What is the approximate level of dissolved oxygen a properly operating steam deaerator can achieve at a minimum?

A properly operating steam deaerator is designed to remove dissolved oxygen from the feedwater to prevent corrosion within the steam system. The effectiveness of a deaerator is influenced by various factors including temperature and pressure, but under optimal conditions, a well-functioning deaerator typically achieves a dissolved oxygen level as low as approximately 0.015 ppm.

This low level is crucial for operational efficiency, as it significantly reduces the risk of corrosion-related issues in the boiler and downstream equipment. The design of a deaerator involves mechanisms that facilitate the removal of gases like oxygen by utilizing steam and creating a vacuum, which enhances the stripping of dissolved gases from the water.

Other levels of dissolved oxygen mentioned in the options do not reflect the minimum achievable concentration in an efficient deaerator. For instance, a level of 0.050 ppm is not typically considered a minimum but might be seen in less efficient systems. Therefore, 0.015 ppm accurately represents the performance standard for a properly operating steam deaerator, ensuring effective protection against corrosion.