Pulp and paper
Abas Fakhryan; Fardad Golbabaei; Mohammad mehdi Brazandeh
Abstract
In this research pulp and paper making characteristics of Sequoia sempervirens from Chamestan noor research station were studied. The dry and critical specific gravity of sap wood 0.352 and 0.324, heart wood 0.43 and 0.40, fiber length 2.01 mm. diameter 39.84µm. lumen 33.15µm and cell thickness ...
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In this research pulp and paper making characteristics of Sequoia sempervirens from Chamestan noor research station were studied. The dry and critical specific gravity of sap wood 0.352 and 0.324, heart wood 0.43 and 0.40, fiber length 2.01 mm. diameter 39.84µm. lumen 33.15µm and cell thickness wall 2.89µm were measured as respectively. The amount of cellulose of 52.63%, lignin 35.32%, ext. 6.68% and ash 0.45% were obtained as well. Kraft process was used for pulping. The yield of these pulps in 12% effective alkali were measured as 56% and in 18% effective alkali 39.69% respectively. In 3 hours of cooking time, the tear strength of these pulps 19.74 mNm2/gr and In 2 hours of cooking time 15.22 mNm2/gr respectively were measured.
Chemistry of wood
Iman Akbarpour; Hossein Resalati
Abstract
This research was accomplished in order to investigate the replacement of organic complex of Glanapone Stab with sodium silicate on optical properties of hardwood CMP pulp bleached by hydrogen peroxide. The highest brightness of 65.5% and the lowest yellowness of 21.6% was attained at silicate-free ...
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This research was accomplished in order to investigate the replacement of organic complex of Glanapone Stab with sodium silicate on optical properties of hardwood CMP pulp bleached by hydrogen peroxide. The highest brightness of 65.5% and the lowest yellowness of 21.6% was attained at silicate-free followed by replacement of 0.7% and 1.5% Glanapone. But the highest opacity 98.2% was gained using 0.5% glanapone. The brightness of paper increased to 68.1% and the yellowness decreased to 20.8. by adding of glanapone consumption from 0.4% to 0.5% in blended with 0.7% sodium silicate. At higher levels than 0.5% glanapone, the brightness of paper decreased and the yellowness increased. Using Higher levels of 1 and 1.5% glanapone in blended with 0.7% sodium silicate resulted the highest opacity 97.9% and 98%, respectively. Increasing of peroxide usage up to 5% at two different states of silicate-free and silicate-containing with glanapone resulted in the paper with higher brightness and lower yellowness and opacity. CMP pulps bleached at 120 minutes resulted the highest brightness of 71.1% and the lowest yellowness of 18.3% at silicate-containing state with glanapone. Maximum opacity of 98.3% and 98% were shown at bleaching time 30 minutes at two states silicate-free and silicate-containing state with glanapone, respectively. In this research with regard to optical properties in relation to paper produced from CMP pulp bleaching at two states silicate-free and silicate-containing with glanapone,it can be said that possibility of producing the paper with similar optical properties or even better using 0.7% or 1.5% at silicate-free is in compared to conventional hydrogen peroxide bleaching. Also, we could produce the paper with higher brightness along with lower yellowness and similar opacity followed by bleaching time of 120 minutes and hydrogen peroxide 5% in combination of 0.7% sodium silicate with 0.5% glanapone in compared to higher consumed values of sodium silicate.
Pulp and paper
Saeid Kamrani; Ahmad reza Saraeyan; Eyman Akbarpoor
Abstract
In this study, mechanical and optical properties of CMP, one stage APMP and two stage APMP pulps ( from Tajan wheat straw Golestan province ) were investigated. wheat straw collected at research center of Agriculture and Natural resources of Golestan province. Fiber dimensions such as average fiber length ...
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In this study, mechanical and optical properties of CMP, one stage APMP and two stage APMP pulps ( from Tajan wheat straw Golestan province ) were investigated. wheat straw collected at research center of Agriculture and Natural resources of Golestan province. Fiber dimensions such as average fiber length , diameter cell , lumen and fiber wall thickness were assessed at 1.18mm, 18.156, 11.461 and 3.396 microns, respectively. chemical components such as cellulose , lignin , ash and extractives were assessed at 53.7, 21.1, 5.1 and 8.5 percent, respectively. Based on the preliminary experiment results, impregnation temperature was 950C, impregnation times of 10, 20, 30, 40 minutes, caustic charge 10% and peroxide charge was 3% in CMP ,one stage APMP and two stages APMP pulps. Considering pulp properties and treatment conditions, many treatments including 20 and 40 minutes treatments were selected for making of handsheet. The selected pulps were refined up to 350 ml (CSF) freeness prior to making of hasndsheet. Final results indicated that two stages APMP pulp (impregnation in time 40 minutes) had the highest burst strength, breaking length and brightness. Also, the results of yield and tear strength showed that, there was no meaningful difference at the 5% level between three methods CMP, one and two stages of APMP pulps.
Pulp and paper
Pyvand Darabi; Hamideh Abdolzadeh; Ali naghi Karimi; Seeyed Ahmad Mirshokraie; Kazem Doosthoseini
Abstract
In this study capability of acetylated poplar flour in manufacture of high density poly ethylene composite which expose to accelerated weathering, was investigated. The acetylation degrees at medium and zero (control) levels, use of anti- oxidant and duration of weathering were considered as variables ...
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In this study capability of acetylated poplar flour in manufacture of high density poly ethylene composite which expose to accelerated weathering, was investigated. The acetylation degrees at medium and zero (control) levels, use of anti- oxidant and duration of weathering were considered as variables and their effects on discoloration and photodegradation of WPC were investigated. To determine treatments influence on changes and color fade resulting from weathering, samples were tested after o, 250, 2000 hours of weathering. The results indicated that application of acetylated wood flour in WPC can reduce about 25% of weathering discoloration in short time and about 17% in long time. Also it shows that as exposed time of weathering increase Anti oxidant loss its effect. Although in short time it can reduce 12% of weathering color changes. FTIR results show that after 2000 h of weathering all peaks samples had same decrease which mean none of the treatments were useful. But Anti oxidant can reduce depth of weathering.
Pulp and paper
Mohammad Molaei; Aliakbar Enayati; Yahya Hamzeh; Maryam Rostaei
Abstract
A fundamental study was carried out to explore the canola stalks properties in order to increase the use of abundant agricultural residuals in pulp and paper production. In this study, the morphological, chemical composition and soda pulping properties of Canola stalks were investigated. The results ...
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A fundamental study was carried out to explore the canola stalks properties in order to increase the use of abundant agricultural residuals in pulp and paper production. In this study, the morphological, chemical composition and soda pulping properties of Canola stalks were investigated. The results showed that except the thicker cell wall, the morphological properties of Canola stalks fibers were comparable to those of nonwoods and hardwoods fibers. Chemical analysis indicated that Canola stalks contains lower amount of cellulose (44%), while the lignin, hemicelluloses and ash content of Canola stalks are comparable to other non-woods. In comparison with most of non wood fiber resources, soda pulping of Canola stalks required higher chemical charge and pulping time. Soda pulping of Canola stalks in 22% active alkaline and 100 min in max temperature produced pulp with 82.6% ISO of brightness The strength properties of bleached Canola stalks soda pulp include tensile index (Nm/g), burst index (kpam2/g) & tear index (mNm2/g) showed respectively 63.6, 2.22 & 4.9.
Pulp and paper
Mohammad Ahmadi; Mohammad mehdi Faezipoor; Ahmad Jahan latibari; Sahab Hejazi
Abstract
Neutral sulfite semi chemical pulping of Canola residues has been investigated. Canola residues collected from research farm at Agriculture and Natural Resources, University of Tehran, in Karaj. Chemical composition of Canola residues including cellulose, lignin, extractives soluble in ethanol-acetone ...
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Neutral sulfite semi chemical pulping of Canola residues has been investigated. Canola residues collected from research farm at Agriculture and Natural Resources, University of Tehran, in Karaj. Chemical composition of Canola residues including cellulose, lignin, extractives soluble in ethanol-acetone and ash were determined using relevant TAPPI standard test methods. Fiber dimensions of Canola residues were also measured. Then neutral sulfite semi chemical pulps were produced from Canola residues applying following conditions: Cooking time at 3 levels(20,40,60min),chemical charge at 5 levels(8,10,12,14,16 %), Cooking temperature was kept constant for all cooks at 175ċ , Na2SO3 to Na2CO3 ratio was 3:1,and liquor to Canola residues at 8:1. Each pulping was repeated tree times. At the end of each cooking, initial defibration was carried out using a laboratory disc refiner. Total yield before defibration and yield after defibration and screened yield were determined. The highest yield (72%) was obtained at treatment combination of and the lowest yield (58.7%) was in treatment of .Both factors, time and chemical charge, had significant effect on yield and increasing these two factors caused lower yield.
Pulp and paper
Somayeh Ghasemi; Ahmad reza Saraeyan
Abstract
Comparative study of pulp yield of sap wood and heart wood of Populus deltoides under both Kraft and soda cooking process have been showed that the heart wood pulp has a lower yield than that of sap wood pulp. Yield of heart wood and sap wood soda pulps was 4 percentages higher than Kraft pulp. Contrary ...
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Comparative study of pulp yield of sap wood and heart wood of Populus deltoides under both Kraft and soda cooking process have been showed that the heart wood pulp has a lower yield than that of sap wood pulp. Yield of heart wood and sap wood soda pulps was 4 percentages higher than Kraft pulp. Contrary to yield, residual lignin content (Kappa number) is more in heart wood pulp than sap wood pulp in both processes. Kappa numbers of heart wood and sap wood Kraft pulps were about 34% lower than soda pulps. The results showed that in spite of lower yield of heart wood than sap wood, the residual lignin of heart wood pulp was more than sap wood pulp. The higher delignification efficiency of Kraft cooking is related to cooking liquor compositions, especially Na2S
Pulp and paper
Abbas Fakhryan roghani; Fardad Golbabaei; Hossein Hosseinkhani; Kamyar Salehi; Saeed Mahdavi; Sabrineh Mohsseni tavakoli
Abstract
In this reseach, chemical, anatomical and pulping properties of 12 years old Populus.triplo of adapting plan and quantity properties of this tree from karaj research station were investigated.The average of fiber length ,diameter ,lumen and thickness of cell wall 1.27 mm ,31.88 um, 23.54 um and 4.22 ...
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In this reseach, chemical, anatomical and pulping properties of 12 years old Populus.triplo of adapting plan and quantity properties of this tree from karaj research station were investigated.The average of fiber length ,diameter ,lumen and thickness of cell wall 1.27 mm ,31.88 um, 23.54 um and 4.22 um and cellulose ,lignin , Ext. and ash %53.74 , %22.87 , %1.8 and %1.5 were measured respectively.The yield and kappa number of pulps between 41.152% - 48% and 18.06 – 25.28 were measured.In 14% and 18% effective alcoholli, tearh index 9.307 mNm²/gr and 10.147 mNm²/gr were obtained.
Pulp and paper
Mohammad Azadfallah; Arezo Noori
Abstract
Yellowing of lignin-rich mechanical pulp is mainly attributed to light-induced changes in lignin structure. Hence, in this study the photodegradation of milled wood lignin (MWL) prepared from hardwood bleached chemimechanical pulp (BCMP) was investigated. The lignin preparation was then impregnated on ...
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Yellowing of lignin-rich mechanical pulp is mainly attributed to light-induced changes in lignin structure. Hence, in this study the photodegradation of milled wood lignin (MWL) prepared from hardwood bleached chemimechanical pulp (BCMP) was investigated. The lignin preparation was then impregnated on Whatman filter paper and irradiated with UV light during 4 hour exposure time. Then, photodegraded lignin was recovered and characterized by 13C-NMR.Irradiation caused to β-O-4 bonds cleavage, increase in carboxylic and phenolic hydroxyl groups, decrease in methoxyl, primary and secondary hydroxyl group. The amount of β-β and β-5 condensation structures was increased during irradiation.
Pulp and paper
Ali Khalili gasht rodkhani; Ali Ghasemian; Ahmad reza Saraeyan; Mohammad Dahmardeh ghale no; Sayed mehdi Manzorolajdad
Abstract
This study was aimed to investigate the effects of mixing OCC fibers with mixed hardwoods kraft pulp at Iran Wood and Paper Industry Co (Chuka). OCC has been repulped according to the common method in paper recycling industry and its freeness, along with that of virgin kraft pulp, were measured. The ...
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This study was aimed to investigate the effects of mixing OCC fibers with mixed hardwoods kraft pulp at Iran Wood and Paper Industry Co (Chuka). OCC has been repulped according to the common method in paper recycling industry and its freeness, along with that of virgin kraft pulp, were measured. The pulps were beaten to reach the required freeness values to make kraft liner paper, and have been then mixed at 10/90, 20/80, 30/70, 50/50 and 70/30 percentage rates of OCC and virgin kraft pulp, respectively. Handsheets were made from each composition and their mechanical and optical properties have been measured, according to required standard test methods, and compared with those of the control (100% virgin kraft pulp), using ANOVA method. Grouping of the mean values was done by Duncan test and normalization equation was computed to determine the best treatment. The results indicate decreasing the values of tensile, tear and burst, folding endurance and density in comparison with those of the control (100% virgin kraft pulp), but bulk, thickness and opacity have been increased. The score belonging to each treatment show to produce paper possessing proper mechanical and optical properties using OCC fibers, the allowed proportion of these fibers is 50 percent.
Pulp and paper
Omid Hosseinzadeh; Ahmad Jahan latibari
Abstract
The influence of pulping temperature and time on strength properties of bagasse soda pulp was investigated. Two cooking temperatures)175ْC,185 ْC (and three cooking times (20,30,40 minutes) were selected .The other variables were kept constant at 18 % NaOH and l/w=8. Tensile strength, tear strength ...
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The influence of pulping temperature and time on strength properties of bagasse soda pulp was investigated. Two cooking temperatures)175ْC,185 ْC (and three cooking times (20,30,40 minutes) were selected .The other variables were kept constant at 18 % NaOH and l/w=8. Tensile strength, tear strength index and folding endurance of hand sheets measured . Factorial experiment and randomized block design was used for statistical analysis and DMRT was used for grouping the means. The results indicate that, application of intermediate cooking intensity produced better pulp than more intense pulping at highest pulping time and temperature. However, more intense pulping produced better folding endurance and pulp prepared at 30 minutes cooking time showed better folding endurance than pulp produced at 20 minutes. The highest tear index was obtain at 185 ْC and 20minutes and lowest at 185ْC and 40 minutes. Results indicate that undamaged fibers will product highest tear index. The highest folding endurance was produced at 175 ْC and 30 minutes and the lowest at 185ْC and 30 minutes .Increasing pulping time reduced tensile index and the highest and lowest tensile index obtained at 20 and 40 minutes pulping time respectively.
Pulp and paper
Hossein Resalti; Morteza Abdolah bik marandi; Ahmad reza Saraeyan
Abstract
The effect of using commercial xylanase enzyme in prebleaching of bagasse kraft pulp was investigated. Xylanase enzyme from Trichoderma viride was added to pulp at various doses of 10, 25 and 50 IU/g pulp for reaction time 2h and then the enzyme treated pulp was bleached in ADED sequences (Acid sulfuric ...
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The effect of using commercial xylanase enzyme in prebleaching of bagasse kraft pulp was investigated. Xylanase enzyme from Trichoderma viride was added to pulp at various doses of 10, 25 and 50 IU/g pulp for reaction time 2h and then the enzyme treated pulp was bleached in ADED sequences (Acid sulfuric +Dioxide chlorine 4, 6, 8, 10% + Alkaline extraction + Dioxide chlorine 2% as available chlorine). The results have shown that with increased dioxide chlorine in D1 bleaching sequence, final brightness of bleached pulp was increased significantly (P<0.01). Furthermore, in the case of treated samples by xylanase enzyme optical properties of bleached pulp such as brightness and opacity were increased significantly (P<0.01). For yellowness, revolution of refiner for distinct pulp freeness and kappa number have shown decreased significantly (P<0.01). Maximum of brightness and minimum of kappa number and yellowness were belong to 25 IU/g pulp treatment that about 10.8, 3.98% and 2.24 unit have difference significantly (P<0.01) as compared with control sample respectively. Maximum of opacity and Minimum was belong to 50IU/g pulp treatment that about 3 and 13.24% have difference significantly as compared with control sample respectively. Regardless of obtained results 25IU/g pulp treatment could be selected as optimal treatment.
Pulp and paper
Noraldin Nazarnezhad; Mohammad taghi Asdolahzadeh
Abstract
This study was investigated the effect of Trametes versicolor on chemimechanical pulp (CMP) delignification. CMP were obtained from Mazanderan wood and paper industries. Circle mats were made from CMP (diameter, 7cm; thickness, 1mm) and fortified with 1g/Lit yeast juice. After sterilized, pulp mats were ...
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This study was investigated the effect of Trametes versicolor on chemimechanical pulp (CMP) delignification. CMP were obtained from Mazanderan wood and paper industries. Circle mats were made from CMP (diameter, 7cm; thickness, 1mm) and fortified with 1g/Lit yeast juice. After sterilized, pulp mats were incubated with tow disks punched from mycelium. The duration of incubate were 5, 10, 15 & 20 days as well as temperature and moisture 25oC and 40%, respectively. Standard hand sheets were made from biodelignification pulp, and was measured mechanical and optical properties. The portion of biodelignification pulp was alkaline extracted under condition of pulp consistency, 10%; temperature, 70oC; time, 80min and 2% sodium hydroxide, and then bleached under conditions of pulp consistency, 10%; temperature, 50oC; time, 60min and 4% hydrogen peroxide. Finally, mechanical and optical properties of standard hand sheet were measured. Results showed optimum time was 10 days that decreased 5.9% lignin. Mechanical properties of treated samples were lower than control samples, but statically were not significant. Optical properties of treated samples were lower than control samples but alkaline extraction and then bleaching with sodium peroxide was increase it.
Pulp and paper
Mohammad Talaeipoor; Habib alah Khademi eslam; Khodadad Malmir chegini
Abstract
Effect of roughness & water absorption of paper and ink characteristics on optical properties was investigated. For this purpose three type of paper and four type of printing ink was used.Then characteristics of paper & ink was measured. Inks on sampled papers Printed and then L, ...
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Effect of roughness & water absorption of paper and ink characteristics on optical properties was investigated. For this purpose three type of paper and four type of printing ink was used.Then characteristics of paper & ink was measured. Inks on sampled papers Printed and then L, a & b was measured. Result indicated that the effect of roughness and water absorption on L, a & b are not significant. But Solid content, PH and particles diameter of four type of ink on L, a & b have significant effect
Pulp and paper
Ahmad Jahan - Latibari; Fardad Golbabaei; Amir Zyadzadeh; Majid Farzi; Arad Vaziryan
Abstract
Fiber length, diameter and lumen diameter and its distribution is determined. Five stalks were randomly selected and after cleaning, the internodes and nodes of each stalk were separated. Each part was depithed manually and then experimental samples were cut from these depithed parts. ...
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Fiber length, diameter and lumen diameter and its distribution is determined. Five stalks were randomly selected and after cleaning, the internodes and nodes of each stalk were separated. Each part was depithed manually and then experimental samples were cut from these depithed parts. Each sample was defibered according to procedure developed by Franklin, 1954. After defibration, fiber length, diameter and lumen diameter of 30 fibers were measured. Each stalk contained 10 nodes and internodes.
Average fiber length of internodes and nodes were determined at 1.004 and 0.802 millimeter respectively. The difference in averages of fiber length for different stalks, different heights in each stalk and between nodes and internodes were significant at 99% level. Fiber length distribution curves for internodes, nodes and all fibers show uniform and symmetrical distribution and the highest points in distribution curves are all at similar fiber length.
Average fiber diameter for internodes and nodes were determined at 16.8 and 20.1 µm respectively which are significantly different at 99% level. Fiber diameter distribution curves for nodes, internodes and all fibers also shows uniform and symmetrical shape, but the highest point for internodes is located at lower fiber diameter than nodes. The average lumen diameter for internodes and nodes were measured at 9.42 and 12.7 respectively which is significantly different at 99% level. The distribution curves for lumen diameter is identical to fiber diameter.
The results indicate that the fiber geometry of cornstalks is similar to hardwoods and other agricultural residues and it can be utilized for production of lower grade pulps such as fluting paper pulp.
Chemistry of wood
saeed mahdavi; masoudreza habibi; Abbas Fakhryan roghani; Kamyar Salehi
Abstract
Oil seed rape (Brassica napus) planting is increasing as the Iranian Ministry of Agriculture Jehad policy to provide supply of oil food in Iran. The objective of this study is utilization of rapeseed straw as a considerable raw material for paper industry whereas there is shortage of lignocellulosic ...
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Oil seed rape (Brassica napus) planting is increasing as the Iranian Ministry of Agriculture Jehad policy to provide supply of oil food in Iran. The objective of this study is utilization of rapeseed straw as a considerable raw material for paper industry whereas there is shortage of lignocellulosic material in Iran. Sampling was carried out from two varieties of oil seed rape, Hiola 401 and PF, based on initial compatibility experiments and yield in Mazandaran province from Baye-colla research station. The results show that at least 4 ton/hect. oven dry rapeseed straws are available. There were significant differences between fiber width, lumen diameter, ash and extractive contents in two varieties. Rapeseed straw as a lignocellulosic material was achieved at 10 score according to the five characteristics consisting of phytology, fiber dimension, fiber yield, chemical components and appearance feature. This means more studies are necessary to make a final assessment.
Pulp and paper
Alireza Khakifiroz; Seeyed Ahmad Mirshokraie; Amir homman Hamasi; Hababalah Khadmieslam; Mohammad Talaei poor
Abstract
Permanent or durable paper is a kind of paper that has a high degree of permanence and is likely to retain the properties which influence readability and document handling when storing in a protected environment for a long period. Permanence depends mainly on the chemical stability of the paper itself. ...
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Permanent or durable paper is a kind of paper that has a high degree of permanence and is likely to retain the properties which influence readability and document handling when storing in a protected environment for a long period. Permanence depends mainly on the chemical stability of the paper itself. Stability may be impaired by chemical reactions involving the paper's own components and by reactive agents from the environment and human being i.e., from air or filing enclosures. Poor chemical stability produces a chain reaction which in long term storage has a pronounced adverse effect on the mechanical or optical properties of the document. The main reactions causing mechanical deterioration are acid hydrolysis and oxidation. Yellowing is due to photochemical and thermal processes. Whatever the fibers used to make paper are longer , alkaline paper making is used , cationic elements such as Fe+2, Fe+3, Cu+2, Mn+2 and kappa number of pulp are minor, it is expected that the paper made is more permanent .In this research imported bleached Eucalyptus kraft pulp was used. The used pulp was refined according to tappi test method T248 cm-85 with PFI mill to reach freeness (300±25) CSF at number of beating revolutions 12000 .Hand sheets were made according to SCAN C25-65 standard with grammage 70.AKD sizing were used 2% oven dry weight of pulp and EDTA as chelating agent was used in concentrations 0 , 0.25 , 0.5 , 0.75 percent. For more assurance deionized water was used. furthermore, 20% calcium carbonate was used as residual alkaline and filler. Then hand sheets were laid under U.V radiation with wavelengths between 330 to 440 nm in 0,10, 20, 30, 40 and 50 hours interval and were conditioned in controlled temperature and relative humidity . pH of Extractive solutions were adjusted between 7 to 7.5 . At last, each strength indices were measured with three measurement frequencies and to compare the amount of mean strengths of produced handsheets, variation analysis (ANOVA) and Duncan test were used with SPSS software and the charts were drawn with Excel software.
Pulp and paper
Said mohammad Mazhari mosavi; Saeed Mahdavi; Syed zyaldin Hosseini; Hossein Resalti; Hossein Usefi
Abstract
This research is aimed to study the possibility of rapeseed straw (Hayolla401) pulping and its paper characteristics, using Soda-AQ process. The average fiber length was found 1.04 millimeter and the average fiber diameter, lumen and thickness were found 28.00, 19.09, and 4.91 micrometer, respectively. ...
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This research is aimed to study the possibility of rapeseed straw (Hayolla401) pulping and its paper characteristics, using Soda-AQ process. The average fiber length was found 1.04 millimeter and the average fiber diameter, lumen and thickness were found 28.00, 19.09, and 4.91 micrometer, respectively. Cellulose, lignin, extractive material (acetone solved) and ash were measured 41.66, 16.00, 1.63, and3.46 percent, respectively. Cooking condition was determined as follow: Soda as 16, 18, and 20 percent on the basis of rapeseed dry straw, temperature was set at 175 and 185 Cº, cooking time was set at 40 and 70 minutes, and straw to liquid ratio was set at 1/8. The amount of anthraquinone added to cooking liquor was 0.2%, based on rapeseed dry straw. Using severe cooking factors caused reduction of yield and Kappa number in both methods. Refining was performed on selected pulps in order to reach 35025 (ml,CSF) freeness. The 60 gr/m² hand sheets were made in order to determine mechanical strength and physical properties. Average thickness, density and bulk is measured at 86.4µ, 0.69gr/cm³ and 1.44cm³/gr respectively. Average tear index, burst index, breaking length and tensile indexare measured at 4.6 mN.m²/gr, 3.5 kpa.m²/gr, 7.4km and 72.6Nm/g respectively.
The results showed that however screen yield of rapeseed straw pulp is low but kappa number and mechanical properties of pulp is suitable,compared with the other agriculture residues, so Rapeseed pulp can be used in paper making industries.
Pulp and paper
Behzad Kord
Abstract
This study is for identifying of the effect of refining intensity on pulp and paper properties made from eucalyptuswood. For this purpose three normal eucalyptus camaldulensis spp trees were randomly cut down from Shastkolateh Experimental Forest located in Gorgan. From each tree, one disk ...
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This study is for identifying of the effect of refining intensity on pulp and paper properties made from eucalyptuswood. For this purpose three normal eucalyptus camaldulensis spp trees were randomly cut down from Shastkolateh Experimental Forest located in Gorgan. From each tree, one disk with 50cm thickness from breast height were selected for pulp making. Then disks converted to chips by chipper, and the chips were cooked by kraft process, the cooking conditions were as following effective alkali 20%, sulfidity 25%, tempreture 190 0C and Time 90min. After cooking and pulping process, the pulp refined with PFI Mill in 5 different intensity with 0 rpm, 500 rpm, 1500 rpm, 2500 rpm and 3500 revelutions. Then, papermaking and measuring the paper properties such as freeness, tensile strength, tear strength, burst strength and density were done. Then data were statisticaly analysed. The results indicated that, there are significant difference between pulp and paper properties made of eucalyptus camaldulensis spp wood with 5 different refining intensity in 95% confident level. As increasing of refining intensity and refining revolutions, freeness and tear strength of paper decreased but tensile strength, burst strength and density of paper incrased. However, the highest value of freeness and tear strength of paper related to refining intensity with 0rpm revelution (without refining) and highest value of tensile strength, burst strength and density of paper related to refining intensity with 3500rpm revelution
Pulp and paper
Mohammad Talaei poor
Abstract
The effect of refining of recycled pulp on the optical, physical and mechanical properties of paper was investigated.The results showed that, except tear strength, all of mechanical strength of paper significantly increases by refining.While, by refining of recycled pulp the brightness increases but ...
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The effect of refining of recycled pulp on the optical, physical and mechanical properties of paper was investigated.The results showed that, except tear strength, all of mechanical strength of paper significantly increases by refining.While, by refining of recycled pulp the brightness increases but the opacity decreases.Also, caliper and roughness of paper decreases.Refining of recycled pulp result in increasing Porosity.
Pulp and paper
Mohammadreza Dehghani Firouzabadi; Afshin Tvasoli; Saeed Mahdavi
Abstract
We studied the possibility of replacing imported long fiber pulp (ILFP) with kenaf bast fiber soda pulp (KBFSP) to improve the quality of paper made with bagasse soda pulp (BSP). To do so, we produced BSP with kappa number 13.5 similar to that prepared by Pars Paper Mill. We also produced KBFSP with ...
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We studied the possibility of replacing imported long fiber pulp (ILFP) with kenaf bast fiber soda pulp (KBFSP) to improve the quality of paper made with bagasse soda pulp (BSP). To do so, we produced BSP with kappa number 13.5 similar to that prepared by Pars Paper Mill. We also produced KBFSP with kappa number 21.6 similar to the unbleached imported ILFP. The yield percent for BSP and KBFSP were respectively 48.9 and 55.6 %. The maximum pulping temperature was 165 °C; alkaline was 20% based on sodium hydroxide and ratio of liquor to dry weight of the raw material was 8:1. All the three pulps were beaten up to a freeness degree of 400 ml, CSF. Amounts of 0, 10, 20 and 30 percent ILFP and KBFSP were mixed with 100, 90, 80 and 70 percent BSP to produce hand sheets. In all cases of KBFSP mixing with BSP, the thickness of the generated hand sheets were higher than those produced through mixing ILFP with BSP while the density was lower. The difference in burst strength and breaking length of a mixture of 30% KBFSP with 70% BSP in the hand sheets were non-significant as compared with those of ILFP and BSP. Tear strength and opacity of mixing 30% KBFSP with 70% BSP were significantly higher than those of the ILFP and BSP with the same mixing ratio. We suggest that KBFSP provides a suitable replacement for ILFP to improve physical and strength properties of paper made with BSP.
Pulp and paper
Aghdas Sadeghi; Ali Abdolkhani; Yahya Hamzeh; Ahmad Mirshokraei; Alinaghi Karimi
Abstract
In this study the pulping of bagasse using TMAH and EDA as organic bases was investigated and compared to conventional Soda and Soda-AQ bagasse pulping. Resulting pulps properties including Kappa number, reject, screen yield of pulp and optical and mechanical properties of handsheets prepared from them ...
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In this study the pulping of bagasse using TMAH and EDA as organic bases was investigated and compared to conventional Soda and Soda-AQ bagasse pulping. Resulting pulps properties including Kappa number, reject, screen yield of pulp and optical and mechanical properties of handsheets prepared from them were determined and compared. Kappa number of TMAH pulp was considerably lower than others. Also, optical properties of TMAH and TMAH-NaOH pulps were considerably higher than Soda and Soda-AQ reference pulps. As well as, addition of EDA to pulping liquor resulted suitable pulp with better properties compared to Soda pulp. Based on the obtained results, it was concluded that the delignificatiom mechanism of TMAH differ to hydroxide ion from NaOH and probably it improves the delignification rate through increasing of lignin degradation and its solubility.
Pulp and paper
Hamid Noori chaparprdy; Ali Ghasemian; Ali Shalbafan; Reza Hajihassani
Abstract
This study has been performed in order to determination of optimum refining of paper made of recovered Kraft liner. Recovered Kraft liner has been prepared from anzali city. After shredding into 5 centimeter pieces, the papers were soaked in distillated water in pail. After 7 days fibers was separated ...
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This study has been performed in order to determination of optimum refining of paper made of recovered Kraft liner. Recovered Kraft liner has been prepared from anzali city. After shredding into 5 centimeter pieces, the papers were soaked in distillated water in pail. After 7 days fibers was separated of each other by disintegrator and freeness for each pulp before and after refining were measured. They were refined in revolutions of 3000, 6000, 9000, 12000 by PFI mill. Hand sheets were made from each revolution in order to TAPPI standard T 205om-95 number, and then were compared with control sample. Analysis of variance of waste papers were conducted using completely randomized design, then mean values were compared, using Duncan’s test, and finally the normalization equations were used to determine the best sample. Results showed that increasing of refining revolution increased strength of burst, tensile and brightness but decrease freeness, thickness and tear strength at product. Normalization equations showed that the best papers made from refining revolution of 9000.
Pulp and paper
Yahya Hamzeh; Mohammad hassan Ekhtera; Ali Abdolkhani; Sohila Ezadyar; Kambiz Pourtahmasi
Abstract
In this study the effects of several parameters on the sizing efficiency of test liner using poly aluminum chloride and rosin under neutral condition in reverse and premixing sizing processes were investigated. The results indicated that the individual effects of poly aluminum chloride amount, rosin ...
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In this study the effects of several parameters on the sizing efficiency of test liner using poly aluminum chloride and rosin under neutral condition in reverse and premixing sizing processes were investigated. The results indicated that the individual effects of poly aluminum chloride amount, rosin amount, interval time as well as interaction effect of poly aluminum chloride -rosin amounts in both sizing processes affect significantly sizing performance. The most important variable was the poly aluminum chloride amount. The effect of poly aluminum chloride amount on the sizing efficiency depended on the properties of fiber surfaces. This study showed that the interval time on the sizing efficiency is significant. To obtain an identical degree of sizing, it is possible decrease the amount of poly aluminum chloride and rosin amounts by increasing the interval time. In addition, the results confirmed two different mechanisms involved in the premixing sizing process.
Pulp and paper
Amir mohsen Nazeri; Mohammad Talaeipoor; Seeyed Ahmad Mirshokraie
Abstract
The present study deals with effects of CMP fines on optical and physical properties of newsprint papers, for which, different batches for CMP fines (0%, 10%. 20%. 30%) of totally 80% pulp is taken, Where the remaining 20% of imported long fiber pulp was taken as fixed amount .
The study ...
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The present study deals with effects of CMP fines on optical and physical properties of newsprint papers, for which, different batches for CMP fines (0%, 10%. 20%. 30%) of totally 80% pulp is taken, Where the remaining 20% of imported long fiber pulp was taken as fixed amount .
The study focused on surving the effects of CMP fines on optical and physical properties of newsprint paper ,after mixing the pulps and making the handsheets .
Generally, the results show the increase in CMP fine amount lead to increase ,Air Resistance and Opacity and decrease Caliper and Roughness, Also that changes in CMP fines has no effect on Brightness .