Concept for Gentle Removal of Impurities, 1998 Recycling Symposium Proceedings

Regardless of the product a recycled fiber mill makes from recovered paper, whether lightweight fine paper or heavy board, the first steps in stock preparation lines are very similar: pulping, trash removal, high consistency cleaning, and coarse screening.

Traditionally, recycled fiber processing utilizes four or five separate pieces of equipment to prepare the stock. This traditional method requires higher investment, operating and maintenance costs due to all the auxiliary equipment, assembly, piping, instrumentation, and electrical requirements needed to function properly.

Alternatively, there is a concept that allows recycled fiber mills to perform four different preparation stages using two complementary pieces of equipment First, the drum-type pulper gently pulps the incoming raw material and removes trash. Secondly, a specialized screen performs centrifugal cleaning and coarse screening in a single unit. Both pieces of equipment perform two functions, but they are simply not combinations of traditional equipment.

In addition to the economic, the lower energy impact of this concept permits more efficient removal of plastic particles or stickies during the very first steps of the process.