Method for extraction of liquefied hydrocarbon gases from natural gas of main gas pipelines and plant for its implementation
FIELD: oil and gas industry.
SUBSTANCE: flow of natural gas is sequentially cooled and sent to a first low temperature separation stage, then gas separated in the first stage is expanded in a turbo expander and sent to a second low temperature separation stage. Liquid hydrocarbon fraction produced at the first separation stage is also sent after throttling to the second separation stage. The flow of separated gas of methane-ethane fraction is directed by reverse flow for natural gas cooling. The produced liquid flow is fed to the top of deethaniser column, from which gas flow of methane-ethane fraction is taken and after throttling it is combined with reverse gas flow of methane-ethane fraction produced at the second separation stage, then after recuperation of cold, combined flow of methane-ethane gas is additionally cooled and withdrawn from the plant as a commercial gas. After throttling, liquid fraction C3+ produced in the deethaniser column is sent to the middle part of the depropanizer column, from which the gas flow of propane fraction is sent to reflux, after that the produced liquid propane fraction is divided into two flows, the smaller one is fed into the upper part of the depropanizer column as a reflux, and the larger one is withdrawn from the plant. After throttling, liquid flow of C4+ fraction from the bottom of the depropanizer column is sent to the middle part of the debutanizer column, from the top of which the gas flow of butane fraction is sent to reflux. After that, the produced liquid butane fraction is divided into two flows, the smaller one is fed into the upper part of the debutanizer column as reflux, the larger one is cooled and removed from the plant, and after cooling the flow of C5+ liquid fraction is withdrawn from the plant from the bottom of the debutanizer column. The plant comprises two recuperative heat exchangers, two low temperature separators, the deethanizer column, the depropanizer column equipped with reflux condenser including a third recuperative heat exchanger and a separator, the debutanizer column equipped with dephlegmator including water cooler and a separator, three pumps, three air-cooling devices, turbo-expander, four throttles and connecting pipelines.
EFFECT: increased gas processing efficiency, possibility for production propane and butane fractions separately.
2 cl, 1 dwg
FIELD: oil and gas industry.
SUBSTANCE: invention relates to the method of production of liquid CO2 from gaseous combustion products. Furnace gas is compressed in the first compressor, then it is cooled in the first cooler and is partially condensed at two separation steps. Two separation steps are cool by the expanding flue gas and the expanding liquid CO2. The second separation step includes the second heat exchanger and CO2 stripper in which the flow of liquid CO2 from the first separation step is supplied into the CO2 stripper directly and CO2 flow from the first separation step is supplied into the CO2 stripper through the second heat exchanger. Liquid CO2 in the stripper is boiled by the reboiler and from the top part of CO2 stripper flue gas is separated, expanded in the pressure control valve and is used in separation steps for cooling. Also liquid CO2 from the reboiler and CO2 stripper is collected in the buffer drum.
EFFECT: increase of purity of liquefied CO2 without increase of power consumption.
12 cl, 5 dwg, 1 tbl
FIELD: oil and gas industry.
SUBSTANCE: invention group refers to method of carbon dioxide-containing natural gas treatment. Treatment method involves natural gas separation by cryogenic process and can produce liquid carbon dioxide flow at one side and purified natural gas flow at another side. One part of natural gas is cooled in a first heat exchanger and then in a second heat exchanger before the cryogenic process and/or before return to the cryogenic process. One part of liquid carbon dioxide is returned to obtain recycled carbon dioxide flow. Recycled carbon dioxide flow is divided into the first and second portion. First portion is expanded, then heated in the first heat exchanger to obtain first flow of heated carbon dioxide. Second portion is cooled, then at least one part of the second portion is expanded and heated in the second heat exchanger to obtain second flow of heated carbon dioxide. Some hydrocarbons contained in the first and second flows of heated carbon dioxide are separated by gas and liquid separation. Invention claims installation for implementation of the method as well.
EFFECT: reduced hydrocarbon loss during cryogenic separation.
11 cl, 2 tbl, 1 dwg
SUBSTANCE: invention relates to method of removing fraction with high nitrogen content. Described is method of removing fraction with high hydrogen content from initial fraction, which contains mainly nitrogen and hydrocarbons, with initial fraction being separated by method of rectification into fraction with high nitrogen content and fraction with high methane content in order to obtain cold is evaporated and overheated under possibly maximal pressure with respect to initial fraction to be cooled. In accordance with invention still liquid or partially evaporated fraction with high methane content is supplied to circulation tank, liquid portion of fraction with high-methane content formed in circulation tank preferably in the process of natural circulation is completely evaporated, and head main product of circulation tank is overheated.
EFFECT: invention is aimed at reliable and stable evaporation of fraction with high nitrogen content.
7 cl, 4 dwg
SUBSTANCE: invention relates to a method of separating C2+-hydrocarbons from a starting fraction primarily containing nitrogen and hydrocarbons. The disclosed method includes: a) the starting fraction is partially condensed and fractionally divided into C2+-hydrocarbon impoverished and rich fractions; b) the C2+-hydrocarbon impoverished fraction is partially condensed and divided into a liquid fraction which forms at least a partially reverse stream for fractional separation, and a C2+-hydrocarbon impoverished gaseous fraction; c) the C2+-hydrocarbon impoverished gaseous fraction is divided in a double-column process into a nitrogen-rich and a methane-rich fraction. The liquid fraction obtained at step (b) is also at least partially fed into the double-column process and divided therein into a nitrogen-rich and a methane-rich fraction.
EFFECT: invention is aimed at improving the efficiency of separating C2+-hydrocarbons.
4 cl, 3 dwg
SUBSTANCE: method and device of liquefaction of a gaseous flow, which contains hydrocarbons and acidic compounds, and in which the acidic compounds are removed in a liquefied state, when the gaseous flow, purified from the acidic compounds is gradually cooled to the liquefaction temperature. The method includes cooling the gaseous flow in such a way as to obtain the cooled gaseous flow, containing gaseous hydrocarbons and residual acidic compounds. After that, the obtained gaseous flow, purified from the acidic compounds, is additionally cooled to obtain liquid hydrocarbons.
EFFECT: method improvement.
20 cl, 2 dwg
SUBSTANCE: method of separating inert gases from gases containing argon, xenon, krypton, nitrogen and hydrogen includes cooling a starting gas stream, cooling and separating via two-step fractionation to obtain liquid separation products: argon, krypton-xenon mixture, and gaseous separation products: nitrogen and a nitrogen-hydrogen mixture. The first fractionation step includes preliminary separation to obtain a reflux. The reflux obtained at the first fractionation step is used for refluxing at the second fractionation step. Before fractionation at the second step, a large portion of the gas stream after cooling undergoes preliminary separation into a gaseous fraction, which is condensed and separated, and a liquid fraction - a reflux, which is returned to the first fractionation step and then fed for supercooling before use for refluxing at the second fractionation step. The smaller portion of the gas stream is compressed before cooling. The smaller portion of the gas stream is cooled in three steps and said portion is filtered between the second and third cooling steps.
EFFECT: reduced harmful emissions and enabling extraction of inert gases from tail gases with maximum output of argon.
10 cl, 1 dwg
SUBSTANCE: invention relates to a method of removing a fraction with high nitrogen content from a starting fraction primarily containing nitrogen and hydrocarbons. The starting fraction is partially condensed and divided by fractionation into a fraction with high nitrogen content and a fraction with high methane content. According to the invention, during cut-off of the supply of the starting fraction being fed for fractionation, the separation column(s) (T1/T2) and heat exchangers (E2) serving for partial condensation (E1) of the starting fraction and cooling and heating process streams formed during fractionation are kept, through one or more different coolants (6-11), at temperature levels substantially corresponding to temperature levels during the normal operating mode of the separation column(s) T1/T2) and heat exchangers (E1, E2).
EFFECT: improved method.
2 cl, 4 dwg
SUBSTANCE: method of producing a multicomponent solution of a krypton-xenon mixture and a special purity solvent involves feeding a multicomponent solution into a precursor solution line, preliminary physical-chemical purification from explosive and hardening impurities, cooling and fractional separation in columns. Said columns are equipped with samplers in the concentration part or blow line and the vapour zone of the bottom. A krypton-xenon mixture containing volatile impurities and a stream of a solvent containing volatile impurities are obtained in the column for obtaining a krypton-xenon mixture. The method also includes purifying the stream of the solvent fraction in a column for obtaining special purity solvent from volatile impurities to obtain a special purity solvent. All impurities that are volatile relative to krypton are removed with the stream of the solvent fraction, wherein the part of said impurities which is semi-volatile relative to the solvent is removed in a column for purification from intermediate impurities. An apparatus for carrying out said method is described.
EFFECT: invention reduces content of impurities in a krypton-xenon mixture, simplifies and reduces the cost of processing said mixture.
3 cl, 1 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to method of removal of fractions with high content of nitrogen from initial fraction containing, mainly, nitrogen and hydrocarbons. Note here that initial fraction is separated by rectification into high nitrogen fraction and high methane fraction. High-methane fraction is evaporated and overheated at maximum possible pressure to produce cold. High-nitrogen fraction is at least temporarily and/or partially contracted and fed to rectification as a backflow. In compliance with this invention, at least temporarily, at least partially one partial flow (16) of compressed (C) fraction (9') with high nitrogen content after performed condensation (E1) is expanded (f) in valve and, to produce cold, at least partially, preferably completely, is evaporated (E1).
EFFECT: uniform distribution of compressor load irrespective of nitrogen concentration in initial fraction.
7 cl, 2 dwg
FIELD: machine building.
SUBSTANCE: invention relates to a cyclone separator for fluid medium, comprising a neck part (4), which is placed between the section of inlet of the convergent fluid medium and the section of outlet of the divergent fluid medium. The cyclone separator for fluid medium is made with the capability to push the cyclone flow via the section of inlet of the convergent fluid medium and the neck part to the section of outlet of the divergent fluid medium in direction downstream the flow. The section of outlet of the divergent fluid medium comprises an inner primary outlet pipe (7) for fluid components depleted by condensing vapours and an outer secondary outlet pipe (6) for fluid components enriched with condensing vapours. The cyclone separator for fluid medium comprises an additional outer secondary outlet pipe (16). The outer secondary outlet pipe (6) is placed in the first position along the central axis (I) of the cyclone separator for fluid medium, and the additional outer secondary outlet pipe (16) is placed in the second position along the central axis (I) of the cyclone separator for fluid medium.
EFFECT: higher efficiency of a separator and purity of produced fractions.
FIELD: processing petroleum gases by low-temperature condensation; oil and gas processing industry.
SUBSTANCE: proposed method includes compression of initial gas followed by de-ethanization. Gas and condensate obtained after separation are mixed and gas-and-liquid flow is cooled and is delivered for low-temperature separation; then, part of this low-temperature condensate is throttled and cold thus obtained is used for cooling the compressed gas-and-liquid flow which is fed for separation of condensate, after which gas separated from condensate is mixed with initial gas and condensate is directed for de-ethanization. Second part of low-temperature condensate is fed for de-ethanization after use of its cold for cooling and condensing the de-ethanization gases.
EFFECT: possibility of extraction of target components; utilization of heavy petroleum gases; reduced capital outlays.
4 cl, 1 dwg
FIELD: cleaning and separation of mixtures of isotopes and isotope compounds at low separation coefficient.
SUBSTANCE: proposed method includes separation of mixture by rectification in column divided into sections and taking the liquid from under contact space of previous section which is delivered by activator for sprinkling the subsequent section above contact space followed by taking vapor above contact space of subsequent section and delivery of it under contact space of previous section. Used as activator is steam lift communicated with contact spaces of sections through hydraulic seals; evaporation of liquid and condensation of steam in steam lift are performed by delivery of working medium circulating in high-pressure and low-pressure cycles. Description of device proposed for realization of this method is given in Specification.
EFFECT: reduced usage of metal; reduced power requirements.
5 cl, 1 dwg
FIELD: cryogenic technique, particularly for separating the constituents of gaseous mixtures involving the use of liquefaction or solidification.
SUBSTANCE: method involves compressing neon-helium mixture flow, cooling thereof and separating under 28-29.5 K temperature and pressure exceeding critical neon pressure to form stripping gas and liquid fraction; additionally absorbing neon from stripping gas by adsorbers; purging adsorbers with helium during desorption thereof; mixing purging gas with neon-helium mixture before compressing thereof. Separation device comprises compressor with inlet pipeline, main heat-exchanger with stripping gas inlet and outlet connection pipes, low-temperature heat-exchanger, separator with stripping gas and liquid fraction outlet pipelines, rectifying column with evaporator in column bottom and alternating adsorbers. Gas inlet connection pipe of each adsorber is connected to stripping gas outlet pipeline of separator downstream of low-temperature heat-exchanger and to compressor inlet pipeline through pipelines provided with valves. Gas outlet connection pipe of each adsorber is linked with stripping gas inlet and outlet connection pipes of main heat-exchanger through pipelines provided with valves. Evaporator has capillary-porous coating applied from boiling side thereof.
EFFECT: increased economic efficiency and reduced metal consumption.
2 cl, 1 dwg
FIELD: processes or apparatus for separation.
SUBSTANCE: method comprises supplying vapors of cooling agent to the cooling cycle for liquefying, mixing the liquid cooling agent with the liquefied cooling agent, and supplying the liquid cooling agent to the condenser-evaporators for evaporating.
EFFECT: reduced consumption of cooling agent.
FIELD: gas industry, particularly to cool pressurized liquefied natural gas containing methane and hydrocarbons with two or more carbon atoms.
SUBSTANCE: method involves expanding above pressurized liquefied natural gas to obtain expanded liquefied gas flow; separating the obtained gas flow into the first head fraction having greater volatility and the first tail fraction having lesser volatility; accumulating the first tail fraction comprising cooled liquefied natural gas; heating the first head fraction, compressing thereof in the first compressor and cooling the first head fraction to obtain the first compressed fraction of combustible gas; accumulating the first fraction of combustible gas; extracting the second compressed fraction from the first compressed one; cooling the second compressed fraction and mixing thereof with expanded liquefied natural gas flow; compressing the second compressed fraction in the second compressor communicated with turboexpander to obtain the third compressed fraction; cooling the third compressed fraction and separating thereof into the forth and the fifth compressed fractions; cooling the forth compressed fraction and expanding thereof in turboexpander connected to the second compressor to obtain expanded fraction; heating the expanded fraction and introducing thereof into the first medium-pressure compressor stage; cooling the fifth fraction and mixing thereof with expanded liquefied natural gas flow.
EFFECT: increased output.
13 cl, 11 tbl
FIELD: gas conditioning, separation and liquefaction, particularly for natural gas in oil industry.
SUBSTANCE: method involves treating gas; separating thereof in membrane or cryogenic gas-separation unit; liquefying and separating gas in liquefying unit. Gas treatment includes cleaning gas of water droplets and mechanical injuries and supplying the cleaned gas to gas-separation unit inlet. Then natural gas is cleaned and supplied through gas distribution means to gas-separation vessels which increase methane concentration to 99.9%. Methane moves to gas liquefying unit inlet. Nitrogen and hydrocarbons are separated in serially connected gas-separation vessels into ethane, propane, butane and nitrogen. Ethane, propane and butane are directed to store means. Cryogenic unit is adapted for cleaned natural gas dividing into two flows, which are cooled, combined and then expanded. The expanded flow is supplied to rectification column. Flow of the first steam is cooled to -112°C - -150°C temperature to form vapor and liquid phases by passing the first steam through a row of heat exchangers in which the first steam is in counterflow with nitrogen flow circulating in cooling loop. The cooled flow of the first steam is separated into vapor and liquid phases to create flow of the second steam having methane and nitrogen ratio of 1:(1.0-2.0) and to create flow of the second liquid having methane and nitrogen ratio of 1:(4.0-2.0). Flow of the second liquid in phlegm form is returned to rectification column and the first liquid is removed from rectification column, wherein the first liquid is product having temperature exceeding -112°C. The product is directed to high-pressure natural gas store means and to liquefying unit, in which gas is separated inside de-methanizing, de-ethanizing, de-butanizing and de-propanizing columns. Then pressure and temperature of the gas flows exited from the columns are equalized and the flows are combined into single flow. Part of the flow is reduced and supplied to operator's compartment.
EFFECT: extended field of method and device application, increased device reliability and quality of obtained gases.
9 cl, 4 dwg, 1 tbl
FIELD: separation of gases or gaseous mixtures.
SUBSTANCE: method comprises cooling mixture, expanding mixture or its portion, partial condensing of the mixture with its simultaneous expansion, and separating the mixture or its portion in the rectifying tower to produce liquid and gas phases. The expansion is performed by flowing the mixture through the nozzle passage. The nozzle passage swirls the flow of the mixture. The mixture flow is separated at the outlet of the nozzle passage at least into two flows. One of the flow is enriched by the components denser than methane, and the other one is depleted by these component. The enriched flow is directed to the rectifying tower. The gas products produced in the rectifying tower are directed to the mixture upstream of its expansion. According to the second version, the gas products are mixed completely or in part with the depleted flow. According to the third version, the enriched flow is directed completely or in part to the mixture upstream of its expansion. According to the fourth version, the enriched flow and gas products are directed in part or completely to the mixture upstream of its expansion.
EFFECT: enhanced efficiency.
64 cl, 22 dwg
FIELD: chemical industry.
SUBSTANCE: method comprises treating gas in one or several heat exchange stages to produce first raw flow cooled under pressure, expanding the first raw flow to decrease the pressure, supplying raw to the fractionating column, and fractioning cooled and expanded first raw flow at a lower pressure thus extracting relatively light components. The distillation flow is discharged from the fractioning column and heated. The heated distillation flow is returned to the fractioning column.
EFFECT: enhanced quality of fractioning.
24 cl, 9 dwg, 2 tbl
FIELD: gas processing industry; methods of separation of the components of the gaseous mixtures.
SUBSTANCE: the invention is pertaining to the field of the gases processing industry, in particular, to the methods of separation of the components of the gaseous mixtures by the low-temperature condensation and rectification for the purpose of production of the helium concentrate, ethane and the wide fraction of the light hydrocarbons, and may be used at the enterprises of the gas-processing industry. The method provides for: the preliminary cooling of the hydrocarbon gas and its partial condensation; separation of the first stage with separation of the liquid phase from the gaseous phase; the subsequent additional cooling and condensation of the gaseous phase; the separation of the second stage for the liquid and the vapor phases; condensation and rectification of the vapor phase in the flash tower, separation of the third stage of the part of the bottoms product of the flash tower for the liquid phase and the vapor phase; demethanization and deethanization of the whole separated liquid phase. At that the hydrocarbon gas is preliminary dressed with the pentane- hexane fraction, and the separation of the third stage is realized in the separator additionally equipped with mass-exchange nozzle, onto which the liquid phase flow is fed from the separator of the first stage. The technical result of the invention consists in provision of the additional extraction of ethane.
EFFECT: the invention ensures additional extraction of ethane.
1 dwg, 2 tbl, 1 ex
FIELD: cryogenic engineering; methods of control of the rectification plants operation.
SUBSTANCE: the invention is pertaining to the field of the cryogenic engineering, in particular, to the control of the rectifying plants operation on rectification and separation of the krypton-xenon concentrate produced by the air-fractionating apparatus. The method of control of the rectification plant operation for reprocessing the compressed mixtures includes the control over consumptions of the source mixture in the plant and feeding of the rectifying columns, the pressures and amounts of the top and bottom products gated out of the columns. The rectifying columns are equipped with the sampling devices arranged in their concentration section and the condensers-evaporators with the intermediate coolant in the closed cavity. The mixture at the inlet of the plant is stabilized by the temperature and pressure. Consumption of the mixture by the plant is controlled by the throttle valve, ensuring the pressure drop on the throttle valve for the critical efflux of the mixture. In addition conduct the analysis from the still bottom evaporation area. At that for each column they determine the key components and their share in the preliminary analysis and the analysis from the still bottom evaporation area. The concentrations of the key components are regulated by variation in the contact device of the vapor and the condensate streams. The separation of the top product is conducted in the gaseous form with the constant consumption, the still bottom product is taken out permanently or periodically in the vapor and (or) fluidic form depending on the results of the share of the key component in the mixture from the still evaporation area with the subsequent gasification before the control valve. The useful volume of the still is magnified concerning the hourly productivity of the appropriate column for the bottom product no less than two times, and the pressure in the contact device of the columns is set by variation of the pressure and (or) amount of the intermediate coolant and the heat power of the still boiler of a beck. Usage of the invention ensures the power saving control over the rectifying plant at production of the especially pure target components.
EFFECT: invention ensures the power saving control over the rectifying plant at production of the especially pure target components.