The effect of washing temperature, washing stages and the cooking operation on the ethanol pulp had been investigated, and the reason for higher kappa number of the ethanol pulp was discussed. The results preliminaril...The effect of washing temperature, washing stages and the cooking operation on the ethanol pulp had been investigated, and the reason for higher kappa number of the ethanol pulp was discussed. The results preliminarily showed that the dissolved lignin could re-adsorb to fiber surface by means of fiber classification technology and explained the questions found during the study. Some measures were taken to reduce the kappa number, the results had shown that there was obvious absorption in the ethanol pulping; lignin remained in the pulp could easily be dissolved and the pulp with lower kappa number could be obtained at a higher temperature; the kappa number could reduce by increasing washing time; it could enable dissolved lignin to separate out from the ethanol pulp and restrain the lignin absorption by blowing cooking liquid at high temperature.展开更多
The quality of the resulting pulping continuous digesters is monitored by measuring the Kappa number, which is a reference of residual lignin. The control of the kappa number is carried out mainly in the top of the di...The quality of the resulting pulping continuous digesters is monitored by measuring the Kappa number, which is a reference of residual lignin. The control of the kappa number is carried out mainly in the top of the digester, therefore it is important to get some indication of this analysis beforehand. In this context, the aim of this work was to obtain a prediction model of the kappa number in advance to the laboratory results. This paper proposes a new approach using the Box & Jenkins methodology to develop a dynamic model for predicting the kappa number from a Kamyr continuous digester from an eucalyptus Kraft pulp mill in Brazil. With a database of 1500 observations over a period of 30 days of operation, some ARMA models were studied, leading to the choice of ARMA (1, 2) as the best forecasting model. After fitting the model, we performed validation with a new set of data from 30 days of operation, achieving a model of 2.7% mean absolute percent error.展开更多
木材中木聚糖的侧基 4 O 甲基 D 葡萄糖醛酸在碱法蒸煮中主要转化为己烯糖醛酸侧基 (Hexenuronicacid ,简写为HuA)。不同原料、不同蒸煮程度的碱法纸浆中HuA的含量不尽相同。在测定卡伯值时HuA会消耗一定数量的高锰酸钾 ,因此HuA的存在...木材中木聚糖的侧基 4 O 甲基 D 葡萄糖醛酸在碱法蒸煮中主要转化为己烯糖醛酸侧基 (Hexenuronicacid ,简写为HuA)。不同原料、不同蒸煮程度的碱法纸浆中HuA的含量不尽相同。在测定卡伯值时HuA会消耗一定数量的高锰酸钾 ,因此HuA的存在对卡伯值有贡献。该文利用UV光谱对HuA的含量进行了测定。展开更多
文摘The effect of washing temperature, washing stages and the cooking operation on the ethanol pulp had been investigated, and the reason for higher kappa number of the ethanol pulp was discussed. The results preliminarily showed that the dissolved lignin could re-adsorb to fiber surface by means of fiber classification technology and explained the questions found during the study. Some measures were taken to reduce the kappa number, the results had shown that there was obvious absorption in the ethanol pulping; lignin remained in the pulp could easily be dissolved and the pulp with lower kappa number could be obtained at a higher temperature; the kappa number could reduce by increasing washing time; it could enable dissolved lignin to separate out from the ethanol pulp and restrain the lignin absorption by blowing cooking liquid at high temperature.
文摘The quality of the resulting pulping continuous digesters is monitored by measuring the Kappa number, which is a reference of residual lignin. The control of the kappa number is carried out mainly in the top of the digester, therefore it is important to get some indication of this analysis beforehand. In this context, the aim of this work was to obtain a prediction model of the kappa number in advance to the laboratory results. This paper proposes a new approach using the Box & Jenkins methodology to develop a dynamic model for predicting the kappa number from a Kamyr continuous digester from an eucalyptus Kraft pulp mill in Brazil. With a database of 1500 observations over a period of 30 days of operation, some ARMA models were studied, leading to the choice of ARMA (1, 2) as the best forecasting model. After fitting the model, we performed validation with a new set of data from 30 days of operation, achieving a model of 2.7% mean absolute percent error.
文摘木材中木聚糖的侧基 4 O 甲基 D 葡萄糖醛酸在碱法蒸煮中主要转化为己烯糖醛酸侧基 (Hexenuronicacid ,简写为HuA)。不同原料、不同蒸煮程度的碱法纸浆中HuA的含量不尽相同。在测定卡伯值时HuA会消耗一定数量的高锰酸钾 ,因此HuA的存在对卡伯值有贡献。该文利用UV光谱对HuA的含量进行了测定。