Study On APMP Properties And Its Process Of Two Kind Of Eucalyptus

Wood fibres have much superiority in pulping process and waste liquor recovery, conforming to the requirements of high quality paper. In our country, the unreasonable raw material structure and the lower wood pulp proportion became a bottle neck of paper industrial development in our country. It have been more than one hundred years since our country introduced Eucalyptus. Eucalyptus plantation had 1,540,000 ha . The varieties of eucalyptus are about 900 . In view of these Eucalyptus different pulping perfor-mance, we must analyze and research using different method.In this paper, the fiber morphology, chemical component and wood density were discussed above all. After selecting two priority sample, we processed APMP, adopting orthogonal test. Putting these results into range analysis, variance analysis and regression analysis using NOSA statistical software, we set up a regression equation about breaking length and whiteness with chemical pretreatment conditions for ultimately choosing relatively pulping chemical pretreatment condition.In these tests, we found that these sample's fibre length is longer than others, such as E.urophylla and E.globules, but E.urophyllct ×camaldulensis 's is relatively shorter. Their holocellulose content is higher, lignin content is also higher, extraction comparison is relatively less.Under the laboratory condition, the optimized chemical pretreatment condition of E. urophylla×grandis APMP is:In first chemical pretreatment, dosage of NaOH is 5.5%, dosage of H₂O₂ is 1%, dosage of Na₂SiO₃ is 1%, dosage of MgSO₄ is 0.5%, dosage of EDTA is 0.3%, temperature is 75℃, time is 45min, ratio of cooking liquid to fibre weight on oven dry wood is 1:4; In second chemical Pretreatment, dosage of NaOH is 2.5 %, dosage of H₂O₂ is 5 %, dosage of Na₂SiO₃ is 3%, dosage of MgSO₄ is 0.5%, dosage of EDTA is 0.3%, temperature is 75 ℃, time is 45min, ratio of cooking liquid to fibre weight on oven dry wood is 1:5. The breaking length of E.urophylla.×grandis APMP reach 3.4km, whiteness is 66° ISO, which fundamentally meet the require of common newsprint and produce some blending pulp with other pulp to substitute for long stock.The pulp performance of E.cloeziana is not good, therefore it's unfit to APMP.At last some suggestions for the future studies were given: we should develop the Eucalyptus APMP performance and generalizing their commercial utilization in pulpingtechnology, equipment management and process control.