Henry's Law states that the amount of gas dissolved in liquid is proportional to its partial pressure in the atmosphere surrounding the liquid, where the system is in temperature equilibrium.
Therefore, to remove oxygen dissolved in water, is sufficient theoretically cancel the partial pressure of this gas in the atmosphere in contact with water, regardless of temperature. Carrying water to the saturation temperature under pressure, automatically dissolved gases into the atmosphere saturated vapor created.
For efficient degassing, the following conditions must be met:
- Sunset water saturation temperature, since its entry into the degassing head. Li>
- Obtaining and maintaining a uniform temperature in the enclosure degassing. Li> ul>
In essence, a degasser consists of two parts. In the upper degassing it is performed and lower the degassed water is stored.
The upper body or degasser itself, is made of stainless steel. It consists of two degassing zones and a device to purge condensable.
Degassed water "condensed, treated water and condensate return" is introduced into the degassing head at the top, through a spray nozzle that sprays water within the degassing head.
The water quickly reaches operating temperature and is held the first degassing; where most of the oxygen has been removed. Then the water passes the second degassing zone mixing chamber. . This chamber, which is made of stainless steel, consists of two concentric bodies:
The outer body is connected with the arrival of steam.
The interior is perforated to allow the passage of steam, which rise to the degassing head is contacted a second time with degassed water, which falls countercurrent. This water undergoes a vigorous washing and this steam bubbling through and reduces even more content-condensable gases.
Finally, the degassed water passes on its way down to the storage tank.
The steam that has not condensed reached, together with the condensable (02, C02, etc.) arrives at the top of the degassing head, where a water cooled coil entry. In this coil most of the vapor condenses, discharging condensable abroad only with a small steam stripping.
The thermal deaerator, will be equipped with the following components and devices:
- Vertical thermal degasser li>
- spray valve. Li>
- horizontal cylindrical storage tank treated water li>
- Connection of degassing head and degassed water tank li>
- Links to: li>
- Input vapor li>
- Two purges boiler li> tickets
- Water supply to degas li>
- Power (2) pumps, boilers li>
- Draw / drain li>
- Vent condensable output li>
- A safety valves li>
- A vacuum breaker valves li>
- visual level indicator li>
- Level Controller li>
- Control safety standards li>
- Overflow water li>
- Thermometer li>
- Gauge li>
- Two transmitter connections pressure / temperature. Li>