WO2013082242A1 - Offshore gas separation process - Google Patents

Offshore gas separation process Download PDF

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Publication number
WO2013082242A1
WO2013082242A1 PCT/US2012/066986 US2012066986W WO2013082242A1 WO 2013082242 A1 WO2013082242 A1 WO 2013082242A1 US 2012066986 W US2012066986 W US 2012066986W WO 2013082242 A1 WO2013082242 A1 WO 2013082242A1
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Prior art keywords
gas
fluid production
production installation
petroleum fluid
acidic
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PCT/US2012/066986
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French (fr)
Inventor
Michel Daage
Richard A. Davi
Robert B. Fedich
Thomas F. PARKERTON
Michael Siskin
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Exxonmobil Research And Engineering Company
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Priority to US61/566,216 priority
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Publication of WO2013082242A1 publication Critical patent/WO2013082242A1/en

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    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10LFUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L3/00Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
    • C10L3/06Natural gas; Synthetic natural gas obtained by processes not covered by C10G, C10K3/02 or C10K3/04
    • C10L3/10Working-up natural gas or synthetic natural gas
    • C10L3/101Removal of contaminants
    • C10L3/102Removal of contaminants of acid contaminants
    • C10L3/103Sulfur containing contaminants
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1456Removing acid components
    • B01D53/1468Removing hydrogen sulfide
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1493Selection of liquid materials for use as absorbents
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2252/00Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20Organic absorbents
    • B01D2252/202Alcohols or their derivatives
    • B01D2252/2023Glycols, diols or their derivatives
    • B01D2252/2025Ethers or esters of alkylene glycols, e.g. ethylene or propylene carbonate
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2252/00Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20Organic absorbents
    • B01D2252/204Amines
    • B01D2252/20405Monoamines
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2252/00Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20Organic absorbents
    • B01D2252/204Amines
    • B01D2252/2041Diamines
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2252/00Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20Organic absorbents
    • B01D2252/204Amines
    • B01D2252/20426Secondary amines
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2252/00Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/20Organic absorbents
    • B01D2252/204Amines
    • B01D2252/20478Alkanolamines
    • B01D2252/20484Alkanolamines with one hydroxyl group
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2252/00Absorbents, i.e. solvents and liquid materials for gas absorption
    • B01D2252/50Combinations of absorbents
    • B01D2252/502Combinations of absorbents having two or more functionalities in the same molecule other than alkanolamine
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2256/00Main component in the product gas stream after treatment
    • B01D2256/24Hydrocarbons
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/30Sulfur compounds
    • B01D2257/304Hydrogen sulfide
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/50Carbon oxides
    • B01D2257/504Carbon dioxide
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/45Gas separation or purification devices adapted for specific applications
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/14Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by absorption
    • B01D53/1456Removing acid components
    • B01D53/1462Removing mixtures of hydrogen sulfide and carbon dioxide

Abstract

A process for the selective absorption of normally gaseous acid components from hydrocarbon gas mixtures containing both the acidic components and gaseous non-acidic components which is carried out in a gas separation unit located at an offshore marine production installation. The sorbent used in the process comprises a severely sterically hindered amino ether. The process is capable of selectively removing H2S from gas mixtures which also contain C02 in addition to the hydrocarbon components.

Description

Offshore Gas Separation Process

Field of the Invention

[0001] This invention relates to a process carried out on an offshore petroleum production platform for removing acid gases from gas produced at the platform. It also relates to the gas treatment unit for carrying out the process.

Background of the Invention

[0002] As reserves in onshore natural gas and petroleum fields have decreased over time, production of these resources has moved progressively offshore and recently into ever deeper waters. Interest in natural gas production has increased as the utility of this energy source in transport, electrical power generation and other applications have increased in recent years with recognition of the importance of reducing atmospheric carbon emissions. The natural gas produced with petroleum liquids and the gas from a gas field frequently contains carbon dioxide and sulfur in the form of hydrogen sulfide, as well as other acid gases such as, CS2, HCN, COS and sulfur derivatives of light hydrocarbons (mercaptans etc). Hydrogen sulfide (H2S) is desirably separated to meet pipeline specifications before the gas is sent ashore by underwater pipeline in view of its corrosive action on pipeline steels. Similarly, it is also desirable to remove the hydrogen sulfide from gas which is stored or processed at a production facility which is not linked to the shore by a pipeline. When H2S is dissolved in water, it forms a weak acid which promotes pipeline corrosion The most common types of corrosion where H2S is present consist of pitting, blistering, embrittlement, fatigue, and cracking. The severity of the corrosion due to H2S is determined by factors such as oxygen and carbon dioxide (CO2) levels, temperature, gas velocity, pH levels less than 6.5 (acidic), especially in he presence of salt water (conductive electrolyte), internal/external stresses, concentration (parts per million or partial pressure levels). The combination of CO2 and H2S is more corrosive than H2S alone, and can be considered very corrosive when combined with even minute quantities of oxygen and for this reason, removal of both CO2 and H2S is considered desirable.

[0003] The removal of acid gases from the produced fluids on offshore platforms and production rigs raises significant problems. The main constraints for application on an offshore platform are space and weight limitations. Installing a complex system with numerous equipment and extensive utilities to support its operation is against the trend in the offshore industry to pursue compact facilities and to reduce manning levels for safety and logistic reasons and operating costs. A number of different technologies are available for consideration including, for example, chemical absorption (amine), physical absorption, cryogenic distillation (Ryan Holmes process), and membrane system separation. Of these, amine separation is a highly developed technology with a number of competing processes in hand using various amine sorbents such as monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), diisopropylamine (DIPA), diglycolamine (DGA), 2- amino-2-methyl-1 -propanol (AMP) and piperazine (PZ). Of these, MEA, DEA, and MDEA are the ones most commonly used. The amine purification process usually contacts the gas mixture in the form of an aqueous solution of the amine in an absorber tower with the aqueous amine solution contacting the acidic fluid countercurrently. The liquid amine stream is then regenerated by desorption of the sorbed gases in a separate tower with the regenerated amine and the desorbed gases leaving the tower as separate streams. The various gas purification processes which are available are described, for example, in Gas Purification, Fifth Ed., Kohl and Neilsen, Gulf Publishing Company, 1997, ISBN-13: 978-0- 88415-220-0.

[0004] The treatment of acid gas mixtures containing CO2 and H2S with amine solutions typically results in the simultaneous removal of substantial amounts of both the CO2 and H2S. It is often desirable, however, to treat acid gas mixtures containing both CO2 and H2S so as to remove the H2S selectively from the mixture, thereby minimizing removal of the CO2. Selective removal of H2S results in a relatively high H2S/CO2 ratio in the separated acid gas which simplifies the conversion of H2S to elemental sulfur, e.g., using the Claus process. Although primary and secondary amines such as MEA, DEA, DPA, and DGA absorb both H2S and CO2 gas, they have not proven especially satisfactory for preferential absorption of H2S. In aqueous solution, the amines undergo reaction with CO2 to form carbamates. The tertiary amine, MDEA, has a high degree of selectivity toward H2S absorption over CO2 but the commercial usefulness of MDEA is limited because of its restricted capacity.

[0005] An improvement in the basic amine process involves the use of sterically hindered amines. U.S. Patent No. 4,1 12,052 describes the use of hindered amines for nearly complete removal of acid gases such as CO2 and H2S. U.S. Patents Nos. 4,405,581 ; 4,405,583; 4,405,585 and 4,471 ,138 disclose the use of severely sterically hindered amine compounds for the selective removal of H2S in the presence of CO2. Compared to aqueous MDEA, severely sterically hindered amines lead to much higher selectivity at high H2S loadings. Amines described in these patents include BTEE (bis(tertiary-butylamino)-ethoxy- ethane synthesized from tertiary-butylamine and bis-(2-chloroethoxy)-ethane as well as EEETB (ethoxyethoxyethanol-tertiary-butylamine) synthesized from tertiary-butylamine and chloroethoxyethoxyethanol). U.S. 4,894, 178 indicates that a mixture of BTEE and EEETB is particularly effective for the selective separation of H2S from CO2. U.S. 2010/0037775 describes the preparation of alkoxy-substituted etheramines as selective sorbents for separating H2S from CO2. US 2009/0308248 describes a different class of absorbents which are selective for H2S removal in the presence of CO2, the hindered amino alkyl sulfonate, sulfate and phosphonate salts, with the sulfonate and phosphonates being the preferred species.

[0006] Regardless of the improved selectivities and sorption capacities offered by those new materials, they have not achieved general acceptance for use in offshore units, the reason being that as regulations regarding toxicity and biodegradability of chemicals that could potentially be spilled into the ocean have become more severe, the potential number of acceptable absorbents has become correspondingly more limited. Acid gas clean-up on off-shore platforms has therefore come to require absorbents to be selected for with lower toxicity and higher biodegradability.

Summary of the Invention

[0007] We have now identified a class of absorbents which have high selectivity for the removal of H2S in the presence of CO2 with very acceptable environmental properties permitting their use in offshore installations such as natural gas production platforms.

According to the present invention, therefore, we provide a process for the selective absorption of normally gaseous acid components from gas mixtures containing both the acidic component and gaseous non-acidic components, which process is carried out in a gas separation unit located at an offshore marine installation. The preferred asorbents used in the process comprise severely sterically hindered amino ethers, including ether alcohols, bis-(amino) ethers and alkoxy amino ethers; mixtures of the amino ether compounds may be used. The process is capable of selectively removing H2S from gas mixtures which also contain CO2 and so makes it useful for treating natural gas from fields containing both these acidic components.

[0008] The invention also provides a gas separation unit containing a liquid absorbent comprising hindered amino ethers and ether alcohols. Offshore petroleum fluids production installations having a gas separation unit with one of these sorbents are also provided. The separation unit includes a cyclic amine absorption natural gas purification unit for separating acidic gases from produced petroleum gas; this unit has an absorption tower and a regeneration tower through which an aqueous amine absorbent solution is circulated to absorb acidic gases from the gas in the absorption tower and to desorb acidic gases in the regeneration tower. The purified petroleum gas and at least one stream of acidic gas removed from the gas are recovered as separate streams from the regenerator.

Drawings

[0009] The single Figure of the accompanying drawings is a graph showing the

biodegradability of several candidate compounds as reported below.

Detailed Description

General Processing Features

[0010] The acid gas sorbents used in the present gas separation process are normally used in the form of aqueous solutions which can be circulated in the normal type of continuous cyclic amine gas purification unit mentioned briefly above, comprising essentially an absorber tower in which the aqueous amine solution is contacted in countercurrent flow with the incoming gas mixture. The liquid amine stream is then passed to a regenerator in which the sorbed gases are desorbed by a change in conditions, typically a reduction of pressure or an increase in temperature in a separate tower although stripping with another gas stream may also be utilized; the regenerated sorbent solution and the desorbed gases leave the regenerator tower as separate streams. The present amine sorbents can be used in the same manner as conventional amine sorbents and consequently, similar operating practices in the units containing these sorbents can be followed.

[0011] The processed gas mixtures include H2S, and may optionally include other acidic gases such as CO2, SO2, COS, HCN, as well as non-acidic gases such as N2, CH4, H2, CO, H2O, C2H4, NH3, and the like. High selectivity for H2S absorption is favored for the present purposes although less selective absorption is not excluded when required by the feed gas or purification needs. If processing conditions are adjusted non-selective removal of the acid gas components from the non-acidic components may be achieved with subsequent separation of the acidic gases one from another, e.g., separation of H2S from CO2, allowing the CO2 to be re-injected for reservoir pressure maintenance.

[0012] The preferred absorbents used in the separation units are the severely sterically hindered amino ethers, ether alcohols and alkoxy amino ethers, with especial preference given to the amino ether derivatives of triethylene glycol.

[0013] The hindered amine ethers are used in the form of aqueous solutions, typically from about 0.1 to 5M concentration in order to secure adequate loading; variations both within this range and outside it may be made according to individual processing requirements, e.g., concentration of gas species in total gas flow, size of unit, etc. In most cases, the rich solution will have an amine concentration of 0.05 to 2.5 M. Conditions in the separation unit will be typical of those used in conventional amine gas purification processes, for example, in temperature swing operation, sorption temperatures are typically in the range of 30-50°C, more usually 40-50°C and desorption temperatures typically at 60 to 140°C, e.g., 100- 125°C. In pressure swing operation the sorption and desorption pressures are usually set by the pressure of the incoming feed stream and perhaps also by any requirement for the product stream.

[0014] A typical procedure for the selective H2S removal phase of the process comprises selectively absorbing H2S in countercurrent contact of the gaseous mixture is described in US 2009/00308248 to which reference is made for this description.

Production Installations

[0015] The gas purification or separation unit is situated in a marine, offshore location, typically on an offshore gas or crude oil production platform. In the case of a platform producing from an oilfield, the gas will be the natural hydrocarbon gases which are co- produced with the crude oil and which are separated from the oil on the platform to stabilize the liquid before transport either by pipeline or by offloading onto a transfer vessel.

Production platforms may be fixed to the ocean floor as with the familiar and conventional rigid (concrete or steel) leg platforms or the concrete gravity base structures such as the Condeep platforms used in locations usually no more than 200 m in depth although some Condeep structures have been installed in about 350 m of water. Fixed platforms of this type have usually provided adequate space for processing equipment. In deeper water, for example, over 500 m depth, fixed platforms are not economically feasible and floating production, storage and offloading structures tethered to the seabed in a manner that eliminates most vertical movement of the structure, such as tension leg platforms, SPAR or Deep Draft Caisson Vessels (DDCVs), are used at greater depths up to about 2,000 m with one currently placed in over 2400 m (Perdido SPAR in the Gulf of Mexico in 2,438 meters of water). The gas processing unit and related equipment will be installed on the structure of whatever kind in a manner conformable to space and stability requirements. The produced gases may be handled according to the location with close offshore platforms discharging the purified natural gas into the pipeline to shore and, when pipelining to shore is not an option as in the deepwater locations, to the related storage facilities either on the same platform or on another nearby storage facility. CO2 is frequently re-injected into the formation to improve recovery of the oil or gas and for this purpose, the CO2 will be sent to the re-injection compressor equipment. Separated H2 may be handled in the same way or, if possible, treated in a Claus plant and the product sulfur stored for later disposal. On far offshore installations not linked to shore by pipeline, gas liquefaction facilities can be provided to store the hydrocarbon gases as well as separated gases pending transfer to a vessel for transport ashore.

Absorbents

[0016] One class of H2S selective absorbents which are predicted to exhibit favorable environmental characteristics, particularly aquatic toxicity, are the hindered amine alkylsulfonate and alkylphosphonate salts which are described in US 2009/0308248, to which reference is made for a description of these salts as well as of their synthesis and use in selective gas separation processes. Briefly, the salts are generally represented by the following formulae:

Figure imgf000008_0001

in which R1, R2, R3 and R4 are the same or different and selected from H, C1-C9 substituted or unsubstituted straight or C3-C9 substituted or unsubstituted branched chain alkyl, C3-C9 cycloalkyl, C6-C9 aryl, alkylaryl, arylalkyl, C2-C9 straight or branched hydroxyalkyl, cycloalkyl and mixtures thereof provided that both R1 and R2 are not hydrogen and, when n is 2 or more, R3 and R4 on adjacent carbon or on carbons separated by one or more carbons, can be a cycloalkyl or aryl ring and, when the substituents are substituted, they are heteroatom containing substituents, preferably an -NR5R6 group wherein R5 and R6 are the same or different and are selected from H, C1-C9 straight or C3-C9 branched chain alkyl, C3-C9 cycloalkyl, C6-C9 aryl, alkylaryl, arylalkyl, C2-C9 straight or branched chain hydroxyalkyl, cycloalkyl, provided that R5 and R6 are not both H, and further, when R1 is H, and n is 2 or more, R2 and R3 or R4 on the carbon at least one carbon removed from the aminic nitrogen can form a ring;

n is an integer of 1 or more, preferably 1 to 4, more preferably 2 to 4;

metal cation is one or more monovalent, divalent or trivalent metal cation(s) sufficient to satisfy the valence requirements of the anion(s), for example, magnesium, barium, sodium, lithium, potassium or calcium with preference for sodium and potassium. Salts formed from divalent cations can be half- or full-salts.

[0017] R1 and R2 (R1 and R2 are not both hydrogen) are preferably selected from H, C4-C6 alkyl, more preferably C4-C6 branched chain alkyl, most preferably tertiary-butyl. R3and R4 are normally H or C2-C3 alkyl. The value of n is preferably from 1 to 4, most preferably 2 or 3.

[0018] For optimal sorption of the acidic component(s) of the gas mixture, it is necessary to use the salts, preferably the alkali metal salts in order to maintain a reserve of alkalinity in the sorbent solution: the free acids are relatively less effective.

[0019] The sulfonate and phosphonate salts may be synthesized by the methods described in US 2009/0308248 to which reference is made for a description of such methods.

[0020] The preferred absorbent materials for offshore use are the severely sterically hindered amino ethers and amino alcohols of polyalkyleneglycols, especially diethylene glycol and, more preferably triethylene glycol. These have been shown to be selective for absorption of H2S in the presence of C02 and other acidic gases in mixtures with non-acidic gases. The hindered amino derivatives of triethylene glycol have been found to be particularly favorable from the environmental point of view. These absorbents have been found to exhibit high selectivity for H2S absorption in the presence of acidic gases such a C02 and from non-acidic gases. [0021] The preferred amino ethers for offshore application are defined by the formula:

Figure imgf000010_0002

where R1 is a secondary or tertiary alkyl group of 3 to 8 carbon atoms, preferably a tertiary group of 4 to 8 carbon atoms, Y is H or alkyl of 1 to 6 carbon atoms, n is a positive integer from 3 to 8 and x is a positive integer from 3 to 6. The preferred R1 group is tertiary butyl and the most preferred amino ethers are those derived from triethylene glycol (n is 2, x is 3). When Y is H, the amino ether is an amino ether alcohol such as tert-butylamino ethoxyethoxyethanol, derived from triethylene glycol; when Y is alkyl, preferably methyl, the amino ether is an alkoxy amino ether, with preference for tert-butylamino methoxy- ethoxyethoxyethanol. The monoamino ethers may be used in blends with diamino ethers in which the terminal OH group of the ether alcohol or the terminal alkoxy group of the alkoxy amino ether is replaced by a further hindered amino group as expressed in the formula:

Figure imgf000010_0003

where R1, n and x are as defined above and R2, which may the same or different to R1, is a secondary or tertiary alkyl group of 3 to 8 carbon atoms. A preferred diamino ether of this type is bis-(t-butylamino ethoxy) ethane which may conveniently be used as a mixture of ferf-butylamino methoxy-ethoxyethoxyethanol and bis-(t-butylamino ethoxy) ethane.

[0022] Preferred examples of these amino ethers are disclosed in U.S. Patents Nos.

4,405,583; 4,405,585, 4,471 , 138, 4,894, 178 and U.S. Patent Publication 2010/0037775, to which reference is made for a full description of these materials, their synthesis and their use in selective acidic gas separation processes. Their disclosures are summarized below for convenience.

[0023] US 4,405,583: The hindered diamino ethers disclosed in this patent are defined by the formula:

Figure imgf000010_0001
where R1 and R8 are each Ci to C8 alkyi and C2 to C8 hydroxyalkyi groups, R2, R3, R4, R5,R6, and R7 are each hydrogen, C1-C4 alkyi and hydroxyalkyi groups, with certain provisos to define the adequately hindered molecule and m, n, and p are integers from 2 to 4 and o is zero or an integer from 1 to 10. A typical diamino ether of this type is 1 ,2-bis(ferf- butylaminoethoxy) ethane, a diamino derivative of triethylene glycol.

[0024] US 4,405,585: The hindered amino ether alcohols disclosed in this patent are defined by the formula:

Figure imgf000011_0001
where R1 is CrC8 primary alkyi and primary C2-C8 hydroxyalkyi, C3-C8 branched chain alkyi and branched chain hydroxyalkyi and C3-C8 cycloalkyl and hydroxycycloalkyl, R2, R3, R4 and R5 are each hydrogen, C1-C4 alkyi and C1-C4 hydroxyalkyi radicals, with the proviso that when R1 is a primary alkyi or hydroxyalkyi radical, both R2 and R3 bonded to the carbon atom directly bonded to the nitrogen atom are alkyi or hydroxyalkyi radicals and that when the carbon atom of R1 directly bonded to the nitrogen atom is secondary at least one of R2 or R3 bonded to the carbon atom directly bonded to the nitrogen atom is an alkyi or hydroxyalkyi radical, x and y are each positive integers from 2 to 4 and z is an integer from 1 to 4. Exemplary compounds of this type include the amino ether alcohol tert- butylaminoethoxyethanol, a derivative of diethylene glycol.

[0025] US 4,471 , 138: This patent discloses the desirability of using a combination of a diamino ether with an aminoether alcohol. The two compounds are represented by the respective formulae:

Figure imgf000011_0002
where x is an integer ranging from 2 to 6. This mixture can be prepared in the novel one- step synthesis, by the catalytic tertiary butylamination of a polyalkenyl ether glycol, HO-(CH2CH2O)x-CH2CH2-OH, or halo alkoxyalkanol. For example, a mixture of bis-(ferf- butylaminoethoxy)ethane (BTEE) and ethoxyethoxyethanol-ferf-butylamine (EEETB) can be obtained by the catalytic fert/ary-butylamination of triethylene glycol. The severely hindered amine mixture, e.g., BTEE/EEETB, in aqueous solution can be used for the selective removal of H2S in the presence of C02 and for the removal of H2S from gaseous streams in which H2S is the only acidic component, as is often the case in refineries.

[0026] US 4,894, 178: A specific combination of diamino ether and aminoalcohol represented by the respective formulae:

Figure imgf000012_0001
with x being an integer ranging from 2 to 6 and the weight ratio of the first amine to the second amine ranging from 0.43:1 to 2.3:1 . This mixture can be prepared in the one-step synthesis, by the catalytic tertiary-butylamination of the corresponding polyalkenyl ether glycol, for example, by the catalytic tertiary-butylamination of triethylene glycol. This mixture is one of the preferred absorbents for use in offshore gas processing.

[0027] US 2010/0037775: The reaction of a polyalkenyl ether glycol with a hindered amine such as ferf-butylamine is improved by the use of an alkoxy-capped glycol. In the case of alkoxy DEG, the capped glycol now precludes the formation of an unwanted cyclic byproduct, ferf-butyl morpholine (TBM). A preferred capped glycol is methoxy-triethylene glycol although the ethoxy-, propoxy- and butoxy homologs may also be used. The reaction between monomethoxy triethylene glycol and ferf-butylamine is shown to produce MEEETB almost exclusively, in -95% yield, eliminating the need for extensive distillation to remove the product.

[0028] The amino ether compounds may be used in conjunction with other related materials such as an amine salt as described in U.S. Patent No. 4,618,481 . The severely sterically hindered amino compound can be a secondary amino ether alcohol or a disecondary amino ether. The amine salt can be the reaction product of the severely sterically hindered amino compound, a tertiary amino compound such as a tertiary alkanolamine or a triethanolamine, with a strong acid, or a thermally decomposable salt of a strong acid, i.e., ammonium salt or a component capable of forming a strong acid.

[0029] Similarly, U.S. Pat. No. 4,892,674 discloses a process for the selective removal of H2S from gaseous streams using an absorbent composition comprising a non-hindered amine and an additive of a severely-hindered amine salt and/or a severely-hindered aminoacid. The amine salt is the reaction product of an alkaline severely hindered amino compound and a strong acid or a thermally decomposable salt of a strong acid, i.e., ammonium salt.

Selectivity of Candidate Compounds

[0030] Three characteristics which are important in determining the effectiveness of the amino compounds herein for H2S removal are "selectivity", "loading" and "capacity".

"Selectivity" is defined as the mole ratio fraction of the H2S to the CO2 in the liquid (sorbent solution) phase to the mole ratio fraction of the H2S to the CO2 in the gaseous phase. The higher this fraction, the greater the selectivity of the absorbent solution for the H2S in the gas mixture. "Loading" is the concentration of the H2S and CO2 gases physically dissolved and chemically combined in the absorbent solution expressed in moles of gas per moles of the amine. The amino compounds used in the present invention typically have a "selectivity" of not substantially less than 10 at a "loading" of 0.1 moles, preferably, a "selectivity" of not substantially less than 10 at a loading of 0.2 or more moles of H2S and CO2 per moles of the amino compound. "Capacity" is defined as the moles of H2S loaded in the absorbent solution at the end of the absorption step minus the moles of H2S loaded in the absorbent solution at the end of the desorption step. High capacity enables one to reduce the amount of amine solution to be circulated and use less heat or steam during regeneration.

Selectivity = (H2S/CO2) in solution/(H2S/CO2) in feed gas

Loading = Moles H2S/Moles absorbent compound

Capacity = Moles H2S absorbed / Moles H2S after desorption

Moles H2S absorbed The selectivity of the preferred amino glycol derivatives is demonstrated by comparison of the following absorbents:

EETB Ethoxyethanol-tert-butylamine (tert-butylamino-ethoxy-ethanol)

MEETB Methoxyethoxyethanol-tert-butylamine

EEETB Ethoxyethoxyethanol-tert-butylamine

BEETB Butoxyethoxyethanol-tert-butylamine

MEEETB Methoxyethoxyethoxyethanol-tert-butylamine

TEGTB Triethylene glycol-t-butylamine (t-butylaminoethoxyethoxyethanol)

Bis-SE Bis-(t-butylaminoethyl) ether

Bis-TEGTB Bis-(t-butylamino ethoxy) ethane (bis-(t-butylamino) triethylene glycol)

[0031] Experimental Procedure

1. Absorption tests were carried out at 35° C. on 0.15 M aqueous solutions of absorbent using a gas mixture of nitrogen:carbon dioxide:hydrogen sulfide of 89:10:1 for 2 hours.

2. Desorption experiments were run at 85° C. in flowing nitrogen for 2 hours at the same flow rate as the test gas mixture.

[0032] The results are shown in Table 1 below.

Figure imgf000015_0001

[0033] As can be seen, the methoxy-, ethoxy- and butoxy-substituted diethylene and triethylene glycol-t-butyl amines have higher degrees of selectivity as compared to the EETB and its diamino derivative (Bis-SE, bis-(t-butylaminoethyl) ether) and have at least equivalent and in most cases superior capacity and superior selectivity after regeneration than the EETB and the corresponding diamino bis-SE.

Assessment of Health and Environmental Aspects of Candidate Compounds

[0034] To assess the toxicity potential and environmental fate properties of various selective absorbents, quantitative structure activity relationships (QSARs) were applied together with experimental confirmation of aquatic toxicity.

[0035] The chemical structures of candidate absorbents were run through a series of computer models for comparative purposes. Physical chemical properties (i.e., vapor pressure, water solubility, and octanol/water partition coefficient) were estimated using two models, EPISuite1 and SPARC2. Biodegradation potential was determined using BlOWin, a subroutine of EPISuite.

[0036] The four candidates in the evaluation were:

Candidate A EETB

Candidate B MEEETB

Candidate C TEGTB

Candidate D Bis-TEGTB

Biodegradation

[0037] Table 2 below compares physical chemical properties (VP, WS, Log Kow) of the candidate substances. The octanol/water partition coefficient (or Log Kow) of all candidate substances indicates these substances would not be expected to pose a bioaccumulation concern.

Figure imgf000016_0001
[0039] The biodegradation of the four candidates was tested by Manometric Respirometry following OECD TG 301 F [at 20°C] with the results in Table 3 below and in the

accompanying Figure.

Figure imgf000018_0001
Figure imgf000019_0002

[0040] The continued upward trend in the biodegradation of the mixture of C and D indicates that degradative elimination from the environment can be expected with increasing time.

Aquatic Toxicity

[0041] Aquatic toxicity predictions for fish, invertebrates (Daphnia) and algae were made using ECOSAR, also a subroutine of EPISuite that estimates aquatic toxicity and verified experimentally. The commercial TOPKAT® 4model was used to estimate mammalian toxicity endpoints.

[0042] The acute aquatic toxicity predictions in Table 4 indicate absorbents A, B, E and F exhibit toxicity to at least one aquatic organism in the 10-100 mg/l range . Fish appear to be consistently less sensitive than daphnids or algae.

Figure imgf000019_0001

[0043] Aquatic toxicity was tested experimentally using the OECD TG 202 - Daphnia sp. Acute Immobilisation Test The results are given below in Table 5.

Table 5

Aquatic Toxicity

4 Accelrys Discovery Studio Predictive Toxicology tool, Discovery Studio TOPKAT.

Figure imgf000020_0001

[0044] The classification "Harmful to aquatic organisms" signifies that the compounds in question may be used in the offshore environment subject to mitigation, for example, secondary treatment or dilution. None were deemed toxic, barring their use. Based on biodegradability and aquatic toxicity predictions none of the candidate substances are expected to require a negative environmental label (e.g., the European dead fish/dead tree symbol) although absorbent D appeared on the basis of the predictions to be least preferred from an environmental perspective.

Mammalian Toxicity

The TOPKAT® predictions for mammalian toxicity endpoints given in Table 6 indicate absorbents A, and C have a low potential for acute toxicity in rats, while absorbents B and D show predicted acute toxicity in the range of 1000 to 2000 mg/kg, which would put them in the harmful category. Chronic toxicity in rats is reported as the Lowest Observed Adverse Effect Level (LOAEL), which is the lowest dose level, in weight of chemical to body weight units, which is predicted to cause an adverse effect. The Ocular Irritancy module computes the probability of a chemical structure being an ocular irritant in the Draize test. All candidates are expected to cause severe eye irritation. The Developmental Toxicity Potential module of the TOPKAT package predicts that candidate A derived from diethylene glycol is likely to be less favorable than the triethylene glycol derivatives.

[0045] Carcinogenic potential is predicted using the NTP Rodent Carcinogenicity Module in TOPKAT and comprises four statistically significant quantitative structure-toxicity relationship models. These models are derived from 366 uniform rodent carcinogenicity studies conducted by the National Cancer Institute. Positive results listed in Table 4 below indicate the potential for the candidate to be carcinogenic or not carcinogenic in either rats or mice. Results scored as indeterminate indicate insufficient evidence to score either as positive or negative. The model also predicts that none of the candidate absorbents are expected to be skin sensitizers, nor are they expected to be mutagens.

Figure imgf000021_0001

Claims

Claims
1. A marine offshore petroleum fluid production installation including a cyclic amine absorption natural gas purification unit for separating acidic gases from produced petroleum gas, the unit comprising an absorption tower and a regeneration tower through which an aqueous amine absorbent solution is circulated to absorb acidic gases from the gas in the absorption tower and to desorb acidic gases in the regeneration tower to produce a stream of purified gas and at least one stream of acidic gas removed from the gas, the aqueous amine absorbent solution comprises an aqueous solution of a severely sterically hindered amino ether of the formula:
Figure imgf000022_0001
where R1 is a secondary or tertiary alkyi group of 3 to 8 carbon atoms, Y is H or alkyl of 1 to 6 carbon atoms, n is a positive integer from 3 to 8 and x is a positive integer from 3 to 6.
2. A marine offshore petroleum fluid production installation according to claim 1 in which R1 is a branched secondary or tertiary alkyi group of 3 to 9 carbon atoms.
3. A marine offshore petroleum fluid production installation according to claim 2 in which R1 is tertiary butyl.
4. A marine offshore petroleum fluid production installation according to claim 3 in which n is 2.
5. A marine offshore petroleum fluid production installation according to claim 1 in which x is 3.
6. A marine offshore petroleum fluid production installation according to claim 1 in which Y is H
7. A marine offshore petroleum fluid production installation according to claim 6 in which the amino ether is tert-butylamino ethoxyethoxyethanol.
8. A marine offshore petroleum fluid production installation according to claim 1 in which Y is methyl.
9. A marine offshore petroleum fluid production installation according to claim 1 in which the amino ether is ferf-butylamino methoxy-ethoxyethoxyethanol.
10. A marine offshore petroleum fluid production installation according to claim 1 in which the absorbent solution also comprises a diamino ether of the formula:
Figure imgf000023_0001
where R1, n and x are as defined in claim 1 and R2, which may the same or different to R1, is a secondary or tertiary alkyl group of 3 to 8 carbon atoms.
1 1 . A marine offshore petroleum fluid production installation according to claim 1 in which the absorbent solution also comprises bis-(t-butylamino ethoxy) ethane..
12. A marine offshore petroleum fluid production installation according to claim 1 1 in which the absorbent solution comprises ferf-butylamino methoxy-ethoxyethoxyethanol and bis-(f-butylamino ethoxy) ethane.
13. A process for the selective absorption of normally gaseous acidic components from hydrocarbon gas mixtures containing both the acidic component and gaseous non-acidic components, which process is carried out in a gas separation unit located at an offshore marine petroleum fluid production installation in which an aqueous amine absorbent solution is circulated in a cyclic amine absorption natural gas purification unit to absorb acidic gases from the hydrocarbon gas in an absorption tower and to desorb acidic gases in a regeneration tower to produce a stream of purified hydrocarbon gas and at least one stream of acidic gas removed from the hydrocarbon gas, the aqueous amine absorbent solution being an aqueous solution of a severely sterically hindered amino ether of the formula:
Figure imgf000023_0002
where R1, Y, n and x are as defined in anyone of the preceding claims.
14. A process according to claim 13 in which H2S is selectively removed from a produced natural gas stream which contains H2S and CO2.
15. A process for purifying a stream of natural gas produced at a marine offshore petroleum fluid production installation including a cyclic amine absorption natural gas purification unit for separating acidic gases from produced natural gas, the unit comprising an absorption tower and a regeneration tower through which an aqueous amine absorbent solution is circulated to absorb acidic gases from the natural gas in the absorption tower and to desorb acidic gases in the regeneration tower to produce a stream of purified gas and at least one stream of acidic gas removed from the natural gas, the aqueous amine absorbent solution being an aqueous solution of a hindered, wherein the absorbent solution also comprises a diamino ether of the formula:
Figure imgf000024_0001
where R1, Y, n and x are as defined in claim 1 and R2 is as defined in anyone of claims 1 - 12.
16. A process according to claim 15 which selectively absorbs H2S from the natural gas.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013138443A1 (en) * 2012-03-14 2013-09-19 Exxonmobil Research And Engineering Company Amine treating process for acid gas separation using blends of amines and alkyloxyamines
US20150375165A1 (en) * 2013-09-16 2015-12-31 Savannah River Nuclear Solutions, Llc Mass Transfer Apparatus and Method for Separation of Gases
EP3034154A1 (en) 2014-12-19 2016-06-22 Haldor Topsøe A/S A method for removing hydrogen sulfide from an acid gas

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2817397B1 (en) * 2012-02-23 2019-07-31 FMC Kongsberg Subsea AS Offshore processing method and system
CA2917802A1 (en) * 2013-07-29 2015-02-05 Exxonmobil Research And Engineering Company Separation of hydrogen sulfide from natural gas
SG11201601231UA (en) * 2014-01-20 2016-03-30 Ptt Public Company Ltd A system and a process for enhancing efficiency of co2 removal from natural gas stream
CA3061843A1 (en) * 2017-05-15 2018-11-22 Basf Se Absorbent and process for selectively removing hydrogen sulfide

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4112052A (en) 1975-06-26 1978-09-05 Exxon Research & Engineering Co. Process for removing carbon dioxide containing acidic gases from gaseous mixtures using aqueous amine scrubbing solutions
US4405585A (en) 1982-01-18 1983-09-20 Exxon Research And Engineering Co. Process for the selective removal of hydrogen sulfide from gaseous mixtures with severely sterically hindered secondary aminoether alcohols
US4405581A (en) 1982-01-18 1983-09-20 Exxon Research And Engineering Co. Process for the selective removal of hydrogen sulfide from gaseous mixtures with severely sterically hindered secondary amino compounds
US4405583A (en) 1982-01-18 1983-09-20 Exxon Research And Engineering Co. Process for selective removal of H2 S from mixtures containing H22 using di-severely sterically hindered secondary aminoethers
US4471138A (en) 1982-01-18 1984-09-11 Exxon Research And Engineering Co. Severely sterically hindered secondary aminoether alcohols
US4618481A (en) 1985-08-30 1986-10-21 Exxon Research And Engineering Co. Absorbent composition containing a severely hindered amino compound and an amine salt and process for the absorption of H2 S using the same
US4892674A (en) 1987-10-13 1990-01-09 Exxon Research And Engineering Company Addition of severely-hindered amine salts and/or aminoacids to non-hindered amine solutions for the absorption of H2 S
US4894178A (en) 1987-10-13 1990-01-16 Exxon Research And Engineering Company Absorbent composition containing severely-hindered amine mixture for the absorption of H2 S
EP0737094A1 (en) * 1993-12-27 1996-10-16 Norsk Hydro Asa Purification of natural gas
US20080210092A1 (en) * 2007-02-02 2008-09-04 Chevron U.S.A. Inc. Methods and apparatus for removing acid gases from a natural gas stream
US20090308248A1 (en) 2005-08-09 2009-12-17 Michael Siskin Absorbent composition containing molecules with a hindered amine and a metal sulfonate, phosphonate or carboxylate structure for acid gas scrubbing process
US20100037775A1 (en) 2005-08-09 2010-02-18 Exxon-Mobil Research And Engineering Company Alkylamino alkyloxy (alcohol) monoalkyl ether for acid gas scrubbing process
US20110168019A1 (en) * 2008-10-14 2011-07-14 Paul Scott Northrop Removal of Acid Gases From A Gas Stream
WO2012074807A1 (en) * 2010-12-01 2012-06-07 Huntsman Petrochemical Llc Sterically hindered amines and associated methods

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2911516B1 (en) * 2007-01-19 2009-11-13 Total Sa Process for purifying a gaseous mixture containing acidic gases

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4112052A (en) 1975-06-26 1978-09-05 Exxon Research & Engineering Co. Process for removing carbon dioxide containing acidic gases from gaseous mixtures using aqueous amine scrubbing solutions
US4405585A (en) 1982-01-18 1983-09-20 Exxon Research And Engineering Co. Process for the selective removal of hydrogen sulfide from gaseous mixtures with severely sterically hindered secondary aminoether alcohols
US4405581A (en) 1982-01-18 1983-09-20 Exxon Research And Engineering Co. Process for the selective removal of hydrogen sulfide from gaseous mixtures with severely sterically hindered secondary amino compounds
US4405583A (en) 1982-01-18 1983-09-20 Exxon Research And Engineering Co. Process for selective removal of H2 S from mixtures containing H22 using di-severely sterically hindered secondary aminoethers
US4471138A (en) 1982-01-18 1984-09-11 Exxon Research And Engineering Co. Severely sterically hindered secondary aminoether alcohols
US4618481A (en) 1985-08-30 1986-10-21 Exxon Research And Engineering Co. Absorbent composition containing a severely hindered amino compound and an amine salt and process for the absorption of H2 S using the same
US4892674A (en) 1987-10-13 1990-01-09 Exxon Research And Engineering Company Addition of severely-hindered amine salts and/or aminoacids to non-hindered amine solutions for the absorption of H2 S
US4894178A (en) 1987-10-13 1990-01-16 Exxon Research And Engineering Company Absorbent composition containing severely-hindered amine mixture for the absorption of H2 S
EP0737094A1 (en) * 1993-12-27 1996-10-16 Norsk Hydro Asa Purification of natural gas
US20090308248A1 (en) 2005-08-09 2009-12-17 Michael Siskin Absorbent composition containing molecules with a hindered amine and a metal sulfonate, phosphonate or carboxylate structure for acid gas scrubbing process
US20100037775A1 (en) 2005-08-09 2010-02-18 Exxon-Mobil Research And Engineering Company Alkylamino alkyloxy (alcohol) monoalkyl ether for acid gas scrubbing process
US20080210092A1 (en) * 2007-02-02 2008-09-04 Chevron U.S.A. Inc. Methods and apparatus for removing acid gases from a natural gas stream
US20110168019A1 (en) * 2008-10-14 2011-07-14 Paul Scott Northrop Removal of Acid Gases From A Gas Stream
WO2012074807A1 (en) * 2010-12-01 2012-06-07 Huntsman Petrochemical Llc Sterically hindered amines and associated methods

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
KOHL; NEILSEN: "Gas Purification", 1997, GULF PUBLISHING COMPANY

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2013138443A1 (en) * 2012-03-14 2013-09-19 Exxonmobil Research And Engineering Company Amine treating process for acid gas separation using blends of amines and alkyloxyamines
US20150375165A1 (en) * 2013-09-16 2015-12-31 Savannah River Nuclear Solutions, Llc Mass Transfer Apparatus and Method for Separation of Gases
US9868084B2 (en) * 2013-09-16 2018-01-16 Savannah River Nuclear Solutions, Llc Mass transfer apparatus and method for separation of gases
EP3034154A1 (en) 2014-12-19 2016-06-22 Haldor Topsøe A/S A method for removing hydrogen sulfide from an acid gas
WO2016096447A1 (en) 2014-12-19 2016-06-23 Haldor Topsøe A/S A method for removing hydrogen sulfide from an acid gas

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