In a continuous digester, wood chips and liquor are continuously fed to, and withdrawn from, a pressure vessel. Continuous cooking offers some distinct advantages over batch cooking, including reduced space requirements, improved cooking control, and improved energy efficiency. Many variations of continuous digester equipment and process conditions have been used. Some digesters are hydraulically filled, while others utilize a vapor phase. This module covers the basic principles of operation of hydraulically filled continuous digesters.
Learning Objectives
At the end of this module, you will be able to:
- Describe some of the advantages of continuous cooking
- Identify the purposes of a continuous digester chip feed system
- Describe how process zones are established in a continuous digester
- Describe the advantages of using an impregnation vessel
- Identify some of the guidelines which maximize the benefits of continuous cooking