Abstract: The “imbalance index value” representing the magnitude of the difference among the cylinder-by-cylinder air-fuel ratios (imbalance of air-fuel ratios among cylinders) is acquired based on the output value of the air-fuel ratio sensor disposed above the catalyst. The execution of the emission reduction control is “limited” when the magnitude of the imbalance of air-fuel ratios among cylinders represented by the imbalance index value is the first degree or more, and less than the second degree which is larger than the first degree, and is “prohibited” when it is the second degree or more. As the emission reduction control, a purge control, an EGR control, an Al incremental control, a cold VVT control, a catalyst warm-up delay angle control, an SCV control, and the like can be exemplified. Misfire due to the execution of emission reduction control are suppressed, when the imbalance of air-fuel ratios among cylinders occurs.

Abstract: The invention makes use of an exhaust gas catalyst, comprising an active component comprising at least one type of metal from noble metals and transition metals; NOx-absorbing material for absorbing and releasing nitrogen oxides according to the surrounding nitrogen oxide concentration; and compounds represented by A2O2SO4 and/or A2O2S (A is a rare earth element).

Abstract: The present invention relates to a method for controlling air injection into the exhaust of an internal-combustion engine running on a cycle during which the expansion phase (D) thereof has a greater stroke than the compression phase (C) thereof and comprising at least one cylinder (10) with a combustion chamber (18), a piston (16), at least one intake means (24) with a valve (28) associated with an intake pipe (26), at least one exhaust means (30) with a valve (34) associated with an exhaust pipe (32), fresh air injection means (48) at the exhaust and an exhaust line (40) comprising at least one exhaust gas depollution means (46).

Abstract: Described herein are various embodiments of an apparatus and system for trapping debris and arresting sparks that overcomes at least some shortcomings of the prior art approaches. According to one embodiment, an apparatus is disclosed for mitigating failure of an exhaust after-treatment component in an internal combustion engine system capable of generating an exhaust gas stream. The apparatus includes a housing that includes an exhaust inlet, exhaust outlet, and exhaust flow channel positioned between the exhaust inlet and outlet. Also, the apparatus includes a tubular-shaped mesh screen positioned substantially entirely within the exhaust flow channel. The mesh screen includes a closed end positioned proximate the exhaust inlet of the housing and an opposing open end positioned proximate the exhaust outlet of the housing. The mesh screen is configured to capture failed exhaust after-treatment component particles within the exhaust gas stream.

Abstract: A mass damper method includes providing an electroactive polymer (7) and using the electroactive polymer (7) to manufacture a mass damper (6). The mass damper (6) for damping a vibrating system of a motor vehicle includes at least one of a damping body (10) forming a countervibrating mass with a damping spring (11) and a springy damping body (10) forming the countervibrating mass. The damping body (10) is indirectly or directly coupled with the vibrating system. The springy damping body (10) or the damping spring (11) includes an electroactive polymer (7). A motor vehicle exhaust system of an internal combustion engine is provided including an exhaust gas line (3) with an exhaust pipe (4), an exhaust gas-treating device (5) integrated in the exhaust pipe and the mass damper (6) coupled with the exhaust gas line.

Abstract: Apparatus and method for processing a process fluid at a remote location, with the apparatus including a pump located at a first location and configured to provide a pressurized working fluid. The apparatus also includes an umbilical coupled to the pump such that the umbilical receives the pressurized working fluid from the pump and transports the pressurized working fluid therefrom. The apparatus further includes a hydraulic turbine disposed at the remote location and coupled to the umbilical such that the hydraulic turbine receives the pressurized working fluid from the umbilical. The apparatus additionally includes one or more shaft energy conversion devices operatively coupled to the hydraulic turbine and disposed at the remote location.

Abstract: Systems, apparatus and methods of compressed air energy storage and electrical power generation are provided. In one embodiment, an apparatus is provided having a magnetic piston within a cylinder and an air chamber at each end of the piston; an electromagnetic coil is operable with the piston to convert an input of electrical power to a first reciprocating movement of the piston sufficient to generate compressed air in the chambers for storage in a compressed air storage reservoir; and the electromagnetic coil is operable with the piston to convert a second reciprocating movement of the piston to an output of electrical power connectable to a power grid, with the second reciprocating movement of the piston generated by bursts of the compressed air from the storage reservoir introduced into the chambers.

Abstract: A pump for use in pumping hydraulic well control fluid expelled from a control device of a well, comprises means for accumulating such hydraulic well control fluid and means for using the pressure of hydraulic fluid supplied to the well to pump accumulated hydraulic well control fluid into a production flowline of the well.

Abstract: A hydrostatic drive, in particular a fan drive, with a variable displacement pump is configured to drive at least one hydraulic motor. The variable displacement pump is activated via a pressure regulating valve and a following directional valve predetermining the feed direction, via which valves the control spaces of an actuating cylinder can be acted upon with a control pressure difference. The variable displacement pump is prestressed into a basic position in which the feed volume flow is maximum.

Abstract: An electrohydraulic steering system, in particular for mobile working machines having a pressure medium supply system from which a first connection, which acts in a first steering direction, can be supplied via a first feed line, while a second connection, which acts in a second steering direction, can be supplied via a second feed line. In this case, the two feed lines and also a first return line from the first connection to a tank and a second return line from the second connection to the tank are controlled via in each case at least two parallel valves. Therefore, in the event of failure of one of the valves, the at least one valve which is connected in parallel can take over control of the corresponding feed lines or the corresponding return line.

Abstract: An active material-based device for and related method of clamping and releasing objects. Broadly, the device includes an elongated piece of active material, such as a wire, having an actuation temperature and arranged to form a sleeve defining a volume of space. When the active material reaches the actuation temperature the material changes, which causes one or more dimensions of the volume of space to change. An object located within the sleeve experiences either a clamping or releasing force resulting from the change in the volume of space.

Abstract: An SMA actuation apparatus comprises: an SMA actuator arranged to drive movement of a movable element; a current supply supplying a drive current; a detection circuit detecting a measure of the resistance of the SMA actuator; and a control unit operative to generate a closed-loop control signal supplied to current supply for controlling the power of the drive current to drive the resistance of the SMA actuator to a target value. The control unit derives: an estimate of a characteristic temperature of the SMA actuation apparatus on the basis of the supplied power, using a thermal model; and a resistance offset on the basis thereof. The closed-loop control signal is generated on the basis of the error between the measure of the resistance of the SMA actuator and the target value of the resistance of the SMA actuator, adjusted by the resistance offset to compensate for variations in resistance.

Abstract: Provided is a driving module, including: a tubular or cylindrical body to be driven (4); a cylindrical support (5) for housing the body to be driven therein; a pair of plate spring members (6, 7) for elastically holding the body to be driven so that the body to be driven is movable in a fixed direction relative to the support; and driving means (10) for driving the body to be driven against a recovering force of the plate spring members, in which the plate spring members includes the first plate spring member (6) positioned on a side which does not receive a force generated by the driving means and the second plate spring member (7) positioned on the opposite side of the body to be driven from the first plate spring member, a spring constant of the first plate spring member being larger than that of the second spring member.

Abstract: Disclosed is a motor-pump assembly (1) for a brake actuating device of a motor vehicle brake system with a pneumatic brake booster. An electric motor (3) drives a double diaphragm pump (2) with two working diaphragms (4) which are located opposite one another. Air expelled from the working spaces (7) is directed into an interior space (22) surrounding a crank drive (8) of the pump housing (5). An air outlet unit (23, 53) has a filter housing (32, 54), a filter (33, 59), an air outlet cover (34, 56), a valve holding element (38, 70) and a valve body (31). A partition wall (37, 55) deflects the air emerging from the interior space (22) in the air outlet unit (23, 53 between the filter housing (32, 54) and the air outlet cover (34, 56), with an integrally molded valve holding element (38, 70).

Abstract: Disclosed is a hydraulic brake booster. A relative movement structure of a control plunger and an output shaft is modified in such a manner that the output shaft operates in the control plunger, thereby reducing the overall length of the booster and the manufacturing cost. An inner circumferential surface of a guide of the control plunger does not make contact with an outer circumferential surface of the output shaft, so that the vibration and the impact caused by the contact between the control plunger and the output shaft are not delivered, thereby improving brake pedal feeling. The control plunger includes a guide having a groove, and an inner diameter of the guide is greater than an outer diameter of the output shaft. The control plunger and the output shaft perform relative movement in the overlap state therebetween, thereby reducing the overall length of the booster and the manufacturing cost.

Abstract: An engine assembly comprising a cylinder head, turbocharger in fluid communication with the cylinder head and exhaust conduit in fluid communication with the turbocharger and method of making the assembly using a single human assembler includes: mounting the turbine to the cylinder head; using a first assembly aid to form a slidable joint between the exhaust conduit and head; using a second assembly aid to form a movable joint between the turbine and exhaust conduit and align the turbine outlet flange and exhaust conduit inlet flange; using a third assembly aid to pilotingly engage the flanges; disposing a clamp about the turbine outlet flange and the exhaust conduit inlet flange; tightening the second assembly aid sufficiently to form an immovable joint; tightening the clamp to form a sealed joint between the flanges; and tightening the first assembly aid to form a fixed joint.

Abstract: A non-fuel combusting air turbine assembly suitable as an auxiliary or primary power propulsion system for a vehicle. The system includes an air turbine engine powered by a compressor mechanism to increase the potential energy that can be harnessed by the turbines, having a noise reducing air intake section for delivering air to the compressor. Additionally, the system includes a turbine mechanism comprising plural sets of stationary vanes and rotating vanes, preferably arranged alternatively; and a battery rechargeable by a generator operable by the rotating turbine vanes.

Abstract: A method for producing power using geothermal liquid produced from geothermal fluid extracted from a geothermal well includes: a) providing a geothermal power plant for producing power indirectly using heat contained in geothermal liquid supplied thereto and produced from geothermal fluid extracted from a geothermal well; and b) providing an indirect heat exchanger means for indirectly heating a solution using heat contained in heat depleted geothermal liquid exiting the geothermal power plant and indirectly transferring heat to the solution producing a heated solution that produces hydrogen for use in producing power.

Abstract: A solar thermal power plant is provided. The plant includes a steam-electric power plant associated with a steam generation system operationally connected thereto for providing heat to drive its operation, a solar collection system designed to heat thermal fluid and is in communication with the steam-electric power plant to provide heat thereto for driving its operation, and a non-solar power plant including a power generation unit and a waste heat recovery unit. The solar thermal power plant further includes a controller configured to selectively operationally connect the solar collection system and the waste heat recovery unit to the steam-electric power plant to provide heat thereto.

Abstract: A solar thermal power plant is provided. The solar thermal power plant includes a thermal-electric power plant and a solar collection system in communication therewith to provide heat thereto for driving its operation and being designed to facilitate capture of thermal energy of incident solar radiation by a thermal transfer fluid flowing therethrough for providing the heat. The solar collection system includes one or more solar collectors configured for the capture. The solar collection system further includes at least one dual-purpose pipe configured for carrying heated thermal transfer fluid to the thermal-electric power plant, the dual-purpose pipe including a supply chamber for carrying the thermal transfer fluid therethrough, and at least one storage element in thermal communication with and in fluid isolation from the supply chamber, and being configured for storing thermal energy for providing heat for driving operation of the thermal-electric power plant.

Abstract: A method for storing heat from a solar collector CSTC in Concentrating Solar Power plants and delivering the heat to the power plant PP when needed. The method uses a compressed gas such as carbon dioxide or air as a heat transfer medium in the collectors CSTC and transferring the heat by depositing it on a bed of heat-resistant solids and later, recovering the heat by a second circuit of the same compressed gas. The storage system HSS is designed to allow the heat to be recovered at a high efficiency with practically no reduction in temperature. Unlike liquid heat transfer media, our storage method itself can operate at very high temperatures, up to 3000° F., a capability which can lead to greater efficiency.

Abstract: A heat engine using solar energy is disclosed. The heat engine in accordance with an embodiment of the present invention includes a first body, a second body and a solar concentrator, and can have highly efficient thermal cycles by allowing a first piston assembly and a second piston assembly to reciprocate opposite directions with respect to each other inside a first cylinder and a second cylinder, respectively, as first operating gas and fourth operating gas or second operating gas and third operating gas thermally expand alternately.

Abstract: A thermally isolated counter flowing heat exchanger comprising two isolated fluids having different energy levels flowing in contained systems separated by fluid heat trap passages and utilizing gates that control flow into different cells based on temperature. A system for transferring and storing thermal energy comprising a refrigerant circulating in a tank in a vortex such that when the vortex flow of the refrigerant is in contact with multiple spaced tubing located inside the tank, energy is transferred between the refrigerant and a fluid flowing inside the tubing. A system for generating energy comprising a hot regenerator and a cold regenerator, each thermally isolated and connected to counter cycling hot expansion pistons that utilize compression of exhausting hot gas as it flows into the cold regeneration area to create a suction effect on the exhausting hot gas that adds power to the compression stroke of the piston to provide energy.

Abstract: Provided herein are methods and systems for sequestering carbon dioxide from a multi-component gaseous stream, such as flue gas from natural gas-burning power plant to produce a protonated carbonate. Also provided herein are methods and systems for electrochemically producing proton-removing agents to form a deprotonated carbonate from the protonated carbonate. The electrochemical process may consume less energy than the amount of energy generated during production of the multi-component gaseous stream.

Abstract: A power regeneration system for use with an information handling system is disclosed. The power regeneration system may include a thermosiphon in thermal communication with a heated component of the information handling system, a turbine, a condenser, and a fluid flow loop. The thermosiphon may be configured to convert a cooling fluid from a liquid to a gaseous state as the cooling fluid absorbs heat from the heated component of the information handling system. The turbine may be configured to extract energy from the cooling fluid in the gaseous state after it leaves the thermosiphon. The condenser may be configured to remove thermal energy from the cooling fluid after it leaves the turbine, the condenser fluid converting the cooling fluid from a gaseous state to a liquid state as thermal energy is removed. The fluid flow loop may connect the thermosiphon, the turbine, and the condenser in order so that the cooling fluid flows in a closed loop through the power regeneration system.

Abstract: A non-polluting, closed-cycle condensing heat engine and operating method is provided for propelling road vehicles at high efficiencies and high power densities by using a phase-changing working fluid having a critical temperature close to the natural ambient temperature of the surrounding atmosphere and shifting the high temperature heat reservoir downward by several hundred degrees by creating an artificial low temperature heat reservoir below ambient temperature by evaporating water.

Abstract: Various embodiments of a converter for use in a combustion engine having a discharge conduit for discharging exhaust combustion gases are disclosed. In one exemplary embodiment, the converter may include a heating chamber being in thermal contact with the discharge conduit and defining a hydraulic channel through which a fluid passes. The converter may also include an inlet port disposed in the heating chamber for receiving the fluid into the heating chamber, and an outlet port disposed in the heating chamber for discharging the fluid from the heating chamber. The heat energy from the exhaust combustion gases is transferred to the fluid while the fluid passes through the hydraulic channel.

Abstract: An electronic probe housing having two speed pick up devices automatically sends electric signals to an electronic governor which causes the RPM of the steam turbine to increase, decrease or remain constant, in conjunction with one or more additional speed pick up devices in the same probe housing which uses a logical array of electro-hydraulic solenoid valves to control an automatic shut off system which cuts off the steam supply to the steam turbine.

Abstract: A method and corresponding apparatus for separation of carbon dioxide from an exhaust gas of a fossil-fired power are provided. In an absorption process, the exhaust gas containing carbon dioxide is brought into contact with an absorption medium so that the absorption medium is laden with carbon dioxide. In a desorption process, vapor from a water/steam circuit of the fossil-fired power plant is heated, wherein a laden absorption medium is regenerated. In a subsequent expansion process, the regenerated absorption medium is expanded so that a vapor and an expanded absorption medium are formed, wherein the vapor is recirculated into the desorption process. The laden absorption medium is divided into a first part stream and a second part stream. Only the second part stream is brought into heat-exchanging contact with the expanded absorption medium. The first and second part streams are supplied to the desorption process at different process stages.

Abstract: This system for supplying a turbine with liquid fuel comprises a liquid fuel inlet (3), a piping assembly (4) connecting the inlet to the turbine, and draining means for draining at least a portion of the said piping assembly. The draining means comprise water inlet means (9) and a system of controllable valves suitable for injecting water into at least one of the said portions of the piping assembly.

Abstract: A fuel injector is provided and includes an outer body, a converging tubular body including a converging section, defining a converging annular passage therein and being disposed within the outer body to define an outer annular passage between an interior surface of the outer body and an exterior surface of the converging tubular body, the annular passages each being receptive of a fluid at respective inlets thereof such that the fluid is directed to flow toward respective outlets thereof and a fuel line to deliver fuel through at least the converging tubular body at the converging section to the converging annular passage in a substantially tangential direction relative to a circumferential curvature of the converging tubular body.

Abstract: A coordinated air-fuel controller and associated method provide a fuel controller, a combustion air controller and a steady-state air versus fuel model. The fuel controller generates a fuel control output signal and the combustion air controller generates a combustion air control output signal. The fuel controller determines a preliminary fuel control signal based on at least one of first and second loop control signals, and determines the fuel control output signal based on the preliminary fuel control signal. The steady-state air versus fuel model processes the preliminary fuel control signal to determine an expected steady-state combustion air control signal. The combustion air controller determines a preliminary combustion air control signal based on at least one of a third loop control signal and a fourth loop control signal, and determines the combustion air control output signal based on the preliminary combustion air control signal and the expected steady-state combustion air control signal.

Abstract: The present inventions include a boundary layer ejector fluidically connecting boundary layer bleed slots from an external surface of an aircraft to reduce aircraft/nacelle/pylon drag, reduce jet noise and decrease thrust specific fuel consumption. In one embodiment a boundary layer withdrawn through the boundary layer bleed slots is entrained with an exhaust flow of a gas turbine engine. In another embodiment a boundary layer withdrawn through the boundary layer bleed slots is entrained with a flow stream internal to the gas turbine engine, such as a fan stream of a turbofan. A moveable shroud can be used to open and close a passage of an ejector which can be used to assist in withdrawing a boundary layer or entrain an ambient air. A lobed mixer can be used in some embodiments to effect mixing between the boundary layer and a primary fluid of the ejector.

Abstract: This ventilation system (1), notably for a gas turbine, comprises at least one fan (2) opening into an air extraction duct (5). It comprises at least one device (6) for varying the pressure drop in the air extraction duct (5), comprising a means (8) of regulating the air flow rate in the air extraction duct (5).

Abstract: The sports fan cooling station is specifically designed for the sports fan(s) who enjoys outdoor sporting events. This cooling station utilizes the thermoelectric cooler peltier effect and AC power to cool individuals and beverages. The cooling station has a cooling hood that blocks the sunlight and cools the sports fan in a high heat stress environment. It also has a beverage cooler that cools beverages for the sports fan. In addition, the cooling station can be connected to multiple cooling hoods which can cool multiple sports fans at the same time. The cooling station is compact and portable. With this cooling station, sports fans can enjoy a sporting event and not worry about suffering from heat stress caused by hot weather.

Abstract: A method for operating a cryostorage device (100), especially for biological samples, is described which comprises a sample carrier (10) to receive at least one sample (11) and a data storage (20), wherein data are inductively transmitted from the data storage device (20) into a wireless transmission channel (40) and/or conversely using a resonant circuit (30) connected to the data storage device (20).

Abstract: The present invention relates to a supercooling system which can supply heat to a stored object or generate heat according to a sensed temperature to maintain the stored object in a supercooled state.

Abstract: A pool heating system is disclosed. The pool heating system includes, in some embodiments, an immersed condenser coil. In some embodiments, the immersed condenser coil is immersed in pool of water receiving hot refrigerant gas at high pressure from an outdoor unit, transferring heat to water in the pool, condensing the gas and transmitting condensed refrigerant to the outdoor unit. The system also includes an outdoor unit. In some embodiments, the outdoor unit includes a compressor, an expansion valve, an evaporator, and a fan.

Abstract: A cold tray for a container may have an interior. The cold tray may include a cold tray housing mountable within the container interior. A refrigerant may be mounted to the cold tray housing. An air flow source may be fluidly connectable to the cold tray housing and may draw air from the container interior into the cold tray housing such that the air passes over the refrigerant and is discharged back into the container interior.

Abstract: The amount of supply air used by an HVAC system, and hence the amount of energy used for heating and cooling, while maintaining desirable air quality and composition, is reduced by removing unwanted gases, such as carbon dioxide, using scrubbers or other devices that separate these gases from the circulating air. Optionally, the air can be further improved with injection of concentrated oxygen. While in a normal HVAC system frequent replacement of the building air is performed, scrubbing of CO2 and other unwanted gases, with or without additional oxygen, would achieve the same goal, but with less frequent air replacement and therefore lower thermal load on the HVAC system.

Abstract: A heat dissipation system includes a cooling device, a condenser, a vapor conveying duct and a cooling liquid conveying duct. The cooling device includes a housing, and an orifice plate dividing an inner space of the housing into a liquid supply chamber and an evaporation chamber proximate to the heat source, and formed with multiple micro orifices each having a diameter ranging from 5 to 1000 micrometers. The condenser includes a fluid inlet, a condensing chamber and a fluid outlet. The vapor conveying duct connects a vapor outlet of the housing and the fluid inlet of the condenser. The cooling liquid conveying duct connects a cooling liquid inlet of the housing and a fluid outlet of the condenser.

Abstract: A coolant adduction assembly for a climate control system of a vehicle, characterized in that it comprises a joint and a tube inserted into said joint, wherein said pipe and joint comprise a thermoplastic material and are rigidly connected by means of a laser welding.

Abstract: A refrigeration appliance includes a carcass having walls to define an interior with an open front side. One of the walls extends from the front side of the carcass in a depth direction and is formed with at least one recess. A translucent pane seals the at least one recess and is at least locally clear. At least one light-emitting diode module is accommodated in the at least one recess and produces a light cone which lies completely within the interior.

Abstract: A heat exchanger 21 is provided with a metal tube 47 that has a support member 55 inhibiting deformation in the thickness direction in a fluid flow channel 53, and a multiple-hole metal tube 45 that is stacked on one side of the metal tube 47 in the thickness direction and has an opposing surface disposed opposite an outer surface 61 on the one side of the metal tube 47 and joined by at least part thereof to the outer surface 61 on the one side.

Abstract: An indoor unit of an air conditioner is provided. A width of the indoor unit of the air conditioner may be varied based on whether or not the indoor unit of the air conditioner is operated.

Abstract: An improved method is provided for removing contaminants from a hydrocarbon stream, such as a stream of raw natural gas. The contaminated hydrocarbon stream is passed through a first adsorbent bed containing molecular sieves to adsorb contaminants on the molecular sieves, thereby removing at least some of the contaminants from the hydrocarbon stream. The contaminated hydrocarbon stream may optionally be passed through a second adsorbent bed containing a desiccant material other than molecular sieves. The molecular sieves are regenerated using a wet regeneration process in which both the water content and temperature of the regeneration fluid stream are staged.

Abstract: A method and apparatus for processing natural gas composed of various hydrocarbon components for transportation of the natural gas to a demand side without separation of the hydrocarbon components, such that the natural gas can be used by consumers after being separated into the hydrocarbon components according to the needs of the demand side. The apparatus includes a storage tank and a hydrocarbon liquefied gas mixture accommodated in the storage tank. The mixture has hydrocarbon components composed of methane, ethane, propane and butane, and is produced by liquefying raw natural gas without changing the relative ratio of methane, ethane, propane and butane in the raw natural gas immediately after extraction from the gas well. The method and apparatus can be applied to floating marine structures.

Abstract: A method of controlling one or more refrigerant compressors (12) for one or more gaseous streams (10) at a normal operating temperature. At least one refrigerant compressor (12) has a vapour recirculation line (30). A compressor feed stream (10a) is provided from a combination of a vapour recirculation stream (30) from the vapour recirculation line (30) and an at least partly evaporated refrigerant stream (8). The compressor feed stream (10a) is passed through a suction drum (11) to provide a compressor gaseous stream (10), which is passed through the refrigerant compressor (s) (12). The inlet temperature T1 of the compressor gaseous stream (10) is determined, and cooling of a refrigerant stream is controlled in response to temperature T1 to provide the compressor gaseous stream (10) at the normal operating temperature of at least one refrigerant compressor (12).

Abstract: A method for producing a sterile cryogenic fluid from a cryogenic gas by sterilizing the cryogenic gas and using a heat exchanger to liquefy the sterile cryogenic stream. The discharge rate of the sterile cryogenic fluid is controlled by sizing the discharge orifice and setting a predetermined pressure of the sterile cryogenic fluid.

Abstract: The invention relates to a method for the separation of a hydrocarbon-rich, nitrogen-containing feed fraction (1, 101), preferably natural gas, wherein the feed fraction (1, 101) is at least in part liquefied (E1, E2) and divided by rectification (T1) into a nitrogen-enriched fraction (14, 110) and a hydrocarbon-rich, nitrogen-depleted fraction (11, 111) and wherein, in the upper region of the rectification (T1), a nitrogen-enriched stream (14) is taken off, cooled (E3) and applied (20) at least in part to the rectification (T1) as reflux and/or the nitrogen-enriched fraction (110) is cooled and partially condensed (E3), applied at least in part to the rectification (T1) as reflux (115) and the remaining stream (116) of the nitrogen-enriched fraction (110) is subjected to a double-column process (T3).