Pulp and paper
Seyed_Pedram Hashemi; Asghar Tabei; Seyyed Peyman Hashemi
Abstract
In this study the effect of different values of peroxide in three levels 3%, 4%, 5% and sodium hydroxide in two levels 2%, 3%, on bleaching of tobacco stalks ( Nicotiana tabacum L. 'PVH 19') soda pulp was investigated. Tobacco stalks were soda pulped using 22% alkali in 170°C for 100 minutes. Produced ...
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In this study the effect of different values of peroxide in three levels 3%, 4%, 5% and sodium hydroxide in two levels 2%, 3%, on bleaching of tobacco stalks ( Nicotiana tabacum L. 'PVH 19') soda pulp was investigated. Tobacco stalks were soda pulped using 22% alkali in 170°C for 100 minutes. Produced pulp had 37.1 % yield and kappa number 62. Bleaching process included two stages: chelating and alkali peroxide bleaching. Results indicated that brightness increased and kappa number decreased by increasing sodium hydroxide and peroxide Hydrogen level.The data related to 3% caustic soda and 5% peroxide treatment without chelating stage, indicated that initial chelating stage significantly affected on the brightness, kappa number and yield of the bleached pulp, and this treatment had the lowest brightness and the highest kappa number and yield among all treatments. Finally, 3% caustic soda-5% peroxide treatment with initial chelating stage had the highest brightness (44.50%) and the lowest yield (83.20%), was selected as the best treatment.
Physics and anatomy
ahmad saraiyan; soodeh zhand
Abstract
In this study, the effect of boiling water pre-treatment on yield, optical, physical and mechanical properties of NSSC (Neutral Sulfite Semi Chemical) pulp from Zagroos wheat straw (Golestan province) was investigated. Chopped wheat straw was pretreated in boiling water for 30 minutes, water to straw ...
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In this study, the effect of boiling water pre-treatment on yield, optical, physical and mechanical properties of NSSC (Neutral Sulfite Semi Chemical) pulp from Zagroos wheat straw (Golestan province) was investigated. Chopped wheat straw was pretreated in boiling water for 30 minutes, water to straw ratio of 10:1. NSSC pulping was carried out at constant pulping conditions including liquor to straw ratio of 10:1, maximum pulping temperature of 160ºC and 30 minutes pulping time. In order to study the effect of NaOH on strength properties of paper, in some trails only Na2S03 were used. Pulping was followed by defibration in laboratory refiner to reach 380±25mlCSF freeness. Handsheets at 60gr/m² were made from each pulp. The strength properties were determined on the basis of TAPPI standard. Results show that pre-treatment imparted a significant increasing effect on the strength properties of papers such as tensile, burst, breaking length, stiffness and density, except RCT strength. Increasing the chemical charge specially NaOH improved the pulp freeness, yield and handsheet density but the handsheet thickness was reduced.
Pulp and paper
Hossein Jalali trshizy; Saeideh Zarea bidkei; Omid Rmazani; Hamidreza Rodi
Abstract
Bio and synthetic polymers; micro and recently nano particles have been applied in wet end section of papermaking industry. Very special attention is focused toward their advantages for controlling the process variables and improving the product quality made from recycled ...
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Bio and synthetic polymers; micro and recently nano particles have been applied in wet end section of papermaking industry. Very special attention is focused toward their advantages for controlling the process variables and improving the product quality made from recycled papers. In the presence of cationic starch polymer as an anionic trash reducer in the pulp slurry, the effects of cationic polyacrylamide (CPAM)-bentonite nanoparticle complex on retention, drainage and paper properties made from old corrugated container (OCC) was evaluated. The results showed that addition of CPAM polymer individually enhanced burst, tensile and tear strength indices. The application of nano bentonite following CPAM has significantly increased all of mentioned pulp and paper properties. Dewatering rate analysis by Dynamic Drainage Jar and laboratory handsheet maker revealed that the time for the paper manufacturing can be reduced. Moreover, raw material to final product ratio (total retention) increased from 96.7% up to 98.7%. Long chain cationic polyacrylamide shows high capability as the flocculation of papermaking ingredients, individually and particularly in combination with nano bentonite, especially for fines which is a high portion in the recycled pulps. Thus the problem resulting from not retaining sufficient ingredients and the pollution load of the paper mill effluent will be reduced.
Pulp and paper
farzaneh shiralizadeh; mohammad azadfallah; ali Abdolkhani; mohammad Layeghi; saeed mahdavi
Abstract
This study was conducted with the aim of producing laboratory samples of transparent paper using overbeating method. Hence, bagasse bleached soda pulp was subjected to post-bleaching sequence of DED to remove residual chromophores. Then this pulp was refined in a PFI mill to reach different ...
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This study was conducted with the aim of producing laboratory samples of transparent paper using overbeating method. Hence, bagasse bleached soda pulp was subjected to post-bleaching sequence of DED to remove residual chromophores. Then this pulp was refined in a PFI mill to reach different levels of 55, 130, 200, and 260 mL,CSF (Canadian standard freeness) freeness. Then handsheets were made according to TAPPI standard T 205 om– 8. Results indicated that refining has significant effect on optical properties especially transparency so that the maximum value was observed using pulp with the minimum freeness, i.e. 55 ml. The variations of transparency due to refining were also further explained by measuring scattering coefficient, opacity and brightness of the specimens. In addition, mercury porosimetry and analyzing the pictures of scanning electron microscopy (SEM) demonstrated the extensive variations of pore structure in paper during refining which impose great influence on developing transparency.
Pulp and paper
Nazbakht Hezbi; Elyas Afra; Hossein Resalty
Abstract
In this research, the effect of different steps of enzymatic treatment including enzymatic pre-refining and post-refining by Endoglucanase was investigated on the quality of OCC pulp. Three pulps including a: control sample (without enzyme addition), b: enzymatic pre-refining (enzyme treatment + refining) ...
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In this research, the effect of different steps of enzymatic treatment including enzymatic pre-refining and post-refining by Endoglucanase was investigated on the quality of OCC pulp. Three pulps including a: control sample (without enzyme addition), b: enzymatic pre-refining (enzyme treatment + refining) and c: pre and post enzymatic refining (enzyme + refining + enzyme) were made from OCC pulps. Enzymatic treatment was done at optimum conditions before determined (concentration of 1u and time duration of 0.5 hour) under constant process conditions and refining accomplished at given revolution of 2000. Obtained results from this research indicated that applying enzymatic pre-treatment had efficient in improving the physical and mechanical of paper and showed the highest strength than to the other treatments. Using Endoglucanase at two stages (before and after refining) caused to improve pulp drainability and decrease the paper strength properties. In general, the maximum tear index was observed in enzymatic pre-refining step.
Pulp and paper
Lila Karami motaghi; Hossein Hosseinkhani; Fardad Golbabaei
Abstract
In this study pulp and hand sheets paper characteristics of Salix nigra wood kraft and soda pulp and paper were investigated. Average density of dry and bulk density wood were determined 0.35 and 150 kg/m3 and average fiber dimension consist of fiber length, fiber diameter were measured, 1100 and 30 ...
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In this study pulp and hand sheets paper characteristics of Salix nigra wood kraft and soda pulp and paper were investigated. Average density of dry and bulk density wood were determined 0.35 and 150 kg/m3 and average fiber dimension consist of fiber length, fiber diameter were measured, 1100 and 30 µm, respectively. The chemical composition were determined as cellulose 42%, lignin 28% and extractive 4%. In order to coocking and pulping, Kraft (Sulfate) and soda process were used. For comparison of fiber dimensions, physical properties and chemical composition of the mean and standard deviation, yields of pulp in the form of a factorial randomized complete block design test, the strength properties of handsheets table ANOVA and for group means of the Duncan were used. All paper strengths of two hour cooking show better results than one hour cooking times, and all paper strengths of 22% alkaline show better result than 18%, also all paper strengths of 100% mixture show better result than 25% mixture (100% mixture only contain kraft pulpof salix nigra). The results of hand sheet strength indicated that Kraft pulp of salix nigra wood will provide a suitable to mix with short fiber hard wood pulp.
Chemistry of wood
Seyyed Peyman Hashemi Beygzadmahalleh; Seyyed Pedram Hashemi Beygzadmahalleh; Asghar Tabei
Abstract
Tobacco (Nicotianan tabacum) and an old industrial plant in the north, Iran to supply tobacco leaf to produce significant amounts of stem tobacco cultivation and the annual production is in the north of the country. In this research stems of tobacco variety Coker 347 randomly Gilan district, city of ...
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Tobacco (Nicotianan tabacum) and an old industrial plant in the north, Iran to supply tobacco leaf to produce significant amounts of stem tobacco cultivation and the annual production is in the north of the country. In this research stems of tobacco variety Coker 347 randomly Gilan district, city of Astara was prepared according to the TAPPI standard test, wood flour were prepared and extractives were determined. The results showed that the mean shoot extractive tobacco varieties Coker 347 (10.41 percent). The extractive solvent toluene - ethanol volume ratio (2 : 1) of milled wood was extracted. Extractive made into a glass vial and transferred to the BSTFA reagent was added. Samples for one hour at room temperature and 70 ° C water bath and then by (GC / MS) were analyzed. Atotal of 11 chemical compounds in tobacco stem wood extractives variety Coker 347 were identified with different percentages of tobacco stem wood Coker 347 varieties exist. These compounds include, P- Prydyn , 1 – tri methyl Saylyl , 1,2 - benzene di- carboxyl acid , alpha - D - Golokopyranoz , 11, 8 – di methyl - 13 - (4 - aksu -1 - methyl ) , tri Floyver methyl isopropyl sulfide are the highest values.
Pulp and paper
Hadi Hasanjanzadeh; sahab hejazi; saeed mahdavi
Abstract
In this study, rice straw as an abundant and cheap raw material selected to produce soda - anthraquinone pulp. Nano fiber Cellulose of rice straw were added to improve the pulp strength after cationing. Cationed suspension was mixed at three levels including 2, 5 and 10 percent with nano fiber cellulose. ...
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In this study, rice straw as an abundant and cheap raw material selected to produce soda - anthraquinone pulp. Nano fiber Cellulose of rice straw were added to improve the pulp strength after cationing. Cationed suspension was mixed at three levels including 2, 5 and 10 percent with nano fiber cellulose. Starch and polyacrylamide as cationic chemicals were used to stabilize nano fiber cellulose at 1.5% and 0.2% based on oven dried pulp, respectively. The result showed that there is linear change between stock drainage time and paper strength according to nano fiber cellulose added content. Tensile and burst index were improved at 18.66% and 18.12% respectively by adding 10% of nano fiber cellulose to suspension treated with cationic polyacrylamide. Furthermore, the two indices increased until 19.35% and 19.24% by adding of maximum amount of nano fiber cellulose (10%) to cationed pulp suspension with cationic starch, respectively. The use of nano fiber cellulose had a positive significant effect on paper properties.
Pulp and paper
Ahmad Samariha; Jafar Ebrahimpoor kasmani; Saeed Mahdavi
Abstract
Rapeseed straw was collected from a cultivation farm in the vicinity of Babul, Mazandaran. Average fiber length, width, lumen diameter and cell wall thickness were measured as 860, 27.95, 18.86, and 4.42 µm respectively. Chemical components of rapeseed straw including cellulose, lignin, ash and ...
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Rapeseed straw was collected from a cultivation farm in the vicinity of Babul, Mazandaran. Average fiber length, width, lumen diameter and cell wall thickness were measured as 860, 27.95, 18.86, and 4.42 µm respectively. Chemical components of rapeseed straw including cellulose, lignin, ash and extractives were measured as 44%, 19.21%, 6%, and 13% respectively. Optimum pulping conditions to reach the pulp yield of 66%, were selected applying chemical charge of 20% (based on Na2O), cooking temperature of 170 ºC, and cooking time of 30 min. The pulps were refined to 350 and 400 ml CSF using PFI mill. Statistical analysis showed that mechanical properties of hand sheets with the basis weight of 127 g m-2 made from rapeseed straw NSSC pulp at the freeness of 350 and 400 ml CSF exhibited better properties compared to mixed hardwood NSSC pulp to produce fluting paper.
Pulp and paper
Saeideh Sharifi; Ahmad reza Saraeyan; Hossein Resalati
Abstract
Preparation and pre-treatment of raw material influences the pulp production time and color elimination. Pulp consistency during the treatment also influences the color reaction. In the preparation of the APMP pulp, bagasse was pretreated by either boiling water, 1% NaOH as well as 1% NaOH + 1% ...
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Preparation and pre-treatment of raw material influences the pulp production time and color elimination. Pulp consistency during the treatment also influences the color reaction. In the preparation of the APMP pulp, bagasse was pretreated by either boiling water, 1% NaOH as well as 1% NaOH + 1% H2O2. The liquor to bagasse ratio, treatment time and temperature of alkaline peroxide treatment were constant as 10:1, 30 min, and 70 °C respectively. The treatment duration was determined so that at least five percent of the initial hydrogen peroxide remained at the end of chemical treatment. Characteristics of hand sheets were determined according to the TAPPI standard. The results showed that, the duration of the treatment for pulp consistency of 10, 15 and 20% was 50, 30 and 10 minute, for sample pretreated with boiling water and 290, 230 and 170 minute for the sample pretreated with 1% NaOH + 1% H2O2. The highest brightness of the paper reached with bagasse pretreated in boiling water at 20 % consistency.
Pulp and paper
Amir hooman Hamasi; Mehdi Sabor; Mohammad Talaeipoor; Mohammad Azadfallah
Abstract
The aim of present study was to investigate the effects of xylanase enzyme obtained from Trichoderma viride on APMP pulp from Populus nigra wood. Treatment temperature, time, enzyme dosage and pulp consistency were varied. The results demonstrated that treating by xylanase has considerable effects on ...
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The aim of present study was to investigate the effects of xylanase enzyme obtained from Trichoderma viride on APMP pulp from Populus nigra wood. Treatment temperature, time, enzyme dosage and pulp consistency were varied. The results demonstrated that treating by xylanase has considerable effects on pulp. Paper brightness improved in average 2.5% ISO and the highest gain was 4.5%. Also, using enzyme resulted in enhancement of tear and burst indices. Breaking length of paper from enzyme treated pulp was increased to 4098 meters. Further treatment by xylanase reduced the pulp yield by 2.78% as compared to sample without enzyme treatment. The impact of other treatment such as washing by distilled water and alkaline extraction revealed that these treatments did not have significantly effect on the results of enzyme treatment. The optimum temperature, time, enzyme dosage and pulp consistency were 40-50° C, 70 minutes, 10 U/g of oven dried pulp and 10% respectively.
Chemistry of wood
Amir mohsen Nazry; Mohammad Talaeipoor; Saeed Mahdavi
Abstract
The effects of different fines with different shape and size of mechanical Pulp on Paper Properties in two fractions was investigated. Fines was classified in two categories including fibrils and flakes , and then effect of these particles on pulp properties was studied.The fibril fraction was consist ...
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The effects of different fines with different shape and size of mechanical Pulp on Paper Properties in two fractions was investigated. Fines was classified in two categories including fibrils and flakes , and then effect of these particles on pulp properties was studied.The fibril fraction was consist of fibrillar material, i.e., ribbons, fibrils, and thin lamella particles. The flake fraction consist of flake like material i.e., fiber wall fragments and thick lamella. An advanced image analysis method was used to characterize the properties of fibrils and flakes. The results indicate that the fibrils and flake fractions have distinct characteristics and effect on sheet properties. The fibrils strongly affected the strength properties, while the flakes improved light scattering. Generally, the smaller size Particles afforded higher sheet density and strength. Fines content and fibrillar material are very important parameters in mechanical pulping and can also affect quality controlling of mechanical pulp and papermaking.
Pulp and paper
Maryam Rostaei; Rabi Behroz; Saeid Mahdavi
Abstract
This research was performed to improve the properties of the pulp made of Aspen Deltoides, using antraquinone(AQ) catalizer. Neutral sulfite semichemical (NSSC) method in three efficiency levels of 55, 60, and 65% was applied. Cooking situations was selected as: Specific Temperature (175˚ C) , Time ...
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This research was performed to improve the properties of the pulp made of Aspen Deltoides, using antraquinone(AQ) catalizer. Neutral sulfite semichemical (NSSC) method in three efficiency levels of 55, 60, and 65% was applied. Cooking situations was selected as: Specific Temperature (175˚ C) , Time (Variable) , Specific Percentage of Chemicals 14% and Anthraquinone 0.1% . In all stages of cooking, weight ratio of sodium sulfide to sodium bicarbonate was set as 4.5/1. The ratio of cooking liquid to chips was 5/1. The results indicated that AQ causes an increase in efficiency and a significant decrease in Kappa. Researches also indicated that by the use of AQ, strength indexes of the paper such as strength of burst, tearing, tensile, Ring Crush Test and Corrugating Medium Test increases. Optical experiments on hand sheets following addition of AQ, indicated increase in brightness and decrease in opacity.
Pulp and paper
Ahmad Jahan latibari
Abstract
In an attempt to develop pulping process suitable for small scale implementation, production of bleachable chemi-mechanical pulp from wheat starw is investigated. Four levels (10, 12, 14 and 16% based on oven dry weight of straw) NaOH and three pulping times (20, 30 and 40 minutes) at 95°C pulping ...
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In an attempt to develop pulping process suitable for small scale implementation, production of bleachable chemi-mechanical pulp from wheat starw is investigated. Four levels (10, 12, 14 and 16% based on oven dry weight of straw) NaOH and three pulping times (20, 30 and 40 minutes) at 95°C pulping temperature were used. After digester yield varied between 64.65 and 71.7% and the total yield after defibration was measured as 54.45% and 62%. Unrefined pulp freeness varied between 708 and 765 ml CSF. Pulps produced applying 10-16% NaOH, 40 minutes pulping time and 95°C pulping temperature was selected from further evaluation. These pulps were refined to about 365 ml CSF in a PFI mill and then handsheets were made for strength evaluation. The apparent density of the handsheets varied between 437-488 kg/m3, tear index between 6.51-7.11 mN.m2/g, and tensile index between 29.2 -30.8 N.m/g. Significant difference at 99% was not observed between the strength of the pulps. Then pulp produced applying 10% NaOH, 40 minutes pulping time and 95°C pulping temperature was selected for bleaching trials. Totally Chlorine Free (TCF) bleaching sequence was used for bleaching the selected pulp. Pulps bleached applying 4% H2O2 and 3.5% NaOH, 3% sodium Silicate, 0.5% MgSO4 and 0.3% DTPA for 2 hours showed the highest brightness of 50.69% compared to 29.2% for unbleached pulp.
Pulp and paper
Somayeh Solimani; Sayed javad Sepidehdam; Hamid Malkian
Abstract
The stability of colored paper through dyes is very important in manuscript restoration. In this project Japanese papers (model papers) were colored with different dyes such as henna, walnut and tea. Artificial aging test was performed on these papers as well. Dye effect on stability of colored papers ...
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The stability of colored paper through dyes is very important in manuscript restoration. In this project Japanese papers (model papers) were colored with different dyes such as henna, walnut and tea. Artificial aging test was performed on these papers as well. Dye effect on stability of colored papers was measured through mechanical (folding endurance, tensile breaking and tear resistance) tests before/after aging test statistically; folding endurance test results in color level is significant. Tea colored paper sample was not as stable as model paper in folding resistance and the average of tea sample compare to model sample was 39.9 to 69.5. Folding endurance reduction was seen in tea and henna samples following aging test. The effects on tensile and tear resistance were not statistically different or dyes were not affected to cause any increase or decrease in stabilities. Scanning electron microscopy (SEM) images of model and dyed papers have demonstrated color and aging effects. The pH test upon henna sample, have shown acidic condition. Model paper was not the same as dyed papers in terms of weight and thickness. All samples include model and dyed papers, demonstrated decrease in brightness and yellowness and increase in redness following aging test.
Pulp and paper
Hamd Unesi kord khalili; Mehran Jalilvand; Rabi Behroz
Abstract
The purpose of this study was to investigate effects of different loading levels and addition of urea formaldehyde and polyethylene on the creep behavior of composites made from wastes of OCC recycling mills. The composites manufactured by hot press method and three-point ...
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The purpose of this study was to investigate effects of different loading levels and addition of urea formaldehyde and polyethylene on the creep behavior of composites made from wastes of OCC recycling mills. The composites manufactured by hot press method and three-point bending test performed before creep test. In general, the results showed positive effects of additive materials such as urea formaldehyde and polyethylene on the creep behavior of the composites. While adding UF and PE decreased primary and final creep as well as return deformation percentage of the composites. Also the obtained results indicated that remaining creep had higher sensitivity to loading levels compared to primary and final creep. Also the increase of the load levels from 20% to 30% led to an increase in creep content of the composites.
Pulp and paper
Ahmad Samariha; Jafar Ebrahim poor tasmani; Alireza Khakifiroz
Abstract
This research was performed to investigate the properties of CMP pulp from rape straw. Samples of Colza straw was prepared from a farm located in the vicinity of Babul. Chemo mechanical Pulping process was employed using the 20 % cooking liquor of Mazandaran pulp and paper mill (Sodium Sulphite) based ...
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This research was performed to investigate the properties of CMP pulp from rape straw. Samples of Colza straw was prepared from a farm located in the vicinity of Babul. Chemo mechanical Pulping process was employed using the 20 % cooking liquor of Mazandaran pulp and paper mill (Sodium Sulphite) based on the dry weight of colza straw. Cooking time and temperature were adjusted at 30, 40 and 50 minute and 170 degree centigrade, respectively. Pulps were refined up to 300± 25 CSF by using PFI Mill refiner and 60 g/m2 hand sheets were made from each sample of pulps. The strength indices of hand sheets were measured using TAPPI standards. The results showed that strength indices like Tensile strength, Tear strength, Burst strength, Breaking length and Stiffness increased as the pulp yield decreased.
Pulp and paper
Mohammad taghi Asdolah zadeh; Hossein Resalti; Ali Ghasemian
Abstract
In the present study the effects of hot water pre-extraction and alkaline catalyzed were evaluated on soda-aq pulping of kenaf whole stem. In this respect, following kenaf chips pre-extraction at various temperature and time conditions, pulp preparation were carried out on oven-dried weight loss levels ...
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In the present study the effects of hot water pre-extraction and alkaline catalyzed were evaluated on soda-aq pulping of kenaf whole stem. In this respect, following kenaf chips pre-extraction at various temperature and time conditions, pulp preparation were carried out on oven-dried weight loss levels of 8.5, 11.5 and 14.5 % of the samples, and the reference untreated kenaf chips performed by using Soda-AQ at 3 levels of H-factors ( 983, 1408 and 1832 hours). Results indicated that kenaf chips weight losses increased while the pre-extracted pH decreased as pre-extraction temperature and time increased. The required H-factor for achieving certain level of weight loss was reduced by adding small amounts of alkali (0.15 % on oven dried kenaf) on hot water extraction stage. The Pulp yields were reduced by increasing cooking H-factor and extracted weight loss. Averages comparison indicated that significant differences were observed, at 95% confidence, between the pulp yield and kappa number from reference pulp and pre-extracted pulp samples at levels of about 8.5, 11.5 and 14.5 %, and pulp yields and their kappa number were higher in reference pulps than pre-extracted samples. In addition, pulp yield average was higher in pre-extracted samples by alkaline catalyzed than pre-extracted samples by hot water, however, no significant differences were observed between their kappa number average. Meanwhile, to obtain a certain (similar) kappa number, pre-extracted kenaf chips in comparison with reference untreated kenaf chips require lower H-factor.
Pulp and paper
Rabi Behroz; Hamed Unsi kord khelili; Saeid Kazemi najafi
Abstract
Effect of Kraft lignin as a compatibilizer on the short-term water absorption (2 and 24 hours) and mechanical properties of wood flour-polypropylene composites was studied. The black liquor of Chooka pulp and paper mill was acidified and Kraft lignin was extracted by precipitation. The extracted ...
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Effect of Kraft lignin as a compatibilizer on the short-term water absorption (2 and 24 hours) and mechanical properties of wood flour-polypropylene composites was studied. The black liquor of Chooka pulp and paper mill was acidified and Kraft lignin was extracted by precipitation. The extracted lignin at three levels of 2, 5 and 10 percent was mixed with wood flour by physical mixing method. All materials used were oven-dried. Wood flour, lignin and PP with or without MAPP were used to produce composites by flat hot press method. The results of this study indicated that generally lignin improved physical (short term water absorption) and mechanical properties (flexural modulus, flexural strength and impact strength). The bending test result showed that without MAPP, the composites with 2 and 10 percent lignin exhibited higher flexural modulus and strength, respectively. But at the presence of compatibilizer, the composites with 5 percent lignin exhibited the highest flexural modulus and strength. The composite with 2 percent of lignin exhibited higher flexural modulus and short-term water absorption rather than the composites with 2% MAPP. This result indicated positive effect of lignin in the composites. Also the composites with 10 percent lignin exhibited the highest impact strength and short-term water absorption. But there were no significant difference between the impact strength of composites with 5 and 10 percent lignin.
Pulp and paper
Babak Mirzaei; Kazem Dos hosseini; Esmaeil Ghasemi; Yahya Hamzeh
Abstract
In this study two types of paper sludge, prepared by Mazandaran wood and paper company and Latif papermaking company along with wood flour utilized as plastic filler in polypropylene and high density polyethylene based composites. Weight percentage ratio of coupling agent, polymer and filler were kept ...
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In this study two types of paper sludge, prepared by Mazandaran wood and paper company and Latif papermaking company along with wood flour utilized as plastic filler in polypropylene and high density polyethylene based composites. Weight percentage ratio of coupling agent, polymer and filler were kept constant 2%, 38%, and 60% in all formulations, respectively and composites were prepared by varied ratios of paper sludge and wood flour include 0: 60, 40: 20, 20: 40, and 60:0. Density, water absorption and thickness swelling of injection molded composites then measured. The results indicated the gradual substitution of wood flour by paper sludge increases the density of composites, and improves their water absorption and thickness swelling. The ratio of paper sludge to wood flour had statistically significant difference on all these properties, but the paper sludge type showed statistical difference just on the density of composites. Further to that, polypropylene based composites demonstrated lower density, water absorption and thickness swelling compared to high density polyethylene based ones.
Pulp and paper
Ali Solimani; Hossein Resalati; Eiman Akbarpoor
Abstract
In this research, effects of mixing the birch wood with hornbeam and beach on optical and physical properties of papers produced at constant freeness range of 300 ml, CSF and yield of 85% and reference of CMP pulp (75% hornbeam plus to 25% beach) was investigated. CMP pulp was produced from birch ...
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In this research, effects of mixing the birch wood with hornbeam and beach on optical and physical properties of papers produced at constant freeness range of 300 ml, CSF and yield of 85% and reference of CMP pulp (75% hornbeam plus to 25% beach) was investigated. CMP pulp was produced from birch chips at 10,20,30 and 40% content within the conditions of pulp yield:85%, liquor to dried chip ratio (L/W) of 7/1, sulfite percent of 20% on oven-dried wood chips, cooking temperature:1600C, cooking time:85-135 minutes blended with 60-90 % hornbeam and beach. After defibration and refining the cooked wood chips, the standard hand sheets of 60 g/m2 were made from different pulps and the optical and physical properties of paper produced were compared. The results from comparing the optical properties of paper showed that using up to 40% birch chips blended with hornbeam and beach led to brightness improvement and yellowness and opacity reduction compared to control CMP pulp. Increase of birch use to 30% indicated no significant effect on opacity values at confidence level of 99% compared to control CMP pulp. Utilizing 40% birch resulted in the preparation of papers with lower caliper, smoother surface and higher air resistance.
Pulp and paper
Davod Efhami; Mohammad reza Dehghani
Abstract
In this work effect of initial alkali charge were investigated on the yield and kappa number of soda beech pulp and alkali consumption pattern. The results indicated that, the regression models are useful for studying the relations between yield, kappa number and alkali consumption. Soda cooking was ...
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In this work effect of initial alkali charge were investigated on the yield and kappa number of soda beech pulp and alkali consumption pattern. The results indicated that, the regression models are useful for studying the relations between yield, kappa number and alkali consumption. Soda cooking was performed in 30, 40, 50, 60 and 70 gr.lit-1 initial alkali concentration and five different cooking times. The chips dimensions were in the range of 3-5 cm length, 1-2 cm width and 0.05 cm thickness. The results showed that increasing of alkali charge decreased the time of cooking in the same yield or kappa number. Deligninifaction decreased significantly in kappa number lower than 30. In the same kappa number, increased alkali charge gave a lower yield. The alkali consumption was regularly decreased with increasing of initial alkali charge from 30 to 70 gr/lit, but alkali charge consumption pattern varied in less and more than 30 kappa numbers.
Chemistry of wood
Mohammad ali Azad far; Rabie Behroz; Ahmad Jahan - Latibari
Abstract
The influence of oxygen delignification as an environmental friendly process, was investigated on Soda/AQ pulp from Old Corrugated Container (OCC) fibers. Oxygen delignification at four levels of alkali (2, 3, 4 and 6% based on OD weight of pulp) has been applied and the optimum alkalinity to reach optimum ...
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The influence of oxygen delignification as an environmental friendly process, was investigated on Soda/AQ pulp from Old Corrugated Container (OCC) fibers. Oxygen delignification at four levels of alkali (2, 3, 4 and 6% based on OD weight of pulp) has been applied and the optimum alkalinity to reach optimum Kappa no, yield and brightness, opacity and strength based on 60 g/m2 hand sheets were determined. The results indicated that application of oxygen delignification marginally reduced the opacity of the pulp. Tear strength increased where as tensile and burst strength decreased. Based on the comparison of the data from oxygen delignified pulp, it is concluded that oxygen can be utilized to improve the properties of soda-AQ pulp from OCC prepared for bleaching step. Carbohydrates are preserved while removing lignin. Normalized equations revealed that oxygen delignification at 3% alkali produced the best results.
Pulp and paper
Yahya Hamzeh; Babak Mirzaei; Kazem Dost hosseini; Alireza Ashori; Kambiz Rashedi; Alyeh olfat
Abstract
Characteristics of pulp and paper mill solid wastes depend generally on the raw materials, stock preparation process as well as wastewater treatment plant. In order to determine the best application of paper mill solid wastes, physicochemical properties of solid waste produced in the Mazandaran Wood ...
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Characteristics of pulp and paper mill solid wastes depend generally on the raw materials, stock preparation process as well as wastewater treatment plant. In order to determine the best application of paper mill solid wastes, physicochemical properties of solid waste produced in the Mazandaran Wood and Paper Industry Co. and Latif Paper Co. were analyzed. The dry content, pH, fiber dimensions, composition of organic and inorganic compounds of the both solid were analyzed. The dry content of the produced wastes in Latif and Mazandran were determined as 69.3 and 36.7 percent, respectively. The pH of both wastes was close to neutral (pH/7.0). The fiber length of Latif and Mazandaran wastes were 1.68 and 1.08 mm, respectively. In addition, the total amount of carbohydrates, glucose and mannose quantity in the Latif waste were determined as 48.09, 29.5 and 7.2 percent that were higher than that of Mazandaran waste. In the contrary, the lignin, xylose and galactose content of Mazandaran waste were determined as 15.3, 17.3 and 3.7 percent that were higher than those of Latif waste. The mineral content of Latif and Mazandarn wastes were determined 44.7 and 39.5 percent, respectively. XRF analyses revealed that the predominant elements in the incinerated ash of both wastes contained calcium oxide, aluminum oxide and silicon oxidethat can be used as raw material for lightweight concrete and zeolite synthesis.
Pulp and paper
Reza Hosseinpoor; Ahmad Jahan - Latibari; Ajang Tajdini; Sayed javad Sapideh dam; Ramin Farnod
Abstract
The impact of chemical treatment variables including treatment time and temperature, chemical charge as well as pulp freeness on fiber quality of Colza stem chemi-mechanical pulp was studied using Fiber Quality Analyzer (FQA). Three treatment times (15, 30 and 45 minutes), two treatment temperatures ...
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The impact of chemical treatment variables including treatment time and temperature, chemical charge as well as pulp freeness on fiber quality of Colza stem chemi-mechanical pulp was studied using Fiber Quality Analyzer (FQA). Three treatment times (15, 30 and 45 minutes), two treatment temperatures (125 and 145 °C), two chemical charges (4% NaOH + 8% Na2SO3 and 8% NaOH +12% Na2SO3) as well as pulp refining were evaluated. The results revealed that at higher values of treatment variables, fiber average length was reduced and varied between 0.49 and 0.65 mm. However, the influence of pulp refining on fiber average length was not very pronounced. Pulps contained between 55 -63 % fines, which is on the high range and refining increased the fine content by 5%. Fiber coarseness varied between 10 and 41 mg/100m which was raised to 14 and 53 mg/100m upon refining. Even though refining did not alter fiber curl, but fiber kinks were increased.