Case Studies

Pulp & Paper

Case Studies:

U.S paperboard and Kraft specialties mill saves more $2,000,000/yr using DuBois fabric cleaning solution

Opportunity

A mill producing brown paper grades, principally corrugated medium, was experiencing severe felt deposits with a competitive cleaning program. The competitive program was unsuccessful at removing both felt surface deposits and organic soils from the internal void-volume of the felt. This resulted in weekly shutdowns for downtime batch washing that still produced poor results.

The furnish consisted of OCC and NSSC stocks and the primary felt soils were identified as paraffin wax and wood pitch compounds.

The DuBois Solution

After conducting a press section survey, felt analyses and felt permeability studies, DuBois implemented new strategies for press felt cleaning.

Because of the pronounced tendency for quick felt filling and nature of the soils, DuBois’ Div-O-Kleen press felt cleaning chemical was selected. The product was applied using a DuBois supplied system that generates high temperature and high pressure water. The cleaning solution was applied at less than 0.5% concentration multiple times per day. Additionally, the program allowed for optimizing the amount of chemical cleaning each day for each felt position depending on the soil load.

To better remove dryer deposits, DuBois’ Saf-T-Brite HS product was selected. This product is, an alkaline cleaner, but contains no free caustic. The same high pressure/temperature cleaning system was used.

Results and Benefits

The overall program yielded the following impressive results:

• Total productivity gains yielded a net ROI of over $2,000,000/year, more than 2,000% ROI.
• Unscheduled downtime for press felt cleaning was eliminated.
• Sheet breaks were reduced by 22%.
• Machine speed increased by an average of 3%.
• Felt life increased by an average of 12%.
• Overall program yielded a 5.7% increase in total production.