Anionic Trash is referred to as negatively charged colloidal and dissolved polymeric materials in paper furnish, usually coming from the wood. With the increasing use of secondary fibers and with whitewater recirculating systems being in tighter chambers, high amounts of dissolved and colloidal substances (DCSs) are often accumulated in papermaking systems. DCSs, which in most cases are highly negative and are thus also called anionic trash, severely affect the effectiveness of many cationic chemical additives, including cationic dry strength agents (DSAs).
It is generally reasonable to recommend using Anionic Trash Neutralizer/ Anionic Trash Catcher (ATC) before using a cationic dry strength agent such as cationic starch or cationic polyacrylamide. Ideally, the ATC at its proper dosage neutralizes all the anionic trash while the negativity of the fiber is not affected, so that the fiber can take as much of the subsequently added cationic chemicals to ensure their effectiveness.
Anionic Trash Neutralizer/ Anionic Trash Catcher (ATC)