New York Low Pressure Boiler COF Practice

Which of the following methods is used to remove oxygen from feedwater?

1. Chlorination

2. Heating

3. Tray deaerators

4. Filtration

The correct answer is: Tray deaerators

The method used to remove oxygen from feedwater is through the use of tray deaerators. Tray deaerators are specially designed systems that utilize heat and mass transfer to strip dissolved gases, particularly oxygen, from water. In this process, water is heated, and it flows over a series of trays or packing, allowing steam to rise through the water. This interaction helps to displace and remove unwanted gases, thus significantly reducing the oxygen content in the feedwater. In industrial boiler operations, minimizing oxygen in the feedwater is crucial because dissolved oxygen can cause corrosion within the boiler and piping systems, leading to costly damage and maintenance issues. By effectively using tray deaerators, operators can maintain water quality and ensure the longevity of their equipment. Other methods listed may not specifically target the removal of oxygen effectively. For instance, while heating can help increase the temperature of water, it alone does not necessarily remove dissolved gases. Chlorination is primarily used for disinfection purposes, and filtration mainly deals with particulate matter rather than dissolved gases like oxygen. Thus, tray deaerators stand out as the most effective and widely used method for oxygen removal in boiler feedwater treatment.