JP2023124826A5

JP2023124826A5 -

Info

Publication number: JP2023124826A5
Application number: JP2023021285A
Authority: JP
Filing date: 2023-02-15
Publication date: 2024-05-17

Claims

A crosshead type large two-stroke turbocharged uniflow scavenging internal combustion engine,
a plurality of combustion chambers each defined by a cylinder liner, a piston configured to reciprocate within the cylinder liner, and a cylinder cover;
a scavenging port for introducing scavenging gas into the combustion chamber, the scavenging port being disposed in the cylinder liner;
an exhaust outlet disposed in the cylinder cover and controlled by an exhaust valve;
a fuel system configured to supply a carbon-based fuel to the combustion chamber;
Equipped with
The combustion chamber is configured to combust the carbon-based fuel and generate combustion gases including carbon dioxide;
The combustion chamber is connected to a scavenging air receiver via the scavenging port and is connected to a combustion gas receiver via the exhaust outlet ,
The engine further includes an exhaust gas recirculation system configured to recirculate a portion of the combustion gases discharged from the combustion chamber to the scavenging receiver;
the exhaust gas recirculation system includes a blower for assisting the flow of combustion gases to the scavenge air receiver;
The engine further includes an exhaust system configured to exhaust another portion of the combustion gases generated from the combustion chamber as exhaust gases;
the exhaust system includes a turbine of a turbocharging system, the turbine being driven by exhaust gases;
the engine further comprises an air intake system having a compressor of the turbocharging system, the compressor being configured to supply pressurized scavenging air to the scavenging air receiver;
The exhaust system includes a carbon dioxide separator and a carbon dioxide storage unit connected to an outlet of the carbon dioxide separator;
the carbon dioxide separation device is configured to receive the flue gas and separate at least a portion of the carbon dioxide in the flue gas from the flue gas, preferably by liquefying and/or solidifying the carbon dioxide, and deliver the separated carbon dioxide to the carbon dioxide storage unit;
institution.

The engine of claim 1, further comprising a control configured to adjust the mass ratio of recirculated combustion gas in the scavenging gas to at least 40%, preferably between 40% and 55%.

The engine of claim 2, wherein the control unit is configured to control the rotational speed of the blower to adjust the proportion of recirculated combustion gas in the scavenging gas.

An engine according to any one of claims 1 to 3, comprising a combustion gas-water cooler, preferably a combustion gas-seawater cooler, preferably located upstream of a position where the flow of combustion gas from the engine is divided into a portion that is recirculated and another portion that is exhausted.

4. An engine according to any one of claims 1 to 3 , comprising a combustion gas-cooling medium heat exchanger and a cooling arrangement arranged to circulate a cooling medium through the combustion gas-cooling medium heat exchanger, the combustion gas-medium heat exchanger preferably being arranged downstream of a position at which a flow of combustion gases from the engine is divided into a recirculated portion and another portion which is exhausted.

4. An engine according to claim 1, further comprising, downstream of the turbine, a cooler for cooling the exhaust gas in order to liquefy and/or solidify carbon dioxide therein.

The engine according to claim 2 , wherein the control unit is configured to control operation of the engine so that the temperature of the exhaust gas is −82° C. or lower when the exhaust gas reaches atmospheric pressure downstream of the turbine.

An engine according to any preceding claim, wherein the turbine is mechanically coupled to drive the compressor, preferably assisted by an electric drive motor.

4. An engine according to any preceding claim, wherein the compressor is driven by an electric drive motor and the turbine drives an electric generator or alternator.

1. A method of operating a large two-stroke turbocharged uniflow scavenged internal combustion engine having multiple combustion chambers, comprising the steps of:
supplying a carbon-based fuel to the combustion chamber;
combusting the carbon-based fuel in the combustion chamber to generate combustion gases comprising carbon dioxide;
recirculating a portion of the combustion gas and discharging another portion of the combustion gas as exhaust gas;
supplying a pressurized scavenging gas to the combustion chamber, the scavenging gas comprising at least 40 mass %, preferably 40 to 55 mass %, of recirculated combustion gas;
separating carbon dioxide from the flue gas in a carbon dioxide separation process;
storing the separated carbon dioxide in a storage unit;
A method comprising:

11. The method of claim 10, comprising subjecting the exhaust gas to one or more cooling and expansion processes, thereby liquefying and/or solidifying carbon dioxide downstream of a turbine of a turbocharging system of the engine .

The method of claim 11 , wherein at least a portion of the expansion process occurs in the turbine.

12. The method according to claim 11, wherein the engine comprises a cooler downstream of the turbine for further cooling the exhaust gas in order to liquefy and/or solidify the carbon dioxide therein, preferably to a temperature of -80 ° C or lower at atmospheric pressure.

14. The method of any of claims 10 to 13 , comprising storing carbon dioxide in liquid or solid form in the storage unit.

14. A method according to any one of claims 10 to 13 , comprising controlling the speed of a blower in an exhaust gas recirculation system to adjust the proportion of recirculated combustion gas in the pressurized scavenging gas.

A method according to any of claims 10 to 13 , wherein the engine has a combustion gas-water cooler, preferably an exhaust gas-sea water cooler, preferably located upstream of a location where a flow of combustion gases from the engine is divided into a recirculated portion and another portion which is exhausted, the method comprising cooling the combustion gases in the combustion gas-water cooler, preferably to a temperature of 40°C or less, more preferably 31°C or less.

A method according to any of claims 10 to 13 , wherein the engine is provided with a combustion gas-cooling medium heat exchanger, preferably downstream of a position where a flow of combustion gases from the engine is divided into a recirculated portion and another portion which is exhausted, and further comprising cooling equipment, the cooling equipment being arranged to circulate a cooling medium through an exhaust gas-cooling medium heat exchanger and to cool the exhaust gases, preferably to below -10°C, more preferably to below -15°C.