Xylanase and Laccase for Recycled Pulp Mills

Xylanase and Laccase Options for Recycled Pulp Mills

Recovered fiber is never a clean, fixed input. Furnish mix, print type, coating load, loop water, ash, dissolved organics, stickies, and broke quality all move through the system together. That is why non-cellulase enzyme selection has to be tied to the mill’s actual deinking line, not chosen from a generic catalog.

Pulprift supplies xylanase and laccase options for paper recycling mills that need practical control over deinking response, brightness development, drainage, deposits, and chemical demand. If you are looking for an enzyme supplier for paper deinking mills, we help narrow the enzyme path around your furnish, chemistry, equipment limits, and commercial targets.

Request a quote through the on-site form

Why Mills Compare Xylanase and Laccase in Recycled Pulp

Xylanase and laccase are used for different reasons in recycled pulp processing. Neither should be treated as a one-size-fits-all deinking answer.

Xylanase: surface opening and wash response

Xylanase acts on hemicellulose-rich regions associated with fiber surfaces. In recycled pulp applications, the operating goal is usually to make existing washing, flotation, and bleaching chemistry work more efficiently without attacking cellulose strength.

Potential mill outcomes include:

Improved ink detachment and removal support in suitable furnishes
Better brightness response from the same or reduced chemical program
Improved drainage where hemicellulose-related fines behavior is limiting throughput
More stable wet-end behavior through lower dissolved load pressure
Support for yield protection when mills want to avoid cellulase-driven fiber loss

Xylanase is often evaluated when the mill has a clear brightness ceiling, slow drainage, high chemical demand, or a need to improve process efficiency without changing the core deinking system.

Laccase: color body and contaminant oxidation support

Laccase targets oxidizable phenolic structures and selected colored contaminants. In recycled pulp mills, laccase is typically considered where color reversion, residual chromophores, certain extractives, or chemical load are part of the operating issue.

Potential mill outcomes include:

Cleaner pulp appearance in targeted furnish streams
Reduced pressure on peroxide, caustic, silicate, or reducing agents where process conditions allow
Support for lower residual color load before bleaching or final stock preparation
Assistance with selected extractive-related deposit tendencies
Better fit for mills pursuing lower chemical intensity without sacrificing sheet requirements

Laccase performance depends strongly on furnish chemistry, dissolved oxygen availability, mediator strategy where applicable, retention time, and downstream treatment sequence.

Where These Enzymes Fit in a Deinking Line

Pulprift helps mills evaluate enzyme placement around actual process constraints. Common evaluation points include:

Pulper discharge
Dump chest
High-density or medium-density storage
Pre-flotation conditioning
Washer feed or filtrate loop treatment
Thick stock storage before bleaching
Side-stream treatment where loop water is creating carryover problems

The correct location depends on the enzyme objective. A xylanase program aimed at fiber surface modification may need a different contact window than a laccase program aimed at oxidizable color bodies or extractives. We look at where the enzyme can work without disrupting pulper energy, flotation chemistry, surfactant balance, pH control, or downstream retention aids.

Selection Factors We Review Before Quoting

A quote should match the mill problem. Before recommending xylanase, laccase, or a combined trial, Pulprift reviews the process conditions that determine whether the enzyme can create measurable value.

Furnish and contaminant profile

We look at:

Office waste, mixed paper, old newspapers, old magazines, coated grades, boxboard, or broke share
Ink type and print age
Coating, filler, and ash contribution
Hot-melt, pressure-sensitive adhesive, wax, latex, and extractive load
Seasonal and supplier-driven furnish variation

Deinking and bleaching sequence

We review:

Pulper chemistry
Surfactant and collector strategy
Flotation cell performance
Washer loading
Peroxide or reducing bleach conditions
Loop closure and filtrate reuse
Final brightness and dirt count targets

Operating window

We align enzyme selection with:

pH range at the selected addition point
Process temperature
Available retention time
Stock consistency
Shear and mixing conditions
Conductivity, dissolved solids, and carryover chemicals
Downtime risk and operator handling requirements

This keeps the trial grounded in mill-floor reality. An enzyme that performs well outside the line does not matter if it cannot survive the actual process window.

What Pulprift Targets in Commercial Trials

Pulprift trials are built around outcomes that pulping managers, quality teams, and plant managers can measure against production goals.

Deinking response

We focus on whether the enzyme supports ink release, flotation removal, wash efficiency, or visible speck reduction under the mill’s existing equipment limits.

Brightness gain or chemical reduction

The target may be higher brightness at the same chemical charge, or equivalent brightness with reduced bleaching pressure. The commercial value depends on grade requirements and chemical cost structure.

Drainage and throughput

Where drainage is constrained by fines behavior, dissolved organics, or fiber surface conditions, xylanase evaluation can be tied to dewatering rate, press loading, washer capacity, or machine speed opportunity.

Stickies and deposit pressure

Laccase options may be considered where oxidizable contaminants or extractives contribute to deposit formation. We frame this around downtime, cleaning frequency, screen performance, and defect risk.

Yield and fiber quality

Pulprift’s non-cellulase focus is designed for mills that want process help without creating unnecessary cellulose damage. Yield, strength, freeness, fines profile, and sheet performance should stay visible throughout the trial.

Xylanase vs. Laccase: Practical Decision Guide

Consider xylanase when:

Brightness response is limited by fiber surface accessibility
Washing or flotation needs support without a major equipment change
Drainage is restricting throughput
The mill wants to reduce chemical pressure while protecting fiber strength
Furnish contains hemicellulose-rich fiber fractions that respond to controlled surface modification

Consider laccase when:

Residual color bodies or phenolic contaminants are part of the brightness problem
Extractives or oxidizable contaminants are contributing to deposit risk
The mill is evaluating lower chemical intensity
Loop water quality is affecting downstream appearance or stability
The process has enough contact opportunity for oxidative treatment to matter

Consider a combined evaluation when:

The mill has both brightness and drainage limitations
Furnish variation creates multiple failure modes
Chemical reduction is a target, but deinking stability cannot be compromised
The current program works, but cost, downtime, or reject load is rising

Combined does not always mean blended. In many mills, the better answer is staged treatment with each enzyme placed where it has the right process window.

Commercial Fit for Recycled Pulp Mills

Pulprift supplies enzyme options for mills producing recycled pulp for tissue, printing and writing grades, packaging, molded fiber, and specialty recovered-fiber applications. We support teams that need a defined enzyme recommendation, a practical trial plan, and quote terms that fit plant purchasing.

Typical buyer priorities include:

Lower deinking chemical cost
Higher saleable brightness
Reduced dirt and specks
Improved drainage and washer performance
Reduced deposit-related downtime
More stable operation across furnish swings
Lower reject or yield loss risk
Easier operator adoption

We do not recommend enzyme changes in isolation. The value comes from matching enzyme selection to process placement, furnish behavior, and the mill’s financial target.

Request a Quote

If your mill is comparing xylanase, laccase, or a non-cellulase enzyme program for recycled pulp, send Pulprift your operating conditions through the on-site request form.

Helpful details include:

Recovered furnish types and approximate blend
Deinking sequence and current chemical program
Current brightness, dirt, stickies, drainage, or deposit issue
Addition points available for a trial
pH, temperature, consistency, and retention window at those points
Target outcome: brightness gain, chemical reduction, drainage, downtime reduction, or yield protection
Expected monthly usage or trial volume

Request a quote through the on-site form

Pulprift will respond with a fit recommendation and commercial quote for the enzyme option most relevant to your mill conditions.

Xylanase and Laccase for Recycled Pulp Mills | Pulprift