Deaeration system and method for deaeration
A system for deaerating a liquid comprises a separation vessel where deaerated liquid is separated from gas, predominantly air; a liquid inlet to the separation vessel through which the liquid enters the separation vessel; a liquid outlet from the separation vessel through which a deaerated liquid exits the separation vessel, and a gas outlet through which the gas exits the separation vessel. The liquid inlet is arranged at a first end of the separation vessel and is configured to give the liquid entering the separation vessel a trajectory, and wherein a stop plate is arranged in the trajectory to abruptly stop the propagation of liquid travelling along the trajectory.
1. A method for deaerating a liquid, comprising the steps of:
pressurizing the liquid to a pressure P 0 ,
depressurizing the liquid to a pressure P 1 , above the boiling point of the liquid,
injecting the liquid through a liquid inlet into a separation vessel along a trajectory, such that the liquid impacts a stop plate arranged in the separation vessel,
guiding the liquid from the liquid inlet arranged in a first end of the separation vessel towards a liquid outlet arranged in a second end of the separation vessel, the second end being in an opposed end of the separation vessel as compared to the inlet,
subjecting the liquid to the pressure P 1 while the liquid is in the separation vessel, such that the liquid is prevented from boiling, and
by using a recovery system:
deaerating liquid leaving through a gas outlet arranged in the separation vessel to recover liquid from the gas outlet, and
guiding the recovered liquid via a recovery line back to the deaerated liquid, upstream or downstream the liquid outlet,
wherein the pressure drop, P 0 -P 1 , is in the range of 2 to 5 bar.
2. The method of claim 1 , wherein the separation vessel has an elongated shape in a horizontal longitudinal direction.
3. The method of claim 1 , wherein the separation vessel has a flattened cross section in a horizontal cross direction, orthogonal to a horizontal longitudinal direction.
4. The method of claim 1 , wherein the separation vessel has an oval or elliptic cross section in a horizontal cross direction, orthogonal to a horizontal longitudinal direction.
5. The method of claim 1 , wherein the liquid inlet is arranged at 65-80% of a height of the separation vessel.
6. The method of claim 1 , wherein the depressurizing is realized by a throttling point directly upstream the liquid inlet or a throttling point constituting the liquid inlet.
7. The method of claim 2 , wherein the liquid inlet is arranged at 65-80% of a height of the separation vessel.
8. The method of claim 2 , further comprising, by using a recovery system,
deaerating liquid leaving through a gas outlet arranged in the separation vessel to recover liquid from the gas outlet, and
guiding the recovered liquid via a recovery line back to the deaerated liquid, upstream or downstream the liquid outlet.
9. The method of claim 2 , wherein the depressurizing is realized by a throttling point directly upstream the liquid inlet or a throttling point constituting the liquid inlet.
10. The method of claim 3 , wherein the liquid inlet is arranged at about 65-80% of a height of the separation vessel.
11. The method of claim 3 , further comprising, by using a recovery system,
deaerating liquid leaving through a gas outlet arranged in the separation vessel to recover liquid from the gas outlet, and
guiding the recovered liquid via a recovery line back to the deaerated liquid, upstream or downstream the liquid outlet.
12. The method of claim 3 , wherein the depressurizing is realized by a throttling point directly upstream the liquid inlet or a throttling point constituting the liquid inlet.
13. The method of claim 4 , wherein the liquid inlet is arranged at 65-80% of a height of the separation vessel.
14. The method of claim 4 , further comprising, by using a recovery system,
deaerating liquid leaving through a gas outlet arranged in the separation vessel to recover liquid from the gas outlet, and
guiding the recovered liquid via a recovery line back to the deaerated liquid, upstream or downstream the liquid outlet.
15. The method of claim 4 , wherein the depressurizing is realized by a throttling point directly upstream the liquid inlet or a throttling point constituting the liquid inlet.
16. The method of claim 5 , wherein the liquid inlet is arranged at 70-75% of a height of the separation vessel.
17. The method of claim 7 , wherein the liquid inlet is arranged at 70-75% of a height of the separation vessel.
18. The method of claim 10 , wherein the liquid inlet is arranged at 70-75% of a height of the separation vessel.
19. The method of claim 13 , wherein the liquid inlet is arranged at 70-75% of a height of the separation vessel.