Pulp and paper
Pejman Rezayati Charani; Ahmad Azizi. Mossello
Abstract
The use of old corrugated container (OCC) is considered an effective solution by the paper industries in paper and paperboard productions bearing environmental and economic reasons. The strength properties of pulp made from recycled paper is weaker than the original pulp for various reasons, such as ...
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The use of old corrugated container (OCC) is considered an effective solution by the paper industries in paper and paperboard productions bearing environmental and economic reasons. The strength properties of pulp made from recycled paper is weaker than the original pulp for various reasons, such as hornification. Therefore, various methods as adding strength enhancing materials and mechanical treatments are used to improve the quality of them. Because of little amount of production, many of the paper recyclers have limitation in investment of using mechanical treatments (refiners) in their production line. In this research, using cationic starch and cellulose nanofibers(CNF) was investigated as strengthen additives and as an alternative for mechanical refining in the paper and paperboard production from OCC. In this study, cationic starch in one level (2%) and cellulose nanofibers in 3 levels (2, 4, 6%) were used and compared to control (refined and non-refined) samples. Results showed that 2% CS and 4% CNF improved the tensile and burst indices same as or more than refining of pulp, while the pulp dewatering time and paper density were equal. Therefore, the aforementioned conditions are recommended as a substitute for refining in small units of waste paper recycling for paper and paperboard production.
Pulp and paper
Hossein Resalati; Mostafa Nikkhah Dafchahi
Abstract
One of the drawbacks of utilizing non-forest fast growing species of Poplar as raw materials to produce newsprint in Mazandran Pulp and Paper Mill is fairly low bulk and opacity of produced paper at the yield of 85% (current CMP yield of the Mill). In this research work, the effect of process parameters ...
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One of the drawbacks of utilizing non-forest fast growing species of Poplar as raw materials to produce newsprint in Mazandran Pulp and Paper Mill is fairly low bulk and opacity of produced paper at the yield of 85% (current CMP yield of the Mill). In this research work, the effect of process parameters (cooking yield and freeness) on the optical and mechanical properties of chemi-mechanical pulp was investigated. The chemi-mechanical pulps of poplar was prepared at four various levels of cooking yield, through changing the cooking time, and their properties at different level of freeness were evaluated in comparison with the control sample of Mazandran Pulp and Paper Mill (75% hornbeam and 25% beech). Strength properties of the paper pulps stemmed from the cooking yields of 85.25% to 90.4% were higher and more favorable than the control sample. By contrast, the strength properties of the produced paper pulp from the cooking yield of 94.6% were inferior to prepared paper pulp from the control sample. According to the results, there is the possibility of significant improvement of the strength properties, opacity and bulk of the chemi-mechanical pulps of poplar trough controlling the process parameters like cooking yield and freeness to utilize it as raw material of newsprint production in Mazandran Pulp and Paper Mill.
Pulp and paper
Hossein Resalati; Mostafa Nikkhah Dafchahi
Abstract
Due to shortage of harvestable forest wood in Iran, the potential of CMP pulp production from various species of salix (alba, fragilis and aegyptica), in comparison with populus deltoides, was investigated across this research work. The cooking liqour of Mazandaran wood and paper Mill, consisting of ...
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Due to shortage of harvestable forest wood in Iran, the potential of CMP pulp production from various species of salix (alba, fragilis and aegyptica), in comparison with populus deltoides, was investigated across this research work. The cooking liqour of Mazandaran wood and paper Mill, consisting of 50:50 ratios of sodium sulfite and sodium bisulfite, and hydrogen peroxide, were used for Chemical treatment and bleaching of the pulps, respectively. The results showed that the paper pulps of fragilis salix and alba salix had higher bulk and lower opacity than other species, respectively. From the strength properties point of view, the highest and lowest tensile strength of produced papers were related to alba and fragilis species, and, the highest and lowest burst and tear strength of the prepared papers have belonged to Salix aegyptica and Populus species, respectively. The data have shown that Salix species have a good pothential to be used as raw material to produce CMP pulp at the cooking yield of 85%. According to the results of this research work, alba salix and aegyptica salix are in first and the second priority to produce CMP pulp ,at the cooking yield of 85%, respectively.
Pulp and paper
Hamid reza Rodi; Hasibeh Saeidi
Abstract
Current study was done with the aim of investigating the effect of polymeric multilayers of cationic starch and anionic starch upon CMP fibers using layer-by-layer technique on its pulp and paper properties. Consecutive cationic and anionic starches layering experiments (respectively 1% and 0.5% dose ...
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Current study was done with the aim of investigating the effect of polymeric multilayers of cationic starch and anionic starch upon CMP fibers using layer-by-layer technique on its pulp and paper properties. Consecutive cationic and anionic starches layering experiments (respectively 1% and 0.5% dose of each starch based on oven-dry fibers) with layering time of about 10 minutes were conducted to assemble one to five successive ionic starches onto CMP fibers. Pulp properties including: freeness, water retention value and zeta potential were examined. Then, handsheets with basis weight of about 60 g/m2 were prepared and their properties were analyzed. Succeeding variation of zeta potential designated formation of successive layers of starches onto the CMP fibers. Furthermore, pulp freeness and water retention value has been enlarged by increasing the number of formed layers. The results of paper properties analysis showed that bonding-ability of fibers including tensile index and burst index have been considerably improved. The prepared SEM micrographs indicated of making more bonds between fibers due to the higher absorption of cationic starch.
Pulp and paper
fatemeh asadi; Noradin Nazarneghad; Ghasem Asadpoor atoeei
Abstract
Nowdays, algae considering marine ecosystem are regarded as producers and the first continuum that receives solar energy. Hence, they ensure the needed energy for the aquatic organism living. In global herbal division, algae have 1800 genus and 21000 types. Because of their presence in air rather than ...
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Nowdays, algae considering marine ecosystem are regarded as producers and the first continuum that receives solar energy. Hence, they ensure the needed energy for the aquatic organism living. In global herbal division, algae have 1800 genus and 21000 types. Because of their presence in air rather than underground water, algae allocate larger arena to themselves in comparise to other herbage. Based on accomplished studies, it is rated that algae have more than 7000 types in terms of biological diversity. Algae are used a lot. They are consumed in food industry, dung preparation, medicinal consumption and etc. In this study the green algae nanocellulose was used to improve CMP resistance.For the preparation of pure cellulose, algae samples initially affected the soda process and then were affected by bleaching sequence.. Next, the obtained cellulose has been converted to Nano-cellulose by using ultrasonic method. Nano-cellulose from cladophora algae was mixed with CMP in the ratios of 2, 5 and 8 percent. Finally, handmade paper was made and its resistive (strengh) properties were studied and compared with the pure hardwood CMP pulp. The results revealed that 8% treatment group had the highest density, tensile strength, burst strength, and control group had the lowest amount. Furthermore, the highest tear strength was related to control group; while, the lowest tear strength was for 8% treatment group.
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.
Porya Rezaei niaraki; Ahmad Jahan Latibari; Azhang Tajadini; Mehran Roohnia
Abstract
The influence of fiber lignin content and the dosage of coupling agent on the strength and physical properties of cellulosic fiber-polypropylene composite were investigated. The old corrugated container (OCC) fibers were delignified using sodium hydroxide to reach the lignin content of 2.7, 3.78, 5.26 ...
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The influence of fiber lignin content and the dosage of coupling agent on the strength and physical properties of cellulosic fiber-polypropylene composite were investigated. The old corrugated container (OCC) fibers were delignified using sodium hydroxide to reach the lignin content of 2.7, 3.78, 5.26 and 7%. Fibers were compounded with polypropylene by extrusion process using 20% fibers and 77% PP and the extrudate was cooled and grinded to fine granulates before injection molding. MAPP coupling agent was applied at three different levels (1, 2 and 3 percent based on the total weight of the composite). The strength properties of the composites were measured using relevant ASTM test methods and the results were statistically analyzed using factorial experiment under complete randomized design. The impact of fiber lignin content of flexural strength of composite was statistically significant at 98 percent significance level and the lowest and highest values of flexural strength of composite were measured at 3.78 percent and 7 percent lignin content of fiber. The interactive effect of fiber lignin and MAPP on the tensile strength and flexural modulus of elasticity of the composite showed that at lower values of lignin and higher dosage of MAPP, these properties are 38.7 and 3438 MPa respectively. Other strength values of the composites were also improved and at lower content of lignin and increaing dosages of the MAPP, the impact strength of the composites was increased from 52.82 J/m to 60.26 J/m.
Soodeh Zhand; Masih Masoudifar; Ahmad reza Saraeian; Ali Ghasemian
Abstract
The purpose of this study was to compare the properties of wheat straw (Zagros sp) collected in Golestan province NSSC pulp under alkaline pretreatment with 1% sodium hydroxide and boiling pretreatment. Wheat Straw pretreatment with 1% sodium hydroxide and hot water at water to straw ration of 10 to ...
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The purpose of this study was to compare the properties of wheat straw (Zagros sp) collected in Golestan province NSSC pulp under alkaline pretreatment with 1% sodium hydroxide and boiling pretreatment. Wheat Straw pretreatment with 1% sodium hydroxide and hot water at water to straw ration of 10 to 1 was conducted at 70ْC for half an hour. NSSC pulping was carried out at constant pulping condition including liquor to straw ratio of 5:1, maximum temperature at 160ºC for 30 minutes. In order to study the effect of sodium hydroxide on strength properties of paper in some cases only Na2S03 was used. After pulping, defibration was carried out by laboratory refiner to reach 380±25ml (CSF). Sixty gram/m² hand sheets were prepared from each pulp. The strength properties were determined according to TAPPI standard. Results showed that with the exception of RCT strength, pretreatment had significant effect on increasing the strength properties of papers and by alkaline pretreatment, brightness of the pulps decreased and tensile strength, burst strength, breaking length, stiffness and density increased. Using chemical pretreatment especially sodium hydroxide resulted in reduction in yield and brightness level and improvement in strength of the pulps.
Amir Nourbakgsh
Abstract
Two recycled polymers (rHTPE and rPP) combined with baggase fibers were used as the reinforcing material to improve the mechanical properties of wood plastic nanoclay composite. The amount of baggase fibers varied at three levels (25, 35 and, 45 percent). Two recycled polymers (rPP and rHDPE) were used ...
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Two recycled polymers (rHTPE and rPP) combined with baggase fibers were used as the reinforcing material to improve the mechanical properties of wood plastic nanoclay composite. The amount of baggase fibers varied at three levels (25, 35 and, 45 percent). Two recycled polymers (rPP and rHDPE) were used as polymer matrix. Tensile, flexural and impact strength properties were measured according to ASTM standard tests. Scanning electron microscopy (SEM) and X-Ray Diffraction (XRD) was performed to interpret the results. The results were statistically analyzed using factorial experimental under completely randomized block design and the averages were compared using DMRT. The application of 35 percent bagasse fibers as compared with 25 and 45 percent increased the strength of wood plastics composites. However, higher impact strength was reached using 25% bagasse fibers as compared with either 35 or 45% bagasse fibers. rHDPE nano-clay composite showed higher tensile, flexural and impact properties compared with rPP. Imaging the morphology of nano-clay by X-Ray diffraction and scanning electron microscopy showed the distribution of nano-clay particles in polymer structure and intercalation was observed.
Mahid Farzi; Ali akbar Enayati; Davood Parsa paghoh
Abstract
In this investigation, soda pulps from old rags applying three pulping times (60, 120 and 180 minutes ) and three levels of active alkali ( 6,8, and 10% NaOH based on OD weight of rag) and pulping temperature of 125º C were produced. Liquor to rag ratio was kept constant at 11:1(based on the ...
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In this investigation, soda pulps from old rags applying three pulping times (60, 120 and 180 minutes ) and three levels of active alkali ( 6,8, and 10% NaOH based on OD weight of rag) and pulping temperature of 125º C were produced. Liquor to rag ratio was kept constant at 11:1(based on the weight of the rag). After pulping, hand sheets were made and then both strength and optical properties of hand sheets were measured. It was revealed that, the optimum condition for rag pulping was; 8% active alkali and 120 minutes. At this pulping conditions, the pulping yield and mechanical and optical properties of pulp were measured as yield; 86.46 %, tear index; 20.12 mN.m2/g, burst index; 2.09 kPa.m2/g, breaking length; 1.96 km, brightness; 95.86 % and opacity: 96.39
Amir Nourbakhsh
Abstract
To improve the mechanical properties of wood plastics composites, four lignocellulosic materials (bagasse, rice straw, wheat straw and poplar wood powder) was used as the reinforcing material. The amount of nano-clay at different levels (0, 3 and 6%) were examined on the performance of wood plastic composites. ...
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To improve the mechanical properties of wood plastics composites, four lignocellulosic materials (bagasse, rice straw, wheat straw and poplar wood powder) was used as the reinforcing material. The amount of nano-clay at different levels (0, 3 and 6%) were examined on the performance of wood plastic composites. Tensile, flexural and impact properties were measured in accordance with ASTM standard test methods. Scanning electron microscope imaging (SEM) and transmission electron microscope imaging (TEM) were performed to interpret the results. The applocation of bagasse and poplar wood powder compared with wheat and rice straws increased the strength of wood plastics composites. Using 3% nanoclay particles increased the strength properties to the maximum values. Imaging the morphology of nanoclay by X-ray diffraction and electron microscopy showed the distribution of nanoclay particles in polymer structure. With increasing the amount of nanoclay to 3%, the distance between layers increased.
Sabah Ashrafi birghani; Ahmadreza Sraeyan
Abstract
The purpose of this study was to compare the effects of various concentrations of sodium hydroxide and treatment times on the properties of bagasse and Eastern cottonwood (Populus deltoids) cold soda pulp and paper. The cold soda pulp was prepared using various concentrations of sodium hydroxide (5, ...
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The purpose of this study was to compare the effects of various concentrations of sodium hydroxide and treatment times on the properties of bagasse and Eastern cottonwood (Populus deltoids) cold soda pulp and paper. The cold soda pulp was prepared using various concentrations of sodium hydroxide (5, 10, 15% based on oven dry weight), different treatment times (20, 40, 60 min.), and constant liquor to wood ratio of 10:1 at 25 ºC and atmospheric pressure. The pulp prepared after 40 min treatment time was selected and refined to the freeness of 400 ml CSF. Analysis of the properties of hand sheets was conducted based on completely randomized design. Duncan multiple range grouping test was used to classify the properties of papers. The results indicated that, the yield of pulp obtained from Eastern cottonwoodand bagasse pulp varied between 86.54% to 94.52% and 70.65 to 87.32% respectively. The absorbed alkali was varied from 2.15% to 4.78 % for Eastern cottonwood and 3.06% to 6.80% for bagasse. Eastern cottonwood had the highest yield, thickness and strength properties whereas the highest absorbed alkali and paper density were observed in bagasse. It was observed that as the concentration of sodium hydroxide was increased from 5% to 15%, the yield of pulp and the thickness of paper decreased, while the absorbed alkali, density and the strength properties of paper increased. In general, the cold soda pulp from Eastern cottonwood provided higher quality compared with bagasse under the same pulping conditions.
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.
