North American GCC--The finer, brighter side of life

摘要

Chances are, the reader of this article will be surrounded by calcium carbonate in some form or another. In fact, calcium carbonate is probably the most widely used mineral today, with annual US consumption alone exceeding 50m. short tpa. This prevalence stems from a vast sea of applications ranging from cement manufacture and construction materials, to Pharmaceuticals, food preparation, and acid neutralisation. As a mere subset of this mammoth market, what is termed as ground calcium carbonate (GCC) accounts for 3,5-5m, tons of calcium carbonate produced in the USA and Canada each year. Unlike other calcium carbonate markets, however, GCC applications are more specialised, with GCC used as a filler in markets such as paints, plastics, paper, adhesives and sealants, carpet backings, and rubber. What separates GCC from other crushed carbonate grades is primarily particle size, but also purity and brightness. One of the most convenient methods of defining GCC is to apply the requirements for membership to the USA's Pulverized Limestone Association (PLA), ie. a carbonate producer must manufacture and sell a calcitic or dolomitic ground limestone product with a minimum fineness of 97.0 percent passing a 325 mesh sieve, or a mean particle size of approximately 45u.. Such a definition immediately shrinks the hundreds of carbonate producers of North America to less than 30. This article reviews the North American GCC industry with particular emphasis on the changing structure of GCC supply and its future outlook.