

    Fabíola Oliveira da Cunha

    2007-09-01

    Full Text Available Polpas concentradas de caulim são amplamente utilizadas na indústria química. Algumas aplicações da polpa exigem altas taxas de cisalhamento, que, associadas às altas viscosidades de polpas concentradas, provocam dificuldades na sua utilização como cobertura. Para minimizar esse efeito, ajusta-se o pH e adicionam-se agentes dispersantes à polpa. O presente trabalho teve por finalidade analisar a influência do pH na polpa do caulim Coat 90 produzido na região do Prado/BA, contribuindo para a melhor compreensão dos mecanismos de interação solvente/mineral na reologia de polpas através dos fundamentos da química coloidal. Visando a alcançar esses objetivos, foram efetuados ensaios de potencial zeta e reológicos; foi aplicada a teoria DLVO clássica aos resultados obtidos. A análise dos dados revelou que as polpas possuem comportamento tixotrópico em valores de pH correspondentes a meios neutros e /ou alcalinos; a viscosidade aparente das polpas, em uma mesma taxa de cisalhamento e em um mesmo intervalo de tempo, primeiramente apresentam decréscimo com o aumento do pH e, posteriormente, a partir de determinado valor de pH, há a sua estabilização; por outro lado, existe um valor de energia total de interação, a partir do qual um grau máximo de estabilidade /dispersão é conferido à polpa.Concentrated kaolin pulps are utilized as coatings in the chemical industry. During pulp application, high shear rates are obtained. Elevated shear rates associated to high viscosities incite difficulties on the lamina movement generating risks, bubbles or even tearing the paper. To minimize this effect pH adjustment and addition of dispersant agents to the pulp are made. The aim of this work was to study the colloidal behavior of the Coat 90 Prado region (Bahia State kaolin pulps, through zeta potential and rheological evaluations combined with the classical DLVO theory. The data analysis showed that the pulps presented thixotropic

  20. ABSORBENT MATERIALS BASED ON KRAFT PULP: PREPARATION AND MATERIAL CHARACTERIZATION

    Directory of Open Access Journals (Sweden)

    Fredrik Wernersson Brodin,

    2012-02-01

    Full Text Available Today, petroleum-based superabsorbents are widely used, but interest in renewable alternatives is on the rise. This study presents two wood-based absorbent materials suitable for various absorption applications as an alternative to petroleum-based products. Never-dried bleached kraft pulp was treated with TEMPO-oxidation, and new carboxylate and aldehyde groups were introduced. It was found that the aldehyde groups contributed to the wet integrity of the absorbent materials, possibly by the formation of hemiacetal bonds. After oxidation, the pulp fibers were gradually disintegrated, and size analysis showed that the disintegration rate was enhanced by an increase in the charge of the oxidant. Freeze drying produced a porous foam with a large surface area that enabled a rapid absorption rate as well as a reasonably high absorption capacity even for absorption under load. Air drying formed a compact film with a slow absorption rate but with a high final capacity for absorption.

  1. Dental pulp vascular permeability changes induced by dental bleaching

    Directory of Open Access Journals (Sweden)

    Cristiane da Costa

    2012-02-01

    Full Text Available Aiming to compare the effect of different light sources for dental bleaching on vascular permeability of dental pulps, forty-eight incisors were used. The bleaching agent (35 % hydrogen peroxide was activated by halogen light; LED (Light Emitting Diode or LED, followed by laser phototherapy (LPT (λ = 780 nm; 3 J/cm². After the bleaching procedures, the animals received an intra-arterial dye injection and one hour later were sacrificed. The teeth were diaphanized and photographed. The amount of blue stain content of each dental pulp was quantified using a computer imaging program. The data was statistically compared (p < 0.05. The results showed a significant higher (p < 0.01 dye content in the groups bleached with halogen light, compared with the control, LED and LED plus LPT groups. Thus, tooth bleaching activated by LED or LED plus LPT induces lesser resulted in increased vascular permeability than halogen light.

  2. Flow behavior and physicochemical characterization of peach pulps

    Directory of Open Access Journals (Sweden)

    Ernesto Muñoz Puntes

    2012-06-01

    Full Text Available Rheological and physicochemical analyses were conducted on nine varieties of peach pulps from Mendoza (Argentina at a range of soluble solids concentration (12.5 to 28°Brix and temperatures (30 to 50°C.The rheology of the pulps followed the power law model for all conditions, behaving as pseudoplastic fluids. Rheological: consistency coefficient and flow behavior index, using a rotational type viscometer and physicochemical parameters (methods proposed by AOAC: soluble solids, pH, water content, insoluble solids, acidity and pectin content (refractometric method were determined in this study. Cluster analysis established two groups (1: Halford, Andross, Astengo, Bowen, Sim’s Cling; 2: Fortuna, Loadel and Palora; Sullivan Cling variety could not be assigned to any group with significant differences.

  3. Pulp microbiology of complete teeth with idiopathic apical lesions.

    OpenAIRE

    Patricia Rodríguez; Jesús Alberto Calero

    2009-01-01

    Introduction: Periapical changes named as lesions, in teeth with full crown integrity and without history of trauma, do not show a clear aetiology. Objective: To determine the presence of microorganisms in pulp dental tissue will clarify the cause of its death and therefore the damage to periodontal tissues. Materials and methods: From people between 10 and 39 years old, 23 teeth were selected. The samples were taken with paper points and 0.8 sterile files, and were transported in VMGA III me...

  4. Dietary citrus pulp reduces lipid oxidation in lamb meat

    OpenAIRE

    Inserra, L.; Priolo, A.; L. Biondi; Lanza, M.; Bognanno, M.; Gravador, R.; Luciano, G.

    2014-01-01

    This study investigated the effect of replacing cereal concentrateswith high levels of dried citrus pulp in the diet on lamb meat oxidative stability. Over 56 days, lambs were fed a barley-based concentrate (Control) or concentrates inwhich 24% and 35% dried citrus pulpwere included to partially replace barley (Citrus 24% and Citrus 35%, respectively). Meat was aged under vacuum for 4 days and subsequently stored aerobically at 4 °C. The Control diet increased the redness, yellowness and satu...

  5. Proteomic Analysis of Human Tooth Pulp: Proteomics of Human Tooth

    Czech Academy of Sciences Publication Activity Database

    Eckhardt, Adam; Jágr, Michal; Pataridis, Statis; Mikšík, Ivan

    2014-01-01

    Roč. 40, č. 12 (2014), s. 1961-1966. ISSN 0099-2399 R&D Projects: GA ČR(CZ) GA13-17224S; GA ČR(CZ) GAP206/12/0453; GA MZd(CZ) NT14324 Institutional support: RVO:67985823 Keywords : dentin * human pulp * tandem mass spectrometry * tooth proteome * 2-dimensional gel electrophoresis Subject RIV: FF - HEENT, Dentistry Impact factor: 3.375, year: 2014

  6. Fluorapatite-modified Scaffold on Dental Pulp Stem Cell Mineralization

    OpenAIRE

    Guo, T.; Li, Y.; Cao, G.; Zhang, Z; Chang, S.; Czajka-Jakubowska, A.; Nör, J.E.; Clarkson, B.H.; Liu, J.

    2014-01-01

    In previous studies, fluorapatite (FA) crystal-coated surfaces have been shown to stimulate the differentiation and mineralization of human dental pulp stem cells (DPSCs) in two-dimensional cell culture. However, whether the FA surface can recapitulate these properties in three-dimensional culture is still unknown. This study examined the differences in behavior of human DPSCs cultured on electrospun polycaprolactone (PCL) NanoECM nanofibers with or without the FA crystals. Under near-physiol...

  7. Visibility of dental pulp spaces in dental ultrasound

    OpenAIRE

    Szopinski, K T; Regulski, P

    2013-01-01

    The purpose of this study was to assess the feasibility of dental ultrasound with conventional sonographic equipment. The teeth of three adult volunteers who had cone beam CT examinations performed previously with clinical indications and one extracted tooth were examined using linear and compact (hockey stick) sonographic probes. The sonographic images were compared with cone beam CT images reconstructed accordingly. Dental pulp spaces were demonstrated in all teeth not covered with prosthet...

  8. Histopathological Effect of Advanced Periodontal Disease on the Dental Pulp

    Directory of Open Access Journals (Sweden)

    Seyedmajidi M.

    2011-08-01

    Full Text Available Statement of Problem: Many authors have claimed that pulpal inflammation may occur following periodontal diseases. Appropriate diagnosis of different lesions that have affected the dental pulp or periodontium is critical for prevention of unnecessary or harmful treatments; this must be taken into account before treatment.Purpose: The purpose of this study was histological evaluation of the pulp in the teeth with advanced periodontitis.Materials and Method: 30 permanent single teeth root that had advanced periodontitis with attachment loss ≥ 5 mm at least in one surface were used. The teeth were not maintainable and did not have caries, restoration and any sign of primary trauma from occlusion and did not receive any periodontal professional treatment in the past 6 months with no background of trauma. After clinical and radiographical examination and confirmation of the existence of advanced periodontitis, the teeth were extracted. Then cracks were created in the teeth by special clips. After fixation of the teeth in 10% formalin solution and decalcification by 10% nitric acid, the sections were prepared and stained by hematoxylin and eosin and then evaluated from histological perspectives. The data were analyzed by Spearman correlation coefficient ANOVA, t-test and Kruskal wallis tests.Results: In this survey, we did not find any significant correlation between clinical findings and histopathological situation. The relationship between clinical attachment loss and pulp diagnosis was statistically significant ( p =0.043. Also there was a statistically significant relationship between clinical attachment loss and calcification in the pulp ( p =0.014.Conclusion: According to the result of this research, it seems that periodontal condition affects the pulpal condition and it should be considered in future treatments on these teeth.

  9. Dental pulp vascular permeability changes induced by dental bleaching

    OpenAIRE

    Cristiane da Costa; Sueli Patricia Harumi Miyagi; Marcelo dos Santos; Manoel Eduardo de Lima Machado; Márcia Martins Marques

    2012-01-01

    Aiming to compare the effect of different light sources for dental bleaching on vascular permeability of dental pulps, forty-eight incisors were used. The bleaching agent (35 % hydrogen peroxide) was activated by halogen light; LED (Light Emitting Diode) or LED, followed by laser phototherapy (LPT) (λ = 780 nm; 3 J/cm²). After the bleaching procedures, the animals received an intra-arterial dye injection and one hour later were sacrificed. The teeth were diaphanized and photographed. The...

  10. Ultrastructural characterization (morphological and topochemical) of wood pulp fibres

    OpenAIRE

    Fernando, Dinesh

    2007-01-01

    Different electron microscopy techniques including SEM (scanning electron microscopy), FE-SEM (field emission-scanning electron microscopy), TEM (transmission electron microscopy) and Immuno-gold TEM (immuno-gold transmission electron microscopy) were applied in order to gain a better understanding of the influence of the native softwood fibre cell wall ultrastructure including morphology and topochemistry (i.e. lignin and glucomannan distribution) during mechanical pulping. In thermomechanic...

  11. Use of coffee pulp as feed ingredient for tilapia culture

    OpenAIRE

    Ulloa Rojas, J.B.

    2002-01-01

    This research focused on the feasibility of using coffee pulp (CoP) in diets for tilapia ( Oreochromis aureus ). First, a literature survey analyzed the limitations of CoP as an animal foodstuff (several antinutritional factors: ANF's, and high fibre contents), different ways to upgrade the CoP nutritional value and the maximal inclusion level of CoP in diets for ruminants, monogastric animals and fish ( Chapter 1 ).Next, an inventory of agricultural activities in the country (Costa Rica) was...

  12. Prediction of wood species and pulp brightness from roundwood measurements

    OpenAIRE

    Nilsson, David

    2005-01-01

    This thesis presents a number of studies, where a multivariate approach was taken to construct models that predict wood species and thermo mechanical pulp brightness from roundwood of Norway spruce and Scots pine. The first and second studies produced multivariate prediction models for wood species from the bark of spruce and pine. These models can be used for wood species classification and would replace the manual log assessment that takes place today. Principal Component Analysis, PCA, and...

  13. Determination of Flavonoids in Pulp and Peel of Mandarin Fruits

    OpenAIRE

    Branka Levaj; Verica Dragović-uzelac; Danijela Bursać Kovačević; Nesrete Krasnići

    2009-01-01

    The aim of this study was to determine total flavonoids and individually flavanon glycosides as well as antioxidant capacity in pulp and peel of two mandarin groups, namely Satsuma (Citrus unshiu Marcovitch) cv. Saigon and Clementine (Citrus reticulate var. clementine) cv. Corsica SRA 63. Total flavonoids content was measured using colorimetric method, whereas HPLC-PDA detection was used for the analysis of individual flavanone glycosides (narirutin, naringin and hesperidin). In addition FRAP...

  14. Integration of pulp and paper technology with bioethanol production

    OpenAIRE

    Phillips, Richard B; Jameel, Hasan; Chang, Hou Min

    2013-01-01

    Background Despite decades of work and billions of dollars of investments in laboratory and pilot plant projects, commercial production of cellulosic ethanol is only now beginning to emerge. Because of: (1)high technical risk coupled with; (2) high capital investment cost relative to ethanol product value, investors have not been able to justify moving forward with large scale projects on woody biomass. Results Both issues have been addressed by targeting pulp and paper industry processes for...

  15. Apolar Annonaceous Acetogenins from the Fruit Pulp of Annona muricata

    OpenAIRE

    Pierre Champy; Djibril Fall; Alice Melot; Christophe Gleye

    2009-01-01

    A methylene chloride extract of the pulp of Annona muricata L. was fractionated in search for scarcely functionalized Annonaceous acetogenins (type E). Previously known C-35 and C-37 mono-epoxy unsaturated compounds, epomuricenins-A and -B (1+2) and epomusenins-A and -B (3+4), were obtained. Two new mono-epoxy saturated C-35 representatives, epomurinins-A and -B (5+6) were also isolated.

  16. Study of pulp microflora in patients with cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    M.A. Safarov

    2010-06-01

    Full Text Available 335 patients aged 20 to 60 years with various parodontitis inflammatory diseases have been selected for research. All patients have been divided into four groups of different age: with rheumatism - 96 persons, with heart ischemic illness - 82 persons, with arterial hypertension - 89 persons, with neurocirculatory dystonia - 68 persons. The presented results of supervision show diagnostic significant changes of pulp microflora with odontogenic infection in patients, suffering cardiovascular diseases

  17. Optimization of enzymatic hydrolysis of fibre sludge from pulp mill

    OpenAIRE

    Zinchenko, Ganna

    2012-01-01

    This thesis is a part of a project which aims at utilizing fibre sludge from pulp mill as a source of biofuel production. The study concentrates on optimizing one of the processing steps, enzymatic hydrolysis, in converting fibre sludge to bioalcohol. The aim of the thesis was to find optimum process parameters that enable maximum yield of glucose after performing the enzymatic hydrolysis. For this purpose, a series of experiments with changed process parameters was conducted. Also, enzym...

  18. "New age" pulp therapy: personal thoughts on a hot debate.

    Science.gov (United States)

    Waterhouse, Paula Jane

    2008-07-01

    This article outlines the counterpoint delivered in the debate "Is Formocresol Obsolete?" It addresses the opinion supporting the need to move away from formaldehyde-containing preparations in the dental care of children. It is suggested that such a move should be made not just because of concerns relating to the possible toxicity of formaldehyde but to reflect a more contemporary, biologic approach to pulp therapy in the primary dentition. PMID:18565372

  19. Dietary citrus pulp improves protein stability in lamb meat stored under aerobic conditions

    DEFF Research Database (Denmark)

    Gravador, Rufielyn Sungcaya; Jongberg, Sisse; Andersen, Mogens Larsen;

    2014-01-01

    The antioxidant effects of dried citrus pulp on proteins in lamb meat, when used as a replacement of concentrate in the feed, was studied using meat from 26 male Comisana lambs. The lambs of age 90. days had been grouped randomly to receive one of the three dietary treatments: (1) commercial...... concentrate with 60% barley (Control, n=8), (2) concentrate with 35% barley and 24% citrus pulp (Cp24, n=9), or (3) concentrate with 23% barley and 35% citrus pulp (Cp35, n=9). Slices from the longissimus thoracis et lomborum muscle were packed aerobically and stored for up to 6. days at 4°C in the dark. The...... citrus pulp groups, Cp24 and Cp35, significantly decreased protein radicals and carbonyls, and preserved more thiols within six days of storage compared to the Control group. The citrus pulp groups significantly slowed down the rate of protein oxidation, indicating that dietary citrus pulp reduced...

  20. Direct pulp capping in an immature incisor using a new bioactive material

    Directory of Open Access Journals (Sweden)

    Sham S Bhat

    2014-01-01

    Full Text Available Preservation of the pulp in a traumatized immature fractured incisor tooth is of prime importance in order to achieve apexogenesis, a natural apical closure. The main factor influencing this is pulpal protection by a bioactive material proving optimum marginal seal in preventing any microleakage. This case report presents an 8-year-old female diagnosed with Ellis Class 3 fracture of immature tooth 11 involving the mesial pulp horn. Under rubber dam isolation, a partial pulpotomy was performed and the pulp was sealed using a new bioactive material BIODENTINE to stimulate apexogenesis, dentine replacement and pulp protection. The fractured segment was reattached for optimum esthetics, which was a concern for the patient. The patient was followed-up for 1, 3, 6 and 12 months, which revealed continued apical closure and maintenance of pulp vitality. The patient remained asymptomatic. This case report provides evidence for the potential use of Biodentine as an effective pulp capping material in the future.

  1. Recycling cellulase towards industrial application of enzyme treatment on hardwood kraft-based dissolving pulp.

    Science.gov (United States)

    Wang, Qiang; Liu, Shanshan; Yang, Guihua; Chen, Jiachuan; Ji, Xingxiang; Ni, Yonghao

    2016-07-01

    Cost-effectiveness is vital for enzymatic treatment of dissolving pulp towards industrial application. The strategy of cellulase recycling with fresh cellulase addition was demonstrated in this work to activate the dissolving pulp, i.e. decreasing viscosity and increasing Fock reactivity. Results showed that 48.8-35.1% of cellulase activity can be recovered from the filtered liquor in five recycle rounds, which can be reused for enzymatic treatment of dissolving pulp. As a result, the recycling cellulase with addition fresh cellulase of 1mg/g led to the pulp of viscosity 470mL/g and Fock reactivity 80%, which is comparable with cellulase charge of 2mg/g. Other pulp properties such as alpha-cellulose, alkaline solubility and molecular weight distribution were also determined. Additionally, a zero-release of recycling cellulase treatment was proposed to integrate into the dissolving pulp production process. PMID:27099940

  2. ON THE BLACK LIQUOR AND RECYCLE COOKING OF AS-AQ STRAW PULP

    Institute of Scientific and Technical Information of China (English)

    Haiqiang Shi; Beihai He; Bingyue Liu

    2004-01-01

    Thick black liquor, thin black liquor and solid state sodium hydroxide are added to the liquor treated by sulfur dioxide, then the blended liquor is used to recycle cooking of straw pulp. The black liquor,separated liquor and pulp of every cycles are analyzed respectively. Result shows that the content of lignin and organism in recycle black liquor and separated liquor increases faster in the first three cycles and then continues to increase slowly till four or five times, after that it trends to a stable state. The main organism separated from waste liquor of AS-AQ treated by sulfur dioxide is alkali-lignin,above 50% of total lignin in black liquor. The yield of pulp made from recycle cooking is steady, the hardness of pulp has a great improvement with recycle cooking. The brightness of pulp reduces correspondingly before bleaching, and after bleaching the brightness of pulp is relatively high and steady at the same sodium hypo chlorite dosage.

  3. Enzymatic Hydrolysis of Hydrotropic Pulps at Different Substrate Loadings.

    Science.gov (United States)

    Denisova, Marina N; Makarova, Ekaterina I; Pavlov, Igor N; Budaeva, Vera V; Sakovich, Gennady V

    2016-03-01

    Enzymatic hydrolysis of cellulosic raw materials to produce nutrient broths for microbiological synthesis of ethanol and other valuable products is an important field of modern biotechnology. Biotechnological processing implies the selection of an effective pretreatment technique for raw materials. In this study, the hydrotropic treatment increased the reactivity of the obtained substrates toward enzymatic hydrolysis by 7.1 times for Miscanthus and by 7.3 times for oat hulls. The hydrotropic pulp from oat hulls was more reactive toward enzymatic hydrolysis compared to that from Miscanthus, despite that the substrates had similar compositions. As the initial substrate loadings were raised during enzymatic hydrolysis of the hydrotropic Miscanthus and oat hull pulps, the concentration of reducing sugars increased by 34 g/dm(3) and the yield of reducing sugars decreased by 31 %. The findings allow us to predict the efficiency of enzymatic hydrolysis of hydrotropic pulps from Miscanthus and oat hulls when scaling up the process by volume. PMID:26634840

  4. AFM investigation of kraft pulp ber swelling in controlled humidity

    International Nuclear Information System (INIS)

    Full text: Kraft pulp fibers are wood fibers from softwood, typically spruce and pine, which are the main constituent for so called kraft paper. Kraft paper is used mainly for packaging applications, where a high strength is required. In this work, the swelling behavior of spruce kraft pulp fibers is investigated by atomic force microscopy (AFM). To perform this task, the AFM was equipped with a fluid cell and a setup where the relative humidity inside the fluid cell can be controlled. The setup enables to select any humidity value between approximately 5% and 80% relative humidity. With this setup, a change in surface morphology of the scanned area could be observed. Furthermore, the evolution of the characteristic surface wrinkles of dried pulp fibers with increasing humidity was quantified in two different ways. One way is to measure the distance between the surface wrinkles, the other to determine their height. It could be shown that the distance between the wrinkles is increasing, whereas the height is decreasing. This means that the surface is becoming smoother when the ber is swelling, which is best observed on a completely wet fiber. (author)

  5. Non-wood pulp mill concepts. Environment and economics

    International Nuclear Information System (INIS)

    In China, over 40% of the pulp used in the paper industry is produced from cereal straws, grasses and other non-wood sources, whereas, in Western Countries, the contribution of non-wood sources is currently very small. The average plant size in China is about one tenth of that in Nordic countries. The small plant size is mainly a consequence of the economy of raw-material collection, transportation and storage. In 1998, 107 Nordic paper and board mills produced 25 million tons of products, while about 6000 Chinese mills produced 28 million tons. The investments required for environmental protection are disproportionately large for the very small Chinese mills. The demand for paper and board in China has increased rapidly and is expected to keep increasing in the future. The predicted annual growth rate exceeds 6%. It would be possible to double non-wood paper production within about twenty years, if an economical and environmentally sound solution could be developed. In this article, integrated fibre and energy concepts, aimed at improving the economy non-wood pulping, are proposed. A simple new non-wood pulping process, capable of being integrated with local energy production, is outlined and preliminary cost estimates are presented. (orig.)

  6. Acid hydrolysis and carbohydrates characterization of coffee pulp

    Energy Technology Data Exchange (ETDEWEB)

    Urbaneja, G. [Universidad de los Andes, Trujillo (Venezuela). Nucleo Universitario Rafael Rangel; Ferrer, J.; Paez, G. [Universidad del Zulia, Maracaibo (Venezuela). Facultad de Ingenieria; Arenas, L.; Colina, G. [Universidad del Zulia, Marcaibo (Venezuela). Facultad de Agronomia

    1996-09-01

    Hydrolysis of coffee pulp with diluted sulfuric acid was studied by keeping boiling temperature with reflux, a liquid to solid ratio of 10:1 and a particle size {<=} 1.00 mm. Coffee pulp was treated using several acid concentration (C) and retention times (t). The hydrolysates were analyzed for total sugars by phenol-sulfuric acid and HPLC (TSPA and TSHPLC), reducing sugar (RS) by DNS and individual sugars by HPLC. Data were analyzed by using the Statistical Analysis System (SAS). The average sugar yields were: TSHPLC between 12.87-20.31% and 14.02-19.01%; TSPA between 23.41-19.07% and 25.74-30.58%; RS between 10.24-19.07% and 9.66-17.80% for (C) y (t) respectively, expressed as wt% of dry coffee pulp. The general range of variations for individual sugars was: xylose from 0.08 to 3.23; arabinose from 0.23 to 11.26; fructose from 0.90 to 3.00 and glucose from 1.30 to 6.31, expressed in gl{sup -1}. The sucrose varied between 0.08 and 3.96 and maltose between 0.01 and 3.50, also expressed in gl{sup -1} of hydrolysate. The overall efficiency of hydrolysis was 64% for TSPA and 67% for RS. (Author)

  7. Pulp nerve fibers distribution of human carious teeth: An immunohistochemical study

    OpenAIRE

    Tetiana Haniastuti

    2010-01-01

    Background: Human dental pulp is richly innervated by trigeminal afferent axons that subserve nociceptive function. Accordingly, they respond to stimuli that induce injury to the pulp tissue. An injury to the nerve terminals and other tissue components in the pulp stimulate metabolic activation of the neurons in the trigeminal ganglion which result in morphological changes in the peripheral nerve terminals. Purpose: The aim of the study was to observe caries-related changes in the distributio...

  8. Effect of unbleached pulp kappa number on the kinetics of chlorine dioxide delignification

    OpenAIRE

    Simões, Rogério Manuel dos Santos; Barroca, Maria J. M. C.; Castro, José Almiro A. M.

    2010-01-01

    Chlorine dioxide delignification of different unbleached kraft pulps from Eucalyptus globulus, having Kappa numbers of 12 to 18, was studied in the temperature range of 285 K to 358 K. The effect of the unbleached pulp Kappa number on the initial fast phase of delignification was investigated with respect to the depletion factors for Kappa number and chlorine dioxide concentration, as proposed by Barroca et al. Furthermore, the behaviour of the floor lignin content of the pulp, or the floor K...

  9. Dental Pulp and Dentin Tissue Engineering and Regeneration – Advancement and Challenge

    OpenAIRE

    Huang, George T.-J.

    2011-01-01

    Hard tissue is difficult to repair especially dental structures. Tooth enamel is incapable of self-repairing whereas dentin and cememtum can regenerate with limited capacity. Enamel and dentin are commonly under the attack by caries. Extensive forms of caries destroy enamel and dentin and can lead to dental pulp infection. Entire pulp amputation followed by the pulp space disinfection and filled with an artificial rubber-like material is employed to treat the infection --commonly known as roo...

  10. Induction of Reparative Dentin Formation on Exposed Dental Pulp by Dentin Phosphophoryn/Collagen Composite

    OpenAIRE

    Toshiyuki Koike; Mohammad Ali Akbor Polan; Masanobu Izumikawa; Takashi Saito

    2014-01-01

    The ultimate goal of vital pulp therapy is to regenerate rapidly dentin possessing an excellent quality using a biocompatible, bioactive agent. Dentin phosphophoryn (DPP), the most abundant noncollagenous polyanionic protein in dentin, cross-linked to atelocollagen fibrils was applied to direct pulp capping in rats. After 1, 2, and 3 weeks, the teeth applied were examined on the induction of reparative dentin formation and the response of pulp tissue, compared to calcium hydroxide-based agent...

  11. Distinctive genetic activity pattern of the human dental pulp between deciduous and permanent teeth.

    Directory of Open Access Journals (Sweden)

    Ji-Hee Kim

    Full Text Available Human deciduous and permanent teeth exhibit different developmental processes, morphologies, histological characteristics and life cycles. In addition, their pulp tissues react differently to external stimuli, such as the pulp sensitivity test, dental trauma and pulp therapy materials. These suggest differences in gene expression and regulation, and in this study we compared gene-expression profiles of the human dental pulp from deciduous and permanent teeth. Pulp tissues from permanent premolars and deciduous molars aged 11-14 years were extirpated and mRNA was isolated for cDNA microarray analysis, and quantitative real-time PCR (qPCR. Other teeth were used for immunohistochemical analysis (IHC. Microarray analysis identified 263 genes with a twofold or greater difference in expression level between the two types of pulp tissue, 43 and 220 of which were more abundant in deciduous and permanent pulp tissues, respectively. qPCR analysis was conducted for eight randomly selected genes, and the findings were consistent with the cDNA microarray results. IHC confirmed that insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1 was broadly expressed in deciduous dental pulp tissue, but minimally expressed in permanent dental pulp tissue. Immunohistochemical analysis showed that calbindin 1 (CALB1, leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5, and gamma-aminobutyric acid A receptor beta 1 (GABRB1 were abundantly expressed in permanent predentin/odontoblasts, but only minimally expressed in deciduous dental pulp tissue. These results show that deciduous and permanent pulp tissues have different characteristics and gene expression, suggesting that they may have different functions and responses to therapies focused on pulp or dentin regeneration.

  12. Pembuatan Dan Karakterisasi Bata Konstruksi Dengan Memanfaatkan Limbah Padat Pulp Dan Semen

    OpenAIRE

    Siti Aisyah Ritonga

    2009-01-01

    Penelitian ini dilakukan dengan tujuan pemanfaatan limbah padat pulp dregs, grits, dan biosludge dalam pembuatan bata. Pada penelitian ini digunakan limbah padat pulp dregs, grits, dan biosludge, dengan variasi komposisi semen 0%, 5%, 10%, 15%, 20%, 25%, dan 30%. Proses pencetakan benda uji dilakukan dengan cara cetak tekan sebesar 5000 kg force. Hasil penelitian menunjukkan bahwa kuat tekan bata dengan campuran limbah padat pulp pada komposisi semen 30% menyamai kuat tekan bata normal. Hasil...

  13. POTENTIAL OF FINES AS REINFORCING FIBRES IN ALKALINE PEROXIDE PULP OF OIL PALM EMPTY FRUIT BUNCH

    OpenAIRE

    Nurul H. Kamaludin,; Arniza Ghazali,; Wan Daud Wanrosli

    2012-01-01

    Pulp from the alkaline peroxide mechanical pulping (APMP) of oil palm empty fruit bunch, EFB, was fractionated with varying mesh-size screens to examine the effects imposed by size-specific fines on the produced pulp network. Occurring mainly as a result of refining, fines elements with dimensions almost resembling EFB fibres were the long tube-like tapered vessels from the arrays of adjoined cell walls detached along the perforation lines. These fibrillated vessel elements constituting the P...

  14. On the behaviour of lignin rich pulps upon irradiation with light. Pt. 1

    International Nuclear Information System (INIS)

    The work deals with investigations on changes taking place in brightness, lignin content and methoxyl content upon irradiation of differently prepared unbleached and semi-bleached pulps from beech and spruce with light of more or less the same the spectral distribution as daylight. The results show that the change in brightness depends to a large extent on the used pulping method as well as on the pulping conditions. Pulps prepared according to the alkaline sulphite method as well as according to the soda method display an increase in brightness upon exposure to light. The behaviour of pulps produced by the neutral-sulphite-semichemical method (NSSC-Method) depends mainly upon the pulping conditions. Pulps produced under relatively mild conditions regarding alkalinity and cooking temperature show a great decrease in brightness by irradiation. Pulping at relatively high alkalinity and temperature leads to pulps, which show at first a slight increase in brightness, after which practically no change in colour occurs. Bisulphite pulps decrease in brightness under the same conditions. In all cases there was a significant decrease in the lignin content due to light irradiation. The lignin content of NSSC-pulps from beech wood decreases at a higher rate than the lignin content of pulps prepared by the alkaline sulphite method. The loss in the methoxyl content was in all cases higher than that of lignin. The amount of water-soluble extractives increases by lengthening the exposure time, the pH-value of the extractives decreases in the same direction. The characteristic maximum at 280 nm decreases in intensity to a large extent after irradiation. (orig.)

  15. Evaluation of antibacterial effects of pulp capping agents with direct contact test method

    OpenAIRE

    Yalcin, Muhammet; Arslan, Ugur; Dundar, Ayse

    2014-01-01

    Objectives: Calcium hydroxide has been used in dentistry as a major capping material having the capacity to introduce the formation of a mineralized dentin bridge, but it has no direct inducing effect to the pulp cells. The purpose of this study was to evaluate the antibacterial properties of three different pulp capping agents using a direct contact test (DCT). Materials and Methods: The antibacterial properties of three pulp capping agents were evaluated a DCT. For the DCT, wells (n = 12) o...

  16. Scaffoldless Tissue-engineered Dental Pulp Cell Constructs for Endodontic Therapy

    OpenAIRE

    Syed-Picard, F.N.; Ray, H.L.; Kumta, P.N.; Sfeir, C.

    2014-01-01

    A major cause of apical periodontitis after endodontic treatment is the bacterial infiltration which could have been challenged by the presence of a vital pulp. In this study, self-assembled, scaffoldless, three-dimensional (3D) tissues were engineered from dental pulp cells (DPCs) and assessed as a device for pulp regeneration. These engineered tissues were placed into the canal space of human tooth root segments that were capped on one end with calcium phosphate cement, and the entire syste...

  17. Indirect pulp therapy in a symptomatic mature molar using calcium enriched mixture cement

    OpenAIRE

    Hassan Torabzadeh; Saeed Asgary

    2013-01-01

    Dental pulp has the ability of repair/regeneration. Indirect pulp therapy (IPT) is recommended for pulp preservation in asymptomatic teeth with extremely deep caries as well as teeth with clinical symptoms of reversible pulpitis. In this case study, we performed IPT with calcium enriched mixture (CEM) cement on a symptomatic permanent molar. After clinical/radiographic examinations the tooth was diagnosed with irreversible pulpitis and associated apical periodontitis. IPT involved partial car...

  18. Microbial and enzymatic control of pitch in the pulp and paper industry

    OpenAIRE

    Gutiérrez Suárez, Ana; Río Andrade, José Carlos del; Martínez Ferrer, Ángel Tomás

    2009-01-01

    Pitch control is an important aspect in pulp and paper manufacture, and the first example where microbial biotechnology provided successful solutions in this industrial sector. Triglycerides cause deposits in softwood mechanical pulping, and both microbial and enzymatic products have been commercialized to be applied on wood and pulp, respectively. The former are based on colorless strains of sapstain fungi. The latter are improved lipases, including thermostable variants from directed evolut...

  19. Direct Dental Pulp Tissue Grafting – a Novel Approach to Regenerative Endodontics

    OpenAIRE

    Liang, Zhangrui

    2015-01-01

    The translation of dental pulp stem cells (DPSC) transplantation into clinic practice is hindered by the Good Manufacturing Practice (GMP) approval for in vitro autologous DPSC expansion. In order to circumvent the laboratory procedure, we proposed an unprecedented approach for regenerative endodontics – direct dental pulp tissue grafting. This study has demonstrated that cells directly migrating out from dental pulp tissue explantation (DPTE), functioning as the putative cell source in our a...

  20. Transcriptomic Analysis Reveals Key Genes Related to Betalain Biosynthesis in Pulp Coloration of Hylocereus polyrhizus

    OpenAIRE

    Qingzhu, Hua; Chengjie, Chen; Zhe, Chen; Pengkun, Chen; Yuewen, Ma; Jingyu, Wu; Jian, Zheng; Guibing, Hu; Jietang, Zhao; Yonghua, Qin

    2016-01-01

    Betalains have high nutritional value and bioactivities. Red pulp pitaya (Hylocereus polyrhizus) is the only fruit containing abundant betalains for consumer. However, no information is available about genes involved in betalain biosynthesis in H. polyrhizus. Herein, two cDNA libraries of pitaya pulps with two different coloration stages (white and red pulp stages) of Guanhuahong (H. polyrhizus) were constructed. A total of about 12 Gb raw RNA-Seq data was generated and was de novo assembled ...