The dangers of chloride and sulfate
Power plants continuously face corrosion caused by chloride and sulfate under high pressure water and steam conditions. Pitting, stress corrosion cracking and other forms of corrosion attack boiler and steam generator tubes, turbines and other key components in the steam-water cycle. Deposited corrosion causes additional losses through under-deposit corrosion, lowered efficiency and more frequent shutdowns for cleaning.
As a result, monitoring of chloride and sulfate at very low ppb limits is being specified as part of cycle chemistry guidelines and turbine warranty requirements.
Existing measurement technologies have their problems
Demonstrating compliance with these limits has been a challenge for power plants. With a lack of practical on-line measurement technologies, cycle chemistry guidelines have relied on inferred measurements such as cation and degassed cation conductivity. These are important techniques for monitoring water purity during startup, but do not quantify the concentration of chloride and sulfate ions.
Ion Chromatograph and Inductively Coupled Plasma technology provide the separation and sensitivity needed to measure chloride and sulfate at the required low ppb levels. However, the cost of these instruments and the skilled personnel required for their operation places them out of reach for most power plant budgets.
Reliable On-line Measurement
Microfluidic Capillary Electrophoresis technology provides a convenient, dependable method for trace-level chloride and sulfate monitoring. Discover how in our white paper.
The white paper highlights:
- The need for specific chloride/sulfate measurement
- How existing measurement technologies fall short
- Principle of microfluidic capillary electrophoresis
- And more...