With continued growth in global photovoltaic (PV) module installations, the demand profile for soda ash (sodium carbonate, Na₂CO₃)—a key fluxing agent in PV glass production—is evolving. Technical requirements for soda ash in PV glass lines include the following parameters:
Total alkalinity (as Na₂CO₃ dry basis) ≥99.2%
Iron (Fe) content ≤0.003% to prevent light transmittance loss in glass
Sodium chloride (NaCl) content ≤0.7% (standard industrial grade suitable for most lines)
Particle size distribution: Dense soda ash (bulk density ≥0.9 g/ml) suitable for continuous feeding systems in large glass furnaces
From a process perspective, PV glass melting temperatures are typically controlled between 1500°C and 1560°C. Soda ash acts as a flux to lower the melting point of silica sand, reducing melting energy consumption. In recent years, some glass manufacturers have imposed stricter requirements on batch-to-batch consistency, including total alkalinity variation controlled within ±0.2%.
On the supply side, major export ports such as Tianjin and Qingdao maintain regular stocks of dense soda ash. Packaging is typically 1000kg or 1200kg jumbo bags with moisture-proof inner liners. Buyers are advised to specify in contracts that a Certificate of Analysis (COA) be provided per batch, with test items including iron content, sodium chloride content, and bulk density.
