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A cogeneration plant is provided that includes a gas turbine, a heat recovery steam generator, a steam turbine and a cooler/condenser. A division module is provided at a division point, via which downstream the heat recovery steam generator the combustion gas is cooled and dehumidified in the cooler

A cogeneration plant is provided that includes a gas turbine, a heat recovery steam generator, a steam turbine and a cooler/condenser. A division module is provided at a division point, via which downstream the heat recovery steam generator the combustion gas is cooled and dehumidified in the cooler/condenser and then divided into a first combustion gas flow and a second combustion gas flow. A second condenser is provided for receiving the second combustion gas flow to separate contained carbon dioxide from contained water by condensation of the water. The cogeneration plant further includes a heater and a compressor for receiving the first combustion gas flow, which is heated, compressed and partly extracted to by-pass the combustor for cooling of the gas turbine before it enters the combustor and mix with the flow of oxygen and fuel to be burned in the gas turbine.

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1. A cogeneration plant for burning a fossil fuel with pure oxygen in a gas turbine cycle for generation of a combustion gas utilized for heating water into steam in a steam cycle, the cogeneration plant comprising: the gas turbine cycle, andthe steam cycle,wherein the gas turbine cycle comprises: a

1. A cogeneration plant for burning a fossil fuel with pure oxygen in a gas turbine cycle for generation of a combustion gas utilized for heating water into steam in a steam cycle, the cogeneration plant comprising: the gas turbine cycle, andthe steam cycle,wherein the gas turbine cycle comprises: a gas turbine for expanding the combustion gas,a combustor of the gas turbine that burns a mixture of the fossil fuel with the pure oxygen, and a recirculated first combustion gas flow of the combustion gas, for generating the combustion gas to be expanded,a heat recovery steam generator arranged downstream the gas turbine that receives the combustion gas to heat liquid water and steam, resulting in steam and/or superheated steam,a division module at a division point, via which, downstream the heat recovery steam generator, the combustion gas is divided into the recirculated first combustion gas flow and a second combustion gas flow, anda compressor that receives the recirculated first combustion gas flow, which is compressed to enter the combustor and mix with a flow of the mixture of the fossil fuel with the pure oxygen to be burned in the gas turbine,wherein the steam cycle comprises: a steam turbine, via which the steam is expanded,a first condenser arranged downstream the steam turbine, via which the expanded steam is at least partially condensed to the liquid water,a first pump that delivers the liquid water with increased pressure to the heat recovery steam generator to be heated up by heat exchange with the combustion gas,a cooler/condenser that receives the combustion gas is provided downstream the heat recovery steam generator, wherein the cooler/condenser is configured to cool the combustion gas and cause a humid fraction of the combustion gas to be partly condensed into the liquid water and drained, wherein downstream a heat exchange in the cooler/condenser, the combustion gas is divided by the division module into the recirculated first combustion gas flow and second combustion gas flow,a heater that is configured to heat and de-liquefy the recirculated first combustion gas flow with a cooling medium from the cooler/condenser after being heated up via the heat exchange in the cooler/condenser, which the heater is provided downstream the division module and upstream the compressor for heating and de-liquefying the recirculated first combustion gas flow before supplying the recirculated first combustion gas flow to the compressor, anda second condenser to which the second combustion gas flow is submitted in order to cool down a mixture of water and carbon dioxide, wherein the second condenser is configured such that in the second condenser a part of the humid fraction of the second combustion gas flow is condensed into water, which is separated from the rest of the mixture of water and carbon dioxide. 2. The cogeneration plant according to claim 1, wherein the cooler/condenser-module cools the combustion gas down to a temperature of between 65° C.-75° C. 3. The cogeneration plant according to claim 1, wherein the cooler/condenser partly condensates a vapor fraction of the combustion gas into liquid phase. 4. The cogeneration plant according to claim 1, wherein the cooler/condenser is cooled by a cooling medium separated from the steam cycle. 5. The cogeneration plant according to claim 4, wherein the cooling medium is selected from a group consisting of: sea water, ambient air, ambient air via an intermediate water system, and water from a district heating grid. 6. The cogeneration plant according to claim 1, wherein a compressor and intercooler system is provided downstream of the second condenser receiving the second combustion gas flow to reduce the moisture content by separating water from the second combustion gas flow, wherein the remaining carbon dioxide is compressed and cooled to liquid phase. 7. The cogeneration plant according to claim 1, wherein the compressor of the gas turbine cycle compresses the recirculated first combustion gas flow up to a pressure in the combustor of between 25 bar-55 bar. 8. The cogeneration plant according to claim 1, wherein an extraction module is provided to extract a flow of cooling steam at an extraction point within an expansion process of the steam in the steam turbine to be supplied to a cooling system of the gas turbine as a cooling fluid and, which flow of the cooling steam is at least partially reunited with a main flow of the steam during or after the expansion process of the steam in the steam turbine downstream the extraction point via a feeding module. 9. The cogeneration plant according to claim 8, wherein a portion of the flow of cooling steam is partially injected into a hot gas path of the gas turbine for cooling purpose. 10. The cogeneration plant according to claim 1, wherein the cooler/condenser-module cools the combustion gas down to a temperature of between 55° C.-85° C. 11. A method of burning a fossil fuel with pure oxygen in a gas turbine cycle of a cogeneration plant for the generation of a combustion gas utilized for heating water into steam in a steam cycle, the method comprising: in the gas turbine cycle: generating the combustion gas by burning a mixture of the fossil fuel with the pure oxygen, and a re-circulated first combustion gas flow of the combustion gas in a combustor,expanding the combustion gas in a gas turbine,heating water into steam in the steam cycle in a heat recovery steam generator utilizing the combustion gas as the heating medium,compressing the recirculated first combustion gas flow re-circulated from the heat recovery steam generator,supplying a major fraction of the recirculated first combustion gas flow to the combustor,in the steam cycle: generating the steam in the heat recovery steam generator,expanding the steam in a steam turbine,condensing the steam after expansion into water with a first condenser,re-circulating the water to the heat recovery steam generator,cooling and/or condensing the combustion gas downstream the heat recovery steam generator in a cooler/condenser, which causes a humid fraction of the combustion gas to be partly condensed into the liquid water and drained,wherein downstream a heat exchange in the cooler/condenser, the combustion gas is divided by a division module into the recirculated first combustion gas flow and second combustion gas flow,dividing with the division module at a division point downstream a heat exchange in the cooler/condenser, the combustion gas into the recirculated first combustion gas flow and a second combustion gas flow,supplying the recirculated first combustion gas flow to a heater,heating and de-liquefying with the heater the recirculated first combustion gas flow before the compression of the recirculated first combustion gas flow using a cooling medium from the cooler/condenser after being heated up via the heat exchange in the cooler/condenser, wherein the heater is provided downstream the division module and upstream the compressor, andsubmitting the second combustion gas flow of the combustion gas to a second condenser in order to cool down a mixture of water and carbon dioxide, wherein in the second condenser a part of the humid fraction of the second combustion gas flow is condensed into water, which is separated from the rest of the gas mixture of water and carbon dioxide. 12. The method according to claim 11, wherein the cooler/condenser-module cools the combustion gas down to a temperature of between 65° C.-75° C. 13. The method according to claim 11, further comprising the steps of: condensing in the cooler/condenser, at least partly, the humid fraction of the combustion gas into liquid phase, andseparating the liquid phase from the combustion gas. 14. The method according to claim 11, wherein the cooler/condenser is designed to minimize the humid fraction of the combustion gas, and the heater is designed to increase the temperature of the recirculated first combustion gas flow, such that the maximum temperature after the compression of the recirculated first combustion gas flow is reached so that a predetermined maximum pressure is reached for maximum gas turbine cycle efficiency.