Specialty Minerals Precipitated Calcium Carbonate (PCC) Merchant Plants

A PCC satellite plant and a PCC merchant plant are capable of manufacturing virtually the same precipitated calcium carbonate (PCC) products. Satellite PCC plants typically supply a single host paper mill. Merchant plants, however, can service a number of paper mills within a geographical radius and may be located near the limestone or lime source. Since the 1930’s, Specialty Minerals has been producing PCC at our Adams, Massachusetts, facility, which is much larger than a typical satellite counterpart, and is capable of producing a full range of PCC products, both dry and slurry. Specialty Minerals also has PCC merchant facilities in the United Kingdom and Germany.

This diagram shows a typical precipitated calcium carbonate merchant plant layout. 

Quicklime (CaO) is delivered locally or from carefully chosen regional sources and stored in large tanks. It is then mixed with water in a "slaker" to form "slake" or calcium hydroxide (Ca(OH)2) and the slurry stored in a holding tank. The slurry is then led to a "carbonator" tank where the slaked lime is reacted with carbon dioxide (CO2) gas. After careful screening, the PCC slurry is delivered to a paper mill in rail tank cars or trucks. Alternatively, the PCC slurry can be dried and bagged for rail or truck shipment to the user. Throughout the process, reaction conditions of time, temperature and pressure are monitored and controlled. Quality checks are made at various stages in the process and again just before delivery.

All of Specialty Minerals’ modern precipitated calcium carbonate merchant plants are equipped with the latest process automation and equipment technology.