Specialty Minerals (michigan) Inc.

Specialty Minerals Inc.

Joseph Andrew Sohara

David Lee Smith

Gerald Dean Erdman

Harry John Huhn, Iii

Keith Hanchett

Marko Pohjolainen

Ari Aari

David Peters

The current invention relates to methods of the recovery and re-use of minerals obtained from the combustion of the residues of a process to recycle paper.

Process for preparing a PCC composite product

A method for obtaining particulate calcium carbonate exhibiting improved brightness and color and having uniformity of size such that when the particles are formed in the causticization process in a kraft pulp mill, the time required to separate the particles from liquors in which they are suspended is minimized and the amount of liquor recovered is maximized, with minimal dilution by water used for washing. The method includes the steps of a) slaking calcium oxide in water or an alkaline liquor containing as dissolved species predominantly sodium hydroxide; b) mixing the slaked lime with green liquor from a kraft pulping process to complete a causticization reaction that produces white liquor and lime mud; c) separating the lime mud from the white liquor; and d) milling a portion of the lime mud for use as a white mineral pigment in applications where such pigments are typically used.

Lime causticization product brightness improvement via pre-slaking

A method of blending a fine precipitated calcium carbonate (PCC) filler with larger PCC, the resulting blend to be used alone or in conjunction with a ground carbonate, clay or other filler, resulting in improved porosity by the lowering of the porosity of supercalendered paper, thereby imparting improved and offset printability. The fine PCC can be ultrafine PCC filler which then is blended with other fillers including but not limited to pigments. These fillers which are blended with the fine PCC include commercial and experimental PCC and commercial clays. Ultrafine PCC has agglomerates of small, discrete particles. Ultrafine PCC for use in the invention has a specific surface area of about 20 m2/g as measured by BET gas adsorption. As measured by a sedigraph, the average size of these agglomerates is from 0.4 to 1.1 microns.

PCC filler composition for improved printability of supercalendered papers

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Northampton, PA, United States of America

Joseph Andrew Sohara