High-temperature corrosion continued steam

High pressure water systems are also available that heat by continuously circulating hot water. The advantage is less corrosion than steam since the oxygen is not replenished in the closed circuit. Also, temperatures are more uniform than steam because, like hot oil, it is a dynamic system. These systems are expensive and costly to maintain. 

Conductivity measurement with contact electrodes is used in many different process analytical applications. In all of them the main interest is to detect the presence of ionic species in the sample. The effectiveness of distillation and demineralization units is normally controlled by continuous measurement of the conductivity of the outgoing stream. Any defect in the operation of the unit can immediately be seen in the increase in conductivity. The feeding water to steam turbines has to be as clean as possible in order to avoid corrosion in the system that operates under high pressure and at elevated temperatures. The conductivities of feeding water as well as the condensed steam are also continuously monitored by conductivity measurement. Increased conductivity is an immediate indication of corrosion in the system or leakage in the cooling system. This is of extreme importance in nuclear power plants where among other risks corrosion products may also become activated. 

---