Order dense soda ash (99.2% Na2CO3) for float glass, container glass and bulk free-flowing processes; order light soda ash for detergent blending and water-treatment pH adjustment, where it dissolves faster. Standard COA: Na2CO3 99.2% min, NaCl 0.7% max, Fe2O3 0.005% max. It ships in 25/50kg bags or 1000kg jumbo bags — about 25-28 tons per 20ft for dense, only 20-22 tons for light. Shipping takes 20-45 days depending on your port.
Soda ash is the common name for sodium carbonate (Na2CO3), one of the highest-volume industrial chemicals in the world. It is the essential flux in glass melting, an alkalinity builder in laundry detergents, and a pH regulator in water treatment, paper and metallurgy. Because China has large trona and synthetic alkali capacity, buyers across Africa and South America import nearly all their soda ash from Chinese plants. This guide covers the grade to order, the lab values that matter, and the practical container math.
1. Light or dense — which grade to order
"Light" and "dense" are the same chemical (Na2CO3), produced with different processing densities. The difference you feel at the plant is bulk density, dissolution speed and dust:
| Grade | Bulk density | Who should order it |
|---|---|---|
| Soda ash dense | 0.9–1.1 g/cm³ | Float glass, bottle glass, fibreglass and any bulk handling line — free flowing, low dust, fills the furnace hopper cleanly |
| Soda ash light | 0.5–0.6 g/cm³ | Detergent powder mixing, liquid soap alkalinity, water treatment — finer particles dissolve faster in solution |
If you run a glass plant, order dense. If you run a detergent factory, light is usually the right pick — though many big detergent plants also buy dense for low dust in the mixing building. When in doubt, tell your supplier your end use and let them match the grade.
2. The COA values that decide quality
- Na2CO3 ≥ 99.2% — the active content. Below this, you are paying for filler.
- NaCl ≤ 0.7% — salt impurity. High salt attacks refractory lining in glass furnaces and raises corrosion in cleaning systems.
- Fe2O3 ≤ 0.005% — iron. Even a trace tints container glass green and gives detergent powder a greyish tinge. This is the most overlooked number on the certificate.
- Water insoluble ≤ 0.05% — leftover residue after dissolving; matters most for water-treatment and liquid customers.
- Bulk density (declined on the COA) — cheap traders sometimes pass light off as dense by compacting it; check the lab figure against your declared grade.
Always request the batch COA before payment, and a sealed sample before loading so your own lab can cross-check iron and Na2CO3.
3. HS code, packaging and the real container math
Soda ash is classified under HS 2836.20. It is a non-dangerous, general chemical cargo — no DG booking is needed, which keeps freight simple. Packaging options:
- 25 kg or 50 kg bags on wooden pallets, stretch-wrapped — standard for small plants and port-side traders
- 1000 kg jumbo (bulk) bags — for plants with forklift discharge; lowers handling cost per tonne
The container number surprises first-time buyers: because bulk density differs, a 20ft container physically fits 25–28 tons of dense but only 20–22 tons of light. Quote by tonne, not by container, or you will under-calculate your order.
4. Shipping time to your port
- West Africa (Lagos, Tema, Abidjan, Cotonou): about 25–35 days
- East Africa (Mombasa, Dar es Salaam): about 20–30 days
- South America (Callao, Santos, Cartagena): about 35–45 days
Soda ash is hygroscopic: bags exposed to sea humidity can cake into hard blocks by the time they reach inland warehouses. Ask for inner PE liner bags and keep container humidity low in summer bookings.
5. The three most common problems
(1) Caking on arrival — caused by weak outer bags or humid stowage; insist on laminated woven bags with inner liner. (2) Iron too high — brownish-tinted ash from older kilns ruins glass colour; the Fe2O3 line on the COA is non-negotiable. (3) Density mismatch — "dense" that measures like light wastes container space; weigh a small sample before accepting a full container.
SAIFENG supplies soda ash light and dense 99.2% in 25/50kg bags and jumbo bags alongside caustic soda flakes, LABSA and sodium sulfate — the complete raw-material package for glass and detergent plants — to buyers across Africa and South America. Every inquiry is answered within 2 working hours.
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