Detection and Prevention of Spoilage in Additives

摘要

Papermakers often fail to recognize the economic losses caused by microbes in the coating kitchen and additives area of the mill. Bacteria and fungi readily colonize starch, protein, dyes, polymers, carbonates, clays and other additives. For example, even dry starch contains bacterial endospores that easily survive the hot temperatures of a jet cooker. Untreated slurry starch contains tens of millions of actively growing bacteria per mL. Spoiled starch will not give optimum performance as either a strength additive or as a binder for coating formulations. This paper will discuss how to recognize signs of spoilage in different types of additives, how to minimize spoilage through proper housekeeping practices and intelligent application of preservatives.