Sodium Chloride (Large Granular)

Updated: 2026-07-15

Overview

Large granular sodium chloride, often referred to as rock salt or halite, is a naturally occurring mineral composed primarily of sodium chloride (NaCl). This coarse form of salt is distinguished from table salt by its larger crystal size, typically ranging from 2-10 mm in diameter. It forms through the evaporation of ancient seawater and is commonly mined from underground salt deposits. The industrial production of large granular sodium chloride involves either mining from rock salt deposits or evaporation of brine solutions. The product is then crushed and screened to achieve the desired particle size distribution. Unlike refined table salt, large granular sodium chloride often contains trace minerals that give it slight color variations.

Physical and Chemical Properties

Large granular sodium chloride shares the same fundamental chemical properties as other forms of NaCl, including its cubic crystal structure and high solubility in water. The coarse particles have a slower dissolution rate compared to fine salts, making them particularly suitable for applications requiring controlled release. The physical properties of large granular sodium chloride include a Mohs hardness of 2-2.5, making it relatively soft compared to many other minerals. Its density of 2.16 g/cm³ means it's heavier than water, and the large particle size reduces dust formation during handling. The material is stable under normal conditions but can absorb moisture from humid environments due to its hygroscopic nature.

Main Applications

One of the primary uses of large granular sodium chloride is for road de-icing during winter months. The coarse particles provide better traction than fine salt and dissolve more slowly, offering longer-lasting effects. In water treatment, it's used for regenerating ion exchange resins in water softeners, where the large size prevents clogging of the resin bed. The food industry utilizes large granular sodium chloride for curing meats and in fermentation processes. Its slow dissolution rate makes it ideal for brining applications. Industrial chemical production also consumes significant quantities as a raw material for chlorine and sodium hydroxide production through electrolysis. Other applications include livestock feed supplementation and oil drilling operations.

Safety and Storage

While sodium chloride is generally considered safe, large granular forms present specific handling considerations. The coarse particles can be abrasive to skin during prolonged contact, and dust generated during processing may irritate respiratory passages. Proper personal protective equipment including gloves and dust masks should be used during bulk handling. Storage requirements for large granular sodium chloride include keeping the product in dry conditions to prevent caking. Although non-flammable, it should be stored away from strong acids or bases. Outdoor storage is acceptable if protected from precipitation, but covered storage is preferred to maintain product quality. Bulk storage facilities should have proper drainage to handle any potential runoff.

B2B Procurement Guide

When procuring large granular sodium chloride for industrial use, buyers should specify key parameters including particle size distribution (typically 2-5mm or 5-10mm), purity level (usually 95-99% NaCl), and moisture content. Food-grade applications require additional certifications and testing for contaminants. Packaging options range from bulk shipments in hopper cars or trucks for large-volume users to 50kg bags or supersacks for medium-scale operations. Consider proximity to salt mines or production facilities to minimize transportation costs. Seasonal demand for de-icing salt can affect availability and pricing, so forward purchasing is recommended for winter applications. Quality assurance should include testing for insolubles and trace mineral content.