Method and device for generating electrical energy

A device for generating electrical energy comprising:

• a combined system comprising a power plant (18) and a cryogenic air separation unit (7), said cryogenic air separation unit (7) comprising a main air compressor (3, 4, 5;
• 30) for compressing an air feed stream (1), a main heat exchanger for cooling a compressed air feed stream, a distillation column system comprising a high-pressure column and a low-pressure column, wherein pressures within said high-pressure column are higher than any pressures within the low-pressure column, and means for introducing a cooled air feed stream into said distillation column system,
• means for introducing a first oxygen-enriched product stream (17) from said distillation column system into said power plant (18),
• means for introducing a cryogenic liquid (21, 21a), which is formed by a first process fluid (16, 19) of the distillation column system, into a liquid tank (22) during a first operating mode,
• means for removing the cryogenic liquid (23) from said liquid tank (22) and introducing the cryogenic liquid into said distillation column system during a second operating mode,
• means for heating (14) a second process fluid (24) of said distillation column system to a high temperature prior to any active depressurization thereof, wherein said second process fluid (24) is a nitrogen-enriched product stream removed from said high pressure column,
• a hot expansion turbine (26) for active depressurization of heated second process fluid during the second operating mode,
• means for converting (28) mechanical energy generated in said hot expansion turbine (26) into electrical energy (29) during the second operating mode,
• means for removing the nitrogen-enriched product stream from the high-pressure column as the second process fluid (24) of said distillation column system and means for supplying the nitrogen-enriched product stream to said means for heating (14) and to said hot expansion turbine (26) during the second operating mode.

A device for generating electrical energy comprising:

• a combined system comprising a power plant (18) and a cryogenic air separation unit (7), said cryogenic air separation unit (7) comprising a main air compressor (3, 4, 5;
• 30) for compressing an air feed stream (1), a main heat exchanger for cooling a compressed air feed stream, a distillation column system comprising a high-pressure column and a low-pressure column, wherein pressures within said high-pressure column are higher than any pressures within the low-pressure column, and means for introducing a cooled air feed stream into said distillation column system,
• a line for introducing a first oxygen-enriched product stream (17) from said distillation column system into said power plant (18),
• a line for introducing a cryogenic liquid (21, 21a), which is formed by a first process fluid (16, 19) of the distillation column system, into a liquid tank (22) during a first operating mode,
• a line for removing the cryogenic liquid (23) from said liquid tank (22) and introducing the cryogenic liquid into said distillation column system during a second operating mode,
• a nitrogen heater (14) for heating a second process fluid (24) of said distillation column system to a high temperature, prior to any active depressurization thereof, wherein said second process fluid (24) is a nitrogen-enriched product stream removed from said high pressure column,
• a hot expansion turbine (26) for active depressurization of heated second process fluid during the second operating mode,
• a generator for converting (28) mechanical energy generated in said hot expansion turbine (26) into electrical energy (29) during the second operating mode,
• a line for removing the nitrogen-enriched product stream from the high-pressure column as the second process fluid (24) of said distillation column system and a line for supplying the nitrogen-enriched product stream to said nitrogen heater (14) and to said hot expansion turbine (26) during the second operating mode.