Automated Gate Rejection Algorithms for Real Time Recycled Fiber Blend Variations
Real-time NIR spectroscopy coupled with automated divert gate algorithms stabilizes furnish quality, rejecting off-spec recycled stock before pulper entry.
Wet End Chemical Demand
Chemical Demand
Aqueous fluid loading represents the total quantity of dissolved and colloidal substances dissolved in the liquid phase of a papermaking suspension before sheet formation occurs. Cationic demand monitors the specific ionic surplus requiring neutralization by additives during the approach flow stage of board manufacturing. Uncompensated anionic trash consumes functional polymers prematurely, which destabilizes retention aids and ruins drainage rates on the wire.
Paper machine operators gauge this variable through colloid titration to dose coagulants correctly. Excessive dissolved organic matter degrades final folding carton strength by interfering with inter-fiber bonding during pressing.
Polymers Dosage
Cationic coagulants neutralize negatively charged wood extracts and dissolved lignin originating from mechanical pulping lines. Poly Dadmac additions stabilize colloidal suspensions before fine paper stocks reach the headbox slice. Overdosing cationic polyelectrolytes induces charge reversal, creating a brittle sheet matrix that shatters during converting operations.
Residual colloidal particles escape capture when retention aids fail, leading to heavy deposits on press rolls and dryer cylinders. Starch retention improves dramatically once the ionic load of the stock drops below milligrams per litre thresholds.
Drainage Efficiency
Water removal rates across the fourdrinier table depend directly on the absence of interfering substances blocking filtration channels. High dissolved solids viscosity slows down free water release, forcing slower machine speeds to maintain target basis weight uniformity. Vacuum boxes require higher energy inputs when poorly managed wet end chemistry causes excessive swelling of cellulose fines.
Sheet porosity varies directly with the degree of colloidal destabilization achieved prior to the forming zone. Final converting performance relies on strict control over ionic charges during the initial web consolidation phase.