From quarry face to loaded truck

Select high-calcium limestone, chosen and characterised before it reaches the kiln.

Everything downstream is decided here. Limestone chemistry — calcium carbonate content, and the silica, magnesia and iron that come with it — sets the ceiling on what the finished lime can be. Deshwali Minerals selects its stone from the Gotan–Borunda limestone belt of Rajasthan for the grade being produced rather than burning whatever is nearest, and feed consistency is what allows a kiln to be run to a repeatable burn rather than being re-tuned batch to batch.

Limestone is burnt in pet coke-fired kilns to drive off carbon dioxide, leaving calcium oxide.

The core transformation: at calcining temperature, calcium carbonate decomposes into calcium oxide and carbon dioxide. Time and temperature together determine reactivity — under-burn leaves residual carbonate, over-burn produces a dead-burnt, sluggish lime. Holding the burn in the right window is what separates a usable industrial reagent from filler. Our kilns are fired with petroleum coke: a high-calorific, low-ash fuel that holds a steady calcining temperature and adds none of the ash that coal firing leaves in the lime.

Material is checked against the specification agreed for the order.

Testing exists to answer one question before despatch: does this consignment match what the customer was promised? For lime that means available lime content, reactivity, size distribution and moisture, checked against the agreed band. Material outside specification is held, not shipped.

Covered storage, then loading for road transport or container export.

Finished goods are held under cover and rotated so the oldest stock ships first. Loading is arranged by consignment size — bagged goods stacked and sheeted, jumbo bags palletised or slung, bulk material in covered tippers. Export consignments are loaded into containers for onward movement.