bulk
Unpackaged goods when transported in large volumes, e.g. coal, ore, or grain.
bulk: cargo shipped loose, not in boxes or bags
Bulk cargo is any unpackaged or minimally packaged commodity transported in large quantities by weight or volume rather than by unit count. Common bulk commodities include coal, iron ore, grain, cement, sand, sugar, salt, and crude oil. The defining feature is that the goods flow freely, are loaded directly into the hold of a ship, truck, or rail wagon, and discharged by mechanical means such as grabs, pumps, or conveyors rather than handled piece by piece.
Bulk transport is radically more cost-effective than containerized or palletized shipping because it eliminates packaging material, reduces handling labor, and maximizes cargo density per voyage. A bulk carrier vessel might move 50,000 to 80,000 metric tons of ore or grain in a single journey. For shippers of commodity materials, the per-ton cost difference between bulk and general cargo can be the margin between profit and loss on thin-margin products like fertilizer or coal.
Dry bulk versus liquid bulk
Dry bulk covers solid commodities: grains, ores, coal, aggregates, and minerals. These are loaded via conveyor belts, chutes, or continuous grab cranes. Liquid bulk covers oil, chemicals, molasses, and liquefied gases, transported in tanker ships or specialized road and rail tankage with internal compartments and pumping gear. The two require entirely different infrastructure, handling equipment, and regulatory compliance frameworks.
Bulk handlers must manage significant practical challenges. Moisture content in grain or ore can cause cargo shift during transit, potentially capsizing a vessel or derailing a train. Fine powders like cement generate dust that damages equipment and poses health hazards. Corrosive bulk materials such as certain chemicals or sulfur require specialized tank linings. Weather protection is often minimal, so rain or sea spray can degrade unprotected cargo. Bulk terminals invest heavily in dustless loading systems, enclosed transfer systems, and sophisticated ventilation.
The term 'bulk' originated in maritime trade and refers to the fundamental nature of these cargoes: they are sold and shipped in bulk quantities, measured by weight or cubic capacity, rather than as discrete items or units. This remains the core distinction in transport economics and logistics planning today.