Processing method of liquefied material

Abstract

The present invention provides a process for hydrotreating a liquid oil stream in continuous operation in a fixed bed reactor; wherein the liquid stream is a thermochemically decomposed oil stream and contains a polymerizable reactive compound; wherein the fixed bed reactor comprises at least a first reactor bed comprising a first hydrotreating catalyst and a second reactor bed comprising a second hydrotreating catalyst; the process comprises the steps of: (i) passing at least 50 vol.% of a flow of liquid oil through a first reactor bed and then through a second reactor bed in a first operational cycle; (ii) in a second operating cycle, upon determining that a material formed from the polymerizable reactive compound is deposited on the first reactor bed, passing a flow of liquid oil with a reduced proportion through the first reactor bed and passing a flow of liquid oil with an increased proportion through the second reactor bed and not through the first reactor bed.

Description

Technical Field

[0001] The present invention relates to the field of hydroprocessing of liquid oils such as pyrolysis oils, and more particularly to stabilizing liquid oils by hydrotreating prior to upgrading by further hydroprocessing. More particularly, the present invention relates to the stabilization of pyrolysis oils containing polymerizable reactive compounds. Background Art

[0002] The field of renewable feedstocks has been attracting considerable attention, not only in Europe but also in the United States and China. Using renewable feedstocks allows for sustainable production of hydrocarbon products within the transportation fuel range, particularly diesel, jet fuel, and naphtha, as well as petrochemicals such as raw materials for steam crackers and plastics production.

[0003] Due to the diversity and complexity of these feedstocks, the hydroprocessing of renewable feedstocks is a challenging task. Currently, it is generally believed that there are three generations of renewable feedstocks. The first generation is renewable feedstocks that are already liquid, including straight-run oils such as rapeseed oil and soybean oil. The second generation is waste oils and fats, such as waste cooking oil, animal fats and crude tall oil (CTO). The third generation is much larger in volume than the second generation, that is, it has higher availability. The third generation includes solid renewable feedstocks, including: i) solid renewable feedstocks, such as plastic waste, municipal solid waste, agricultural residues and forestry residues, such as lignocellulosic biomass (such as grass); and ii) low indirect land use change (ILUC) crops such as castor, which have the advantage of not competing with food crops for space and can grow under harsh climatic conditions.

[0004] Due to the growing focus on reducing fossil hydrocarbon feedstocks for the petrochemical industry (plastic production) and fuel production, demand for hydroprocessing of advanced renewable feedstocks, such as pyrolysis oil derived from solid renewable feedstocks, is expected to be higher. In addition, hydroprocessing is particularly beneficial for the approximately one-third of plastic waste that is not separated according to polymer type.

[0005] Pyrolysis oils and the like from waste plastics are highly unsaturated, containing olefins, dienes, conjugated dienes, aromatics, vinyl aromatics, and saturated hydrocarbons. These oils also contain heteroatoms such as nitrogen, oxygen, sulfur, and halogens. The exact properties of plastic-derived oils depend largely on the polymer composition of the feedstock to the liquefaction process. To meet the requirements for use as petrochemical feedstocks (for steam crackers), olefins must be saturated, and the number of heteroatoms must be significantly reduced. In addition, pyrolysis oils and the like from biomass may have very high oxygen contents, which need to be reduced before they can be effectively used as liquid fuels (i.e., as hydrocarbon fuels that boil in the transportation fuel range). Heteroatoms (such as nitrogen, oxygen, sulfur, and halogens) are typically removed by hydroprocessing in catalytic hydrotreating (HDT) reactors using high pressure (30-200 bar) and high temperature (320-400°C). However, liquid oils such as pyrolysis oils or hydrothermal liquefaction oils (hereinafter also referred to as HTL oils) are very unstable and easily polymerize when heated. This results in rapid deactivation of the catalyst and clogging of the catalyst bed of the HDT reactor due to coking or colloid formation. In particular, the pyrolysis oil stream typically contains polymerizable reactive compounds such as conjugated dienes, styrene homologues and oxygenated organics, which can cause fouling during various hydroprocessing steps, such as colloid formation or coking in the catalyst bed. This results in an increase in the pressure drop across the reactor bed, necessitating cleaning or replacement of the bed. Even with mild stabilization, coking of the catalyst bed may occur, leading to rapid deactivation of the hydroprocessing catalyst. In addition, when the process temperature is increased in the second step, there is a similar risk of fouling in this step because less reactive compounds may be activated.

[0006] In view of the coking of the catalyst bed and in particular the resulting high pressure drop, additional reactors are often required, either in parallel or in series with the first reactor. Figure 1 A process unit with two reactors arranged in parallel is shown, and Figure 2 A process unit with two reactors arranged in series is shown. Figure 1 and Figure 2 In a typical hydroprocessing arrangement, the high pressure drop across the reactor bed during hydroprocessing necessitates shutting down or bypassing the first reactor after a specific period of time. In this scenario, a second reactor, added in parallel or series, continues normal hydroprocessing operations. However, adding a second reactor to a process unit in this manner increases the overall capital expenditure (CAPEX) and operating expenditure (OPEX) of the process unit.

[0007] In addition, when using Figure 1 When using a parallel reactor arrangement, the catalyst volume requirement is usually doubled, which further increases the overall CAPEX and OPEX of the process unit. Figure 2When a series reactor arrangement is used, this is typically in the form of a lead-lag configuration. In this case, when the pressure drop across the lead reactor bed increases, the lead reactor is shut down for catalyst replacement or cleaning. This arrangement requires auxiliary systems including heaters, compressors, separators, and pumps, further increasing the CAPEX and OPEX of the process unit.

[0008] Therefore, it is desirable to provide a method for stabilizing liquid oil streams susceptible to polymerization, which method would result in a significant increase in CAPEX (capital expenditure) and OPEX (operating expenditure). Summary of the Invention

[0009] In one aspect, a method for hydroprocessing a liquid oil stream in a fixed bed reactor in a continuous operation is provided;

[0010] wherein the liquid oil stream is a thermochemically decomposed oil stream and contains polymerizable reactive compounds;

[0011] wherein the fixed bed reactor comprises at least a first reactor bed containing a first hydroprocessing catalyst and a second reactor bed containing a second hydroprocessing catalyst;

[0012] The method comprises the following steps:

[0013] (i) in a first operating cycle, passing at least 50 vol.% of the liquid oil stream as a first reactor bed liquid oil substream through the first reactor bed and subsequently through the second reactor bed;

[0014] (ii) in a second operation cycle, when it is determined that the material formed from the polymerizable reactive compound is deposited on the first reactor bed, passing the liquid oil stream having a reduced ratio as the first reactor bed liquid oil substream, and passing the liquid oil stream having an increased ratio that did not pass through the first reactor bed as the second reactor bed liquid oil substream through the second reactor bed,

[0015] During the second operation cycle, the volume of the first reactor bed liquid substream is at least 10 vol.% and less than 90 vol.% of the volume of the first reactor bed liquid oil substream during the first operation cycle. Detailed Description of the Invention

[0017] As described herein, in one aspect, a method for hydroprocessing a liquid oil stream in a fixed bed reactor in a continuous operation is provided;

[0018] wherein the liquid oil stream is a thermochemically decomposed oil stream and contains polymerizable reactive compounds;

[0019] wherein the fixed bed reactor comprises at least a first reactor bed containing a first hydroprocessing catalyst and a second reactor bed containing a second hydroprocessing catalyst;

[0020] The method comprises the following steps:

[0021] (i) in a first operating cycle, passing at least 50 vol.% of the liquid oil stream as a first reactor bed liquid oil substream through the first reactor bed and subsequently through the second reactor bed;

[0022] (ii) in the second operation cycle, when it is determined that the material formed of the polymerizable reactive compound is deposited on the first reactor bed, the liquid oil stream having a reduced ratio is passed as the first reactor bed liquid oil sub-stream, and the liquid oil stream having an increased ratio that has not passed through the first reactor bed is passed as the second reactor bed liquid oil sub-stream.

[0023] During the second operation cycle, the volume of the first reactor bed liquid substream is at least 10 vol.% and less than 90 vol.% of the volume of the first reactor bed liquid oil substream during the first operation cycle.

[0024] By the present invention, by converting at least the most reactive compounds in the liquid oil stream, such as furfural, furan, aldehyde, ketone and acid, into alcohols, for example, by effectively converting carbonyl compounds into alcohols and by saturating conjugated dienes and styrene homologues, stabilization of thermochemical decomposition oils, such as pyrolysis oils or hydrothermal liquefaction oils, is achieved. The present invention provides a method for such stabilization while avoiding the problems associated with catalyst bed coking caused by the reaction of polymerizable reactive compounds (such as dienes) in the liquid oil at the temperatures used. In particular, the method of the present invention provides an arrangement in which the method of the present invention can avoid intermediate reactor shutdowns by having a reactor that can be configured to bypass the first reactor bed. This in turn provides a method for hydrotreating the liquid oil stream that does not result in a significant increase in CAPEX and / or OPEX. In addition, in some cases, it may be beneficial to configure the second downstream reactor operating at a higher temperature to bypass the reactor bed in a similar manner.

[0025] The method of the present invention has one or more of the following advantages.

[0026] The volume of the hydroprocessing catalyst can be reduced, which in turn leads to a corresponding reduction in OPEX. Only one reactor is required for the hydroprocessing process over the entire catalyst cycle life. This results in an overall CAPEX savings of approximately 40%. This is comparable to a typical process unit comprising at least two reactors. Since only one reactor is required, rather than two or more reactors with significant ancillary equipment, a smaller processing unit footprint is required. Due to the smaller catalyst volume and the less steel required for the reactor and ancillary equipment, the process of the present invention has a lower carbon footprint.

[0027] Liquid oil flow

[0028] As used herein, the terms "liquid stream" and "liquid oil" refer to a feedstock that contains compounds that may react to form larger molecules at temperatures above elevated temperatures (>80°C) but below temperatures that result in substantially complete hydroprocessing, which may result in complete or partial plugging of reactors, tubes, heaters, heat exchangers, and catalysts. Examples of such mixtures can be feedstocks rich in conjugated dienes or styrene and its homologues from the thermochemical decomposition of plastic waste, municipal solid waste, refuse-derived fuels, and solid recovered fuels, feedstocks rich in carbonyl compounds and sugars from the thermochemical decomposition of lignocellulosic biomass, and nitrogen-rich feedstocks from the thermochemical decomposition of nitrogen-rich biomass (such as manure and sewage sludge), as well as similar compositions from other sources. The reactive compounds can react within the same functional group (e.g., diene with diene) or across functional groups (e.g., aldehyde with phenol).

[0029] As described herein, the process of the present invention relates to the hydroprocessing of liquid oil streams, such as thermochemical decomposition oil streams, including renewable crude oil streams or biocrude streams. In one aspect, the liquid oil stream contains at least 20 wt% oxygen (O), such as at least 30 wt% O, or at least 45 wt% O. In one aspect, the liquid oil stream contains 1 wt% to 50 wt% O, such as 5 wt% to 50 wt% O, such as 10 wt% to 50 wt% O, such as 15 wt% to 50 wt% O, such as 20 wt% to 50 wt% O, such as 25 wt% to 50 wt% O, such as 30 wt% to 50 wt% O, such as 35 wt% to 50 wt% O, such as 40 wt% to 50 wt% O, such as 45 wt% to 50 wt% O. Oxygen is suitably determined by standard elemental analysis. The oxygen content is representative of a particular reactive liquid oil feed, such as pyrolysis oil or hydrothermal liquefaction (HTL) oil, because the oxygen content can be used as an indicator of how reactive the liquid oil is. Thus, a highly reactive liquid oil stream may contain up to 45 wt% oxygen or even higher.

[0030] In one aspect, the liquid oil stream contains at least 500 ppm wt of O, e.g., 0.1 wt.% O, e.g., at least 0.5 wt.% O, e.g., at least 1 wt.%, e.g., at least 1.5 wt.% O, e.g., at least 2 wt.% O, e.g., at least 2.5 wt.% O, e.g., at least 3 wt.% O, e.g., at least 3.5 wt.% O, e.g., at least 4.5 wt.% O, e.g., at least 5 wt.% O, e.g., at least 10 wt.% O, e.g., at least 15 wt.% O, which represents a feedstock derived from the pyrolysis of a material rich in plastic waste. In one aspect, the liquid oil stream contains 0.1 wt.% to 15 wt.% O, for example, 0.5 wt.% to 15 wt.% O, for example, 1 wt.% to 15 wt.% O, for example, 2 wt.% to 15 wt.% O, for example, 3 wt.% to 15 wt.% O, for example, 4 wt.% to 15 wt.% O, for example, 5 wt.% to 15 wt.% O, for example, 6 wt.% to 15 wt.% O, for example, 7 wt.% to 15 wt.% O, for example, 8 wt.% to 15 wt.% O, for example, 9 wt.% to 15 wt.% O, for example, 10 wt.% to 15 wt.% O, for example, 11 wt.% to 15 wt.% O, for example, 12 wt.% to 15 wt.% O, for example, 13 wt.% to 15 wt.% O, for example, 14 wt.% to 15 wt.% O.

[0031] In one aspect, the thermochemical decomposition oil stream is a pyrolysis oil stream or a hydrothermal liquefaction oil (HTL oil) stream. In one aspect, the thermochemical decomposition oil stream is a pyrolysis oil stream. In one aspect, the thermochemical decomposition oil stream is a hydrothermal liquefaction oil (HTL oil) stream.

[0032] In one aspect, the thermochemical decomposition oil stream is a pyrolysis oil stream comprising at least 0.5 mol / kg of one or more of aldehyde compounds, ketones, alcohols, furfural, as measured by ASTM E3146-20.

[0033] In one aspect, the process of the invention further comprises a previous step of thermal decomposition of a solid renewable feedstock to produce said thermochemically decomposed oil stream.

[0034] As used herein, the term "thermal decomposition" should be used broadly to refer to any decomposition process in which a material is partially decomposed at elevated 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 combined liquid and gaseous streams, as well as some amount of solid char. The term should be interpreted to include processes known as pyrolysis and hydrothermal liquefaction, both in the presence and absence of catalysts.

[0035] Thus, in a particular embodiment, the thermal decomposition is pyrolysis, such as fast pyrolysis as defined below, thereby producing said pyrolysis oil stream.

[0036] It should be understood that thermal decomposition is performed in the thermal decomposition section, pyrolysis is performed in the pyrolysis section, and hydrothermal liquefaction is performed in the hydrothermal liquefaction section.

[0037] As used herein, the term "section" means a physical section comprising a unit or combination of units for performing one or more steps and / or sub-steps. 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 transport bed or a circulating fluidized bed, as is well known in the art. For example, the pyrolysis section can include a pyrolyzer unit (pyrolysis reactor), a cyclone separator for removing particulate solids such as coke, and a cooling unit for thereby producing the pyrolysis tail gas stream and the pyrolysis oil stream (i.e., condensing the pyrolysis oil). The pyrolysis tail gas stream includes light hydrocarbons, such as C1-C4 hydrocarbons, CO and CO2. The pyrolysis oil stream is also referred to as a liquid substance rich in molecular blends, including saturated and unsaturated hydrocarbons, cyclic and aliphatic hydrocarbons, and hydrocarbons containing heteroatoms such as nitrogen, oxygen, halogens and sulfur. Heteroatom-containing hydrocarbons include nitriles, amines, amides, thiols, sulfides, thiophenes, aldehydes, ketones and / or other compounds, such as furfural, having a carbonyl group, which are produced by the depolymerization of the feedstock treated in the pyrolysis.

[0038] For the purposes of the present invention, pyrolysis is preferably fast pyrolysis or slow pyrolysis. Fast pyrolysis means the thermal decomposition of solid renewable raw materials in the absence of oxygen at a temperature range of 350-650°C (e.g., about 500°C) with a reaction time of 10 seconds or less, such as 5 seconds or less, such as about 2 seconds or less. For example, fast pyrolysis can be carried out by autothermal operation, for example in a fluidized bed reactor. The latter is also known as autothermal pyrolysis and is characterized by the use of air, optionally together with an inert gas or a recycled gas, as a fluidizing gas, or by the use of a mixture of air and an inert gas or a recycled gas. Thus, partial oxidation of the pyrolysis compounds produced in the pyrolysis reactor (autothermal reactor) provides energy for the pyrolysis and improves heat transfer. For detailed information on autothermal pyrolysis, reference is made, for example, to "Heterodoxy in Fast Pyrolysis of Biomass" by Robert Brown: https: / / dx.doi.org / 10.1021 / acs.energyfuels.0c03512

[0039] "Intermediate" or "slow" pyrolysis is also suitable for feedstocks derived from waste plastics and may even be more suitable than fast pyrolysis. One reason for this is that high-nitrogen feedstocks tend to contain higher amounts of alkali metals, which increases the risk of agglomeration and defluidization. Furthermore, slow pyrolysis is currently the most common form of pyrolysis used for plastic waste and provides good oil yields.

[0040] Thus, in another embodiment, the pyrolysis step is an intermediate pyrolysis wherein the steam residence time is in the range of 10 seconds to 5 minutes, such as 11 seconds to 3 minutes. Regarding fast pyrolysis, the temperature is also in the range of 350-650° C., such as about 500° C. Typically, such pyrolysis is carried out in a pyrolysis reactor for treating different types of waste, wherein the steam is post-burned after passing through the pyrolysis reactor. Typical reactors include: Herreshoff furnaces, rotary drums, amaron, CHOREN paddle pyrolysis kilns, auger reactors, and vacuum pyrolysis reactors.

[0041] In another embodiment, the pyrolysis step is a slow pyrolysis in which the solid residence time is in the range of 5 minutes to 2 hours, for example 10 minutes to 1 hour. The temperature is suitably about 300°C. This pyrolysis produces a high char yield, which can be used as fertilizer or charcoal; pyrolysis still produces some natural gas and renewable crude oil, and if the carbon is used as fertilizer, the final bio-oil may have greenhouse gases (GHGs) greater than 100%, and is therefore carbon negative. Typical reactors are auger reactors (but the residence time is different from that of intermediate pyrolysis), fixed bed reactors, kilns, Lambiot SIFIC / CISR retorts, Lurgi processes, wagon reactors, and carbo double retorts.

[0042] It will therefore be understood that for the purposes of the present invention, the use of autothermal pyrolysis, ie, autothermal operation, is a particular embodiment for performing fast pyrolysis.

[0043] In the case of using a catalyst, there are several types of fast pyrolysis. Sometimes an acidic catalyst such as zeolite or silica-alumina catalyst is used in a pyrolysis reactor to reform the pyrolysis steam. This technology is called catalytic fast pyrolysis, which can be operated in either an in-situ mode (catalyst is located in the pyrolysis reactor) or an ex-situ mode (catalyst is placed in a separate reactor). The use of a catalyst has delivered the advantage of reducing the activation energy of the reaction, thereby significantly reducing the temperature required for pyrolysis. In addition, the selectivity of the increase in desired pyrolysis oil compounds can be achieved. In some cases, hydrogen is added to the catalytic pyrolysis, which is referred to as reactive catalytic fast pyrolysis. If the catalytic pyrolysis is carried out under high hydrogen pressure (approximately >5 barg), it is generally referred to as catalytic hydropyrolysis, and the pyrolysis product generally contains a relatively low amount of oxygen, such as 1 wt% to 5 wt%. In one aspect, the pyrolysis stage is a fast pyrolysis carried out in the absence of a catalyst and hydrogen, i.e., the fast pyrolysis stage is not catalytic fast pyrolysis, hydropyrolysis or catalytic hydropyrolysis. This has achieved a simpler and cheaper process.

[0044] In one aspect, the pyrolysis tail gas stream comprises CO, CO2 and light hydrocarbons, such as C1-C4, and optionally H2S, HCl, HCN and NH3.

[0045] In one aspect, thermal decomposition is hydrothermal liquefaction. Hydrothermal liquefaction means that by processing enough time in a hot pressurized water environment to decompose the solid biopolymer structure into main liquid components and biomass thermochemically converted into liquid fuel. Typical hydrothermal processing conditions are that the temperature is in the range of 250 DEG C-375 DEG C, and the operating pressure is in the range of 40-220bar. Compared with pyrolysis (such as fast pyrolysis), this technology provides the advantages of lower operating temperature, higher energy efficiency and lower tar yield. For detailed information about the hydrothermal liquefaction of biomass, reference is made to, for example, Golakota et al., " A review of hydrothermal liquefaction of biomass ", Renewable and Sustainable Energy Reviews, Vol. 81, Part 1, January 2018, pp. 1378-1392.

[0046] In one aspect, the pyrolysis further includes passing the solid renewable feedstock through a solid renewable feedstock preparation stage, which includes, for example, drying to remove water and / or comminution to reduce particle size. Any water / moisture in the solid renewable feedstock that evaporates in the pyrolysis stage, for example, condenses in the pyrolysis oil stream and thus proceeds in this process, which may be undesirable. Furthermore, the heat used for water evaporation absorbs heat that would otherwise be required for pyrolysis. By removing water and providing a smaller particle size in the solid renewable feedstock, the thermal efficiency of the pyrolysis stage is improved.

[0047] In one aspect, the solid renewable raw material is lignocellulosic biomass, including wood products, forestry waste, and agricultural residues. In another aspect, the solid renewable raw material is municipal waste, particularly the organic fraction thereof. For the purposes of this application, the term "municipal waste" is interchangeable with the term "municipal solid waste" and refers to raw materials containing material discarded by the public, such as mixed municipal waste with waste code 200301 in the European Waste Catalogue.

[0048] In one aspect, lignocellulosic biomass is forestry waste and / or agricultural residues and includes biomass derived from plants including grasses, such as native grasses (grasses derived from natural landscapes), wheat, e.g., wheat straw, oats, rye, reeds, bamboo, sugarcane or sugarcane derivatives, such as bagasse, corn, and other cereals.

[0049] In one aspect, the solid renewable feedstock is waste plastic.

[0050] Any combination of the above is also contemplated.

[0051] As used herein, the term "lignocellulosic biomass" refers to biomass containing cellulose, hemicellulose and optionally also lignin. The lignin or a significant portion thereof may have been removed, for example by a previous bleaching step.

[0052] As described herein, the liquid stream contains a polymerizable reactive compound. In one aspect, the polymerizable reactive compound is at least a conjugated diene. In one aspect, the polymerizable reactive compound is at least a carbonyl compound. In one aspect, the polymerizable reactive compound is at least a sugar. In one aspect, the polymerizable reactive compound is at least a styrene homolog. In one aspect, the polymerizable reactive compound is at least a vinyl-arene.

[0053] In one aspect, the liquid stream has a diene value of 1 gl / 100 g to 25 gl / 100 g, for example, 2 gl / 100 g to 25 gl / 100 g, for example, 3 gl / 100 g to 25 gl / 100 g, for example, 4 gl / 100 g to 25 gl / 100 g, for example, 5 gl / 100 g to 25 gl / 100 g, for example, 6 gl / 100 g to 25 gl / 100 g, for example, 7 gl / 100 g to 25 gl / 100 g, for example, 8 gl / 100 g to 25 gl / 100 g, for example, 9 gl / 100 g to 25 gl / 100 g, for example, 10 gl / 100 g to 25 gl / 100 g, for example, 15 gl / 100 g to 25 gl / 100 g, for example, 20 gl / 100 g to 25 gl / 100 g. In one aspect, the liquid stream has a diene value of 1 gl / 100 g to 20 gl / 100 g, for example, 1 gl / 100 g to 15 gl / 100 g, for example, 1 gl / 100 g to 10 gl / 100 g, for example, 1 gl / 100 g to 9 gl / 100 g, for example, 1 gl / 100 g to 8 gl / 100 g, for example, 1 gl / 100 g to 7 gl / 100 g, for example, 1 gl / 100 g to 6 gl / 100 g, for example, 1 gl / 100 g to 5 gl / 100 g, for example, 1 gl / 100 g to 4 gl / 100 g, for example, 1 gl / 100 g to 3 gl / 100 g, for example, 1 gl / 100 g to 2 gl / 100 g. In one aspect, the liquid stream has a diene value of at least 1 gl / 100 g, such as at least 2 gl / 100 g, such as at least 3 gl / 100 g, such as at least 4 gl / 100 g, such as at least 5 gl / 100 g, such as at least 6 gl / 100 g, such as at least 7 gl / 100 g, such as at least 8 gl / 100 g, such as at least 9 gl / 100 g, such as at least 10 gl / 100 g, such as at least 15 gl / 100 g, such as at least 20 gl / 100 g, such as at least 25 gl / 100 g. The diene value of the liquid stream can be derived using standard ASTM UOP-326.

[0054] Hydrotreating

[0055] As described herein, the process of the present invention involves hydroprocessing a liquid oil stream in a continuous operation in a fixed bed reactor comprising at least a first reactor bed containing a first hydroprocessing catalyst and a second reactor bed containing a second hydroprocessing catalyst.

[0056] The liquid oil stream hydroprocessing process of the present invention is a continuous operation. As is well known in the art, the term "continuous operation" means that during a given production cycle, the input liquid oil stream is constant, and a steady stream of liquid oil is discharged as an output product. This is in contrast to batch operations, also well known in the art, in which all the liquid oil and catalyst are introduced at the beginning of the process and the output product is discharged after a certain period of time.

[0057] In one aspect, the liquid oil is heated in a fixed bed reactor at a temperature below 400°C, such as below 390°C, such as below 380°C, such as below 370°C, such as below 360°C, such as below 350°C, such as below 340°C, such as below 330°C, such as below 320°C, such as below 310°C, such as below 300°C, such as below 290°C, such as below 280°C, such as below 270°C, such as below 260°C, such as below 250°C, such as below The hydrotreating is carried out at a temperature of 240°C, such as below 230°C, such as below 220°C, such as below 210°C, such as below 200°C, such as below 190°C, such as below 180°C, such as below 170°C, such as below 160°C, such as below 150°C, such as below 140°C, such as below 130°C, such as below 120°C, such as below 110°C, such as below 100°C, such as below 90°C, such as below 80°C, such as below 70°C.

[0058] In one aspect, the liquid oil is heated in a fixed bed reactor at 70°C to 400°C, for example, 70°C to 390°C, for example, 70°C to 380°C, for example, 70°C to 370°C, for example, 70°C to 360°C, for example, 70°C to 350°C, for example, 70°C to 340°C, for example, 70°C to 330°C, for example, 70°C to 320°C, for example, 70°C to 310°C, for example, 70°C to 300°C, for example, 70°C to 290°C, for example, 70°C to 280°C, for example, 70°C to 270°C, for example, 70°C to 260°C, for example, 70°C to 250°C, For example, the hydrotreatment is carried out at a temperature of 70°C to 240°C, for example, 70°C to 230°C, for example, 70°C to 220°C, for example, 70°C to 210°C, for example, 70°C to 200°C, for example, 70°C to 190°C, for example, 70°C to 180°C, for example, 70°C to 170°C, for example, 70°C to 160°C, for example, 70°C to 150°C, for example, 70°C to 140°C, for example, 70°C to 130°C, for example, 70°C to 120°C, for example, 70°C to 110°C, for example, 70°C to 100°C, for example, 70°C to 90°C, for example, 70°C to 80°C.

[0059] In one aspect, the liquid oil is hydrotreated in a fixed bed reactor at a temperature in the range of 70-250° C., such as in the range of 80-200° C. In one aspect, the liquid oil is hydrotreated in a fixed bed reactor at a temperature in the range of 250-400° C.

[0060] In one aspect, the temperature is in the range of 250-400°C; the pressure is 20-175 barg; and the LHSV is 0.5-8 h -1 , and the H2 / oil ratio is 5NI / L to 2000NI / L.

[0061] In one aspect, the first and second hydroprocessing catalysts convert at least one of the conjugated dienes into the corresponding monoolefins or paraffins. In one aspect, the first and second hydroprocessing catalysts convert styrene into ethylbenzene. In one aspect, the first and second hydroprocessing catalysts convert halogenated hydrocarbons into non-halogenated hydrocarbons. In one aspect, the first and second hydroprocessing catalysts convert at least one of furfural, furan, aldehyde, ketone, and acid into alcohols, and / or convert carbonyl compounds into alcohols. The alcohols can be further converted into saturated organic compounds during the stabilization process and / or in a subsequent hydroprocessing stage, such as HDO.

[0062] In one aspect, the first and second hydroprocessing catalysts are each independently selected from Mo, Ni, W, Pt, Pd, Cu, Fe, Zn and Ru based catalysts and combinations thereof. In one aspect, the catalysts are in sulfided, partially sulfided (i.e., surface passivated with sulfur), or reduced form.

[0063] In one aspect, the catalyst is a supported catalyst wherein the support is selected from alumina, silica, titania, magnesia, and combinations thereof; optionally in combination with a molecular sieve having the topology MFI, BEA, or FAU. These combinations may be in the form of physical mixtures or oxide systems such as silica-alumina, alumina-magnesia spinel, and other spinel family oxide systems.

[0064] In one aspect, the catalyst is in Ni-based, Mo-based, CoMo-based, NiMo-based, W-based, NiW-based, or Ru-based form, optionally in sulfided or reduced form.

[0065] In one aspect, the Ni-based catalyst comprises at least 90 wt.% Ni, such as at least 95 wt.%, such as at least 99 wt.%, such as 100 wt.%, based on the Group 1-12 materials in the catalyst. In one aspect, the Mo-based catalyst comprises at least 90 wt.% Mo, such as at least 95 wt.%, such as at least 99 wt.%, such as 100 wt.%, based on the Group 1-12 materials in the catalyst. In one aspect, the W-based catalyst comprises at least 90 wt.% W, such as at least 95 wt.%, such as at least 99 wt.%, such as 100 wt.%, based on the Group 1-12 materials in the catalyst. In one aspect, the Ru-based catalyst comprises at least 90 wt.% Ru, such as at least 95 wt.%, such as at least 99 wt.%, such as 100 wt.%, based on the Group 1-12 materials in the catalyst.

[0066] In one aspect, the Ni-based catalyst comprises 2-30wt% Ni in a sulfided or reduced form. In one aspect, the Mo-based catalyst comprises 2-30wt% Mo, preferably in a sulfided form. In one aspect, the CoMo-based catalyst comprises 1-10wt% Co and 2-30wt% Mo, preferably in a sulfided form. In one aspect, the NiMo-based catalyst comprises 1-10wt% Ni and 2-30wt% Mo, preferably in a sulfided form. In one aspect, the W-based catalyst comprises 2-30wt% W, preferably in a sulfided form. In one aspect, the NiW-based catalyst comprises 1-10wt% Ni and 2-30wt% W, preferably in a sulfided form. In one aspect, the Ru-based catalyst comprises 0.1-10wt% Ru, preferably in a reduced form.

[0067] In one aspect, the first and / or second hydrotreating catalyst comprises Mo. In one aspect, the first and / or second hydrotreating catalyst comprises Ni. In one aspect, the first and / or second hydrotreating catalyst comprises W. In one aspect, the first and / or second hydrotreating catalyst comprises Pt. In one aspect, the first and / or second hydrotreating catalyst comprises Pd. In one aspect, the first and / or second hydrotreating catalyst comprises Cu. In one aspect, the first and / or second hydrotreating catalyst comprises Fe. In one aspect, the first and / or second hydrotreating catalyst comprises Zn. In one aspect, the first and / or second hydrotreating catalyst comprises Ru.

[0068] In one aspect, the catalyst is sulfided. In one aspect, the hydroprocessing catalyst is a sulfided form of a Ni-Mo based catalyst, i.e., NiMoS. The catalyst can be presulfided by exposure to a sulfur-containing stream, or can be sulfided in situ during operation, for example, by sulfur present in the pyrolysis oil.

[0069] In one aspect, the Ni-Mo based catalyst is a supported catalyst having a Ni content of 3-5 wt%, a Mo content of 15-25 wt%, and optionally further having a P content of 1-3 wt%, based on the total weight of the catalyst. In one aspect, the Ni-Mo based catalyst is a supported catalyst wherein the support is selected from alumina, silica, titania, and combinations thereof; optionally in combination with a molecular sieve having a topology of MFI, BEA, or FAU.

[0070] By the present invention, it has been found that the alcohol in pyrolysis oil or hydrothermal liquefaction oil is first dehydrated to corresponding unsaturated organic compounds such as olefins, and then hydrogenated to corresponding saturated organic compounds such as alkanes.For example, the 1-octanol present in pyrolysis oil or hydrothermal liquefaction oil is first dehydrated to octenes, and then hydrogenated to octane.On the other hand, ketones such as cyclopentanone (cyclic ketone) are first hydrogenated to corresponding alcohol, i.e. cyclopentanol, and then dehydrated to cyclopentenes, and then hydrogenated to cyclopentane.The pyridine (C5H5N, i.e. the compound with organic nitrogen) present in the pyrolysis oil has suppressed dehydration, thereby showing that pyridine is adsorbed on the acidic site.Yet hydrogenation is not subject to the suppression of pyridine, therefore shows that the catalyzer according to the conditions of the present invention can be converted into alcohol by the aldehyde and ketone or other compounds with carbonyl in the pyrolysis oil that usually contain organic sulfur and nitrogen.In other words, required reaction can be realized, wherein the compound with carbonyl such as aldehyde and ketone is converted into its corresponding alcohol by hydrogenation. The alcohols can be dehydrated to the corresponding alkanes as part of the reaction that occurs during stabilization or in a subsequent hydrodeoxygenation. In addition, conjugated dienes and styrene homologues in the liquid oil can be saturated and the amount of heteroatoms reduced.

[0071] As described herein, a fixed bed reactor includes at least a first reactor bed and a second reactor bed. In one aspect, the fixed bed reactor includes a mixer positioned between the first and second reactor beds. In one aspect, the mixer is a quench mixer. The quench system, positioned between the beds, ensures proper mixing of the second reactor bed feed and the effluent from the first reactor bed, thereby avoiding flow maldistribution in the second reactor bed.

[0072] In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 80:20. In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 75:25. In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 70:30. In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 65:35. In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 60:40. In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 55:45. In one aspect, the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 50:50.

[0073] First operating cycle

[0074] As described herein, the process of the present invention includes a first operating cycle wherein at least 50 vol. % of the liquid oil stream is passed through the first reactor bed as a first reactor bed liquid oil substream and subsequently through the second reactor bed.

[0075] During a first operating cycle, at least 50 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 55 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 60 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 65 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 70 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 75 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 80 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 85 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 90 vol.% of the liquid oil flow passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 95 vol.% of the liquid oil stream passes through the first reactor bed followed by the second reactor bed. In one aspect, at least 99 vol.% of the liquid oil stream passes through the first reactor bed followed by the second reactor bed. In one aspect, 100 vol.% of the liquid oil stream passes through the first reactor bed followed by the second reactor bed.

[0076] In one aspect, in the first operating cycle, 50 vol.% to 100 vol.% of the liquid oil flow passes through the first reactor bed and then passes through the second reactor bed, for example, 55 vol.% to 100 vol.%, for example, 60 vol.% to 100 vol.%, for example, 65 vol.% to 100 vol.%, for example, 70 vol.% to 100 vol.%, for example, 75 vol.% to 100 vol.%, for example, 80 vol.% to 100 vol.%, for example, 85 vol.% to 100 vol.%, for example, 90 vol.% to 100 vol.%, for example, 95 vol.% to 100 vol.%, for example, 99 vol.% to 100 vol.%.

[0077] Second operating cycle

[0078] As described herein, the process of the present invention includes a second operating period in which, upon determining that material formed from a polymerizable reactive compound is deposited on the first reactor bed, a liquid oil stream having a reduced proportion is passed through the first reactor bed, and an increased proportion is passed through the second reactor bed and not through the first reactor bed. This stream is also referred to as the second reactor bed liquid oil substream. For the present invention, the first reactor bed liquid oil substream is maintained during this period to avoid backflow in the first reactor bed.

[0079] As described herein, during the hydroprocessing of a liquid oil stream containing polymerizable reactive compounds, the reaction of reactive compounds (e.g., dienes) can result in coking (gum formation) in the catalyst bed. This results in a pressure drop across the reactor bed, adversely affecting the hydroprocessing process and increasing the CAPEX and OPEX of the process unit. To address this issue, in the process of the present invention, when it is inferred that material has been deposited in the first reactor bed, the liquid oil stream can be at least partially diverted so as to flow through the second reactor bed.

[0080] In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 10% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 20% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 30% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 40% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 50% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 60% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 70% compared to the first operating cycle. In one aspect, the proportion of liquid oil flowing through the first reactor bed during the second operating cycle is reduced by at least 80% compared to the first operating cycle. In one aspect, the proportion of liquid oil flow through the first reactor bed is reduced by at least 90% during the second operating cycle compared to the first operating cycle.

[0081] In one aspect, in the second operating cycle, the proportion of liquid oil flow through the first reactor bed is reduced by 10% to 90%, such as 20% to 90%, such as 30% to 90%, such as 40% to 90%, such as 50% to 90%, such as 60% to 90%, such as 70% to 90%, such as 80% to 90%, compared to the first operating cycle.

[0082] In one aspect, during the second operating cycle, the proportion of liquid oil flowing through the first reactor bed decreases over time, while the proportion of liquid oil flowing through the second reactor bed but not the first reactor bed increases over time.

[0083] In one aspect, the deposition of the material formed from the polymerizable reactive compound on the first reactor bed is determined by at least one of a pressure drop, an outlet gas temperature, a reactant concentration, a product concentration, a catalyst bed temperature, a start time of the first run cycle, and combinations thereof. In one aspect, the deposition of the material formed from the polymerizable reactive compound on the first reactor bed is determined by the pressure drop. In one aspect, the deposition of the material formed from the polymerizable reactive compound on the first reactor bed is determined using a differential pressure indicator controller (PDIC).

[0084] In one aspect, determining deposition of a material formed from the polymerizable reactive compound initiates a process control signal that initiates a second run cycle.

[0085] exist Figure 3 In one aspect shown, a three-way valve located on the main feed line can be used to regulate the flow to the first and second reactor beds. Figure 4 In one aspect shown, a control valve on the feed line to the second reactor bed can be used to regulate the flow to the first and second reactor beds. Figure 3 and Figure 4 In the embodiment of the present invention, the control valve opening will be controlled by the signal of the PDIC measuring the pressure drop across the first reactor bed.

[0086] Other reactor beds and operating cycles

[0087] In one aspect, the fixed bed reactor further includes a third reactor bed containing a third hydroprocessing catalyst. In this case, the process includes a third operating period in which, when it is determined that the material formed from the polymerizable reactive compound is deposited on the second reactor bed, the liquid oil stream having a decreasing ratio passes through the first reactor bed and the second reactor bed, while the liquid oil stream having an increasing ratio passes through the third reactor bed and does not pass through the first reactor bed or the second reactor bed.

[0088] In one aspect, the fixed bed reactor includes a mixer, such as a quench mixer, located between the second and third reactor beds. A quench system installed between the beds ensures proper mixing of the third reactor bed feed and the effluent from the second reactor bed, thereby avoiding flow maldistribution in the third reactor bed.

[0089] In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 10% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 20% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 30% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 40% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 50% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 60% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and second reactor beds is reduced by at least 70% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flow through the first and second reactor beds is reduced by at least 80% compared to the first and second operating cycles. In one aspect, during the third operating cycle, the proportion of liquid oil flow through the first and second reactor beds is reduced by at least 90% compared to the first and second operating cycles.

[0090] In one aspect, in the third operating cycle, the proportion of liquid oil flow through the first and second reactor beds is reduced by 10% to 90%, such as 20% to 90%, such as 30% to 90%, such as 40% to 90%, such as 50% to 90%, such as 60% to 90%, such as 70% to 90%, such as 80% to 90%, compared to the first and second operating cycles.

[0091] In one aspect, during the third operating cycle, the proportion of liquid oil flowing through the first and / or second reactor beds decreases over time, while the proportion of liquid oil flowing through the third reactor bed but not through the first and / or second reactor beds increases over time.

[0092] In one aspect, the deposition of the material formed from the polymerizable reactive compound on the second reactor bed is determined by at least one of a pressure drop, an outlet gas temperature, a reactant concentration, a product concentration, a catalyst bed temperature, and combinations thereof. In one aspect, the deposition of the material formed from the polymerizable reactive compound on the second reactor bed is determined by the pressure drop. In one aspect, the deposition of the material formed from the polymerizable reactive compound on the second reactor bed is determined using a differential pressure indicator controller (PDIC).

[0093] The process of the present invention may include one or more other steps. These one or more other steps may be before, after or in between the steps listed herein.

[0094] In one aspect, the process further comprises passing the stabilized pyrolysis oil stream through a hydrotreating (HDT) step, which is typically operated at a higher temperature in a separate reactor. Thus, any organic heteroatoms present in the stabilized pyrolysis oil stream, such as nitrogen, sulfur, oxygen, chlorine, bromine, and fluorine, are removed, and a hydrotreated stream is produced that can be further processed to produce hydrocarbon products boiling in the transportation fuel range, such as diesel, jet fuel, and naphtha. Further processing can include any of hydrodewaxing or isomerization, which are well known in the art of petrochemical oil refining. Other types of hydrotreating, such as hydrodearomatization (HDA), are also contemplated. Catalytically active materials in hydrodearomatization typically include an active metal (typically an elemental noble metal, such as platinum and / or palladium, but may also be a sulfided base metal, such as nickel, cobalt, tungsten, and / or molybdenum) and a refractory support (such as amorphous silica-alumina, aluminum oxide, silicon dioxide, magnesium oxide, or titanium dioxide, or a combination thereof).

[0095] In one aspect, the hydrotreating (HDT) reactor is configured to operate in a first operating period and a second operating period corresponding to the fixed bed reactor, but at the same or independent standards.

[0096] BRIEF DESCRIPTION OF THE DRAWINGS

[0097] Embodiments of the present invention are explained by way of example with reference to the accompanying drawings. The drawings illustrate only examples of embodiments of the invention and therefore they are not to be considered limiting of its scope, for the invention may admit to other alternative embodiments.

[0098] Figure 1 A process unit comprising two reactors arranged in parallel is shown.

[0099] Figure 2 A process unit comprising two reactors arranged in series is shown.

[0100] Figure 3 A process unit according to the invention is shown wherein one three-way valve located in the main feed line is used to regulate the flow to each reactor bed.

[0101] Figure 4 A process unit according to the invention is shown wherein the flow to each reactor bed is regulated using one control valve in the feed line to the second reactor bed.

[0102] The invention will now be described with reference to the following non-limiting examples. Example

[0103]

[0104] In the above example, scheme A (not according to the present invention) is when two reactors are arranged in parallel, and the catalyst volume requirement is usually doubled. The first reactor is in operation, while the second reactor is loaded with hydroprocessing catalyst, is completely bypassed and is not in operation. When the pressure drop in the first reactor bed increases or the catalyst activity in the first reactor is not enough to run the process, it is usually necessary to shut down the process unit for a short time to stop the first reactor and run the second reactor. For ease of comparison, the CAPEX and OPEX under this scheme are referred to as "base". In scheme A, the higher hydroprocessing catalyst dosage, the number of reactors, the duration required to shut down the process unit, replace the reactor, and start the process unit with the second reactor means higher CAPEX and OPEX.

[0105] In scheme B (not according to the present invention), when the reactors are arranged in series (also referred to as first-after operation), the first reactor and the second reactor are operated in series, and each reactor uses half of the total catalyst volume requirement. In this case, when the pressure drop across the first reactor bed increases, the first reactor is shut down to replace or clean the catalyst. For this arrangement, auxiliary systems including heaters, compressors, separators, and pumps are required, which further increases the CAPEX and OPEX of the process unit. The process unit can continue to operate with the second reactor until the catalyst in the first reactor has been replaced. The first reactor loaded with fresh catalyst is operated as the after reactor, wherein the second reactor remains in operation as the first reactor until the pressure drop in the second reactor increases.

[0106] In Option C, a reactor is used with two or more beds, each capable of receiving fresh feed. In this embodiment, the first bed can be bypassed, while the second bed receives the bypassed feed, eliminating the need for unit shutdown or, for example, auxiliary equipment, additional catalyst, or reactors. In this embodiment, the CAPEX and OPEX savings are the highest among Options A, B, and C.

[0107] Various modifications and variations of the present invention will be apparent to those skilled in the art without departing from the scope and spirit of the present invention. Although the present invention has been described in conjunction with specific preferred embodiments, it should be understood that the claimed invention should not be unduly limited to such specific embodiments. In fact, it will be apparent to those skilled in the art of chemistry or related fields that various modifications of the described modes for carrying out the present invention are intended to fall within the scope of the following claims.

Claims

1. A method for hydrotreating a liquid oil stream in a fixed bed reactor in a continuous operation; wherein the liquid oil stream is a thermochemically decomposed oil stream and contains polymerizable reactive compounds; wherein the fixed bed reactor comprises at least a first reactor bed containing a first hydroprocessing catalyst and a second reactor bed containing a second hydroprocessing catalyst; The method comprises the following steps: (i) in a first operating cycle, passing a stream comprising at least 50 vol.% liquid oil as a first reactor bed liquid oil substream through the first reactor bed and subsequently through the second reactor bed; (ii) in a second operation cycle, when it is determined that the material formed from the polymerizable reactive compound is deposited on the first reactor bed, passing the liquid oil stream having a reduced proportion as the first reactor bed liquid oil sub-stream, and passing the liquid oil stream having an increased proportion that has not passed through the first reactor bed as the second reactor bed liquid oil sub-stream, During the second operation cycle, the volume of the first reactor bed liquid substream is at least 10 vol.% and less than 90 vol.% of the volume of the first reactor bed liquid oil substream during the first operation cycle.

2. The method of claim 1, wherein the polymerizable reactive compound is selected from the group consisting of conjugated dienes, sugars, carbonyl compounds, styrene homologues and vinyl aromatics.

3. The method according to any one of claims 1 or 2, wherein in the first operating cycle, the first reactor bed liquid oil substream comprises at least 70 vol.%, such as at least 90 vol.%, such as at least 99 vol.% of the liquid oil stream.

4. The method according to any one of claims 1 to 3, wherein in the second operating cycle, the proportion of the liquid oil stream contained in the liquid oil substream of the first reactor bed is reduced by at least 10%, such as at least 20%, such as at least 40%, such as at least 80%, compared to the first operating cycle.

5. The method according to any one of claims 1 to 4, wherein (i) in the first operating cycle, 50 vol.% to 100 vol.% of the liquid oil stream is contained in the liquid oil substream of the first reactor bed, and 0 vol.% to 50 vol.% of the liquid oil stream passes through the second reactor bed without passing through the first reactor bed; and (ii) In the second operating cycle, 25 vol.% to 75 vol.% of the liquid oil stream passes through the first reactor bed and then through the second reactor bed, and 25 vol.% to 75 vol.% of the liquid oil stream passes as the second reactor bed liquid oil substream.

6. The method according to any one of claims 1 to 5, wherein during the second operating cycle, the first reactor bed liquid oil substream decreases with time and the second reactor bed liquid oil substream increases with time.

7. The method of any one of claims 1 to 6, wherein deposition of the material formed from the polymerizable reactive compound on the first reactor bed is determined by at least one of pressure drop, outlet temperature, reactant concentration, product concentration, catalyst bed temperature, and combinations thereof.

8. The process according to any one of claims 1 to 7, wherein the fixed bed reactor comprises a mixer between the first reactor bed and the second reactor bed, for example wherein the mixer is a quench mixer.

9. The process according to any one of claims 1 to 8, wherein the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 80:20, for example, wherein the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 50:50, for example, wherein the volume ratio of the first reactor bed to the second reactor bed is from 20:80 to 40:

60.

10. The process of any one of claims 1 to 9, wherein the fixed bed reactor further comprises a third reactor bed containing a third hydrotreating catalyst; The method further comprises the following steps: (iii) in a third operation cycle, when it is determined that the material formed from the polymerizable reactive compound is deposited on the second reactor bed, the liquid oil stream having a reduced ratio is passed as the first reactor bed liquid oil sub-stream and the second reactor bed liquid oil sub-stream; and the liquid oil stream having an increased ratio is passed as the third reactor bed liquid oil sub-stream through the third reactor bed and not through the first reactor bed or the second reactor bed.

11. The process of claim 10, wherein the fixed bed reactor comprises a mixer, such as a quench mixer, located between the second reactor bed and the third reactor bed.

12. The process of any one of claims 1 to 11, wherein the first hydrotreating catalyst and the second hydrotreating catalyst are independently selected from Mo, Ni, W, Pt, Pd, Cu, Fe, Zn, and Ru-based catalysts, and combinations thereof.

13. The process of claim 12, wherein the first hydrotreating catalyst and / or the second hydrotreating catalyst is a supported Ni-Mo based catalyst having a Ni content of 3-5 wt%, a Mo content of 15-25 wt%, and optionally also a P content of 1-3 wt%, based on the total weight of the catalyst, for example wherein the support is selected from the group consisting of alumina, silica, titania, magnesia, and combinations thereof; optionally in combination with a molecular sieve having the topology MFI, BEA, or FAU, optionally wherein the Ni-Mo based catalyst is in sulfided form, i.e., NiMoS.

14. The method according to any one of claims 1 to 13, wherein the thermochemically decomposed oil stream is provided by thermal decomposition of a solid renewable raw material.

15. The method according to claim 14, wherein the thermal decomposition is: - pyrolysis, such as slow pyrolysis, fast pyrolysis and catalytic fast pyrolysis, to produce a pyrolysis oil stream; or -Hydrothermal liquefaction to produce a hydrothermal liquefied oil stream.

16. The method according to claim 14 or 15, wherein the solid renewable raw material is: - lignocellulosic biomass, including wood products, forestry waste, sewage sludge and agricultural residues; and / or - a fraction of material rich in waste plastics; and / or - municipal waste, in particular (a) its organic fraction, wherein municipal waste is defined as raw material containing materials discarded by the public, such as mixed municipal waste with waste code 200301 in the European Waste Inventory; and / or (b) a material fraction comprising at least 50 wt% plastic waste.

17. A process plant configured to carry out the method according to any one of claims 1 to 16.

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