Pulp and paper
Ahmad Samariha; Jafar Ebrahim poor tasmani; Alireza Khakifiroz
Abstract
This research was performed to investigate the properties of CMP pulp from rape straw. Samples of Colza straw was prepared from a farm located in the vicinity of Babul. Chemo mechanical Pulping process was employed using the 20 % cooking liquor of Mazandaran pulp and paper mill (Sodium Sulphite) based ...
Read More
This research was performed to investigate the properties of CMP pulp from rape straw. Samples of Colza straw was prepared from a farm located in the vicinity of Babul. Chemo mechanical Pulping process was employed using the 20 % cooking liquor of Mazandaran pulp and paper mill (Sodium Sulphite) based on the dry weight of colza straw. Cooking time and temperature were adjusted at 30, 40 and 50 minute and 170 degree centigrade, respectively. Pulps were refined up to 300± 25 CSF by using PFI Mill refiner and 60 g/m2 hand sheets were made from each sample of pulps. The strength indices of hand sheets were measured using TAPPI standards. The results showed that strength indices like Tensile strength, Tear strength, Burst strength, Breaking length and Stiffness increased as the pulp yield decreased.
Pulp and paper
Alireza Khakifiroz; Seeyed Ahmad Mirshokraie; Amir homman Hamasi; Hababalah Khadmieslam; Mohammad Talaei poor
Abstract
Permanent or durable paper is a kind of paper that has a high degree of permanence and is likely to retain the properties which influence readability and document handling when storing in a protected environment for a long period. Permanence depends mainly on the chemical stability of the paper itself. ...
Read More
Permanent or durable paper is a kind of paper that has a high degree of permanence and is likely to retain the properties which influence readability and document handling when storing in a protected environment for a long period. Permanence depends mainly on the chemical stability of the paper itself. Stability may be impaired by chemical reactions involving the paper's own components and by reactive agents from the environment and human being i.e., from air or filing enclosures. Poor chemical stability produces a chain reaction which in long term storage has a pronounced adverse effect on the mechanical or optical properties of the document. The main reactions causing mechanical deterioration are acid hydrolysis and oxidation. Yellowing is due to photochemical and thermal processes. Whatever the fibers used to make paper are longer , alkaline paper making is used , cationic elements such as Fe+2, Fe+3, Cu+2, Mn+2 and kappa number of pulp are minor, it is expected that the paper made is more permanent .In this research imported bleached Eucalyptus kraft pulp was used. The used pulp was refined according to tappi test method T248 cm-85 with PFI mill to reach freeness (300±25) CSF at number of beating revolutions 12000 .Hand sheets were made according to SCAN C25-65 standard with grammage 70.AKD sizing were used 2% oven dry weight of pulp and EDTA as chelating agent was used in concentrations 0 , 0.25 , 0.5 , 0.75 percent. For more assurance deionized water was used. furthermore, 20% calcium carbonate was used as residual alkaline and filler. Then hand sheets were laid under U.V radiation with wavelengths between 330 to 440 nm in 0,10, 20, 30, 40 and 50 hours interval and were conditioned in controlled temperature and relative humidity . pH of Extractive solutions were adjusted between 7 to 7.5 . At last, each strength indices were measured with three measurement frequencies and to compare the amount of mean strengths of produced handsheets, variation analysis (ANOVA) and Duncan test were used with SPSS software and the charts were drawn with Excel software.
Pulp and paper
Mohammadreza Dehghani Firouzabadi; Afshin Tvasoli; Saeed Mahdavi
Abstract
We studied the possibility of replacing imported long fiber pulp (ILFP) with kenaf bast fiber soda pulp (KBFSP) to improve the quality of paper made with bagasse soda pulp (BSP). To do so, we produced BSP with kappa number 13.5 similar to that prepared by Pars Paper Mill. We also produced KBFSP with ...
Read More
We studied the possibility of replacing imported long fiber pulp (ILFP) with kenaf bast fiber soda pulp (KBFSP) to improve the quality of paper made with bagasse soda pulp (BSP). To do so, we produced BSP with kappa number 13.5 similar to that prepared by Pars Paper Mill. We also produced KBFSP with kappa number 21.6 similar to the unbleached imported ILFP. The yield percent for BSP and KBFSP were respectively 48.9 and 55.6 %. The maximum pulping temperature was 165 °C; alkaline was 20% based on sodium hydroxide and ratio of liquor to dry weight of the raw material was 8:1. All the three pulps were beaten up to a freeness degree of 400 ml, CSF. Amounts of 0, 10, 20 and 30 percent ILFP and KBFSP were mixed with 100, 90, 80 and 70 percent BSP to produce hand sheets. In all cases of KBFSP mixing with BSP, the thickness of the generated hand sheets were higher than those produced through mixing ILFP with BSP while the density was lower. The difference in burst strength and breaking length of a mixture of 30% KBFSP with 70% BSP in the hand sheets were non-significant as compared with those of ILFP and BSP. Tear strength and opacity of mixing 30% KBFSP with 70% BSP were significantly higher than those of the ILFP and BSP with the same mixing ratio. We suggest that KBFSP provides a suitable replacement for ILFP to improve physical and strength properties of paper made with BSP.
Pulp and paper
Saeed Mahdavi; masoudreza habibi; kermanian hossein
Abstract
Global concerns for preservation of forests and elimination of pollution from pulping and papermaking processes has led us to explore alternate fibrous resources other than wood and new environmentally begin pulping and bleaching processes for papermaking without sacrificing quality. Various alternate ...
Read More
Global concerns for preservation of forests and elimination of pollution from pulping and papermaking processes has led us to explore alternate fibrous resources other than wood and new environmentally begin pulping and bleaching processes for papermaking without sacrificing quality. Various alternate fibrous resources such as agricultural residues are already in use in many countries and considerable research have been undertaken to produce pulps by conventional and non-conventional processes. Wheat straw has high quantity among agricultural residues in Iran. Kraft, Soda and Ethanol-alkali pulping were carried out after sampling and preparing of wheat straw. Retention of carbohydrates is improved compared to the alkaline pulping processes, resulting in about 8 to 15 % higher yield at the same level of residual lignin. There was lower energy consumption for refining Ethanol-alkali pulps. There were no statistical differences among the physical properties. The strengths of Ethanol-alkali pulps consist of tear index, burst index and breaking length were lower than alkaline pulps, but all of the strength properties were higher than kraft and liner paper except tear index that addition of some long fiber can solve the problem.
