High dissolved oxygen in the deaerator

1. Check whether the temperature of the heated water has reached the designed value; if not, adjust the heating system to ensure that the water temperature is sufficient. 2. Check for any air leaks in the deaerator, paying special attention to the air intake system and seals, as well as the seals at the top of the deaerator. Any minor leakage can lead to excessive dissolved oxygen levels. 3. Check whether the oxygen content in the raw water entering the deaerator is within the normal range; if the oxygen content in the raw water is too high, it will also affect the deoxygenation effect. 4. Consider optimizing the hydrodynamic conditions of the water in the deaerator, such as adjusting its internal structure, increasing the contact area, and optimizing the water flow path. 5. If the problem persists despite the above steps, it is recommended to consult the equipment manufacturer or a professional technician for a thorough inspection and maintenance. .

40 ppb – what corresponds to an oxygen level of 0.04 mg/L? Boiler pressure

Thank you very much. Our heating temperature has reached the designed level, for the medium-pressure boiler； The deaerator is required to operate at a temperature of 104 degrees. Regarding the air leakage you mentioned, the entire equipment was checked and no external leaks were found; moreover, the deaerator maintains a pressure of 15–20 kPa.

Yes, the pressure of the boiler is less than 2.5 Mpa; it is designed to operate at 104 degrees with operating parameters of 15 kpa. The water supply was tested, and the dissolved oxygen level in the water was also only 2000–3000 ppb ； The instruments are fine; the two tanks are connected, and the readings are similar, so they can be compared. The steam consumption is approximately 2000 kg/h. We conduct online tests for dissolved oxygen, and we also use other instruments for inspections

I don’t know that much about this thing yet, ah

Consult the deaerator manufacturers; ask the newly built factory to send someone to carry out adjustments, or contact the party that installed this equipment. Steam consumption is related to the water supply volume; it’s hard to understand how such a situation can occur when the temperature rises and there are no issues with the exhaust steam. It’s either intuition or the equipment isn’t properly tuned; there might be issues with the distribution of water mist and the mixing of steam and water. Thermal deaerators are mature devices, and they operate quite reliably once tuned properly. (There have been lessons from situations where thermal deaeration was discontinued and only so-called new-type deaeration agents were used, resulting in continuous tube failures on the non-wearing surfaces of the boiler.)

It is recommended that the poster conduct a thorough inspection of the online trace oxygen analyzer, focusing on all sampling pipelines, connectors, and components of the small instrumentation system, to check for any plastic pipelines, especially hoses Also, is the detection probe of the analyzer system being properly maintained and calibrated? Regarding the deaerators of thermal or power boilers, I personally believe that under the specified operating conditions of temperature and pressure, as long as no air leaks in, the deaeration effect is reliable and trustworthy. If problems with the process equipment and operations can be ruled out, then an excessive level of dissolved oxygen is most likely due to issues with the configuration and design of the analysis system. Trace dissolved oxygen cannot be verified through laboratory sampling and analysis; problems can only be identified by conducting a thorough inspection of the instrument system on-site. The poster can take photos or videos of the entire online analyzer system and send them over so I can take a look.

Pay attention to controlling temperature and pressure; it is necessary to calibrate them regularly. This problem has never occurred in high-pressure boilers and sub-high-pressure boilers.