What is the minimum operating pressure at which sodium ions must be removed?

In the context of power engineering and the operation of boilers or steam systems, the removal of sodium ions is critical to preventing issues such as scaling and corrosion in the system. Sodium ions can contribute to deposit formation, which negatively affects heat transfer efficiency and can lead to failures.

The minimum operating pressure for effective sodium ion removal is significant because, at higher pressures, specific chemical equilibria can shift, allowing for better management of impurities such as sodium. Systems operating above 4000 kPa, typically in high-pressure steam applications, use advanced treatment processes where the removal of sodium ions becomes more efficient and necessary to maintain system integrity and performance.

Operating above this threshold ensures that the conditions are suitable for the processes in place to effectively remove these ions, thus protecting the equipment from potential damage caused by sodium-related issues. Therefore, the selection of "Above 4000 kPa" indicates a level of understanding regarding the importance of maintaining water quality in high-pressure steam systems, where sodium ion management is crucial.