Research Initiation: Kinetic Study of Kraft Delignificationby On-Line Sampling and Analysis

这项工作是对硫酸盐脱木素反应的基础性研究，目的是确定可用于跟踪反应进程的关键可测量反应参数。白酒分析系统将用于监测一系列全面的白酒特征。活性化学物质的消耗将通过现场监测液体的电导率和提取液体样品的离子色谱来测量。溶解木质素的数量将通过吸光度进行监测。采用凝胶渗透色谱技术测定木质素的相对分子质量分布。循环液中的总溶解固体将用折射率检测器来测量。基于这些测得的白酒特性，将建立动力学模型。这一结果将有助于开发基于可测量白酒特性的控制系统。这样的控制系统将通过以更高的得率产生均匀质量的纸浆来提高制浆操作的生产率，并改善制浆操作的整体经济性。纸浆和造纸业是美国第三大工业。即使是收益率的小幅增长也会产生巨大的美元影响。这项工作可以加强对木片消化器的控制，从而获得更均匀的纸浆，更高的产品质量和更高的产率。

This work is a fundamental study of the Kraft delignification reaction with the goal of identifying the key measurable reaction parameters that can be used for following the progress of reaction. A liquor- analysis system will be used to monitor a comprehensive array of liquor characteristics. Depletion of active chemicals will be measured by monitoring in-situ the conductivity of the liquor and by ion chromatography of the extracted liquor samples. The quantity of dissolved lignin will be monitored by absorbance. Gel permeation chromatography will be used to measure the molecular weight distribution of lignin. The total dissolved solids in the circulating liquor will be measured by using a refractive index detector. A kinetic model based on these measured liquor characteristics will be developed. The result will help develop a control system based on measurable liquor property. Such a control system will result in increased productivity of the pulping operation by producing a uniform quality of pulp at a higher yield and improve the overall economics of the pulping operation. The pulp and paper industry is the third largest industry in the United States. Even small increases in yield would have a large dollar impact. This work could lead to the enhanced control of the wood chip digester thus resulting in a more uniform pulp, higher product quality, and higher yield.