Pulp and paper
Jaber Hossein zade; Ali Abdolkhani; Mohammad Emami nasab; Hamid Khodabandeh lo; Mohammad Ahmadi
Abstract
In this research Tension Wood (TW) and Normal Wood (NW) of Poplar were analyzed for pulp production using Kraft pulping process. After preparing samples, Biometric characteristics of the NW and TW fibers were measured and samples were converted to pulp. Pulp hand sheets mechanical and physical properties ...
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In this research Tension Wood (TW) and Normal Wood (NW) of Poplar were analyzed for pulp production using Kraft pulping process. After preparing samples, Biometric characteristics of the NW and TW fibers were measured and samples were converted to pulp. Pulp hand sheets mechanical and physical properties were measured and results were showed that NW fibers compared to TW fibers had a higher Rankle coefficient and aspect ratio. However the flexibility of NW fibers was better than TW fibers. Based on Results, although TW pulp yield was 13 percent greater than NW pulp yield but kappa number in TW was 45 percent lower than NW. Mechanical and physical properties of hand sheets indicated that the tensile and burst strengths of tension wood were comparatively lower than that of normal wood. Also the papers produced by equally mixture of TW fibers and NW fibers were showed higher tensile and burst strengths. Optical and color analyses of samples were showed an improvement in brightness and whiteness for TW hand sheets compared to NW papers. General speaking results were showed that presence of TW fibers inside pulp had not a significant effect on quality of produced pulp and papers.
Pulp and paper
mojtaba goli; Ghasem Asadpur; Saeed Mahdavi; Abdollah Barimani
Abstract
Importing of wood is a solution to supplying raw material in the Iranian paper industry because of wood shortage. Therefore, the effect of mixing the imported aspen roundwood with the two hardwood native forest species including hornbeam and beech were perused on the optical and mechanical properties ...
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Importing of wood is a solution to supplying raw material in the Iranian paper industry because of wood shortage. Therefore, the effect of mixing the imported aspen roundwood with the two hardwood native forest species including hornbeam and beech were perused on the optical and mechanical properties of CMP pulp. Cooking constant conditions consist of maximum temperature were 170 °C with a liquor-to-wood ratio (L/W) of 7, and chemical content of 20% based on the oven-dry weight of the wood chips. CMP pulps were prepared at different cooking times of 30 to 120 minutes using 20, 30, 40, 60, and 100% aspen wood in combination with the two species to achieve the yield of nearly 85%. Standard laboratory handsheets were made after pulp refining by 300 ml CSF, and then the strengths and optical properties were measured. Statistical analysis of result showed that there were significant differences among of the properties of CMP pulps by increasing the aspen wood ratio. All the properties have been improved except opacity paper. The required strength of newsprint and printing/writing paper made in Mazandaran wood and paper industries (MWPI) could be achieved by mixing of 20 and 30% imported aspen wood to the native species used in currently, respectively.
Pulp and paper
Hamed Sharifi tasco; yahya hamzeh; shademan pourmousa
Abstract
In this study dispersed deinked pulp (DIP) of Latif Company which includes a mixture of straw printers, mixed office waste (MOW) and mechanical recycle paper was used to investigate the effect of bleaching variables on pulp and paper properties. Six variables of bleaching process including the amount ...
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In this study dispersed deinked pulp (DIP) of Latif Company which includes a mixture of straw printers, mixed office waste (MOW) and mechanical recycle paper was used to investigate the effect of bleaching variables on pulp and paper properties. Six variables of bleaching process including the amount of hydrogen peroxide, sodium hydroxide, and sodium silicate, bleaching time, bleaching temperature and final pH were optimized in order to improve wet and dry tensile index of handsheet. Design Expert software was used for analyzing and modeling. Results in from of the central composite design (CCD) were investigated and response surface methodology (RSM) was modeled and analyzed. Optimized wet and dry tensile were obtained by appling 1.55% hydrogen peroxide, 1.55% sodium hydroxide and 1.55% silicate, 90 minutes bleaching time, 83 0C bleaching temperature, and final pH equal to 8.5. The result showed that bleaching variables affect significantly the optical properties sample as well as mechanical strength of paper, and also dry and wet tensile strengths can be improved by optimization of bleaching condition.
Pulp and paper
Hosein Valayi; Ahmad Jahan Latibari
Abstract
Strength properties and the yield of soda and soda-ethanol pulps produced using hornbeam, beech and poplar woods were investigated. Soda pulps were produced applying 20% active alkali and the soda-ethanol pulps were made using 10% active alkali and 50% ethanol. The pulping temperature was constant at ...
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Strength properties and the yield of soda and soda-ethanol pulps produced using hornbeam, beech and poplar woods were investigated. Soda pulps were produced applying 20% active alkali and the soda-ethanol pulps were made using 10% active alkali and 50% ethanol. The pulping temperature was constant at 175 C and the soda pulping time was selected at 120 minutes and the soda-ethanol pulping times were 120 and 180 minutes. The highest accepted pulping yield at 58.54% was reached using soda pulping on poplar wood and the lowest yield (49.29%) was related to soda-ethanol pulp produced from beech wood applying 180 minutes pulping time. The accepted yield of soda-ethanol pulping was low, but the kappa numbers of these pulps were almost 20 units lower than soda pulps. The strength properties of soda-ethanol pulps were superior to soda pulps and the difference was statistically significant at 99% confidence level. The results of this study indicated that the delignification of soda-ethanol pulping process is faster than soda pulping from the selected hardwoods especially poplar wood.
Pulp and paper
Ramin Veisi
Abstract
This research and aim was using Bamboo and Reed CMP pulp for newsprint production. For this purpose, some chips of bamboo stem in the west of Mazandaran were randomly chosen. Then CMP Pulps were prepared at the yield 85%in 120 minutes(Bamboo) and 31 minutes(Reed), by using cooking conditions of Wood ...
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This research and aim was using Bamboo and Reed CMP pulp for newsprint production. For this purpose, some chips of bamboo stem in the west of Mazandaran were randomly chosen. Then CMP Pulps were prepared at the yield 85%in 120 minutes(Bamboo) and 31 minutes(Reed), by using cooking conditions of Wood and Paper Industries of Mazandaran 60 gr/m2 newsprint handsheets were prepared from the Bamboo and Reed CMP and Mill(MWPI) CMP pulps, first in a separate and then mixed way with 25,50,75 percents. Then the optical and mechanical properties were measured and compared according by using TAPPI Standard test methods. The results showed that the most strength of the burst, breaking length, tensile, tear strength, yellowness and opacity were in the handsheets obtained from 100% the bamboo CMP pulp and the lowest strength (except brightness) was in Reed CMP pulp. The results also pointed out that the above-mentioned all strengths (except brightness) can be improved by using 25-100% of the bamboo CMP pulp, too. The results also indicated that 25-100% of the bamboo CMP pulp and 25% of the Reed CMP pulp can use for newsprint production.
Pulp and paper
Esmaeil Rasooly Garmaroody; Iraj Mohammadi
Abstract
Bio-kraft pulp made from Hornbeam chips fungal pre-treated (1, 2 and 3 weeks) was used for investigation of its bleachability by DED sequence. Before and after of each step in mentioned sequence, pulps and bleaching spent liquors characterized and then 60g/m2 standards handsheets made from above pulps ...
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Bio-kraft pulp made from Hornbeam chips fungal pre-treated (1, 2 and 3 weeks) was used for investigation of its bleachability by DED sequence. Before and after of each step in mentioned sequence, pulps and bleaching spent liquors characterized and then 60g/m2 standards handsheets made from above pulps and tested in optical properties. Results shown that by increasing in chips pre-treatment time, lignin contents of pulps is more lacked by passing of DED sequence steps. Also, pulp viscosity and DP are lacked by increasing in pre-treatment time simultaneously increasing in hexenuronic acids and this is due to not full selectivity of fungle. Fungal pre-treatment of chips has not significant effect on brightness of unbleached pulps but due to softening in lignin structure, could be improved bleaching process as with increasing in pre-treatment time brightness increased and opacity decreased in final paper. Generally, it seems that Hornbeam chips fungal pre-treatment has good efficiency on its pulp bleachability although chemical consumption in bleaching increased up to 3 weeks pre-treatment.
Pulp and paper
alireza shakeri; monireh imani; farshad miraki
Abstract
Cellulose is one of the most abundant natural biopolymer on earth is renewable, biodegradable and non-toxic. Micro and Nano-scale cellulose fibers and their applications in composite materials due to their high strength and stiffness combined with low weight, biodegradability and renewability has attracted ...
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Cellulose is one of the most abundant natural biopolymer on earth is renewable, biodegradable and non-toxic. Micro and Nano-scale cellulose fibers and their applications in composite materials due to their high strength and stiffness combined with low weight, biodegradability and renewability has attracted considerable attention. In this study, Micro-crystalline cellulose (MCC) of the skin of the cotton plant by acid hydrolysis in 2N hydrochloric acid to acid ratio of dough the Nano-crystalline (NCC) were prepared by chemical methods. Effect of hydrolysis conditions on properties such as the crystallinity and crystal size Micro and Nanocrystals cellulose with measurement range into the infra-red February (FT-IR), X-ray diffraction (XRD) were reviewed and The shape and size of the samples by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were studied. Fiber analysis using x-ray showed that increasing the amount of acid in the crystallinity of cotton cellulose Micro- crystalline increase the crystal size does not change Lower moisture uptake. Cotton cellulose Nanocrystals and crystal size greater than Micro- crystalline size were reported.
Pulp and paper
Afshin Veisi; Saeed Mahdavi; Mohammad Talaeipoor
Abstract
In this study, production of bleached chemical- mechanical pulp from wheat straw for newsprint papermaking was investigated. Wheat straw for pulping was obtained from Lorestan province. Wheat straw CMP pulp was prepared at 120, 140, and 160 °C temperature, 45 minute time, 10, 12, and 14% chemicals ...
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In this study, production of bleached chemical- mechanical pulp from wheat straw for newsprint papermaking was investigated. Wheat straw for pulping was obtained from Lorestan province. Wheat straw CMP pulp was prepared at 120, 140, and 160 °C temperature, 45 minute time, 10, 12, and 14% chemicals charge and 10:1 cooking liquor and straw ratio. The yield after defibration treatment varied between 56.5% and 72.5%. Two optimum pulps bleached by TCF method applying 2% and 3% NaOH, 1.5% and 2% H2O2, and 60 and 120 minutes bleaching time. One way analysis variance method showed that bleaching time had the most significant effect on optical properties of handsheet. Applying 3% (based on oven dry weight of the unbleached pulp) NaOH, 2% H2O2, and 120 min. in bleaching improved the brightness and opacity to 52.9%, and 79.5% ISO, respectively. Optimum pulp strengths including tensile, burst and tear indices were measured 43.87 Nm/g, 2.18 kPa.m2/g, and 8.46 mN.m2/g, respectively. All the strengths were higher than newsprint paper strength produced by Mazandaran wood and paper and Korean companies.
Pulp and paper
masoumeh mollaei; Mohammad Azadfallah; Yahya Hamzeh; faramarz khodaian chegini
Abstract
The Effect of Chitosan - Poly (vinyl alcohol) Coatings on Strength and Barrier Properties of Packaging PaperAbstract In this research the mechanical and barrier properties of hand-sheets made of virgin and recycled fibers were studied after coating by chitosan and poly (vinyl alcohol) polymer blends. ...
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The Effect of Chitosan - Poly (vinyl alcohol) Coatings on Strength and Barrier Properties of Packaging PaperAbstract In this research the mechanical and barrier properties of hand-sheets made of virgin and recycled fibers were studied after coating by chitosan and poly (vinyl alcohol) polymer blends. Therefore to evaluate coatings effects on barrier properties, water vapor transmission rate (WVTR), water absorbance, air resistance and grease proof of coated papers were determined. Moreover, mechanical strength including tensile strength and burst strength were measured. According to the results, the barrier properties and mechanical strength of coated papers improved dramatically than uncoated ones. The best results in WVTR and mechanical strength tests were obtained for coatings with the same ratio of polymers. On the other hand, coating with 75%chitosan - 25% poly (vinyl alcohol) composition exhibited excellent resistance against the grease penetration and water absorption.Keywords: Coating, chitosan, poly (vinyl alcohol), barrier properties, mechanical strength
Pulp and paper
Noraldin Nazarnezhad; Naser Rasol pour hedayati; Omid Ramazani
Abstract
Chitosan is known as a natural polymer which improves strengths of papers. So, in this study investigated improvement of chitosan absorption on modified craft fibers and increase its efficiency. The effects of chitosan were experimented in three levels of 0%, 0.75% and 1.25% on modified kraft fibers ...
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Chitosan is known as a natural polymer which improves strengths of papers. So, in this study investigated improvement of chitosan absorption on modified craft fibers and increase its efficiency. The effects of chitosan were experimented in three levels of 0%, 0.75% and 1.25% on modified kraft fibers surfaces with 3% hydrogen peroxide in different pH levels (5.5, 7 and 8.5). The results showed that chitosan had better performance at low dosages and alkaline conditions. Also surface fibers modification by hydrogen peroxide caused increase of carboxyl groups and fibers anionic charge. Fibers anionic charge with participant of chitosan formed a dual system. The apparent density increased from acidic pH to alkaline. As, the highest apparent density were reached in alkaline pH and 0.75 % of chitosan. Also, tensile index and burst index of paper were reached in alkaline pH and 0.75 % of chitosan. Whereas, chitosan and the surface modified fibers of kraft pulp did not have a significant level on the tear index
Pulp and paper
Ali Barzan; Hossein Resalati; Ghasem Asadpour atoei
Abstract
After water purification and softening, a lot of calcium carbonate with other impurities produce and these byproducts gather and bury as mineral sludge.In this research, The quality of calcium carbonate from water softening process in mazandran wood and paper industry (MWPI) mill and effects of loading ...
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After water purification and softening, a lot of calcium carbonate with other impurities produce and these byproducts gather and bury as mineral sludge.In this research, The quality of calcium carbonate from water softening process in mazandran wood and paper industry (MWPI) mill and effects of loading of this byproduct on fine paper production was investigated and the results were compared with other industrial fillers like grounded calcium carbonate(GCC) and precipitated calcium carbonate(PCC) and also china clay (kaolin).From the paper structural viewpoint , the fine paper that filled with water softening calcium carbonate (derived after water softening process) have more bulk(bulkier) and more porous and rougher surface compare to fine papers that filled with the common industrial fillers.From the paper strength properties viewpoint , the fine paper that filled with water softening calcium carbonate have less decrease in tensile and burst strength but have not suitable tear strength properties. From the paper optical properties viewpoint, the fine paper that filled with water softening calcium carbonate, because of particles size and impurities of this filler have the least light scattering coefficient and consequently have less brightness and opacity.Adding of 10 and 20 percent precipitated calcium carbonate to by water softening calcium carbonate cause paper porosity and strength decreasing but the optical properties of hand sheets was increased.
Pulp and paper
Farzaneh Shiralizadeh; Sahab Hejazi; Mohammad Ahmadi
Abstract
In this research, rice straw was used as raw material. Potassium hydroxide was combined with monoethanolamine (MEA) as liquor. In another processes NaOH/Na2So3, KOH/K2So3 and KOH 14% was used as references pulp. The results showed that using pure MEA(15%) produced the highest yield and the highest kappa ...
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In this research, rice straw was used as raw material. Potassium hydroxide was combined with monoethanolamine (MEA) as liquor. In another processes NaOH/Na2So3, KOH/K2So3 and KOH 14% was used as references pulp. The results showed that using pure MEA(15%) produced the highest yield and the highest kappa number. By using potassium hydroxide as a additive agent in MEA pulping, the amount of reject, yield and kappa number was decreased and the lowest yield and the lowest kappa number relevant to MEA(15%) combined with KOH (40%). In addition, in KOH pulping observed that, with increasing concentration of MEA, as additive agent, the amount of total yield increased but the kappa number and reject content was decreased. Results showed that the highest tensile index and tear index were relevant to MEA (15%) combined with KOH (20%) and the highest burs index relevant to NaOH/Na2SO3 treatment. According to the optical properties, it was found that the highest brightness was achieved in K2SO3/KOH. The highest opacity relevant to the KOH14% .The result shows that MEA process in combined with Potassium hydroxide can be done success fully on rice straw and properties of pulp production, specially in aspect of mechanical strength, in term of combination is superior than soda and Potassium hydroxide process
Pulp and paper
Ramin Veisi; Iman Khajeh ali
Abstract
This study and it aim was accomplished on extraction, identification and removal of metallic ions and resins in bleached Bagass pulp by ECF stages. For this purpose, the samples were randomly selected from soda unbleached pulp of Pars mill. The first, pulp flour provided and measured ash and extractive ...
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This study and it aim was accomplished on extraction, identification and removal of metallic ions and resins in bleached Bagass pulp by ECF stages. For this purpose, the samples were randomly selected from soda unbleached pulp of Pars mill. The first, pulp flour provided and measured ash and extractive percent by the TAPPI standards. Then the mineral compounds dissolved in 65% nitric acid and the mineral compounds of pulps identificated by Atomic adsorption method. The results of this study showed that the most of Pb, Cu, Zn ions were in H2O2 bleached pulp, the most of Ni ion in OD(Ep)P stage and the most of Fe ion in unbleached soda pulp. The results showed that OD(Ep)D stage decrease Fe ion and EH stage decrease Ni, Cu and Zn ions in pulps. The results of GC-MS diagram showed that 35 compounds were identified in unbleached soda pulp after cooking, that 1,2-Benzendicarboxylic acid, Hexadecanoic acid, Hexadecan, Octadecan, p-Xylene, 4-Hydroxy-4-Methyl-2-Pantanone,Ethylbenzen and Dodecan were important chemical components in samples. In generally, 17,12 and 14 compounds were identified in EH, OD(Ep)P and OD(Ep)D bleaching stages, respectively, so that, 1,2-Benzendicarboxylic acid and p-Xylene were 2 common and important chemical components in all samples and Octadecan and 9-Dodecanoic acid remove as two components from pulps after bleaching, too. The results showed that EH, OD(Ep)P and OD(Ep)D bleaching stages were very important in bleaching, removal of chemical components and brightness stability of soda pulps.
Pulp and paper
Mostafa Nikkhah Dafchahi; Hossein Resalati
Abstract
This research was performed to evaluate the potential of acid pre-hydrolysis soda-AQ process for the production of dissolving pulp including high α-cellulose content from Populus deltoides. To achieve the aim, a pre-hydrolysis liquor containing 0.06% acid sulfuric, soda-AQ pulping, and OD0ED1 bleaching ...
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This research was performed to evaluate the potential of acid pre-hydrolysis soda-AQ process for the production of dissolving pulp including high α-cellulose content from Populus deltoides. To achieve the aim, a pre-hydrolysis liquor containing 0.06% acid sulfuric, soda-AQ pulping, and OD0ED1 bleaching sequence were used. The results show that using at least 0.40 kappa factor at D0 stage was necessary to gain access a high quality dissolving pulp including characteristics like having brightness level and α-cellulose content higher than 86% and 98%, respectively. A kappa reduction of 40.3% was achieved by performing a single stage oxygen delignification after soda-AQ pulping to drop kappa number of pulp from 14.1 to 8.4 prior to entrancing the pulp into the final bleaching stage. The results illustrated that producing acid pre-hydrolyzed soda-AQ dissolving pulp including high α-cellulose content and brightness, and even viscosity is completely feasible through controlling and optimizing the acid pre-hydrolysis, pulping, oxygen delignification stages, and D0ED1 bleaching sequence.
Pulp and paper
Moghadaseh Akbari; Nadia Kabodi torabi; Hossein Rrsalati; Gasem Asadpour atoei; Mohammad reza Dehghani firozabadi
Abstract
Aim of this study is precipitated calcium carbonate cationic modification and comparison of impact of using its with conventional filler (unmodified) on strength properties of paper. One of the defects of adding fillers to paper is decreasing of mechanical strength of paper because of reduction in bonding ...
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Aim of this study is precipitated calcium carbonate cationic modification and comparison of impact of using its with conventional filler (unmodified) on strength properties of paper. One of the defects of adding fillers to paper is decreasing of mechanical strength of paper because of reduction in bonding area between fibers. In this study whit purpose of maintaining the strength of paper, and change the surface charge of precipitated calcium carbonate and replace it with conventional fillers are used.in this research with aim of precipitated calcium carbonate and replacing it with conventional filler was used. Condition of cationic precipitated calcium carbonate preparation was 90 ċ temperature, 3 hours time and 55% water content of cooking process. loading amount of starch was 9, 12 and 15 percent based on precipitated calcium carbonate weight.Papers made at three level: 10, 16, 30 percent of filler in paper sheets contain conventional fillers were compared. Results indicated that papers containing modified-filler have more values of retention rather than those with unmodified filler, both in 20% and 30% filler dosages.papers contained cationic filler have more mechanical strength index in respect of papers contained conventional fillers.
Pulp and paper
vida haji Aghaei; Seeyed Ahmad Mirshokraie; Tayyebe partovi
Abstract
In this study, the structure of Soda (soluble fraction in ethanol) and Dioxane lignins of bagasse were studied by using derivatization followed by reductive cleavage (DFRC) method and some techniques including gel permeation chromatography, gas chromatography-mass spectrometry and 13C-nuclear magnetic ...
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In this study, the structure of Soda (soluble fraction in ethanol) and Dioxane lignins of bagasse were studied by using derivatization followed by reductive cleavage (DFRC) method and some techniques including gel permeation chromatography, gas chromatography-mass spectrometry and 13C-nuclear magnetic resonance spectroscopy and the results were compared. These comparative results show that the main monomeric compounds are obtained from the cleavage of β-O-4 bonds of lignins. The components obtained from Dioxane lignin and Soda lignin are guaiacyl, syringyl and p-hydroxyphenyl structures with different proportions. However, some differences have been observed in both lignins, including a variety of structural units in Dioxane lignin is greater than Soda lignin. In other words, soda lignin degradation and the structural components has become closer together and are more uniform structures. The average molecular weight of Dioxane lignin, is greater than Soda lignin, which is due to Soda lignin wide chemical degradation during industrial pulping processes and therefore it has less dense structure. These observations indicate that a mild method for lignin separation from a lignocellulosic material caused less damage and changes in lignin structure. Therefore, in structural studies, Dioxane lignin can actually be used as an appropriate representative of the lignin.
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.
Pulp and paper
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.
