Clearwater Orders Valmet Pulp Cooking System for Lewiston Tissue Mill

Valmet, Finland, will deliver key technology to Clearwater Paper's Lewiston, Idaho, USA, mill upgrade project. Valmet's delivery includes a CompactCooking G2 pulp cooking system, a new plant for generating polysulfide, and a minor upgrade of the existing bleach plant. The Lewiston mill produces tissue, paper towels, and paperboards.

Construction of the upgrade project is planned to begin this month and is expected to be completed in September 2017. The value of the order was not disclosed.  

This delivery is part of Clearwater Paper's $160 million project to install a continuous pulp digester that will replace 12 batch digesters. Benefits from the project include significant reduction in air emissions, improved pulp quality, increased production, and a more efficient utilization of wood chips.

"The efficient utilization of raw material is a vital part from a sustainability perspective. We decided to base our new cooking process on polysulfide to optimize yield. The concept and process included in the CompactCooking system from Valmet was a perfect match to our targets," says John Deuser, project manager in Lewiston. 

"This is our second new cooking system project in North America in recent times, and confirms the capabilities of our CompactCooking G2 process. We are proud to be given the trust and opportunity to be the main process supplier for both the cooking plant as well as the polysulfide generation plant in this important project. We are prepared and confident that the systems will meet all expectations of this project," said Mona Henderson, business manager at Valmet. 

The cooking plant is the first stage in a chemical pulping line where lignin is chemically separated from the fiber. CompactCooking G2 is Valmet's two-vessel continuous cooking system mainly consisting of an impregnation system and a digester for cooking of chips. It is characterized by its simple, yet sophisticated design, a flexible system that is easy to operate. 

Valmet's ImpBin impregnation technology with its unique features enables higher kappa level operation with low reject content. Using a two-vessel design ensures well defined impregnation as well as cooking zones. Effective impregnation in combination with the benefits of the CompactCooking process produce pulps with high yield and excellent pulp quality.

Clearwater Paper produces quality consumer tissue, away-from-home tissue, parent roll tissue, bleached paperboard, and pulp at manufacturing facilities across the nation. The company is a premier supplier of private label tissue to major retailers and wholesale distributors, including grocery, drug, mass merchants, and discount stores. In addition, the company produces bleached paperboard used by quality-conscious printers and packaging converters.