KM-788 Defoamer for Phosphoric Acid Concentration: Viscosity & Scaling Control

Foam in phosphoric acid concentration (＞30% solids, ＞100°C) causes scaling in evaporators, reducing heat transfer efficiency by 40%6. A Guizhou plant using Chemi Tech KM-788 (polyether ester-stearate composite) resolved：

Heat transfer coefficient increased from 980 to 1,120 W/(m²·K)；

Evaporator cleaning cycle extended to 90 days (scale thickness ＜1mm)；

Viscosity stabilized below 120 mPa·s at 70°C.

Technology:

High-temperature resistant groups sustain ＞4 hours of activity at 110°C. Magnesium stearate adsorbs colloids (e.g., fluosilicates) to inhibit scaling and viscosity spikes.

Verification:

Added 0.25% in 42% P₂O₅ concentration system：

Steam consumption reduced 18%, saving ¥1.2 million/year in coal costs；

Vacuum stability maintained at -0.085MPa (fluctuation ＜5%)；

Residual fluorine in acid ＜50ppm.