Abstract: An inlet air cooling system used in a gas turbine for supplying power to a refrigerant compressor for compressing refrigerant in a natural gas liquefaction plant includes: an inlet air cooler for cooling inlet air of the gas turbine; chiller motors used for a chiller for cooling coolant supplied to the inlet air cooler; a first variable speed driver for supplying electric power to each of the one or more chiller motors; and an electric generator driven by the gas turbine, wherein the electric generator is electrically connected to the first variable speed driver, and electric power generated by the electric generator can be supplied to each of the chiller motors from the first variable speed driver without using a main power line of an electric power system, which enables efficient electric power supply to the motors via the variable speed driver.

Abstract: An inlet air cooling system used in a gas turbine for supplying power to a refrigerant compressor for compressing refrigerant in a natural gas liquefaction plant includes: an inlet air cooler for cooling inlet air of the gas turbine; chiller motors used for a chiller for cooling coolant supplied to the inlet air cooler; a first variable speed driver for supplying electric power to each of the one or more chiller motors; and an electric generator driven by the gas turbine, wherein the electric generator is electrically connected to the first variable speed driver, and electric power generated by the electric generator can be supplied to each of the chiller motors from the first variable speed driver without using a main power line of an electric power system, which enables efficient electric power supply to the motors via the variable speed driver.

Abstract: In a system for dehydrating carbon dioxide gas, the carbon dioxide gas is cooled by using a turbo expander (21), and the power extracted by the turbo expander from the carbon dioxide gas is used in the system for compressing the carbon dioxide gas. The cooled carbon dioxide gas is fed to a knock-out drum (22) to remove free water therefrom. The carbon dioxide gas from the separator is introduced to a secondary dehydration unit (11) and recompressed to the required pressure for carbon storage or for EOR operation.

Abstract: By using the power generated by an expander by an expansion of material gas, the outlet pressure of a compressor is increased, and a requirement on the cooling capacity of a cooler is reduced. The liquefaction system (1) for natural gas comprises a first expander (3) for generating power by using natural gas under pressure as material gas; a first cooling unit (11, 12) for cooling the material gas depressurized by expansion in the first expander; a distillation unit (15) for reducing or eliminating a heavy component in the material gas by distilling the material gas cooled by the first cooling unit; a first compressor (4) for compressing the material gas from which the heavy component was reduced or eliminated by the distillation unit by using power generated in the first expander; and a liquefaction unit (21) for liquefying the material gas compressed by the first compressor by exchanging heat with a refrigerant.

Abstract: By using the power generated by an expander by an expansion of material gas, the outlet pressure of a compressor is increased, and a requirement on the cooling capacity of a cooler is reduced.

Abstract: By using the power generated by an expander by an expansion of material gas, the outlet pressure of a compressor is increased, and a requirement on the cooling capacity of a cooler is reduced. The liquefaction system (1) for natural gas comprises a first expander (3) for generating power by using natural gas under pressure as material gas; a first cooling unit (11, 12) for cooling the material gas depressurized by expansion in the first expander; a distillation unit (15) for reducing or eliminating a heavy component in the material gas by distilling the material gas cooled by the first cooling unit; a first compressor (4) for compressing the material gas from which the heavy component was reduced or eliminated by the distillation unit by using power generated in the first expander; and a liquefaction unit (21) for liquefying the material gas compressed by the first compressor by exchanging heat with a refrigerant.

Abstract: By controlling an excessive rise in the temperature of the material gas that is introduced into the liquefaction unit following the compression by a compressor, the temperature of the material gas may be adjusted to the temperature level at the introduction point of the liquefaction unit. A system (1) for the liquefaction of natural gas, comprises a first expander (3) for expanding natural gas under pressure as material gas; a first cooling unit (10, 11, 12) for cooling the material gas; a distillation unit (15) for reducing or eliminating a heavy component in the material gas by distilling the material gas cooled by the first cooler; a first compressor (4) for receiving a top fraction of the material gas from which the heavy component was reduced or eliminated by the distillation unit; and a liquefaction unit (21) for liquefying a gas phase component separated from the compressed material gas compressed by the first compressor by exchanging heat with a refrigerant.

Abstract: Apparatus for compressing gaseous refrigerant for use in a refrigeration circuit of a liquefaction plant comprises a refrigeration circuit (1) and two compressors (10, 20) that are functionally connected to the refrigeration circuit. One of the compressors is provided with a double suction configuration, and the outlets and the inlets of the first and second compressors are connected at least partly in a mutually parallel flow configuration such that the refrigerant flow that leaves the refrigeration circuit from a plurality of outlets thereof is distributed between the two compressors before joining at the inlet of the refrigeration circuit.

Abstract: All sulfur compounds can be efficiently removed from natural gas that contains hydrogen sulfide and other sulfur compounds such as mercaptan without using physical absorption. The process comprises an absorption step of treating natural gas by means of a chemical absorption method using an amine-containing solution to mainly remove hydrogen sulfide and carbon dioxide, an adsorption step of flowing the natural gas from the absorption step through a packed bed of a molecular sieve to mainly remove mercaptan, a recovery step of recovering sulfur compounds by converting the hydrogen sulfide removed in the absorption step into sulfur by means of the Claus process, a regeneration step of desorbing the mercaptan adsorbed on the molecular sieve in the adsorption step using heated gas and a reaction step of converting the mercaptan in the regeneration exhaust gas exhausted from the regeneration step into hydrogen sulfide.

Abstract: All sulfur compounds can be efficiently removed from natural gas that contains hydrogen sulfide and other sulfur compounds such as mercaptan without using physical absorption. The process comprises an absorption step of treating natural gas by means of a chemical absorption method using an amine-containing solution to mainly remove hydrogen sulfide and carbon dioxide, an adsorption step of flowing the natural gas from the absorption step through a packed bed of a molecular sieve to mainly remove mercaptan, a recovery step of recovering sulfur compounds by converting the hydrogen sulfide removed in the absorption step into sulfur by means of the Claus process, a regeneration step of desorbing the mercaptan adsorbed on the molecular sieve in the adsorption step using heated gas and a reaction step of converting the mercaptan in the regeneration exhaust gas exhausted from the regeneration step into hydrogen sulfide.

Abstract: Provided is a method for liquefying natural gas which can be applied to LNG plants of a wide range of capacity and can produce LNG both efficiently and economically. Feed gas of natural gas or a non-liquefied component of recycle gas which is produced during a process of liquefying natural gas is liquefied by using a first refrigerant, for instant consisting of a C3 refrigerant, and a second refrigerant which is different from the first refrigerant, for instance consisting of a C2 refrigerant, in a stepwise fashion. The flow is then liquefied by a substantially isentropic expansion process. The non-liquefied component remaining from this expansion process is then pressurized by a compressor, and combined with the non-liquefied component of the natural gas for recycling the combined flow. The compressor is driven by power obtained from the substantially isentropic expansion process.

Abstract: In a compressor drive system for a natural gas liquefaction plant including a plurality of gas turbines each provided in an individual refrigeration cycle for pressurizing a different refrigerant, an electric motor is provided for each of the gas turbines so as to serve both as an auxiliary electric motor for generating a startup torque and as an AC generator, and the excess output power of the gas turbine is converted into electric power by this electric motor when the power requirement of the associated compressor is less than the power output of the gas turbine. Additionally, at least two of the gas turbines are of an identical make which is suitable for driving the compressor of one of the associated refrigeration cycles requiring a larger driving power.

Abstract: Provided is an improved refrigeration system for pre-cooling natural gas or cooling a mixed refrigerant for natural gas liquefaction in a propane refrigeration process widely used for the liquefaction of natural gas. The system comprises a plurality of plate-fin heat exchangers preferably arranged in a parallel relationship for passing a propane refrigerant as a vertical flow and pre-cooling natural gas or cooling a mixed refrigerant for liquefying natural gas, and a thermo siphon drum for the propane refrigerant consisting of a horizontally disposed, laterally elongated tank. Because the passages of the heat exchanger for the natural gas or the mixed refrigerant extend over their entire length in mutually separate relationship, even when the propane refrigerant, the natural gas or the mixed refrigerant is in both gas and liquid phases, a high efficiency of heat transfer can be attained, and the size of the heat exchanger can be reduced.

Abstract: Provided is a method for liquefying natural gas which can be readily adapted to LNG plants of all sizes without requiring expensive and special heat exchangers. The liquefaction of feed gas of natural gas and recycle natural gas is carried out with a single-component refrigerant or a mixed refrigerant in a high temperature stage, and with a substantially isentropic expansion in a low temperature stage, and a non-liquefied part of the recycle gas after the expansion step is pressurized with a compressor and recycled along with a recycle stream of non-liquefied par of the feed natural gas, the liquefied part by the refrigerant exchanging heat with the non-liquefied part stream produced from the substantially isentropic expansion, in a plate-fin heat exchanger or the like. The compressor is driven by the power obtained by the substantially isentropic expansion.