SA07280532B1 - hydrocarbon gas processing - Google Patents

Abstract

Abstract This invention relates to a process and apparatus for recovering ethane, ethylene, propane, propylene, and heavier hydrocarbon components from a hydrocarbon gas stream. The stream is cooled and divided into first and second streams. The first stream is also cooled to condensate it all to a great extent and then expands to pressurize the fractionation tower and is passed to the fractionation tower at the feed position first center of the column. The second current is extended to the tower pressure and then passed to the column at a second feed position in the center of the column. The distillation stream is drawn from the column below the feed point of the second stream and pressurized to a higher pressure, then directed in a heat exchange relationship with the overhead vapor stream of the tower to cool the distillation stream and condense it entirely to form a combined stream. At least part of the condensate current is directed to the retail tower as its top feed charge. The quantities and temperatures of the feed shipments to the fragmentation tower are effective to keep the upper temperature of the fragmentation tower at a temperature by which the bulk of the desired components are retrieved. In other embodiments, the distillation stream is drawn from the column above the point of the second stream feed.

Description

¥ hydrocarbon gas processing Full description Background: Ethylene LEN! can be extracted; ethane ¢ propylene; propane » and/or heavier hydrocarbon components 168,716 from a different group of gases; Jie streams of natural gas, natural gas; Gases produced from refining gas; Synthetic gas obtained from other hydrocarbon materials Jia coal; crude oil ¢ naphtha ; oil shale ¢ tar sands; And lignite. Natural gas may usually contain a large proportion of methane and ethane. 0 i.e.; Methane and ethane together contain at least 00 mole percent of the gas. Lad gas contains relatively smaller amounts of lesser hydrocarbons such as propane “butanes” and “pentanes” and the like; such as hydrogen + nitrogen, carbon dioxide; And other gases. 0 GENERAL DESCRIPTION OF THE INVENTION: This invention generally relates to the extraction of ethylene “ethane” propylene “propane” and hydrocarbons heavier than these (SLs) streams. There is a typical analysis of a gas stream to be treated as a lida for this invention; YY oA v

in an approximate molar percentage; 740.8 methane 4.1 «methane 7 ethane ethane» and components

© other; IVY propane and other © ingredients “E) iso-butane “Lax # ¢ normal butane 7 pentanes” and 77.1 carbon dioxide Nitrogen makes up the rest. It also exists

Other gases sometimes contain sulfur.

Cyclical changes over time result in the prices of both natural gas

natural gas and its natural gas liquid (NGL) components sometimes to incremental Aad reduction of ethane; ethylene; Propane “propylene” and heavier components as liquid products. This led to a need for processes that could provide

0 extracts more efficient from these outputs; processes that can provide more efficient extractions at lower total and operating costs; And processes that Al spy can configure or set to change the extraction of a particular component over a wide range. Available processes for separating these materials include gas cooling; oil absorption; Absorb the oil that has been cooled

. In addition ; Alle refrigeration processes have become preferred due to availability

0 _ Economical equipment that produces energy while at the same time working on expansion and extracting heat from the gas to be treated. And depending on the pressure of the gas source -

how much enrichment (City) ethane; ethylene and heavier hydrocarbons) in gas; desired end products; Either or both of these processes may be used

union thereof. © The cryogenic expansion process is now generally preferred for the extraction of gaseous liquid recovery fluids because it provides maximum simplicity with ease of start-up; YYoA flexibility

¢

in operation; good efficiency; Safety ; And good reliability. And US patents show No. B Ah Al-Malaklat 014 45464 / M2 01764 6 H M 4 4 Katalha (Al-Amklatha) BLAMK LIVING CUT 4 LAMPS # STRIPPED 0 ELATALVE.

E.A06.400 (© Meem km); 10,09A.YYY 0.000.Y(A ;0.YVO...0) 7 No, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no, no. No. 408; and Absolute Patent Application No. 11/470,417 involved processes (although in some cases the full description of this invention is Ming

0 on process conditions different from those (anal in the above-mentioned patents and applications). In a typical cryogenic expansion process; A stream of charge gas under pressure is cooled by heat exchange with other streams from the process and/or external sources of refrigeration Jie propane-cooling compressor. When the gas is cooled, the liquids may be condensed and collected in one or more Vo separation units as high-pressure liquids containing some desirable Cot or Cat components (Led). And depending on the extent of the gas enrichment and the amount of liquids formed; Liquids Ale pressure Ale may be expanded to J pressure and fractionated. The evaporation present during the expansion of the liquids leads to additional cooling, Lal, and under the same conditions; It may be desirable for the purpose of reducing the temperature generated by expansion. The expanding current 0 is split; containing a mixture of liquid and vapor in a distillation column (methane removal unit or ethane removal unit) and in the column; distillation is

lal(at) refrigerant (3) expanded (3) to separate residual methane; nitrogen; and other volatile gases5 as top vapor from the “Cp” components, ©; and the heavier hydrocarbon components desired as bottom liquid product 0 or to separate the residual methane; components Cp; nitrogen + and other volatile gases as top© vapor from the ingredients:© and the heavier hydrocarbon components desired as bottom liquid product. If the charge gas is not fully condensed (le) preferably not intensified); Part of the vapor remaining from the partial condensation may be passed through an expansion machine or motor; or expansion valve; To a pressure JB at which additional fluid is condensed 0 as a result of the additional cooling of the system. The pressure after expansion is exactly the same as the pressure at which the distillation column is operated. The combined vapor-liquid phase resulting from expansion is supplied as a charge to the column. and the remaining part of the vapor is cooled to the primary cooling by heat exchange with other process streams; for example daw; The upper part of the 01 cold retail tower. Some or all of the high-pressure liquid may be combined with this vapor portion prior to cooling. The resulting coolant stream is then expanded through a suitable expansion device; such as an expansion valve » to the pressure at which the demethane unit (ual) is actuated. During expansion a part of the liquid will be vaporized, producing ae cooling of the total current. The flash expanding current is then supplied as an overhead charge 0 to De-methane unit Typically, the vapor portion of the expanding stream and the upper steam from the de-methane unit are combined in the upper separation zone of the YYoA distillation tower.

Fractional catalyst produced from residual methane. as an alternative; The cooled and expanding stream may be supplied to the separator to provide vapor and liquid streams. The steam is combined with the upper stream of the tower and the liquid is supplied to the column as an upper column charge. And in the perfect operation of that separation process; The waste gas leaving the Lila process will contain all the methane in the charge gas and without the heavier hydrocarbon components and the bottom distillate leaving the demethanation unit will contain all the heavier hydrocarbon components and absolutely no methane or other volatile components . practically 0 in any case; This ideal state is not reached for two main reasons. The first reason is that a conventional de-methane unit is characterized by its operation largely as a column extraction (removal of light oil fractions or removal of volatile components). It includes the methane output of the process; thereby preferably on vapors leaving the column's upper fractional distillation stage; Together with the vapors that are not exposed to any refining step. The large loss of Cys Cob components occurs because the upper liquid charge contains large quantities of these components and the heavier hydrocarbon 1 components; This results in dle producing corresponding equilibrium quantities of the Cyt components and the +,© components ; And the lower hydrocarbon components in the vapors leaving the fractional distillation stage (App all) from the methane removal unit. The loss of these desirable components can be greatly reduced if the escaping vapors can be brought into contact with a large amount of liquid (reflux) capable of absorbing © components: © and components ,©; The hydrocarbon components heavier than the vapors.

No, and the second reason that this ideal state cannot be reached is that the carbon dioxide present in the charge gas distillation products in the methane removal unit can reach large concentrations, for example, 75 to 101 or more in the distillation tower until When the charge gas contains less than 71 carbon dioxide. At such high concentrations 6 formation of solid carbon dioxide can occur depending on the temperatures; Pressures » and liquid solubility. It is well known that natural gas streams usually contain carbon dioxide; Sometimes in large quantities. and if the concentration of carbon dioxide in the charge gas is high enough; It becomes impossible to treat the gas of the cargo with 0 desire as a result of clogging the process equipment with solid carbon dioxide (unless carbon dioxide removal equipment is added, which may increase the total cost altogether). This invention prepares a device for producing a liquid reflux stream that will improve the extraction efficiency for the desired product (Led) while at the same time greatly reducing the problem of carbon dioxide icing. and in recent years; The preferred processes for lai hydrocarbon separation use overhead adsorption to give additional refining of the evaporated vapors. The source of the return stream for the upper refining area is preferably a recirculated stream of waste gas that is supplied under pressure. The recycled waste gas stream is usually cooled to extreme condensation by heat exchange with other process streams; For example ; The cold overhead stream coming from the fractional distillation tower. And then the condensate current is greatly expanded from

A

during a masked stretch device; Such as the Yaad valve, the pressure at which the methane removal unit is operated. and while stretching; Part of the liquid will usually evaporate; This results in cooling in the overall stream. Then the fast expanding current is supplied as top charge to the methane removal unit. Typically; The steam portion from the expanding stream 0 and the top steam from the de-methane unit combine in an upper Jad zone in the fractional distillation tower as waste methane gas. as an alternative; The cooled and expanding stream may be supplied to a separating unit for supplying the vapor and liquid streams; So that after that the steam is united with the inertial current from the tower, and the liquid is supplied to the column as an upper charge of the column. Typical ag wall diagrams of this type are shown in US Patent No. 0¢0,AAY,014 5¢0.0TAYFY¢£,AA9,060 in Mowrey, E. Ross “Efficient, High Recovery of Liquids from Natural Gas Utilizing a High Pressure Proceedings of the Eighty-First Annual Convention of the Gas “Absorber” (Processors Association Dallas, Texas; Mar 11-70-0017 Unfortunately, these processes require the use of large amount of compressive energy to give the motive force to return the Ve backflow to the methane removal unit, adding to both the total cost and the operating cost of the facilities using those processes.This invention La uses an overhead refining zone (or column separate refining in some embodiments). This is often done using only available refrigeration in vapor

YY oA

The cold that leaves the upper refining area. And this condensed liquid; which is often liquid methane; It can then be used to absorb the Cp components; components Cy; ingredients,©; And the heavier hydrocarbon components from the rise through the upper refining area, and thus these important components are absorbed in the lower liquid output of the methane removal unit. And below; This lateral retraction feature is used in CPT extractors as described in assigned US Patent No. 7,141,111. Surprisingly, The students found that raising the pressure of the side intake stream in the assignment of US Patent No. 7,191,711 works to improve the extracted quantities of Cat without 0 loss of extracted percentages of Cp and improves the efficiency of the collision; While at the same time it reduces the problem of carbon dioxide icing. According to this invention; It was found that the quantities extracted from © Al Cots more than 99 percent can be obtained without loss in extraction +:© . Z This invention provides another advantage in the ability to maintain an extraction ve greater than 34 percent of the Coty Cy constituents when a day a © constituents are extracted from high to low values. In addition ; Jem This invention is possible to obtain exactly 100% of methane and lighter components of the © components and heavier components while maintaining the same extraction ratios as in the previous field and improving the safety factor 0 in relation to the risk of icing of dioxide carbon carbon dioxide. And this invention; Although applicable at lower pressures and warmer temperatures 0 ye charge in the range from 400 to gases is particularly preferred when treating gases (absolute) or JE ul 0.347 kE to [247] and drawings A BY for a better understanding of this invention ; Refer to the following °. Brief description of the drawings: With reference to the drawings: Belonging to the field natural gas Represents a sequence diagram of a natural gas processing unit 1 of the previous figure according to United States Patent No. 141,517, / 0 Fig. ¥ represents a sequence diagram of a natural gas processing unit according to this invention; Fig. ? represents a carbon dioxide concentration-temperature graph showing the effect of this invention; carbon dioxide flowchart showing an alternative means of using this invention on Jia in the form of Vo; a natural gas stream; in the form of © representing a graph of the concentration of carbon dioxide Carbon dioxide temperature The effect of this invention for special processes is illustrated by Figure 4; Figures 6 to 4 represent sequence diagrams illustrating an alternative means of using this invention on a natural gas stream; and _ 0

11 represents a partial sequence diagram illustrating an alternative means of completing the fractionation of charge 01 of the vapor form according to this invention. The previous detailed description; Tables are prepared summarizing the flow rates that the JES has in the following explanation: "It has been calculated for typical process conditions. In the clear tables here; the denominator of 0 has been rounded. Flow rates (in moles per hour) to the nearest integer for the purpose of convenience. The total current rates shown in the tables include all non-components and are therefore generally greater than the sum of the hydrocarbon current flow rates for the hydrocarbon components.The temperatures indicated are approximate values that have been rounded to the nearest degree. It is also worth noting that Ye process design calculations made for the purpose of process comparison are based on the assumption of no heat leakage from JIS SY) described in

Aad (or to) the atmosphere to (or from) the process. The quality of commercially available materials makes that a very reasonable assumption and is exemplified by those skilled in the art. Vo For the purpose of convenience; Process parameters are listed in each of the conventional units. Systeme International d'Unités (SI), British, and in units for the interpretation of the gram-molecular flow rates mentioned in the tables as either the number of moles per pound per hour or the number of moles per kilogram per hour. Energy consumptions and/or thousands of British thermal units per hour (HP) are given in horsepower 0

VY

which corresponds to the stated gram molecular flow rates in moles in (MBTU/HY) kilograms per hour. The above field description represents a sequence diagram showing the design of a processing unit to extract 1 figure using the above field according to a patent. natural gas from natural gas Cpt Ingredients _ 0

Sal assigned American No. 7,191,117. And in this simulation of the process; Absolute square ag lb/ 0010 and [LE] P 9071 enters the unit at and if the entering gas contains a concentration of . ©1 kPa (absolute)] as a stream,171] of sulfur compounds that may prevent product streams from meeting specification; And is removed. sulfur compounds by appropriate charge gas pretreatment (not shown) Ye and in addition; Water is usually removed from the charge stream to prevent the formation of hydrates (ice) under extreme cooling conditions. Typically a solid desiccant is used for this purpose. Jalal is heated by 01 in the FY heat exchanger and the charge stream is cooled by a dis wo re-unit (TEA [-7””m] (OYA stream with resulting residual gas at 0 liquids) 41 [7”m] (Fo current at methane boiler of the de-methane unit [-77 then] GY em side reboiling (The upper side of the decondensing unit (sale) liquids) 40 (stream is AY unit and the cooled stream enters YS (stream [CY] GVA) at kPa [VN oY] psi 0171 and [OY] P-905 at 11 ch Yo

FY of the condensed liquid (stream (TY (absolute)] as the vapor is separated (stream

\Y

The liquid leaving the separator (for Jedi loam W(PF) stream (77; approx. psi [1,477 kJabs]) from the fractional distillation tower 19 is expanded by expansion valve 1 in cooling system a to COVA [-1””m] before being supplied to turret 19 at the lower cargo hold located at

© mid-column. The vapor (FY stream) from separator unit 11 is split into two streams; FA Yo and stream Fo containing about 777 total vapor; pass through heat exchanger Vo in Ala heat exchange with The residual gas cooled at [PAA] COV YY (stream (AA) is then cooled to primary condensation. The exposed stream 0 is then greatly expanded resulting AH at -71 sf [PAT] rapidly through a valve Expansion 16 J The operating pressure of the fractional distillation tower 48 and during expansion a part of ll is vaporized resulting in the total stream being cooled to - “0F [PAY] and the expanding stream b is supplied to the fractional distillation tower 14 at the top charge position located at

mid-column. yo The remaining part of 77614 steam from the separation unit (FL) 11 enters the expansion machine 117 in which the mechanical energy is extracted from this part of the high-pressure charge. The VY expands steam isothermally to the operating pressure of the turret; With the expansion potential, the expanding current I is cooled to a temperature of approximately Ge [-14 µs]. Typical commercially available Ye expansion agents are capable of extracting 80-788 of the theoretically available voltage in a typical isothermal expansion. Le is used to drive the extracted voltage

(d) a central compressing unit (eg element VA) that can be used to re-compress the residual stream (EA) for example. The partially condensed expanded stream A is then supplied as charge to the fractional distillation tower 16 at a secondary position For the lower charge located in the middle of the shaft.

° The methane removal unit in tower 19 is a conventional distillation column containing several vertically spaced flat pans; one or more layers of packed cot; Or a union part of the flat spheres and the swarms. The tower of the methane removal unit consists of two parts: an upper absorption (refining) part 11a contains flat pans and/or shims to provide the necessary contact between

0 The vapor portion of the expanding streams blow 5 sacl andl IY upwards and the cold liquid descends downward to act on the condensation and absorption of the components (Cp 03” and heavier components; the lower contact (de-methane) zone 11b containing the flat basins and / or gaskets to provide the necessary contact between downward liquids and upwards rising vapors The contact area 401b Lad may include

Ve has reboilers (such as the 01 shige reboiler, reboiler, and static reboiler shown earlier) that heat and vaporize a portion of the liquids flowing down the column to supply the extraction vapors that flow up the column to remove the liquid product; current £Y ; of methane and lighter components. The current enters

“A in a de-methane unit 19 at an intermediate charge position placed in the area

The bottom YL of the absorption part 04 in the methane removal unit 1% and the part mixes

The fluid from the expanding stream with the fluids falling down from absorption region 114 and extending

Yo

A The liquid condensed downwards into the contact area 41b of the methane removal unit A01 The vapor part of the expanding stream ascends upwards through the absorption area “Cy” and is in contact with the cold liquid that descends downward to condense and absorb the constituents © Components ; and heavier components.° part of the distillation vapor (stream 7£) is withdrawn from the upper region of the contact part 4 Sg after which this stream is cooled from 11"-"F [-0m] to -SOV Ys [-0m] and partly condensed (stream (Ter) in the YY heat exchanger by heat exchange with the cold upper stream of the YA de-methane unit exiting from the top of the 19-de-methane unit at -; 10”F [LAY] The cold upper stream of 0 demethanation unit is slightly warmed to -110"F [PAA] (IPA stream) as it cools and condenses at least part of the AY stream and the The operating pressure in the reflux unit (EVA) YY psi [7.981 kPa (absolute)!) at a pressure lower than the operating pressure of the OLE 11 demethane unit provides driving forces causing a stream of 0 vapor to flow distillation through the heat exchanger YY and then into the reflux unit YY where the condensate liquid (stream 80) is separated from the submersible vapor condensate (stream 46). Meshthan 8” from the heat exchanger YY to form the waste gas stream EA at YY- to then [PAA] A and the liquid stream £0 from the reflux unit YY is pumped by the YE pump to Higher pressure Su than the operating pressure of the methane removal unit

L 4 and then the stream 46 is supplied as a cold upper column charge (reflux) — de-methane unit 19. The cold liquid reflux absorbs and condenses the lesser components that Law in the upper refining area of the absorption area 118 of the de-methane unit NA ° In the extraction zone 11b of the methane removal unit 04, the charge streams are extracted from the methane components and their minor components. The liquid product (stream 7;) exits from the bottom of tower 19 at POY [211] based on a typical lial ga of methane to ethane ratio of 0.076:1 on a molecular gram basis in the bottom product. The distillation vapor stream constituting the top_0 stream of the tower (stream YA) is heated by the heat exchanger YY as it provides cooling A the distillation stream EF as previously indicated; then the downstream combines to form the waste gas stream pad 48. The waste gas passes in an opposite current to the incoming charge gas in heat exchanger V0 where it is heated to GOYA [-77] (stream 4;a); and in heat exchanger 01 where it is heated to COV oY [26] (current EA 0) as it provides cooling as previously indicated. The waste gas is then re-compressed in two stages, the piston VA driven by the expansion machine 117 and the piston YY pushed by the After the GEA stream is cooled down to 0" f [2264] in vacuum yal sa ag YA the tail gas product (J) (fA) flows to the gas pipeline at Vo fe psi [VAY] 0 kPa (absolute)]. YYoA

VY

A summary of current flow rates and energy consumption for the process described in is shown in the following table: 1 Figure 1 Table (1) Figure Summary of current flow - moles per pound / hour [kg mol / h ] °

Gall disc ethane. propane butanes + carbon dioxide gd raytla p Vey 7977 vay 0. Yo.YAY 8 mm yyy YY. vv 07 1.74 YY Clap 1 Yo 11 97 Ye 01 79 1.166 91 Ya 117 AG (Yo \V.vo) £19 01 10 VY¢ 1.4 15

Y.A 101 1 8 5 Y.049A ty 0 0 vy 1.7 23 04 m ot 1 ° Ty ye go rahla YY.AQY yy 0 ° 46 7.6 YA Yo.YoA EA qa ° Yo.q00 771 0 ey 81 lah a y. eo 7 YY Extraction ratios *

Ya

LAY. 0 ethane JaA.0. propane 744.9¢ butanes butanes + energy kW] Ye 690] Compress the waste gas 64 forces (depending on incomplete flow rates) * 1 Example illustrating the figure ? Sequence diagram of a process according to this invention. and the composition of a gas > is the same as 1 the charge and conditions taken into account in the process represented in the form and accordingly ; The special operation of the form ¥ can be compared. 1 that in the form of To illustrate the advantages of this invention. ; The inlet gas enters by heat exchange with 01 and is cooled in heat exchanger 1 of the unit as stream 0 (stream *”#b); Reboiler fluids [06] GPT Residual gas produced at (stream 14); Reboiling liquids [24] PEA at methane of the de-methane unit 4); Recycling fluids 0 (current [°V0-] bottom side of the de-methanation unit at -5”V) Fe (current [GPov=] upper side boil of the de-methane unit at - . Lav 0101f [TAS] GOA at 11 ATF separator and cooled stream enters 0 FY (kPa (absolute)] where vapor is separated (stream 7.017 [psi ,

Jail The liquid that has been condensed (stream 7"). The liquid of the Eva unit may be fragmented

The stream (MF) is in some cases divided into two streams » stream 7; and stream FY. In this example of this invention all the liquid exiting from the separator in stream PY is directed into stream PY and is expanded to a pressure 017 psi FLY WA [kPa (absolute)]) from distillation tower 19 by means of a VY expansion valve 1© and cools the stream “?a to PNAS [201] before being supplied—fractionation tower 19 at the bottom charge position located in the middle of the column. In other embodiments of this invention all the liquid of the separator in stream 0" may be directed to stream 49; or it may Part of stream 3 " is directed to stream YY with the remainder to stream AY 01 and the vapor (stream FY) from separator 11 is split into two streams;* and 6. A union may be (FE Lal containing about 777 total vapor; in some embodiments with a portion (stream 47;) of the liquid stream of the separator “© to form the cocurrent Yo and may pass FE all or Yo; as may be Case; through the heat exchanger 15 in a heat exchange relationship with the cold residual gas at Py vom [haltham] 10 (stream) (IMA) where it is cooled for the purpose of intense condensation. The resulting condensed stream Tro at -010°F [PVE] is then rapidly expanded through condensing valve 16 to the operating pressure of the fractional distillation tower 19. During expansion a portion of the OLN is evaporated resulting in total current cooling. In the process shown in Figure oF the expanding current 0b leaving the expansion valve 16 reaches a temperature [PAGS] COV YAS and is supplied 00 to the fractional distillation tower 14 at an upper charge position in the middle of the column.

a

The remaining AVA of SA from separation unit 11 (current (FT) enters the expansion machine 117 in which mechanical energy is extracted from this portion of the high-pressure charge. The VY machine operates Upon expansion of the vapor to the working pressure of the tower and with the expansion voltage the condensed stream is cooled IF ºC up to approximately [GOV Y= LOVES] and the expanded stream partially condensed a is then supplied as a charge to the fractional distillation tower 14 at A second charging location

The bottom one is in the middle of the column. The methane removal unit in Tower 14 is a conventional distillation column containing several vertically spaced flat pans; one or more layers of 0 packed cots; Or a union part of the flat and gaskets. The tower of the methane removal unit consists of two parts: an upper absorption part (refining) 41a containing flat basins and/or gaskets to provide the necessary contact between the steam part of the caro san all and “a” streams rising upwards and the cold liquid descending downward to work on condensation and the absorption of the “Cp” components, “Cy” and the heavier components; and the lower contact 1 (de-methane) zone 11b containing the pans and/or gaskets to provide the necessary contact between the downward liquids and the upwards vapors. The contact zone 1b Lead may include reboilers (such as the configured reboiler 0, reboiler and side reboiler shown earlier) which heat and vaporize a portion of the liquids flowing down the column to supply contact vapors that flow up the column to remove the liquid product; Lal 47; of methane and lighter components. Stream “A” enters the de-methane unit

AR

1 At a medium charge position placed in the lower region of the absorption part V4 and the liquid part of the expanding stream mixes with the liquids that descend VS the methanation unit and the combined liquid extends down into region #1 down from the absorption region The vapor part of the stream rises. 19 methane extraction 11b from the methane removal unit and is brought into contact with the cold liquid 14 expanding upwards through the absorption zone © components .b©; And heavier components. (Cp descends down to condense and absorb the components and part of the distillation vapor (stream ";) is withdrawn from the upper area of part of the IVT [-8 l"m] of the expanding stream GY A= by J contact 1b at compressed to 604 psi [£148 kPa (Abt)] by - to [PN] COVA from EY and this stream is then cooled from 71. Steam press 0 by exchanging YY in the heat exchanger (Te) and partially condensing (the stream [PAV-] Yo) leaving the upper part of the thermal YA with the cold upper stream from the demethane unit The cold upper stream is heated from the [PA] P “1”-1 unit at 19 the methane removal unit as it cools and condenses the IFA (stream [VT] GO) vom the methane slightly to At least part of the current? Methane removal unit

Ol operation of the fractional distillation tower 91. During expansion a small part of the gas is evaporated resulting in cooling in the total stream to -711F [-211C]. And then the supply is done

Nola by the expanding stream 7;c as a cold top (reflux) charge of the column to a removal unit 0 with distillation steam rising from stage 2 £F and the steam part (if present) of the stream is combined

YY oA

YY

While the FA reflux fraction absorbs the upper fractional distillation to form a tail gas stream the cold liquid and condenses the components: © ; ingredients©; and heavier components rising in the upper refining zone from the hydrocarbon zone hydrocarbon 13 methane uptake 119 from the methane removal unit ° Operating pressure is maintained in the YF reflux unit (78; psi [7.901 kPa (absolute)]) at a pressure lower than the operating pressure of the SLE 19 removal unit. This provides driving forces causing the distillation vapor stream 47 to flow through the heat exchanger YY and then into the reflux unit YF where the condensate (stream £0) is separated from the non-vapor Cie cml al that has been warmed se Lal) (current ;;). Contact area 91b of de-methane unit 14 Charge streams are recovered from the methane and its lighter components The liquid product (stream £7) exits from 0 bottom of tower 15 at GOTT [219] and a stream is heated The distillation vapor forming the cold tail gas stream © in the heat exchanger YY as it provides cooling to the distillation stream pressurized TE as previously shown.The tail gas (FA stream) passes in an opposite stream with respect to the charge gas entering the exchanger Thermal Cua 11 is heated to - [Ped] fn (current (FA) and in heat exchanger 01 where it is heated — GOV).© [©;then] (current EA c) Cua It provides cooling as previously indicated.Then the waste gas is re-compressed in two stages; The VA piston driven by a machine

YY

and the piston 77 which is driven by an auxiliary power source. And after 11 expansion is cooled; The product gas YA “f [064] flows into the vacuum refrigeration unit 101 AH 4 to Lal psi residual Vet (stream *”f) to the gas pipeline at kPa (At)] .VAY] A summary of the current flow rates and power consumption of the process shown in Guy ° Fig. ? In the following table: 1 Table (1) Current flow summary figure - lb.moles/hr [kgmol/hr]

Ve Total pd 8 Butanes+. ghd Nathiyala ghd Raytla Carbon 16 Vey 797 yay 01 117 Sun 71/471 VY. Ya. YY. Yo..o. vy ave YY YoY oY lo 7171 YY 0.44¢ \oV Ya TA 7141 Rack One 7077 AT 101 1 and Support Ya

EV) 1 0 ARR ¥.av1 L 1”... (WY 0 Y Yay Yo.YoA YA 0.111 Yeo ARR Yi. 81 Y¢ 31 * extraction ratios

Y¢

JAY. ethane 711.777 propane propane 744.4Y butanes butanes + energy (depending on incomplete flow rates) * that; compared to the previous field; That this invention 1 and 1 shows a comparison of the two tables against 787,056) ¢ but ZAT. +0) basically maintains the same ethane extraction improves both propane extraction (744.37 compared to 98.50 7) and butanes extraction © and 7 also that 1 compared to 94.14 7 (comparing the two tables shows 94.39) butanes + those increased productions were achieved using an electrical statistical power less than a statistical power; or less by 17.474 horsepower compared to 111789 (the previous field 18) more than 1. There are three factors Firstly, the pressure boost provided by the YY steam piston allows the upper column (FA stream) to condense all of the distillation steam stream 7; As a result, the return current Goll (gla) of this invention is © times larger than that of the previous field 0 (current $0 off providing more efficient refining in the upper region of the absorption region party

Yo

1g second; by increasing the amount of upstream return current possible by this invention; The amount of secondary return current ite can be correspondingly reduced without reducing the output yields. This in turn leads to more flow (stream) of the expansion machine (YR) 11 and the resulting increase in energy that is recovered to operate the VA piston and thus the 0 power requirements of the BIEL YY piston are reduced Allows for the most efficient refining it provides Stream Sty the upper region of the absorption zone 194 by operating the methane removal unit 18 at high pressure without reducing the yield; this also reduces the specific capacity requirements

with the AY piston. Another advantage of this invention is the small possibility of carbon dioxide icing. The JSS ¥ is a graph of the relationship between carbon dioxide concentration and temperature. Line VY represents the fifth equilibrium states of solid and liquid carbon dioxide in methane. The liquid-solid balance line in this graph is based on the data shown in Figure 11-3 on page 11-74 of the Engineering Data Book; second edition; published in Vo 0001 by the Gas Processors Suppliers Association (which is often used as a reference when reviewing potential icing conditions). The temperature to the right of line 1 denotes no; or carbon dioxide concentration at or above this line; to a frozen state. and because of variations that ordinarily occur in gas handling means (eg; charge gas composition; conditions; flow rate); It is usually desirable to design a methane removal unit that has a large safety coefficient between the expected operating conditions and the icing conditions. (Experience has shown that the fluid conditions are

‎YYoA

The five stages of fractional distillation of the methane removal unit; Contrary to the conditions of vapors; It typically controls the allowed Jil conditions in most de-methanation units. For this reason ; The vapor-solid equilibrium line corresponding to Fig. 3 is not shown. Also, in the form of “a line was drawn representing the conditions for the liquids in the phases of fractional distillation from the methane removal unit 146 in the fifth process in Figure 1 of the previous field (line VY). As we can see, part of the Jill line shows This is located above the solid-liquid balance line, which indicates that the special process of form 1 of the previous field cannot be operated at those conditions without encountering problems 0 related to carbon dioxide icing and as a result It was not possible to use the special process in form 1 under those conditions, and thus the fifth process in form 1 could not actually achieve the extraction efficiencies mentioned in Table A when performed without removing at least part of the carbon dioxide from the charge gas. This, of course, serves to increase the total cost to a large extent. Line VY is represented in the form of “the conditions for the liquids on the fractional distillation stages of the methane removal unit 14 of this invention as shown in Fig. ”. In Figure 1 of the previous field, there is the lowest safety coefficient of 017 between the concentration of carbon dioxide in the column fluids for the expected operating conditions of the special process in Figure 7 versus the concentrations at equilibrium phase 0 of the solid-liquid material. any ; It would take an increase of 710 percent in the percentage of carbon dioxide in liquids to produce icing. Hence ¢ this invention will bear the concentration of YYoA

And it is 10 percent greater than the concentration of carbon dioxide its charge gas than the special process of form 1 of the previous field that can bear without the risk of conflicting with the solid-liquid balance line. And also; While the process of Fig. 1 of the previous field cannot be operated to achieve the extraction rates mentioned in © Table 1 due to icing; This invention can in fact be operated at extraction levels higher than those listed in Table 1 without the risk of icing. It is possible to understand the change in the operating conditions of the special methane removal unit in the form of? As indicated by the line VY in Figure © by comparing the distinct characteristics of the subject matter of this invention to the previous field process of Figure 1.

01 While the shape of the operating line of the process shown in Figure 1 of the previous field (VY line) is similar to the shape of the operating line of this invention (VF line), there is a major difference. The operating temperatures of the fractional distillation stages are The upper critical level in the de-methanation unit in the special process is warmer than that of the fractional distillation stages in the de-methane unit in Figure 1 of the previous field process;

1 What causes the displacement of the operating line of the form? effectively away from the liquid-solid balance line. The warmer temperatures in the fractional distillation stages in the Y-form de-methane unit are primarily a result of operation at higher pressures than the previous field's Figure 1 process. and in any case; The higher operating pressure of the tower does not cause a loss in the extraction levels of the Cot component due to the distillation steam stream?; In process

© fig. Essentially a direct contact open press-cooling cycle of the demethane unit using a portion of the inner column vapor as the process fluid - supplying cooling to

Ya

The process necessary to overcome the loss in extraction that is naturally associated with an increase in methane. The operating pressure of the methane unit. Another advantage of this invention is a decrease in the amount of dioxide

EY in the liquid product stream 1 leaving the carbon dioxide methanation unit © and by comparing the stream “; in Table 1 of the process of Figure 1 of the previous field with the stream EY in Table ¥ of Figure Y which is an embodiment of this invention we find that there is approximately a reduction of TY in the amount of carbon dioxide which is absorbed into the stream £Y by this invention.This generally results in a reduction of the requirements for processing the output by a corresponding amount;a reduction of both the total cost and the cost of operating the treatment system.1 One of the inherent characteristics of the operation of the demethane column for the extraction of the Cot components is that the column must perform a fractional distillation between the methane leaving the tower as its upper product (vapor stream) (FA) and the components Cot Which leaves the tower in the form of its lower product (SL (liquid 47)) In any case, the volatility of carbon dioxide is between that of methane (Cot Sl Sally 05), which causes the appearance of carbon dioxide in both Also, carbon dioxide and ethane form a constant boiling mixture, which results in methylation of carbon dioxide to the accumulation in the middle fractional distillation stages in the column, thus causing the formation of large concentrations of carbon dioxide in the tower fluids. a The return streams for adsorption region #0a in the methane removal unit 4 of the Fig. 1 process in the previous field are streams 5;a and **b; while

The one of this invention dul in the form of Y represents the two currents ;* faces “b. Comparing those streams in table 1 and table oF, we note that the total quantities of components: © and carbon dioxide in the reflux streams in the process of Figure 1 of the previous Jl sal is 470 PVA lbs. mol/hr [70; and 81 © kg mol/h] ; Respectively ; against POF and 7176 lbs. mol/hr [Yor [YT] kg mol/hr] ; Respectively ; The backflow currents in the fifth process in form 1 are the subject of this invention. Significantly less of the constituents of the adiabatic mixture enter the absorption region ?0a in the cold liquid return streams; and enter instead at the bottom; warmer than absorption zone 19 0 by stream A so that there is less accumulation of carbon dioxide in the fractional distillation stage of absorption zone 09 . This allows more carbon dioxide to escape into the upper FA stream rather than being absorbed into the resulting liquid stream. 4 . Example 1 shows an alternative embodiment of this invention in Figure 4. and the gas composition of the charge and the conditions taken into account in the process being represented in the form of; They are the same as those in Figures 1 and Figures 7. And accordingly; shape can be compared; 1 process of the foregoing art to illustrate the feature of this invention; It can be compared in mass with the embodiment shown in Figure 1.1 and in the simulation of the process in the form of day of gas entering the unit as stream 1 and cooled in heat exchanger 01 by heat exchange with YYoA

Ye.

Cold residue gas at = [P06] CPT (stream (QA sale unit fluids) demethane boiler at 1#"V [VV] (stream 14); reboiling fluids Lower side de-methanation unit at -10V [YY] (40 stream); upper side de-methane reboilers at -715F

m [Pes] (current (FS) and the cooled stream enters ITY 11 separation unit at - OFA q [OFA] and 1710 psi VN Y] kPa ( Absolute)] Cua The vapor (stream (PY) is separated from the condensed liquid (stream (YY) and the liquid of the unit (FY lal) ad may in some cases be partitioned into two streams » stream 49 and stream FY In this example of this invention: Each

0 The liquid leaving the separator in the stream? to the stream PY and is expanded to the working pressure (approximately EAs psi [3.704 kPa [3.704 kPa]) from distillation tower 19 by the expansion valve VY and cools the stream

VA before being fed to the fractional distillation tower [Pee] -177F fy

At the bottom charge position located in the center of the shaft. And in al embodiments of this

VO invention; All liquid of the separator may be directed in the stream “* to 1 with the remaining part directed to 917 or part of the stream ©” may be directed to the stream

AY current

The vapor (stream (FY) from separation unit 11 is fractionated into FAVE COs

and the current may be united ;*; containing about 7277 total vapors; In some 0 embodiments with a part (stream 8) of the liquid stream of the separating unit PY to form the combined current Fo and the stream 6 or Fo may pass as the case may be; through the heat exchanger

‎YYOA

0 in a heat exchange relationship with the residual gas cold at -6 0F [2YV=] (stream (vA) as it is cooled for condensation wa AN and the resultant stream which has been strongly condensed #8 is then dilated At -710"F [PVE] rapidly through an expansion valve 01 to the operating pressure of the fractional distillation tower ve and during denaturation a portion of the stream is evaporated, resulting in cooling of the total stream. In the process shown in Fig. The expanding stream B leaving the expansion valve 111°C - [PAA] CNY reaches and is supplied to the fractional distillation tower VA at an upper charge position in the middle of the column. The residual fraction, in AVY, enters of steam from the separating unit (FOL) 11 0 in the expansion machine 11 in which mechanical energy is extracted from this part of the high pressure vessel. By means of the expansion voltage the IF is cooled to a temperature approximately to -010°F [VES]. The partially exposed IF expansion is then supplied as charge to the fractional distillation tower. 19 at a second bottom charge position located in the center of the shaft. Part of the distillation vapor (stream ";) is withdrawn from the lower area of the absorption zone 118 of the 14 methane removal unit at 117- TV [PAV=] above the expanded al "a and is compressed to 114 psi per square inch absolute [£71 © kPa (absolute)]) by piston 1 ?. The stream compressed We is then cooled from -4-8F [210] to -; [PAV] and greatly intensify the current (EY) in Druv

YY

Heat exchanger YY by heat exchange with the cold upper stream of the de-methanation unit FA exiting from the top of the methane-1 unit at GOYYA-[-2+15m]. The cold upper stream from the methane removal unit is slightly heated to [VY] CY Tm (ITA stream) as it cools and condenses at least part of the stream? The working pressure of the demethanation unit 09 it is rapidly expanded through the expansion valve yo to the operating pressure of the fractional distillation tower 09. During denaturation a small part of the stream is evaporated, resulting in cooling in the total stream to [PO] The IS is then supplied with the expanding stream 9;c as a cold upper charge (reflux) of the column to the unit 0.09 methane removal and the steam portion (if present) from the stream 4c combines with the distillation steam rising from the upper fractional distillation stage to form A stream of tailing gas PA; while the cold liquid reflux part absorbs and condenses the components Cp; components ©; and the heavier hydrocarbon components rising in the upper refining zone from the absorption zone Ve of the methane removal unit 09 . Vo In the extraction area 4 Ab of the methane removal unit 09, charge streams are extracted from the methane components and its lighter components. The liquid product (stream ;) exits from the bottom of tower 15 at [PY] GOV . The distillation vapor stream constituting the cold residue gas stream (stream FA) is heated in the Cua YY heat exchanger and it provides cooling to the compressed residue gas stream FEF as previously shown. The waste gas (stream 8”a) passes into YS Countercurrent with respect to the charge gas entering in heat exchanger V0 where it is heated to - “P [Poo] (current PA) and in heat exchanger 01 where it is heated to YYoA vy . (current 44 c) where It provides cooling as predetermined [OF] ph 0011 to propellant 18 after which the waste gas is re-compressed in two stages; the piston being driven by an auxiliary power source YY and the piston 1 a all by machine “F [495”m] in refrigeration unit 111 and after stream 4 is cooled; e to . to the gas pipeline at 6A the residual gas product flows (vacuum stream YA 0 kPa (absolute). VAY] psi 0 A summary of current flow rates and energy consumption for the process shown in Fig. 01 is shown in the following table: 7 Table (Fig. 01) Summary Current flow - moles per pound/hour [kg mol/hr] Total pdf Butanes . Thani Napurbla BW gd Raytla Carbon > mm mm mm mm 11 7 1

YY. ET) VY. VA. vy. 1..941 Yo..o. YY +7 yy YoY oY vo YY 0

AVY VY ¢ Ve viv 0.1% voy 7». 88 VE Yiu 4m V4.6) ¢ 4 Total wll Butanes. Glad GY ghd Bi-Raytel Carbon * £4 Yo 0 1 and Yeo ¥.41Y for Eve

Yi

Y1..00 £vo Y Yay Yo.yoA YA

Yoo YA M Lm 114 Y¢ ¢Y * Extraction rates

LAY. 1 ethane 744.04 propane propane 744.94 butanes butanes + energy (depending on incomplete flow rates) * ° Explain the comparison of the two tables? The © that; Compared to the embodiment of this invention found in Figure 7; Special anthropomorphism works as; It has to maintain the same extraction of ethane, but improves the extraction of propane (6 vs. 744.73) and butanes + butanes (749.94 vs. 799.17) slightly. And on any Alls; Explain the comparison of gabdoline? And 3 also that those outputs were achieved 0 by using a horsepower about 77 less than that required by the embodiment of the subject matter of this invention in the form of ?. The decrease in the statistical power of the special anthropomorphism is in the form of; Mainly because of the lower proportion of Cot components in the YY oA ro stream upper reflux EY which provides more efficient refining in the upper part of the absorption zone 114 so that the methane removal unit 19 methane can be operated at a higher operating pressure SUB (Thus reducing the requirements of (aia) without reducing product yields. By comparing the distillation steam stream '; The concentrations of the Cp components, especially the Cot components, in the current “; In the current EF 0 of the embodiment of Fig. 4 it is the result of drawing the distillation vapor from the lower part of the absorption region 114 instead of the upper part of the contact region 40b as in the embodiment of Fig. ?.The distillation vapor is at the position of the upper column subjected to greater refining than the lower distillation steam in the column, and is closer to the pure methane stream, which may represent the reflux stream hal from the top of the column. Vo and in the processes of the foregoing field shown in Figure 1; the upper (FA) stream of the column cannot condense a pure methane stream; but with the rise in pressure made by the steam piston YY the subject of this invention; The upper stream of column FA is cold enough to act entirely on the condensation of the distillation steam stream 49 although it is mostly pure methane. carbon dioxide compared to embodiment

YYoA

of Fig. 1. The © graph is another graph of the relationship between carbon dioxide concentration and temperature; Line VY, as previously, represents the equilibrium conditions for solid and liquid carbon dioxide in methane, and line VY represents the conditions for liquids in the fractional distillation stages of Unit 0 of methane removal 19 in the process of the previous field, as in Fig. 1 The line VE in Figure 0 represents the special conditions of the liquids present in the fractional distillation stages of the methane removal unit 14 of this invention as shown in Figure 0 and shows a safety factor of 0.7 between conditions of ds ml expected and icing conditions of the figure; and then; This sputtering, the subject of this invention, also bears an increase of 10 percent of the carbon dioxide concentration without the risk of frosting. Practically 0 can be used to improve the safety coefficient of icing for Bali by operating the methane removal unit at lower pressure (i.e., with cooler temperatures on the fractional distillation stages) to raise component extraction levels +:0 without Facing Ve icing problems. The shape of the line VE is in the form of 0 of the positive anthropomorphism in the form of ; Very similar to that of the YY font in the form of ? For the rendering shown in Fig. 1 . The main difference is the significantly lower concentrations of CO2 from the liquids on the fractional distillation stages at the bottom of the special de-methanation unit; As a result of the drawing of the distillation vapor stream at a position YL higher on the column in this embodiment. As can be seen by comparing the current"; in Tables FY even with the absorption of a smaller amount of dioxide

0 carbon in the charge gas with the lower liquid yield in the embodiment of the subject of the present invention in the form of; ; which generally means that less processing of the product will be required compared to the embodiment of this particular invention in the form of .1 other embodiments according to this invention; In general, it is important to design the adsorption (refining) area in the methane removal unit so that it contains several theoretical separation stages. And on Ala A; The benefits of this invention can be realized as if Ala yo were a single theory; It is believed that even the equivalent of a theoretical fractional distillation phase may allow for the realization of these benefits. Actual Sybil, for example; All or part of the highly condensed distillation stream 0 expanded gE can be combined from the expansion valve Yo ; All or part of the highly condensed stream expanding 68b from expansion valve 0 and all or part of the expanding stream “a” from the expansion machine VY (eg in the pipes connecting the expansion valve to the methane unit and mixed das and will mix Vapors and liquids together Jai according to the relative volatilities of the different components of the total combined streams Ve. This admixture of the three streams will be taken into account for the purposes of this invention as the formation of the absorption zone. In some cases it may be preferable to partition the highly condensed distillation stream "cb". to at least two currents as shown in Figures + to 4. This allows part (current (0) to be supplied above the position where the steam distillation current £F is drawn (and possibly also above the charging position of the expanding current Lo ( Ir is down in the absorption region of fractional distillation tower 15 (Fig. 6 SVs YY oA

Ya

down over absorption column 119 (Figs A and 1); To increase the liquid flow in that part of the distillation system and improve stream refining 4. in those cases; Expansion valve 17 is used to expand current 81 to the shaft operating pressure (forming the current (fo); while the expansion valve yo is used to operate the residual aad (current +0) © to the shaft operating pressure so that the resulting current 0a can then be supplied to the upper part of the adsorption region of the desorption unit 11 (Figs 1 and 7) or to the upper part of the adsorption column 11 (Figs A 35) Figures + and 9 describe a fractional distillation tower installed in pile yp the absorption (refining) column V4 (contact and separate medium) and contact column 14 (distillation column) 0. In Figure A the upper vapor fractionation ( The stream 47) from the contact column 94 is divided into two parts. One of the two parts (the stream ";) is directed to the piston YY and then to the heat exchanger YY to produce reflux to the absorption column 19 as previously shown. The remaining part (the stream £ 4) to the lower region of the absorption column 11 to come into contact with the expanding highly condensed stream Hb and the highly condensed distillation stream scaling 1 (ie of current 0a; or currents 0a and 81a). A pump is used Fo to direct liquids (SF) from the bottom of the absorption column 19 to the top of the extraction column 4 so that the two towers function efficiently as one distillation apparatus. and in Fig. 4 » all the upper vapor (stream 7;) flows to the lower region of the absorption column VA and the distillation vapor stream is withdrawn*; from a higher position in absorption column 14; Top charge position lal 0 expansion FY The decision will depend on whether the fractional distillation tower is

YYOA

Its installation as a single vessel (for example, a methane removal unit 01 methane in figures (Vs 1 cf oY) or several vessels depends on a number of factors Jie size of the unit; distance to the means of manufacture. Conditions of charge gas may indicate unit size; equipment. Abil or other factors indicate that the removal of the VY expansion device or its replacement with an alternative expansion device (eg an expansion © valve) is feasible. For example, the conditions could be any allowable expansion of the condensed portion of the charge current (current (Ire) and/or a fully condensed current (current; 7b). The distillation stream £7 is completely condensed and the resulting condensation 0 is used to absorb the important components (Cp components (Cy) and JY components from the vapors rising through the upper part of the absorption area NA from the 14 methane demerger unit (Figures ef oY 1 nor) or absorption column 14 (Figures A 3). In any case, this invention is not limited to this embodiment. It may be preferable, for example; 1 Treat only part of such vapors in this manner or use only part of the condensate as adsorption agent; In CL al in which design considerations indicate that ol al of the vapors or condensate must pass laterally through the absorption zone 410a of the methane removal unit 14 (Figs. (VT ef OY) or absorption column 19 (Figs + and f) Some cases may prefer condensation Jia instead of total condensation 0 stream distillation Her heat exchanger YY and al cases may prefer the distillation stream $F to be side draft JIS of vapors from a gypsum distillation column 01 YY 0A

$e le instead of a partial lateral induction of vapors. It is also noteworthy; Depending on sl hey the composition of the charge gas stream; It may be preferable to use external cooling

XY part of the cooling of the distillation stream A in the heat exchanger and under some conditions; It may be preferable to preheat the distillation stream?4 before and one. YY to be compressed; As this may reduce the total cost of the press 0, the means to accomplish this is to use the compressed distillation stream 9;a (which is warmer due to the heat of the press) to supply this heating using a four-branched heat exchanger. And in, by, a few of those cases; It may be possible to complete the cooling of the pressurized distillation stream thus reducing the cooling that og al must use air cooling or a means and YA should be estimated by the upper stream YY used in the heat exchanger 0 total and a means cooling for each application and that 71 potential reduction in the overall cost of the press to determine whether or not such embodiment is preferred. According to this invention; The vapor charge may be fragmented in several ways. And in some embodiments; Vapor may be fractionated in a separation unit. in Special Operations and to 4; Vapor fractionation occurs after cooling. and perhaps after separating any oY in the forms 1 stress ; in any case; Before Me Liquids may be created. The gas may be fractionated and each of the streams may be charged 01. Any cooling of the inlet gas as shown in fig. methane to the distillation column (such as demethane unit 01 in fig. fry, care to Contactor 1 “and re currents (VTE oY in form 0 boiling sale) and separator and current “a may be charged to the distillation column (eg unit 0

All and call pole 74; Respectively ; in Figures + and 1). 4. It may be done

YYoA

1 or complete with additional streams 01 in Fig. 01 cooling of stream 6” in the heat exchanger and 1 to 4) and/or cooling ef OY in Fig. 1 and 50 FR of the process (eg external streams When the inlet gas is weak, the separation unit may not be needed, and depending on the amount of hydrocarbons Ve in Figures 4 and 6 to 11 oo is heavier in charge gas and charge gas pressure; d the charge stream does not contain hydrocarbons 4; and 6 to 4 or stream 1 in Fig. 01 'a leaving heat exchanger 1 coolant on any liquid (due to 01 in Fig. 01 cooler 'a leaving heat exchanger of its dew point; or because it is higher than ef that it is at the degree shown in chapter 11 sa add als; thus there are no (cricondenbar 0 .01 Figs. a; and to > Tal JY at (PY lal) pressure Je and the liquid to 9 may not need to be expanded and shipped to the mid-column charge position on the distillation column. or part thereof (current

CoS (Pall) with part of the separator vapor (£Y in dashed line Jad 0) and any .Ve flowing into the combined Pe lal heat exchanger may be expanded through a collimator expansion device (FV) A remaining part of the fluid (the current represented by the dotted line to form the current “A” which is then drained to VY as the expansion valve nor) or let oF (Fig. 14 column ie the position of the charge located at Figures rr and current may be used. (G5 A) (Figures YA) Extraction column 0

Lad Ve and to oF and to 4 and/or current © in the shapes ef »"

To cool the inlet gas or other heat exchange service before or after the expansion step prior to flow into a methane removal unit .methane and according to the present invention; External cooling may be used to supplement available cooling to the inlet gas and/or distillation stream from other process streams; In particular 0 in dls is a rich gas within . The use and distribution of separation fluids and bypass fluids of the process heat exchange methane removal unit must be evaluated and the heat exchanger arrangement for inlet gas cooling must be evaluated for each particular use. In addition to selecting process streams for special heat exchange services.

1 It will also be realized that the relative amount of Dina present in each branch of the vapor charge and) will depend on several factors; including gas pressure; charge gas mount; the amount of heat that can be extracted from the charge; The amount of horsepower available. More charge to the top of the shaft may increase extraction while decreasing the energy extracted from the expansion envy, thus increasing the demand for

0 Statistical power of recompression. An increased Aaa Sl in the shaft will reduce horsepower but may also reduce output extraction. The relative positions of the charges in the middle of the column may vary depending on the composition at the inlet or other factors such as desired extraction levels and the amount of liquid formed during cooling of the inlet gas. Furthermore ; Two or more unions may occur

cd lav charge; or parts thereof; Depending on dal temperatures and quantities

individual streams; The DC is then charged to the charge position located in the middle of the column. This invention prepares an optimized extraction of the constituents, Cy and heavier hydrocarbon components, per amount of useful consumption ©_necessary to operate the process. An improvement in the useful consumption required to run the methane process may manifest itself in the form of lower requirements for la ala all or recompression; lower power requirements for external cooling - lower power requirements for tower reboilers; or union thereof. and while it may be shown there that the preferred embodiments are believed to be the subject of the invention; Those skilled in the art will realize that other and additional modifications may be made in the invention; For Ji, for example; To modify the invention according to different circumstances; types of scarcity; OR OTHER REQUIREMENTS WITHOUT DELIVERING IN THE SPIRIT OF THIS Affiliate_Sponsor as defined by the following claims. YY oA

Claims (1)

daa) elements 1-1 in a process for separation of a gas stream containing “_ methane 0060806; ©( ? carbon atoms) b components and hydrocarbon components; Less heavier hydrocarbon components to volatile residue gas fraction and relatively less volatile fraction 1 containing predominant part ge components CG ¢ © components « and '_ hydrocarbon components' the heavier hydrocarbon components or constituents© mentioned + and the heavier hydrocarbon components; and in that process a) said gaseous stream is cooled through pressure to provide a cooled stream ya; 0 ap) the cooled stream The aforementioned is expanded to a lower pressure and thus further cooled; 011 and OY c) The aforementioned additionally cooled stream is directed to the distillation column 0 and mowed at the aforementioned lower pressure, thus the components are extracted for the lower 04 product Relatively volatilizing; improvements since it is later for cooling; the aforementioned cooled stream Ve is divided into a first stream and a second stream; and (1) Vi the aforementioned first stream cools down to actually condense all the aforementioned cooled stream Vy And later expands it to a lower pressure and thus cools further; Lad (Y) YA after the first Jal rounded elongated coolant is supplied in the feed position in the middle of the column to the distillation column. Y. user; YY oA (Y) 71 The second stream used is diluted to the lower pressure used and supplied in the vy distillation column used at the feed position in the middle of the second column YY; Ye 8 The vapor distillation stream is drawn from an area in the distillation column Yo below the second stream of the used column and compressed to a higher pressure A; vv (©) the mentioned compressed vapor distillation stream cooled by about YA sufficient to condensate at least part of it ¢ and thus form a condensed stream «<a ¢ Ya ) at least part of the condensed stream The aforementioned condensed stream is extended to the lower pressure 7 used and later supplied to the distillation column used in 91 upper feed positions; (V) YY the overhead vapor stream is drawn from an upper area in YY the distillation column used and directed in a heat exchange proportional to vi the piston distillation column used and heated; Thus, ro is provided for at least part of the cooling in the © step; and later the evacuation of at least 71 parts of the heated overhead vapor stream with the used gaseous product as the remaining volatile used; and (A) YA the quantities and temperatures in the feed streams used to the distillation column va used are effective for maintaining the upper 2 temperature in the distillation column va used at a temperature such that 2 the majority of the components in The relatively least volatile product used, £Y, is extracted. YYOA £1 gas of claim 0) being pre-cooled; The used Aled YO gas is divided into a first stream and a second stream; The aforementioned second stream is cooled and later the user distillation column is expanded to the lowest pressure used and supplied to the distillation column F the second column; SA vapor distillation stream© used below second elongated refrigerant stream used and compressed into distillation column 1" higher pressure 1#- process according to claim 1; before the denounced division; The used cooled gas stream is partially condensed; the partially condensed gas stream is separated, thus, in order to provide a vapor stream and at least one liquid stream; the steam stream. The vapor stream mentioned hereafter is divided into a first stream and a second 0 stream; and at least a portion of at least one liquid stream is expanded to 7 lower pressures and supplied to the distillation column used in feed position VY Middle of the third column 1 4- The process according to Claim No. ?, where the first stream used is combined with a part of “at least one liquid stream at least to form a combined stream”. And the aforementioned combined stream gall is cooled in order to ; . It condenses virtually all of the current Js Sad and later expands to the lower pressure and thus cools © further; Later, the elongated combined stream is supplied at feed position 1 in the middle of the first column to the used distillation column; ‎YYoA v and any remaining portion in the liquid stream at least one is extended to A (pressure JAY) and supplied to the distillation column used at 9 feed position in the middle of the third column used. 1 #- Process according to Clause 7; Whereas, the partially used second stream (GS) and the partially denatured second stream are separated thus to provide at least one vapor stream and one liquid stream Y; The steam stream used expands to the lower pressure used; It is provided for the distillation column used in the feed position in the middle of the second column; And at least part of at least one liquid stream that is expanded to pressure 4 at least padi wal and supplied to the distillation column in feed position VY in the middle of the third column. 1-1 in a process to separate a gaseous stream containing methane “C components;” (includes ? carbon atom) Jad components (Cy) ¥ carbon atoms) and heavier hydrocarbon ¥ components components to volatile residual gas; and a relatively less volatile product containing a majority of the © components; CG components; © « and the heavier hydrocarbon components 0 1 of the said © components and the heavier hydrocarbon components hydrocarbon components ¢ VY and in that process (i A) the aforementioned gaseous stream is cooled through pressure to provide a cooled stream ¢ (oo 8) the rounded cooled stream is expanded to a lower pressure and thus further cooled; Ye. and YY oA £A additionally the decomposed is directed to the cooled stream distillation column (z 11) and distilled at the aforementioned lower pressure, thus extracting the components distillation column VY for the relatively less volatile product; 0" mentioned is divided into the cooled stream The refrigerated stream 0 for cooling GY improvements as it is 04 first stream and second stream; and 0 said first stream cools to condensate virtually all said first stream and extends it *1*0 thereafter to the lowest pressure used and Thereby it is further cooled; 1 After the mentioned elongated first cooled stream is supplied in Led *Y* YA in the middle of the column to the contact device feed position 4 and a lower liquid stream feed position and fas_l that produces an upper vapor stream Ye (bottom) where bottom liquid stream 9 distillation column is fed into bottom liquid stream YY used; * 7 first lower feed position Contacting and separating Yo feed position drawn from the upper region into the vapor distillation stream *;* 1 first distillation stream used to form a distillation column Distillation column Yv at least; YA user is compressed to a higher pressure; distillation stream *e* distillation stream va The first mentioned press cools down by about distillation stream *+* 7: condenser stream Jy is sufficient to condensate at least part of it + thus 1 ¢ condensed stream vy YY oA *1* YY At least part of said condensed stream is extended to the lower pressure used and thereafter supplied to the contactor and separator at the upper feed position vo; AR 794 Any residual portion of the vapor distillation stream used to direct the contact and separator used to a second YA lower feed position; Ya *?* The overhead vapor stream used is directed in heat exchange 2 proportional to the first pressurized distillation stream used 3 and heated; thus aiding at least part of the cooling_ in stage 3 (step) 1 ; And later, the discharge of at least part of the heated overhead vapor stream used as a residual gaseous product, a used volatile; 1 and *0*to quantities and temperatures in the feed streams used 52 to the contacting and separating device used are effective to maintain the upper temperature ev in the contacting and separating device used at a temperature of 2 so that the majority parts are extracted Of the components in the relatively less volatile product 4 used. 1 "- The process according to Clause 6, where before cooling, the gas used Divided into a first stream and a second stream; The second denatured stream is cooled and later expanded to the lower pressure Y used and supplied to the contacting and separating device used in the feed position. (slaw position ¢ first. YY0A —A 1 Process according to claim 1; Cus that the used refrigerant gas stream is BS partially; The aforementioned partially condensed gaseous stream is separated thus to provide at least 7 vapor streams and at least one liquid stream; The vapor stream, mentioned later, is divided into a first stream and a second stream; And at least a part of at least one liquid stream expands to the lower pressure 1 used and is supplied to the distillation column used in a feed position in the middle of the column. 1 4- Process pursuant to claim No. 8; Whereas, the first stream used merges with at least part of at least one liquid stream to form a combined stream 1 - and the said combined stream cools down to condense; -- Virtually all of the aforementioned current and later it is extended to the lower pressure and thus additionally cooled; Lad After the cooled elongated combined stream is supplied at 1 feed position in the center of the column to the contacting and separating device used; Any remaining part v of at least one liquid stream is diluted to the lower pressure A and supplied to the distillation column used at feed position 1 in the center of the used column. -01-1 Process according to Clause 7 0 whereby the second used stream is cooled under 1 "pressure enough to be partially condensed; and the partially condensed second stream is separated" thus to provide a vapor stream and one liquid stream stream at least; ; The vapor stream used is expanded to the lower pressure used and supplied ‎YroA o) © for contacting and separating device used in the first lower feed position X used; At least one liquid stream is extended for the lower pressure VY used and supplied to the distillation column in the feed position. A is the center of the column. 11-1 The process is in accordance with the protection element No. +, whereby the aforementioned additional “cooled stream” is directed into the distillation column used and is divided into 7 the lowest pressure used, and thus the components in the relatively less volatile product used are extracted and The first overhead vapor stream produces; the first overhead vapor stream 0 used elongated coolant Lad after is supplied in the feed position in the middle of the column 0 used to the contacting and separating device used which produces a second overhead vapor stream V And a bottom liquid stream 0 is used, where A pada bottom liquid stream is supplied in the distillation column used; the vapor distillation stream oe 0 is withdrawn An area in the contacting and separating device used above the second elongated stream used 1 and compressed to a higher pressure; the distillation stream steam distillation stream “squeeze”_ compressed 1 used cools sufficiently to condense die ea at least; thus forming the stream CES condensed stream 10 user; The first overhead vapor stream 0 used is directed to the contactor and separator used in a feed position 0 second used; The second overhead stream used is directed in a thermal Jal relationship with the vapor distillation stream used and heated; Thus, to provide at least part of the cooling in step (1); YY OA oY YA after discharging at least part of the second heated overhead vapor stream 0 used as residual gaseous product used pilot . gas; Whereas, before cooling; The process gas 011 according to claim No. 11-1 used is divided into first stream and second stream; The second stream used is cooled and later expanded to the lower pressure used and supplied to the contactor and separator in a vapor distillation stream below the first user; and the steam distillation stream feed position; the user is drawn from an area in the contactor and separator above The second refrigerant elongated stream 0 used and compressed to a higher pressure 7 -1” 1 process according to Clause 11, where before the division; the gaseous stream “_ used refrigerant condenses Lia; The aforementioned gaseous stream (all gases) is separated so that Bm YF has a vapor stream and at least one liquid stream; the current ; Al-Bukhari’s vapor stream, which is used later, is divided into a first stream and a second stream. And the stream 0 at least one liquid stream used is expanded to the lower pressure user 1 and supplied to the distillation column used in feed position 1 in the middle of the column. -14 1 Process pursuant to Claim 17; Whereas, the first stream used is combined with at least part of at least one liquid stream in the form of a combined stream 7; And the aforementioned combined stream cools you ; . Virtually all of it condenses (Ley) after being expanded to a lower pressure (pain dl) and thus further cooled; YYoA oy oo The elongated combined stream 3 mentioned hereinafter is supplied at 1 feed position in the middle of the shaft towards the contactor and separator VY which produces a second upper vapor stream and a lower liquid stream oA where said lower liquid stream is supplied to the distillation column 4 used ¢ and any part (Ae) of at least one used liquid stream 0 is diluted to the lower used pressure and supplied in column 1 Distillation column used in the feed position in the middle of the 10 column. CE; Whereas, the second stream used 07 of the process according to protection No. V0 = 1, the partially compressed second stream, which is denied, is separated, thus, in order to provide a Lise stream, “at least one; the vapor stream, a liquid stream, a vapor and a liquid stream” mentioned above. For the lowest pressure used and supplied to the vapor contact device; deposited: bottom first user feed position and separation used in feed position 0 user J laa all at least one extends liquid stream and feed position liquid stream used in distillation column and supplied in Distillation column 1" center column. A -11-1 Improvements pursuant to claim No. 1; © or; Whereas, the vapor distillation stream ¥ used is drawn from an area in the distillation column ¥ used above the second elongated stream used Lady after pressing for pressure; the above . ot -17 1 Improvements according to Claim No. 7 6 whereby the vapor distillation stream Y used is drawn from the distillation column used “over the second elongated cooler stream used and later compressed to the higher pressure. -18-1 Improvements Ly to claim no. © ; As the vapor distillation stream Y used is drawn from an area in the distillation column ¥ used above the elongated vapor stream used and later; Presses for higher pressure. -11-1 Improvements pursuant to Claim 1 1 or; whereas (1) The capacitor current used is at least divided into a first part and a second part; (1) “The first portion used is expanded to lower pressure padi dl and later supplied in the distillation column used in the upper feed position used; and © (©) The second part used is expanded to the lower pressure used and later supplied in the distillation column 1 used in the feed position and the middle of the column above the second extended stream used. 1-1 Improvements pursuant to Claim 7; whereas (1) “The condensed stream used is at least divided into a first part and a second part; (Y)” The first part used is expanded to the lower pressure used Lady after being supplied in a column; distillation column used in the feed position position upper used; © and YYOA oo (YF) The second part used is expanded to the lower pressure used and later supplied in the v distillation column used in the feed position in the middle of the column above A the second elongated coolant stream used. -71-1 Improvements pursuant to claim 0; whereas (1) “The capacitor current used is at least divided into a first part and a second part; (1) “The first portion used is expanded to the lower pressure used and later supplied in the distillation column ¢ used in the upper feed position used; and © (©) The second part used is expanded to the lower pressure used and later supplied in the distillation column used in the feed position in the middle of the column above the expanded steam oly used. 1 7 ?- Improvements pursuant to Claim 6 © 4 or 9 Whereas (1) “The capacitor current used is at least divided into a first part and a second part; “(”) the first part used to expand to the lower pressure used Lady after feeding into a column; distillation column used in upper feed position used; © w 1 (*) The second part used is expanded to the lower pressure used (Lady) after being supplied in column 1 distillation column used in the feed position in the middle of the column above A the second extended stream used . YY The improvements according to Clause 1 whereby (1) Y the capacitor current used is at least divided into a first part and a second part; YY0A (Y) “The first part used is stretched to the lower pressure used and later fed into a device; contact and disconnect used in upper feed position used; And (x) 0 the second part used is stretched to the lower pressure used and later supplied in the contacting and separating device used in the feed position in the middle of the column above the second stretched cooler stream used. 1;7- Improvements pursuant to Claim No. 01; Whereas (1) the “condensed stream ESA” current used is divided at least into a first part and a So part; (1) the first part used is expanded to the least sustained pressure and later supplied in the Upper feed position used; 1 and Y (©) second part used extend to lower pressure used and later supplied in A contacting and separating device used in feed position center shaft over vapor stream 9 The used condensed stream ©*7- Improvements according to Clause VE 17 NY +11 or 11 where (1) “The condensed stream used is divided at least into a first part and a part second y- (Y) the first part used is extended to the lower pressure used and later provided in © the contacting and separating device used in the upper feed position used; 1 and YY oA ov The second part used is diluted to the lower pressure used and later supplied to the OY (©) device in the center of the column above the contacting and separating area used in feed position A. The vapor distillation stream is used where a vapor distillation stream is withdrawn Steam distillation stream 8 as 11 improvements in accordance with Claim No. 71-1 “The user is divided into at least a first part and a condensed stream (1) a second part The first part used is expanded for pressure Least used and later supplied in column (1); upper used feed position used in distillation column oe and 1 after fed in distillation column Lady lower used Toa all The second part used extends (*) VY the center of the column above the feed position used in distillation column A. The vapor distillation stream is used where the steam distillation stream 8 is drawn as 18 Or, 117 improvements according to Claim No. YY) the user is divided into at least a first part and a second part condensed stream (1) after supplying in the Lady column the first part used is expanded to the lower pressure used ( Y) " upper user; the feed position used in the distillation column feed position; Distillation The second part used is expanded to the lower pressure used and later supplied in a column (©) © feed position used in the distillation column 3. The vapor distillation stream is used over the area where it is Steam distillation draft Y