INSTALLATION AND PROCESS OF HYDROTREADING OR HYDROCOVERY WITH TUBULAR HEAT EXCHANGERS EQUIPPED WITH INSERTS

Abstract

The present invention relates to a hydrotreatment or hydroconversion installation and process employing at least one tubular feed-effluent heat exchanger equipped with inserts. Figure 1 to be published

Description

Title of the invention: INSTALLATION AND METHOD FOR HYDROTHERAPY OR HYDROCOVERY WITH TUBULAR HEAT EXCHANGERS EQUIPPED WITH INSERTS technical field

[0001] The present invention relates to the field of hydrotreating (e.g. hydrodemetallation, hydrodeazotation and / or hydrodesulfurization of residue or diesel fuel) and hydroconversion (e.g., hydrocracking of heavy feedstocks). In particular, the present invention relates to the use of inserts in tubular heat exchangers implemented in hydrotreating or hydroconversion units. Prior art

[0002] The use of heat exchangers in units for the hydrotreating or hydroconversion of petroleum feedstocks is known, particularly for preheating the feedstock mixed with hydrogen before it is sent to a hydrotreating or hydroconversion reactor. The heat exchange is conventionally carried out in the heat exchanger between the feedstock and the hydrotreated / hydroconverted effluent exiting the reactor; such a heat exchanger is commonly referred to in the field as a "feed-effluent" heat exchanger.

[0003] In general, a furnace placed downstream of the feed-effluent exchanger, before the entry into the reactor, makes it possible to bring the feed to the target temperature of the reactor required for carrying out the hydrotreatment and / or hydroconversion reactions.

[0004] Patents FR3075941 and FR3075942 refer to such hydrotreatment or hydroconversion processes in which feed-effluent heat exchangers are used, and in particular relate to particular feed-effluent heat exchangers, known as wound heat exchangers, comprising several bundles of tubes wound helically around a central core, in many superimposed layers, which provide gains in efficiency and operating costs compared to conventional shell-and-tube heat exchangers, but which nevertheless constitute complex and expensive equipment to manufacture.

[0005] Conventional shell-and-tube heat exchangers have been known for a long time. US patents 2978226, EPI 113238, and EP 2975353 describe examples of this type of heat exchanger. Well-known shell-and-tube heat exchangers include, for example, BEU or DEU standard heat exchangers. which include U-shaped heat exchanger tube bundles (known as "U-tube bundles" in English). Other examples of shell-and-tube heat exchangers are known in the oil refining industry, such as AES tubular heat exchangers with tubes in which the fluid passes in a single pass.

[0006] Tubular heat exchangers (i.e., comprising tubes, for example, shell-and-tube heat exchangers) of the feed-effluent type used in hydrotreatment or hydroconversion processes are characterized by being two-phase heat exchangers, meaning that the fluid on the tube side comprises two phases, typically liquid and gas. Any increase in pressure drop is often critical for the operation of this type of heat exchanger, compared to single-phase heat exchangers (i.e., the fluid on the tube side comprises only one phase, typically liquid).Not only are pressure losses generally higher in two-phase heat exchangers compared to single-phase ones, but these feed-to-effluent heat exchangers in hydrotreatment and / or hydroconversion processes operate at high pressure, and the hydrogen compressor(s) used in these processes are expensive pieces of equipment designed to operate at a specific target pressure drop that the feed-to-effluent heat exchanger must maintain. The variation around this target pressure drop value, particularly the excess pressure drop (also called additional pressure drop or extra pressure drop), must be minimal, typically less than 10 mbar / m (1.0 x 10⁴ MPa / m) or even less. The pressure drop constraint is therefore particularly critical for tubular heat exchangers of the charge-effluent type used in hydrotreatment or hydroconversion processes.

[0007] Furthermore, it is generally known to use heat exchanger insert technologies to improve heat transfer efficiency and reduce fouling of industrial heat exchanger tubes. These inserts can be static or moving, typically rotating, within the tubes, can have different shapes, for example, comprising a winding of rigid metal wire, a twisted band, or a central shaft with blades, and can be attached to the tube in different ways, for example, on one end or on both ends of the tube.

[0008] Fouling due to deposits in heat exchangers can affect many fields, such as oil refining, petrochemicals or other fields of chemistry, food processing or energy. These deposits can originate from impurities present in liquid streams from various processes, and / or from the decomposition or formation of products Organic compounds such as polymers or hydrocarbons, and mineral products, are present in these liquid streams. These can include suspended impurities that accumulate, deposits of dissolved mineral salts, coke formation, or sulfur compounds soluble in hydrocarbon streams. These deposits can be generated by excessive fluid temperatures or result from corrosion. These deposits, which gradually accumulate on the walls of heat exchanger tubes over time, impair the performance of the heat exchangers, causing them to lose efficiency over time. The deposits form a solid substance with low thermal conductivity, which insulates the walls and reduces heat transfer within the exchanger, ultimately harming the energy efficiency of the industrial processing or manufacturing unit using the heat exchanger. Another consequence of the formation of these deposits on the internal walls of heat exchanger tubes can be reduced flow rates, which are detrimental to the proper functioning of the downstream process, and / or hot spots on the tube's internal surface. These restrictions and / or hot spots can lead to deterioration of the tube structure and thus cause product leaks that can be hazardous to the operator and / or equipment. Fouling of the tubes in a feed-to-effluent heat exchanger can also lead to increased fuel consumption in the furnace located downstream of the heat exchanger in hydrotreating or hydroconversion units for hydrocarbon feedstocks.

[0009] In the field of oil refining in particular, there are many units using heat exchangers that are susceptible to fouling. One example is the refining of crude oil, which involves preheating the crude oil with the hot atmospheric residue exiting an atmospheric distillation unit. Many so-called heavy crude oils are very rich in asphaltenic compounds that can form sediments, as well as in sulfur and other corrosive compounds that are prone to depositing on the internal walls of the heat exchanger tubes through which they circulate.

[0010] The integration of inserts into heat exchanger tubes during the preheating of crude oil to improve heat exchange and reduce fouling is thus known, and for example described in patent FR2569829, which relates to a rotary-type insert comprising a rigid solenoid-shaped metal winding that is rotated by the fluid circulating in the tube. However, since this involves preheating crude oil that is subsequently sent to an atmospheric distillation unit, the pressure conditions (atmospheric pressure) do not constitute a constraint for the heat exchangers used for preheating, which are in in addition to single-phase heat exchangers, which are also less constrained in terms of pressure loss.

[0011] Another problem frequently encountered in the field of hydrotreating or hydroconversion is related to catalyst deactivation and the strategies implemented to optimize catalyst use in the process. Indeed, in hydrotreating or hydroconversion processes, a catalyst is typically used that deactivates over time, notably due to catalyst poisoning by metals contained in the feedstock or by coke forming in the reactors. To counteract this catalyst deactivation, an increase in reactor temperature is generally implemented during the lifetime of the hydrotreating / hydroconversion unit in order to maintain process performance.This allows, in particular, for an increase in cycle time related to the lifespan of the catalyst in the reactor, and thus limits the frequency of replacing the spent catalyst with fresh catalyst and / or the quantity of fresh catalyst used as top-up, and the associated costs. However, in some cases, it can be difficult to achieve the desired temperature levels due to the technical limitations of the equipment used to heat the feed, such as furnaces and heat exchangers.

[0012] Another problem faced by manufacturers is that hydrotreating or hydroconversion units must be able to treat loads that may vary over time, and in particular loads that may have a different fouling power.

[0013] In general, the refining and petrochemical industries are increasingly actively seeking solutions to reduce their energy bills and CO2 emissions. Improving the energy efficiency of heat exchangers is a promising avenue for achieving these objectives.

[0014] The present invention falls within this context and relates to the use of inserts in feed-effluent type tube heat exchangers for hydrotreatment and / or hydroconversion processes of hydrocarbon feedstocks. Objectives and Summary of the Invention

[0015] The present invention aims to overcome, at least in part, the prior art problems described above, and in particular aims to provide a hydrotreatment and / or hydroconversion plant for hydrocarbon feedstocks incorporating at least one tubular feed / effluent heat exchanger, and the associated process, meeting one or more of the following objectives: - reduce CO2 emissions from the process, in particular from a hydrotreating process of middle distillates (diesel) which follows a so-called "cold" scheme as defined later in the description; - increase the processing capacity of the installation / process; - lower capital expenditure (CAPEX) on heat exchangers with the possibility of using smaller heat exchangers for a given treatment capacity of the installation / process; - to provide flexibility in the operation of the installation and the process in case of variation in the load being processed, particularly in terms of fouling power.

[0016] Thus, to achieve at least one of the aforementioned objectives, among others, the present invention proposes, according to a first aspect, a hydroconversion or hydrotreatment installation for a hydrocarbon feedstock, comprising: - at least one tubular feed-effluent heat exchanger configured to: preheat and directly send the hydrocarbon feed mixed with a hydrogen stream to a feed furnace of a hydrotreating or hydroconversion reaction section, and to cool a reaction effluent from the reaction section of hydrotreatment or hydroconversion, said tubular charge-effluent heat exchanger comprising a plurality of tubes through which the reaction effluent passes, said tubes comprising an insert; - the charging furnace configured to heat and send the preheated hydrocarbon feed-hydrogen stream mixture to the hydrotreating or hydroconversion reaction section; - the hydrotreating or hydroconversion reaction section configured to hydrotreat or hydroconvert the hydrocarbon feedstock and produce the reaction effluent; - a first air-cooled condenser configured to cool at least part of the reaction effluent cooled by said tubular charge-effluent heat exchanger before it is sent into a high-pressure cold separator vessel; - the high-pressure cold separator vessel configured to separate at least a portion of the cooled reaction effluent into a first liquid effluent comprising at least a light fraction and a first gaseous effluent comprising hydrogen, and - a separation column configured to separate said first liquid effluent comprising at least a light fraction into a bottom liquid and a top effluent.

[0017] According to one or more embodiments of the invention, the installation further comprises a medium-pressure cold separator tank configured to separate the first liquid effluent comprising at least a light fraction into a second effluent liquid comprising at least a light fraction sent to the separation column (and a second gaseous effluent comprising hydrogen.

[0018] According to one or more embodiments of the invention, the installation further comprises: - a first heat exchanger configured to pre-cool the entire reaction effluent before sending it into said tubular charge-effluent heat exchanger; - a second heat exchanger configured to cool the bottom liquid from the separation column, and heat and send the second liquid effluent from the medium-pressure cold separator vessel to the separation column after additional heating in said first heat exchanger.

[0019] According to one or more embodiments of the invention, the installation further comprises: - a high-pressure hot separator vessel configured to separate the cooled reaction effluent from said tubular charge-effluent heat exchanger into a first liquid effluent comprising at least a heavy fraction and a first gaseous effluent comprising a light fraction sent to the high-pressure cold separator vessel after cooling in an external flow heat exchanger and passing through said first air condenser; - a medium-pressure hot separator vessel configured to separate the first liquid effluent comprising at least a heavy fraction into a second liquid effluent comprising at least a heavy fraction sent to the separation column, and a second gaseous effluent comprising a light fraction sent to said medium-pressure cold separator vessel after cooling in a second air condenser.

[0020] According to one or more embodiments of the invention, the tubular feed-effluent heat exchanger is provided with a plurality of inserts fixed to the tubes of said feed-effluent heat exchanger, each insert comprising an element having a rigid helical winding of a metal rod comprising several turns, preferably the element comprising: - a sequence of several successions of a first section of length L1 comprising a rigid helical winding of a metal rod comprising several turns and a second section of length L2 comprising a straight metal rod, and - a first end connected to a system for fixing said element to an inlet of said tube.

[0021] According to one or more embodiments of the invention, the insert element is rotationally mobile, said first end of the element being fixed to a mechanical link of the fastening system, said mechanical link allowing free rotation said element on itself around the axis (Z) of said tube under the action of the reaction effluent passing through said tube, and said rotating mobile element having a second free end opposite said first end.

[0022] According to one or more embodiments of the invention, the rotating moving element of the insert further comprises a rotating drive piece positioned between the first end of said element and connected to the first section of the sequence positioned first in the sequence, said rotating drive piece comprising a shaft coaxial with the helical winding of the first section and provided with at least two blades attached to said shaft.

[0023] According to one or more embodiments of the invention, the insert comprises: - a pitch pl of the helical winding of the first section between 10 mm and 50 mm; - a length L1 of the first section and a length L2 of the second section between 50 mm and 12,000 mm; - a total length of the insert L, between 50% and 100% of the total length L t of the heat exchanger feed-effluent tube, the total length of the tube Lt being between 500 mm and 6000 mm.

[0024] According to a second aspect, the present invention relates to a hydroconversion or hydrotreating process for a hydrocarbon feedstock, comprising the following steps: - preheat and send directly the hydrocarbon feed mixed with a hydrogen stream to a charging furnace by means of at least one tubular feed-effluent heat exchanger comprising a plurality of tubes through which a reaction effluent passes and comprising an insert in at least one of said tubes; - heat and send the preheated hydrocarbon feed-hydrogen stream mixture to a hydrotreating or hydroconversion reaction section using the feed furnace; - hydrotreat or hydroconvert the hydrocarbon feed in the hydrotreating or hydroconversion reaction section comprising at least one reactor comprising at least one catalyst comprising at least one element selected from the elements of Group VIII of the periodic table to form the reaction effluent; - to cool the reaction effluent from the hydrotreatment or hydroconversion reaction section by means of said tubular feed-effluent heat exchanger; - to lower the temperature of at least part of the reaction effluent from the tubular feed-effluent heat exchanger by means of a first air condenser before sending it into a high-pressure cold separator vessel; - separate said at least a part of the cooled reaction effluent from the first air-cooled condenser in the high-pressure cold separator vessel to form a first liquid effluent comprising at least a light fraction and a first gaseous effluent comprising hydrogen; and - separate the first liquid effluent comprising at least a light fraction in a separation column to form at least a bottom liquid and a top effluent.

[0025] According to one or more embodiments of the invention, the tubular feed-effluent heat exchanger is provided with a plurality of inserts fixed to the tubes of said tubular feed-effluent heat exchanger, each insert comprising an element having a rigid helical winding of a rod comprising several turns, preferably the element comprising: - a sequence of several successive sections of length L1 comprising a rigid helical winding of a rod with several turns and a second section of length L2 comprising a straight rod, and - a first end connected to a system for fixing said element to an inlet of said tube.

[0026] According to one or more embodiments of the invention, the hydrotreating or hydroconversion of the hydrocarbon feedstock is carried out with at least one of the following operating conditions: - the temperature is between approximately 200°C and approximately 550°C; - the total pressure is between approximately 1 MPa and approximately 38 MPa; - the overall hourly spatial velocity of liquid charge is between approximately 0.05 h 1 and approximately 12 h 1; - the hydrogen flow comprises between approximately 50% and approximately 100% of the volume of hydrogen relative to the volume of the hydrogen flow; - the quantity of hydrogen relative to the liquid hydrocarbon feedstock is between approximately 50 Nm3 / m3 and approximately 5000 Nm3 / m3

[0027] According to one or more embodiments of the invention, the hydrocarbon filler is chosen from: - feedstocks of fossil origin selected from diesel fuels, vacuum distillates, atmospheric residues, vacuum residues or Fischer-Tropsch unit effluents, - feedstocks derived from biomass conversion chosen from vegetable, algal, fish, or used food oils, fats of vegetable or animal origin, or oils produced from lignocellulosic biomass, - feedstocks from the conversion of waste chosen from pyrolysis oils of plastics, tires or solid recovered fuels, - and their mixtures.

[0028] According to one or more embodiments of the invention, the high-pressure cold separator vessel (B-2) is operated at a pressure lower than the pressure of the hydrotreating or hydroconversion reaction section (Rl) and / or in which the temperature of the high-pressure cold separator vessel (B-2) is between 20°C and 100°C.

[0029] According to one or more embodiments of the invention, the method further comprises the following steps: - pre-cool the entire reaction effluent from the hydrotreatment or hydroconversion reaction section (Rl) by means of a first heat exchanger (El) before sending it to the tubular feed-effluent heat exchanger (E-2); - separate said first liquid effluent comprising at least a light fraction from the high-pressure cold separator flask (B-2) into a medium-pressure cold separator flask (B-4) to form a second liquid effluent comprising at least a light fraction sent to the separation column (Cl) and a second gaseous effluent comprising hydrogen; - cool the bottom liquid from the separation column (Cl) and heat and send to said separation column (Cl) said second liquid effluent comprising at least a light fraction by means of a second heat exchanger (E-4); - heat said second liquid effluent comprising at least a light fraction from second heat exchanger (E-4) before sending it to said separation column (Cl) by means of said first heat exchanger (El).

[0030] Other objects and advantages of the invention will become apparent from the following description of particular embodiments of the invention, given by way of non-limiting examples, the description being made with reference to the attached figures described below. List of figures

[0031] [Fig.1]

[0032] Fig. 1 is a general diagram of an installation for implementing a hydroconversion or hydrotreatment process according to the present invention, in which the hydrocarbon feed of the reaction section is preheated by the reaction effluent in at least one tubular heat exchanger incorporating at least one insert, and then heated in a furnace before entering the reaction section.

[0033] [Fig.2]

[0034] Figure 2, derived from the general diagram of Figure 1, corresponds to a diagram of an installation for implementing a hydroconversion process or hydrotreatment according to a first embodiment of the invention following a scheme called the "cold" scheme.

[0035] [Fig.3]

[0036] Fig. 3, derived from the general diagram of Fig. 1, corresponds to a diagram of an installation for the implementation of a hydroconversion or hydrotreatment process according to a second embodiment of the invention following a diagram known as the "hot" diagram.

[0037] [Fig.4]

[0038] Fig. 4 represents an insert and its method of fixing to the tube of a single-phase heat exchanger, known from the prior art.

[0039] [Fig.5]

[0040] Fig. 5 is a three-dimensional (3D) schematic view of an example of an insert integrated into a tubular charge-effluent heat exchanger of an installation according to the invention.

[0041] [Fig.6]

[0042] Fig. 6 represents the same insert as that illustrated in Fig. 5, further showing a portion of a heat exchanger tube and a system for fixing the insert to the tube.

[0043] [Fig.7]

[0044] Fig. 7 represents a rear view of a portion of the insert and heat exchanger tube illustrated in Figures 6 and 7.

[0045] [Fig.8]

[0046] Fig. 8 is a schematic 3D view of another example of an insert integrated into a tubular charge-effluent heat exchanger of an installation according to the invention.

[0047] In the figures, the same references designate identical or analogous elements. Description of the implementation methods Terminology

[0048] In this description, the term "include" is synonymous with (means the same as) "comprise", "include", and "contain", thus being inclusive or open, and not excluding other elements not mentioned. It is understood that the term "include" includes the exclusive and closed term "consist".

[0049] In this description, the expression "between ... and ..." means that the limit values ​​of the interval are included in the range of values ​​described, unless otherwise specified.

[0050] Furthermore, in this description, the terms "essentially" or "substantially" or "approximately" in relation to a reference value correspond to An approximation of ±10%, ±5%, preferably ±1%, most preferably ±0.5%. This could be a value for temperature, pressure, distance, speed, flow rate, compound content, etc.

[0051] In the present description, the various parameter ranges characterizing a given device, or relating to a step in a process implementing said device, such as ranges relating to dimensions (lengths, diameters, etc.), angles, pressure ranges, or temperature ranges, may be used alone or in combination. For example, in the sense of the present invention, a preferred range of pressure values ​​may be combined with a more preferred range of temperature values.

[0052] According to the present invention, the pressures are absolute pressures, also noted as abs., and are given in absolute MPa (or abs. MPa), unless otherwise indicated.

[0053] In this description, the term "hydroconversion" refers to a process whose main purpose is to reduce the boiling point range of a hydrocarbon feedstock, and in which a substantial portion of the feedstock is converted into products with lower boiling point ranges than those of the original feedstock. Hydroconversion generally involves the fragmentation of larger hydrocarbon molecules into smaller molecular fragments with a smaller number of carbon atoms and a higher hydrogen-to-carbon ratio. The reactions carried out during hydroconversion reduce the size of hydrocarbon molecules, primarily by cleaving carbon-carbon bonds, in the presence of hydrogen to saturate the broken bonds and aromatic rings.The mechanism by which hydroconversion occurs typically involves the formation of hydrocarbon free radicals during fragmentation, primarily by thermal cracking, followed by the capping of the free radical terminations or fragments with hydrogen in the presence of active catalyst sites. Of course, during a hydroconversion process, other reactions typically associated with hydrotreating may occur, such as, among others, the removal of sulfur or nitrogen from the feedstock, or the saturation of olefins, as more broadly defined below.

[0054] The term "hydrotreating," commonly referred to as "HDT," refers to a milder operation than hydroconversion, the main purpose of which is to remove impurities such as sulfur, nitrogen, oxygen, halides, and trace metals from the feed, and to saturate olefins and / or stabilize hydrocarbon free radicals by causing them to react with hydrogen rather than allowing them to react with themselves. The main purpose is not to change the boiling point range of the feed. Thus, hydrotreating includes, among other things, hydrodesulfurization reactions (commonly called " HDS”), hydrodeazotation reactions (commonly called “HDN”) and hydrodemetallation reactions (commonly called “HDM”), accompanied by hydrogenation, hydrodeoxygenation, hydrodearomatization, hydroisomerization, hydrodealkylation, hydrocracking, hydrodeasphalting, and Conradson carbon reduction reactions. Hydrotreating is most often carried out using a fixed-bed reactor, although other reactors can also be used for hydrotreating, for example, a bubbling-bed hydrotreating reactor.

[0055] In this description, a hydroconversion or hydrotreating “catalyst” means a porous supported catalyst used in a hydroconversion or hydrotreating process of a hydrocarbon feedstock. In the remainder of this description, the term “catalyst” refers to such a hydroconversion or hydrotreating catalyst, unless otherwise specified. Such catalysts typically comprise (i) a catalyst support having a large surface area and numerous interconnected channels or pores, and (ii) an active phase in the form of fine particles of an active catalyst such as cobalt, nickel, tungsten, molybdenum sulfides, or mixed sulfides of these elements (e.g., NiMo, CoMo, etc.), dispersed in the pores. Supported catalysts are commonly produced as cylindrical extrudates (“pellets”) or spherical solids, although other shapes are possible.Such a catalyst is detailed further in the description.

[0056] In this description, the groups of chemical elements may be given according to the CAS classification (CRC Handbook of Chemistry and Physics, publisher CRC Press, editor-in-chief DR Lide, 81st edition, 2000-2001). For example, group VIII (or VIIIB) according to the CAS classification corresponds to the metals in columns 8, 9, and 10 according to the new IUP AC classification, and group VIb according to the CAS classification corresponds to the metals in column 6 according to the new IUP AC classification.

[0057] In this description, when mentioned, the positions "front", "rear", "horizontal", "vertical", etc. of the various elements of the insert and the heat exchanger tube are defined with respect to a tubular heat exchanger in the operating position and with respect to the direction of flow of the fluid passing through the heat exchanger tube.

[0058] In this description, the fluid flow velocity in the tube refers to the surface velocity of the fluid flowing in the tube V_SF, commonly understood to be the ratio between the volumetric flow rate of the fluid Q and the internal cross-section of the tube S: V_SF = Q / S. The same applies to the threshold speed for starting rotation of an insert, which is a surface velocity, more precisely a specific value of V_SF particular to the insert used.

[0059] In this description, "rigid" refers to the helical winding of a rod, preferably metallic, meaning a winding that does not deform, or hardly deforms, irreversibly under the action of the fluid that rotates the moving part containing said winding, under normal operating conditions of the heat exchanger tubes. In particular, said winding does not deform, or hardly deforms, irreversibly when the circulating fluid exhibits variations in speed, viscosity, and / or temperature.

[0060] In this description, a tube-side heat exchanger or tubular heat exchanger is defined as a heat exchanger comprising at least one tube inside which flows a fluid commonly referred to as the "tube-side fluid," exchanging heat with a fluid flowing outside said tube. The heat exchangers referred to in the present invention are classically shell-and-tube heat exchangers in which the tube-side fluid flows inside a set of parallel tubes called a tube bundle. These tubes are enclosed in a shell called a shell. The other fluid, called the "shell-side fluid," flows inside the shell but outside the tubes. The flow of the tube-side and shell-side fluids can be co-current and / or counter-current. The tubes are often long, typically up to 6 m, and of small diameter to optimize the surface area to volume ratio.They are generally held at their ends in perforated plates called tube sheets, which serve to support the tubes and also to separate the fluids, and may be supported between the tube sheets by intermediate support plates (perforated plates transverse to the tubes). The tubes may also be U-shaped, and their ends may, for example, be attached to a single tube sheet.

[0061] In the present description, a heat exchanger, such as the feed-effluent heat exchanger, is understood as operating only with fluids from the process, typically effluents produced in the process steps, unlike external flow heat exchangers, understood as heat exchangers in which one of the fluids involved in the heat transfer is external to the process, for example, water vapor external to the process.

[0062] In this description, the pitch of a helical winding comprising several turns is understood by the commonly accepted definition, which is the distance measured between the centers of two turns. In a two-dimensional representation, it is the distance between two crests on the same side of the winding axis, and in a 3D representation, it is the length (distance) between two turns around the axis of revolution of the turn (or the distance traveled along the axis of revolution of the turn to make one complete turn).

[0063] Embeddings of the installation and implementation of the method are described in detail below. Numerous specific details are presented to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the installation and the method can be implemented without necessarily including all of these specific details. In other cases, well-known features have not been described in detail to avoid unnecessarily complicating the description.

[0064] In the present description, the different embodiments presented can be implemented separately or in combination with each other, without limitation of combinations when this is technically feasible.

[0065] The present invention relates to an installation and a method for hydrotreating or hydroconverting a hydrocarbon feedstock, such as installations and methods for hydroconverting heavy feedstocks, for example, residues or vacuum diesel. The present invention also relates to an installation and a method for hydrotreating, such as installations and methods for hydrodemetallation, hydrodeazotation, and / or hydrodesulfurization of residues or diesel.

[0066] The present invention thus proposes an installation and a method for hydrotreating or hydroconverting a hydrocarbon feed comprising at least one tubular feed-effluent heat exchanger (E-2) equipped with inserts.

[0067] Hydrotreatment or hydroconversion installation / process

[0068] Reference is first made below to figures 1 to 3 to describe the installation and the hydrotreatment or hydroconversion process according to the invention.

[0069] Reference will be made below to figures 5 to 8 to describe examples of inserts, which are not limiting, that are integrated into the tubular charge-effluent heat exchanger E-2 of the installation.

[0070] According to the invention, inserts can also be used in other heat exchangers than the tubular charge-effluent heat exchanger E-2 within the installation, such as the known insert illustrated in [Fig.4], or the same types of inserts as those used in the tubular charge-effluent heat exchanger E-2 and illustrated in the other figures 5-8.

[0071] The hydrotreating or hydroconversion plant according to the invention comprises at least one tubular feed-effluent heat exchanger E-2 configured to preheat and directly send the hydrocarbon feed mixed with a hydrogen stream to a feed furnace Fl of a hydrotreating or hydroconversion reaction section Rl, and to cool a reaction effluent from the hydrotreating or hydroconversion reaction section RL

[0072] The tubular charge-effluent heat exchanger E-2 comprises a plurality of tubes 10 through which a fluid, in this case the reaction effluent, flows, and comprises an insert in at least one of said tubes, preferably fixed at the upstream end of the less one of said tubes. In this description, upstream and downstream are understood with respect to the direction of fluid flow. The E-2 tubular feed-effluent heat exchanger is a two-phase heat exchanger, that is to say, configured for the circulation of a gas phase and a liquid phase within said tubes.

[0073] In the tubular feed-effluent heat exchanger E-2, the two fluids, tube-side and shell-side, are two-phase. The fluid on the tube side of the heat exchanger E-2 comprises a gas phase and a liquid phase: the reaction effluent passing through the tubes comprises a liquid phase and a vapor phase containing, in particular, H2, NH3, H2S, and some of the vaporized products. The hydrocarbon feed-hydrogen flow mixture to be heated, circulating on the shell-side, therefore also comprises a gas phase, e.g., gaseous hydrogen, and a liquid phase, e.g., the hydrocarbon feed. The installation according to the invention further comprises: - the charging furnace Fl configured to heat and send the preheated hydrocarbon charge-hydrogen flux mixture to the hydrotreating or hydroconversion reaction section Rl; - the hydrotreating or hydroconversion reaction section Rl configured to hydrotreat or hydroconvert the hydrocarbon feedstock and produce the reaction effluent; - a high-pressure cold separator vessel B-2 configured to separate at least a portion of the cooled reaction effluent into a first liquid effluent comprising at least a light fraction and a first gaseous effluent comprising hydrogen; and - a C-1 separation column configured to separate said first liquid effluent into at least a bottom liquid and a top effluent.

[0074] With reference to [Fig. 1], a hydrotreatment or hydroconversion plant according to the invention for hydrocarbon feedstocks, such as hydrocarbon feedstocks of fossil origin or from the conversion of biomass or waste, taken alone or in mixtures, comprises: - at least one tubular feed-effluent heat exchanger E-2, typically of shell-and-tube type, for example one or more tubular feed-effluent heat exchanger trains E-2, configured to preheat a mixture of the hydrocarbon feed (line 1) with a hydrogen stream (line 4), hereafter referred to as the hydrocarbon feed-hydrogen stream mixture (line 5), with the reaction effluent (line 8), possibly pre-cooled in an optional heat exchanger El (line 9), from a hydrotreating or hydroconversion reaction section Rl; - a charging furnace Fl configured to heat the hydrocarbon feed-preheated hydrogen stream mixture (line 6) from the feed-effluent heat exchanger tubular E-2 and send the heated hydrocarbon feed-hydrogen flow mixture (line 7) to the hydrotreating or hydroconversion reaction section Rl; - the hydrotreating or hydroconversion reaction section Rl; - optionally a first heat exchanger E-1 configured to pre-cool all of the reaction effluent (line 8) before sending it into said tubular charge-effluent heat exchanger E-2; - optionally a high-pressure hot separator vessel Bl, the charge of which consists of the reaction effluent cooled after passing through the tubular charge-effluent heat exchanger or heat exchanger(s) train(s) E-2 (line 10), configured to separate a first liquid effluent comprising at least a heavy fraction (line 17) and a first gaseous effluent comprising a light fraction (line 11), said first gaseous effluent comprising a light fraction being sent to the high-pressure cold separator vessel (B-2) after cooling in an external flow heat exchanger (E-3), possible addition of water (line 13) to limit the risks of ammonium salt deposits and therefore corrosion, and passing through a first air condenser (Al); - a high-pressure cold separator vessel B-2, the charge of which includes at least a portion of the reaction effluent from the hydrotreating or hydroconversion reaction section Rl and cooled at least after passing through the tubular charge-effluent heat exchanger(s) E-2 (lines 10, 11, 12 and 14), configured to separate a first liquid effluent comprising at least a light fraction (line 20) and a first gaseous effluent comprising hydrogen (line 15); - optionally an external flow heat exchanger E-3 configured to cool at least a portion of the reaction effluent (or optionally the first gaseous effluent comprising a light fraction from the high-pressure hot separator vessel Bl); - the first air condenser Al to lower the temperature of at least part of the reaction effluent cooled by the tubular charge-effluent heat exchanger E-2 before it is sent to the high-pressure cold separator vessel B-2 (or optionally to condense the first gaseous effluent including a light fraction from the high-pressure hot separator vessel Bl and optionally also from the second heat exchanger E-3); - optionally a medium-pressure hot separator vessel B-3, the charge of which is the first liquid effluent comprising at least a heavy fraction (line 17) from the high-pressure hot separator vessel Bl, and configured to separate said first liquid effluent comprising a heavy fraction into a second liquid effluent comprising at least a heavy fraction (line 21) which is sent to a separation column Cl, and a second gaseous effluent comprising a fraction light (line 18) sent to a medium-pressure cold separator balloon (B-4) after possible cooling in a second air condenser A-2; - optionally the second air condenser A-2 configured to condense the second gaseous effluent including a light fraction (line 18) from the medium pressure hot separator vessel B-3 and form a second gaseous effluent including a condensed light fraction (line 19); - optionally a medium-pressure cold separator B-4, configured to separate the first liquid effluent comprising at least a light fraction (line 20) from the high-pressure cold separator B-2 (and optionally the second gaseous effluent comprising a light fraction (line 18) from the medium-pressure hot separator B-3 (and optionally condensed (line 19) in the second air-cooled condenser A-2)), into a second liquid effluent comprising at least a light fraction (lines 22 and 24) sent to the separation column Cl, and a second gaseous effluent comprising hydrogen which is subtracted from said spar;- optionally a second heat exchanger E-4 configured to heat the feed of the separation column Cl, more specifically configured to heat and send the second liquid effluent comprising at least a light fraction from the medium-pressure cold separator vessel B-4 to the separation column Cl after possible additional heating in the first heat exchanger E-1 (line 22, line 23, and line 24), and to cool the bottom liquid from the separation column C-1; - the separation column Cl (e.g., conventional fractionation column or stripping column using a fluid added by line 25) to form a bottom liquid (line 26) and a top effluent (line 28) from the liquid effluent (line 20) from the high-pressure cold separator tank B-2, optionally from the high-pressure hot separator tank Bl (line 17), optionally from the medium-pressure hot separator tank B-3 (line 21), optionally from the medium-pressure cold separator tank B-4 (line 22); - optionally a second furnace (not shown) adapted to heat the bottom liquid of the separation column (e.g. after passing through the second heat exchanger E-4) and distribute it to a fractionation column (not shown); - optionally a third heat exchanger (not shown) adapted to cool or heat the first or second liquid effluent comprising at least a heavy fraction. - optionally a third air condenser A-3 to condense the head effluent (line 28) from the separation column Cl and form a condensed head effluent (line 29); - optionally a B-5 reflux flask to separate the overhead effluent or condensed overhead effluent into a overhead gaseous fraction (e.g. acid gas) (line 31) and a hydrocarbon liquid cut (e.g. naphtha) (line 30); - optionally an amine scrubbing column C-2 allowing to remove at least part of the H2S from the first gaseous effluent containing hydrogen (line 15) from the high pressure cold separator tank B-2, also called recycled hydrogen;

[0075] - optionally a first compression section Kl of recycled hydrogen and washed with amines (line 16); - optionally a second K-2 booster hydrogen compression section (line 2) forming compressed booster hydrogen (line 3) which can be mixed with the recycled, washed and compressed hydrogen from the first Kl compression section.

[0076] The tubular feed-effluent heat exchanger E-2 is arranged to heat the hydrocarbon feed-hydrogen flux mixture with the reaction effluent.

[0077] The hydrocarbon load targeted by hydrotreatment and / or hydroconversion can be of a different nature.

[0078] The feedstock may be of fossil origin or derived from the conversion of biomass or waste, alone or in mixtures. The feedstocks that are treated, and in particular those mentioned below, generally contain heteroatoms such as sulfur, oxygen and nitrogen and may contain other contaminants such as iron, titanium, silicon, calcium, sodium, potassium, chlorine and arsenic, but also, particularly for heavier feedstocks, nickel and vanadium.

[0079] The fossil fuel feedstock may include, in particular, a fraction derived from coal or hydrocarbons produced from natural gas, possibly in mixtures. It may also consist of heavy petroleum or synthetic fractions, for example, kerosene, gas oil, or distillates obtained by atmospheric and vacuum distillation to produce usable kerosene, gas oil, or vacuum distillate, either in the storage unit receiving products of the same type (a "pool") or to a downstream unit such as a catalytic cracking unit, where the feedstocks are "cracked" to produce shorter-chain hydrocarbons. It is common for the hydrotreating process to be, in fact, a preliminary step in the treatment of a feedstock by a hydroconversion / hydrocracking process.

[0080] The fossil-based feedstocks used in a hydrotreating process, in more detail, are for example gasoline, diesel fuel, vacuum diesel fuel, atmospheric residues, vacuum residues, atmospheric distillates, vacuum distillates, heavy fuel oils, oils, waxes and paraffins, oils used materials, residues or deasphalted crudes, feedstocks from thermal or catalytic conversion processes, taken alone or in mixtures.

[0081] The feedstock resulting from biomass conversion may advantageously be selected from vegetable oils, algae or algal oils, fish oils, used cooking oils, and fats of vegetable or animal origin; or mixtures of such feedstocks. Said vegetable oils may advantageously be crude or refined, wholly or partially, and derived from plants selected from rapeseed, sunflower, soybean, palm, olive, coconut, copra, castor, cottonseed, peanut, linseed, and crambe oils, and all oils derived, for example, from sunflower or rapeseed by genetic modification or hybridization, this list not being exhaustive. Said animal fats are advantageously selected from lard and fats composed of residues from the food industry or from the catering industry.Frying oils, various animal oils such as fish oil, tallow, and lard can also be used. The feedstock from biomass conversion can also advantageously be chosen from among methyl esters of fatty acids of vegetable and / or animal origin, or from methyl esters of fatty acids from used edible vegetable oils.

[0082] The feedstock resulting from biomass conversion can also be selected from feedstocks obtained from thermal or catalytic biomass conversion processes, such as oils produced from biomass, particularly lignocellulosic biomass, using various liquefaction methods, such as hydrothermal liquefaction or pyrolysis. The term "biomass" refers to material derived from recently living organisms, including plants, animals, and their by-products. The term "lignocellulosic biomass" refers to biomass derived from plants or their by-products. Lignocellulosic biomass is composed of carbohydrate polymers (cellulose, hemicellulose) and an aromatic polymer (lignin).

[0083] The feed from biomass conversion can also advantageously be chosen from feeds from the paper industry.

[0084] The feedstock from waste conversion can be a pyrolysis oil derived from plastics, tires, or solid recovered fuels (SRF). These oils are obtained by thermal pyrolysis, catalytic pyrolysis, or hydropyrolysis (pyrolysis in the presence of a catalyst and hydrogen).

[0085] According to one or more embodiments, the hydrocarbon filler is chosen from: - feedstocks of fossil origin selected from diesel fuels, vacuum distillates, atmospheric residues, vacuum residues or Fischer-Tropsch unit effluents, - feedstocks derived from biomass conversion chosen from vegetable, algal, fish, or used food oils, fats of vegetable or animal origin, or oils produced from lignocellulosic biomass, - feedstocks from the conversion of waste chosen from pyrolysis oils of plastics, tires or RDF, - and their mixtures.

[0086] According to one or more embodiments, the initial boiling point of the hydrocarbon charge is greater than 120°C.

[0087] In the case of diesel, the initial distillation point is generally around 150°C and the distillation range is typically between 170°C and 390°C. In the case of atmospheric residue, the initial distillation point is typically above 300°C, preferably between 340°C and 380°C. In the case of vacuum residue, the initial distillation point is typically between 450°C and 600°C, preferably between 500°C and 550°C. Light vacuum gas oil (LVGO) is characterized by a distillation range between 300°C and 430°C, preferably between 340°C and 400°C. Heavy vacuum gas oil (HVGO) is characterized by a distillation range between 400°C and 620°C, preferably between 440°C and 550°C. The usable feedstocks therefore fall within a wide range of boiling points.

[0088] According to one or more embodiments, the hydrocarbon filler contains at least 10% by volume, generally at least 20% by volume, preferably at least 30% by volume, and often at least 40% by volume, or even at least 80% by volume of compounds boiling above 340°C.

[0089] According to one or more embodiments, the nitrogen content of the hydrocarbon feed is greater than 500 ppm by weight, generally between 500 ppm and 10000 ppm by weight, more generally between 700 ppm and 4500 ppm by weight and even more generally between 800 ppm and 4500 ppm by weight.

[0090] According to one or more embodiments, the sulfur content of the hydrocarbon filler is between 0.01 and 5% by weight, generally between 0.2 and 4% by weight and even more generally between 0.5 and 3% by weight.

[0091] According to one or more embodiments, the hydrocarbon filler contains metals. According to one or more embodiments, the cumulative nickel and vanadium content of the hydrocarbon filler is less than 20 ppm by weight, preferably less than 10 ppm by weight, and even more preferably less than 5 ppm by weight.

[0092] According to one or more embodiments, the asphaltene content of the hydrocarbon filler is less than 4000 ppm by weight, preferably less than 1000 ppm by weight, even more preferably less than 300 ppm by weight.

[0093] According to one or more embodiments, the reaction effluent of the hydrotreating or hydroconversion reaction section Rl consists of a hydrocarbon cut, generally in mixed phase, comprising hydrogen, gases from cracking, and in particular H2S and NH3 from the reactions of said reaction section, in proportion to the sulfur and nitrogen content contained in the feed, possibly CO2 and other gases, light cuts such as LPG (or LPG for liquefied petroleum gas) from secondary reactions, and at least naphtha, and possibly the following hydrocarbon cuts: diesel, kerosene and / or unconverted residue, etc., depending on the nature of the feed and the type of reaction.

[0094] According to one or more embodiments, the first liquid effluent comprising at least one heavy fraction includes at least a portion of the heaviest fraction of the reaction section effluent, comprising naphtha, diesel, kerosene, and / or unconverted residue, depending on the nature of the feedstock and the type of reaction. The first liquid effluent comprising at least one heavy fraction may also include an intermediate fraction of the reaction section effluent, optionally comprising diesel, kerosene, and / or naphtha, depending on the nature of the feedstock and the type of reaction.

[0095] According to one or more embodiments, the first gaseous effluent comprising a light fraction includes at least a portion of the lightest fraction of the reaction effluent, comprising hydrogen, gases from cracking, and in particular H2S and NH3 from the reactions of the reaction section, in proportion to the sulfur and nitrogen content contained in the feed, optionally CO2 and other gases, light cuts such as LPGs from secondary reactions, and at least naphtha.

[0096] According to one or more embodiments, the first liquid effluent comprising at least a light fraction includes a fraction of the reaction effluent comprising light cuts such as LPGs from secondary reactions, and at least naphtha.

[0097] According to one or more embodiments, the first gaseous effluent comprising hydrogen includes gases from cracking, and in particular H2S from the reactions of the reaction section, in proportion to the sulfur content contained in the feed, possibly CO2.

[0098] According to one or more embodiments, the second liquid effluent comprising at least one heavy fraction comprises the heaviest fraction of the effluent from the reaction section, comprising diesel, kerosene and / or unconverted residue depending on the nature of the feedstock and the type of reaction.

[0099] According to one or more embodiments, the second gaseous effluent comprising a light fraction includes a first intermediate fraction of the effluent from the reaction section, possibly comprising diesel, kerosene, and / or naphtha depending on the nature of the feedstock and the type of reaction.

[0100] According to one or more embodiments, the second liquid effluent comprising at least a light fraction includes the heaviest fraction of the first liquid effluent comprising at least a light fraction. The second liquid effluent comprising at least a light fraction may also include a second intermediate fraction of the reaction section effluent comprising diesel, kerosene, and / or naphtha, depending on the nature of the feedstock and the type of reaction.

[0101] According to one or more embodiments, the second gaseous effluent comprising hydrogen includes at least a portion of the lightest fraction of the reaction effluent, comprising hydrogen, gases from cracking, and in particular H2S from the reactions of the reaction section, in proportion to the sulfur content contained in the feed, possibly CO2 and other gases.

[0102] According to one or more embodiments, the head effluent comprises gases from cracking, and in particular H2S, possibly CO2 and other gases, LPGs, naphtha and possibly the stripping fluid.

[0103] According to one or more embodiments, the head gaseous fraction comprises gases from cracking, and in particular H2S, possibly CO2 and other gases, LPGs.

[0104] According to one or more embodiments, the hydrocarbon liquid cut comprises naphtha.

[0105] According to one or more embodiments, the bottom liquid comprises the heaviest fraction of the effluent from the reaction section, including diesel, kerosene and / or unconverted residue depending on the nature of the feed and the type of reaction.

[0106] In the installation described herein, the hydrotreating or hydroconversion reaction section Rl may comprise one or more reactors arranged in series or in parallel, for example, two reactors arranged in series. Each reactor in the reaction section comprises at least one catalyst bed. The catalyst may be implemented as a fixed bed, an expanded bed, or a bubbling bed. In the case of a catalyst implemented as a fixed bed, it is possible to have several catalyst beds in at least one reactor.

[0107] According to one or more embodiments, the hydrotreating or hydroconversion reaction section Rl is the reaction section of a hydrocracking plant.

[0108] According to one or more embodiments, the hydrotreating or hydroconversion reaction section Rl is the reaction section of a vacuum hydrodesulfurization plant for diesel or kerosene or distillate.

[0109] According to one or more embodiments, the hydrotreating or hydroconversion reaction section Rl is the reaction section of a naphtha hydrodesulfurization plant.

[0110] According to one or more embodiments, the hydrotreating or hydroconversion reaction section Rl is included in a boiling bed hydroconversion plant for residue or distillate or deasphalted oil.

[0111] The Cl separation column is designed, in particular, to remove gases produced by cracking (generally called acid gases), and especially H2S from the reactions in the reaction section. This column is preferably stripped using any stripping gas, such as, for example, a gas containing hydrogen or steam. Steam is preferably used to perform said stripping.

[0112] According to the second aspect, the present description also relates to a method of implementing the installation according to the first aspect.

[0113] The method according to the invention, advantageously implementing the installation according to the invention, comprises the following steps: - preheat and send directly the hydrocarbon feed mixed with a hydrogen stream to a charging furnace by means of at least one tubular feed-effluent heat exchanger E-2 comprising a plurality of tubes 10 through which a fluid flows and comprising an insert fixed to the upstream end of at least one of said tubes; - heat and send the preheated hydrocarbon feed-hydrogen stream mixture to a hydrotreating or hydroconversion reaction section Rl by means of the charging furnace Fl; - hydrotreat or hydroconvert the hydrocarbon feed in the hydrotreating or hydroconversion reaction section Rl comprising at least one reactor comprising at least one catalyst comprising at least one element selected from the elements of Group VIII of the periodic table; - to cool the reaction effluent from the hydrotreatment or hydroconversion reaction section Rl by means of said tubular charge-effluent heat exchanger E-2; - lower the temperature of at least part of the reaction effluent from the tubular charge-effluent heat exchanger E-2 by means of a first air condenser Al before sending it into a high-pressure cold separator vessel B-2; - separate said at least a portion of the cooled reaction effluent in the high-pressure cold separator vessel B-2 to form a first liquid effluent comprising at least a light fraction and a first gaseous effluent comprising hydrogen; and - separate the first liquid effluent comprising at least a light fraction in a separation column Cl to form at least a bottom liquid and a top effluent.

[0114] According to one or more embodiments, the tubular feed-outlet heat exchanger E-2 is provided with a plurality of inserts fixed to the tubes of said tubular feed-outlet heat exchanger, and each insert comprising an element 100 having a rigid helical winding of a rod, preferably metallic, comprising several turns. Preferably, the element 100 is as described in relation to Figures 5 to 7 or 8, and comprises: - a sequence of several successions of a first section SI of length L1 comprising a rigid helical winding of a rod, preferably metallic, comprising several turns and a second section S2 of length L2 comprising a straight rod, preferably metallic, and - a first end connected to the fixing system 200 of the element 100 to an inlet of the tube 110.

[0115] According to one or more implementations, the process includes the following steps: - pre-cooling all of the reaction effluent from the hydrotreating or hydroconversion reaction section Rl by means of a first heat exchanger El before sending it to the tubular feed-effluent heat exchanger E-2; - lower the temperature of said cooled reaction effluent from the tubular charge-effluent heat exchanger E-2 by means of a first air cooler Al before sending it into said high-pressure cold separator vessel B-2; - separate said first liquid effluent comprising at least a light fraction from the high-pressure cold separator flask B-2 into a medium-pressure cold separator flask B-4 to form a second liquid effluent (comprising at least a light fraction) sent to the separation column C-1 and a second gaseous effluent comprising hydrogen; - cool the bottom liquid from the separation column Cl and heat and send to said separation column Cl said second liquid effluent comprising at least a light fraction by means of a second heat exchanger E-4; - heat said second liquid effluent comprising at least a light fraction from second heat exchanger E-4 before sending it to said separation column Cl by means of said first heat exchanger El.

[0116] According to one or more embodiments, the operating conditions of the hydrotreating or hydroconversion reaction section Rl include at least one of the following characteristics: - the temperature is between approximately 200 and approximately 550°C, preferably between approximately 200°C and 460°C; - the total pressure is between approximately 1 MPa and approximately 38 MPa, such as between 2 MPa and 20 MPa, preferably between 2.5 MPa and 18 MPa, and most preferably between 3 MPa and 18 MPa; - the overall hourly spatial velocity of liquid charge for each catalytic step is between approximately 0.05 h' and approximately 12 h1, and preferably between approximately 0.1 h 1 and approximately 10 h 1; - the purity of the hydrogen used is between approximately 50 and 100% by volume relative to the volume of the hydrogen input (i.e., recycled hydrogen / make-up hydrogen mixture); and - the quantity of hydrogen relative to the liquid hydrocarbon charge is between approximately 50 Nm³ / m³ and approximately 5000 Nm³ / m³, preferably between approximately 50 Nm³ / m³ and approximately 2500 Nm³ / m³.

[0117] Any catalyst known to a person skilled in the art can be used in the process according to this description, for example a catalyst comprising at least one element selected from the elements of Group VIII of the periodic table (groups 8, 9 and 10 of the new periodic table) and possibly at least one element selected from the elements of Group VIB of the periodic table (group 6 of the new periodic table).

[0118] For the implementation of the process according to the invention, a conventional hydroconversion catalyst can be used, comprising, on an amorphous support, at least one metal or metal compound having a hydro-dehydrogenating function. This catalyst can be a catalyst comprising metals from group VIII, for example nickel and / or cobalt, most often in combination with at least one metal from group VIB, for example molybdenum and / or tungsten. For example, a catalyst comprising 0.5 to 10% by weight of nickel (expressed as nickel oxide NiO) and 1 to 30% by weight of molybdenum, preferably 5 to 20% by weight of molybdenum (expressed as molybdenum oxide MoO3) relative to the total weight of the catalyst, can be used on an amorphous mineral support. The total content of metal oxides of groups VIB and VIII in the catalyst is generally between 5 and 40% by weight and preferably between 7 and 30% by weight relative to the total weight of the catalyst.The weight ratio (expressed on the basis of metal oxides) between metal(s) of group VIB and metal(s) of group VIII is, in general, about 20 to about . 1, and most often from about 10 to about 2. The support is, for example, chosen from the group formed by alumina, silica, silica-aluminas, magnesia, clays, and mixtures of at least two of these minerals. This support may also contain other compounds and, for example, oxides chosen from boron oxide, zirconia, titanium oxide, and phosphoric anhydride.

[0119] Another type of usable catalyst is one containing at least one matrix, at least one zeolite Y, and at least one hydro-dehydrogenating metal. The matrices, metals, and additional elements described above may also be included in the composition of this catalyst. Advantageous zeolites Y are described in patent application WO00 / 71641, as well as in patents EP0911077, US4738940, and US4738941.

[0120] According to one or more embodiments, the high-pressure cold separator vessel B-2 is operated at a pressure lower than that of the hydrotreating or hydroconversion reaction section Rl or the high-pressure hot separator vessel Bl, for example, a pressure 0.1 MPa to 1.0 MPa lower than that of the hydrotreating or hydroconversion reaction section Rl or the high-pressure hot separator vessel BL

[0121] The temperature of the high-pressure cold separator vessel B-2 is generally kept as low as possible given the available cooling means. This is to maximize the purity of the recycled hydrogen. The temperature of the high-pressure cold separator vessel B-2 is generally between 20°C and 100°C, preferably between 35°C and 70°C. The first liquid effluent, including at least a light fraction, from the high-pressure cold separator vessel B-2 is sent to the separation column Cl, preferably of the stripper type, preferably equipped with the reflux vessel B-6.

[0122] According to one or more embodiments, the cooled reaction effluent is sent to the optional hot high-pressure separator vessel Bl operated at a lower pressure, for example a pressure 0.1 MPa to 1.0 MPa lower than that of the hydrotreating or hydroconversion reaction section RL. The temperature of the hot high-pressure separator vessel Bl is generally between 200°C and 450°C, preferably between 250°C and 380°C and most preferably between 260°C and 360°C.

[0123] According to one or more embodiments, the first liquid effluent comprising at least a heavy fraction from the high-pressure hot separator tank Bl is sent to a first valve Vl or an optional turbine and directed to the optional medium-pressure hot separator tank B-3, the pressure of which is chosen so as to be able to supply the optional medium-pressure cold separator tank B-4 with the second liquid effluent comprising at least a heavy fraction from the medium-pressure hot separator tank B-3.

[0124] According to one or more embodiments, the medium-pressure hot separator vessel B-3 is operated at a pressure between 1.0 and 5.0 MPa, preferably between 1.5 and 3.5 MPa. The temperature of the medium-pressure hot separator vessel B-3 is generally between 150°C and 380°C, preferably between 200°C and 360°C.

[0125] According to one or more embodiments, the first liquid effluent, comprising at least a light fraction from the high-pressure cold separator vessel B-2, is expanded in a second valve V-2 or an optional turbine and directed to the optional medium-pressure cold separator vessel B-4. The total pressure of the medium-pressure cold separator vessel B-4 is preferably that required to efficiently recover the hydrogen contained in the second gaseous effluent, which includes hydrogen separated in said vessel B-4. This hydrogen recovery is preferably carried out in a pressure-reversing adsorption unit. The total pressure of the medium-pressure cold separator vessel B-4 is generally between 1.0 MPa and 5.0 MPa, preferably between 1.5 MPa and 3.5 MPa. The temperature of the medium-pressure cold separator vessel B-4 is generally between 20°C and 100°C, preferably between 25°C and 70°C.

[0126] The bottom liquid (line 26) of the separation column Cl can be heated via the fourth heat exchanger E-4 before being sent via line 27 to a fractionation section (not shown) which allows the separation of naphtha, kerosene, diesel and residue cuts.

[0127] The inventors have demonstrated that it is possible to implement inserts adapted to tubular feed-effluent type heat exchangers in a hydrotreatment or hydroconversion plant for a hydrocarbon feed, capable of meeting significant pressure drop constraints, and in particular of operating with minimal pressure drop variation, and thus conferring the following advantages to the plant and process according to the invention: - increasing the treatment capacity of the plant / process, and / or - lower capital expenditure (CAPEX) on heat exchangers by allowing the use of smaller heat exchangers for a given plant / process capacity, and / or - to provide flexibility in the operation of the installation and the process in case of variation in the load being processed, particularly in terms of fouling power.

[0128] In certain cases, such as that of a detailed cold scheme below in relation to [Fig. 2], it is also very advantageously possible to preheat the hydrocarbon feed-hydrogen flow mixture more efficiently so that the The required consumption of the Fl charging furnace is lower, limiting CO2 consumption.

[0129] Figures 1, 2 and 3 show the same numbering for the same equipment of the hydrotreatment or hydroconversion plant.

[0130] Figure 2 illustrates an example of a first embodiment of the invention.

[0131] According to this first embodiment of the invention, the hydrotreating or hydroconversion installation and process follow a so-called "cold" scheme, which is a classic scheme for hydrotreating middle distillates, in which the separation section, comprising at least one separation vessel, is operated at a low temperature. This type of scheme limits hydrogen losses, particularly because the transition of hydrogen to the liquid phase is limited from a thermal point of view, compared to a so-called "hot" scheme. However, this type of cold scheme generally requires a larger heat exchange surface area and implies higher furnace power consumption and a larger separation section.

[0132] The hydrotreatment or hydroconversion installation according to this first embodiment of the invention comprises all the elements of the installation described in relation to [Fig. 1], which are not repeated here, and further comprises the following element, which is no longer optional: - the medium pressure cold separator tank B-4.

[0133] Preferably, and as illustrated in [Fig.2], the following devices are also no longer optional: - the first heat exchanger El, and - the second heat exchanger E-4.

[0134] The integration of inserts into the tubular feed-effluent heat exchanger E-2 is particularly advantageous in a cold scheme such as that applied by the installation / process according to this first embodiment of the invention. While it is possible according to this first embodiment to increase treatment capacity, reduce CAPEX, particularly by using smaller heat exchangers for a given treatment capacity, or to provide operational flexibility to handle variable loads that can lead to more or less significant fouling, a major advantage of this first embodiment lies in the reduction of CO2 emissions.Indeed, the gains in fuel consumption of the charging furnace Fl, and possibly in energy consumption of the air cooler Al, due to improved heat exchange and reduced fouling, are significant, and help to limit CO2 emissions and therefore the environmental impact of the process.

[0135] Figure 3 illustrates an example of a second embodiment of the invention.

[0136] According to this second embodiment of the invention, the hydrotreating or hydroconversion installation and process follow a so-called "hot" scheme, which is also a conventional hydrotreating scheme for heavier feedstocks such as middle distillates, in which the separation section includes at least one separation vessel operated at a high temperature. This type of scheme, compared to the cold scheme, reduces the exchange surface area, decreases the fuel consumption of the feed furnace, and allows for the processing of heavier feedstocks. However, hydrogen losses due to its dissolution, and consequently the hydrogen replenishment, are greater. The cost of hydrogen can make this type of process economically unviable.In general, in a hot scheme, the hot separation vessel(s) operate at the outlet temperature of the hydrotreating or hydroconversion reaction section reactor (Rl) and at the reactor pressure.

[0137] In this type of hot process, the overall thermal performance of the feed / effluent heat exchangers is generally limited by the specifications imposed on the inlet and outlet. Therefore, improving the heat transfer of the tubular feed-effluent heat exchanger(s) incorporating inserts according to the invention has little overall impact on the energy consumption of the feed furnace Fl, but allows for increased processing capacity and / or reduced CAPEX, particularly with the possibility of using smaller heat exchangers for a given processing capacity, and / or providing operational flexibility to process loads with varying fouling potential.

[0138] The hydrotreatment or hydroconversion installation according to this second embodiment of the invention comprises all the elements of the installation described in relation to [Fig. 1], which are not repeated here, the following elements no longer being optional: - the medium pressure cold separator tank B-4, - the high pressure hot separator tank Bl, and - the medium pressure hot separator tank B-3.

[0139] Preferably, and as illustrated in [Fig.3], the following devices are also no longer optional: - the first El heat exchanger, - the second heat exchanger E-4, - the second air-cooled condenser A-2, and - the external flow heat exchanger E-3. Inserts

[0140] Advantageously, the tubular charge-effluent heat exchanger E-2 is provided with a plurality of inserts fixed to the tubes of said charge-effluent heat exchanger.

[0141] Figures 5 to 8 illustrate examples of inserts that can be integrated into the tubes of the tubular charge-effluent heat exchanger(s) E-2.

[0142] Preferably, each insert comprises an element 100 having a rigid helical winding of a rod, preferably metallic, comprising several turns.

[0143] According to one or more embodiments, shown in figures 5 to 7, the insert comprises an element 100 comprising a series of several successions of a first section SI of length L1 comprising a rigid helical winding of a rod, preferably metallic, comprising several turns and of a second section S2 of length L2 comprising a straight rod, preferably metallic.

[0144] The element 100 comprises a first end, advantageously connected to a fixing system 200 of said element 100 to an inlet of said tube 110, visible in [Fig.6].

[0145] The succession consisting of a first section SI comprising a rigid helical winding of a rod having several turns and a second section S2 comprising a straight rod is repeated n times in the sequence.

[0146] The sequences are preferably identical to each other, i.e., have the same geometric characteristics (e.g., same lengths L1 and L2, pitch of the first section, thickness of the rods, etc.). However, a sequence of sequences that differ from each other does not fall outside the scope of the present invention. For example, the value of the length L1 and / or L2 may be the same from one sequence to the next or may be different. For example, the length L1 of the first section SI of the first sequence in the sequence may be different from the length L1 of the section SI of the following sequences, because it is the first section SI of the first sequence that primarily drives the rotation of the rest of the insert.

[0147] The total length of the insert L is essentially equal to the sum of the lengths L1 and L2 of all the sequences S1 / S2. The length L! can be equal to n times the sum of the lengths L1 and L2 if the lengths L1 and L2 are identical from one sequence to the next.

[0148] Permanent joining means can connect the first section SI and the second section S2, as well as the sequences between them, to form an element 100 in the form of a single part. Such permanent joining means are, for example, welds or any other suitable permanent joining means for said parts. Alternatively, the first section SI and the second section S2, as well as the sequences between them, form an element 100 in the form of a single part without joining means, the different parts being manufactured directly as a single piece. Alternatively again (not shown), non-permanent joining means, preferably detachable, such as a hook-washer assembly or any other suitable joining means, are used to connect the first section SI and second section S2, as well as the successions between them to form an element 100 in the form of separate parts connected so as to be mechanically joined.

[0149] The first SI section of the sequence positioned first in the sequence from the entrance of the tube 110 originates at the first end of the element 100.

[0150] The element 100 may be static, but is preferably rotationally mobile during its operation in said tube 110 of the heat exchanger. In the case where the element 100 is rotationally mobile, the insert also scrapes the walls of the tube and further limits the pressure drop compared to a static insert, as explained in detail below.

[0151] In the case of a static element 100, the first end of the element 100 may be attached to a mechanical link of the fastening system 200, which allows the element 100 to be positioned axially and fixedly within the tube 110 through which a fluid flows. The fastening of the static element 100 in the tube may be reinforced by other means of fastening to the tube, which may be located at a second end opposite the first end and / or along the element 100. The static element 100 may also be secured without dedicated fastening means.

[0152] Preferably, the element 100 is rotationally mobile, and the first end of the element 100 is then fixed to a mechanical link 220 of the fixing system 200 which allows the free rotation of said element 100 on itself around the axis Z of the tube 110 under the action of a fluid passing through said tube 110, as shown in [Fig.6], and said rotationally mobile element 100 having a second free end opposite said first end.

[0153] Advantageously, during its operation in the heat exchanger tube, the presence of element 100 increases the turbulence of the circulating fluid, improves heat exchange, and homogenizes the temperature of the circulating fluid over the entire cross-section of the tube. This prevents the formation of hot spots on the tube wall and consequently significantly reduces the risk of solid deposit formation and improves heat transfer, which is typically hampered by this type of deposit. The insert, when rotated, also scrapes away any deposits that may have formed on the wall, thus reducing fouling. In addition to the reduction of deposits, heat transfer is improved due to the increased turbulence of the circulating fluid caused by the presence of the insert, which enhances convective heat transfer.Indeed, the mere presence of the insert, and even more so its rotation when element 100 is mobile in rotation, allows the creation of turbulence which leads to an increase in heat transfer thanks to the reduction of the thickness of the transfer boundary layer. thermal resistance and thus the transfer resistance near the wall. The heat transfer performance of tubular heat exchangers incorporating such inserts is therefore improved, as is the lifespan of the heat exchangers.

[0154] In the case of a rotating movable element 100, the threshold (threshold speed) for starting rotation of an insert corresponds to the minimum surface velocity of the circulating fluid that allows the rotating element of the insert to begin rotating. The movable element, rotating in the opposite direction to the helical winding of the spring, with a speed that depends on its weight, its geometric characteristics, the flow rate, the viscosity, and the density of the circulating fluid, therefore has its own specific threshold for starting rotation.

[0155] The presence of an insert in the heat exchanger tube induces a pressure drop.

[0156] In the context of the present invention, the inserts of the tubes of the E-2 tubular feed-effluent heat exchanger have the capacity to limit the pressure drop associated with the operation of the insert, and are thus particularly well suited to their use in two-phase tubular heat exchangers that may have more demanding operating conditions with respect to pressure drop, i.e., have a low acceptable pressure drop threshold, as is the case in the field according to the invention. The insert can, in particular, be sized to meet the pressure drop requirements of an existing hydrotreatment or hydroconversion plant.The insert comprising a series of several successions of a first section SI comprising a rigid helical winding of a rod comprising several turns followed by a second section S2 comprising a straight rod, in particular according to the specifications described below, surprisingly improves heat exchange, and possibly reduces fouling, while limiting the pressure loss induced by the insert.

[0157] The pressure loss is further reduced if the element 100 of the insert is mobile in rotation.

[0158] The number of S1 / S2 successions, called n, is determined so as to obtain optimal heat transfer.

[0159] Preferably, n, which is a positive integer, is between 2 and 15, preferably between 2 and 10, more preferably between 4 and 8.

[0160] Preferably, the pitch pl of the first section SI is between 10 mm and 50 mm, preferably is between 20 mm and 40 mm.

[0161] The pitch can be defined in general terms as a function of the angle of inclination of the turns and the diameter of the turns of the rigid helical winding D, according to the following relation: pitch = (ji D) / tana.

[0162] The turn inclination angle a is defined with respect to the winding axis coinciding with the Z axis of the heat exchanger tube in which the insert is mounted. The angle ai refers to the turn inclination angle of the first SI section.

[0163] From one S1 / S2 sequence to another in the chain, the length of a given section (S1, S2) is preferably identical. In this case, the lengths L1 and L2 can be estimated using equations (1) and (2) below: (1) L1 ~ (U / n). (APs / (APi -APv)) where: Lt: the total length of the sequence of S1 / S2 successions (approximately the length of the insert according to the first embodiment), n: the number of S1 / S2 successions of the insert, APs: the maximum additional pressure drop set for one meter of heat exchanger tube, APi: the pressure drop generated for one meter of heat exchanger tube equipped with an insert. APi can be calculated or measured, and the insert used is a classic rigid helical winding of given geometric parameters. APv: the pressure drop generated by one meter of heat exchanger tube without insert.

[0164] Advantageously, the length L2 of the second section can be expressed as follows: (2) L2 = (U / n) - L1 Preferably, the length L1 of the first SI section is between 50 mm and 12000 mm, preferably between 500 mm and 5000 mm.

[0165] Preferably, the length L2 is between 500 mm and 12000 mm, preferably between 500 mm and 5000 mm.

[0166] The first section S1 and the second section S2 are joined together, as are the successions between them, and can form an element 100 in the form of a single piece (a final single piece), typically when permanent joining means such as welds connect the first section S1 and the second section S2 on the one hand, and the successions between them on the other hand.

[0167] The total length of the insert is less than or equal to the total length of the heat exchanger tube 110, and preferably between 50% and 100% of the total length of the heat exchanger tube 110: the total length of the insert is preferably between Lt / 2 and Lt, with Lt being the length of the heat exchanger tube 110.

[0168] The total length of the insert may be slightly less than the tube length in order to take into account possible elongation related to the mechanical stress applied by the fluid and / or thermal expansion.

[0169] The tube 110 of the heat exchanger E-2 can have a total length of between 500 mm and 6000 mm, preferably between 1000 mm and 6000 mm.

[0170] The rigid helical winding of the first section SI has a diameter D, which corresponds to the diameter of the turns of the winding. Advantageously, the diameter D of the turns of the rigid helical winding of the first section SI is greater than or equal to 80% of the diameter Dt of the tube 110 of the heat exchanger, preferably greater than or equal to 90% of the diameter Dt, in order to generate optimal turbulence of the circulating fluid and possibly to scrape deposits on the tube wall efficiently. Preferably, the diameter D of the turns of the rigid helical winding of the first section SI is between 80% and 100% of the diameter Dt of the heat exchanger tube 110, more preferably between 85% and 100% of the diameter Dt. In the case of a rotating element 100, the diameter D of the turns of the rigid helical winding of the first section SI is preferably between 80% and 99% of the diameter Dt of the heat exchanger tube 110, more preferably between 85% and 95% of the diameter Dt.

[0171] The diameter of the tubes (internal diameter Dt) can be between 10 mm and 100 mm, preferably between 10 mm and 50 mm.

[0172] Advantageously, there is a space "c" between the rigid helical winding of section SI and the inner wall of the tube 110 such that said rigid helical winding of the element does not touch the tube wall, in the case of the rotating insert, as referenced in [Fig. 7] showing a rear view of a portion (part of the first section SI) of the insert and the heat exchanger tube E-2, so as not to damage the tube wall, for example, by creating scratches that could form surface irregularities that could promote corrosion. Said space "c" is preferably between 1 mm and 3 mm.

[0173] The rigid helical winding of the SI section can have a cross-section taking different forms, and preferably has a circular or square cross-section, and more preferably has a circular cross-section. In the case of a square cross-section or another shape, the diameter of the cross-section is understood to be an equivalent diameter D_eq, defined as follows: D_eq = 4 * Cross-sectional area / perimeter of the cross-section.

[0174] The rod, preferably metallic, forming the rigid helical winding of section SI has a diameter e1, and the straight rod, preferably metallic, of the second section S2 has a diameter e2. The diameters el and e2 are preferably between 0.5 mm and 5 mm, more preferably between 1 mm and 3 mm. The diameters el and e2 can be identical or different. Having identical diameters el and e2 has the advantage of simplifying the manufacture of the insert.

[0175] The direction of the rigid helical winding of the SI section, which can also be defined as the direction of the pitch of the turns, can be clockwise, or counterclockwise (with respect to the direction of the flow of the fluid in the tube, represented by an arrow along the Z axis in the figures).

[0176] The first end of the element 100, preferably attached to the mechanical link 220, may include a ring la or any other means of attachment to the mechanical link 220.

[0177] The insert material may be carbon steel, stainless steel, or any other metal or metal alloy material such as Inconel®, providing the insert with the required rigidity and preferably resistant to high temperatures and corrosion. The insert material is preferably less hard than the heat exchanger tube material to prevent degradation of the tube.

[0178] For highly corrosive fluids, the material forming the insert can be coated with a layer of a protective material, typically a polymer layer.

[0179] The material forming the insert can alternatively be a polymer or composite material (metal or metal alloy with a polymer material, or different types of polymers, or a composite material combining different types of reinforcements, such as fibers, particles, etc., with different matrices, such as a polymer, metallic or ceramic matrix).

[0180] The rigid helical winding of the first section SI and the straight rod of the second section S2 of the element are robust elements, i.e., whose risk of breakage is low.

[0181] The system for attaching the insert to the tube can be a traditional attachment system, for example, such as that described in patents FR2612267 and FR2639425 in the case of an insert with a rotating movable element 100. In this case, the attachment system is advantageously arranged along the Z-axis of the heat exchanger tube so that the movable element of the insert can rotate about said axis. The attachment system is typically positioned at the inlet of the tube, and the rotating movable element of the insert is connected to the attachment system and positioned downstream in the tube. An example of a traditional attachment system 200 is shown in [Fig. 6], and includes a bearing 230 and the mechanical linkage 220 typically formed by a rotating trunnion. Said trunnion 220 is fixed to the movable element 1 of the insert so that the insert is free to rotate about the Z-axis of the tube 110.The bearing 230 consists of a part 230a in the form of a stirrup, typically a one-piece component made of a rigid material capable of elastic deformation, the end of which is in the form of two arms allowing attachment to the conduit of the tube 110, and a central part 230b consisting of an orifice for retaining the trunnion 220. The two. The arms of the stirrup-shaped portion 230a are separated by a distance such that the arms can be forcibly engaged in an open end of the tube 110 to bear elastically against the inner wall of the tube, thereby making said portion 230a of the bearing 230 rigidly attached to the tube 110. The trunnion 220 consists of a straight cylindrical rod engaged in the opening of the central portion 230b of the bearing 230 and a hook-shaped end 210 that can be hooked onto the ring or any other fastening means included in the first end of the rotating element 100. The other end of the trunnion 220 has a washer-shaped head adapted to hold it captive in the bearing 230. A wear washer may also be interposed between the bearing and the trunnion head.

[0182] The system for attaching the insert to the tube can also be configured so that the element 100 of the insert is fixed, i.e., static, within the insert (no rotation of the insert). Such a fastening system may include various means of attaching the element 100 to the tube, at the inlet and / or inside the tube, and possibly at the outlet of the tube, for example, and without being exhaustive: - a transverse rod respectively at the inlet and outlet of the tube and to which element 100 is connected; - a traditional fastening system similar to that shown in [Fig.6] and described above, but without a bearing and without rotation of the trunnion, - at least one ring outside the tube and larger than the diameter of the tube, connected to element 100. The insert can also be fixed in the tube without a dedicated fixing system, for example in the case where the diameter of the rigid helical winding is equal to the diameter of the tube, due to the stiffness of the helical winding which is in contact with the wall of the tube and fixes the insert in the tube.

[0183] Each insert advantageously includes its own tube fixing system, although a common fixing system shared between the inserts of the other E-2 heat exchanger tubes may be used.

[0184] According to one or more embodiments, as illustrated in [Fig. 8], the rotating element 100 of the insert further comprises a rotating drive piece 300 positioned upstream and connected to the first section SI of the sequence positioned first in the assembly. The rotating drive piece 300 is thus positioned between the fastening system 200 and the first section SI of the first sequence in the assembly of the insert element 100.

[0185] The rotating drive part comprises a shaft 3a coaxial with the helical winding of the first section SI, said shaft being provided with at least two blades 300b attached to the shaft 3a.

[0186] The rotating drive part 300 comprises Nb blades, Nb being an integer between 2 and 6, preferably between 3 and 5.

[0187] Such an insert has the capacity to have a low rotation threshold compared to existing rigid helical-wound rotary inserts. The insert's rotation threshold speed is reduced, thus ensuring a mechanical effect in low fluid flow velocity ranges within the feed-effluent heat exchanger tube, improving the flexibility of use of this type of insert.

[0188] The rotating drive part 300 has a length La, which corresponds substantially to the length of the shaft 3a, and which is preferably between 10 mm and 500 mm, preferably between 20 mm and 200 mm.

[0189] The total length of such an insert is essentially constituted by the sum of the length La of the rotating drive part 300 and the length L of the sequence of successions S1 / S2, the length L! being able to be equal to n times the sum of the lengths L1 and L2 if the lengths L1 and L2 are identical from one succession to the other.

[0190] The length L3 of a blade is the distance, along the Z-axis, between the leading edge of a blade and its trailing edge. The leading and trailing edges follow each other in the direction of fluid flow, with the leading edge initially facing the fluid.

[0191] Each blade has a pitch angle [33, which can be defined between the Z axis and the tangent to the mean camber line of the blade at a given point on the blade. This pitch angle can be variable or fixed with respect to Z and / or r in a cylindrical coordinate system.

[0192] Preferably, all the blades are identical, that is to say they have the same geometric characteristics (length, diameter, thickness, etc.).

[0193] The rotating drive part 300 of the insert is a robust element, i.e., one with a low risk of breakage.

[0194] The material forming the rotating drive part 300 of the rotating mobile element 100 of the insert can be one of those already listed above for the insert, and can be identical or different from the material used for linking the sections S1 / S2.

[0195] The example of insert illustrated in [Fig.8] includes a rotating drive part 300 in the shape of a screw, the blades forming spirals, and the pitch of each blade p3 (pitch of revolution) is between 10 mm and 50 mm, more preferably between 15 mm and 20 mm.

[0196] The pitch of revolution of the blades is advantageously adjusted so as to generate the moment necessary to start the rotation of the insert while respecting the pressure loss constraint.

[0197] Advantageously, the screw-shaped rotating drive piece 300 comprises four identical blades 300b. The blades wind around the shaft 3a along the length of the piece, giving the piece its screw shape. The length L3 of the rotating drive piece 300 is also the length of one blade.

[0198] The number of turns (also called revolution) for the screw-shaped drive part 300 is greater than 1, for example equal to 5 as illustrated in [Fig.8].

[0199] The shaft 3a of the rotating drive part 300 has a diameter da3, preferably between 1 mm and about 50% of the tube's internal diameter, typically between 1 mm and 50 mm, more preferably between 2 mm and 10 mm. The diameter of the shaft 3a influences the fluid passage area, and large values ​​of the diameter da3 increase the fluid's surface velocity. The diameter da3 of the shaft 3a can be constant about the Z-axis, as shown in [Fig. 8]. Alternatively, it can be variable about the Z-axis.

[0200] The blades of the rotating drive component 300 have a diameter dr3, preferably greater than or equal to 80% of the diameter Dt of the heat exchanger tube 110, and more preferably greater than or equal to 90% of the diameter Dt. Preferably, the diameter dr3 of the blades is between 80% and 99% of the diameter Dt of the heat exchanger tube 110, and more preferably between 85% and 95% of the diameter Dt. Advantageously, there is a gap between the tip of the blades of said component 300 and the inner wall of the tube 110, so that the blades do not touch the tube wall, thus preventing damage to the tube wall. This gap is preferably between 1 mm and 3 mm. This gap is preferably constant in the direction of the shaft axis. However, it can vary along said axis, for example decrease, preferably continuously, from the inlet to the outlet of the tube (in the direction of fluid flow in an operating situation of the insert)..

[0201] Preferably, the diameter dr3 of the blades is between 8 mm and 99 mm, preferably between 8.5 mm and 95 mm, more preferably between 8.5 mm and 50 mm, and even more preferably between 10 mm and 25 mm. The diameter of a blade is constant, as shown in [Fig. 8], or may vary in the direction of the shaft axis.

[0202] The blades have a thickness e3, preferably between 0.3 mm and 3 mm. The thickness of the blades must be minimal while still meeting mechanical constraints, in order to reduce the overall size and thus the pressure loss.

[0203] The surface of the blades is the surface formed by the junction between two propeller curves with two diameters of revolution: da3 and dr3.

[0204] The angle of inclination [33 of the blades of the drive part shown in [Fig.6] is constant along Z, and varies with the radius r according to the equation: [33=arctan((2ir * r) / p3), the pitch p3 being constant.

[0205] The shaft 3a and the blades can be a single unit (i.e. manufactured in one piece), or alternatively be separate units fixed to each other for example by welding or any other rigid fastening means allowing the whole to be joined together.

[0206] The rotating drive piece 300 can be connected to the rigid helical winding of the first section SI of the sequence positioned first in the assembly (starting from the inlet of the tube 110) by any means of attachment allowing the joint rotation of said rigid helical winding with the drive piece 300, and thus ultimately of the moving element 100, about itself around the Z-axis under the action of a fluid flowing through the tube 110. For example, the rotating drive piece 300 has an end 3d, opposite the end 3c, which has a hook connected to a ring la carried by the end of the rigid helical winding of the first section SI of the sequence positioned first. The second end of the element 100, at the end of the assembly of the first and second sections SI and S2, is free.Any suitable fastening method other than a hook-and-washer assembly can be used to secure the rotating drive part 300 and the sequence of sections S1 / S2.

[0207] Any other drive part configuration suitable for reducing the rotation threshold of the insert while limiting the pressure loss can be associated with the sequence of element 100 of the insert integrated with the tubular charge-effluent heat exchanger E-2.

[0208] According to one or more embodiments, the installation further comprises at least one additional heat exchanger, different from the tubular charge-effluent heat exchanger E-2, and which may be single-phase or two-phase, comprising a plurality of tubes 110 through which a fluid flows and which are fitted with an insert.

[0209] The insert may be a known prior art insert as illustrated in [Fig.4], or an insert similar to those used in the tubular charge-effluent heat exchanger E-2 as described above, in particular with reference to Figures 5-8.

[0210] Figure 4 illustrates a rotating insert comprising a rigid helical metal winding with a plurality of turns of length L, diameter D, pitch p, and angle of inclination α(a) defined with respect to the central axis of the winding coinciding with the Z-axis of the heat exchanger tube in which the insert is mounted. The metal rod forming the winding has a thickness e. The metal winding has a free end and an end fitted with a ring for attachment to a tube fastening system as described in relation to Figures 5-7. Examples

[0211] The examples below are intended to show some of the advantages of the installation and process according to the invention comprising tubular charge-effluent type heat exchangers incorporating inserts.

[0212] The hydrocarbon filler is a cut having boiling points between 140°C and 375°C and the following characteristics: - Density: 0.855 - Sulfur content (% by weight): 1.2 - Nitrogen content (ppm by weight): 309.

[0213] The installation comprises two trains of 5 E-2 tubular heat exchangers. The tubes are fitted with inserts.

[0214] The installation follows the cold scheme as shown in [Fig.2], detailed below: The hydrocarbon feed 1 is mixed with a hydrogen stream 4 and then the mixture is partially heated by the reaction effluent 8 from the hydrotreating reactor Rl in the tubular feed-effluent heat exchanger trains E-2. The remainder of the heating is provided by the feed furnace Fl which also serves to start up the unit.Once heated, the hydrocarbon feed-hydrogen stream mixture is sent to the hydrotreating reactor RL. The effluent 8 at the outlet of the hydrotreating reactor is partially cooled in the first heat exchanger El which also heats the feed 24 of the separation column Cl, then is cooled in the tubular feed-effluent exchanger trains E-2, and finally cooled via T air condenser AL. A first separation is carried out in the high-pressure cold separator vessel B-2 to recover the gas fraction containing hydrogen 15 which is purified in the amine scrubbing unit C-2, compressed by the compressor Kl, then recycled to the hydrotreating reactor Rl (stream 4) with a make-up of fresh compressed hydrogen (stream 3) by the compressor K-2.The liquid fraction 20 from balloon B-2 is sent to a medium-pressure (lower than that of B-2) cold separator balloon B-4 to recover the liquid fraction sent to the separation column C-1 and to fractionate the products of interest (27, 30).

[0215] Based on the material and energy balances at the end of the cycle (case “End of Run” in English), a part of the process (exchanger E-2, furnace Fl, air condenser Al, hydrogen compressor of recycled and fresh Kl and K-2) is simulated using the Grayson Streed thermodynamic model, in the Aspen simulation software and the Aspen Exchanger Design & Rating (EDR)™ module.

[0216] Three simulation examples are presented below, differing essentially by the gain on the heat transfer coefficient and by the thermal resistance coefficient due to fouling on the tube side which are taken into account.

[0217] The results of these 3 examples are compared to those of the same process in which the tubular heat exchangers do not include inserts (case REF).

[0218] Example 1 (according to the invention):

[0219] In example 1, we consider a gain on the heat transfer coefficient on the tube side of 30%, i.e. a value of 1690 W / m2.K against 1300 W / m2.K for the REF case (bare tubes without inserts).

[0220] In example 1, no effect on fouling is taken into account: the thermal resistance coefficients due to fouling considered in the calculations are 0.0003 m2.K / W on the tube side and 0.0007 m2.K / W on the calender side.

[0221] Example 2 (according to the invention):

[0222] In example 2, we consider both a gain on the heat transfer coefficient and a reduction in fouling related to the presence of the inserts in the tubes.

[0223] The gain on the heat transfer coefficient on the tube side taken into account is 30%, i.e. a value of 1690 W / m2.K, as for example 1.

[0224] The thermal resistance coefficient due to fouling taken into account is 0.0001 m2.K / W on the tube side, and it is 0.0007 m2.K / W on the calender side as in example 1.

[0225] Example 3 (according to the invention):

[0226] In example 3, we consider both a gain on the heat transfer coefficient and a reduction in fouling related to the presence of the inserts in the tubes.

[0227] The gain on the heat transfer coefficient on the tube side taken into account is 50%, i.e. a value of 1950 W / m2.K.

[0228] The thermal resistance coefficient due to fouling taken into account is 0 m2 .K / W on the tube side, and it is 0.0007 m2.K / W on the calender side as in example 1.

[0229] The results of examples 1 to 3 and of the reference case with bare tubes (REF case) are presented in Table 1 below.

[0230] [Tables 1] REF Example 1 (compliant) Example 2 (compliant) Example 3 (compliant) Heat exchangers charge-effluent E-2 Exchanger power kW 79566 80344 81165.2 81567 Overall heat exchange coefficient UW / m2.K 371 406 452.3 480 Outlet temperature charge flow 6 °C 313.34 315.45 317.46 318.84 Outlet temperature e e fluent flux 10 °C 139.73 137.43 135.03 133.86 Charging furnace Fl Outlet temperature f lux 7 °C 360 360 360 360 Consumption savings toe / year - 535.10 1094.20 1376.37 CO2 emission savings tCO2 / year - 1605.3 3282.6 4129.1 Air condenser ur Al Electrical savings kW - 5.9 12.0 15.1 CO2 emission savings tCO2 / year - 34.7 71.0 89.25

[0231] The examples show significant gains in energy consumption and limitation of CO2 emissions generated at the charging furnace and air condenser level.

[0232] According to Example 1, it is possible to limit fuel consumption at furnace Fl by approximately 535 tonnes of oil equivalent (toe) per year, which is equivalent to approximately 1605 tonnes of CO2 avoided per year (-1% compared to the REF case of E-2 heat exchangers without inserts). A saving of 34.7 t of CO2 is also achieved because the effluent 10 exits at a lower temperature and requires less electricity consumption at air condenser AL.

[0233] According to Example 2, a gain in heat transfer and a limitation of fouling are taken into account. When the fouling resistance coefficient is reduced by 66% in addition to a 30% reduction in the heat transfer coefficient on the tube side, fuel consumption in furnace Fl is reduced by approximately 1094 tonnes of oil equivalent per year, which is equivalent to approximately 3283 tonnes of CO2 avoided (-2% compared to the REF case). 71 tonnes of CO2 per year are also avoided at the AL air-cooled condenser

[0234] According to Example 3, when the introduction of inserts completely eliminates fouling on the tube side and the gain in the tube-side heat transfer coefficient is 50%, fuel consumption in furnace Fl is reduced by approximately 1376 tonnes of oil equivalent per year, equivalent to approximately 4129 tonnes of CO2 avoided (-2.5% compared to the REF case). 89 tonnes of CO2 per year are also avoided at the air-cooled condenser AL

[0235] The addition of inserts in the E-2 tubular charge-effluent heat exchangers results in a pressure loss (pressure drop "Delta P") of the order of 8 mbar / m.

[0236] Table 2 below shows the pressure loss in the tubular charge-effluent heat exchangers E-2 and the increase in compressor power Kl required to compensate for this pressure loss.

[0237] [Tables2] Delta P inserts mbar / m 8 Heat exchanger tube length E-2 m 6 Additional Delta P in E-2 exchangers bar 0.48 Delta P in E-2 exchangers of case REF (without inserts) - 3.02 Total Delta P E-2 exchangers with inserts - 3.50 Compressor power Kl of case REF kW 2202 Compressor power Kl with E-2 exchangers equipped with inserts kW 2252 Additional CO2 emissions t / year 0.121

[0238] The installation of inserts in the tubular charge-effluent heat exchangers E-2 results in an additional pressure loss, requiring a 2.3% increase in compressor power Kl, which corresponds to an increase in CO2 emissions of approximately 0.121 t / year. Compared to the gains from reduced fuel consumption in the charge furnace Fl, these emissions are negligible.

Claims

Demands

1. Hydrotreating or hydroconversion installation for a hydrocarbon feedstock, comprising: - at least one tubular feedstock-effluent heat exchanger (E-2) configured to: preheat and send directly the hydrocarbon feedstock mixed with a hydrogen stream to a charging furnace (Fl) of a hydrotreating or hydroconversion reaction section (Rl), and cool a reaction effluent from the hydrotreating or hydroconversion reaction section (Rl), said tubular feedstock-effluent heat exchanger (E-2) comprising a plurality of tubes (110) through which the reaction effluent flows, said tubes comprising an insert; - the charging furnace (Fl) configured to heat and send the preheated hydrocarbon feedstock-hydrogen stream mixture to the hydrotreating or hydroconversion reaction section (Rl);- the hydrotreating or hydroconversion reaction section (Rl) configured to hydrotreat or hydroconvert the hydrocarbon feed and produce the reaction effluent; - a first air-cooled condenser (Al) configured to cool at least a portion of the reaction effluent cooled by said tubular feed-effluent heat exchanger (E-2) before it is sent to a high-pressure cold separator vessel (B-2); - the high-pressure cold separator vessel (B-2) configured to separate at least a portion of the cooled reaction effluent into a first liquid effluent comprising at least a light fraction and a first gaseous effluent comprising hydrogen, and - a separation column (Cl) configured to separate said first liquid effluent comprising at least a light fraction into a bottom liquid and an overhead effluent.

2. Installation according to claim 1, further comprising a medium-pressure cold separator vessel (B-4) configured to separate the first liquid effluent comprising at least a light fraction into a second liquid effluent comprising at least a light fraction sent to the separation column (Cl) and a second gaseous effluent comprising hydrogen.

3. Installation according to claim 2, further comprising: - a first heat exchanger (El) configured to pre-cool the entire reaction effluent (8) before sending it into said tubular charge-effluent heat exchanger (E-2); - a second heat exchanger (E-4) configured to cool the bottom liquid from the separation column (Cl), and to heat and send the second liquid effluent from the medium-pressure cold separator vessel (B-4) to the separation column (Cl) after additional heating in said first heat exchanger (El).

4. Installation according to claim 2, further comprising: - a hot high-pressure separator vessel (Bl) configured to separate the cooled reaction effluent from said tubular charge-effluent heat exchanger (E-2) into a first liquid effluent comprising at least a heavy fraction and a first gaseous effluent comprising a light fraction sent to the cold high-pressure separator vessel (B-2) after cooling in an external flow heat exchanger (E-3) and passing through said first air condenser (Al);- a medium-pressure hot separator (B-3) configured to separate the first liquid effluent comprising at least a heavy fraction into a second liquid effluent comprising at least a heavy fraction sent to the separation column (Cl), and a second gaseous effluent comprising a light fraction sent to said medium-pressure cold separator (B-4) after cooling in a second air condenser (A-2).

5. An installation according to any one of the preceding claims, wherein the tubular feed-outlet heat exchanger (E-2) is provided with a plurality of inserts fixed to the tubes of said feed-outlet heat exchanger, each insert comprising an element (100) having a rigid helical winding of a rod, preferably metallic, comprising several turns, preferably the element (100) comprising: - a series of several successions of a first section (S1) of length L1 having a rigid helical winding of a rod, preferably metallic, comprising several turns and of a second section (S2) of length L2 having a straight rod, preferably metallic, and - a first end connected to a fixing system (200) of said element (100) to an inlet of said tube (110).

6. Installation according to claim 5, wherein the element (100) of the insert is rotationally mobile, said first end of the element (100) being integral with a mechanical link of the fixing system (200), said mechanical link allowing free rotation of said element (100) about itself around the axis (Z) of said tube (110) under the action of the reaction effluent passing through said tube (110), and said rotationally mobile element (100) having a second free end opposite said first end.

7. Installation according to claim 6, wherein the rotating movable element (100) of the insert further comprises a rotating drive piece (300) positioned between the first end of said element (100) and connected to the first section (SI) of the sequence positioned first in the sequence, said rotating drive piece comprising a shaft (3a) coaxial with the helical winding of the first section (SI) and provided with at least two blades (300b) integral with said shaft (3a).

8. Installation according to any one of claims 5 to 7, wherein the insert comprises: - a pitch pl of the helical winding of the first section SI of between 10 mm and 50 mm; - a length L1 of the first section (SI) and a length L2 of the second section (S2) of between 50 mm and 12,000 mm; - a total length of the insert Lt of between 50% and 100% of the total length Lt of the feed-effluent heat exchanger tube, the total length of the tube Lt being between 500 mm and 6,000 mm.

9. A process for hydrotreating or hydroconverting a hydrocarbon feedstock, comprising the following steps: - preheating and directly sending the hydrocarbon feedstock mixed with a hydrogen stream to a charging furnace by means of at least one tubular feedstock-effluent heat exchanger (E-2) comprising a plurality of tubes (110) through which a reaction effluent flows and comprising an insert in at least one of said tubes; - heating and sending the preheated hydrocarbon feedstock-hydrogen stream mixture to a reaction section hydrotreating or hydroconverting (Rl) using the feed furnace (Fl); - hydrotreating or hydroconverting the hydrocarbon feed in the hydrotreating or hydroconverting reaction section (Rl) comprising at least one reactor comprising at least one catalyst comprising at least one element selected from the elements of Group VIII of the periodic table to form the reaction effluent; - cooling the reaction effluent from the hydrotreating or hydroconverting reaction section (Rl) using said tubular feed-effluent heat exchanger (E-2); - lowering the temperature of at least a portion of the reaction effluent from the tubular feed-effluent heat exchanger (E-2) using a first air condenser (Al) before sending it to a high-pressure cold separator vessel (B-2);- to separate said at least a part of the cooled reaction effluent from the first air condenser (Al) in the high-pressure cold separator vessel (B-2) to form a first liquid effluent comprising at least a light fraction and a first gaseous effluent comprising hydrogen; and - to separate the first liquid effluent comprising at least a light fraction in a separation column (Cl) to form at least a bottom liquid and a top effluent.

10. A hydroconversion or hydrotreatment process according to claim 9, wherein the tubular feed-effluent heat exchanger (E-2) is provided with a plurality of inserts fixed to the tubes of said tubular feed-effluent heat exchanger, each insert comprising an element (100) having a rigid helical winding of a rod, preferably metallic, comprising several turns, preferably the element (100) comprising: - a series of several successions of a first section (S1) of length L1 having a rigid helical winding of a rod, preferably metallic, comprising several turns and of a second section (S2) of length L2 having a straight rod, preferably metallic, and - a first end connected to a fixing system (200) of said element (100) to an inlet of said tube (110).

11. A hydroconversion or hydrotreating process according to claim 9 or claim 10, wherein the hydrotreating or hydroconversion of the hydrocarbon feedstock is carried out under at least one of the following operating conditions: - the temperature is between approximately 200°C and approximately 550°C; - the total pressure is between approximately 1 MPa and approximately 38 MPa; - the overall hourly spatial velocity of the liquid feedstock is between approximately 0.05 h⁻¹ and approximately 12 h⁻¹; - the hydrogen flow comprises between approximately 50% and approximately 100% by volume of hydrogen relative to the volume of the hydrogen flowstock; - the amount of hydrogen relative to the liquid hydrocarbon feedstock is between approximately 50 Nm³ / m³ and approximately 5000 Nm³ / m³

12. Hydroconversion or hydrotreating process according to any one of claims 9 to 11, wherein the hydrocarbon feedstock comprises an initial boiling point greater than 120°C.

13. Hydroconversion or hydrotreating process according to any one of claims 9 to 12, wherein the hydrocarbon feedstock is selected from: - feedstocks of fossil origin selected from gas oils, vacuum distillates, atmospheric residues, vacuum residues or Fischer-Tropsch unit effluents, - feedstocks from biomass conversion selected from vegetable, algal, fish, used food oils, fats of vegetable or animal origin, or oils produced from lignocellulosic biomass, - feedstocks from waste conversion selected from pyrolysis oils of plastics, tires or solid recovered fuels, - and mixtures thereof.

14. A hydroconversion or hydrotreating process according to any one of claims 9 to 13, wherein the high-pressure cold separator vessel (B-2) is operated at a pressure lower than the pressure of the hydrotreating or hydroconversion reaction section (R1) and / or wherein the temperature of the high pressure cold separator tank (B-2) is between 20°C and 100°C.

15. A hydroconversion or hydrotreating process according to any one of claims 9 to 14, further comprising the following steps: - pre-cooling all of the reaction effluent from the hydrotreating or hydroconversion reaction section (R1) by means of a first heat exchanger (El) before sending it to the tubular feed-effluent heat exchanger (E-2); - separating said first liquid effluent comprising at least a light fraction from the high-pressure cold separator vessel (B-2) into a medium-pressure cold separator vessel (B-4) to form a second liquid effluent comprising at least a light fraction sent to the separation column (Cl) and a second gaseous effluent comprising hydrogen;- cool the bottom liquid from the separation column (Cl) and heat and send to said separation column (Cl) said second liquid effluent comprising at least a light fraction by means of a second heat exchanger (E-4); - heat said second liquid effluent comprising at least a light fraction from second heat exchanger (E-4) before sending it to said separation column (Cl) by means of said first heat exchanger (El).;

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