Wood fiber accounts for more than 90% of the raw material used in the production of paper and board products, and it can come from a variety of sources. These sources can be slushed virgin fiber that is produced onsite, market pulp from other pulp mills, or recycled/secondary fiber. Recycled paper can be broken into several categories including old corrugated containers, mixed paper, and deinking grades. Most deinking grades consist of old newspapers, old magazines and office waste. This course will focus on the equipment and processes used for deinking.
Learning Objectives
- The purpose of deinking
- The role of repulping, flotation, washing, dispersing, and bleaching in deinking
- How surfactants are used for deinking
- How flotation deinking works
- The process and typical equipment for flotation deinking
- How pulp is deinked by washing
- The process and typical equipment for dispersing
- The process and typical equipment for deinked pulp bleaching
- Safety hazards and guidelines associated with recycled fiber deinking