EA022763B1 - Hydrocarbon gas processing - Google Patents

Abstract

The present invention provides improved recovery of Ccomponents, Ccomponents, and heavier hydrocarbon components or of Ccomponents and heavier hydrocarbon components per amount of utility consumption required to operate the process. An improvement in utility consumption required for operating the process may appear in the form of reduced power requirements for compression or re-compression, reduced power requirements for external refrigeration, reduced energy requirements for supplemental heating, or a combination thereof.

Description

This invention relates to a method and apparatus for separating a gas containing hydrocarbons. According to ch. 35 section 119 (e) of the US law applicants claim the priority of provisional application US 61/186361, filed on June 11, 2009. Applicants also claim priority to a partially continuing US patent application 12/689616, filed January 19, 2010, according to Sec. 35 section 120 US law. Successors δ.Μ.Ε. Prosperity 18 LR and Θήΐοίί Eidszhegeg, IB were parties to a research agreement that was valid until the invention was created in accordance with this application.

Hydrocarbons such as ethylene, ethane, propylene, propane, as well as heavier ones, can be extracted from various gases, for example, from natural, refinery and synthesized gas obtained by processing other hydrocarbon materials, such as coal, crude oil, gasoline-benzene fraction, combustible shale, oil sands and lignite. Natural gas consists mainly of methane and ethane, i.e. the molar percentage of methane and ethane in the gas reaches 50%. The gas also contains relatively small amounts of heavier hydrocarbons, such as propane, butane, pentane, and the like, as well as hydrogen, nitrogen, carbon monoxide, and other gases.

In the present invention, a method for extracting ethylene, ethane, propylene, propane and heavier hydrocarbons from such gas streams is mainly considered. The gas suitable for processing in accordance with the present invention has the following typical composition, expressed in molar percent: 90.3% methane; 4.0% ethane and other C ₂ components; 1.7% propane and other C ₃ components; 0.3% isobutane; 0.5% standard butane and 0.8% pentanes and heavier hydrocarbons, balance maintained by nitrogen and carbon dioxide. The presence of sulfur-containing gases is also sometimes noted.

Historically established cyclical changes in prices for both natural gas and its gas condensate (LI) components at times determine a decrease in the growth of ethane, ethylene, propane, propylene, and heavier components as liquid products. As a result, a need has emerged for technological methods that could provide more efficient extraction of these products from the raw gas, while the extraction efficiency should be accompanied by a decrease in investment. The already known methods of separation of these materials include methods based on the cooling and liquefaction of gas, the absorption of oil and the absorption of cooled oil. In addition, cryogenic methods have gained popularity due to the availability of cost-effective equipment that generates electricity by directing gas into the expander and simultaneously removes heat from the process gas. Depending on the pressure of the gas supply source, the gas saturation (ethane, ethylene and heavier hydrocarbon components), as well as the desired final product, any of these methods or their combination can be used.

Today, for the processing of natural gas condensate, preference is mainly given to the method of cryogenic expansion, as it combines maximum simplicity, ease of commissioning, operational flexibility, high efficiency, safety and high reliability. U.S. Patents 3,293,280; 4061481; 4,140,504; 4157904; 4,171,964; 4185978; 4251249; 4278457; 4519824; 4617039; 4,687,499; 4689063; 4,690,702; 4,854,955; 4869740; 4889545; 5275005; 5555748; 5566554; 5568737; 5771712; 5,799,507; 5881569; 5890378; 5983664; 6182469; 6578379; 6,712,880; 6915662; 7191617; 7219513; in the replacement US patent No. 33408; as well as concurrently pending applications with numbers 11/430412; 11/839693; 11/971491 and 12/206230; A description is given of the corresponding methods (although in the description of the present invention, processing modes other than those described in the above US patents are used in some cases).

In a typical cryogenic expansion process, the pressurized gas is cooled by heat exchange with other process streams and / or with external sources of cooling, such as the propane compression cooling system. As the gas cools in one or more separators, condensation and condensate collection occur, as high-pressure condensate contains a certain amount of the necessary C ₂ + components. Depending on the saturation of the gas and the amount of condensate obtained, condensate under high pressure may be subjected to expansion at lower pressure and separation into fractions. The result of evaporation, which occurs during condensate expansion, is to further cool the workflow. Under certain conditions, it may be necessary to pre-cool the condensate under high pressure before its expansion in order to further reduce the temperature as a result of expansion. The expanded work stream, consisting of a mixture of condensate and vapor, is divided into fractions in a distillation column (demethanizer or de-ethanizer). Inside the column, the cooled stream undergoes rectification in order to separate residual methane, nitrogen and other volatile gases in the form of helmet vapors, from the required C ₂ components, C ₃ components and heavier hydrocarbon components, which are discharged from the bottom of the column as a liquid bottom product; or for the purpose of separating residual methane, C ₂ components, nitrogen and other volatile gases in the form of helmet fumes, from the necessary C ₃ components and heavier hydrocarbon components, which are discharged from the bottom of the column as a liquid bottom product.

In the case of incomplete condensation of the feed gas (usually this happens), the vapors remaining after the non-full condensation can be divided into two streams. One part of the vapor is directed through the expander or expansion valve into a container with a lower pressure, where as a result of further cooling of the working stream, additional liquid condensation occurs. The pressure after expansion is actually equal to the pressure under which the distillation column operates. The vapor and liquid phases resulting from the expansion are fed to the column as feedstock.

The remaining vapors are cooled to complete condensation by heat exchange with other process streams, for example, with the top product of the cold distillation column. Before cooling, these vapors can be mixed with part of the condensate under high pressure or with its entire volume. The resulting cooled stream is then expanded in a suitable device, for example in an expansion valve, of the working pressure of the demethanizer. In the expansion process, some of the condensate evaporates, causing the main workflow to cool. The vaporized flow is then fed to the top of the demethanizer. Usually, the vaporous component of the stream throttled by evaporation and the helmet vapors from the demethanizer are mixed in the upper separator section of the distillation column and form residual synthetic methane gas. Alternatively, it is possible to supply the cooled expanded working stream to a separator for its separation into vapor and liquid streams. The vaporous stream is mixed with the helmet vapors of the column, and the condensate is fed into the upper part of the column as a liquid raw material.

Under ideal conditions, with this separation method, the residual gas leaving the plant will contain almost all of the methane that was in the feed gas, while the heavier hydrocarbons and the bottom fraction of the distillation leaving the demethanizer will not contain methane or more volatile components. In practice, however, ideal conditions cannot be created, since the conventional demethanizer mainly works as a stripping column. The methane product obtained according to the method, therefore, usually consists of vapors of the upper zone of the distillation column, as well as vapors that have not undergone rectification. There are significant losses of components C ₂ , C ₃ and C ₄ +, since the liquid raw material that is fed into the upper part of the column contains a sufficient amount of these and heavier hydrocarbon components, resulting in a number of components C ₂ , components C ₃ , components C ₄ and heavier hydrocarbon components are almost equal to their number in the pair, which is released in the upper zone of the demethanizer rectification. Data loss of the necessary components can be significantly reduced if the vapors rising from the rectification zone come in contact with a sufficient amount of condensate (from the reflux stream) capable of absorbing the C ₂ , C ₃ , C ₄ components and heavier hydrocarbon components from the steam.

In recent years, preferred are methods for the separation of hydrocarbons, where an additional absorption section is provided for additional vapor rectification in the installation. The source of the return stream for the upper distillation section is usually the recycled stream of residual gas supplied under pressure. Recycled residual gas stream is usually cooled to significant condensation due to heat exchange with other process streams, such as a cold head distillation column. The resulting cooled stream is then expanded in a suitable device, for example in an expansion valve, to the operating pressure of the demethanizer. In the expansion process, part of the condensate is usually evaporated, with the result that the main workflow is cooled. The vaporized flow is then fed to the top of the demethanizer. Usually, the vapor component of the stream throttled by evaporation and the helmet pairs from the demethanizer are mixed in the upper separator section of the distillation column and form residual methane gas. Alternatively, it is possible to supply the cooled expanded working stream to the separator, where it is divided into steam and condensate streams, after which the steam is mixed with the head stream of the column, and condensate is fed to its upper part as a raw material. Typical schemes of this method are described in US patents numbered 4889545; 5568737; 5881569, as well as in concurrently pending applications with the numbers 11/430412 and 11/971491; as well as in the report of Mowri, E. Ross. Efficient extraction of liquids from natural gas using a high-pressure absorber, which was presented at the 81st annual conference of the Association of Gas Processors in Dallas, Texas, March 11-13, 2002

The present invention uses the latest means of implementing the various steps of the above method, which allows to increase the overall efficiency and reduce the number of necessary equipment. This is achieved by combining in a single installation several pieces of equipment that were previously independent, while reducing the area required for the installation of the technological installation, as well as reduced capital costs. Unexpectedly, the applicants found that a more compact scheme also contributes to a significant reduction in power consumption required to achieve a given level of processing, which generally improves process efficiency and reduces the cost of operating the installation. In addition, a more compact layout allows us to exclude a significant part of the pipelines, with the help of which individual units of equipment were connected in installations of traditional design, which further reduces capital costs and allows removing the corresponding flange connections for connecting pipelines from the structure. Since the flange pipe connections potentially

- 2 022763 possible leakage of hydrocarbons (which are volatile organic compounds (VOS) involved in the formation of gases that cause the greenhouse effect, as well as creating prerequisites for the formation of holes in the ozone layer), the failure of these flanges in the design reduces the possibility of emissions of pollutants in the atmosphere.

In accordance with the present invention, it was found that it is possible to achieve a level of excretion of C ₂ more than 95%. Similarly, in those cases where the selection of the C ₂ components is undesirable, the selection of the C ₃ components is possible at a level exceeding 95%. In addition, the present invention allows for 100% separation of methane (or C ₂ components) and components lighter than C2 components (or C3 components), as well as heavier components, at a lower energy intensity compared with the prior art, with This selection level remains unchanged. The present invention (although it is implemented at lower pressures and higher temperatures) is especially effective when processing raw gases in the pressure range from 400 to 1500 psig. inch abs. (2,758-10,342 kPa (a)) or higher, under conditions where the temperature of the top product of the condensate separation column is in the range of -50 ° P (-46 ° C) or lower.

To facilitate understanding of the essence of the present invention, the following drawings and examples are provided in the description.

FIG. 1 is a block diagram of a natural gas processing facility configured in accordance with the prior art, according to US Pat. No. 5,568,737;

FIG. 2 is a block diagram of a natural gas processing facility constructed in accordance with the present invention;

FIG. 3-9 are flowcharts illustrating alternative uses of the present invention for treating a natural gas stream.

In the following description of the above drawings, tables are presented with summary data on gas consumption calculated for typical processing conditions. In the tables in this document, the gas flow rate (mol per hour) is rounded to the nearest whole number for ease of reading. The total flow rates shown in the tables take into account all non-hydrocarbon components and, therefore, are larger than the sum of the hydrocarbon components. The temperatures shown in the tables are approximate, rounded to degrees. It should also be noted that the calculations of technological schemes in order to compare the effectiveness of the technical methods displayed on the drawings are based on the assumption that there is no heat leakage between the environment and the method (in both directions). The quality of insulating materials on the market makes it possible to consider such an assumption justified, despite the fact that specialists with an appropriate level of technical training usually use it in their calculations.

For convenience of perception, technological parameters are indicated both in traditional British units of measurement and in units of measurement of the International System of Units (SI). The molar gas flow rate indicated in the tables can be expressed either as pound-mole per hour or kilogram-mole per hour. The energy consumed, expressed in horsepower (hp) and / or in thousands of British thermal units per hour (MBTE / h), corresponds to the specified molar flow, expressed in pound moles per hour. The energy consumed, expressed in kilowatts (kW), corresponds to the indicated molar flux, expressed in kilogram-moles per hour.

Description of the prior art

FIG. 1 shows a flowchart of a process method, which shows the design of a processing device designed to separate C ₂ + components from natural gas, implemented on the basis of known technical solutions, in accordance with US Pat. No. 5,568,737. According to this method modeling scheme, the incoming gas enters at a temperature of 110 ° P (43 ° C) and a pressure of 915 psi. inch abs. (6.307 kPa (a)) as stream 31. If the incoming gas contains sulfur compounds in a concentration that violates the requirements for the composition of the working stream, they are removed from the incoming gas using an appropriate pretreatment unit (not shown). In addition, the feed stream is usually dehydrated to prevent the formation of hydrate (ice) during cryogenic treatment. For these purposes, a solid adsorbent is usually used.

The feed stream 31 is divided into two streams 32 and 33. The stream 32 is cooled to a temperature of -26 ° P (-32 ° C) in the heat exchanger 10 due to heat exchange with the cold stream of distant vapor 41a; the stream 33 is cooled to a temperature of -32 ° P (-35 ° C) in the heat exchanger 11 due to thermal exchange with the liquid reboiler condensate of the demethanizer having a temperature of 41 ° P (5 ° C) (stream 43) and with the secondary liquid reboiler condensate having temperature -49 ° Р (-45 ° С) (stream 42). Flows 32a and 33a recombine and form flow 31a, which enters separator 12 at -28 ° P (-33 ° C) and pressure of 893 psi. inch abs. (6155 kPa (a)), where steam (stream 34) is separated from liquid condensate (stream 35).

Steam (stream 34) from separator 12 is divided into two streams - stream 36 and 39. Stream 36, containing about 27% of the total vapor volume, is mixed with the concentrate in the separator (stream 35), and the resulting stream 38 is passed through a heat exchanger 13, where the selection heat is produced due to the interaction with the flow of cold distant vapor 41, where the working flow is cooled to its complete confinement. The resulting condensed stream 38a at -139 ° P (-95 ° C) is then subjected to rapid evaporation through expansion valve 14 to the working pressure (approximately 396 psi abs. (2.730 kPa (a))) of the distillation column 18. In In the expansion process, part of the flow evaporates, causing the main workflow to cool. In the process method, which is illustrated in FIG. 1, the expanded stream 38b after the expansion valve 14 reaches a temperature of -140 ° P (-95 ° C) and is fed to the distillation column 18 at the first middle feed point of the column.

The remaining 73% of the volume of steam from the separator 12 (stream 39) is fed to the working expander 15, where the energy of this part of the raw material under high pressure is converted into mechanical. In the expander 15, the steam undergoes isentropic expansion to the operating pressure of the column, while the expanded stream 39a is cooled to a temperature of approximately -95 ° P (-71 ° C). Typical expanders presented on the market, allow to allocate about 80-85% of technological raw materials, theoretically available with perfect isentropic expansion. The released energy is often used to drive a centrifugal compressor (such as element 16), which, for example, can be used to recompress a heated residual gas (stream 41b). The partially condensed expanded stream 39a is then fed as feed to the distillation column 18 at its second midpoint.

The recompressed and cooled stream of distant steam 41e is divided into two streams. One part, stream 46, is a volatile residual gas. The second part, the recycled stream 45, is fed to the heat exchanger 10, where it is cooled to a temperature of -26 ° P (-32 ° C) due to heat extraction by the cold stream of the distant vapor 41a. The cooled recycled stream 45a is then fed to the heat exchanger 13, where it is cooled to -139 ° P (-95 ° C) and almost completely condenses due to heat recovery by the cold stream of distant vapor 41. The condensed stream 45b is then expanded using a suitable device, for example the expansion valve 22, its pressure is reduced to the working pressure of the demethanizer, with the result that the main working flow is cooled to -147 ° P (-99 ° C). The expanded stream 45c is then fed to the upper part of the distillation column 18 as raw material. The vaporous portion of stream 45c (if present) is mixed with vapors rising from the upper part of the distillation zone of the column and forms a stream of stripping steam 41, which is discharged from the upper zone of the column.

The demethanizer in column 18 is a conventional distillation column in which several trays are installed with intervals between them, one or more nozzles, or a combination of trays and nozzles. As is often the case with natural gas processing devices, a distillation column can consist of two sections. The upper section 18a is a separator, where the feed supplied from the top, containing steam, is divided into steam and liquid, respectively, and where the steam coming from the bottom section of the rectification or demethanization 18b is mixed with the steam separated from the feed from the top of the raw material, resulting in cold helmet steam of demethanizer (stream 41), which is discharged from the top of the column at a temperature of -144 ° P (-98 ° C). The bottom section, the demethanization section 18b, contains trays and / or nozzles and provides the necessary contact between the condensate flowing downwards and the vapors rising upwards. In the demethanization section 18b, reboilers (such as the reboiler and side reboiler, described earlier) are also installed, where the condensate flowing into the bottom of the column is heated and evaporated to form stripped steam that rises up the column to distill off the liquid product, stream 44, methane and lighter components.

The liquid product flow 44 leaves the bottom of the column at 64 ° P (18 ° C) based on typical requirements for a methane: ethane ratio of 0.010: 1, based on the weight of the bottom product. The flow of helmet steam 41 from the demethanizer moves towards the incoming feed gas and recirculated flow in the heat exchanger 13, where it is heated to -40 ° P (-40 ° C) (stream 41a), and also in the heat exchanger 10, where it is heated to 104 ° P (40 ° C) (stream 41b). Then the stream of distant vapor is subjected to secondary compression in two stages. The first stage is the compressor 16, which is driven by the expander 15. The second stage is the compressor 20, which is driven by an additional energy source; here the residual gas (stream 41ά) is compressed to pressure in the distribution pipeline. After cooling to 110 ° P (43 ° C) in exhaust cooler 2, stream 41e is divided into residual gas (stream 46) and recycled stream 45, as previously described. The residual gas flow 46 enters the pipeline under pressure of 915 psi. inch abs. (6307 kPa (a)), which is sufficient to meet the requirements for pressure in the pipeline (usually the input pressure).

Summary data on consumption and power consumption for the method shown in FIG. 1 are given in the following table. I.

- 4 022763

Table I (Fig. 1). Consumption data - lb mol / h (kg mol / h) Flow Methane Ethane Propane Bhutan + Total 31 12398 546 233 229 13726 32 8431 371 159 156 9334 33 3967 175 74 73 4392 34 12195 501 179 77 13261 35 203 45 54 152 465 36 3317 136 49 21 3607 38 3520 181 103 173 4072 39 8878 365 130 56 9654 41 13765 thirty 0 0 13992 45 1377 3 0 0 1400 46 12388 27 0 0 12592 44 ten 519 233 229 1134 Dedicated components *

Ethane 94.99%

Propane 99.99%

Bhutan + 100.00%

Power

Compression of residual gas 6.149 hp [10,109 kW!

* based on non-rounded flow rates

Detailed Description of the Invention

FIG. 2 is a block diagram of a process in accordance with the present invention. The composition and characteristics of the feed gas taken into account in the method shown in FIG. 2 are similar to those of FIG. 1. Accordingly, the method shown in FIG. 2 can be compared with the method of FIG. 1 in order to demonstrate the advantages of the present invention.

When simulating the method according to the scheme shown in FIG. 2, the incoming gas enters the installation in the form of a stream 31, which is divided by the first separation device into two more streams: stream 32 and stream 33. The first stream, stream 32, enters the heat exchange device in the upper part of the cooling section of the raw material 118a, which is located inside the processing 118. A heat exchanger made of finned tubes, a plate heat exchanger, a brazed aluminum heat exchanger or a different type of heat exchanging device, including multi-pass and / or multi-function, can be used as a heat exchanger. ionalnye heat exchangers.

The heat exchange device is designed to provide heat exchange between the flow 32 flowing through one heat exchanger and the flow of distant steam rising from the section of the separator 118b located inside the processing unit 118, which is heated in the heat exchanger of the bottom section of the raw material cooling section 118a. Stream 32 is cooled, while heating of the distant vapor flow continues, and stream 32a leaves the heat exchange device, having a temperature of -25 ° P (-32 ° C).

The second part of the stream, stream 33, enters the heat and mass transfer device in the demethanization section 118e, which is located inside the processing unit 118. A heat exchanger made of finned tubes, a plate heat exchanger, a brazed aluminum heat exchanger or a heat exchanger of a different type, including multiport, can be used as the heat and mass transfer device. and / or multifunctional heat exchangers. The heat and mass transfer device is designed to provide heat exchange between the stream 33 flowing in one run of the heat and mass transfer device and the flow of distant condensate downward from the adsorption section 1186, which is located inside the processing unit 118; Thus, the stream 33 is cooled by heating the stream of distant condensate. At the outlet from the heat and mass transfer device, the temperature of the cooled stream 33a is -47 ° P (-44 ° C). As the flow of the distant condensate is heated, part of it evaporates and forms stripped vapors, which rise up while the remaining liquid condensate continues to flow down through the heat and mass transfer device. The device of heat and mass transfer provides continuous contact of stripped vapors with a stream of distant condensate, thereby maintaining the mass exchange between the vapor and liquid phases and freeing the flow of liquid product 44 from methane and lighter components.

The streams 32a and 33a are mixed in a mixing device and form a stream 31a, which enters the 118G separation section inside the processing unit 118, at a temperature of -32 ° P (-36 ° C) and a pressure of 900 psi. inch abs. (6203 kPa (a)), where the steam (stream 34) is separated from the liquid condensate (stream 35). The separation section 118G is separated from the demethanization section 118e by an internal partition or other means so as to enable these two sections to operate inside the processing installation 118 at different pressures.

Steam (stream 34) from separation section 118G is divided by the second separation device into two streams: stream 36 and stream 39. Stream 36, containing about 27% of steam from its total volume, is mixed in an additional mixing device with condensate separated in the separator (stream 35 through stream 37), and the resulting stream 38 is sent to a heat exchange device located in the bottom part of the raw material cooling section 118a inside the processing unit 118. A heat exchanger made of finned tubes can also be used as a heat exchange device, a plate heat exchanger, a brazed aluminum heat exchanger or a different type of heat exchangers, including multi-pass and / or multi-functional heat exchangers. The heat exchange device is designed to provide heat exchange between the stream 38 flowing through one stroke of the heat exchanging device and the stream of stripping steam rising from the separation section 118B, so that the stream 38 is cooled to full condensation while heating the stream of stripping steam.

The resulting condensed stream 38a at -138 ° P (-95 ° C) is then subjected to rapid evaporation through expansion valve 14 to an operating pressure (approximately 400 psi (2.758 kPa (a))) of the rectification section 118c (absorption unit) and an absorption section 1186 (another absorption device) located inside the processing installation 118. In the expansion process, part of the flow may evaporate, with the result that the main work flow is cooled. In the process method, which is illustrated in FIG. 2, the expanded stream 38b after the expansion valve 14 reaches a temperature of -139 ° P (-95 ° C) and is fed to the processing unit 118 between the rectification section 118c and the absorption section 1186. The condensate in the stream 38b is mixed with the condensate coming from the rectification section 118c, and all of the condensate is sent to absorption section 1186, the steam is mixed with the vapor coming from the absorption section 1186, and the resulting vaporous stream is sent to the rectification section 118c.

The remaining 73% of the volume of steam from the 118T section of separation (stream 39) is fed to the working expander 15, where the energy of this part of the raw material under high pressure is converted into mechanical. In the expander 15, the steam undergoes isentropic expansion to the operating pressure of the absorption section 1186, while the expanded stream 39a is cooled to a temperature of approximately -99 ° P (-73 ° C). The partially condensed expanded stream 39a is then fed as feed to the bottom part of the absorption section 1186 within the processing unit 118.

The recompressed and cooled stream of distant steam 41c is divided by the third separation device into two streams. One part, stream 46, is a volatile residual gas. The second part, the recycled stream 45, enters the heat exchange device in the cooling section of the raw material 118a, which is located inside the processing unit 118. A heat exchanger made of finned tubes, a plate heat exchanger, a brazed aluminum heat exchanger or another type of heat exchanger can also be used, including including multiport and / or multifunctional heat exchangers. The heat exchange device is designed to provide heat exchange between flow 45 flowing through one stroke of the heat exchanging device and the flow of distant steam rising from the separation section 118b, so that flow 45 is cooled to complete condensation, while heating the flow of distant steam.

The condensed recycled stream 45a leaves the heat exchanger in the cooling section of the raw material 118a, having a temperature of -138 ° P (-95 ° C) and undergoes rapid evaporation through the expansion valve 22 to the working pressure of the rectification section 118c located inside the processing unit 118. In the expansion process, part of the stream evaporates, causing the main workflow to cool. In the process method, which is illustrated in FIG. 2, the expanded stream 45b after the expansion valve 22 reaches a temperature of -146 ° P (-99 ° C) and is fed to the separation section 118b inside the processing unit 118. The liquid condensate separated here is sent to the distillation section 118c, and the remaining vapors are mixed with the steam rising from distillation section 118c, and form a stream of distant vapor, which is heated in the cooling section 118a.

Absorbing devices are installed in the rectification section 118c and in the absorption section 1186, which consist of several trays with gaps between them, one or several nozzles, or a combination of trays and nozzles. The trays and / or nozzles in rectification section 118c and in absorption section 1186 provide the necessary contact between the vapor rising and the cold condensate flowing down. The liquid component of the expanded stream 39a is mixed with the liquid condensate flowing down from the absorption section 1186, and the mixed condensate enters the liquid collecting device placed in the processing unit to ensure that the fluid continues to flow into the demethanization section 118e. The stripped vapors rising from the demethanization section 118e mix with the vapors from the expanded stream 39a and then rise to the absorption section 1186, where they come in contact with the cold condensate flowing down to condense and absorb the main volume of the C ₂ components, the C ₃ components, and more heavy components contained in these pairs. The vapors rising from the absorption section 1186 mix with the vapors from the expanded stream 38b and then rise to the rectification section 118c, where they come into contact with the cold part of the expanded stream 45b down to condense and absorb the main volume of the C ₂ , C ₃ and more components heavy components contained in these pairs. The liquid component of the expanded stream 38B is mixed with the liquid condensate flowing down from the rectification section 118c, and the mixed condensate continues to flow into the 118y absorption section.

The distant condensate flowing down from the heat and mass transfer device in the demethanization section 118e inside the processing installation 118 is freed from methane and lighter components. The resulting liquid product (stream 44) is removed from the bottom part of the demethanization section 118e and leaves the processing device 118 at a temperature of 65 ° P (18 ° C). The distant steam flow, rising from the separation section 118b, enters the steam collection unit located in the processing plant, and is then heated in the cooling section of the raw material 118a, while providing cooling streams 32, 38 and 45, as described earlier, and the resulting residual gas flow 41 leaves processing device 118 at a temperature of 105 ° P (40 ° C). Then, the flow of the distant vapor undergoes repeated compression in two stages: in the compressor 16, which is driven by the expander 15, and in the compressor 20, which is driven by an additional source of energy. After the stream 41B is cooled to 110 ° P (43 ° C) in the outlet cooler 21 and a stream 41c is formed, the recycled stream 45 is withdrawn from the device as previously described, forming a stream of residual gas 46, which then enters the sales pipeline under pressure 915 psi inch abs. (6307 kPa (a)).

Summary data on consumption and power consumption for the method shown in FIG. 2 are given in the following table. Ii.

Table II (Fig. 2). Flow data - lb-mol / h (kg-mol / h)

Flow Methane Ethane Propane Bhutan Total 31 12398 546 233 229 13726 32 8679 382 163 160 9608 35 234 51 59 157 513 36 3248 132 46 nineteen 3528 37 234 51 59 157 513 38 3482 183 105 176 4041 39 8916 363 128 53 9685 40 0 0 0 0 0 41 13863 thirty 0 0 14095 45 1475 3 0 0 1500 46 12388 27 0 0 12595 44 ten 519 233 229 1131

Dedicated components *

Ethane 95.03%

Propane 99.99%

Bhutan + 100.00%

Power

Compression of residual gas 5,787 hp [9.514 kW] * based on non-rounded flow rates

Comparison table. I and II show that the present invention allows to provide almost the same level of product extraction as the known technical solutions. However, further comparison of the indicators in the table. I and II shows that the same volume of the finished product was obtained at much lower energy consumption than in the installation, assembled using known technical solutions. Regarding the efficiency of product recovery (which is determined by the amount of ethane extracted per unit of power), the present invention is more than 6% more economical than the method using the known technical solutions shown in FIG. one.

Improving the efficiency of extraction of the product provided by the present invention compared with the method based on the known technical solutions (Fig. 1), mainly due to two factors. First, the compact layout of heat exchangers in the cooling section of the raw material 118a and heat and mass transfer devices in the demethanization section 118e of the processing installation 118 eliminates the pressure drop that occurs due to the presence of connecting piping in a conventional processing installation. As a result, in the installation made in accordance with the present invention, that part of the raw gas that enters the expander 15 is under a higher pressure than the gas in the installation collected using already known technical solutions; this allows the expander 15 in the scheme of the present invention to produce the same amount of energy at a higher output pressure, how much the expander 15 produces in the scheme using already known technical solutions, but with a lower output pressure. Consequently, the rectification section 118c and the absorption section 118y in the processing unit 118 of the present invention can operate under a higher pressure than the distillation column 18 in the scheme using already known technical solutions, while the level of product recovery remains the same. The result of increasing the working pressure and reducing the pressure drop due to the elimination of the connecting pipelines is that the distant steam enters the compressor 20 under much more

- 7 022763 high pressure, thus reducing the amount of energy needed to bring the residual gas pressure to the pressure level in the pipeline.

Secondly, the use of a heat and mass transfer device in the demethanization section 118e for simultaneous heating of the distant condensate leaving the absorption section 1186, while the steam obtained is able to contact with the condensate and release volatile components from it, which is more effective compared to using an ordinary distillation column with external reboilers. Volatile components are continuously released from the liquid condensate, thus their concentration in the stripped vapors decreases much faster, which increases the efficiency of distillation of light fractions for the present invention.

In addition to increasing the efficiency of processing, the present invention has two advantages over the current state of the art. First, the compact design of the processing plant 118 of the present invention replaces five separate pieces of equipment used in the conventional circuit (heat exchangers 10, 11 and 13; separator 12; distillation column 18 in FIG. 1) with one unit (processing plant 118 in FIG. 2). This reduces the area required for placement of the installation, as well as the connecting pipelines are eliminated, which leads to a decrease in capital costs for the processing plant, built according to the scheme of the present invention, compared to the installation, built using the already known technical solutions. Secondly, the exclusion from the design of connecting pipelines means that the processing plant, built according to the scheme of the present invention, has much less flange connections compared to the plant, built using already known technical solutions, which reduces the number of potential leaks in such a plant. Hydrocarbons are volatile organic compounds (VOS), some of which are classified as greenhouse gases, and some may create prerequisites for the formation of holes in the ozone layer; this means that the present invention reduces the possibility of emissions that pollute the atmosphere.

Other embodiments

In some cases, it may be necessary to feed a stream of liquid condensate 35 directly to the bottom part of the absorption section 1186 through stream 40, as shown in FIG. 2, 4, 6 and 8. In this case, an appropriate expansion device is used (for example, expansion valve 17), where the condensate expands to the operating pressure of the absorption section 1186, and the resulting expanded condensate stream 40a is fed as a raw material to the bottom part of the absorption section 1186 ( as shown by dashed lines). In some cases, it may be necessary to mix part of the condensate stream 35 (stream 37) with steam in stream 36 (Fig. 2 and 6) or with the cooled second stream 33a (Fig. 4 and 8) to form a combined stream 38 and direct the rest of the stream condensate 35 to the bottom part of the absorption section 1186 in streams 40 / 40a. In some cases, it may be necessary to mix the expanded condensate stream 40a with the expanded stream 39a (Fig. 2 and 6) or the expanded stream 34a (Fig. 4 and 8), then feed the combined stream to the bottom part of the absorption section 1186 as a raw material.

If the residual gas is enriched, the amount of condensate separated into stream 35 may be sufficient to accommodate the additional mass transfer zone in the demethanization section 118e between the expanded stream 39a and the expanded condensate stream 40a, as shown in FIG. 3 and 7, or between the expanded stream 34a and the expanded condensate stream 40a, as shown in FIG. 5 and 9. In this case, the heat and mass transfer devices in the demethanization section 118e can be installed in the top and bottom parts, so that the expanded condensate stream 40a can be supplied between them. The dashed lines show that in some cases it may be necessary to mix part of the condensate stream 35 (stream 37) with steam in stream 36 (Fig. 3 and 7), or with the second cooled part of stream 33a (Fig. 5 and 9) to form the combined stream 38, while the remainder of the condensate stream 35 (stream 40) expands to a lower pressure and is supplied between the top and bottom parts of the heat and mass transfer device in the de-methanization section 118e as stream 40a.

In some cases, it may be necessary not to mix the cooled first and second parts (streams 32a and 33a), as shown in FIG. 4, 5, 8 and 9. In this case, the cooled first part 32a is sent to the separation section 118G in the processing installation 118 (Fig. 4 and 5), or to the separator 12 (Fig. 8 and 9), where steam (stream 34) separated from liquid condensate (stream 35). The steam flow 34 enters the expander 15, where it undergoes isentropic expansion to the working pressure of the absorption section 1186, after which the expanded flow 34a is fed as raw material to the bottom part of the absorption section 1186 located inside the processing unit 118. The cooled second part of the flow 33a is mixed with the separated the condensate separator (stream 35 through stream 37), and the combined stream 38 is sent to the heat exchange device in the bottom part of the raw material cooling section 118a in the processing unit 118, where it is cooled to full oh condensation. The condensed stream 38a is then subjected to rapid evaporation through the expansion valve 14 to the operating pressure of the distillation section 118c and the absorption section 1186, after which the expanded stream 38b is fed to

- 8 022763 processing unit 118 to the zone between the distillation section 118c and the absorption section 1186. In some cases, it may be necessary to mix only part (stream 37) of the condensate stream 35 with the cooled second part — stream 33a, and the rest (stream 40) the bottom part of the absorption section 1186 through the expansion valve 17. In another case, it may be necessary to direct the entire flow of condensate 35 to the bottom part of the absorption section 1186 through the expansion valve 17.

In some cases, it may be necessary to use an external tank for separating the cooled raw material stream 31a or the cooled first part - stream 32a, instead of including the separator section 118G in the processing unit 118. As shown in FIG. 6, 7, 14, and 15, the separator 12 can be used to separate the cooled feed stream 31a into a stream of steam 34 and a stream of condensate 35. Also, as shown in FIG. 8, 9, 16 and 17, the separator 12 can be used to separate the cooled portion of the stream 32a into a stream of steam 34 and a stream of condensate 35.

Depending on the amount of heavy hydrocarbons in the feed gas and on the pressure of its supply, the cooled feed stream 31a entering the separation section 118G, as shown in FIG. 2 and 3, or to a separator 12, as shown in FIG. 6 and 7 (or the cooled first part of the stream 32a entering the separation section 118G, as shown in Fig. 4 and 5, or into the separator 12, as shown in Fig. 8 and 9) may not contain a liquid component (since the pressure exceeds the point of onset of condensation or cricondenbara). In such cases, there is no condensate in streams 35 and 37 (as shown by dashed lines), so that only steam from separation section 118G in stream 36 (Fig. 2 and 3), steam from separator 12 in stream 36 (Fig. 6), or the cooled second portion of stream 33a (FIGS. 4, 5, 8, and 9) flow into stream 38; This stream is transformed into an expanded condensed stream 38b entering the processing unit 118, into the zone between the distillation section 118c and the absorption section 1186. In this case, the separation section 118G in the processing unit 118 (Fig. 2-5) or separator 12 (Fig. 6 -9) may not be needed.

The characteristics of the raw gas, the dimensions of the installation, the existing equipment or other factors may indicate that the expander 15 is not required to be installed, or it must be replaced with another expansion device (for example, an expansion valve). Although the diagram shows specific expansion devices for each stream, if necessary, other devices can be used instead. For example, the processing mode requires the expansion of the fully condensed portion of the feed stream (stream 38a) or the fully condensed recycled stream (stream 45a).

In accordance with the present invention, it is possible to use an external cooling unit for additional cooling of the incoming gas entering the streams of distant steam and condensate, especially if an enriched incoming gas is used. In such cases, the heat and mass transfer device can be included in the 118G separation section (or install a steam collector for gas collection if the cooled feed stream 31a or the cooled first part of stream 32a does not contain a liquid component), as shown by dotted lines in FIG. 2-5; Alternatively, the heat and mass transfer device can be incorporated into the separator 12, as shown by the dotted lines in FIG. 6-9. A heat exchanger made of finned tubes, a plate heat exchanger, a brazed aluminum heat exchanger or a different type of heat exchanging device, including multi-way and / or multi-functional heat exchangers, can be used as a device for heat and mass transfer. The heat exchange device is designed to provide heat exchange between the flow of refrigerant (for example, propane) flowing through one heat-exchanger device and the vaporous part of the stream 31a (Fig. 2, 3, 6 and 7) or the stream 32a (Fig. 4, 5, 8 and 9), which move in the upward direction, while the refrigerant cools the steam and promotes the formation of additional condensate, which flows down and combines with the condensate removed from the stream 35. Alternatively, it is possible to use conventional gas coolers to lower those the temperature of stream 32a, stream 33a and / or stream 31a with the aid of a refrigerant before stream 31a enters section 118G of separation (Fig. 2 and 3) or into separator 12 (Fig. 6 and 7); either the stream 32a enters the separation section 118G (Fig. 4 and 5) or into the separator 12 (Fig. 8 and 9).

Depending on the temperature and the degree of enrichment of the raw gas, as well as on the amount of C ₂ components that need to be removed from the liquid product stream 44, heating only due to stream 33 may not be enough for the condensate leaving the demethanization section 118e to meet product characteristics. In this case, additional means of heating with heat carrier can be installed in the heat and mass transfer device in the demethanization section 118e, as shown by dotted lines in FIG. 2-9. Alternatively, it is possible to install another heat and mass transfer device in the bottom part of the demethanization section 118e to provide additional heating; Either the stream 33 can be heated with the help of a heat transfer medium before it enters the heat and mass transfer device installed in the demethanization section 118e.

Depending on the type of heat transfer devices selected as heat exchangers for the upper and bottom parts of the raw material cooling section 118a, it is possible to combine these heat exchangers into one multi-pass and / or multi-functional heat exchanger. In this case, the multiple and / or multifunctional heat exchanging device must have appropriate means for distributing, separating and collecting the stream 32, the stream 38, the stream 45, and also the stream of stripping steam for heating or cooling to the desired level.

In some cases, it may be necessary to install an additional mass transfer device in the upper part of the demethanization section 118e. In this case, the mass transfer device can be placed below the feed point of the expanded stream 39a (Fig. 2, 3, 6 and 7) or the expanded stream 34a (Fig. 4, 5, 8 and 9) in the bottom part of the absorption section 1186 and above the cooled exit point the second part of the stream 33a from the heat and mass transfer device in the demethanization section 118e.

Less preferred for the embodiments of the present invention shown in FIG. 2, 3, 6 and 7, is the installation of a separator for the cooled first part of the stream 31a, a separator for the cooled second part of the stream 32a; however, the steam streams separated in the separators mix to form a steam stream 34, and the condensate streams mix and form a condensate stream 35. Another less preferred embodiment of the present invention is to cool the stream 37 in a separate heat exchanger located in the cooling section of the feed 118a ( instead of mixing stream 37 with stream 36 or stream 33a to form a combined stream 38); however, the expansion of the cooled stream is performed in a separate expansion device, and the expanded stream is fed into the intermediate zone of the absorption section 1186.

It should be noted that the relative amount of raw materials in each outlet of the separated vaporous raw materials depends on several factors, including the pressure and composition of the raw gas, the amount of heat that can be extracted from the raw material, as well as the available amount of power. An increase in the feed to the zone above the absorption section 1186 may lead to an increase in the degree of product extraction while reducing the power obtained in the expander, which, in turn, leads to an increase in the power required to recompress the product. Increasing the feed to the zone below the absorption section 1186 reduces the level of power consumed, but it can also lower the level of product recovery.

The present invention provides an increased degree of extraction of components of C ₂ , C ₃ and heavier hydrocarbons, or components of C ₃ and heavier hydrocarbons for the amount of auxiliary media consumed necessary for the operation of the method. Saving consumable auxiliary media necessary for the operation of the method can manifest itself in the form of reduced power consumption for compression or recompression; reducing the power required for an external cooling installation; reduce the energy required for additional heating; or in the form of their combination.

Here is a description of preferred embodiments of the invention; Specialists with an appropriate level of technical training may find other options or make changes to those described here (for example, to adapt the invention to work in other modes using a different type of raw material or changing other requirements), without deviating from the essence of the present invention, defined in the following formula .

Claims (25)

CLAIM (1) a steam collection device is placed in said processing unit 118 in a separator section 118G; (1) the specified heat and mass transfer device is installed in the upper and lower parts of the demethanization section 118e; (1) the specified heat and mass transfer device is installed in the upper and lower parts of the demethanization section 118e; 1. A method for separating a gas stream 31 containing methane, components C ₂ , components C ₃ and heavier hydrocarbon components, into a volatile fraction of residual gas 46 and a relatively less volatile fraction 44 containing the bulk of these components C2, components C3 and heavier hydrocarbon components, or these components C3 and heavier hydrocarbon components, where (1) the specified gas stream 31 is divided into the first 32 and second 33 parts; (2) the specified vapor stream is sent to the specified additional heat and mass transfer device for cooling it using the specified external cooling agent with the formation of additional condensate; and (3) said condensate is mixed with at least one condensate stream 35 separated by separation. (2) an additional heat and mass transfer device is placed inside said steam collection device, said additional heat and mass transfer device includes one or more channels for an external cooling agent; (2) an additional heat and mass transfer device is placed inside said steam collection device, said additional heat and mass transfer device includes one or more channels for an external cooling agent; (2) a heat exchange device located in the processing unit 118 in the cooling section 118a of the feedstock and connected to said first separation device for receiving and cooling said first part of stream 32 to produce a cooled first part of stream 32a; (2) said vapor stream from step (b) is sent to said additional heat and mass transfer device for cooling with an external cooling agent to form additional condensate; and (3) said condensate is mixed with at least one condensate stream 35 from step (b) separated by separation. (2) an additional heat and mass transfer device is placed inside said steam collecting device for gas separation in the separator section 118G, wherein said heat and mass transfer device has one or more channels for passing an external cooling agent; (2) an additional heat and mass transfer device is placed inside the specified steam collection device in the separator section 118G, while the specified heat and mass transfer device has one or more channels for passing an external cooling agent; (2) said expanded at least a portion of said at least one condensate stream 40a from step (s) is supplied to said processing unit 118, into the space between said upper and lower parts of said heat and mass transfer device in said demethanization section 118e. (2) said expanded at least a portion of said at least one condensate stream 40a from step (s) is supplied to said processing unit 118, into the space between said upper and lower parts of said heat and mass transfer device in said demethanization section 118e. 2. The method according to claim 1, where: (a) said chilled first portion of stream 32a from step (4) is mixed with said chilled second portion of stream 33a from step (4), thereby forming a partially condensed gas stream 31a; (b) said partially condensed gas stream 31a is supplied to a separation device 12, where it is separated into a vapor stream 34 and at least one condensate stream 35; (c) said vapor stream 34 is divided into said first 36 and said second 39 streams; and (6) at least a portion 40 of said at least one condensate stream 35 is expanded in the expansion device 17 to a lower pressure and then fed as an additional feed stream 40a to the still part of said second absorption device 1186. (2) said first portion of stream 32 is cooled in cooling section 118a; (3) said steam collection device is connected to said heat exchange device for receiving a cooled first portion of the stream 32a and its direction to said additional heat and mass transfer device for additional cooling using said external cooling agent; and (4) the second expansion device 15 is connected to the specified steam collection device for receiving the specified additionally cooled first part of the stream 34 and its expansion to the specified lower pressure to obtain a stream 34a, where the specified second expansion device 15 is additionally connected to the specified second absorption device 118ά for supplying an additionally cooled expanded first part of the stream 34a to its bottom part as a raw material. (3) said steam collection device is connected to a mixing device for receiving said cooled gas stream 31a and for sending it to an additional heat and mass transfer device for additional cooling using an external cooling agent; and (4) said second separation device is connected to said steam collection device for receiving said further cooled gas stream 34 and for separating it into first 36 and second 39 streams. (3) a heat and mass transfer device installed in said processing unit 118 in a demethanization section 118e and connected to said first separation device for receiving and cooling said second part of stream 33 to produce a cooled second part of stream 33 a; (3) said cooled first portion of stream 32a from step (a) is supplied to said steam collection device in separator section 118G and sent to said additional heat and oil exchange device for additional cooling using said external cooling agent; and (4) said further cooled first portion of stream 34 is expanded in expansion device 15 to the specified lower pressure and then fed as feedstock 34a to the still portion of second absorption device 1186. (3) said cooled gas stream 31a from step (4) is supplied to said steam collection device in separation section 118G and sent to said additional heat and mass transfer device for additional cooling with an external cooling agent; and (4) said further cooled gas stream 34 is divided into first 36 and second 39 streams. 3. The method according to claim 2, where: (a) said first stream 36 from step (c) is mixed with at least a portion 37 of said at least one condensate stream 35 from step (b) to form a combined stream 38; (b) said combined stream 38 is cooled in the cooling section 118a until it is substantially completely condensed to give stream 38a, and then expanded in expansion device 14 to a lower pressure, thereby further cooling stream 38b; (c) said expanded cooled combined stream 38b as said feed is fed into the zone between said first 118c and second 1186 absorption devices; and (6) any remaining portion 40 of said at least one condensate stream 35 from step (b) is expanded in the expansion device 17 to a lower pressure, and the resulting stream 40a is supplied as additional raw material to the bottoms of said second absorption device 1186. (3) said second portion of stream 33 is cooled in demethanization section 118e; (4) a mixing device connected to said heat exchanger device and heat and mass transfer device and for receiving the cooled first 32a and second parts of the stream 33a and the formation of the cooled gas stream 31a, 34; 4. The method according to claim 1, where: (a) said first portion of stream 32 from step (2) is cooled in cooling section 118a and then expanded in expansion device 15 to a lower pressure to obtain expanded and cooled stream 34a; (b) said second part of stream 33 from step (3) is cooled in a heat and mass transfer device located in demethanization section 118e and in cooling section 118a, until it is substantially condensed to obtain stream 38a and then expanded in expansion device 14 to lower pressure, thereby further cooling the 38b stream; (c) said expanded chilled second portion of stream 38b as said feed (4) said chilled first stream portion 32a is mixed with said chilled second stream portion 33a, thereby forming a chilled gas stream 31a, 34; (5) a second separation device connected to said mixing device for receiving a cooled gas stream 31a, 34 and separating the cooled gas stream into first 36 and second 39 streams; 5. The method according to claim 4, where: (a) said first portion of stream 32 from step (2) is cooled sufficiently in the cooling section 118a until it partially condenses to produce stream 32a; (b) said partially condensed first portion of stream 32a is fed to a separation device 12, where it is separated into a vapor stream 34 and at least one condensate stream 35; (c) said vapor stream 34 is expanded in the expansion device 15 to the specified lower pressure and supplied as said first feed stream 34a to the bottom part of said second absorption device 118y; (i) at least a portion 40 of the at least one condensate stream 35 is expanded in the expansion device 17 to the specified lower pressure and supplied as an additional feed stream 40a to the still part of the specified second absorption device 118y. (5) said cooled gas stream 31a, 34 is divided into first 36 and second 39 streams; (6) said first 118c and second 1186 absorption devices connected to said first expansion device 14 and designed to receive said expanded and cooled combined stream 38b fed as said raw material into the zone between said first 118c and second 1186 absorption devices; and (e) said fourth expansion device 17 connected to said separation device 12, for receiving any remaining portion 40 of said at least one condensate stream 35 and expanding it to said lower pressure to obtain a stream 40a where said fourth expansion the device 17 is additionally connected to the specified second absorption device 1186 for supplying the specified expanded stream of condensate 40A in its bottom part as additional raw materials. (6) a fourth expansion device 17 connected to a separation device 12 for receiving at least a portion 40 of said at least one condensate stream 35 and expanding it to said lower pressure to obtain a stream 40a, wherein said fourth expansion device 17 additionally connected to the specified second absorption device 1186 for supplying the specified expanded stream of condensate 40A in its bottom part as additional raw materials. (6) said heat exchanger, further connected to a second separation device, for receiving and cooling sufficiently said first stream 36, 38 until it substantially condenses to form stream 38a; 6. The method according to claim 5, where: (a) said second part of stream 33 is cooled in a heat and mass transfer device located in demethanization section 118e, and then mixed with at least part 37 of said at least one condensate stream 35 from step (b), forming a combined stream 38; (b) said combined stream 38 is cooled in the cooling section 118a to substantially completely condensate to obtain stream 38a and then expanded in expansion device 14 to a lower pressure, thereby further cooling stream 38b; (c) said expanded cooled combined stream 38b, as said feed, is fed into the zone between said first 118c and second 118th absorption devices; and (i) any remaining portion 40 of said condensate stream 35 from step (b) is expanded in the expansion device 17 to a lower pressure and then fed as additional raw material 40a to the bottoms of said second absorption device 118y. (6) said first stream 36, 38 is cooled in the cooling section 118a until it is substantially completely condensed to obtain stream 38a and then expanded in expansion device 14 to a lower pressure to obtain an additionally cooled stream 38b; (7) a first expansion device 14 connected to said heat exchanger to receive and expand the substantially condensed first stream 38a to a lower pressure to produce an additionally cooled stream 38b; 7. The method according to claim 2 or 5, where: (7) said expanded cooled first stream 38b is fed as feed into the zone between the first 118c and second 1186 absorption devices installed in the processing unit 118, including the cooling section 118a of the feedstock, the separation section 118b, the distillation section 118c, the absorption section 1186 and the demethanization section 118e; wherein said first absorption device 118c is positioned in the distillation section 118c above said second absorption device 1186 in the absorption section 1186; (8) the first 118c and second 1186 absorption devices located in the specified processing unit 118, connected to the specified first expansion device 14 and designed to receive the specified expanded and cooled first stream 38b, served as raw material in the area between the specified first 118c and second 1186 absorption devices, wherein said first absorption device 118c is located in the distillation section 118c above said second absorption device 1186 in the absorption section 1186; 8. The method according to claim 3 or 6, where: (8) said second stream 39 is expanded in the expansion device 15 to a lower pressure and is supplied as feedstock 39a to the bottoms of said second ab-10 022763 sorption device 1186; (9) a second expansion device 15 connected to said second separation device for receiving and expanding the second stream 39 to said lower pressure to obtain a stream 39a, and further connected to said second absorption device 1186 for supplying said expanded second stream to its bottom part as a feed stream 39a; 9. The method according to any one of claims 2, 3, 5, 6, 7 or 8, where the separation device is placed in the specified processing unit 118 in the separator section 118G. (9) the stripping steam stream from the top of said first absorption device 118c is collected in a steam collector of the separator section 1186 and heated in the cooling section 118a in a heat exchanger, and said heated stripping vapor stream 41 is removed from said processing unit 118; (10) a steam collection device in the separator section 118b located in the processing unit 118, connected to the first absorption device 118c and designed to receive a stream of stripping steam coming from the top of said first absorption device 118c; 10. The method according to claim 1, where: (10) said heated stripping vapor stream 41 is compressed in a compressor 16, 20 to a higher pressure to obtain streams 41a, 41b, which are cooled in a cooling device 21, to obtain a stream 41c, and then separated into a volatile fraction of residual gas 46 and compressed recycled stream 45; (11) the specified heat transfer device, additionally connected to the specified steam collection device and designed to receive and heat the specified stream of stripping steam, thus, at least partially contributing to the cooling of the flows in stages (2) and (6) of the method according to claim 1, and outputting the heated stream of stripping steam 41 from said processing unit 118; 11. The method according to claim 4, where (1) the steam-collecting device is placed in the specified processing unit 118 in the separator section 118G; - 11 022763 served in the area between the specified first 118C and second 118b absorption devices; (i) said expanded and cooled first portion of stream 34a is supplied as said feedstock to a still portion of said second absorption device 118y. (11) said compressed recycle stream 45 is cooled in the cooling section 118a until it is substantially completely condensed into a substantially condensed compressed recycle stream 45a; (12) a compressor device 16, 20 connected to said processing unit 118 for receiving a heated stream of stripping steam 41 and compressing it to a higher pressure to obtain streams 41a, 41b; 12. The method according to claims 2, 3, 5, 6, 7, 8, or 9, where (1) an additional heat and mass transfer device is placed inside the separation device 12 or separator section 118G, wherein said heat and mass transfer device has one or more channels for external cooling an agent; (12) said substantially condensed compressed recycle stream 45a is expanded in expansion device 22 to said lower pressure and fed as feed 45b to the top of the first absorption device 118c; - 13,022,763 designed to receive a cooled compressed stream of stripping vapor 41c and separating it into a volatile fraction of residual gas 46 and compressed recycled stream 45; (13) a cooling device 21 connected to said compressor device 20 for receiving said compressed stream of stripping vapor 41b and cooling it; 13. The method according to claims 1-12, where the specified heat and mass transfer device located in the demethanization section 118e includes one or more channels for an external coolant to maintain the temperature provided by the second part of stream 33 and which is sufficient to separate more volatile components from the specified distant stream condensate. (13) the specified heating of the specified stream of distant steam is carried out in one or more heat exchangers placed in the specified processing unit 118 in the cooling section 118a, thus providing at least partial cooling in stages (2), (6) and (11 ); - 14,022,763 (14) a third separation device connected to said cooling device 21 and 14. The device for performing the method according to claim 1, comprising (1) a first separation device for separating the gas stream 31 into the first 32 and second 33 parts; (14) the distillate condensate stream is collected from the bottom part of said second absorption device 1186 and heated in a heat and mass transfer device located in said processing unit 118 in the demethanization section 118e, thereby providing at least partial cooling in step (3), while more volatile components are simultaneously released from the specified stripping condensate stream, after which the specified heated and purified from light fractions stripping condensate stream is removed from the processing plant as TBE relatively less volatile fraction 44; and (15) the amount and temperature of said feed streams 45b, 38b, 39a, sent to said first absorption device 118c and second 1186, is sufficient at said upper part of said first absorption device 118c to extract a majority of the components from said stream into said relatively less volatile fraction 44. - 15,022,763 the upper and lower parts of the specified heat and mass transfer device in the specified section demethanization 118th. 15. The device according to 14, including: (a) said mixing device connected to said heat exchange device and to said heat and mass transfer device and adapted to receive cooled first part of stream 32a and second part of stream 33a and form a partially condensed gas stream 31a; (b) a separation device 12 connected to said mixing device and adapted to receive a partially condensed gas stream 31a and separate it into a vapor stream 34 and at least one condensate stream 35; (c) said second separation device coupled to said separation device 12 and adapted to receive said vapor stream 34 and separate it into said first 36 and second 39 streams; and (i) a fourth expansion device 17 connected to said separation device 12 for receiving at least a portion 40 of said at least one condensate stream 35 and expanding it to said lower pressure, and said fourth expansion device 17, further connected with the specified second absorption device 118y for supplying an expanded stream of condensate 40a in its bottom part as additional raw materials. (15) said heat exchange device further connected to said third separation device for receiving said compressed recirculated stream 45 and cooling it sufficiently to substantially completely condense it to obtain stream 45a, thereby providing at least partial heating the stream in step (11) of the method according to claim 1; 16. The device according to clause 15, including: (a) an additional mixing device connected to a second separation device and a separation device 12 for receiving said first stream 36 and at least a portion 37 of said at least one condensate stream 35 and forming a combined stream 38; (b) said heat exchange device further connected to said additional mixing device for receiving said combined stream 38 and cooling it sufficiently to substantially completely condense to produce stream 38a; (c) said first expansion device 14 connected to said heat exchanger for receiving said substantially fully condensed combined stream 38a and expanding it to a lower pressure stream 38b; (i) said first 118c and second 118th absorption device connected to the first expansion device 14 and designed to receive said expanded and cooled combined stream 38b fed as said raw material into the zone between said first 118c and second 118th absorption device; and (e) said fourth expansion device 17 connected to said separation device 12, for receiving any remaining portion 40 of said at least one condensate stream 35 and expanding it to said lower pressure to obtain a stream 40a where said fourth expansion the device 17 is additionally connected to the specified second absorption device 118y for supplying an expanded stream of condensate 40a to its bottom part as additional raw materials. (16) a third expansion device 22 connected to said heat exchanger and adapted to receive said substantially condensed compressed recycled stream 45a and expand it to said lower pressure to produce stream 45b, wherein said third expansion device 22 is further connected with said first absorption device 118c for supplying said expanded recirculated stream 45b to its upper part as a raw material; 17. The device according to 14, including: (a) said heat exchange device further connected to said heat and mass transfer device and adapted to receive said cooled second portion of stream 33a, 38 and further cool it sufficiently to substantially complete condensation to produce stream 38a; (b) said first expansion device 14 connected to said heat exchange device and adapted to receive a substantially fully condensed second portion of stream 38a and expand to a lower pressure to produce stream 38b; (c) said first 118c and second 1186 absorption devices connected to said first expansion device 14 and adapted to receive said expanded and cooled second portion of stream 38b fed as said raw material into the area between said first 118c and second 1186 absorption devices; and (6) said second expansion device 15 connected to said heat exchanger, for receiving said cooled first portion of stream 32a, 34 and expanding it to said lower pressure, to obtain stream 34a, where said expansion device 15 is further connected to said a second absorption device 1186 for supplying the expanded cooled first portion of the stream 34a to its bottom portion as said feedstock. (17) a condensate collecting device disposed in the processing unit 118, connected to said second absorption device 118y and intended to receive a stream of distillation condensate coming from the bottom part of said second absorption device 118y; 18. The device according to 17, including: (a) said heat exchanger connected to a first separation device and adapted to receive said first portion of stream 32 and cool it sufficiently to partially condensate it to produce stream 32a; (b) a separation device 12 connected to said heat exchanger and adapted to receive said partially condensed first portion of stream 32a and to separate it into vapor stream 34 and at least one condensate stream 35; (c) said second expansion device 15, connected to said separation device 12, for receiving the vapor stream 34 and expanding it to said lower pressure, to obtain a stream 34a, where said expansion device 15 is further connected to said second absorption device 1186 for feeding the expanded vapor stream 34a into its bottom part as said primary feed; (18) said heat and mass transfer device, further connected to said condensate collecting device, is for receiving and heating said stream of distant condensate, thereby at least partially contributing to cooling in step (3) of the method according to claim 1, wherein from the distillate stream more volatile components are simultaneously released from the condensate, after which the specified distilled condensate stream heated and freed from light fractions is removed from the processing unit 118 as a relatively less volatile fractions 44; and (19) a control device for controlling the amount and temperature of said feed streams 45b, 38b, 39a directed to said first absorption device 118c and second 118th, to maintain the temperature in said upper part of said first absorption device 118c at a level at which the bulk of the components is recovered from the stream into said relatively less volatile fraction 44. 19. The device according to p, including: (a) an additional mixing device connected to said heat and mass transfer device and separation device 12 and for receiving a cooled second part of stream 33a and at least part 37 of said at least one condensate stream 35 and forming a combined stream 38; (b) said heat exchange device, further connected to said additional mixing device for receiving the combined stream 38 and cooling it sufficiently to substantially completely condense to produce stream 38a; (c) said first expansion device 14 connected to said heat exchanger and adapted to receive the substantially fully condensed combined stream 38a and expand it to a lower pressure to produce stream 38b; 20. The device according to claims 15, 16, 18 or 19, where (1) said heat and mass transfer device is installed in the upper and lower parts of the demethanization section 118e; and (2) said processing unit 118 is connected to a fourth expansion device 17 for receiving said expanded condensate stream 40a and directing it to the area between 21. The device according to PP.15, 16, 18, 19 or 20, where the separation device is located in the specified processing unit 118 in the separator section 118G. 22. The device according to 14, where (1) the steam-collecting device is located in the specified processing unit 118 in the separator section 118G; 23. The device according to 17, where (1) the steam-collecting device is located in the specified processing unit 118 in the separator section 118G; 24. The device according to claims 15, 16, 18, 19, 20 or 21, where (1) an additional heat and mass transfer device is located inside the separation device 12 or separation section 118G, said additional heat and mass transfer device includes one or more channels for an external cooling agent; 25. The device according to PP.14, 15, 16, 17, 18, 19, 20, 21, 22, 23 or 24, where the specified heat and mass transfer device includes one or more channels for an external coolant to maintain the temperature provided by the second part of the stream 33 and which is sufficient to separate more volatile components from the specified stream of distant condensate.