Zahra Ebrahimi; Hossein Kermanian; Omid Ramazani; Majid Zabihzadeh
Abstract
This research was carried out to compare the paper properties from rice straw applying sodium and potassium based Chemimechanical pulping processes. Cooking conditions in potassium based pulping were adjusted as; potassium sulfite 6, 8, 10 and 12%, potassium hydroxide 3, 4, 5, 6, 8 and 12% on oven dry ...
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This research was carried out to compare the paper properties from rice straw applying sodium and potassium based Chemimechanical pulping processes. Cooking conditions in potassium based pulping were adjusted as; potassium sulfite 6, 8, 10 and 12%, potassium hydroxide 3, 4, 5, 6, 8 and 12% on oven dry weight of rice straw, impregnation time; 30 minutes, liquid to rice straw ratio of 7:1, cooking time 30 and 60 minutes and cooking temperature 130, 150, 160, 165 and 170 oC. In sodium- based pulping, cooking conditions were selected as; sodium sulfite 6 and 8%, sodium hydroxide 3 and 4 % on oven dry weight of rice straw, impregnation time 30 minutes, liquid to rice straw ratio of 7:1, cooking time 30 minutes and cooking temperature 130 and 150 oC. The selected treatment in potassium based pulping showed the average total yield of 65.19 and reject of 4.22% and in sodium based pulping showed the average total yield of 69.75 and reject percent of 3.68. After refining the selected pulp to reach the freeness of 300±25 ml CSF, 60 g/m2 hand sheets were made and physical, mechanical and optical properties were measured. Results showed that the tensile strength index, breaking length and apparent density of paper made from potassium based process was similar to paper made from sodium based process. The papers made from potassium based process had higher burst strength index and brightness compared to sodium based process and papers made from sodium based process had higher tear index and higher K/S values than potassium based paper.
Negin Nikbin; Saeid Mahdavi; Hossein Kermanian; Omid Ramezani; Amir Mohssen Nazeri
Abstract
Native starch has relatively suitable characteristics including biodegradable properties, being widely used as an adhesive in the corrugated carton manufacturing companies. Corn starch is currently used in the companies for producing adhesives. In this study, fines of NSSC pulp as natural additive and ...
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Native starch has relatively suitable characteristics including biodegradable properties, being widely used as an adhesive in the corrugated carton manufacturing companies. Corn starch is currently used in the companies for producing adhesives. In this study, fines of NSSC pulp as natural additive and ammonium persulfate as chemical oxidative additive were used to improve the adhesion properties of corn starch. Fine was added at three levels of 5%, 10%, and 15% (based on oven-dry weight of starch) and ammonium persulfate similarly was mixed at 5 levels of 0.1, 0.2, 0.3, 0.4 and 0.5 grams. Addition of fine was lead to increasing adhesion strength (PAT) of the corrugating board to the amount of 25%, 35% and 43% respectively. This improvement could be due to increasing the number and strength of hydrogen bonding of fiber layers (corrugating and liner paper) and value of solid content. Addition of ammonium persulfate revealed that the method applied similar to mixing fine had no desirable results and the other methods should be used.
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.
