Soda Solvay Light, or Solvay process light soda ash, is a sodium carbonate (Na₂CO₃) product produced by the classic Solvay ammonia-soda process, and occupies a unique position in the industrial system. Its production relies on the "ammonia-brine-carbon dioxide" cycle reaction: ammonia is first introduced into saturated salt water to produce ammonia brine, and then CO₂ is introduced to generate sodium bicarbonate precipitation (precipitated due to low solubility), which is then calcined and decomposed to obtain light soda ash, while CO₂ and ammonia are recycled.
From the application point of view, with its loose, porous and highly dispersed physical form, it can quickly assist melting in glass manufacturing, reduce the melting point of raw materials such as quartz sand, and promote uniform mixing of glass liquid; in chemical synthesis, as an alkaline core raw material, it participates in the preparation of sodium salts and carbonates, or is used to adjust the pH of the reaction system. However, if the chlorine-containing waste brine discharged during the production process is not properly handled, it will threaten the soil and water ecology, and it is necessary to match the dechlorination and resource recovery process (such as calcium chloride production); the leakage risk in the ammonia recovery link also puts forward strict requirements for waste gas treatment (scrubber, absorption tower).
Compared with other process soda ash, Solvay Process has a mature circulation system, a significant advantage in ammonia and CO₂ utilization rate (over 90%), and is suitable for large-scale continuous production; but it is limited by chlorine balance, has a high dependence on sea salt resources, and the environmental protection cost is gradually increasing with the tightening of regulations. Today, although it faces competition from the soda ash process and the natural soda process, it still occupies a place in the fields of high-end glass and fine chemicals that have strict requirements on the purity of soda ash (≥99.2%) with its stable quality, and is a typical representative of the iteration of industrial soda ash production technology and environmental protection transformation.
