Lime is traditionally used to reconstitute caustic soda from the sodium carbonate left over from the pulp-making process.
Quick lime is usually mixed with water to form a slurry to which carbon dioxide is added. The resulting reaction produces a very fine precipitated calcium carbonate (CaCO3). This filler is used in paper production to enhance the paper's whiteness, opacity and texture. Lime is also used as a reagent to soften process water in paper factories.