Paper

Two main functions performed by two products supplied by Calcica: regeneration of reactants with quick-lime, improving mechanical paper properties through the addition of PCC.
Paper is a combination of mechanically or chemically treated vegetable fibres. Its first production dates back to the year 100 A.D and its process has undergone many changes and advances, making it into a modern and demanding sector today.
Calcica offers tailor-made products for this sector, mainly directed at a two-step process:
To release the natural wood fibres, it is necessary to prepare a cooking process in a digester with liquid compounds and lignin separating agents. Degraded liquids in cooking are then regenerated using Calcica products.
Once separated and cleaned, the fibres are passed through paper machines, which distribute fibres, adding mineral fillers and additives to stabilize and give the paper consistency, which is obtained after the final drying.
Products that Calcica offers to the paper industry are:
 

CALCIUM OXIDE

Quick-lime is used as active ingredient in the sulphate procedure and as regenerator agent of reactives used in the Kraft process of paper production, enabling its reuse and exploitation. It is also used as bleach of paper paste, flocculant and neutralising agent in the water treatment process.
 

PRECIPITATED CALCIUM CARBONATE

Is used as a filler to increase the volume and porosity of the paper, while providing whitening levels and a significantly higher opacity to those obtained through non-synthetic fillers such as Natural Carbonate (CC.) Thanks to the above features, Calcica is specially recommended in low weight papers which need opacity.