Method and apparatus for producing hydrocarbons from liquid oil

Abstract

The present application relates to a process and an apparatus for producing a hydrocarbon product, the process comprising the steps of: i) directing a liquid oil stream to a hydroprocessing step to produce first and second 5 liquid hydrotreated streams, said hydroprocessing step comprising: i-1) optionally directing the liquid oil stream to a stabilization step in a stabilization reaction zone to produce first and second 5 liquid hydrotreated streams; to produce a stabilized flow of liquid oil; i-2) directing the liquid oil stream or optionally the stabilized liquid oil stream to a first HDO step in a hydrodeoxygenation (HDO) reaction zone to produce a first hydrotreated stream; i-3) directing 10 the first hydrotreated stream to a first separation unit to split the first hydrotreated stream into a vapor stream and the first liquid hydrotreated stream; i-4) directing the vapor stream to a second HDO step in a hydrodeoxygenation (HDO) reaction zone to produce a second hydrotreated stream; i-5) cooling the second hydrotreated stream to provide a cooled second hydrotreated stream, directing 15 the cooled second hydrotreated stream to a second separation unit, and separating therefrom at least an overhead gas stream and the second liquid hydrotreated stream; i-6) optionally, combining the first liquid hydrotreated stream with the second liquid hydrotreated stream into a primary hydrotreated stream; ii) separating the hydrocarbon product from the first or second liquid hydrotreated stream, optionally from the 20 main hydrotreated stream.

Description

[0001] The present invention relates to a method and apparatus for producing hydrocarbon products, such as jet fuel, diesel or naphtha, from a liquid oil stream, such as a pyrolysis oil stream or a hydrothermal liquefaction (HTL) oil stream.

[0002] When hydroprocessing hydrocarbon feeds containing significant amounts of oxygenates, such as pyrolysis oil and HTL oil, the resulting hydrocarbon products, particularly those from the hydrodeoxygenation (HDO) step, may still contain significant amounts of oxygenates. These residual oxygenates pose significant challenges to the HDO itself and can also hinder integration with downstream hydrogen production units (HPUs) used to generate the make-up hydrogen required for the process and equipment.

[0003] Liquid oil streams (such as pyrolysis oil and HTL oil) have an oxygen (O) content in the range of 5-50 wt% and need to have their oxygen content reduced before they can be used as hydrocarbon products (hydrocarbon fuels). For example, the oxygen content of HTL oil may be 5-10%; the oxygen content of pyrolysis oil may be as high as 50%. Oxygen is usually removed by hydroprocessing in an HDO reactor using high pressure (50-200 bar) and high temperature (350-400°C). However, liquid oil streams are very unstable and tend to polymerize when heated, resulting in rapid deactivation of the catalyst and clogging of the HDO reactor due to coking. Therefore, it is known to stabilize the liquid oil stream before the HDO step, for example, as described in the applicant's WO 2022152900.

[0004] Typically, in conjunction with the hydroprocessing of hydrocarbon feeds, the hydroprocessed stream from the HDO is sent to a hot separator or hydrogen stripper to separate the hydroprocessed stream into a vapor stream and a liquid stream. The vapor stream is further cooled, mixed with wash water, and then sent to a cold separator. From the cold separator, a sour water stream is withdrawn, along with overhead gas, which can be recycled back to the hydroprocessing process. In addition, a hydrocarbon liquid stream is withdrawn. The latter is subsequently separated into the desired hydrocarbon products, such as jet fuel, diesel, or naphtha.

[0005] For example, US 2009082603 A1 discloses a method for producing diesel-range fuels and fuel blending components from renewable feedstocks. Hydrogenation and deoxygenation are performed in one or more reactors. A vapor stream is separated from the reaction zone effluent, and carbon dioxide is separated from the vapor stream. FIG2 of this reference discloses a hydrodeoxygenation (HDO) unit 204, wherein the entire first hydrotreated stream from a first HDO zone 204a is further hydrotreated in a second HDO zone 204b. A hydrotreated effluent stream 206 is withdrawn and directed to a second HDO unit without subsequent separation of a vapor stream.

[0006] US 2013305593 A1 discloses a hydroprocessing method, wherein the separation process includes an improved enhanced hot separator system that combines a hot separator with a hot stripping column.

[0007] Applicant's WO 2021 / 180805 A1 (e.g., Figure 2 therein) discloses a method and apparatus in which a renewable feed is fed to a first catalytic hydrotreating unit (HDO) and then to a downstream high-pressure separator, such as an HP stripper. Recycled oil from the HP stripper is mixed with the renewable feed. The tail gas resulting from the final hydrocarbon separation is fed to a hydrogen production unit (HPU) to produce supplemental hydrogen.

[0008] Other prior art is disclosed in GB 2601407 and WO 2020043758 of the applicant.

[0009] Applicants have discovered that the hydrocarbon liquid stream from the cold separator still contains oxygenates, which means that carbon yield is lost to the water phase and that hydrogen cannot be produced from either the steam or liquid from the cold separator. Furthermore, the sour water withdrawn from the cold separator and the tail gas removed from the cold separator overhead also carry oxygenates.

[0010] Thus, in a general embodiment according to the first aspect of the present invention, there is provided a method for producing a hydrocarbon product, the method comprising the steps of:

[0011] i) directing the liquid oil stream to a hydroprocessing step to produce first and second liquid hydrotreated streams, the hydroprocessing step comprising:

[0012] i-1) optionally directing the liquid oil stream to a stabilization step in a stabilization reaction zone to produce a stabilized liquid oil stream;

[0013] i-2) directing the liquid oil stream or the optional stabilized liquid oil stream to a first hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a first hydrotreated stream;

[0014] i-3) directing the first hydrotreated stream to a first separation unit to split the first hydrotreated stream into a vapor stream and the first liquid hydrotreated stream;

[0015] i-4) directing the steam stream to a second hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a second hydrotreated stream;

[0016] i-5) cooling the second hydrotreated stream to provide a cooled second hydrotreated stream, directing the cooled second hydrotreated stream to a second separation unit and separating therefrom at least an overhead gas stream and the second liquid hydrotreated stream;

[0017] i-6) optionally, combining the first liquid hydroprocessing stream and the second liquid hydroprocessing stream into a main hydroprocessing stream;

[0018] ii) separating said hydrocarbon product from the first or second liquid hydroprocessed stream, optionally from said main hydroprocessed stream.

[0019] For example, the method comprises the following steps:

[0020] i) directing the liquid oil stream to a hydroprocessing step to produce a main hydrotreated stream, said hydroprocessing step comprising:

[0021] i-1) optionally directing the liquid oil stream to a stabilization step in a stabilization reaction zone to produce a stabilized liquid oil stream;

[0022] i-2) directing the liquid oil stream or the optional stabilized liquid oil stream to a first hydrodeoxygenation (HDO) step in a hydrodeoxygenation (HDO) reaction zone to produce a first hydrotreated stream;

[0023] i-3) directing the first hydrotreated stream to a first separation unit, such as a hot separator, to split the first hydrotreated stream into a vapor stream and a first liquid hydrotreated stream;

[0024] i-4) directing the steam stream to a second hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a second hydrotreated stream;

[0025] i-5) cooling the second hydrotreated stream to provide a cooled second hydrotreated stream, directing the cooled second hydrotreated stream to a second separation unit, such as a cold separator, and separating therefrom at least an overhead gas stream and a second liquid hydrotreated stream;

[0026] i-6) combining the first liquid hydroprocessed stream and the second liquid hydroprocessed stream into a main hydroprocessed stream;

[0027] ii) separating the hydrocarbon products from the main hydroprocessing stream.

[0028] The term "first aspect" or "first aspect of the invention" refers to a method according to the invention. The term "second aspect" or "second aspect of the invention" refers to an apparatus, ie a process apparatus (system), according to the invention.

[0029] The term "comprising" includes "consisting only of", ie "consisting of.

[0030] The term "reaction zone" refers to the physically defined area where a reaction occurs. For example, a reaction zone is a catalytic zone. For example, a catalytic zone is a catalytic fixed bed. For example, a reaction zone is a reactor. Thus, for example, a stabilized reaction zone is a stabilized reactor. For example, an HDO reaction zone is an HDO reactor. It is also understood that a reactor can have one or more reaction zones, such as one or more catalytic fixed beds arranged in series.

[0031] The term "stabilization reaction zone" denotes one or more stabilization reaction zones, such as one or more stabilization reactors, such as one or more stabilization reactors arranged in series.

[0032] The term "HDO reaction zone" means one or more HDO reaction zones, such as one or more HDO reactors, such as one or more HDO reactors arranged in series.

[0033] The term "hydrocarbon product" refers to one or more hydrocarbon products. Examples of hydrocarbon products are jet fuel or diesel. Examples of hydrocarbon products are naphtha.

[0034] The term "direct" means "to supply."

[0035] The term "suitably" means "optionally", ie an optional embodiment.

[0036] The term "present invention" or simply "invention" may be used interchangeably with the term "this application" or simply "application".

[0037] The HDO reaction zone in step i-2) is also referred to herein as "main HDO".

[0038] The HDO reaction zone in step i-4) is also referred to herein as "steam HDO".

[0039] The term "and / or" in connection with a given embodiment refers to any one of the three options. The term "and / or" can be used interchangeably with "at least one of" the three options.

[0040] The term "at least a portion" of a certain stream refers to the entire stream or a portion (fraction) thereof.

[0041] The article "a" or "an" is used to mean at least one.

[0042] Additional definitions are provided in conjunction with one or more embodiments below.

[0043] The present invention significantly reduces the yield loss of carbon to the aqueous phase in the second separation unit (e.g., a cold separator) in step i-5; the yield difference is 1-2 wt% of the total liquid product, making it a significant difference for an industrial process or plant producing hydrocarbons. Furthermore, as will be apparent from the embodiments below, the present invention can be integrated with a hydrogen production unit (HPU), suitably positioned downstream, to produce make-up hydrogen for the process. The gaseous hydrocarbon stream produced in the process can be fed to the HPU, further improving the carbon yield of the process and plant and enabling internal production of make-up hydrogen. Furthermore, due to the removal of oxygenates, cheaper feedstock is now available downstream of the hydrodeoxygenation (HDO) reactor (i.e., steam HDO) in step i-4). Furthermore, due to the removal of oxygenates, simulations of the process in the absence of oxygenates become significantly simpler and more robust, thereby enabling better control and operation of processes and plants based on such simulations. Furthermore, as will also be apparent from the following embodiments, the present invention makes it easier to clean acidic water generated during the process (eg in said step i-5)) in a wastewater treatment plant.

[0044] In one embodiment, the first separation unit is a hot separator and / or stripping unit, such as a high pressure stripper (HP stripper); and the second separation unit is a cold separator.

[0045] therefore:

[0046] In one embodiment, the first separation unit is a hot separator. As is well known in the art, a hot separator is a vapor-liquid separator, such as a vessel, that operates at a temperature in the range of 40-400°C, for example, 150-280°C, while maintaining the hydrocarbon components in liquid form for downstream separation into hydrocarbon products. The hot separator operates at a pressure in the range of 5-150 barg, suitably 40-120 barg. Residual oxygenates from the previous HDO step (i.e., the main HDO), such as carbonyl compounds, alcohols, or organic acids, are entrained in the vapor stream. Heat can also be supplied to product equipment (e.g., valves and piping) to prevent clogging.

[0047] In another embodiment, the first separation unit is a stripping unit, such as an HP stripper, for example a hot high-pressure stripper. As is known in the art, the term "HP stripper" refers to a high-pressure stripper in which the gaseous components of the first hydrotreated stream are stripped from the liquid components, including highly corrosive components such as HCl. The operating pressure and temperature of the high-pressure stripper are suitably the same as those of the hot separator, thus in the range of 5 to 150 barg, suitably 40 to 120 barg. Suitably, the temperature is in the range of 30 to 400°C, for example 200 to 300°C. The HP stripper can achieve separation using a stripping medium, suitably hydrogen, for example make-up hydrogen.

[0048] As is well known, the term "barg" denotes the pressure (in bars) above atmospheric pressure, which is approximately 1 bar.

[0049] In another embodiment, the first separation unit is a hot separator and an HP stripper. Thus, the first separation unit is a combination of a hot separator and an HP stripper. Because the HP stripper can be made smaller, land area and associated costs can be reduced. The cost of the hot separator and smaller HP stripper is lower than that of a separate HP stripper. The second separation unit also reduces the stripping medium requirements.

[0050] In another embodiment, the second separation unit is a cold separator, such as a high-pressure cold separator (HPCS), also known as a cold high-pressure separator (CHPS). As is well known in the art, a cold separator is a product separator in which a cooled feed, to which wash water may have been added, is supplied and the cooled feed is separated into an overhead gas stream and a liquid stream (i.e., a liquid hydroprocessing stream), and optionally also into a water stream as a by-product. The water stream is often also referred to as sour water because it may contain sulfur and nitrogen compounds, such as H2S and NH3, and, in the case of the feed according to the present invention (liquid oil), oxygen-containing compounds, such as CO2.

[0051] Suitably, a portion of the first liquid hydroprocessed stream is recycled to the main HDO reaction zone, thereby further enabling integration of the process and apparatus.

[0052] In one embodiment, the method further comprises:

[0053] - separating a portion of the overhead gas stream of step i-5) into a tail gas stream and supplying this tail gas stream to a hydrogen production unit (HPU) comprising a reforming unit to produce a supplementary hydrogen stream;

[0054] and / or

[0055] - Recycling another part of the overhead gas stream of step i-5), optionally mixed with at least a part of the make-up hydrogen stream, to any one of the following: the optional stabilization reaction zone of step i-1), the HDO reaction zone of step i-2), the HDO reaction zone of step i-4), and combinations thereof.

[0056] A highly synergistic integration is thereby achieved. The overhead gas recycle is enriched in hydrogen and light hydrocarbon compounds (e.g. methane) and may also contain HS. This is advantageous for any upstream hydroprocessing steps, as these steps require the presence of hydrogen and may also require sulfur to keep the catalyst used for stabilization and / or HDO in a sulfurized form. There is no need to obtain hydrogen and sulfur agents (e.g. dimethyl disulfide (DMDS) or the like) from external sources, as the liquid oil stream fed to the process and apparatus is suitably from a renewable source and therefore has a low sulfur content compared to fossil fuel sources. In addition, a make-up hydrogen stream is suitably generated in the HPU by supplying a small amount of side stream (i.e., the tail gas stream) generated in the process. This tail gas stream is supplied as at least part of the hydrocarbon feed to the HPU.

[0057] In a specific embodiment, the other part of the top gas stream that is recycled in step i-5) does not pass through a separation step for removing H2S and / or CO2 (optionally also removing NH3 and / or CO), and is then directed to any one of the following: the stabilization reaction zone of step i-1), the HDO reaction zone of step i-2), the HDO reaction zone of step i-4), and a combination thereof.

[0058] Thus, in one embodiment, the further portion of the overhead gas stream of step i-5) is recycled directly to any one of the following: the stabilization reaction zone of step i-1), the HDO reaction zone of step i-2), the HDO reaction zone of step i-4), and combinations thereof. It should be understood that the term "directly recycled" means that it is not treated or passed through a step (e.g., a separation step) that changes its composition other than by mixing with make-up hydrogen.

[0059] The hydrocarbon feed to the HPU may also include other hydrocarbon feed sources, such as:

[0060] -natural gas;

[0061] - naphtha produced in the process and apparatus, for example the naphtha separated as hydrocarbon product in said step ii), i.e. said hydrocarbon product being separated from the main hydroprocessing stream;

[0062] - Other light hydrocarbons produced in the process and apparatus (eg in said step ii)), such as an LPG stream (liquefied petroleum gas), ie a C3-C4 hydrocarbon stream or a fuel gas stream containing C1-C4 hydrocarbons.

[0063] Providing such hydrocarbons from an internal source rather than from an external source of natural gas significantly reduces the need for the latter as a source of hydrocarbon feed for the HPU. Reducing the amount of natural gas input can also reduce the carbon intensity, i.e., the CO2 emission factor of the process / apparatus, since the HPU uses "green" feed rather than "grey" natural gas as fuel.

[0064] Suitably, said step ii), i.e. separating said hydrocarbon products from the main hydroprocessed stream, comprises directing the main hydroprocessed stream to a product stripper to produce:

[0065] - an overhead gas fraction comprising naphtha (i.e., hydrocarbons boiling in the naphtha boiling range) and C1-C4 hydrocarbons;

[0066] - A bottoms fraction comprising any one of diesel, jet fuel, or a combination thereof as hydrocarbon product.

[0067] Suitably, step ii) further comprises a fractionation step of directing the overhead gas fraction from the product stripper further to a fractionation unit (e.g. a distillation column) to produce an overhead gas comprising said C3-C4 hydrocarbons as an LPG stream; said fuel gas stream comprising C1-C4 hydrocarbons, e.g. a C1-C2 fuel gas stream; and a bottoms stream as said naphtha.

[0068] It should be understood that the term "naphtha" refers to hydrocarbons boiling in the naphtha boiling range; the term "diesel" refers to hydrocarbons boiling in the diesel fuel boiling range; and the term "jet fuel" refers to hydrocarbons boiling in the jet fuel boiling range. These hydrocarbon products have a boiling point above 50°C.

[0069] In one embodiment, the reforming unit of the HPU is an electrically heated steam methane reformer (e-SMR). This reforming unit is particularly suitable for using small side streams, such as those described above, as a source of hydrocarbon feed for the HPU. The e-SMR is compact, thus requiring little floor space, and is powered by renewable energy sources such as wind, solar, or water (hydroelectricity). The e-SMR can also be powered by thermonuclear energy. Consequently, CO2 emissions associated with reforming the HPU are eliminated.

[0070] In another embodiment, the steam reforming unit is: a convection reformer, a tubular reformer, an autothermal reformer (ATR), an electrically heated steam methane reformer (e-SMR), or a combination thereof.

[0071] For detailed information on the HPU and the reforming unit, please refer to the applicant's WO 2021 / 180805 A1. For specific details on the e-SMR, please refer to the applicant's WO 2019 / 228797 A1.

[0072] In one embodiment, the method further comprises:

[0073] In step i-2), the optionally stabilized liquid oil stream is preheated in a fired heater to the inlet temperature of the HDO reaction zone;

[0074] In step i-4), the steam stream is preheated in a fired heater to the inlet temperature of the HDO reaction zone;

[0075] And wherein the preheating is provided in the same fired heater, ie in a common fired heater.

[0076] This enables heat integration, thereby eliminating the need for at least one fired heater, such as that associated with steam HDO. A fired heater is a unit that requires a large floor space and incurs significant capital and operating costs. A hydrocarbon fuel (e.g., natural gas) is also typically provided for combustion to generate heat in the fired heater. This results in CO2 emissions in the resulting flue gas. Therefore, eliminating the fired heater also reduces the need for hydrocarbon fuel (e.g., natural gas) and the associated CO2 emissions, as well as any other post-processing required for the flue gas generated in the fired heater.

[0077] In one embodiment, the method further comprises:

[0078] In step i-2), the optional stabilized liquid oil stream is preheated in an electric heater to the inlet temperature of the HDO reaction zone.

[0079] As is well known, an electric heater is a heating device or unit that converts electric current into heat, for example, through a resistor that provides radiant energy. Electric heaters are powered by renewable energy sources such as wind, solar, or water (hydroelectricity). Electric heaters can also be powered by thermonuclear energy. Consequently, the CO₂ emissions typically associated with heating using fired heaters are eliminated.

[0080] In one embodiment, the method comprises:

[0081] In step i-4), the steam stream is preheated to the inlet temperature of the HDO reaction zone by heat exchange with the first hydrotreated stream of step i-2); that is, the HDO inlet stream of step i-4) is preheated by heat exchange with the HDO outlet stream of step i-2).

[0082] This also enables heat integration and eliminates the need to provide fired heaters associated with steam HDO.

[0083] Suitably, the HDO reaction zones in steps i-2) (main HDO) and i-4) (steam HDO) are operated at higher temperatures and equal or lower pressures than the optional stabilization reaction zone of step i-1). Also suitably, the steam HDO is operated at a temperature equal to or lower than the main HDO.

[0084] Suitably, the stabilized reaction zone is a stabilized reactor in which the liquid oil stream is heated in the presence of a nickel-molybdenum (Ni-Mo) based catalyst at a temperature of 20-240° C., a pressure of 100-200 barg and a temperature of 0.1-1.1 h. -1 The reaction occurs with hydrogen at a liquid hourly space velocity (LHSV) of 1000 rpm. The hydrogen / liquid oil ratio is, for example, 1000-6000 NL / L, such as 2000-5000 NL / L, for example, 2500, 3000, 3500, 4000, or 4500 NL / L. The term "hydrogen / liquid oil ratio" or "H2 / oil ratio" refers to the volume ratio of the hydrogen to liquid oil flow rates. For details, please refer to the applicant's WO 2022152900.

[0085] It will be understood that the unit NL means "normal" litre, ie the amount of gas occupying that volume at 0°C and 1 atmosphere of pressure.

[0086] During the hydrotreating of liquid oils, oxygen is removed primarily as H2O, typically producing paraffinic fuels composed of paraffin waxes. This is known as the hydrodeoxygenation (HDO) pathway. Oxygen can also be removed via the decarboxylation (DCO) pathway, which produces CO2 instead of H2O:

[0087] HDO pathway:

[0088] Decarboxylation pathway:

[0089] During the stabilization of a liquid oil stream, alcohols and other acids (e.g., fatty acids) are converted: alcohols can be converted to their corresponding alkanes or unsaturated organic compounds, which are then hydrogenated to the corresponding alkanes; acids and other carbonyl-containing compounds (e.g., aldehydes and ketones) are first converted to their corresponding alcohols by hydrogenation, and then to alkanes as described above. During the stabilization process, the oxygen atom of the carbonyl group of a given organic compound can be removed as H2O or CO, following the HDO and DCO reaction pathways described above.

[0090] Following the described HDO and DCO pathways, alcohols and acids or other carbonyl-containing compounds remaining from the stabilization process will be converted into paraffins in the subsequent HDO step.

[0091] Similarly, oxygenates that were not removed in the main HDO and are now collected in the vapor stream from the first separation unit (eg, hot separator or high pressure stripper), are ultimately removed in the steam HDO.

[0092] Materials catalytically active in hydroprocessing, such as HDO, typically include an active metal (a sulfided base metal such as nickel, cobalt, tungsten, and / or molybdenum, but also elemental noble metals such as platinum and / or palladium) and a refractory support such as alumina, silica, or titania, or a combination thereof.

[0093] Hydroprocessing, referred to herein as HDO conditions, involves a temperature in the range of 250-400°C, such as 300-400°C as described, a pressure in the range of 30-250 bar, such as 50-200 bar as described, a liquid hourly space velocity (LHSV) in the range of 0.1-2, optionally with intermediate cooling by quenching with cold hydrogen, feed or product.

[0094] In one embodiment, step i-5) comprises separating a water stream from the second separation unit (e.g., a cold separator), mixing a portion of it as wash water with the second hydrotreated stream, and directing it to a cooling unit (e.g., an air cooler) to provide the cooled second hydrotreated stream, which is then introduced into the second separation unit.

[0095] Any oxygenates left in the first hydrotreated stream are carried by the steam from the first separation unit (e.g., a hot separator) and are removed before entering, for example, a cold separator. Since another portion of the water stream from the cold separator is separated as sour water, it needs to be further treated in a wastewater treatment plant. The present application can avoid the carryover of any oxygenates in the sour water, thereby making cleaning in the wastewater treatment plant easier. The presence of oxygenates in wastewater is undesirable because they are difficult to remove, resulting in high capital and operating costs associated with wastewater treatment plants. The present application also avoids the carryover of any oxygenates in the tail gas stream separated from the overhead gas stream extracted from the cold separator. Since the tail gas stream is supplied to the HPU, in particular the reforming unit therein, it is also undesirable for oxygenates to be present in the tail gas stream. The associated cleaning of the supplied hydrocarbon feed (fuel) gas, such as the requirements for a cleaning unit in the HPU upstream of the reforming unit, is significantly reduced.

[0096] For the purposes of this application, the term "oxygenate" refers to at least one of an alcohol, ether, aldehyde and ketone, carboxylic acid, and ester. Alcohols, such as methanol and ethanol, are common by-products of the hydroprocessing process and may be carried over in the hydrocarbon feed to the HPU. These alcohols may react with the catalyst in the steam methane reformer of the HPU to form undesirable products, which may reduce the efficiency of the reforming process. Ethers, such as dimethyl ether (DME) and diethyl ether (DEE), may also be present, which decompose to form alkanes and water, which can affect the steam / carbon molar ratio in the reforming. Aldehydes and ketones are also produced during the hydroprocessing process and, due to their reactivity, can cause problems, leading to undesirable side reactions in the steam reformer. Carboxylic acids may be formed during the oxidation reactions of the hydroprocessing process, causing corrosion in the steam reformer and triggering undesirable side reactions. Esters can also be formed during the hydroprocessing process and be carried over; they can decompose to form alcohols and carboxylic acids.

[0097] In one embodiment, step i-5) further comprises directing at least a portion of the overhead gas stream and / or at least a portion of the second liquid stream to a hydrodeoxygenation (HDO) step in a HDO reaction zone.

[0098] Thus, optionally, any oxygenates remaining in the vapor and / or liquid of the second separation unit, such as the cold separator, may also be removed.

[0099] In one embodiment, the liquid oil stream is a pyrolysis oil stream or a hydrothermal liquefaction oil (HTL oil) stream.

[0100] The oxygen (O) content of the pyrolysis oil stream or HTL oil stream is 5-50 wt%.

[0101] In a particular embodiment, the method comprises a prior step of thermally decomposing a solid renewable feedstock to produce said liquid oil stream, wherein the thermal decomposition step is:

[0102] - pyrolysis, such as fast pyrolysis, thereby producing said pyrolysis oil stream; or

[0103] - Hydrothermal liquefaction, thereby producing said HTL oil stream.

[0104] For convenience, the term "thermal decomposition" as used herein should be broadly applied to any decomposition process in which a material is partially decomposed at high temperatures (typically 250°C to 800°C, or even 1000°C) in the presence of substoichiometric amounts of oxygen (including in the absence of oxygen). The products are typically a combination of liquid and gas phases, as well as some amount of solid char. The term should be understood to include processes known as pyrolysis and hydrothermal liquefaction, both in the presence and absence of catalysts.

[0105] Thus, in a particular embodiment, the thermal decomposition is pyrolysis, such as fast pyrolysis, as further defined below, thereby producing said pyrolysis oil stream.

[0106] It should be understood that thermal decomposition is carried out in the thermal decomposition section. Therefore, pyrolysis is carried out in the pyrolysis section, while hydrothermal liquefaction is carried out in the hydrothermal liquefaction section.

[0107] The term "stage" refers to a physical portion comprising a unit or combination of units for performing one or more steps and / or sub-steps.

[0108] For the purposes of the present invention, the pyrolysis section produces two main streams, namely a pyrolysis tail gas stream and a pyrolysis oil stream. The pyrolysis section can be in the form of a fluidized bed, a conveying bed or a circulating fluidized bed as is well known in the art. For example, the pyrolysis section can include a pyrolysis unit (pyrolysis reactor), a cyclone separator for removing particulate solids (e.g., coke), and a cooling unit for thereby producing the pyrolysis tail gas stream and the pyrolysis oil stream (i.e., condensed pyrolysis oil). The pyrolysis tail gas stream contains light hydrocarbons (e.g., C1-C4 hydrocarbons), CO, and CO2. The pyrolysis oil stream, also known as bio-oil, is a liquid substance rich in a mixture of molecules, typically consisting of more than two hundred different compounds, including aldehydes, ketones, and / or other compounds, such as furfural having a carbonyl group, which is formed by depolymerization of the products processed in the pyrolysis.

[0109] For the purposes of the present invention, pyrolysis is preferably fast pyrolysis, also known in the art as flash pyrolysis. Fast pyrolysis refers to the thermal decomposition of solid renewable raw materials under oxygen-free conditions at a temperature of 350-650° C. (e.g., about 500° C.) with a reaction time of 10 seconds or less (e.g., 5 seconds or less, e.g., about 2 seconds). Fast pyrolysis can be performed, for example, by autothermal operation, for example, in a fluidized bed reactor. The latter is also known as autothermal pyrolysis, which is characterized by the use of air (optionally with an inert gas or recycled gas) as a fluidizing gas, or a mixture of air and an inert gas or recycled gas.

[0110] In one embodiment, thermal decomposition is hydrothermal liquefaction. Hydrothermal liquefaction refers to treating biomass in a hot pressurized water environment for a sufficiently long time to decompose the solid biopolymer structure into mainly liquid components, thereby thermochemically converting biomass into liquid fuel. Typical hydrothermal processing conditions are temperatures in the range of 250-375 ° C and operating pressures in the range of 40-220 bar. Compared with pyrolysis (such as fast pyrolysis), this technology has the advantages of lower operating temperature, higher energy efficiency and lower tar yield. For detailed information on the hydrothermal liquefaction of biomass, see, for example, Golakota et al., " A review of hydrothermal liquefaction of biomass ", Renewable and SustainableEnergy Reviews, vol.81, Part 1, Jan.2018, p.1378-1392.

[0111] In one embodiment, the pyrolysis further comprises feeding the solid renewable feedstock to a solid renewable feedstock preparation stage, which may include, for example, drying to remove water and / or pulverizing to reduce particle size. Any water / moisture in the solid renewable feedstock that evaporates, for example, in the pyrolysis stage, can condense in the pyrolysis oil stream and be carried into the process, which may be undesirable. Furthermore, the heat used to evaporate the water removes heat required for pyrolysis. By removing water and reducing the particle size of the solid renewable feedstock, the thermal efficiency of the pyrolysis stage can be improved.

[0112] In one embodiment, the solid renewable raw material is lignocellulosic biomass, including wood products, forestry waste and agricultural residues. In another embodiment, the solid renewable raw material is municipal waste, in particular the organic fraction thereof. In this article, municipal waste is defined as a raw material containing material discarded by the public, for example mixed municipal waste with the waste code 200301 in the European waste catalog. In another embodiment, the solid renewable raw material is any one of sewage sludge, waste tires, algae and plastic materials.

[0113] In a specific embodiment, the lignocellulosic biomass is forestry waste and / or agricultural residues and includes biomass derived from plants, including grasses, such as natural grasses (grasses derived from natural landscapes), wheat such as wheat straw, oats, rye, reed grass, bamboo, sugarcane or sugarcane derivatives such as bagasse, corn and other grains.

[0114] Any combination of the above is also contemplated.

[0115] As used herein, the term "lignocellulosic biomass" refers to biomass containing cellulose, hemicellulose and optionally lignin. The lignin or a substantial portion thereof may have been removed, for example by a previous bleaching step.

[0116] In a second general embodiment according to the first aspect of the present invention, there is also provided a method for producing a hydrocarbon product, the method comprising the steps of:

[0117] i) directing the liquid oil stream to a hydroprocessing step to produce first and second liquid hydrotreated streams, the hydroprocessing step comprising:

[0118] i-1) optionally directing the liquid oil stream to a stabilization step in a stabilization reaction zone to produce a stabilized liquid oil stream;

[0119] i-2) directing the liquid oil stream or the optional stabilized liquid oil stream to a first hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a first hydrotreated stream;

[0120] i-3) directing the first hydrotreated stream to a first separation unit to split the first hydrotreated stream into a vapor stream and the first liquid hydrotreated stream;

[0121] i-4) directing the steam stream to a second hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a second hydrotreated stream;

[0122] i-5) cooling the second hydrotreated stream to provide a cooled second hydrotreated stream, directing the cooled second hydrotreated stream to a second separation unit, and separating therefrom at least an overhead gas stream and the second liquid hydrotreated stream;

[0123] i-6) optionally, combining the first liquid hydroprocessing stream and the second liquid hydroprocessing stream into a main hydroprocessing stream;

[0124] ii) separating said hydrocarbon product from the first or second liquid hydroprocessed stream, optionally from said main hydroprocessed stream.

[0125] Any embodiments and associated benefits of the first general embodiment according to the first aspect of the present invention may be used with the second general embodiment according to the first aspect of the present invention, and vice versa.

[0126] The second aspect of the present invention also provides a device (system) for implementing the method of any of the above embodiments. The device comprises:

[0127] - an optional stabilization reaction zone configured to receive the liquid oil stream and provide a stabilized liquid oil stream;

[0128] a first hydrodeoxygenation (HDO) reaction zone configured to receive the liquid oil stream or optionally a stabilized liquid oil stream and provide a first hydrotreated stream;

[0129] - a first separation unit configured to receive the first hydroprocessed stream and provide: a vapor stream and a first liquid hydroprocessed stream;

[0130] a second hydrodeoxygenation (HDO) reaction zone configured to receive a steam stream and provide a second hydrotreated stream;

[0131] a cooling unit, such as an air cooler, configured to receive the second hydrotreated stream and provide a cooled second hydrotreated stream; a second separation unit configured to receive the cooled second hydrotreated stream and provide: an overhead gas stream and a second liquid hydrotreated stream;

[0132] - an optional mixing point, such as a junction, configured to combine the first liquid hydroprocessed stream with the second liquid hydroprocessed stream into a main hydroprocessed stream;

[0133] a separation section configured to receive the first or second liquid hydroprocessed stream, optionally configured to receive the main hydroprocessed stream; and to separate hydrocarbon products therefrom.

[0134] Any embodiment and associated benefits according to the first or second general embodiment of the first aspect of the invention may be used with the second aspect of the invention, and vice versa.

[0135] The sole FIGURE shows a schematic arrangement of a method and an apparatus according to an embodiment of the invention.

[0136] Referring to the accompanying drawings, there is shown a process and apparatus 10 in which a liquid oil stream 1 (suitably a pyrolysis oil stream or an HTL oil stream) is combined with an overhead recycle stream 3 to form a liquid oil stream 1', which is then preheated in a heat exchanger to provide a preheated liquid oil stream 1". The preheated stream 1" is directed to an optional stabilization reaction zone 12' (illustrated here as a stabilization reactor comprising a fixed bed of catalyst) to produce a stabilized liquid oil stream 5. The stabilized liquid oil stream 5 is cooled in a heat exchanger to provide a liquid oil stream 5', which is then directed to another optional stabilization reaction zone 12", to produce a stabilized liquid oil stream 5". This stream is then preheated in a feed / effluent heat exchanger of a main HDO reaction zone 14, using a first hydroprocessing stream 7 as a heat exchange medium, to provide a preheated stream 5'", which is further preheated in a fired heater 16' to provide a preheated and stabilized liquid oil stream 5. iv. The cooled first hydrotreated stream 7' is directed to a first separation unit 18, such as a hot separator, to split the first hydrotreated stream 7, 7' into a steam stream 9 and a first liquid hydrotreated stream 11. A portion 11' of the first liquid hydrotreated stream 11 is suitably recycled to the main HDO reaction zone 14. The steam stream 9 is preheated in a feed / effluent heat exchanger of the steam HDO reaction zone 20, using the second hydrotreated stream 13 as a heat exchange medium, thereby providing a preheated stream 9', which is further preheated in a fired heater 16" to provide a preheated steam stream 9". Instead, a common (single) fired heater 16' may be provided, for example, for preheating the feed to the main HDO reaction zone 14 and preheating the feed to the steam HDO reaction zone 20.

[0137] Thus, the second hydrotreated stream 13 is cooled to form stream 13', which is mixed with a water stream 15' provided as wash water, which is taken from the water stream 15 withdrawn from the second separation unit 22 (e.g., a cold separator). After said mixing, the second hydrotreated stream 13" is cooled in an air cooler as stream 13'" as shown and directed to the second separation unit 22. From the bottom water stream 15, a portion is also withdrawn as sour water 15", which has a low oxygenate content and is therefore further treated in a wastewater treatment plant (not shown). From the second separation unit 22, an overhead gas stream 21 is withdrawn, as is a second liquid hydrotreated stream 17. The latter is withdrawn, for example, in the form of stream 17' and combined with the first liquid hydrotreated stream 11", thereby forming a main hydrotreated stream 19. Hydrocarbon products (e.g., naphtha, diesel, and jet fuel) are then separated from the main hydrotreated stream 19 in a downstream product recovery section (not shown). It is also possible to independently separate hydrocarbons from the first liquid hydroprocessing stream 11, 11" and the second liquid hydroprocessing stream 17, 17'. For example, a portion 17" of the second liquid hydroprocessing stream 17 is directed to a separation section 24 comprising a product stripper and fractionation unit (not shown) for producing a naphtha stream, at least a portion 23 of which is provided as a source of hydrocarbon feed (hydrocarbon fuel) to a hydrogen production unit (HPU) 26. An LPG stream (not shown) may also be withdrawn in section 24 and provided to the HPU 26. A tail gas stream 21' is separated from the overhead gas stream 21 and provided as a hydrocarbon feed (fuel) to the HPU 26. A small amount of natural gas 27 may also be provided from an external source. The HPU comprises a steam reforming unit, suitably an electrically heated steam reformer (e-SMR, not shown), and produces a make-up hydrogen stream 25. Make-up hydrogen 25 is suitably mixed with another portion 21" of overhead gas stream 21 as compressed make-up hydrogen stream 25' by compressor 28'. Thus, overhead recycle stream 3 is combined with liquid oil stream 1 fed to process and apparatus 10 by recycle compressor 28". Example Existing technology:

[0138] The "baseline scenario" refers to a conventional process and apparatus without steam HDO. In the accompanying figures, this corresponds to the removal (absence) of the HDO reaction zone 20 (i.e., HDO reactor 20) and the associated heater 16" and heat exchanger. Process line (or pipe) 9 is directly connected to process line 13' and the mixing point with wash water 15' and the subsequent air cooler.

[0139] The present invention:

[0140] "With a reactor" refers to the performance of the method and apparatus as shown in the accompanying drawings and is therefore a solution according to the invention.

[0141] The following table shows the performance. Please refer to the attached figure for the relevant process pipeline (stream #):

[0142] Baseline scenario flow Feed HHPS vap CHPS vap CHPS W CHPS Liq flow# 1 9 21 15” 17 C5 and heavier components (mass) 100 8.38 0.23 1.13 7.03

[0143] With reactor flow Feed HHPS vap CHPS vap CHPS W CHPS Liq flow# 1 9 21 15” 17 C5 and heavier components (mass) 100 8.36 0.20 0.20 7.95

[0144] "HHPS vap" stands for hot high pressure separator steam. In the figures, it corresponds to the first separation unit 18 and the associated process line 9.

[0145] "CHPS vap" stands for cold high pressure separator steam. In the figure, it corresponds to the second separation unit 22 and the associated process line 21.

[0146] "CHPS W" stands for Cold High Pressure Separator Water. In the drawing, this corresponds to the second separation unit 22 and associated process line 15".

[0147] "CHPS Liq" stands for Cold High Pressure Separator Liquid. In the Figure, this corresponds to the second separation unit 22 and the associated process line 17.

[0148] "C5 and heavier (mass)" refers to the content of heavy hydrocarbons (C5+) relative to the amount of feed. This is commonly referred to in the art as wt% feed flow, or wt% FF.

[0149] In the "baseline scenario", the loss in water (CHPS W) was 1.13 wt% FF. Therefore, the yield difference was 1-2 wt% of the total liquid product.

[0150] In contrast, in the case of "with reactor" according to the invention, only 0.20 wt% FF is lost, thus saving 0.93 wt% FF.

[0151] The CHPS liquid increases by 0.92 wt% FF, which is recovered in the final liquid product. Thus, the amount of desired heavy hydrocarbons (C5+) in the final liquid product (liquid hydroprocessing stream 17) is significantly increased, for example, by more than 10%, specifically 13% ((7.95-7.03) / 7.03×100)).

[0152] Furthermore, by not sending any oxygenates to the hydrogen production unit (HPU, 26) via overhead stream 21, HPU performance and process economics are improved. Oxygenate content is harmful to the HPU's steam reformer, requiring expensive cleaning prior to introduction into the steam reformer, resulting in higher capital and operating costs. The lower oxygenate content in line 15" also makes wastewater easier to treat in a wastewater treatment facility.

Claims

1. A method for producing a hydrocarbon product, the method comprising the steps of: i) directing the liquid oil stream to a hydroprocessing step to produce first and second liquid hydrotreated streams, the hydroprocessing step comprising: i-1) optionally directing the liquid oil stream to a stabilization step in a stabilization reaction zone to produce a stabilized liquid oil stream; i-2) directing the liquid oil stream or the optional stabilized liquid oil stream to a first hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a first hydrotreated stream; i-3) directing the first hydrotreated stream to a first separation unit to split the first hydrotreated stream into a vapor stream and the first liquid hydrotreated stream; i-4) directing the steam stream to a second hydrodeoxygenation (HDO) step in a HDO reaction zone to produce a second hydrotreated stream; i-5) cooling the second hydrotreated stream to provide a cooled second hydrotreated stream, directing the cooled second hydrotreated stream to a second separation unit, and separating therefrom at least an overhead gas stream and the second liquid hydrotreated stream; i-6) optionally, combining the first liquid hydroprocessing stream and the second liquid hydroprocessing stream into a main hydroprocessing stream; ii) separating said hydrocarbon product from the first or second liquid hydroprocessed stream, optionally from said main hydroprocessed stream.

2. The process according to claim 1, wherein the first separation unit is a hot separator and / or a stripping unit, such as a high-pressure stripper; and the second separation unit is a cold separator.

3. The method according to any one of claims 1 to 2, further comprising: - separating a portion of the overhead gas stream of step i-5) into a tail gas stream and supplying this tail gas stream to a hydrogen production unit (HPU) comprising a reforming unit to produce a supplementary hydrogen stream; and / or - Recycling another part of the overhead gas stream of step i-5), optionally mixed with at least a part of the make-up hydrogen stream, to any one of the following: the optional stabilization reaction zone of step i-1), the HDO reaction zone of step i-2), the HDO reaction zone of step i-4), and combinations thereof.

4. The process of claim 3, wherein the further portion of the overhead gas stream of step i-5), optionally mixed with at least a portion of the make-up hydrogen stream, is recycled directly to any one of the optional stabilization reaction zone of step i-1), the HDO reaction zone of step i-2), the HDO reaction zone of step i-4), and combinations thereof.

5. The method according to any one of claims 3-4, wherein the reforming unit of the HPU is an electrically heated steam methane reformer (e-SMR).

6. The method according to any one of claims 1 to 5, further comprising: In step i-2), the optionally stabilized liquid oil stream is preheated in a fired heater to the inlet temperature of the HDO reaction zone; In step i-4), the steam stream is preheated in a fired heater to the inlet temperature of the HDO reaction zone; wherein the preheating is provided in the same fired heater.

7. The method according to any one of claims 1 to 5, further comprising: In step i-2), the optionally stabilized liquid oil stream is preheated in an electric heater to the inlet temperature of the HDO reaction zone; and / or In step i-4), the steam stream is preheated to the inlet temperature of the HDO reaction zone by heat exchange with the first hydrotreated stream of step i-2).

8. The process according to any one of claims 1 to 7, wherein step i-5) comprises separating a water stream from the second separation unit, mixing a portion thereof as wash water with the second hydrotreated stream, and directing it to a cooling unit to provide the cooled second hydrotreated stream, and then introducing the cooled second hydrotreated stream into the second separation unit.

9. The process according to any one of claims 1 to 8, wherein step i-5) further comprises directing at least a portion of the overhead gas stream and / or at least a portion of the second liquid hydrotreated stream to a hydrodeoxygenation (HDO) step in a HDO reaction zone.

10. The method of any one of claims 1 to 9, wherein the liquid oil stream is a pyrolysis oil stream or a hydrothermal liquefaction oil (HTL oil) stream.

11. The method of claim 10, further comprising a prior step of thermally decomposing a solid renewable feedstock to produce the liquid oil stream, wherein the thermal decomposition step is: - pyrolysis, such as fast pyrolysis, thereby producing said pyrolysis oil stream; or - Hydrothermal liquefaction, thereby producing said HTL oil stream.

12. An apparatus (10) for implementing the method according to any one of claims 1 to 11, comprising: - an optional stabilization reaction zone (12', 12") configured to receive the liquid oil stream (1, 1', 1") and provide a stabilized liquid oil stream (5, 5', 5", 5 IV ); - a first hydrodeoxygenation (HDO) reaction zone (14) configured to receive a liquid oil stream (1, 1', 1") or an optional stabilized liquid oil stream (5, 5', 5", 5" IV ), and providing a first hydrotreated stream (7, 7'); a first separation unit (18) configured to receive the first hydrotreated stream (7, 7') and provide: a vapor stream (9, 9', 9") and a first liquid hydrotreated stream (11, 11', 11"); a second hydrodeoxygenation (HDO) reaction zone (20) configured to receive the steam stream (9, 9', 9") and provide a second hydrotreated stream (13, 13'); a cooling unit configured to receive the second hydrotreated stream (13, 13', 13") and provide a cooled second hydrotreated stream (13"); a second separation unit (22) configured to receive the cooled second hydrotreated stream (13") and provide: an overhead gas stream (21) and a second liquid hydrotreated stream (17, 17', 17"); - an optional mixing point, such as a junction, configured to combine the first liquid hydroprocessed stream (11") with the second liquid hydroprocessed stream (17') into a main hydroprocessed stream (19); A separation section configured to receive the first or second liquid hydroprocessing stream (11', 17', 17', 17"), optionally configured to receive the main hydroprocessing stream (19); and to separate hydrocarbon products therefrom.

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