Apparatus and method for gas-liquid separation of a Fischer-Tropsch reactor outlet stream - Patent Application 20070229333

Abstract

a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products from a Fischer-Tropsch reactor and steam to a first gas-liquid separator in which the product stream is separated into a first liquid comprising a first fraction of the hydrocarbon products and a first gas stream comprising the gaseous hydrocarbon products and steam; b) collecting the first liquid at a liquid outlet of the first gas-liquid separator; and c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and passing the first gas stream through a first cooler. d) feeding the first cooled mixture from the first cooler to a second liquid-vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; and e) feeding the liquid in the second liquid-vapor separator to a second liquid-vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water and a second gas stream comprising any remainder of the hydrocarbon product and water vapor. collecting the second liquid at the outlet; f) discharging a second gas stream from the gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; and h) feeding the second cooled mixture from the second cooler to a third gas-liquid separator in which the second cooled mixture is condensed with a carbon dioxide gas. and separating the third liquid comprising a third fraction of the hydrocarbyl product and water, and a third gas stream; i) collecting the third liquid at a liquid outlet of the third gas-liquid separator; and j) discharging the third gas stream from a gas outlet of the third gas-liquid separator, the method further comprising feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated in the decanter into the liquid hydrocarbon product and water.

Description

[Technical field]

[0001] The present invention relates to an apparatus and method for gas-liquid separation, and more particularly to an apparatus and method for separating a product stream containing a hydrocarbon product and water vapor into separate liquid and gas fractions. [Background technology]

[0002] It is known to produce oxygenated organic chemicals by chemical reactions. One well-known method for producing hydrocarbons on an industrial scale is the Fischer-Tropsch process, in which a mixture of carbon monoxide and hydrogen is reacted in a reactor in the presence of a catalyst to produce a reaction product that includes hydrocarbons. The temperatures and pressures used in the Fischer-Tropsch process are such that the reaction product initially exiting the reactor is a mixture of liquid and gaseous hydrocarbon products and water vapor.

[0003] It is desirable to further process the reaction product to separate the waxy products from the lighter hydrocarbon products. Typically, this further processing requires cooling the reaction product. A potential problem is that such cooling can cause the waxy products to solidify and deposit on equipment components, e.g., cooling equipment such as condensers. This can result in equipment blockages that require equipment shutdown to allow removal of the waxy deposits. Shutting down a reactor and restarting it leads to inefficiencies, e.g., due to lost processing time and additional maintenance costs.

[0004] WO 2019 / 016757 describes an apparatus and method for separating a wax product from the product of an isothermal or adiabatic fixed bed reactor configured to carry out a Fischer-Tropsch process. WO 2019 / 016757 attempts to address the problem of wax deposits by providing a first condenser and a second condenser in parallel fluid communication with the isothermal or adiabatic fixed bed reactor. In use, the product from the Fischer-Tropsch process first passes through the first condenser where it is cooled to solidify the wax product and is collected in the first condenser. Once a predetermined amount of wax product has been collected in the first condenser, the product flow is switched to flow the product through the second condenser, allowing for the emptying of the wax product from the first condenser offline. Thus, the use of parallel first and second condensers allows for continuous processing of the product. However, the solution proposed in WO 2019 / 016757 requires the use of parallel condensers, only one of which is in use at any one time, which leads to inefficiencies and additional complexity, capital expenditure and maintenance costs.

[0005] The present invention aims to address at least some of the problems associated with the prior art, or at least to provide a commercially acceptable alternative solution. Summary of the Invention

[0006] One aspect of the present disclosure is a method for producing a method for manufacturing a semiconductor device comprising the steps of: a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products from a Fischer-Tropsch reactor and steam to a first gas-liquid separator in which the product stream is separated into a first liquid comprising a first fraction of the hydrocarbon products and a first gas stream comprising the gaseous hydrocarbon products and steam; b) collecting the first liquid at a liquid outlet of the first gas-liquid separator; c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and passing the first gas stream through a first cooler to apply cooling to the first gas stream to condense the gaseous hydrocarbon product and a portion of the water vapor to form a first cooled mixture; d) feeding the first cooled mixture from the first cooler to a second liquid / vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; e) collecting the second liquid at a liquid outlet of the second gas-liquid separator; f) discharging the second gas stream from a gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; h) feeding the second cooled mixture from the second cooler to a third liquid-vapor separator wherein the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and water, and a third gas stream; i) collecting a third liquid at a liquid outlet of the third gas-liquid separator; j) discharging a third gas stream from a gas outlet of the third gas-liquid separator, The method further comprises feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated into a liquid hydrocarbon product and water in the single decanter.

[0007] Another aspect of the present disclosure is an apparatus coupled to an outlet of a Fischer-Tropsch reactor, comprising: A first gas-liquid separator, an inlet for receiving a product stream comprising a hydrocarbon product and water vapor; a liquid outlet for discharging a first liquid comprising a first fraction of the hydrocarbon product; a gas outlet for discharging a first gas stream comprising the remainder of the hydrocarbon product and water vapor; and a first cooler disposed between the first gas-liquid separator and the second gas-liquid separator for cooling the first gas stream to form a first cooled mixture; a second gas-liquid separator, an inlet for receiving the first cooling mixture; a liquid outlet for discharging a second liquid comprising the second fraction of the hydrocarbon product and water; a gas outlet for discharging a second gas stream comprising any remainder of the hydrocarbon product and water vapor; and a second cooler disposed between the second gas-liquid separator and the third gas-liquid separator for cooling the second gas stream to form a second cooled mixture; a third gas-liquid separator, an inlet for receiving a second cooling mixture; a liquid outlet for discharging a third fraction of the hydrocarbon product and a third liquid comprising water; a gas outlet for discharging the third gas flow; The apparatus comprises a single decanter for separating the liquid hydrocarbon product from the water, the single decanter comprising an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for the water.

[0008] Another aspect of the present disclosure is a method for producing a method for manufacturing a semiconductor device, comprising the steps of: a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products from a Fischer-Tropsch reactor and water vapor through a precooler to cool the product stream and condense a portion of the hydrocarbon products to form a cooled product stream, and thereafter feeding the cooled product stream to a first liquid-vapor separator in which the cooled product stream is separated into a first liquid comprising a first fraction of the hydrocarbon products and a first gaseous stream comprising the remainder of the hydrocarbon products and water vapor; b) collecting the first liquid at a liquid outlet of the first gas-liquid separator; c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and passing the first gas stream through a first cooler to apply cooling to the first gas stream to condense the gaseous hydrocarbon product and a portion of the water vapor to form a first cooled mixture; d) feeding the first cooled mixture from the first cooler to a second liquid / vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; e) collecting the second liquid at a liquid outlet of the second gas-liquid separator; f) discharging the second gas stream from a gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; h) feeding the second cooled mixture from the second cooler to a third liquid-vapor separator wherein the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and water, and a third gas stream; i) collecting a third liquid at a liquid outlet of the third gas-liquid separator; j) discharging a third gas stream from a gas outlet of the third gas-liquid separator, The method further comprises feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated into a liquid hydrocarbon product and water in the single decanter.

[0009] Another aspect of the present disclosure is an apparatus coupled to a Fischer-Tropsch reactor, comprising: A first gas-liquid separator, an inlet for receiving a product stream comprising a hydrocarbon product and water vapor; a liquid outlet for discharging a first liquid comprising a first fraction of the hydrocarbon product; a gas outlet for discharging a first gas stream comprising the remainder of the hydrocarbon product and water vapor; and a second gas-liquid separator, an inlet for receiving a first gas flow; a liquid outlet for discharging a second liquid comprising a second fraction of the hydrocarbon product and optionally water; a gas outlet for discharging a second gas stream comprising any remainder of the hydrocarbon product and water vapor; and a first cooler disposed between the first gas-liquid separator and the second gas-liquid separator, the first cooler cooling the first gas stream before the first gas stream reaches the second gas-liquid separator; a precooler disposed upstream of the inlet of the first liquid / gas separator for cooling the product stream before the product stream reaches the first liquid / gas separator; a third gas-liquid separator, an inlet for receiving a second gas flow; a liquid outlet for discharging a third fraction of the hydrocarbon product and a third liquid comprising water; a third gas-liquid separator including a gas outlet for discharging the third gas stream; a second cooler disposed between the second gas-liquid separator and the third gas-liquid separator, the second cooler cooling the second gas stream before the second gas stream reaches the third gas-liquid separator; The apparatus comprises a single decanter for separating the liquid hydrocarbon product from the water, the single decanter comprising an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for the water. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram of an apparatus according to the invention suitable for carrying out the method of the invention; [Diagram 2] 3 is a diagram of a further apparatus according to the invention suitable for carrying out the method of the invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] In a first aspect, the present disclosure provides a method for producing a method for a method for manufacturing a pharmaceutical composition comprising the steps of: a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products from a Fischer-Tropsch reactor and steam to a first gas-liquid separator in which the product stream is separated into a first liquid comprising a first fraction of the hydrocarbon products and a first gas stream comprising the gaseous hydrocarbon products and steam; b) collecting the first liquid at a liquid outlet of the first gas-liquid separator; c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and feeding the first gas stream through a first cooler to apply cooling to the first gas stream to condense the gaseous hydrocarbon product and a portion of the water vapor to form a first cooled mixture; d) feeding the first cooled mixture from the first cooler to a second liquid / vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; e) collecting the second liquid at a liquid outlet of the second gas-liquid separator; f) discharging the second gas stream from a gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; h) feeding the second cooled mixture from the second cooler to a third liquid-vapor separator wherein the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and water, and a third gas stream; i) collecting a third liquid at a liquid outlet of the third gas-liquid separator; j) discharging a third gas stream from a gas outlet of the third gas-liquid separator, The method further comprises feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated into a liquid hydrocarbon product and water in the single decanter.

[0012] Each aspect or embodiment defined in this specification may be combined with any other aspect(s) or embodiment(s) unless expressly indicated otherwise. In particular, any feature indicated as being preferred or advantageous may be combined with any other feature(s) indicated as being preferred or advantageous.

[0013] Advantageously, the method may allow for continuous operation. The method may beneficially reduce or substantially eliminate the accumulation of waxy product deposits in the gas-liquid separators and / or coolers, for example, by configuring the first gas-liquid separator to function as a wax trap. The method may utilize at least three gas-liquid separators and at least two coolers arranged in series. Such an arrangement may thereby avoid the need to duplicate equipment in a parallel configuration. In addition, such an arrangement may allow two or more fractions (e.g., liquid fractions) to be separated from the gas stream in a controlled and flexible manner. In particular, such an arrangement may allow multi-stage separation and cooling to be applied to the product stream. In particular, the separation of the product stream may be performed in stages, with the first stage serving to remove the waxy product from the product stream while maintaining the temperature of the product stream sufficiently high to prevent or at least substantially reduce deposition of the waxy product on the walls or components of the equipment. The staged cooling may be configured to separate the desired fractions of the hydrocarbon product at a temperature at which each fraction is maintained as a mobile liquid phase.

[0014] The term "gas-liquid separator" as used herein may encompass devices configured to separate liquid from gas. Examples of such gas-liquid separators may be referred to as knock-out pots, knock-out drums, or flash drums. Separation of liquid from gas in a gas-liquid separator may be accomplished by one or more mechanisms used alone or in combination, including, for example, gravity separation, velocity reduction, redirection (including centrifugation), and impingement on elements such as vanes, demister pads, and filter elements. A gas-liquid separator may comprise a drum (or other vessel) that may be positioned vertically or horizontally.

[0015] The term "cooler" as used herein may encompass devices configured to apply cooling to a medium, particularly a gas and / or liquid. Examples of such coolers include condensers and exchangers. The cooler may utilize, for example, one or more of gas cooling and liquid cooling. The cooling liquid may include cooling water. The cooler may be configured as a product water cooler to reduce or eliminate flash evaporation during depressurization of the liquid. The cooler may be configured as a parallel flow cooler. The cooling gas may include air. Alternatively, the gas may include a feed gas mixture for a Fischer-Tropsch reactor that generates a product stream when in use.

[0016] Advantageously, the first and second coolers can use different heat exchange media. For example, the first cooler can use the feed gas mixture for the Fischer-Tropsch reactor as its heat exchange medium, and the second cooler can use cooling water as its heat exchange medium. Advantageously, the use of a relatively high temperature heat exchange medium in the first cooler and a relatively low temperature heat exchange medium in the second cooler can allow for a gradual, stepwise cooling of the product stream. The second cooler can use a lower temperature heat exchange medium (e.g. cooling water or air) because the lighter hydrocarbons remaining by that point will remain mobile and liquid at the lower wall temperature in that part of the device since the less mobile hydrocarbons (e.g. wax product and first distillate product) have already been removed. The second cooler can advantageously be a combination of coolers in series. For example, an air-cooled heat exchanger followed by a cooling water-cooled trim heat exchanger.

[0017] The first fraction of the hydrocarbon products may comprise or consist of a wax product. The wax product may have a carbon chain length of C20 or greater. As used herein, the term "wax product" may encompass hydrocarbons having at least 20 carbon atoms. For example, the wax product may be a C20-C110 hydrocarbon, such as, for example, a C20-C40 hydrocarbon, a C20-C60 hydrocarbon, a C20-C80 hydrocarbon, or a C20-C120 hydrocarbon.

[0018] Advantageously, a first fraction of the hydrocarbon product may be separated from the gas stream before the gas stream passes through the first cooler. Advantageously, arranging for the first fraction to comprise or consist of the waxy product allows the waxy product to be separated from the gas stream at an early stage in the process while the gas stream is still at a relatively high temperature, thereby reducing or substantially eliminating the possibility of deposits of waxy hydrocarbon product plugging the apparatus, and in particular any coolers of the apparatus.

[0019] The method preferably includes feeding the second liquid from the liquid outlet of the second liquid-vapor separator to a decanter in which the second liquid is separated into the liquid hydrocarbon product and water.

[0020] The term "decanter" as used herein may encompass an apparatus configured to separate at least two liquid phases from one another, for example, a device configured to separate a hydrocarbon liquid phase from a liquid water phase. The decanter may be horizontally or vertically disposed or spherical. The decanter may have a means for discharging the gas phase.

[0021] The method may include using a sub-cooler to cool the second liquid before it reaches the decanter.

[0022] The second fraction of the hydrocarbon product may be a heavier fraction than the third fraction of the hydrocarbon product. Optionally, the second fraction of the hydrocarbon product may comprise C5 to C30 hydrocarbons and the third fraction of the hydrocarbon product may comprise C3 to C18 hydrocarbons.

[0023] The method may include feeding the third liquid from the liquid outlet of the third liquid-vapor separator to a decanter, wherein the third liquid is separated into the liquid hydrocarbon product and water.

[0024] The method includes feeding the second and third liquids to a single decanter in which the second and third liquids are separated into a liquid hydrocarbon product and water. Advantageously, this can reduce the capital costs of the equipment for carrying out the method since only a single decanter is required. A further advantage of the single decanter arrangement is that the second and third gas-liquid separators do not need to be configured as three-phase separators, which would increase their complexity and cost and require separate cooling of the liquid hydrocarbon product and water streams. In contrast, the present arrangement can use a two-phase gas-liquid separator and a single cooler to cool the combined liquid stream from the second gas-liquid separator prior to the single decanter.

[0025] The method may preferably further comprise using a sub-cooler to cool the second liquid, optionally to a temperature the same as that of the third liquid, before it reaches the single decanter.

[0026] The subcooler may advantageously use a lower temperature heat exchange medium (e.g., cooling water or air) than the upstream cooler, since the second liquid may contain lighter hydrocarbons that remain mobile and liquid at lower wall temperatures and the less mobile hydrocarbons (e.g., waxy product and first distillate product) have already been removed. The subcooler may use parallel-flow cooling with cooling water. Beneficially, this may help to avoid excessive drop in wall temperature within the subcooler itself, which may cause traces of wax carried over from the first gas-liquid separator to build up within the cooler.

[0027] The single decanter may be operated at a pressure of less than 10 bar(a), optionally less than 8 bar(a), optionally between 3 and 7 bar(a).

[0028] In some embodiments, the method may further include cooling the product stream by passing the product stream through a pre-cooler before the product stream reaches the first liquid-gas separator.

[0029] Advantageously, the use of a precooler can allow for control of the feed temperature of the product stream to the first gas-liquid separator. This can be particularly beneficial when the temperature of the incoming product stream can vary. The Fischer-Tropsch process uses a catalyst that degrades over time. Catalyst aging can require increasing the reactor temperature over time to compensate. Thus, the temperature of the product stream can vary, e.g., increase, over time within a set period of time. The use of a precooler can allow for the accommodation of variable temperature product streams. In particular, the use of a precooler can help avoid carryover of waxy product to the first cooler by providing sufficient precooling to the product stream so that the first gas-liquid separator can still function properly to remove waxy product from the product stream.

[0030] Preferably, the first and / or second cooler may be cooled by the feed gas mixture for the Fischer-Tropsch reactor.

[0031] More preferably, the product stream may be cooled in a precooler before reaching the first gas-liquid separator by heat exchange against a feed gas mixture for the Fischer-Tropsch reactor, preferably a feed gas mixture which has passed through the first cooler in heat exchange with the first gas mixture.

[0032] The temperature of the product stream exiting the reactor may be, for example, from 205 to 240°C.

[0033] The precooler, if present, may cool the product stream to a temperature in the range of 120°C to 200°C, preferably 160 to 200°C.

[0034] The product stream may be fed to the first gas-liquid separator at a temperature in the range of 120-200°C, preferably 160-200°C.

[0035] The temperature of the first cooled mixture produced in the first cooler may be, for example, 80 to 120°C.

[0036] The feed gas mixture may be heated to a temperature in the range of 100 to 220°C in the first cooler.

[0037] The feed gas mixture may be heated in the precooler (if present) to a temperature in the range of 190-220°C.

[0038] The first cooled mixture may be fed to the second gas-liquid separator at a temperature in the range of 80-120°C.

[0039] The second cooled mixture produced by the second cooler may have a temperature of, for example, 40 to 60°C.

[0040] The sub-cooler may cool the second liquid to a temperature of, for example, 40-60°C.

[0041] The second cooled mixture may be fed to a third gas-liquid separator at a temperature in the range of 40-60°C.

[0042] Advantageously, the use of a precooler and / or a first cooler and / or a second cooler and / or a subcooler may allow for a controllable and flexible temperature control of the process. In particular, the temperature of each of the gas-liquid separators may be controllable independently of one another by the coordinated use of coolers, allowing for control of the temperature and therefore the composition of each liquid fraction separated from the product stream. Advantageously, this may allow for the prevention of carryover of the waxy product to the first cooler, as well as the separation of the desired fraction of the liquid hydrocarbon product without the need for distillation.

[0043] Another aspect of the present disclosure is an apparatus coupled to an outlet of a Fischer-Tropsch reactor, comprising: A first gas-liquid separator, an inlet for receiving a product stream comprising a hydrocarbon product and water vapor; a liquid outlet for discharging a first liquid comprising a first fraction of the hydrocarbon product; a gas outlet for discharging a first gas stream comprising the remainder of the hydrocarbon product and water vapor; and a first cooler disposed between the first gas-liquid separator and the second gas-liquid separator for cooling the first gas stream to form a first cooled mixture; a second gas-liquid separator, an inlet for receiving the first cooling mixture; a liquid outlet for discharging a second liquid comprising the second fraction of the hydrocarbon product and water; a gas outlet for discharging a second gas stream comprising any remainder of the hydrocarbon product and water vapor; and a second cooler disposed between the second gas-liquid separator and the third gas-liquid separator for cooling the second gas stream to form a second cooled mixture; a third gas-liquid separator, an inlet for receiving a second cooling mixture; a liquid outlet for discharging a third fraction of the hydrocarbon product and a third liquid comprising water; a gas outlet for discharging the third gas flow; The apparatus comprises a single decanter for separating the liquid hydrocarbon product from the water, the single decanter comprising an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for the water.

[0044] The advantages and preferred features of the first aspect of the invention also apply to this aspect of the invention. The apparatus of this aspect may be used to carry out the method of the first aspect.

[0045] Advantageously, the apparatus may be operated continuously. The apparatus may be less prone to accumulation of waxy product deposits in the gas-liquid separators and / or coolers. Advantageously, the apparatus comprises at least three gas-liquid separators and at least two coolers arranged in series. Such an arrangement may thereby avoid the need to duplicate equipment in a parallel configuration. In addition, such an arrangement may allow one or more fractions (e.g., liquid fractions) to be separated from the product stream in a controlled and flexible manner. In particular, such an arrangement may allow multi-stage separation and cooling to be applied to the product stream. In particular, the separation of the product stream may be performed in stages, with a first stage serving to remove waxy products from the product stream while maintaining the temperature of the product stream sufficiently high to prevent or at least substantially reduce deposition of waxy products on the walls or components of the apparatus. The staged cooling may be configured to separate the desired fractions of the hydrocarbon product at a temperature at which each fraction is maintained as a mobile liquid phase.

[0046] The first fraction of the hydrocarbon products may comprise or consist of the waxy product.

[0047] Preferably, the decanter comprises an inlet fluidly connected to receive the second liquid from the second liquid separator, an outlet for the liquid hydrocarbon product, and an outlet for water.

[0048] Preferably, the apparatus further comprises a sub-cooler disposed between the second liquid-vapor separator and the decanter for cooling the second liquid before it reaches the decanter.

[0049] Preferably, the decanter comprises an inlet fluidly connected to receive the third liquid from the third liquid / vapor separator, an outlet for the liquid hydrocarbon product, and an outlet for water.

[0050] The apparatus includes a single decanter for separating the liquid hydrocarbon product from the water, the single decanter including an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for the water.

[0051] In some embodiments, the apparatus further comprises an auxiliary cooler disposed between the second liquid-gas separator and the single decanter for optionally cooling the second liquid to the same temperature as the third liquid before it reaches the single decanter.

[0052] In some embodiments, the apparatus further comprises a precooler positioned upstream of the inlet of the first liquid-gas separator to cool the product stream before it reaches the first liquid-gas separator.

[0053] Preferably, the precooler and the first cooler may be configured to supply a feed gas mixture for the Fischer-Tropsch reactor such that the product stream is cooled in heat exchange with the feed gas mixture after the feed gas mixture has passed through the first cooler in heat exchange with the first gas stream.

[0054] Each liquid-gas separator may be of conventional cylindrical design. Preferably, one or more of the liquid-gas separators may comprise a tapered body with an upper portion having a relatively large inner diameter for receiving the cooling mixture and a lower portion having a relatively small inner diameter for collecting the liquid, the liquid outlet of the liquid-gas separator being located in the lower portion having the relatively small inner diameter. The relative dimensions of the upper and lower portions may be sized according to their role using conventional engineering techniques. Preferably, the upper portion may have a length:diameter (L / D) ratio in the range of about 0.5-1.5:1 and the lower portion may have a length:diameter (L / D) ratio in the range of about 0.5-2.5:1, the diameter of the lower portion being smaller than the diameter of the upper portion. The diameter of the lower portion may be in the range of 30%-70% of the diameter of the upper portion. Each liquid-gas separator may have a different L / D ratio and lower portion diameter depending on their role, i.e. the amount of liquid to be separated from the vapor in the vessel. Advantageously, the tapered body and narrower lower section can reduce and / or minimize liquid residence time in the gas-liquid separator, thereby reducing or eliminating significant separation of hydrocarbon and water phases upstream of the decanter.

[0055] Another aspect of the present disclosure is a method for producing a method for manufacturing a semiconductor device, comprising the steps of: a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products from a Fischer-Tropsch reactor and water vapor through a precooler to cool the product stream and condense a portion of the hydrocarbon products to form a cooled product stream, and thereafter feeding the cooled product stream to a first liquid-vapor separator in which the cooled product stream is separated into a first liquid comprising a first fraction of the hydrocarbon products and a first gaseous stream comprising the remainder of the hydrocarbon products and water vapor; b) collecting the first liquid at a liquid outlet of the first gas-liquid separator; c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and passing the first gas stream through a first cooler to apply cooling to the first gas stream to condense the gaseous hydrocarbon product and a portion of the water vapor to form a first cooled mixture; d) feeding the first cooled mixture from the first cooler to a second liquid / vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; e) collecting the second liquid at a liquid outlet of the second gas-liquid separator; f) discharging the second gas stream from a gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; h) feeding the second cooled mixture from the second cooler to a third liquid-vapor separator wherein the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and water, and a third gas stream; i) collecting a third liquid at a liquid outlet of the third gas-liquid separator; j) discharging a third gas stream from a gas outlet of the third gas-liquid separator, The method further comprises feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated into a liquid hydrocarbon product and water in the single decanter.

[0056] The advantages and preferred features of the first aspect of the invention also apply to this aspect of the invention.

[0057] Preferably, the product stream may be cooled before reaching the first gas-liquid separator in a precooler in heat exchange with a feed gas mixture for the Fischer-Tropsch reactor which has passed through a first cooler in heat exchange with the first gas mixture.

[0058] Another aspect of the present disclosure is an apparatus comprising: A first gas-liquid separator, an inlet for receiving a first gaseous stream comprising a hydrocarbon product and water vapor; a liquid outlet for discharging a first liquid comprising a first fraction of the hydrocarbon product; a gas outlet for discharging a second gas stream comprising the remainder of the hydrocarbon product and water vapor; and a second gas-liquid separator, an inlet for receiving a second gas flow; a liquid outlet for discharging a second liquid comprising a second fraction of the hydrocarbon product and optionally water; a gas outlet for discharging a third gas stream comprising any remainder of the hydrocarbon product and water vapor; and a first cooler disposed between the first gas-liquid separator and the second gas-liquid separator for cooling the second gas stream before the second gas stream reaches the second gas-liquid separator; a precooler disposed upstream of the inlet of the first liquid / gas separator to cool the first gas stream before the first gas stream reaches the first liquid / gas separator; The apparatus comprises a single decanter for separating the liquid hydrocarbon product from the water, the single decanter comprising an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for the water.

[0059] The advantages and preferred features of the first aspect of the invention also apply to this aspect of the invention. EXAMPLES

[0060] FIG. 1 shows a diagram of a first embodiment of an apparatus according to the invention suitable for carrying out the method of the invention. The apparatus is configured to process a reaction product output from a Fischer-Tropsch reactor 1. The Fischer-Tropsch reactor 1 is configured to receive a feedstock 2 and to generate a reaction product stream by reaction of the feedstock in the presence of a catalyst. The Fischer-Tropsch reactor 1 is capable of carrying out a Fischer-Tropsch process in which a feedstock of carbon monoxide and hydrogen is reacted in the presence of a catalyst to generate a reaction product comprising hydrocarbons. The reaction product stream initially exiting the Fischer-Tropsch reactor 1 is a mixture of liquid and gaseous hydrocarbon products and water vapor. The temperature of the product stream leaving the Fischer-Tropsch reactor 1 may be, for example, between 205 and 240° C.

[0061] The apparatus comprises a first gas-liquid separator 11, a first cooler 21, a second gas-liquid separator 12, a second cooler 22 and a third gas-liquid separator 13 arranged in series. Furthermore, a single decanter 30 is provided downstream of the second and third gas-liquid separators 12, 13 in series.

[0062] The first gas-liquid separator 11 comprises an inlet 111 for receiving a product stream comprising the hydrocarbon product and water vapor output from the Fischer-Tropsch reactor 1, a liquid outlet 112 for discharging a first liquid comprising a first fraction of the hydrocarbon product, and a gas outlet 113 for discharging a first gas stream comprising the remainder of the hydrocarbon product and water vapor. The first gas-liquid separator 11 may comprise a vane pack.

[0063] The first cooler 21 is disposed between the first gas-liquid separator 11 and the second gas-liquid separator 12 and serves to cool the first gas stream by condensing the gaseous hydrocarbon products and a portion of the water vapor before the first gas stream reaches the second gas-liquid separator 12 to produce a first cooled mixture. The first cooler 21 may be configured to be fed with a feed gas mixture for the Fischer-Tropsch reactor 1 such that the first gas stream is cooled by heat exchange with the feed gas mixture.

[0064] The second gas-liquid separator includes an inlet 121 for receiving the first cooled mixture, a liquid outlet 122 for discharging a second liquid comprising a second fraction of the hydrocarbon product and optionally water, and a gas outlet 123 for discharging a second gas stream comprising any remainder of the hydrocarbon product and water vapor.

[0065] The second cooler 22 is disposed in series between the second gas-liquid separator 12 and the third gas-liquid separator 13 and serves to cool the second gas stream by condensing a portion of the gaseous hydrocarbon product and water vapor prior to reaching the third gas-liquid separator 13 to produce a second cooled mixture.

[0066] The third gas-liquid separator includes an inlet 131 for receiving the second cooled mixture, a liquid outlet 132 for discharging a third liquid comprising a third fraction of the hydrocarbon product and optionally water, and a gas outlet 133 for discharging a third gas stream comprising any remainder of the hydrocarbon product and water vapor.

[0067] Decanter 30 includes an inlet 301 fluidly connected to receive a mixed liquid feed comprising the second liquid from the second gas-liquid separator 12 and the third liquid from the third gas-liquid separator 13, an outlet 303 for the liquid hydrocarbon product, and an outlet 302 for water. A gas outlet 304 may be provided to discharge off-gas. Decanter 30 is preferably the single decanter for the apparatus.

[0068] The sub-cooler 23 is disposed in series between the second liquid-vapor separator 12 and the decanter 30 to cool the second liquid before it is mixed with the third liquid. The output from the sub-cooler 23 is mixed with the third liquid output from the third liquid-vapor separator 13 before the mixed liquid feed is provided to the decanter 30 at inlet 301.

[0069] In use, the temperature of the product stream exiting the Fischer-Tropsch reactor 1 may be, for example, 205-240°C. The method first comprises feeding the product stream (at inlet 111) to a first gas-liquid separator 11. The product stream may be fed to the first gas-liquid separator 11 at a temperature in the range of 120-240°C, preferably 160-200°C. Within the first gas-liquid separator 11, the product stream is separated into a first liquid comprising a first fraction of the hydrocarbon product and a first gas stream comprising the remainder of the hydrocarbon product and water vapor. The method also comprises collecting the first liquid at a liquid outlet 112 of the first gas-liquid separator 11. The first gas-liquid separator 11 may act as a wax trap to capture and remove waxy products from the product stream.

[0070] The method also includes discharging the first gas stream from the gas outlet 113 of the first gas-liquid separator 11 and feeding the first gas stream through a first cooler 21 to apply cooling to the first gas stream to cool the first gas stream and generate a first cooled mixture by condensing the gaseous hydrocarbon products and a portion of the water vapor. The temperature of the first cooled mixture generated in the first cooler 21 may be, for example, 80-120°C. The first cooler 21 may use a feed gas mixture for the Fischer-Tropsch reactor 1 to cool the first gas stream by heat exchange between the feed gas mixture and the first gas stream. The feed gas mixture may be heated to a temperature in the range of 100-220°C in the first cooler 21.

[0071] The method also includes feeding the first cooled mixture from the first cooler 21 to a second liquid / gas separator 12 (at inlet 121). The first cooled mixture may be fed to the second liquid / gas separator 12 at a temperature in the range of 80-120° C. Inside the second liquid / gas separator 12, the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and optionally water, and a second gas stream comprising any remainder of the hydrocarbon product and water vapor.

[0072] The method also includes collecting the second liquid at the liquid outlet 122 of the second gas-liquid separator 12. The method also includes discharging the second gas stream from the gas outlet 123 of the second gas-liquid separator 12, and feeding the second gas stream through a second cooler 22 to cool the second gas stream and produce a second cooled mixture by condensing the gaseous hydrocarbon products and a portion of the water vapor. The temperature of the second cooled mixture produced in the second cooler 22 may be, for example, 40-60°C. The second cooler 22 may use cooling water in heat exchange with the second gas stream.

[0073] The method also includes feeding the second cooled mixture from the second cooler 22 to a third gas-liquid separator 13 (at inlet 131). The second cooled mixture may be fed to the third gas-liquid separator 13 at a temperature in the range of 40-60°C. Inside the third gas-liquid separator 13, the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and optionally water, and a third gas stream comprising any remainder of the hydrocarbon product and water vapor. Further, the third liquid is collected at a liquid outlet 132 of the third gas-liquid separator 13.

[0074] The third gas stream may be relatively dry and may, for example, contain tail gas (e.g., unreacted reactants, CO, methane, ethane, etc.) which may be recycled to the Fischer-Tropsch reactor 1, or may be exhausted from the apparatus.

[0075] The method also includes feeding the second and third liquids to a decanter 30 (at inlet 301), in which the second and third liquids are separated into a liquid hydrocarbon product collected at outlet 303 and water collected at outlet 302. Furthermore, the second liquid may be passed through a subcooler 23 to cool the second liquid, preferably to the same temperature as the third liquid, before reaching the decanter 30. The subcooler 23 may cool the second liquid, for example, to a temperature of 40-60° C. The subcooler 23 may use cooling water, preferably co-current cooling water, in heat exchange with the second liquid.

[0076] Figure 2 shows a diagram of a second embodiment of an apparatus according to the invention suitable for carrying out the method of the invention. Features of the second embodiment that are the same as those of the first embodiment are given the same reference numbers in Figure 2. These features will not be described in further detail, instead reference should be made to the description of the first embodiment above.

[0077] The apparatus of the second embodiment further comprises a precooler 20. The precooler 20 is disposed in series between the Fischer-Tropsch reactor 1 and the first gas-liquid separator 11.

[0078] The precooler 20 may be configured to be supplied with a feed gas mixture for the Fischer-Tropsch reactor 1 such that the product stream from the reactor is cooled in heat exchange with the feed gas mixture. Preferably, this is after the feed gas mixture has passed through the first cooler 21 in heat exchange with the first gas stream. The feed gas mixture may be heated in the precooler 20 to a temperature in the range of 190-220°C.

[0079] In use, the method includes feeding the product stream to the first gas-liquid separator 11 (at the inlet 111) through a pre-cooler 20 so that some cooling is applied to the product stream before it reaches the first gas-liquid separator 11.

[0080] The use of the pre-cooler 20 may enable the product stream to be fed to the first gas-liquid separator 11 at a temperature in the range of 120-200°C, preferably 160-200°C, which temperature range is maintained even as the temperature of the product stream exiting the Fischer-Tropsch reactor 1 is increased to compensate for ageing of the reactor catalyst.

[0081] The remainder of the apparatus and method is as described in the first embodiment above.

[0082] It will be appreciated that the apparatus may comprise more than two gas / liquid separators, if desired, for example additional pairs of coolers and gas / liquid separators may be added in series for further processing of a fourth gas stream.

[0083] The foregoing detailed description has been provided for purposes of explanation and illustration and is not intended to limit the scope of the appended claims. Many variations of the presently preferred embodiments described herein will be apparent to those of ordinary skill in the art and remain within the scope of the appended claims and their equivalents.

Claims

1. Steps below: a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products and steam from a Fischer-Tropsch reactor to a first liquid-gas separator within which said product stream is separated into a first liquid comprising a first fraction of said hydrocarbon products and a first gas stream comprising gaseous hydrocarbon products and steam; b) collecting the first liquid at a liquid outlet of the first liquid / gas separator; c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and passing the first gas stream through a first cooler to apply cooling to the first gas stream to condense a portion of the gaseous hydrocarbon product and water vapor to form a first cooled mixture; d) feeding the first cooled mixture from the first cooler to a second liquid / vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water, and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; e) collecting the second liquid at a liquid outlet of the second liquid / gas separator; f) discharging the second gas stream from a gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; h) feeding the second cooled mixture from the second cooler to a third liquid-vapor separator wherein the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and water, and a third gas stream; i) collecting the third liquid at a liquid outlet of the third liquid / gas separator; j) discharging the third gas stream from a gas outlet of the third gas-liquid separator, the method further comprising feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated into a liquid hydrocarbon product and water.

2. 10. The process of claim 1, wherein the first fraction of the hydrocarbon product comprises or consists of a waxy product having a carbon chain length of C20 or greater.

3. 3. The process of claim 1 or claim 2, wherein the second fraction of the hydrocarbon product is a heavier fraction than the third fraction of the hydrocarbon product, and optionally, the second fraction of the hydrocarbon product comprises C5 to C30 hydrocarbons and the third fraction of the hydrocarbon product comprises C3 to C18 hydrocarbons.

4. 4. The method of any one of claims 1 to 3, further comprising using a sub-cooler to cool the second liquid, optionally to a temperature the same as that of the third liquid, before it reaches the single decanter.

5. 5. A process according to any one of claims 1 to 4, wherein the single decanter is operated at a pressure of less than 10 bar(a), optionally less than 8 bar(a), optionally between 3 and 7 bar(a).

6. 6. The method of any one of claims 1 to 5, further comprising cooling the product stream by passing the product stream through a precooler before the product stream reaches the first gas-liquid separator.

7. A process according to any one of the preceding claims, wherein the product stream is fed to the first gas-liquid separator at a temperature in the range of from 120°C to 240°C, preferably from 160 to 200°C.

8. A process according to any one of claims 1 to 7, wherein the first and / or second cooler are cooled by the feed gas mixture for the Fischer-Tropsch reactor.

9. 9. The process according to any one of claims 1 to 8, wherein the product stream is cooled in a precooler before reaching the first gas-liquid separator against a feed gas mixture for the Fischer-Tropsch reactor, preferably a feed gas mixture which has passed through the first cooler in heat exchange with the first gas mixture.

10. 10. The method of claim 9, wherein the feed gas mixture is heated in a first cooler to a temperature in the range of 100°C to 180°C.

11. 1. An apparatus coupled to the outlet of a Fischer-Tropsch reactor, comprising: A first gas-liquid separator, an inlet for receiving a product stream comprising a hydrocarbon product and water vapor; a liquid outlet for discharging a first liquid comprising a first fraction of the hydrocarbon product; a gas outlet for discharging a first gas stream comprising the remainder of the hydrocarbon product and water vapor; and a first cooler disposed between the first and second gas / liquid separators for cooling the first gas stream to form a first cooled mixture; a second gas-liquid separator, an inlet for receiving the first cooling mixture; a liquid outlet for discharging a second liquid comprising the second fraction of the hydrocarbon product and water; a gas outlet for discharging a second gas stream comprising any remainder of the hydrocarbon product and water vapor; and a second cooler disposed between the second and third gas / liquid separators for cooling the second gas stream to form a second cooled mixture; a third gas-liquid separator, an inlet for receiving the second cooling mixture; a liquid outlet for discharging a third liquid comprising a third fraction of the hydrocarbon product and water; a gas outlet for discharging the third gas flow; The apparatus comprises a single decanter for separating a liquid hydrocarbon product from water, the single decanter comprising an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for water.

12. 12. The apparatus of claim 11, wherein the first fraction of the hydrocarbon product comprises or consists of a waxy product.

13. 13. The apparatus according to claim 11 or 12, further comprising a sub-cooler disposed between the second liquid-gas separator and the single decanter for cooling the second liquid, possibly to a temperature the same as that of the third liquid, before the second liquid reaches the single decanter.

14. 14. The apparatus of any one of claims 11 to 13, further comprising a precooler positioned upstream of the inlet of the first liquid / gas separator to cool the product stream before it reaches the first liquid / gas separator.

15. 15. The apparatus of claim 14, wherein the precooler and the first cooler are configured to supply a feed gas mixture for the Fischer-Tropsch reactor such that the product stream is cooled in heat exchange with the feed gas mixture after the feed gas mixture passes through the first cooler in heat exchange with the first gas stream.

16. 16. The apparatus of any one of claims 11 to 15, wherein one or more of the liquid / gas separators comprises a tapered body with an upper portion having a relatively larger inner diameter for receiving a cooling mixture and a lower portion having a relatively smaller inner diameter for collecting liquid, the liquid outlet of the liquid / gas separator being located in the lower portion having the relatively smaller inner diameter.

17. Steps below: a) feeding a product stream comprising a mixture of liquid and gaseous hydrocarbon products and steam from a Fischer-Tropsch reactor through a precooler to cool said product stream and condense a portion of said hydrocarbon products to form a cooled product stream, and thereafter feeding said cooled product stream to a first liquid-vapor separator within which said cooled product stream is separated into a first liquid comprising a first fraction of said hydrocarbon products and a first gas stream comprising the remainder of said hydrocarbon products and steam; b) collecting the first liquid at a liquid outlet of the first liquid-gas separator; c) discharging the first gas stream from a gas outlet of the first gas-liquid separator and passing the first gas stream through a first cooler to apply cooling to the first gas stream to condense a portion of the gaseous hydrocarbon product and water vapor to form a first cooled mixture; d) feeding the first cooled mixture from the first cooler to a second liquid / vapor separator in which the first cooled mixture is separated into a second liquid comprising a second fraction of the hydrocarbon product and water, and a second gas stream comprising any remainder of the hydrocarbon product and water vapor; e) collecting the second liquid at a liquid outlet of the second liquid / gas separator; f) discharging the second gas stream from a gas outlet of the second gas-liquid separator; g) feeding the second gas stream from the gas outlet of the second gas-liquid separator through a second cooler to apply cooling to the second gas stream to condense a portion of the remainder of the hydrocarbon product and water vapor to form a second cooled mixture; h) feeding the second cooled mixture from the second cooler to a third liquid-vapor separator wherein the second cooled mixture is separated into a third liquid comprising a third fraction of the hydrocarbon product and water, and a third gas stream; i) collecting the third liquid at a liquid outlet of the third liquid / gas separator; j) discharging the third gas stream from a gas outlet of the third gas / liquid separator, The method further comprises feeding the second liquid and the third liquid to a single decanter, wherein the second liquid and the third liquid are separated into a liquid hydrocarbon product and water.

18. 18. The method of claim 17, wherein the product stream is cooled before reaching the first gas-liquid separator in the precooler in heat exchange with a feed gas mixture for the Fischer-Tropsch reactor that has passed through the first cooler in heat exchange with the first gas mixture.

19. 1. An apparatus coupled to a Fischer-Tropsch reactor, comprising: A first gas-liquid separator, an inlet for receiving a product stream comprising a hydrocarbon product and water vapor; a liquid outlet for discharging a first liquid comprising a first fraction of the hydrocarbon product; a gas outlet for discharging a first gas stream comprising the remainder of the hydrocarbon product and water vapor; and a second gas-liquid separator, an inlet for receiving the first gas flow; a liquid outlet for discharging a second liquid comprising a second fraction of the hydrocarbon product and optionally water; a gas outlet for discharging a second gas stream comprising any remainder of the hydrocarbon product and water vapor; and a first cooler disposed between the first gas-liquid separator and the second gas-liquid separator, the first cooler cooling the first gas stream before the first gas stream reaches the second gas-liquid separator; a precooler disposed upstream of the inlet of the first liquid / gas separator for cooling the product stream before it reaches the first liquid / gas separator; a third gas-liquid separator, an inlet for receiving the second gas flow; a liquid outlet for discharging a third liquid comprising a third fraction of the hydrocarbon product and water; a gas outlet for discharging the third gas stream; and a second cooler disposed between the second gas-liquid separator and the third gas-liquid separator, the second cooler cooling the second gas stream before the second gas stream reaches the third gas-liquid separator; The apparatus comprises a single decanter for separating a liquid hydrocarbon product from water, the single decanter comprising an inlet fluidly connected to receive the second and third liquids from the second and third gas-liquid separators, an outlet for the liquid hydrocarbon product, and an outlet for water.

20. 20. The apparatus of claim 19, wherein the precooler and the first cooler are configured to supply a feed gas mixture for the Fischer-Tropsch reactor such that the product stream is cooled in heat exchange with the feed gas mixture after the feed gas mixture has passed through the first cooler in heat exchange with the first gas stream.

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