Method and installation for removing a gas from a flow of a gas mixture

1. A method of removing a gas from a flow of a gas mixture, characterized by:

introducing a first liquid in the flow for evaporative cooling and saturation of the gas mixture;

providing small droplets of a second liquid capable of dissolving said gas and of a size small enough not to be sedimented by gravitation and big enough to be centrifugally separated;

spraying the small droplets into the flow for adsorbing and dissolving said gas into the droplets; and

centrifugally separating the small droplets from the flow,

wherein the gas mixture is a combustion exhaust gas.

2. The method of claim 1 , comprising introducing the first liquid by spraying small droplets thereof into the flow.

3. The method of claim 2 , comprising forming the small droplets of the first liquid by atomization.

4. The method of claim 3 , comprising generating the atomization of the first liquid by pressurized air using a two-fluid nozzle or by high-pressure liquid spray using a single-fluid nozzle.

5. The method of claim 4 , comprising forming the small droplets of the second liquid by atomization.

6. The method of claim 5 , comprising generating the atomization of the second liquid by pressurized air using a two-fluid nozzle or by high-pressure liquid spray using a single-fluid nozzle.

7. The method of claim 2 , comprising controlling the size of the droplets of the first and second liquids to vary between 20 and 200 μm.

8. The method of claim 2 , comprising spraying the droplets of the second liquid downstream of spraying the droplets of the first liquid into the flow.

9. The method of claim 2 , comprising spraying the droplets of the second liquid co-currently with the flow.

10. The method of claim 1 , wherein the first liquid is water and the second liquid is an alkaline water solution.

11. The method of claim 1 , wherein the gas to be removed is a gas comprising sulphur oxides.

12. The method of claim 1 , wherein the gas mixture is an exhaust gas flow from a marine diesel engine and the gas to be removed is a gas comprising sulphur oxides.

13. The method of claim 1 , wherein the first liquid and the second liquid are introduced by spraying small droplets thereof into the flow by atomization, generating said atomization by pressurized air using a two-fluid nozzle or by high-pressure liquid spray using a single-fluid nozzle and further comprising controlling the size of the droplets of the first and second liquids to vary between 20 and 200 μm.

14. An installation ( 10 ) to be inserted in a path of an exhaust flow of an exhaust pipe ( 104 ) for performing the method of claim 10 , characterized by

spray nozzles ( 32 , 42 ) for the water and the alkaline water solution; and

at least one centrifugal separator ( 52 ) downstream of the spraying nozzles in the flow;

said spray nozzles comprising

at least one water spray nozzle ( 32 ); and

at least one atomizing spray nozzle ( 42 ) downstream of the at least one water spray nozzle ( 32 ) in the flow for producing the droplets of the alkaline solution.

15. The installation ( 10 ) of claim 14 , wherein the exhaust pipe ( 104 ) is an exhaust pipe of a marine diesel engine.

16. The installation of claim 14 or 15 , wherein the spray nozzles ( 32 , 42 ) are single fluid nozzles or two-fluid nozzles.

17. The installation of claim 14 , wherein the at least one spray nozzle ( 42 ) is oriented for spraying co-currently with the flow and the at least one spray nozzle ( 32 ) is oriented for spraying counter-currently with the flow.

18. The installation of claim 14 , comprising a control and actuation unit ( 80 ) capable of controlling the size of the droplets in dependence of engine load during operation.