Raw Material For Pulp Production Research Articles

Simultaneous Adsorption of Cu2+ and Cd2+ by a Simple Synthesis of Environmentally Friendly Bamboo Pulp Aerogels: Adsorption Properties and Mechanisms.

The highly efficient, pollution-free and degradable biomass-based adsorbents used for the purification of wastewater are currently being highlighted in the research. Bamboo is an excellent raw material for pulp production due to its characteristics of fast growth, wide distribution and high cellulose content. In this study, a tannin/chitosan/bamboo pulp aerogel (TCPA), an environmentally friendly, renewable and low-density adsorbent, was synthesized using a simple freeze-drying method and analyzed by FTIR, XPS, SEM, TEM, TGA and surface area and porosity methods. TCPA has a large specific surface area (137.33 m2/g) and 3D porous structure, and its surface has multiple functional groups including amino, carboxyl and hydroxyl groups, which lead to a simultaneous absorption effect with Me2+ (Cu2+ and Cd2+). The maximum adsorption capacity for Cu2+ and Cd2+ of the TCPA was 72.73 mg/g and 52.52 mg/g, respectively. The adsorption processes of Me2+ by TCPA follow the pseudo-second-order model and Langmuir isotherm mode, and the adsorption processes are spontaneous and endothermic. The study provides a promising candidate for the treatment of wastewater containing heavy metal mixtures.

FEATURES OF THE PRIMARY PREPARATION OF HEMP STRAW STALKS SUITABLE FOR OBTAINING CELLULOSECONTAINING MATERIALS AND PAPER

The features of the primary preparation of hemp straw stalks suitable for obtaining cellulosecontaining materials and paper are considered in the article. The primary processes of the preparation of hemp raw materials for pulp production, which include harvesting, storage of straw stalks, transportation, and primary processing of raw materials suitable for obtaining cellulose-containing materials, are described. Methods of shortening stems and fibers applied in the pulping process are studied in detail. Technological methods of shortening straw stalks of technical hemp and cleaning raw materials from grains and garbage impurities are mentioned. The necessity of applying the processes of stalks crushing and wet purification of chopped straw stalks of technical hemp is proved.

Pulp Production and Optimization from Cotton Stalks

Currently there is no pulp producing factory in Ethiopia. This is because pulp production is highly energy and water intensive, acquiring the raw material (wood cultivation and preparation) is costly and time taking. The study initiated by these problems and aimed at optimizing pulping variables and selecting suitable delignification conditions for the production of pulp from cotton stalk. The influence of operational variables on the pulp yield and lignin dissolution of cotton stalks was studied. Cotton stalks chips were delignified in a laboratory pulp wood according to the Kraft pulping process. The conditions used were: active alkali charge (5- 25%), sulfidity (10-50%), cooking temperature (155-175 oC and cooking time (30 – 150 minutes). The cotton stalks chip size and liquor to solid ratio was kept constant at 2 cm X 0.5 cm X 0.5 cm on average and 5 L to 1 kg, respectively. Experimental data were fitted into a central composite design and a quadratic equation has developed. Model prediction for pulp yield and kappa number showed good agreement with experimental data with error values less than 5%. Optimum pulp percent yield (39.6%) was obtained using at 15% of active alkali, 20% of sulfidity, 165 oC temperature and 30 minutes of cooking time. The study showed that pulping at low temperatures for a short cooking time with high concentration of pulping liquor gives the best compromise for both pulp yield and kappa number/residual lignin content. The result of morphology analysis showed that cotton stalks has similar fiber dimensions with eucalyptus. From the results of the study it is recommended that cotton stalk, which is by product of cotton production, can be used as a raw material for pulp production.

Variation of chemical characteristics and pulpability of dhaincha (Sesbania bispinosa) on location

Dhaincha ( Sesbania bispinosa ) is a crop generally cultivated for improving soil quality. Due to the lack of forest worldwide, alternative source of raw materials for cellulose industries is the main concern today. In this investigation dhaincha samples were collected from 21 accessions of different districts of the country in order to study variation of chemical characteristics and its pulpability. The lignin, pentosan and α –cellulose content were varied from 21 to 23%, from 16 to 18% and from 38 to 43%, respectively. The highest and lowest α –cellulose content were found in two location of Mymensngh district. There was no correlation was found among the district. Therefore, pulping of dhaincha from selected seven districts was carried out in kraft process at the conditions of 18% active alkali at 170 o C for 2 h. But the pulping properties did not show any mentionable distinction for place variation. Average pulp yield is 42.9% with kappa number 11. The highest brightness 85% ISO was reached with D 0 E p D 1 bleaching. The papermaking properties were very close to the conventional raw materials used in Bangladesh. Therefore, dhaincha can be used as a raw material for pulp production in Bangladesh.

Anaerobic digestion of wastewater from the production of bleached chemical thermo‐mechanical pulp – higher methane production for hardwood than softwood

ABSTRACTBACKGROUNDChemical thermo‐mechanical pulp (CTMP) mills holds a large biomethane potential in their wastewater. Their broadened market has involved increased bleaching and utilization of different raw materials. Therefore, the main aim of this study was to obtain and maintain a well‐functioning anaerobic digestion (AD) process, with a high methane yield and total organic carbon (TOC) reduction, when digesting CTMP wastewater, from different production protocols including shifts in raw material and bleaching. A lab‐scale upflow anaerobic sludge bed (UASB) reactor was used for the tests.RESULTSThe variations in raw material (spruce, birch and aspen) and consequently in TOC‐loading (3.6–6.6 kg TOC m−3 and day−1) did not affect the UASB process negatively. Methane production values from 360 to 500 NmL g−1 TOC were obtained, with the highest yield for wastewater from the production of birch‐ followed by aspen‐ and spruce pulp. The acetic acid and filtered‐TOC (fTOC) reduction ranged from 90 to 95% and 61 to 73%, respectively.CONCLUSIONSA well‐functioning process maintained during shifts in raw material for pulp production which shows that AD is feasible for CTMP mills with a diversified product portfolio. Furthermore, the increased use of hardwood and bleaching will most likely increase their potential as a biomethane producer. © 2016 Society of Chemical Industry

Stellera chamaejasme Roots as Raw Material for Pulp Production

Cellulosic pulps were prepared from Stellera chamaejasme roots using soda, soda-anthraquinone (soda-AQ), and kraft pulping processes. S. chamaejasme is composed of 73.5% holocellulose, 39.7% α-cellulose, and 17.6% lignin, similar to wheat straw and other non-wood plant materials. The ethanol–benzene extractives content of 9.2% is higher than other non-woods. The conditions used for all pulping experiments were as follows: a liquid/solid ratio of 5:1; a time-to-maximum temperature of 100 min; a maximum temperature of 160 °C; and a time-at-maximum temperature of 50 min. The results showed that the pulp yield was 31.27 to 36.83%, the kappa number was 16.32 to 19.42, and the pulps’ intrinsic viscosity was 854 to 976 mL/g. Tear index, tensile index, burst index, and brightness of the papers made from the above unbleached pulps were 12.60 to 13.62 mN•m2/g, 20.57 to 22.56 mN/g, 2.16 to 2.38 kPa•m2/g, and 15.3 to 18.3%, respectively.

Characterization of Cypress Wood for Kraft Pulp Production

Wood samples of Cupressus arizonica, C. lusitanica, and C. sempervirens were evaluated for chemical, anatomical, and pulp characteristics as raw material for pulp production. Two 17-year-old trees per species were harvested, and wood samples were taken at a height of 2 m. Wood chips from Pinus pinaster (Portugal) and P. sylvestris (Finland) were used as references. C. arizonica differed from C. lusitanica and C. sempervirens with significantly lower (p < 0.05) tracheid diameter and wall thickness in the earlywood. The total extractives contents were 3.9%, 3.3%, and 2.5% for C. lusitanica, C. sempervirens, and C. arizonica, respectively, lower than the 5.1% for P. pinaster and 4.5% for P. sylvestris. Klason lignin content ranged from 33.0 to 35.6%, higher than the 28.0 to 28.7% for the pinewoods. The kraft pulp yields for C. arizonica, C. lusitanica, and C. sempervirens were 37.7%, 36.7%, and 38.7%, respectively, with kappa numbers of 32.0, 31.6, and 28.7, respectively; the yield values were 40.8% and 42.8%, with kappa numbers of 23.4 and 21.0, for P. pinaster and P. sylvestris, respectively. The cypress species are clearly different from pine in relation to wood pulping behavior. Among the cypress, C. sempervirens provided the best pulping results.

Effect of pre-hydrolysis on the soda-anthraquinone pulping of corn stalks and Saccharum spontaneum (kash)

► Pre-extraction removed pith from the corn stalks and kash. ► Dissolved materials in the pre-extracted liquor can be used for biomaterials and fuels. ► Pre-extracted pulp showed almost similar strength properties. ► Pre-extracted pulp showed almost similar bleachability. The limited reserves of fossil fuel and trend of global warming increase interest in renewable resources. In this circumstance, significance has been developed on the production of fuels and chemicals from biomass that will replace fossil fuel. Corn stalks and Saccharum spontaneum (kash) are agricultural wastes, which are good raw materials for pulp production. However, there are limitations in achieving the desired pulp quality due to the presence of pith. The pith constitutes 20–35% of the dry matter of the raw materials. It must be removed prior to pulping to obtain good quality pulp. Chemically pith is similar to lignocellulosic, but it does not have fibrous structure. So the pith can be used in producing fuels and chemicals. Pre-hydrolysis prior to soda-AQ pulping of corn stalks and kash was carried out in order to remove pith as well as to extract hemicelluloses for use as fuel and chemicals. The pre-hydrolysis was performed at 150 °C for 1 h. Pre-hydrolysis extracted 50–60 kg sugars, 28–34 kg lignin and 8–22 kg acetic acid per tonne of corn stalks/kash with the sacrifice of pulp yield. Pre-hydrolysed pulp had less fines resulting in lower drainage resistance ( 0 SR) as compared to non-prehydrolysed counterpart. Pulp produced from the pre-hydrolysed corn stalks and kash had higher tear index but lower tensile index than the non-prehydrolysed counterpart. The pre-hydrolysis process requires careful optimization of the pulping process, and allows lower chemical charges. After D 0 E p D 1 bleaching, the differences of pulp yield and physical properties were reduced. The pre-hydrolysed pulp showed almost similar bleachability to non pre-hydrolysed pulp.

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

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.

Semichemical pulping of Miscanthus giganteus. Effect of pulping conditions on some pulp and paper properties

Miscanthus is an interesting raw material for pulp production, it is a high yield low maintenance plant with a high cellulose and hemicellulose content. Its semichemical pulp can be beneficial in paper for cardboard production process, which nowadays is usually made from secondary fibers, by increasing the mechanical properties of the paper produced. In this study, the influence of the percentage of NaOH used related to the dry Miscanthus weight, digestion time and refining time on some pulp and paper properties have been studied and compared with pulp obtained from commercial fluting paper (CF). Fiber size distribution of the Miscanthus pulp was found to contain a higher fines (less than 0.2 mm) percentage than the CF pulp. Hand-sheets made from Miscanthus pulp showed better mechanical properties than the ones made with the CF pulp. CMT, RCT and CCT indexes were higher when using 100% Miscanthus pulp or mixtures of Miscanthus and CF pulp. The only property which worsened was Gurley porosity. Of the three operational variables changed, refining time exerts the most significant influence on the pulp and paper properties measured.

Substituting Wood with Nonwood Fibers in Papermaking: A Win-Win Solution for Bangladesh

Bangladesh is facing an acute shortage of fibrous raw materials for the production of pulp and paper. On the other hand, the demand for paper and paper products is increasing day by day. This study reviews the availability and suitability of nonwood raw materials for pulp production in Bangladesh. It shows that Bangladesh has a huge amount of unused jute fiber, which is highly suitable for papermaking in Bangladesh. Other agricultural wastes like rice straw, dhaincha, golpata fronds, cotton stalks, corn stalks, and kash are also available and may be used for some pulp production. Given the different properties of these different nonwood fibers, jute pulp can be used as a reinforcing agent with other nonwood pulps for the production of high quality paper in Bangladesh.

Willow wood (Salix alba) as a raw material for pulp production

The properties of willow wood (structural-physical and mechanical properties and chemical composition) were investigated to determine the parameters of the technological process of semichemical and sulphate pulp manufacture. The experimental material was willow wood Salix alba cl. 107/65/7. Semichemical and sulphate pulp were obtained in the laboratory. The yield, chemical properties and physical-mechanical properties of the obtained intermediate products intended for paper manufacture, were determined. The properties of poplar wood Populus deltoides Bartr. cl.725, were studied and its pulp production performed with the aim of comparison.

An economic analysis of the financial viability of switchgrass as a raw material for pulp production in eastern Ontario

This paper examines the economic viability of producing switchgrass ( Panicum virgatum) to be used as pulp in fine paper production. Pulp mills in eastern Ontario and western Quebec are considered to be the potential market for switchgrass. The potential size of the market for switchgrass pulp is assessed. Budgets for switchgrass are constructed and various measures of the potential market value of switchgrass are calculated. Based on these preliminary findings, it appears that switchgrass could be an attractive crop for farmers in eastern Ontario and western Quebec. The total land area required to satisfy the potential demand for switchgrass fibre for pulping in eastern Ontario is estimated to be between 22,000 and 48,000 hectares. Further agronomic research to examine the productivity of switchgrass on economically marginal and erosion prone lands is indicated.

96/05175 Experimental performance of the water/calcium chloride system in a heat transformer

The limited reserves of fossil fuel and trend of global warming increase interest in renewable resources. In this circumstance, significance has been developed on the production of fuels and chemicals from biomass that will replace fossil fuel. Corn stalks and Saccharum spontaneum (kash) are agricultural wastes, which are good raw materials for pulp production. However, there are limitations in achieving the desired pulp quality due to the presence of pith. The pith constitutes 20–35% of the dry matter of the raw materials. It must be removed prior to pulping to obtain good quality pulp. Chemically pith is similar to lignocellulosic, but it does not have fibrous structure. So the pith can be used in producing fuels and chemicals.Pre-hydrolysis prior to soda-AQ pulping of corn stalks and kash was carried out in order to remove pith as well as to extract hemicelluloses for use as fuel and chemicals. The pre-hydrolysis was performed at 150 °C for 1 h. Pre-hydrolysis extracted 50–60 kg sugars, 28–34 kg lignin and 8–22 kg acetic acid per tonne of corn stalks/kash with the sacrifice of pulp yield. Pre-hydrolysed pulp had less fines resulting in lower drainage resistance (0SR) as compared to non-prehydrolysed counterpart. Pulp produced from the pre-hydrolysed corn stalks and kash had higher tear index but lower tensile index than the non-prehydrolysed counterpart. The pre-hydrolysis process requires careful optimization of the pulping process, and allows lower chemical charges. After D0EpD1 bleaching, the differences of pulp yield and physical properties were reduced. The pre-hydrolysed pulp showed almost similar bleachability to non pre-hydrolysed pulp.