Method and plant for generating a synthesis gas which consists mainly of carbon monoxide and hydrogen and has been freed of acid gases, proceeding from a hydrocarbonaceous fuel, and air and steam, wherein low-temperature fractionation separates air into an oxygen stream, a tail gas stream and a nitrogen stream, wherein the tail gas stream and the nitrogen stream are at ambient temperature and the nitrogen stream is at elevated pressure, wherein the hydrocarbonaceous fuel, having been mixed with the oxygen stream and steam at elevated temperature and elevated pressure, is converted to a synthesis gas by a method known to those skilled in the art, and wherein acid gas is subsequently separated therefrom by low-temperature absorption in an absorption column, wherein the nitrogen stream generated in the fractionation of air is passed through and simultaneously cooled in an expansion turbine and then used to cool either the absorbent or the coolant circulating in the coolant circuit of the compression refrigeration plant.

Method and plant for generation of synthesis gas, comprising the steps of air fractionation to give oxygen, nitrogen and tail gas, gasification of a hydrocarbonaceous fuel to give crude synthesis gas and cleaning of the crude synthesis gas by removal of acid gas by means of cryogenic absorption, wherein the absorbent is cooled by means of a compression coolant circuit and the cooling water used is cooled by evaporative cooling by means of the tail gas obtained in the air fractionation.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

A chiller can be configured as a chiller for a gasification system or other type of system or plant. In some embodiments, the chiller can be configured to utilize a single heat source, such as low grade waste heat in the form of hot water, and/or low pressure steam to drive one or more absorption-based chillers to cool inlet air to one or more adsorbers of a pre-purification unit (PPU). In the event of the detection of an undesired impurity spike (e.g. carbon dioxide spike, etc.) an additional amount of heat source can be withdrawn from the gasification system to increase the level of cooling the absorption chiller can provide to improve the removal of impurities. An automated control loop can be utilized in some embodiments. The control loop can be configured to check for an impurity concentration and adjust operations accordingly.

Method and plant for generation of synthesis gas, comprising the steps of air fractionation to give oxygen, nitrogen and tail gas, gasification of a hydrocarbonaceous fuel to give crude synthesis gas and cleaning of the crude synthesis gas by removal of acid gas by means of cryogenic absorption, wherein the absorbent is cooled by means of a compression coolant circuit and the cooling water used is cooled by evaporative cooling by means of the tail gas obtained in the air fractionation.

Method and plant for generating a synthesis gas which consists mainly of carbon monoxide and hydrogen and has been freed of acid gases, proceeding from a hydrocarbonaceous fuel, and air and steam, wherein low-temperature fractionation separates air into an oxygen stream, a tail gas stream and a nitrogen stream, wherein the tail gas stream and the nitrogen stream are at ambient temperature and the nitrogen stream is at elevated pressure, wherein the hydrocarbonaceous fuel, having been mixed with the oxygen stream and steam at elevated temperature and elevated pressure, is converted to a synthesis gas by a method known to those skilled in the art, and wherein acid gas is subsequently separated therefrom by low-temperature absorption in an absorption column, wherein the nitrogen stream generated in the fractionation of air is passed through and simultaneously cooled in an expansion turbine and then used to cool either the absorbent or the coolant circulating in the coolant circuit of the compression refrigeration plant.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.

A chiller can be configured as a chiller for a gasification system or other type of system or plant. In some embodiments, the chiller can be configured to utilize a single heat source, such as low grade waste heat in the form of hot water, and/or low pressure steam to drive one or more absorption-based chillers to cool inlet air to one or more adsorbers of a pre-purification unit (PPU). In the event of the detection of an undesired impurity spike (e.g. carbon dioxide spike, etc.) an additional amount of heat source can be withdrawn from the gasification system to increase the level of cooling the absorption chiller can provide to improve the removal of impurities. An automated control loop can be utilized in some embodiments. The control loop can be configured to check for an impurity concentration and adjust operations accordingly.

The present invention provides methods and system for power generation using a high efficiency combustor in combination with a CO.sub.2 circulating fluid. The methods and systems advantageously can make use of a low pressure ratio power turbine and an economizer heat exchanger in specific embodiments. Additional low grade heat from an external source can be used to provide part of an amount of heat needed for heating the recycle CO.sub.2 circulating fluid. Fuel derived CO.sub.2 can be captured and delivered at pipeline pressure. Other impurities can be captured.