Wet end additives and chemicals contribute to paper-making by providing functional properties and serving as the most important process aid of the entire production. Additive utilization in papermaking depends on the type of paper or board, other raw materials used, papermaking technology and desired end properties. The global paper and board industry uses billions of tons of different additives annually. If the dosage location is in a long distance to the head-box, it generates some significant disadvantages: The long delay time keeps the chemical extended time together with stock components; it collides across ran-domly with disturbing colloidal material, entrained gas bubbles and liquids. Reactions may be partly eligible with targeted results, but partly reactions are generated randomly, uncontrolled and by accident, resulting to unwanted effects. Several circulating loops of the PM short circulation process will keep part of chemicals in circulation for longer periods thus extending the time with the expiained effects.
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