Reasons for gas generation in the drum and high NA ion levels in the steam
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The gas generation rate of the catalytic external heat exchanger is below 30 t/h; the NA ion level in the steam is normal. When the gas generation rate exceeds 35 t/h, the NA ion content in the steam becomes too high, resulting in steam of substandard quality. What causes this? Please ask an expert to help answer.
Trisodium phosphate is added based on the pH value of the boiler water, and it is added as part of the normal routine.
The cyclone separator came loose, causing the steam and water to be discharged directly without separation; this is the main reason for the elevated levels of steam conductivity and Na+. The main reason for the separator falling off, as analyzed, is that no backstop measures for the fixing pins of the steam-water separator were considered during design, and no effective fixing measures were taken during installation.
The factors affecting steam quality can be divided into two aspects: one is the water carried by the steam, and the other is the impurities dissolved in the steam. The ability of steam to dissolve impurities is related to the steam pressure; the higher the pressure, the greater the dissolving capacity. Saturated steam at a pressure of 2.94 MPa to 3.92 MPa has a significant ability to dissolve silicic acid, and when the pressure of the saturated steam exceeds 12.74 MPa, it can also dissolve various sodium compounds. Steam dissolution of impurities occurs mainly in large-capacity, high-pressure boilers; it is not a concern for boilers operating at medium temperature and pressure