Research Of The Technology About Poplar Chemimechanical Pulp And Its Application

Pulping and papermaking is a huge resource consumption,environment polluting industry.The rapid development of China’s paper industry put forward severe challenges to resources and the environment.Introduction of foreign advanced equipment,the high yield pulping technology,adjust the structure of raw materials,efficient use of resources and reduce the environment pollution are the main streams of the development of papermaking industry.Pan mill chemical pretreatment learn alkaline hydrogen peroxide mechanical pulp(PRC-APMP)is a high yield pulp,PRC-APMP has A lot of advantages,such as low cost,high thickness,high opacity.So the PRC-APMP has been widely used at home and abroad and the development,the PRC-APMP is used not only for white cardboard,such as quantitative cardboard copperplate papercore layer and development for offset paper,electrostatic copy paper,etc.In this paper,the cypress chemical mechanical pulp(PRC-APMP)technology are studied,this paper discusses the application of the aspen mechanism for pulp in paper making and the main results are as follows:1.Beating concentration is not relationship with dipping time,but the overall trend is with the extension of dipping time,beating degree showed a rising tren dwith the increase of the concentration of NaOH.But the water retention value and fiber length are first increased and then decreased with the concentration of NaOH increased.Water retention value and fiber length maximum appeared incondition of the concentration of NaOH is 6%,and dipping time is 24 h.2.The pretreatment condition of raw materials has a direct influence on the physical and optical properties of the paper.With the increase of the amount of alkali,the opacity gradually decreased,the thickness of the loose was first decr eased and then increased,and the compressive strength,tensile strength and bend ing strength increased first and then decreased.The optimal pretreatment conditions for NaOH concentration were 6% and the soaking time was 24 h.3.In the bleaching process,pH value cannot be maintained in low alkali condition,which is detrimental to the bleaching with high alkali content,and the optimum bleaching pH value is 10.1-11.34.Impregnation effect is not only related to the amount of chemicals,but also related to the material properties.Eucalyptus impregnated for 24 hours,there is still not dipped into the region,so it does not have the actual meaning of ind ustrial production,while the amount of hydrogen peroxide to reach 8%,the whit eness is still 73.4%,the plasma effect is far worse than poplar.5.The optimum experimental condition of poplar chemi-mechanical pulp: soda ash dosage of 5%,3% silicon layer,NaOH6%,sodium peroxide 1%,3% sodium sulfate,2% hydrogen peroxide.Eventually,it becomes pulp index for the pH value of the residual liquid for 9-10 loss rate of raw materials for screening 21.74% after good pulp ratio was 81.2% for detecting paper tensile index is 7.2627N*m/g,the whiteness of 31.4%.6.The effect of hydrogen peroxide bleaching can be improved by adding urea into the hydrogen peroxide bleaching of poplar PRC-APMP.When the dosage of urea was 1%,the brightness of bleached pulp was increased by 1.7%ISO.Compared with DTPA and urea alone,the synergistic action of urea and DTPA could further improve the effect of hydrogen peroxide bleaching.The effect of the addition of urea on the physical properties of bleached pulp is very small.7.Compared with the poplar PRC-APMP,smaller effect urea bleaching effect of poplar CTMP hydrogen peroxide.Poplar wood pulp bleaching system in transition metalion bleaching effect of Fe Mn ratio on DTPA had significant effect.Compared with the DTPA result of manganeseions inhibited the decomposition of hydrogen peroxide is invalid,resulting in DTPA of manganese ions inhibited the decomposition of hydrogen peroxide is more significant.With the increase of the proportion of Fe/Mn in the system,reducing the role of DTPA.