Abstract: In a natural gas dehydration system, a heat exchanger has first and second passages in thermal communication but fluidly isolated from each other. A pressure reduction valve receives a first stream of natural gas and water vapor from the first passage and outputs a reduced temperature and pressure first stream to a separator which separates at least part of the water from the first stream to form a second stream of natural gas and water vapor that is output via the second passage to a distribution pipeline or a storage system. A temperature sensor senses a temperature of the first stream and a controller controls a valve coupled in parallel with the second passage to be in an open or closed state for passage or blocking of at least part of the second stream therethrough based on a temperature of the first stream determined by the temperature sensor.

Abstract: In one embodiment, a gas purification system is provided. The system includes a first section having a first solvent path and a first gas path. The first gas path is configured to flow a stripping gas to remove hydrogen sulfide (H2S) and carbon dioxide (CO2) from the first solvent path in a first vessel to produce a first gas mixture. The system also includes a second section having a second solvent path. The second solvent path is configured to flow a second solvent mixture to remove H2S from the first gas mixture and CO2 from the second solvent mixture within a second vessel. The second solvent mixture has a solvent saturated in CO2 at a first pressure, the second vessel is operated at a second pressure, and the first and second pressures are within approximately 20% of one another.

Abstract: A method for removing acid gases from a fluid flow using an absorbent including an aqueous solution with at least two different amines. An amine in a proportion of greater than 50 wt. % of the total amine amount in the aqueous solution is the first amine component in the aqueous solution, and a sterically hindered amine in a proportion of less than 50 wt. % is the second amine component in the aqueous solution. The fluid flow is brought into contact with the absorbent at a partial pressure of <200 mbar.

Abstract: A gas condensate production plant comprises a plurality of separation units in which C2 and/or C3 lighter components are stripped from the separator feeds using compressed heated stripping vapor produced from the feed in respective downstream separation units. Contemplated plants substantially reduce heating and cooling duties by using the waste heat from the compressor discharges in the separation process. Furthermore, the multi-stage fractionation according to the inventive subject matter provides improved gas condensate recovery at reduced energy costs.

Abstract: The present invention describes a method for recovery of high purity carbon dioxide, which is substantially free of nitrogen oxides. This high purity carbon dioxide is obtained by introducing into the method a step in which carbon dioxide absorbed in an absorbing agent is flashed. The present invention also discloses a plant for recovery of said high purity carbon dioxide comprising an absorption column, a flash column, a stripper column, and a down stream purification unit comprising a washing column, a dehydrator, a condenser and a distillation unit.

Abstract: From the CO2-containing stream of process gas obtained in a process for the treatment of a CO2-containing stream of process gas, which is obtained in the production of pure synthesis gas from raw gas in the partial oxidation of heavy oils, petroleum coke or wastes, or in the gasification of coal, or when processing natural gas or accompanying natural gas, CO2 is removed physisorptively or chemisorptively, and the solvent loaded with CO2 is expanded to a lower pressure for the desorption of CO2. In order to generate CO2 as pure as possible, the contaminated CO2 is condensed to at least 60 bar[a] or below its critical temperature to at least 70 bar[a], and the impurities contained in the liquid CO2 are removed by stripping with gaseous CO2 guided in counterflow.

Abstract: A method of assembling an acid gas component reduction system includes coupling at least one acid removal system in flow communication with at least one first synthetic gas (syngas) stream with at least one acid gas component having a first acid gas component concentration. The method also includes coupling at least one integral absorber in flow communication with the at least one acid removal system. The method further includes configuring the at least one integral absorber such that substantially continuous service of the at least one integral absorber facilitates producing a second syngas stream having a second acid gas component concentration that is less than the first acid gas component concentration.

Abstract: A process and system (100) for removing contaminants from a solution to regenerate the solution within the system. The process includes providing a solution (165) from a wash vessel (160) to a stripping column (181), the solution (165) including contaminants removed from a flue gas stream (150) present in the wash vessel (160) and contacting the solution with steam (185) inside the stripping column (181) thereby removing the contaminants from the solution and regenerating the solution. The stripping column (181) is operated at a pressure less than about 700 kilopascal.

Abstract: The invention provides a process for producing purified gas from feed gas comprising H2S, CO2 and HCN and/or COS, the process comprising the steps of: (a) contacting feed gas comprising H2S, CO2 and HCN and/or COS with a HCN/COS hydrolysis sorbent in the presence of water in a HCN/COS hydrolysis unit, thereby obtaining gas depleted in HCN and/or COS; (b) contacting the gas depleted in HCN and/or COS with absorbing liquid in an H2S/CO2 absorber to remove H2S and CO2, thereby obtaining the purified gas and absorbing liquid rich in H2S and CO2; (c) heating and de-pressurizing at least part of the absorbing liquid rich in H2S and CO2 to obtain hot flash gas enriched in CO2 and absorbing liquid enriched in H2S; (d) contacting the absorbing liquid enriched in H2S at elevated temperature with a stripping gas, thereby transferring H2S to the stripping gas to obtain regenerated absorbing liquid and stripping gas rich in H2S; and (e) leading at least part of the flash gas enriched in CO2 to the HCN/COS hydrolysis unit

Abstract: In one embodiment, a gas purification system is provided. The system includes a first solvent section having a first carbon dioxide (CO2) absorber, a hydrogen sulfide (H2S) absorber, and a first solvent path that routes a first solvent through the first CO2 absorber and the H2S absorber. The gas purification system also includes a second solvent section having a second carbon dioxide (CO2) absorber and a second solvent path that flows a second solvent through the second CO2 absorber. The gas purification system has a gas path though the first and second solvent sections, wherein the first and second solvent paths are separate from one another, and the first and second solvents are different from one another.

Abstract: Capturing a target gas includes contacting a gas mixture including a target species with an aqueous solution including a buffer species, and transferring some of the target species from the gas mixture to the aqueous solution. The target species forms a dissolved target species in the aqueous solution, and the aqueous solution is processed to yield a first aqueous stream and a second aqueous stream, where the equilibrium partial pressure of the target species over the second aqueous stream exceeds the equilibrium partial pressure of the target species over the first aqueous stream. At least some of the dissolved target species in the second aqueous stream is converted to the target species, and the target species is liberated from the second aqueous stream. The target species can be collected and/or compressed for subsequent processing or use.

Abstract: Acid gas is removed from a high pressure feed gas that contains significant quantities of CO2 and H2S. In especially preferred configurations and methods, feed gas is contacted in an absorber with a lean and an ultra-lean solvent that are formed by flashing rich solvent and stripping a portion of the lean solvent, respectively. Most preferably, the flash vapors and the stripping overhead vapors are recycled to the feed gas/absorber, and the treated feed gas has a CO2 concentration of less than 2 mol % and a H2S concentration of less than 10 ppmv, and more typically less than 4 ppmv.

Abstract: A method for removing acid gases from a fluid flow using an absorbent including an aqueous solution with at least two different amines. An amine in a proportion of greater than 50 wt. % of the total amine amount in the aqueous solution is the first amine component in the aqueous solution, and a sterically hindered amine in a proportion of less than 50 wt. % is the second amine component in the aqueous solution. The fluid flow is brought into contact with the absorbent at a partial pressure of <200 mbar.

Abstract: The invention involves a process for maintaining a low level of carbon monoxide in a carbon dioxide product stream and also for keeping the carbon monoxide out of the fully shifted synthesis gas. The overall process is a process for treating both fully shifted and partially shifted or unshifted synthesis gas. The carbon monoxide is separately removed by a carbon monoxide stripping column and returned to the partially shifted or unshifted synthesis gas which can then undergo a shift reaction to convert the carbon monoxide to carbon dioxide.

Abstract: The invention relates to a process for remediation of a fluid contaminated with alkylene oxide, involving contacting the contaminated fluid with an aqueous absorbent to yield a fat absorbent having absorbed fluid, conferring intimate contact of fat absorbent and alkylene oxide and conversion of alkylene oxide; and, an apparatus for remediation of the fluid which has a converter having inlet means connected to the outlet of a fluid absorber for contacting fluid and aqueous absorbent, a holding unit having a volume V for the fat absorbent, and outlet means connected to the inlet of a fluid desorber.

Abstract: In a method for purifying biogas, components present in the biogas, such as carbon dioxide, sulfur compounds and ammonia, are separated in a plurality of different process stages. The method is characterized by low energy consumption and an increase in methane concentration of at least 10% while keeping methane losses low. In a first purifying step, carbon dioxide, hydrogen sulfide, ammonia and other organic water-soluble substances in the raw gas are removed at normal pressure or at overpressure of up to 6 bar in a wash column using fresh water, methane gas having a methane concentration of at least 65% is withdrawn at the head of the wash column. Methane and carbon dioxide dissolved in the washing water are sequentially separated from the contaminated washing water discharged from the washing stage in a first stripping column at normal pressure and subsequently in a second stripping column in a vacuum.

Abstract: An acid gas such as carbon dioxide, hydrogen sulfide, or a mixture thereof is removed from gaseous streams using aqueous absorption and stripping processes. By replacing the conventional stripper used to regenerate the aqueous solvent and capture the acid gas with a multipressure stripper (51) that combines acid gas compression with stripping, less energy is consumed. The multipressure stripper is a multistage flash (52, 55, 59) in which the total vapor flow from each stage is compressed and fed to the bottom of the previous flash stage at a higher pressure. In this process, the heat in the water content of the vapor exiting each stage is utilized at a higher pressure in the previous stage. The described stripping process generates the acid gas at a higher pressure without operating the stripper at a higher temperature, thereby reducing the energy consumption of the system.

Abstract: Methods and systems for handling sour carbon dioxide (CO2) streams are provided. In one aspect, a method for sequestering an emissions-heavy gas includes removing at least a portion of an acid gas from a rich solvent in an acid gas stripper to create the emissions-heavy gas, and channeling the emissions-heavy gas to a storage system.

Abstract: The invention relates to a system and a method for control of emission of volatile gases (VOC) from a holding tank (80) for crude oil during unloading, loading and transport/holding of the oil, such as in an oil tank on board an oil tanker, in which a blanket gas is used to regulate pressure and amount of combustible gas and to prevent ingress of oxygen into the mentioned holding tank for crude oil. The system comprises a recovery device (50) for recovery of hydrocarbon gas from the holding tank (80) for crude oil, a storage tank (18) for liquid hydrocarbons under pressure, supplied from the recovery device (50), and that liquid hydrocarbons are fed to an evaporation device (70) set up to convert liquid hydrocarbons to gas form, for use as blanket gas in a holding tank (80) for crude oil.

Abstract: An absorption medium for removing acid gases from a fluid stream comprises an aqueous solution of A) at least one cyclic amine compound having solely tertiary amine groups and/or sterically hindered secondary amine groups and B) at least one cyclic amine compound having at least one sterically unhindered secondary amine group. The absorption medium comprises, e.g., an aqueous solution of A) 1-hydroxyethylpiperidine and/or triethylenediamine and B) piperazine. The absorption medium is particularly suitable for separating off carbon dioxide from flue gases and satisfies the following criteria: (i) sufficient capacity at low CO2 partial pressures; (ii) sufficiently rapid absorption rate at low CO2 partial pressures; (iii) stability toward oxygen; (iv) low vapor pressure for reducing solvent losses; and (v) low energy requirement for regeneration of the absorption medium.

Abstract: An absorber (110) in a gas treatment plant (100) produces a rich solvent (116) that is flashed to produce flashed rich solvent (134D) and recycle gas (132D), wherein the recycle gas (132D) is not mixed with the absorber feed gas (112) as commonly practiced, but mixed with the rich solvent (116). Such configurations exhibit superior rich solvent loading, thereby reducing solvent circulation. Further contemplated gas treatment plants (100)may also include a regenerator (150) in which carbon dioxide from atmospheric flashed vapor (142) of the rich solvent (144) is employed as a stripping gas in a regenerator (150) to strip hydrogen sulfide from the rich solvent (144), and wherein sweet gas (114) is employed to strip the carbon dioxide from the rich solvent (144).

Abstract: A plant includes a vacuum stripper (118) that receives a lean hydrogen sulfide-containing physical solvent (32) and in which substantially hydrogen sulfide-free stripping gas (51,52) is provided by at least one of a high-pressure flash vessel (110) and a medium pressure flash vessel (112). Contemplated configurations advantageously extend the range of use for physical solvents to treat sour gas comprising carbon dioxide and hydrogen sulfide, and can be used to meet most pipeline specification of 4 ppm hydrogen sulfide.

Abstract: A method and apparatus for removing carbon dioxide from a synthesis gas stream containing hydrogen is disclosed. The method includes absorbing the carbon dioxide using a physical solvent under high pressure and then liberating the carbon dioxide in a series of expansion stages where the pressure on the solvent is reduced. The expansion ratio increases with each expansion stage. The apparatus includes expansion stages having throttling devices and expansion tanks operated at increasing expansion ratios. Carbon dioxide is liberated in this manner so as to minimize the energy required compress for transport via a pipe line for sequestration of the gas. Sequestration of the carbon dioxide is preferred to atmospheric venting to curb the release of greenhouse gases.

Abstract: A plant includes an absorber (103) that operates in a gas phase supercritical region and removes an acid gas from a feed stream (9) at high recovery of the feed stream (10) while producing a high purity acid gas stream (36). Particularly preferred plants include gas purification plants that receive a feed gas with at least 5 mol % carbon dioxide at a pressure of at least 3000 psi.

Abstract: A multi-phase separation system utilized to remove contaminants from fluids includes a pre-filtering module for filtering a contaminated fluid to provide a filtered contaminated fluid. A condenser module receives the filtered contaminated fluid and a contaminated gas phase for condensing the contaminated gas phase to a contaminated liquid. A phase reaction chamber converts the filtered contaminated fluid to a contaminated mist wherein the mist is subjected to a low energy, high vacuum environment for providing a first change of phase by separating into a contaminated gas phase and a liquid mist phase. The contaminated gas phase is carried out of the phase reaction chamber by a carrier air. A vacuum pump provides the low energy, high vacuum environment in the phase reaction chamber and delivers the contaminated gas phase to the condenser module for condensation providing a second change of phase.

Abstract: An improved method and structure for purification of an acid gas stream by using raw fuel gas as a stripper to remove the BTEX and VOCs from the liquid amine stream. The improved method is particularly useful for purification of acid gas streams with BTEX contaminant levels in excess of environmentally acceptable levels for standard processing. Raw fuel gas is utilized at moderate temperatures and pressures, the uptake of BTEX and VOCs reduces the level of these compounds in the waste amine stream to environmentally acceptable levels, and the remaining contaminants may then be dealt with by ordinary means. Levels of H2S and CO2. in the liquid amine stream are also reduced.

Abstract: A method for removing residual VOC components from a fluid stream used in the sweetening of sour gas at gas processing plants. In a retrofit configuration, the method includes interposing a supplemental VOC removal station after a primary VOC removal station in an absorbent fluid stream. The absorbent fluid stream incorporates fluid into which sour gas components and VOC have been absorbed from a treated gas stream such as produced natural gas. The primary VOC removal station is configured to remove an initial portion of the absorbed VOC from the absorbent fluid stream. The supplemental VOC removal station is configured to liberate a portion of residual absorbed VOC remaining in the absorbent fluid stream downstream from the primary VOC removal station. Further, the supplemental VOC removal station is configured to avoid liberating absorbed sour gas components from the absorbent fluid stream.

Abstract: Degassing is accomplished by driving a gas-containing solution to a subatmospheric pressure approximately equal to the solution vapor pressure, and maintaining the subatmospheric pressure notwithstanding evolution of gas from the solution. This may be accomplished using a vacuum tower arrangment whereby a column of the gas-containing liquid is drawn to the maximum physically attainable height. So long as the vacuum is coupled to the liquid column above this height (generally on the order of 34 feet, depending on the ambient temperature and the composition of the liquid), the liquid will not be drawn into the vacuum, which creates a non-equilibrium region of extremely low pressure above the liquid that liberates dissolved gases. Moreover, liquid introduced into the low-pressure region above the column will fall onto the column without entering the vacuum system.

Abstract: A system for regenerating chemical solvent loaded with acid gas with improved energy efficiency wherein the chemical solvent is partially flash vaporized, heated, and passed in countercurrent mass transfer contact with nitrogen gas.

Abstract: An improved process for the glycol dehydration of water-containing natural gas comprises contacting the natural gas and glycol in a contacting zone to produce a dried natural gas and a water-rich glycol, and heating the water-rich glycol in a regeneration zone to produce a water-lean glycol for reintroduction into the contacting zone and a water-containing gaseous overhead. The gaseous overhead is partially condensed and the resulting gaseous components are returned to the contacting zone. In a preferred embodiment, the glycol is further purified by contact in a separate stripping column with dry stripping gas under a pressure lower than that of the regeneration zone.