Abas Fakhryan; Hossein Hosseinkhani; Fardad Golbabaei; Mohammad mehdi Brazandeh
Abstract
In this Investigation chemical, physical, morphology, pulp and paper making characteristics of Populus costanzo were studied. The average dry and critical specific gravity was found to be 0.39and 0.36 and the fiber morphology including fiber length , diameter ,lumen and thickness ...
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In this Investigation chemical, physical, morphology, pulp and paper making characteristics of Populus costanzo were studied. The average dry and critical specific gravity was found to be 0.39and 0.36 and the fiber morphology including fiber length , diameter ,lumen and thickness of cell wall 1.14 mm,28.84 µm, 28 µm ,and 2.92 µm was determined respectively. The average chemical composition including cellulose 50.74%, lignin 19.18%, Ext. 1.22% and Ash 1.65% were measured. In order to cook and pulping, Kraft process was used. The maximum yield and kappa number of Populus costanzo at 1 hour cooking time, 150°c cooking temperature and 12% effective alkali condition obtained at 61.91% and 54.83 respectively and the minimum yield and kappa number at 3 hour cooking time, 170°c cooking temperature and 16% effective alkali condition obtained at 45.63% and 13.42 respectively.
Pulp and paper
Mohammad Mahdi Barazandeh; Saeid Mahdavi; Abbas Fakhryan
Abstract
Because of importance and wide usage of different species of Populus wood in paper pulping, the delignification reaction in pulping process of P. deltoides was investigated in order to obtain the relation between residual lignin in the pulp and cooking time. The samples were 10 years olded of Populus ...
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Because of importance and wide usage of different species of Populus wood in paper pulping, the delignification reaction in pulping process of P. deltoides was investigated in order to obtain the relation between residual lignin in the pulp and cooking time. The samples were 10 years olded of Populus deltoids woods which were collected from Chamestan Research Station located in Noor city of Mazandaran province. Kraft method was used for pulping the condition of which were 25% sulfidity, 14% alkali, 5:1 the ratio of liquor to sample, maximum cooking temperature as 155, 165, 175 degree centigrade. Kappa number and the yields of pulps were estimated and residual lignin was calculated for each sample. Using the models predicted for rate equation and trial and error method in excell software, the order and rate constant of delignification reaction were evaluated for each cooking temperature. The results show that the rate equations of delignification reaction of Populus deltoides in temperatures of 155°C, 165°C and 175°C have the orders of 5.5, 2.5 , 1 and the rate constants of 1.8× 10-7 min.-1 conc.-4.5, 7.7× 10-4 min.-1 conc.-1.5 and 3.5× 10-3 min.-1 , respectively. Using these equations it will be possible to control the pulping process and predict the time required to obtain a desired lignin concentration in the pulp.
MOHAMMAD MAHDI BARAZANDEH; Abbas Fakhryan roghani
Abstract
Bagasse pulping process was conducted using soda liquor in five maximum cooking temperatures, 80, 100, 120, 140 and 160 degree centigrade. To evaluate rate equations of delignification reaction in each temperature, pulping was done in the same alkali and liquor to bagasse ratio but varying cooking ...
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Bagasse pulping process was conducted using soda liquor in five maximum cooking temperatures, 80, 100, 120, 140 and 160 degree centigrade. To evaluate rate equations of delignification reaction in each temperature, pulping was done in the same alkali and liquor to bagasse ratio but varying cooking times and the results were presented in the form of rate equations with respect to residual lignin concentration in the pulp. The rate equations revealed that delignification reaction rate of bagasse depends both on cooking temperature and residual lignin concentration. The order of rate equation in higher temperatures is far higher than those in low temperatures and due to this, reaction rate in high temperatures is more dependent on residual lignin concentration and far than the rate reaction in lower temperatures. With reaction progressing, the difference between the two rate reactions is reduced and after one point it will be reversed. Using experimental data, the order of delignification reaction rate in temperatures 80, 100, 120, 140 and 160ْC were obtained as 4.6, 4.6, 5.5, 22.8 and 22.7 respectively. The rate constants were also calculated as 1.3×10-5 conc.-3.6 min.-1, 1.1×10-4 conc.-3.6 min.-1, 7.2×10-5 conc.-4.5 min.-1, 6.2×10-10 conc.-21.8 min.-1, 4.0×10-11 conc.-21.7 min.-1, respectively.
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.
