Mohammad Ali Hossein; Mohammad Talaeipoor; Amir Hooman Hemmasi; behzad baziyar; Saeed Mahdavi
Abstract
The effect of applying the sequence of enzymatic treatment and refining was investigated on the properties of deinked pulp from mixed office waste paper (MOW). Refining was applied for 700 and 1500 revolutions. Enzymatic treatment was applied for 60 minutes with temperature of 60°C and 13% of consistency. ...
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The effect of applying the sequence of enzymatic treatment and refining was investigated on the properties of deinked pulp from mixed office waste paper (MOW). Refining was applied for 700 and 1500 revolutions. Enzymatic treatment was applied for 60 minutes with temperature of 60°C and 13% of consistency. Applying enzymatic treatment led to decrease in strength properties of paper and also decrease in freeness of the pulp. The refining process resulted in increase of paper properties and decrease in freeness of the pulp. By applying enzymatic treatment before refining, the freeness of pulp changed significantly so that, the freeness of the pulp was 496 and 390 for 700 and 1500 refining revolution respectively just for refining but these numbers changed to 397 and 544 for same revolutions for “enzymatic treatment + refining” sequence. In a normal condition increase of refining revolution lead to decrease in pulp freeness but that was interestingly the freeness increased for 1500 refining revolution. This means that the enzymatic treatment was effective. Generally, refining itself improved the quality parameters of pulp and paper, but applying this process after enzymatic treatment changed everything.
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
Mohtaba Goli; Majid Zabihzadeh; Saeed Mahdavi; Hassan Sadeghifar
Abstract
The objective of this study was determination of the best method of bleaching including refining and bleaching (RB) or bleaching and then refining (BR) on chemical mechanical pulp (CMP) for the production of newsprint. Wood raw material consists of mixed wood forest species was chipped and air dried ...
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The objective of this study was determination of the best method of bleaching including refining and bleaching (RB) or bleaching and then refining (BR) on chemical mechanical pulp (CMP) for the production of newsprint. Wood raw material consists of mixed wood forest species was chipped and air dried to calculate the moisture content. Wood composition percentages for CMP pulping was 40% poplar, 30% maple, 7.5% oak, 7.5% alder, 7.5% willow, and 7.5% Persimmon. In order to remove heavy metal ions of pulp, the chelating was carried out with DTPA. TCF Bleaching carried out by 3% H2O2 and 2.5% NaOH based on dry weight of pulp with initial brightness of 44.6% ISO. Pulp bleaching was done in two stages, before and after the refining by laboratory PFI mill beater. Finally, handsheets were made from the RB and BR treated pulps and the sheet properties were evaluated according to TAPPI test methods. The results showed that BR treatment increased tensile, burst, tear indices, brightness, scattering coefficient, and density, but reduced yellowing, opacity, and light absorption coefficient. The results confirmed the conventional method of CMP pulp treatment (BR) in MWPI.
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.
Jafar Ebrahimpour Kasmani; Amir mohssen Nazeri; Ahmad Samariha
Abstract
Abstract: Fiber external fibrillation is one of the refining effects in conventional refining which is accompanied with a variety with other effects such as internal fibrillation. The objective of the present study was to investigate the effect of fiber external fibrillation on paper properties. Softwood ...
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Abstract: Fiber external fibrillation is one of the refining effects in conventional refining which is accompanied with a variety with other effects such as internal fibrillation. The objective of the present study was to investigate the effect of fiber external fibrillation on paper properties. Softwood kraft pulp and poplar wood CMP pulp produced at Mazandaran Wood and Paper Industries was used. An ultra-fine friction grinder was used to generate the external fibrillation. The results showed that, increasing the fiber external fibrillation increased the density of paper sheets and lower refiner gaps decreased the light scattering coefficient. Increased fiber external fibrillation improved the tensile strength of the paper sheets by about 20% and internal bonding was increased from 33% to 46% compared with unrefined fibers.
Mohammad amin Andalibian; Saeid Mahdavi; Hossein Kermanian; Omid Ramezani
Abstract
The possibility to improve the test liner board properties using mechanical treatments (refining) was studied. Old Corrugated Container (OCC) fibers used in a recycled paper manufacturing company were quantitatively and qualitatively analyzed and hardwood and softwood fibers content were estimated as ...
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The possibility to improve the test liner board properties using mechanical treatments (refining) was studied. Old Corrugated Container (OCC) fibers used in a recycled paper manufacturing company were quantitatively and qualitatively analyzed and hardwood and softwood fibers content were estimated as 22.6% and 60%, respectively. The mechanical treatment of pulp fiber was performed in a Valley Beater until the target freeness of 400 ml CSF. Then hand sheets with the basis weight of 127 g/m2 were made and the apparent density, Gurley air resistance, burst strength, folding endurance, Elmendorf tear strength, tensile strength and RCT were measured according to TAPPI standards. The results showed that all the properties of the refined sample increased compared to the control sample. Comparing the strength properties of the paper produced from refined pulp with the relevant values in Iranian national standards indicated the 33%, 50%, 117% increase in burst index, tensile index, and tear index, respectively. The refined pulp RCT strength increased by 28% compared to that of control sample. As the results indicated, test liner boards with suitable strength can be manufactured locally and even exported.
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
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
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.
