Defoamer for High-Carbonate Phosphate Rock in Wet-Process Acid

High-carbonate phosphate rock (＞4% CaCO2) generates thick foam layers (300-700mm) during acid digestion, reducing reactor capacity by 30% and causing P2O5 losses16. A Vietnam acid plant using Chemi Tech KM-8800 (non-silicone type defoamer) achieved:

Foam layer thickness controlled below 100mm at 0.3kg/t-acid dosage；

P2O5 recovery increased by 3.8%, lowering ore consumption per ton acid；

Compatibility in pH 1.5-2.5 and 80-85°C conditions without affecting flash evaporation.

Mechanism:

Low surface tension (＜24 mN/m) penetrates CO2 foam films；

Hydrophobic chains encapsulate organics (e.g., humic acid) to destabilize foam；

Nano-carriers (＜1 μm) enhance dispersion in slurry.

Case: Applied to Vietnamese high-carbonate ore (6.2% CaCO2)：

Zero overflow accidents with foam reduction from 650mm to 80mm；

Filtration intensity increased 15%, filter cake moisture stabilized below 24%；

Annual defoamer cost savings: ￥570,000 vs. imported alternatives.