Method of production of liquefied natural gas and compressed natural gas at the gas distributing station and complex for its implementation

FIELD: oil and gas industry.

SUBSTANCE: method of production of liquefied natural gas and compressed natural gas at a gas distribution station (GDS), a non-volatile one, which simultaneously produces liquefied and compressed natural gas. Natural gas is taken from the main gas pipeline, divided into two streams: the first stream is directed to the liquefaction of natural gas and, at the same time, the second stream is directed to natural gas compression. The second stream is passed alternately through a second compressor and an air-cooling unit. Concurrently, the first liquefaction stream is filtered, purified in an adsorber, cooled in at least one heat exchanger and divided into two streams: process and production. The process flow is directed to the expander, with the generator of which the electrical connection of the first compressor engines is established, which is used when the production flow of the incoming first gas stream is liquefied, and the second compressor, which is used to compress the incoming second gas stream, as well as the fans of the air-cooling unit. The production stream is passed through the first compressor, cooled in an air-cooling unit, then it is additionally cooled in at least one heat exchanger and passed through a choke to produce a vapor-liquid mixture. Liquid phase is separated from it and, completing the production flow, directs it for download to the consumer of liquefied natural gas. Reverse flow is formed from the vapor phase, directed through the heat exchangers of the production stream, connecting with the expanded and low-temperature process stream leaving the expander. The complex for implementing the method includes two lines. The first natural gas supply line contains a filtration unit, an adsorber, a heat exchanger and is divided into a process, production and return line. The production line comprises a first compressor, an air-cooling unit, and at least one heat exchanger, a choke, a separator and is connected to a liquefied natural gas storage. The return line originates in the separator, passes through the heat exchangers of the production line and is connected at the outlet to the gas transmission grid. The process line contains an expander and is connected to the return line, at the same time the second natural gas supply line comprises a second compressor, an air-cooling unit and is connected to the consumers of compressed natural gas, and the expander generator is connected through electrical communication with the motors of the first and second compressors, as well as with fans of air cooling units.

EFFECT: increase of productivity at reduction of energy consumption.

7 cl, 4 dwg



Same patents:

FIELD: process engineering.

SUBSTANCE: invention relates to cryogenic gas separation of associated oil gases. Process of complex drying and cleaning of associated oil gas comprises gas-dynamic separation and membrane technology of removal of acid compounds. Fed associated oil gas is subjected to two-step drying and cleaning. Main amount of water and heavy hydrocarbon fractions C5 and higher are removed at multistage primary rotary separator at low pressure of 0.3-0.5 MPa. Then, cleaned light hydrocarbon fraction is compressed to 3.0-6.0 MPa and after-purified in extra rotary separator and, then, subjected to cleaning by membrane process from acid compounds H2S and CO2. Cleaned fraction of light hydrocarbons is subjected to vortex power separation in three-flow vortex tube wherefrom produced cold flow is directed for cold recuperation for cooling of initial flow of associated oil gas and discharged as a commercial fraction of C3-C4. Separated fraction of vortex tube cold flow is directed for compression recycling with pre-separated light hydrocarbon fraction. Hot vortex tube flow is discharged as the commercial fuel gas.

EFFECT: optimised separation, drying and cleaning.

1 dwg

FIELD: machine building.

SUBSTANCE: method of partial natural gas liquefaction under option 1 switches on the pre-cooling of direct HP gas flow. After cooling the direct flow is throttled and separated in the rectifier to liquid phase and steam phase. The steam phase is supplied for re-condensation with further supply of part of re-condensed product flow to the rectifier as reflux, and throttling of the other part of the re-condensed product and separation to the liquid phase being finished product, and steam phase sent as back flow for the direct flow cooling. The liquid phase from the rectifier is expanded and due to re-condensation of the steam phase from the rectifier it is evaporated, then it is heated by the direct flow, and after re-throttling is sent to the back flow. In contrast to the option 1 during the partial natural gas liquefaction method under option 2 part of the direct flow after cooling is expanded and mixed with back flow.

EFFECT: suggested group of inventions ensures production of the liquefied natural gas with low content of high boiling components, including carbon dioxide having increased operation characteristics, upon power consumption decreasing for its production.

2 cl, 2 dwg

FIELD: oil and gas industry.

SUBSTANCE: liquefied natural gas production method according to which incoming gas flow is treated from impurities and compressed until it is separated into process and production flows. The process flow is passed through a reducer valve equipped with gas turbine, which torque is used for compression of the incoming gas flow until it is separated into process and production flows. The process flow is treated from impurities of heavy hydrocarbons by their condensation in a nozzle block of the reducer valve, which is made of heat-conductive material. Liquid phase is supercooled before pumping to the consumer's tank.

EFFECT: improved productivity at reduced energy consumption.

7 cl, 1 dwg

FIELD: energy industry.

SUBSTANCE: pre-purified and dried natural gas is cooled and condensed in heat exchanger of pre-cooling, and then it is separated by separating the liquid ethane fraction which is directed to fractionation, and the gas flow from the first separator is successively cooled in heat exchanger of liquefaction using the mixed refrigerant, overcooled with gaseous nitrogen in heat exchanger of overcooling, the pressure of the overcooled LNG is reduced in the liquid expander, and the overcooled LNG is directed to separation, then the liquefied gas is directed to the LNG storage tank, the separated gas is directed into the fuel gas system. The unit for liquefying gas comprises heat exchanger of pre-cooling, five separators, two throttles, the heat exchanger of liquefaction, three compressors designed to compress the mixed refrigerant, five air coolers, two pumps, liquid expander, a heat exchanger of overcooling, a turbo expanding assembly comprising an expander and a compressor, two compressors of nitrogen cycle.

EFFECT: reduction of energy consumption required to carry out the process of gas liquefaction.

2 cl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method is intended for the distribution of low-pressure natural gas to consumers with the production of liquefied gas. The method lies in the extraction of a gas flow from the high-pressure main pipeline, its expansion in a multistage turbine with the production of mechanical energy, heat exchange in a heat exchanger and distribution of the received low-pressure gas to the consumer, at that the gas from the high-pressure main pipeline is directed to an input of a heat carrier loop in a heat exchanger and cooled, while at the loop output it is directed to a multistage turbine where the cooled gas flow is expanded up to a pressure less than the preset distribution pressure in the low-pressure pipeline, at which the fed flow of the liquefied natural gas changes its parameters and aggregative state, transiting from a single-phase state at the multistage turbine input to a double-phase state at the turbine output; at that a liquid phase is separated from the latter and sent for distribution to the liquefied gas pipeline while the remaining part upon separation is sent to the input of the cold carrier loop in the heat exchanger to heat it up for heat exchange with the flow of the liquefied natural gas fed from the high-pressure main pipeline, and further this part is compressed in a bootstrap system up to a pressure equal to the pressure in the low-pressure pipeline, heating it up simultaneously up to positive temperature values, and then it is sent for distribution to the low-pressure pipeline; at that for the compression of this gas part in the compressor mechanical expansion energy is used, which is received at the multistage turbine; moreover, the separation of the liquefied natural gas part takes place after each stage of the turbine.

EFFECT: development of a highly-efficient method of natural gas distribution with simultaneous maximum output of liquefied gas due to mechanical energy produced in result of expansion when pressure drop occurs in the high-pressure main pipeline and low-pressure pipeline.

3 cl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method and system are intended to optimise carbon dioxide cut-off operations and are oriented towards control of operating parameters for a ground-based installation for carbon dioxide compression (CO2) or pipeline for maintenance of CO2 flow in liquid or supercritical state during transportation to the cut-off point. The methods and installation use sensors to determine whether the flow is single-phase or double-phase, and feedback coupling to regulate pressure and/or temperature at the pipeline input.

EFFECT: reduced losses of useful capacity generated by the power plant at separation and compression of CO2 flow passing through the pipeline.

14 c, 16 dwg, 1 tbl

FIELD: machine building.

SUBSTANCE: method of gas liquefaction includes the following stages. The supplied flow is supplied into liquefier, containing, at least, warm expander and cold expander. The supplied flow is compressed in the liquefier up to the pressure above critical one and the compressed supplied flow is cooled down to the temperature below the critical temperature for formation of dense phase high-pressure flow. Dense phase high-pressure flow is taken from liquefier and the pressure of dense phase high-pressure flow is decreased in the expansion device for formation of resulting two-phase flow. Then the resulting two-phase flow is immediately supplied to the storage tank. The selected part of the resulting two-phase flow is merged instantly with boiling out vapour of the liquid in the storage tank for formation of integrated steam flow. And the temperature of dense phase high-pressure flow is lower, than the temperature of output flow of the cold expander. The system of atmospheric gas liquefaction is also described.

EFFECT: development of simple and inexpensive liquefaction method with effective and beneficial extraction of vapours instantly escaped from tanks.

15 cl, 4 dwg, 2 tbl

FIELD: oil-and-gas industry.

SUBSTANCE: invention relates to liquefying of natural or associated oil gas, i.e. propane-butane fraction. Initial flow is cooled, separated to isolate light portion of low-molecular hydrocarbon stock to be liquefied with extraction of liquid propane-butane fraction in power vortex separator. Said vortex separator is composed of three-section vessel accommodating vortex tube to divide the latter into three sections, top, mid and bottom, by horizontal walls. Note here that top section accommodates cold end with vortex tube coil heat exchanger, mid-section accommodating hot end. Bottom section houses hot flow rate regulator and separator of liquid phase from said flow equipped with the valve.

EFFECT: higher yield of pure hydrocarbon stock.

2 dwg

FIELD: oil-and-gas industry.

SUBSTANCE: set of invention relates to liquefaction of high-pressure natural gases and mixes thereof. In compliance with this method, cooled straight gas flow is throttled to divide it into production and process flows. Production flow is cooled, throttled and fed to fractionator to get liquid and vapour fractions. Vapour fraction is fed for recondensation with subsequent fed of a portion of recondensed production flow to fractionator as a reflux irrigation. Another portion of recondensed production flow is throttled and divided into liquid phase, a finished product, and vapour phase to be directed as a return flow for cooling of straight flow. Pre-cooled process flow is throttled, evaporated by production flow recondensation and, after repeated throttling, directed to return flow. Invention covers also a version of natural gas partial liquefaction.

EFFECT: low content of high-boiling components including carbon dioxide, enhanced performances, lower costs.

6 cl, 6 dwg

FIELD: heating.

SUBSTANCE: after associated petroleum gas is cooled in a recuperative heat exchanger, it is separated in a multistage centrifugal separator from oil-petroleum liquid fractions, water condensate and mechanical impurities, which are removed for further processing to a gas fractionation unit, and a gaseous fraction is supplied for two-stage compression. To the first stage together with the separated gaseous fraction there supplied is vapour phase from an above-surface isothermal storage for repeated liquefaction, and gas compressed after the first stage is supplied for liquefaction to a three-flow vortex tube so that cold, hot gaseous and liquid flows are formed. To the second compression stage there supplied is a mixture of a hot flow from the vortex tube and a cold flow after recuperative heat exchangers. Gas flow compressed at the second stage is supplied to the separator after recuperative cooling; after that, the gaseous fraction is supplied to a main gas line or a fuel network, and liquefied gas together with liquid phase separated from hot flow of the vortex tube is supplied to the above-surface isothermal storage.

EFFECT: use of the invention will allow improving efficiency of processes for separation of target hydrocarbon fractions.

1 dwg

FIELD: oil and gas industry.

SUBSTANCE: group of inventions is related to oil production industry, in particular, to secondary and tertiary methods of enhanced oil recovery for beds with low oil saturation that envisage use of equipment for production of gaseous nitrogen with high pressure and temperature. Nitrogen compressor plant comprises a multistage piston-type compressor with a power drive unit made as diesel engine, and gas-separating unit. Output of the compressor intermediate stage is coupled to input of gas-separating unit. Output of gas-separating unit is coupled to input of the compressor stage, which follows the intermediate stage. At that nitrogen compressor plant includes heat exchanger, which working medium input is coupled to the compressor output. Input of the compressor heat exchanger is coupled to exhaust output of diesel engine. Gas-separating unit is made as a hollow-fibre membrane unit. Output of the heat exchanger working medium is coupled to input of additional heater. At that output of the additional heater serves as output of the station.

EFFECT: development of more effective means for oil extraction from low-permeable collectors complicated by high paraffin content.

8 cl, 4 dwg

FIELD: mechanical engineering.

SUBSTANCE: invention relates to compressor equipment, mainly to mobile compressor stations with membrane nitrogen generators, for obtaining of a neutral nitrogen-based gas mix. The station has a screw compressor 1, membrane gas separation unit 3, oil separator 4, air conditioning unit 5 and oil circulation system. The gas separation unit 3 contains the main section 6 and additional sections 7 and 8. The oil circulation system of the compressor 1 includes the oil separator 4, an oil channel of an air heater 18, an oil cooling heat exchanger 24 with a fan 25. The oil cooling heat exchanger 24 and the gas separation unit 3 are located so that the heated air flow downstream the oil cooler flows around the housing details of membrane modules, and towards the movement of the heated air of the section of the gas separation unit are located in a sequence 7-8-6.

EFFECT: heating of switched-off modules is provided and, besides, at the established operating mode of the station the optimum thermal mode of the gas separation unit is ensured.

3 cl, 1 dwg

Compressor plant // 2529431

FIELD: machine building.

SUBSTANCE: resource-saving compressor plant is proposed, it comprises a compressor and a refluxer-stabiliser consisting of refluxing and stabilisation sections fitted by heat and mass exchange unit blocks, lines for the supply of gas being compressed, for compressed gas withdrawal, for cooling agent supply/withdrawal, for the supply of unstable condensate with a throttle valve in it, for the supply of compressate to the stabilisation section, for the supply of cooled compressate to the refluxing section as well as the lines for the withdrawal of stable condensate and supply of stabilisation gas to the line for the supply of gas being compressed. Every next stage in the multistage resource-saving compressor plant is connected to the previous stage by the compressed gas supply line and is fitted by the stable condensate withdrawal line. In case splitting condensate is formed (for example, splitting into hydrocarbon and water phases) the stabilisation section is equipped by the lines to withdraw the condensate phases according to their quantity.

EFFECT: increased output of compressed gas, reduced losses of heavy components with the compressed gas, and production of stable condensate phases with specified pressure of saturated vapour and reduced content of light components.

4 cl, 1 dwg

FIELD: oil and gas industry.

SUBSTANCE: method consists in preliminary cleaning of gas supplied from the inlet header of main gas line, its compression in a process compressor of a gas transfer unit, cooling of transported gas, supply to the outlet header of the main gas line for further transportation. Cooling is performed additionally in a unit of recuperative heat exchangers. A compressor station includes an inlet header of the main gas line, a cleaning unit, a turbo-expander plant, inlet shutoff valves, a gas transfer unit with a process compressor and its drive, outlet shutoff valves, a gas cooler and a unit of recuperative heat exchangers connected in series or parallel, and an outlet header of the main gas line.

EFFECT: reduction of power costs for gas compression and improving the efficiency of gas transfer methods and compressor stations.

4 cl, 2 dwg

FIELD: machine building.

SUBSTANCE: proposed station comprises compressor 1 and gas separation unit 5. Compressor 1 allows adjusting unit efficiency by compressed gas flow rate. Gas separation unit 5 comprises N modules 6 connected in parallel at N≥2. Compressor outlet is communicated with inlet of gas separation unit 5. Outlet of said N gas separation unit modules 5 is communicated with N load units connected in parallel at, N≥2.

EFFECT: simplified design, accelerated selection of operating condition.

12 cl, 1 dwg

FIELD: machine building.

SUBSTANCE: stationary compressor plant located in production area with bearing walls, near one of which there is an additional building with air filter in it connected to suction air pipeline and at the top part of one of the walls there attached is a pressure tank with cooling fluid, connected via pipeline to compressor cooling system that is via oil and fluid separator is connected to air collector located outside of one of the walls of compressor plant building, equipped with acoustic operator cabin. The cabin includes foundation, framework, life-support equipment, window and door openings and enclosures in a form of acoustic panels, foundation is mounted on pneumatic vibration isolators made in a form of rubber-cord casing, and it is rigidly connected to cabin framework made in a form of multi-angle prism with ribs perpendicular to cabin foundation and consisting of front wall with glasing made from noise-reflecting translucent panel, ceiling part with lights, rear wall located in plane parallel to front wall plane, and four side walls, in one of which there is a door. The area of rear wall is larger than the area of front wall. Side walls joined to the front wall are tilted in relation to it and have glasing, and walls joined to rear wall - perpendicular to it. The cabin is air-proof and is equipped with life-support system in a form of artificial microclimate system with control panel, as well as working place that includes working table, a chair with vibration isolators in a form of plates from elastomer attached to chair legs and a hanger for clothes.

EFFECT: increase of plant servicing and operation efficiency due to reduction of noise level in production area of compressor station.

3 cl, 3 dwg

FIELD: engines and pumps.

SUBSTANCE: use of modules of compressor units of larger capacity is implemented at small weight and overall dimensions in comparison to prototype; connection of modules of compressor units is performed to blowdown plugs of cut-out and current sections of main gas line via additional pipelines and shutoff valves, which allows performing preparatory works and connection to cut-out and current sections of main gas line of mobile compressor station without cutting out the main gas line.

EFFECT: shortening of the time required for gas pumping out of cut-out section of main gas line to current section of main gas line in comparison to prototype.

8 cl, 5 dwg

FIELD: engines and pumps.

SUBSTANCE: triple-stage compressor plant comprises compressors of the first, second and third stages, a driving engine and two differential mechanisms. The input shaft of the first differential mechanism is connected to the shaft of the driving engine, and its output shafts are separately connected to the first stage compressor and the input shaft of the second differential mechanism. Output shafts of the second differential mechanism are separately connected to the shafts of compressors of the second and third stages, accordingly.

EFFECT: increased number of compressing stages up to three and increased total range of automatic control of compressor plant efficiency as a whole.

2 dwg

FIELD: engines and pumps.

SUBSTANCE: device is designed for use in compressor building industry in plants that operate with variable injection pressure. A double-stage compressor plant comprises compressors of the first and second stages, a driving engine, two differential mechanisms and two mechanical reducers. The differential mechanisms are assembled into a closed circuit with the help of the mechanical reducers so that the output shafts in such mechanical system are the inlet shaft of one differential mechanism, the outlet shaft of the other differential mechanism and outlet shafts of the mechanical reducers. The shaft of the driving engine is connected to the inlet shaft of one differential mechanism, the outlet shaft of the first stage compressor is connected to the outlet shaft of one of the mechanical reducers, and the outlet shaft of the second stage compressor is connected to the outlet shaft of the second differential mechanism. The output shaft of the other mechanical reducer is connected to the shaft of the braking device. This makes it possible to increase the range of automatic control of the compressor plant efficiency as a whole.

EFFECT: invention makes it possible to set a rational range of automatic control of pressure ratios between compression stages during operation of the compressor plant for a grid with variable pressure.

2 dwg

Compressor unit // 2429148

FIELD: transport.

SUBSTANCE: proposed compressor unit comprises drive and air compressor. Compressor unit incorporates oil coarse filter and/or oil fine filter built in bearing plate and communicated via said plate with one of components. Bearing plate comprises connecting elements for oil stock reservoir and/or coarse oil filter reservoir.

EFFECT: simplified design, hydraulic communication lines in bearing plate.

13 cl, 6 dwg

FIELD: manufacture of compressors; production of nitrogen-based compressed inert gas mixture from atmospheric air.

SUBSTANCE: proposed compressor station mounted on truck chassis includes multi-stage piston-type air compressor, membrane-type gas distributing module and module-type nitrogen plant. Outlet of third compression stage of air compressor is connected via cooler and water-and-oil separator with inlet of gas-distributing module through filter unit. Outlet of gas-distributing module is connected with inlet of air compressor fourth stage. Air compressed preliminarily in compressor stages is cooled down and cleaned in coolers and water-and-oil separators, after which it is delivered through pipe lines to inlet of gas-distributing module and cleaned in filters and water-and-oil separators from condensed moisture, mechanical admixtures and oil and is fed to gas-distributing reservoirs through gas-distributing unit; gas-distributing reservoirs are interconnected and are located in series and/or in parallel; concentration of oxygen in these reservoirs is reduced to 0.1%. Inert nitrogen gas mixture is fed to compressor stages, cooled to temperature below 60°C and cleaned from moisture and oil in coolers and water-and-oil separators of subsequent stages; then, it is fed to consumer through receiver, check valve and cock. During start at negative temperatures, pre-start heater is switched on and high-temperature gases enter preheating chamber and truck body of mobile compressor station. As required temperature has been attained, diesel engine and compressor are started and high-temperature gases are fed from preheating chamber to thermostatted body of module-type nitrogen plant through warm sleeve.

EFFECT: extended field of application; increased service life of station; facilitated procedure of start.

9 cl, 8 dwg