Combination of supercritical wet combustion and compressed air energy storage

Claim 2

A combination of pressurized combustion and compressed air energy storage in which air is compressed to combustion pressure by means of a compression train comprising a plurality of stages, combustion heat is transferred at combustion pressure to boiling feedwater, cooled flue gas is reheated and expanded through turbines which drive the compressor stages, the compression train having capacity in excess of that required for combustion during off-peak periods, the excess compressed air during such periods being charged to a storage cavern.

Claim 3

A process as in claim 1 in which the compressed air charged to the storage cavern during off-peak periods is withdrawn from the storage cavern during peak periods and utilized as combustion air in the pressurized combustion.

Claim 4

A process as in claim 2 in which the air withdrawn during peak periods is recompressed to combustion pressure by the last stage of the compression train, earlier stages being disconnected from the turbines which drove them during off-peak periods, the power of the disconnected turbines being redirected to generators which the redirected power to peak load electricity.

Claim 5

A process as in claim 2 in which stages of the compression train, excepting the last stage, have excess capacity to charge the storage cavern and the air withdrawn during peak periods is compressed to combustion pressure by the last two stages of the train, earlier stages being disconnected from the turbines which drove them during off-peak periods, the power of the disconnected turbines being redirected to generators which convert the redirected power to peak load electricity.

Claim 6

A process as in claim 2 in which the air compressed to combustion pressure, which during off-peak periods is in excess of combustion requirements, is, further compressed by a booster compressor to a storage pressure higher than combustion pressure and, during peak periods, withdrawn from the storage cavern and utilized as combustion air, the compressors of the compression train and the booster compressor being disconnected from the turbines which drove them during off-peak periods, the power of the disconnected turbines being redirected to generators which convert the redirected power to peak load electricity.

Claim 7

A process as in claim 3 in which the stages of the compression train, excepting the last stage, are divided into parallel trains, the compressors of one of the parallel trains being disconnected, during peak periods, from the turbines which drove them during off-peak periods, the power of the disconnected turbines being redirected to generators which convert the redirected power to peak load electricity.

Claim 8

A process as in claim 4 in which the stages of the compression train, excepting the last two stages, are divided into parallel trains, the compressors of one of the parallel trains being disconnected, during peak periods, from the turbines which drove them during off-peak periods, the power of the disconnected turbines being redirected to generators which convert the redirected power to peak load electricity.

Claim 9

A process as in claim 5 in which the compression train is divided into parallel trains, the compressors of one of the parallel trains and the booster compressor from the turbines which drove them during off-peak periods being disconnected, during peak periods, the power of the disconnected turbines being redirected to generators which convert the redirected power to peak load electricity.

Claim 10

A combination of a pressurized combustion and compressed gas energy storage in which flue gas from the combustion is, during off-peak periods, cooled and cleaned under essentially combustion pressure and charged to a storage cavern from which, during peak periods, it is withdrawn, heated and expanded through turbines driving peak load generators.

Claim 11

A combination of a pressurized combustion and compressed gas energy storage in which flue gas from the combustion is, during off-peak periods, cooled and cleaned under essentially combustion pressure and charged to a storage cavern from which, during peak periods, it is withdrawn, heated and expanded through turbines driving peak load generators.

Claim 12

A process as in claim 9 in which a mixture of the cooled and cleaned flue gas and air compressed by combustion air compressors, in excess of combustion requirements, is charged to the storage cavern from which, during peak periods, it is withdrawn, heated and expanded through turbines driving peak load generators.

Claim 13

An energy storage process in which compressed air is charged, during off-peak periods, to a storage cavern from which, during peak periods, it is withdrawn and utilized as combustion air in a pressurized combustion to which solid fuel is charged as an aqueous slurry containing alkali, in an amount at least the chemical equivalent of the sulfur in the fuel as alkali sulfate, combustion temperature is controlled below a maximum of 1600 degrees F. by the injection of water and combustion products, after separation therefrom of solid products by a gas-solids separating device, are expanded through turbines driving generators which produce peak load electricity.

Claim 14

An energy storage process in which compressed air is charged, during off-peak periods, to a storage cavern from which, during peak periods, it is withdrawn and utilized as combustion air in a pressurized combustion to which solid fuel is charged as an aqueous slurry containing alkali, in an amount at least the chemical equivalent of the sulfur in the fuel as alkali sulfate, combustion temperature is controlled below a maximum of 1600 degrees F. by the injection of water and combustion products, after separation therefrom of solid products by a gas-solids separating device, are expanded through turbines driving generators which produce peak load electricity.

Claim 15

A process as in claim 11 in which combustion products, after separation therefrom of solid products, are cooled below their dewpoint, forming an aqueous condensate containing solid products not separated by the gas-solids separating device and a purified flue gas-steam mixture which is expanded through turbines driving generators which produce peak load electricity.