Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Brine pH modification scale control technology

Conference ·
OSTI ID:494430
 [1]
  1. UNOCAL Corp., Santa Rosa, CA (United States)

UNOCAL`s patented pH modification technologies are applied at several geothermal fields to control siliceous scale deposition. Low dosages of strong acids are injected into brines to inhibit scaling in both flash and heat recovery plants. Testing has shown that pH modification technology can control scaling at low flash pressures and temperatures and at conductive cooling conditions. Typically, brine pH is reduced to the 5 - 6 range to slow the kinetics of silica polymerization without substantially increasing corrosion. Silica scaling rate prediction models and brine titration data are employed to select target acid dosages and pH. Brine injectivity is enhanced by pH modification as a result of scale control and formation stimulation. The use of acid to control siliceous scaling is cost-effective, and affords certain advantages over pH adjustment by acid gas mixing with brine or condensate dilution.

OSTI ID:
494430
Report Number(s):
CONF-960913--
Country of Publication:
United States
Language:
English