In kraft pulp digester, lignin in wood chips is removed through delignification by hydroxide and sodium sulfide solution. Since both macroscopic and microscopic properties of wood pulp significantly affect the attributes of paper products, several multiscale modeling frameworks have been developed. However, these models did not consider fiber-to-fiber (F2F) heterogeneity; it is an important challenge these days as the fibers are provided from multiple sources to meet the increasing demand. Therefore, we developed a multiscale modeling framework to describe the evolution of heterogeneous fibers in a digester by running multiple kinetic Monte Carlo simulations in parallel. Specifically, the F2F heterogeneity is incorporated by introducing variation in heat capacity and dissolution rate for each fiber. Based on the developed multiscale model, we also designed an offset-free model predictive control system to regulate the cell wall thickness distribution of fibers as well as Kappa number in a pulping process.

在牛皮纸浆蒸煮器中，木片中的木质素通过氢氧化物和硫化钠溶液的脱木素作用被去除。由于木浆的宏观和微观性质都显着影响纸制品的属性，因此已经开发了几种多尺度建模框架。但是，这些模型没有考虑光纤到光纤（F2F）的异质性。如今，这是一个重要的挑战，因为要从多种来源提供纤维来满足不断增长的需求。因此，我们开发了一个多尺度建模框架，通过并行运行多个动力学蒙特卡洛模拟来描述蒸煮器中异质纤维的演变。具体而言，通过引入每根纤维的热容量和溶解速率的变化来引入F2F异质性。基于开发的多尺度模型，