Sourcing quicklime and hydrated lime from Vietnam: specs and quality checks
What drives lime quality, which specs to put in the contract, and how to sample and test quicklime, hydrated lime and dolomite before shipment.
7 min read Updated
Where Vietnamese lime comes from
Northern Vietnam has large limestone deposits in provinces such as Ninh Binh (which now includes the former Ha Nam province), Thanh Hoa and around Hai Phong. Kilns there supply steel mills, mining, paper, water treatment and chemical plants in Vietnam and across Asia, with Hai Phong as the main export port.
Products and typical specifications
Specs vary by kiln and limestone source. Typical ranges buyers ask for:
- Quicklime (CaO), lump or powder: CaO around 85–95%, with limits on MgO, SiO₂ and loss on ignition
- Hydrated lime (Ca(OH)₂): purity often above 90%, with fineness and moisture limits
- Burnt dolomite: CaO and MgO content, for steel making and refractories
- Particle size: lump ranges such as 10–50 mm, or powder fineness
What determines quality
Three things matter most: the purity of the limestone, the kiln and how evenly it burns, and how the lime is handled after burning. Under-burnt lime contains unconverted limestone; over-burnt (hard-burnt) lime reacts slowly. If your process depends on reactivity, specify a reactivity test method in the contract.
Packaging and transit
Quicklime reacts with moisture and carbon dioxide in the air, so quality can drop between the kiln and your plant. Specify lined jumbo bags or sealed bags, short storage before loading, and dry, clean containers. Ask your carrier early how they classify and accept the cargo.
How to inspect a lime shipment
- Visit the kiln to see the limestone source, kiln type and storage
- Take representative samples during bagging or loading, not only from the top of a pile
- Send samples to an independent laboratory for CaO, MgO, SiO₂, LOI and any reactivity test you need
- Check bag weight, marking, liner integrity and container condition
- Compare results with the supplier's certificate of analysis
Documents to request
A certificate of analysis for the shipped lot, certificate of origin, weight certificate and safety data sheet. If your contract names an inspection company, its certificate should be issued before you pay the balance.
More on this category: specs, HS codes and documents in our Lime, minerals & building materials buyer's guide.
