Performance of enzymatically deinked recovered paper on paper machine runnability

Abstract

The process of enzymatic deinking has been proven to be an effective method for removing noncontact inks from recovered paper. A secondary effect of enzyme treatment is enhanced pulp drainage. This study investigated the effects of enzymatic deinking on paper machin runnability, specifically drainage and wet-web strength enhancement. three deinking trials were conducted on industrial-scale equipment. Two trials used the enzymatic deinking method developed at the Forest Products Laboratory, and one trial was a surfactant control. Pulp produced in each of the three tirals was used in a pilot paper machine run. During each run, overall runnability, drainage, pressing response, and wet-web strength were evaluated. In general, the enzyme-treated pulp ran better than the control pulp. Mainly, it was the enhanced drainage and wet-web strength that contributed to the improvement in runnability. Application: Practical implications due to enhanced drainage and wet-web strength for the papermaker include (a) better sheet formation if a lower headbox consistency is used and (b) greater-production rates or reduced drying energy use if headbox consistencies are maintained.