PULP PRODUCTION Optimal, cost-effective and environmentally friendly products for pulp bleaching and deposit control
Imerys mineral solutions are your perfect allies for pulp bleaching and deposit control, helping you save money, reduce chemical consumption, increase fiber strength and minimize effluents.
Pulp bleaching is a necessary process for the production of both graphic paper and some packaging board grades. Imerys mineral solutions such as our EcoBright™ product provide an optimal source of alkali in pulp bleaching, helping to save costs, reduce chemical consumption, reduce deposits, increase fiber strength and minimize effluents.
EcoBright™ is a stabilized magnesium hydroxide solution that is not only environmentally friendly, but delivers cost savings through:
- Elimination of magnesium sulfate
- Significant reduction of caustic soda
- Reductions of silicate and/or hydrogen peroxide
Using EcoBright™ in pulp bleaching can result in quality benefits including:
- Higher brightness values and improved pulp dewatering
- Process benefits such as higher yield, reduced oxalate deposits and less carryover to the paper machine
- Environmental benefits like cleaner water circuits and lower COD/BOD in effluents from the bleaching process
EcoBright™ reduces pulp mill downtime and process equipment maintenance which has a positive impact on overall productivity.
Pulp cleanliness is critical for runnability in both pulp and paper production. The raw material leaving the pulping process must be as free of deposits and dirt spots as possible. Imerys offers bespoke talc and bentonite based Total Deposit Control (TDC) solutions for improving the quality of all types of paper pulp, the productivity of paper production processes and the quality of final paper products.
In virgin pulp production, the main cause of runnability problems is wood pitch, a natural organic component composed of fatty acids and resin acid which is generally tacky and forms deposits in screens, filters, pipes, wires and felts leading to bad dewatering and quality issues.
In recycled fiber (RCF) and de-inked (DIP) pulp production, the main cause of runnability problems are 'stickies' such as adhesives, inks, plastics, binders and hotmelts, which form deposits in screens, filters, pipes, fabrics and dryer cylinders causing bad dewatering, holes in the finished paper and leading to excessive broke and even web breaks at the paper mill. Stickies problems result in reduced runnability and in lower total machine efficiency which directly impacts earnings.
At the paper mill, pulp which isn't completely deposit free agglomerates in fabrics and dryer cylinders causing holes in the finished paper and even web breaks.
At both stages of the papermaking process, pitch problems result in reduced quality and lower total machine efficiency which directly impacts earnings.
Environment friendly solutions
Imerys' talc and bentonite based Total Deposit Control bespoke solutions are environmentally friendly substitutes to chemical pitch and stickies control agents which improve productivity and the finished product and enable mills to work with closed water circuits - reducing river pollution and water consumption.
The optimal flocculation behavior and high adsorption capacity of our solutions also improve fiber and filler retention and optimize dewatering behavior during sheet forming.
Our cationic grades significantly reduce anionic charge in the system helping to reduce use of more expensive and less ecofriendly cationic polymers. They are particularly effective in pulps containing high levels of anionic trash.
TDC can bring huge benefits
It keeps the pulp and paper production process streams clean and increases mill productivity:
- Improving pulp quality
- Preventing deposits in the equipment
- Increasing machine runnability and reducing downtime
- Reducing felt cleaning and leading to fewer felt changes
- Improving sludge dewatering and drainage time
- Allowing you to work with closed water circuits, reducing water consumption and river pollution
It improves the quality of the finished paper, reducing dirt count and surface defects of finished paper.
Our Total Deposit Control solutions are ideal for:
- Virgin pulp
- RCF and DIP
- Newsprint paper production where they promote optimum runnability
- Tissue paper production where they minimize ash. We particularly recommend our cationized Mistron® product range for tissue paper pulp which will limit ash content increase, without significantly impacting essential tissue paper properties.
- Solid board production where they improve the quality and printability of the finished product and enhance fines and filler retention in wet end processing.
We recommend our Mistron® and cationic Mistron® K talcs and Aquamont® bentonite grades for deposit control.
Wet end treatment
Due to its enormous surface and high cation exchange capacity, bentonite forms a highly effective adsorbent and flocculation agent during wet-end processing.
We recommend our Altonit® grades for retention and dewatering during wet-end processing.
Water loop treatment
With its high adsorption capacity, bentonite is an excellent solution for the treatment and purification of process water, wastewater and effluents in de-inked pulp (DIP) paper production using dissolved air flotation (DAF) and micro-flotation techniques.
We recommend our Aquamont® grades for water loop treatment.
We offer a full range of bespoke formulation and technical and process support services to help you match the right mineral grade to your application requirement.