Detailed Project Report (DPR) on ground calcium carbonate

The primary difference is the production method: GCC is mechanically ground, while PCC is chemically produced and precipitated. GCC starts with naturally occurring limestone or marble that is crushed and milled to the required particle size. PCC is manufactured through a chemical process in which calcium carbonate is precipitated from a solution. This difference in production route can influence particle characteristics, purity, morphology, and the applications for which each material is selected.

GCC production can use Air Classifying Mills, Pulveriser Hammer & Screen Mills, or ball mill and air classifier systems depending on the required product fineness. An Air Classifying Mill provides controlled particle-size distribution and can produce coarse through fine grades. Pulveriser Hammer & Screen Mills are suited to coarser calcium carbonate products and require less air and ancillary equipment. For ultra-fine milling with D50 < 5 µm, the report identifies the Hosokawa Alpine Super Orion Ball Mill and Air Classifier as an appropriate option.

An Air Classifying Mill can produce calcium carbonate from coarse 100 mesh grades down to approximately 635 mesh, corresponding to 20 µm, with D50 of less than 5 µm also possible. The internal air classifier controls particle size and helps provide a sharp particle-size distribution. The appropriate configuration depends on the intended product specification. Abrasion-resistant options such as tungsten carbide tipping, Ni-Hard, or ceramic liners may also be selected where abrasive impurities such as quartz or sand are present in the limestone feed.

The proposed Green Field Ground Calcium Carbonate production facility has an installed capacity of 36000 Tons / Year. The cost estimation section of the report separately states a plant capacity of 120 Tons/Day. These project-specific figures have been retained exactly as provided. Actual plant performance can depend on raw material characteristics, equipment configuration, operating conditions, product specifications, maintenance requirements, and the number of operating days considered in the project planning basis.

Limestone quality is important because chemical purity, colour, and abrasive impurities affect the quality and processing of GCC. Calcium carbonate is relatively soft, with a Mohs hardness of 2.5 – 3.0, but mined limestone can contain abrasive materials such as quartz or sand. These impurities can influence equipment wear and product suitability. Consequently, raw material evaluation and appropriate mill configuration are important considerations when designing a GCC production facility for specific end-use requirements.

Equipment selection should primarily consider the required particle size, product specification, raw material characteristics, and operating requirements. Coarser calcium carbonate products may be produced economically with a Pulveriser Hammer & Screen Mill, while an Air Classifying Mill provides greater control over particle-size distribution and can handle finer grades. Ultra-fine applications may require a ball mill with an air classifier. Where abrasive impurities are present, abrasion-resistant mill components can help extend equipment service life.