Method for the treatment of organic waste

Abstract

The invention relates to a method for hydrotreating a mixture M1 containing at least organic material, the method comprising: a) pressurising the mixture M1 containing at least organic material in order to obtain a mixture stream M1p, b) injecting water at a temperature of at least 374°C into the mixture stream M1p at an angle ranging from 15° to 90° to obtain a stream M2 containing water and organic material, c) introducing the stream M2 into a hydrotreatment reactor, the hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 containing hydrotreated organic material.

Description

ORGANIC WASTE TREATMENT PROCESS TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates to the field of biomass treatment, in particular sludge from sewage treatment plants, food and agri-food waste, manure digestates and agricultural residues. TECHNICAL BACKGROUND

[0002] Hydrothermal treatments for biomass are becoming increasingly common. They require high temperatures. It is therefore essential to control temperatures in order to achieve the desired hydrothermal treatment quality for the biomass.

[0003] Thus, controlling the temperatures and residence times of the process is extremely important to achieve the desired result. Temperatures that are too high or too low, residence times that are too short or too long either do not allow the desired reactions to occur or lead to unwanted side reactions that result in an overall degradation of the desired performance or, worse, in the production of a residue whose treatment costs will be significant.

[0004] In particular, the heating stage of hydrothermal treatments is a major cause of these side reactions due to the long residence time at intermediate temperatures which can lead to the formation of unwanted compounds such as oils, tars or derivatives close to coal. This heating stage is all the longer as the temperatures to be reached are high, in particular when the temperatures to be reached are close to or higher than the temperature of supercritical water.

[0005] Furthermore, in the state of the art, heating is often carried out via a “tube in tube” type exchanger to recover the heat from the flow (or product) leaving the hydrothermal treatment reactor in order to reduce the quantity of heat required for the process. However, in this type of exchanger, the low thermal conduction of the product to be heated leads to a very significant temperature variation inside the product and therefore different process conditions between the different parts of the product leading to unwanted parasitic reactions.

[0006] There is therefore a need to provide a process for hydrotreating a mixture, such as biomass, allowing better heat exchanges and less formation of unwanted compounds such as oils, tars or derivatives close to coal.

[0007] The invention relates to a process for hydrotreating a mixture M1 comprising at least organic matter, said process comprising:

[0008] a) pressurizing the mixture M1 comprising at least organic matter in order to obtain a flow of mixture M1p,

[0009] b) an injection of water at a temperature of at least 374°C into the flow of the mixture M1p with an angle ranging from 15° to 90°C in order to obtain a flow M2 comprising water and organic matter,

[0010] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter.

[0011] According to one embodiment, the water injected in step b) is at a pressure of at least 225 bars, the method then optionally comprising a step of pressurizing the water to a pressure of at least 225 bars.

[0012] According to one embodiment, the mixture M2 is introduced into a static turbulator before being introduced into the hydrotreatment reactor, said static turbulator preferably being chosen from a propeller, blades, one or more elbows, or combinations thereof.

[0013] According to one embodiment, the method further comprises: at least one heat exchange step X1 making it possible to recover heat from the flow M3 to at least partially heat the water intended to be injected in step b), a cooled flow M3' then being obtained, and optionally comprising at least one additional water heating step, downstream of the heat exchange X1 making it possible to heat the water to the temperature of at least 374°C before its injection in step b), and optionally at least one heat exchange step X2 making it possible to recover heat from the flow M3' to heat the mixture M1p upstream of the water injection of step b), a cooled flow M3'' then being obtained.

[0014] According to one embodiment, the method further comprises: at least one step of cooling at least a fraction of the stream M3' or where appropriate of the stream M3'' making it possible to obtain steam and a stream M4 comprising hydrotreated organic matter, and a step of injecting at least a portion of said steam to preheat the mixture M1 upstream of step a) of pressurizing.

[0015] According to one embodiment, the mixture M1 is preheated upstream of step a) of pressurizing to a temperature ranging from 50 to 160°C, preferably from 50 to 90°C.

[0016] Preferably, the cooling of at least a fraction of the flow M3' or where appropriate of at least a fraction of the flow M3'' is carried out at a pressure regulated as a function of the preheating temperature of the mixture M1 upstream of the pressurization step a).

[0017] According to one embodiment, the method further comprises a step of cooling at least a fraction of the M4 stream to obtain a M4' stream and at least one digestion step implemented on at least a fraction of the M4' stream.

[0018] According to one embodiment, the mixture M1p during the water injection of step b) is at a temperature ranging from 90°C to 300°C, preferably from 90 to 170°C.

[0019] According to one embodiment, the method further comprises a step of injecting water at a temperature of at least 374°C directly into the hydrotreatment reactor, said water preferably being at the same temperature and at the same pressure as the water injected during step b).

[0020] Preferably, the M3 stream comprising hydrotreated organic matter is recovered via an outlet in the upper part of the reactor, said reactor further comprising an outlet in the lower part of the reactor.

[0021] Preferably, the stream M3 comprising hydrotreated organic matter leaving the reactor can undergo one or more other subsequent treatment steps, said other step(s) being implemented where appropriate upstream of the heat exchanges X1 and X2.

[0022] The invention also relates to an installation for implementing the hydrotreatment process according to the invention, said installation comprising: a mixture supply line M1, a pressurization pump 2 supplied by the mixture supply line M1 and comprising a mixture outlet line M1p, a water injection device ES with an angle ranging from 15° to 90° into the mixing line M1p downstream of the pressurization pump 2, a flow supply line M2 downstream of the water injection device ES and upstream of the hydrotreatment reactor, a hydrotreatment reactor 1 comprising at least one inlet for introducing at least a fraction of the flow M2 and at least one outlet for extracting a flow M3.

[0023] According to one embodiment, the installation according to the invention further comprises: A static turbulator 10 supplied by the flow M2, said static turbulator being located upstream or at the inlet of the hydrotreatment reactor 1, and a heat exchanger 6 downstream of the hydrotreatment reactor 1, said heat exchanger making it possible to recover the heat from the flow M3 to obtain a flow M3' and to transfer this heat to the water upstream of the water injection device ES, and optionally a water heating device 7, downstream of the heat exchanger 6 and upstream of the water injection device ES.

[0024] According to one embodiment, the installation according to the invention further comprises: Optionally a heat exchanger 8 for recovering heat from the mixture M3' to obtain a mixture M3'' and transferring this heat to the mixture M1p upstream of the water injection device ES, A cooling device 4 supplied by at least a fraction of the flow M3' or, where appropriate, M3'' making it possible to produce steam and a cooled flow M4, A device 3 for injecting said steam produced into the mixture flow M1 upstream of the pressurizing pump 2, Optionally a cooling device 9 downstream of the cooling device 4 supplied by at least a fraction of the flow M4 making it possible to cool at least a fraction of the flow M4 to obtain a flow M4', and Optionally a digester 5 supplied by the flow M4'.

[0025] The invention thus allows the biomass to be heated very quickly by direct heating, which subsequently allows the desired process conditions to be controlled.

[0026] The invention also makes it possible to achieve uniform heating of the biomass, in particular thanks to a static mixer which also allows control of the desired process conditions.

[0027] Finally, the invention makes it possible to maintain the thermal recovery of the process by heating the water in supercritical conditions in order to minimize the overall thermal consumption of the process.

[0028] Biomass has a certain viscosity. However, viscosity makes heat exchange difficult. Since water has a lower viscosity than any other biomass, heating the water will result in a smaller recovery exchanger and therefore a lower cost.

[0029] The invention proposes injecting supercritical water directly into the flow of organic matter M1. Thus, the thermal shock between the organic matter M1, part of which is cellular content, and the very hot supercritical water will cause local cavitations due to the difference in local density and therefore local pressure. These cavitations allow immediate release of the cellular content into the aqueous matrix and therefore, subsequently, in the hydrotreatment reactor, immediate reactions of the proteins and sugars contained in the bacteria. BRIEF DESCRIPTION OF THE FIGURES

[0030] represents an installation according to an embodiment of the method according to the invention.

[0031] represents an installation according to an embodiment of the method according to the invention.

[0032] represents an installation according to an embodiment of the method according to the invention.

[0033] represents an installation according to an embodiment of the method according to the invention.

[0034] represents an installation according to an embodiment of the method according to the invention.

[0035] represents an installation according to an embodiment of the method according to the invention. DETAILED DESCRIPTION OF THE INVENTION

[0036] The invention relates to the hydrothermal treatment of a mixture M1 comprising organic matter. The mixture M1 will further comprise inorganic matter.

[0037] Mixture M1 is typically a biomass. Biomass can be pasty or liquid, and can include sewage sludge, food and agri-food waste, and especially manure digestate and agricultural residues.

[0038] The present invention relates to a method for hydrotreating a mixture M1 comprising at least organic matter, said method comprising:pressurizing the mixture M1 comprising at least organic matter, making it possible to obtain a mixture stream M1p,injecting water at a temperature of at least 374°C into the mixture stream M1p with an angle ranging from 15° to 90° in order to obtain a stream M2 comprising water and organic matter,introducing the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter.

[0039] For the purposes of the present invention, the expression "at least a fraction of a mixture or stream" has the same meaning as the expression "all or part of said mixture or stream". When referring to a part of said mixture or stream, this expression refers to a certain proportion of said mixture or stream. For example, for the purposes of this expression "each fraction of the mixture" or "each fraction of the stream" will have the same composition.

[0040] For the purposes of the present invention, the expression "where appropriate of step X" introduces a characteristic present when step X is present.

[0041] For the purposes of the present invention, the expression “where applicable of the flow X” introduces a characteristic present when the flow X is present. Pressurization step a)

[0042] The method according to the invention comprises a step of pressurizing the mixture M1 to a pressure preferably ranging from 150 to 350 bars, preferably from 170 to 220 bars, said mixture M1 possibly already being under pressure.

[0043] For the pressurization step, a pump can be provided on the M1 mixing line.

[0044] Downstream of the pressurization, a flow of M1p mixture is obtained. Water injection step b)

[0045] The method according to the invention comprises a step during which water at a temperature of at least 374°C is injected into the mixture stream M1p in order to obtain a mixture stream M2 comprising water and organic matter. The mixture M2 will typically also comprise inorganic matter.

[0046] Water injection is implemented at an angle ranging from 15° to 90°, preferably 45 to 90°, or even 45 to 75°, relative to the M1p flow arrival line.

[0047] Illustrates the angle defined in the invention, as being the angle (alpha) between the water injection line ES and the flow arrival line M1p.

[0048] After ES water injection, flow line M2 may not be parallel with flow line M1p. For example, flow line M2 may include a turbulator that would consist of one or more changes in direction of the piping before entering the hydrotreatment reactor.

[0049] According to one embodiment, the mixture M1p during the water injection of step b) is at a temperature ranging from 90°C to 300°C, preferably from 90 to 170°C.

[0050] The M1p mixture can be heated in one or more stages, for example by heat exchange and / or by external heating.

[0051] Upstream of step b), the injected water will typically be at a pressure higher than the pressure of the M1p mixture.

[0052] According to a preferred embodiment of the invention, the water injected in step b) is at a pressure of at least 225 bars. According to this embodiment, the injected water will then be called “supercritical water”.

[0053] According to one embodiment, the method of the invention comprises at least one step of heating the water making it possible to obtain water at a temperature of at least 374°C upstream of its injection in step b).

[0054] According to one embodiment, the method according to the invention comprises a step of pressurizing the water to a pressure of at least 225 bars followed by at least one step of heating the water to obtain water at a temperature of at least 374°C upstream of its injection in step b).

[0055] Preferably, at least one water heating step is implemented by heat exchange with the heat of at least a fraction of the stream M3 comprising hydrotreated organic matter leaving the hydrotreatment reactor, the stream thus cooled will be called stream M3' at the end of this heat exchange (it could be the heat exchange step X1 described below).

[0056] At the outlet of the injection between the ES water and the M1p mud, a static turbulator (e.g. chosen from propeller, blades, pipe bends, or combinations thereof) can also be introduced to increase the turbulence and rapid heat exchange between the mud and the water and to prevent the mud and the water from remaining in separate flows (in order to avoid laminar hydraulic lines).

[0057] Thus, according to one embodiment of the invention, upstream of step c), the mixture M2 is introduced into a static turbulator, said static turbulator then being located upstream of the reactor or at the inlet of the hydrotreatment reactor.

[0058] According to one embodiment, a static turbulator is present upstream or at the inlet of the hydrotreatment reactor in order to increase the turbulence in the mixture M2. Step c)

[0059] The method according to the invention comprises a step of introducing the M2 stream into a hydrotreatment reactor, optionally after passing through a static turbulator.

[0060] The hydrotreatment reactor is advantageously maintained at a temperature ranging from 150°C to 430°C. For example, this temperature maintenance can be carried out via a peripheral heat exchange with a hot fluid, the implementation of the equipment inside a furnace maintained at temperature, the implementation of an electric heating collar.

[0061] In the context of the process of the invention, control of the flow rates of the injected water, preferably supercritical water, and of the M1p mixture is advantageously implemented and will typically allow the new mixture (mixture called M2) to have a residence time in the hydrotreatment reactor ranging from 1 minute to 30 minutes, preferably 10 minutes to 15 minutes.

[0062] At the outlet of the hydrotreatment reactor, a stream comprising hydrotreated organic matter is obtained, stream M3. The process of the invention will typically comprise a step of extracting a stream M3.

[0063] Advantageously, the hydrotreatment reactor consists of an outlet for M5 material, so-called non-hydrotreated material. Indeed, the hydrotreatment reactor can be equipped with a separation device, for example a filter, making it possible to obtain a flow enriched in soluble materials (flow M3) and a flow depleted in soluble materials (flow M5), then to extract them from the reactor.

[0064] For the purposes of the present invention, the term “flow enriched in soluble materials” means a flow comprising a mass proportion of soluble materials greater than the mass proportion of soluble materials in the mixture M2.

[0065] For the purposes of the present invention, the term “flow depleted in soluble materials” means a flow comprising a mass proportion of soluble materials lower than the mass proportion of soluble materials in the mixture M2.

[0066] For the purposes of the present invention, a soluble material will be a material obtained after filtration in a 40 µm filter (material not retained by said 40 µm filter) then drying of an initial material.

[0067] The filter may comprise one or more filtration layers, which may optionally have different mesh sizes, preferably the external filtration layers have mesh sizes larger than the internal filtration layers.

[0068] According to one embodiment, the filter has a mesh size of less than 100 µm, preferably less than 50 µm, more preferably less than 40 µm. When the filter comprises several filtration layers, then the finest mesh will preferably have a size of less than 100 µm, preferably less than 50 µm, more preferably less than 40 µm.

[0069] According to one embodiment, the method of the invention comprises an extraction of a hydrotreated stream M3 (also called a stream enriched in soluble matter) and an extraction of a non-hydrotreated stream M5 (also called a stream depleted in soluble matter). Preferably, according to this embodiment, the mixture inlet M2 is via an inlet E1 of the hydrotreatment reactor, the outlet of the stream M3 is via an outlet S1 of the hydrotreatment reactor and the outlet of the stream M5 is via an outlet S2 of the hydrotreatment reactor. Advantageously, the inlet E1 is located at an altitude lower than the outlet S1 and at an altitude higher than the outlet S2.

[0070] According to a particularly advantageous embodiment, the method of the invention further comprises at least one heat exchange step X1 making it possible to recover heat from the flow M3 (downstream of the heat exchange X1, the cooled flow will be called flow M3') to at least partially heat the water intended to be injected in step b). Typically, according to this embodiment, the method of the invention further comprises at least one water heating step, downstream of said heat exchange X1, making it possible to heat the water to a temperature of at least 374°C before its injection in step b).

[0071] When the method of the invention comprises a heat exchange step X1, said heat exchange step X1 is preferably carried out with water having a pressure of at least 225 bars, it will thus preferably be carried out after a step of pressurizing the water to a pressure of at least 225 bars.

[0072] According to one embodiment, the method of the invention further comprises a heat exchange step X2 making it possible to recover heat from the flow M3 (preferably from the flow M3' when the first heat exchange X1 is present) to heat the mixture M1p upstream of the water injection of step b) of the method. This heat exchange then makes it possible to obtain a cooled flow M3''.

[0073] The M1p flow downstream of the X2 heat exchange could typically have a temperature ranging from 90 to 170°C.

[0074] The M3'' flux can typically have a temperature ranging from 100 to 200°C.

[0075] Preferably, according to this embodiment, the hydrotreatment process according to the invention further comprises: a step of cooling at least a fraction of the stream M3'' making it possible to obtain steam and a stream M4 comprising hydrotreated organic matter, and a step of injecting at least a portion of said steam to preheat the mixture M1 upstream of step a) of pressurizing.

[0076] The cooling step can be implemented using a cooling device chosen from a heat exchanger integrated or not into a rankine, flash, scrubber cycle, preferably using a flash.

[0077] The steam produced during cooling is, according to this embodiment, used to preheat the mixture M1 upstream of step a) of pressurizing.

[0078] Preferably, according to this embodiment, the mixture M1 is preheated upstream of step a) of pressurizing to a temperature ranging from 50 to 160°C, preferably from 50 to 90°C, using the steam resulting from the cooling of at least a fraction of the flow M3''. It should be noted that the mixture M1 may possibly already be under pressure, before step a) defined in the invention, step a) will thus make it possible to increase the pressure of the mixture M1.

[0079] The invention thus allows for better optimization of the viscosity of the biomass undergoing high-pressure treatments. Indeed, the difficulty of pumping at these high pressures requires a minimum viscosity of the biomass to be pumped in order to meet the specifications of very high-pressure pumps.

[0080] By injecting steam into the M1 mixture, all possibilities are used to reduce the viscosity of the biomass to an acceptable value for pumping technologies while minimizing the dilution of the biomass which can cause additional costs in the sizing of downstream equipment (residence time to be respected, etc.).

[0081] According to one embodiment, the cooling of at least a fraction of the flow M3' or where appropriate M3'' is carried out at a pressure regulated as a function of the preheating temperature of the mixture M1 upstream of the pressurization step a).

[0082] Indeed, pressure and temperature are linked for saturated steam. Maintaining a constant pressure makes it possible to control the temperature of the steam and therefore the maximum temperature that can be reached by the product heated by the steam (mixture M1 in the case of the invention).

[0083] For example, the pressure can be maintained between 2 and 10 bars.

[0084] According to one embodiment, the method according to the invention further comprises an additional step of cooling at least a fraction of the M4 stream comprising hydrotreated organic matter to obtain a M4' stream followed by a step of introducing said M4' stream into a digester to enable the digestion of the organic matter contained in the M4' stream.

[0085] The additional cooling step makes it possible, for example, to cool the M4 flow to a temperature less than or equal to 100°C, preferably less than or equal to 60°C, more preferably less than or equal to 40°C.

[0086] According to one embodiment, the cooled M4' stream is then introduced into a digester to undergo a digestion step.

[0087] Digestion can be carried out according to any digestion method known to those skilled in the art.

[0088] According to one embodiment, the treatment method according to the invention comprises at least one anaerobic digestion step carried out on at least a fraction of the M4' flow, preferably the entire M4' flow.

[0089] Anaerobic digestion can be mesophilic or thermophilic.

[0090] When mesophilic digestion is implemented, then the temperature in the digester ranges from 33°C to 37°C and the residence time is 16 to 22 days.

[0091] When thermophilic digestion is implemented, then the temperature in the digester ranges from 55° to 60°C and the residence time is 10 to 12 days.

[0092] Residence time and temperature are two factors influencing the proper degradation of sludge and therefore the optimization of energy production.

[0093] When the flow to be digested is sufficiently liquid, digestion can be of the UASB type and residence times reduced.

[0094] At the end of the digestion stage, biogas is obtained.

[0095] This biogas typically comprises a mixture consisting essentially of methane, carbon dioxide and water. The biogas may optionally comprise other gases, such as hydrogen, oxygen, nitrogen, hydrogen sulfide, but these other gases collectively represent less than 10% by weight of the biogas, of the total weight of the biogas.

[0096] According to one embodiment, the method according to the invention further comprises one or more steps of preheating the mixture M1p, to a temperature ranging for example from 90°C to 300°C, preferably from 90°C to 170°C. At least one preheating step can for example be carried out by heat exchange X2 with the heat present in the stream M3', said stream M3' being obtained after a first heat exchange X1 carried out on the stream M3 comprising hydrotreated organic matter from step c). Such a heat exchange step X2 can be combined with another external heating step to heat the mixture M1p to the desired temperature.

[0097] According to one embodiment, the method according to the invention further comprises a (further) step of injecting ES2 water at a temperature of at least 374°C directly into the hydrotreatment reactor, step called step d).

[0098] Preferably, said water for this other injection directly into the hydrotreatment reactor is at the same temperature and at the same pressure as the water injected during step b) of the process of the invention. According to one embodiment, this water injected ES2 into the reactor is obtained by the same process as that described for the water injected in step b) (advantageously heat exchange X1 then additional heating). This makes it possible to minimize equipment and energy requirements.

[0099] Preferably, ES water and ES2 water are supercritical water (temperature of at least 374°C and pressure of at least 225 bars).

[0100] Typically, according to this embodiment, the hydrotreatment reactor will comprise, in addition to the inlet for introducing the stream M2, a second inlet E2 for introducing the water ES2 (water at a temperature of at least 374°C). Said second inlet E2 is preferably located at the bottom of the reactor. More specifically, if the stream M2 is introduced at an inlet E1 in the upper part of the hydrotreatment reactor, then the water ES2 will preferably be introduced via an inlet E2 in the lower part of the hydrotreatment reactor.

[0101] According to one embodiment, the ES2 water is introduced into the hydrotreatment reactor in the vertical direction, preferably in the direction from bottom to top relative to gravity.

[0102] According to one embodiment, the M3 stream comprising hydrotreated organic matter is recovered via an outlet in the upper part of the reactor, said reactor further comprising an outlet in the lower part of the reactor.

[0103] For the purposes of the present invention, the expression "lower part" is opposed to the expression "upper part". Thus, an exit in the upper part will be located at a higher altitude than the exit in the lower part. Similarly, an exit in the upper part will be located at a higher altitude than an entrance in the lower part.

[0104] According to one embodiment, the step of injecting water directly into the reactor is carried out by an inlet E2 in the lower part of the reactor, while the outlet of the flow M3 will preferably be carried out by an outlet S1 in the upper part of the reactor.

[0105] Thus, according to an embodiment implementing an injection of water ES2 and an extraction of non-hydrotreated material (depleted in soluble materials), then preferably with respect to the hydrotreatment reactor, the inlet E1 of material M2 is located at an altitude lower than the outlet S1 of material M3 and the inlet E1 of material M2 is located at an altitude higher than the outlet S2 of material M5 and higher than the inlet E2 of water ES2. This configuration thus makes it possible to optimize the residence times and to promote the solubilization of the material in the reactor.

[0106] According to one embodiment, at least a fraction of the M3 stream comprising hydrotreated organic matter leaving the reactor is sent to one or more subsequent treatment stages.

[0107] Among the subsequent treatments that can be implemented, mention may be made of an additional heating step, a hydrothermal gasification step. According to this embodiment, the heat exchange(s) (X1, X2) described in the present invention and the digestion described in the invention will be implemented where appropriate, downstream of said subsequent treatments.

[0108] According to one embodiment, the hydrotreatment process of the invention comprises:

[0109] a) pressurizing the mixture M1, said mixture M1 optionally being under pressure, said mixture M1 comprising at least organic matter, in order to obtain a flow of pressurized mixture M1p,

[0110] (b) an injection of water at a temperature of at least 374°C and at a pressure of at least 225 bars into the flow of the mixture M1p with an angle ranging from 45° to 75° in order to obtain a flow M2 comprising water and organic matter,

[0111] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter,

[0112] said method further comprising:a step of pressurizing water to a pressure of at least 225 bars,a heat exchange step X1 downstream of said pressurizing water, making it possible to recover heat from the flow M3 to at least partially heat the water intended to be injected in step b) and, where appropriate, the water ES2 intended to be injected in step d), making it possible to obtain, downstream of the exchange X1, a cooled flow M3' and a flow of heated water W2,an additional heating step implemented on the flow of heated water W2, downstream of said heat exchange X1, making it possible to heat the water W2 to a temperature of at least 374°C before its injection in step b) and, where appropriate, the water ES2 intended to be injected in step d),a heat exchange step X2, downstream of the heat exchange X1,allowing heat to be recovered from the M3' flow to heat the M1p mixture upstream of the water injection of step b) of the process and, where appropriate, the ES2 water intended to be injected in step d), this heat exchange X2 then making it possible to obtain a cooled M3'' flow.,

[0113] According to one embodiment, the hydrotreatment process of the invention comprises:

[0114] a) pressurizing the mixture M1, said mixture M1 optionally being under pressure, said mixture M1 comprising at least organic matter, in order to obtain a flow of pressurized mixture M1p,

[0115] (b) an injection of water at a temperature of at least 374°C and at a pressure of at least 225 bars into the flow of the mixture M1p with an angle ranging from 15° to 90° in order to obtain a flow M2 comprising water and organic matter,

[0116] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter,

[0117] said method further comprising:upstream of step c), a step of introducing the flow M2 into a static turbulator,a step of pressurizing water to a pressure of at least 225 bars,a heat exchange step X1 downstream of said pressurizing water, making it possible to recover heat from the flow M3 to at least partially heat the water intended to be injected in step b) and, where appropriate, the water ES2 intended to be injected in step d), making it possible to obtain, downstream of the exchange X1, a cooled flow M3' and a flow of heated water W2,an additional heating step implemented on the flow of heated water W2, downstream of said heat exchange X1, making it possible to heat the water W2 to a temperature of at least 374°C before its injection in step b),a heat exchange step X2, downstream of the heat exchange X1,allowing heat to be recovered from the M3' flow to heat the M1p mixture upstream of the water injection of step b) of the process and, where appropriate, the ES2 water intended to be injected in step d), this heat exchange X2 then making it possible to obtain a cooled M3'' flow.,

[0118] According to one embodiment, the hydrotreatment process of the invention comprises:

[0119] a) pressurizing the mixture M1, said mixture M1 optionally being under pressure, said mixture M1 comprising at least organic matter, in order to obtain a flow of pressurized mixture M1p,

[0120] (b) an injection of water at a temperature of at least 374°C and at a pressure of at least 225 bars into the flow of the mixture M1p with an angle ranging from 45° to 75° in order to obtain a flow M2 comprising water and organic matter,

[0121] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter,

[0122] said method further comprising:upstream of step c), a step of introducing the flow M2 into a static turbulator,a step of pressurizing water to a pressure of at least 225 bars,a heat exchange step X1 downstream of said pressurizing water, making it possible to recover heat from the flow M3 to at least partially heat the water intended to be injected in step b) and, where appropriate, the water ES2 intended to be injected in step d), making it possible to obtain, downstream of the exchange X1, a cooled flow M3' and a flow of heated water W2,an additional heating step implemented on the flow of heated water W2, downstream of said heat exchange X1, making it possible to heat the water W2 to a temperature of at least 374°C before its injection in step b) and, where appropriate, the water ES2 intended to be injected in step d),a heat exchange step X2, downstream of the heat exchange X1,allowing heat to be recovered from the M3' flow to heat the M1p mixture upstream of the water injection of step b) of the process and, where appropriate, the ES2 water intended to be injected in step d), this heat exchange X2 then making it possible to obtain a cooled M3'' flow.,

[0123] According to one embodiment, the hydrotreatment process of the invention comprises:

[0124] a) pressurizing the mixture M1, said mixture M1 optionally being under pressure, said mixture M1 comprising at least organic matter, in order to obtain a flow of pressurized mixture M1p,

[0125] (b) an injection of water at a temperature of at least 374°C and at a pressure of at least 225 bars into the flow of the mixture M1p with an angle ranging from 45° to 75° in order to obtain a flow M2 comprising water and organic matter,

[0126] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature of at least 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter,

[0127] said method further comprising:a step of pressurizing water to a pressure of at least 225 bars,a heat exchange step X1 downstream of said pressurizing water, making it possible to recover heat from the flow M3 to at least partially heat the water intended to be injected in step b) and, where appropriate, the water ES2 intended to be injected in step d), making it possible to obtain, downstream of the exchange X1, a cooled flow M3' and a flow of heated water W2,an additional heating step implemented on the flow of heated water W2, downstream of said heat exchange X1, making it possible to heat the water W2 to a temperature of at least 374°C before its injection in step b),a heat exchange step X2, downstream of the heat exchange X1, making it possible to recover heat from the flow M3' to heat the mixture M1p upstream of the water injection of step b) of the process and where applicable the ES2 water intended to be injected in step d),this heat exchange X2 then making it possible to obtain a cooled flow M3'', a step of cooling at least a fraction of the flow M3'' making it possible to obtain steam and a flow M4 comprising hydrotreated organic matter, and a step of injecting at least a portion of said steam to preheat the mixture M1 upstream of step a) of pressurizing.,

[0128] According to one embodiment, the hydrotreatment process of the invention comprises:

[0129] a) pressurizing the mixture M1, said mixture M1 optionally being under pressure, said mixture M1 comprising at least organic matter, in order to obtain a flow of pressurized mixture M1p,

[0130] (b) an injection of water at a temperature of at least 374°C and at a pressure of at least 225 bars into the flow of the mixture M1p with an angle ranging from 15° to 90° in order to obtain a flow M2 comprising water and organic matter,

[0131] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter,

[0132] said method further comprising:upstream of step c), a step of introducing the flow M2 into a static turbulator,a step of pressurizing water to a pressure of at least 225 bars,a heat exchange step X1 downstream of said pressurizing water, making it possible to recover heat from the flow M3 to at least partially heat the water W1 intended to be injected in step b) and, where appropriate, the water ES2 intended to be injected in step d), making it possible to obtain, downstream of the exchange X1, a cooled flow M3' and a flow of heated water W2,an additional heating step implemented on the flow of heated water W2, downstream of said heat exchange X1, making it possible to heat the water W2 to a temperature of at least 374°C before its injection in step b) and, where appropriate, the water ES2 intended to be injected in step d),a heat exchange step X2, downstream of heat exchange X1,allowing heat to be recovered from the flow M3' to heat the mixture M1p upstream of the water injection of step b) of the process and, where appropriate, the water ES2 intended to be injected in step d), this heat exchange X2 then making it possible to obtain a cooled flow M3'', a step of cooling at least a fraction of the flow M3'' making it possible to obtain steam and a flow M4 comprising hydrotreated organic matter, and a step of injecting at least a portion of said steam to preheat the mixture M1 upstream of the pressurization step a).,

[0133] According to one embodiment, the hydrotreatment process of the invention comprises:

[0134] a) pressurizing the mixture M1, said mixture M1 optionally being under pressure, said mixture M1 comprising at least organic matter, in order to obtain a flow of pressurized mixture M1p,

[0135] (b) an injection of water at a temperature of at least 374°C and at a pressure of at least 225 bars into the flow of the mixture M1p with an angle ranging from 45° to 75° in order to obtain a flow M2 comprising water and organic matter,

[0136] c) an introduction of the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter,

[0137] said method further comprising:upstream of step c), a step of introducing the flow M2 into a static turbulator,a step of pressurizing water to a pressure of at least 225 bars,a heat exchange step X1 downstream of said pressurizing water, making it possible to recover heat from the flow M3 to at least partially heat the water W1 intended to be injected in step b) and, where appropriate, the water ES2 intended to be injected in step d), making it possible to obtain, downstream of the exchange X1, a cooled flow M3' and a flow of heated water W2,an additional heating step implemented on the flow of heated water W2, downstream of said heat exchange X1, making it possible to heat the water W2 to a temperature of at least 374°C before its injection in step b) and, where appropriate, the water ES2 intended to be injected in step d),a heat exchange step X2, downstream of heat exchange X1,allowing heat to be recovered from the flow M3' to heat the mixture M1p upstream of the water injection of step b) of the process and, where appropriate, the water ES2 intended to be injected in step d), this heat exchange X2 then making it possible to obtain a cooled flow M3'', a step of cooling at least a fraction of the flow M3'' making it possible to obtain steam and a flow M4 comprising hydrotreated organic matter, and a step of injecting at least a portion of said steam to preheat the mixture M1 upstream of the pressurization step a).,

[0138] The invention also relates to an installation for implementing the hydrotreatment process according to the invention.

[0139] The installation according to the invention comprises: a mixture supply line M1, possibly under pressure, a pressurizing pump 2 supplied by the mixture supply line M1 and comprising a mixture outlet line M1p, a water injection device ES with an angle ranging from 15° to 90° in the mixture line M1p downstream of the pressurizing pump 2, a mixture flow M2 is then obtained, a flow supply line M2 downstream of the water injection device ES and upstream of the hydrotreatment reactor, a hydrotreatment reactor 1 comprising at least one inlet E1 and at least one outlet S1 for a flow M3.

[0140] According to one embodiment, the hydrotreatment reactor 1 further comprises at least one outlet S2 for a flow M5 and / or at least one inlet E2 for introducing water directly into the reactor 1. Preferably, the inlet E1 is located at an altitude lower than that of the outlet S1, more preferably the inlet E1 is located at an altitude higher than that of the outlet S2, advantageously, the outlet S1 is at an altitude higher than that of the inlet E2. This configuration makes it possible to improve the residence times and the solubilization of the material in the reactor.

[0141] The drawings illustrate embodiments of installations for implementing the method according to the invention.

[0142] The installation comprises the mixing feed line M1, the pressurization pump 2, the supercritical water feed line ES via an alpha angle in the mixing line M1p downstream of the pressurization pump 2, and the hydrotreatment reactor 1 having an outlet S1 for the stream M3 and an outlet S2 for the non-hydrotreated material M5.

[0143] According to one embodiment, the installation further comprises a static turbulator 10 supplied by the flow line M2, said static turbulator being upstream or at the inlet of the hydrotreatment reactor 1. The mixture leaving the turbulator 10 can thus supply the hydrotreatment reactor 1. This embodiment is illustrated in the set.

[0144] The static turbulator may be chosen from a propeller, blades or elbows or combinations thereof. Thus, for example, the mixing flow supply line M2 located between the water injection device ES and the hydrotreatment reactor 1 may comprise one or more elbows making it possible to provide turbulence, thus improving the exchanges between the water and the sludge.

[0145] As illustrated in , the turbulator 10 may include elbows.

[0146] According to one embodiment, the hydrotreatment reactor 1 comprises a separation device, for example one or more filters.

[0147] The filter may comprise one or more filtration layers, which may optionally have different mesh sizes, preferably the external filtration layers have mesh sizes larger than the internal filtration layers.

[0148] According to one embodiment, the filter has a mesh size of less than 100 µm, preferably less than 50 µm, more preferably less than 40 µm. When the filter comprises several filtration layers, then the finest mesh will preferably have a size of less than 100 µm, preferably less than 50 µm, more preferably less than 40 µm.

[0149] According to an embodiment illustrated on the, the installation further comprises a water injection device ES2 directly into the hydrotreatment reactor, via an inlet E2, preferably in the lower part of the reactor, allowing vertical injection from the bottom to the top.

[0150] Illustrates an embodiment of the method according to the invention. The installation illustrated in shows a heat exchange step X1 via a heat exchanger 6. The heat exchanger 6 makes it possible to recover the heat present in the flow M3 leaving the hydrotreatment reactor 1 to transfer it to the water W1 in order to preheat the water before its injection into the flow M1p.

[0151] According to an embodiment illustrated in the, the installation according to the invention comprises:

[0152] - a heat exchanger 6 downstream of the hydrotreatment reactor, said heat exchanger 6 making it possible to recover the heat from the flow M3 to obtain a cooled flow M3' and to transfer this heat to the water W1 upstream of the water injection device ES to obtain a flow of heated water W2,

[0153] - a water heating device 7, downstream of the heat exchanger 6 and upstream of the water injection device ES, said heating device 7 being supplied by the water W2 and making it possible to obtain water ES at a temperature of at least 374°C.

[0154] According to an embodiment not shown, the installation comprises on the water supply line W1 upstream of the heat exchanger 6, a pressurization pump advantageously making it possible to bring the water to a pressure of at least 225 bars.

[0155] According to an advantageous embodiment when the installation comprises a water injection device ES2, the installation further comprises a water supply line connecting the heat exchanger 6 or where appropriate the heat exchanger 7 to the water injection device ES2.

[0156] Illustrates an embodiment of the method according to the invention. The installation illustrated in includes:

[0157] - a heat exchanger 6 downstream of the hydrotreatment reactor 1, said heat exchanger making it possible to recover the heat from the flow M3 to obtain a flow M3' and to transfer this heat to the water W1 upstream of the heating device 7, making it possible to obtain heated water W2,

[0158] - a water heating device 7, downstream of the heat exchanger 6 supplied by the heated water W2 and upstream of the water injection device ES,

[0159] - a cooling device 4 supplied by at least a fraction of the flow M3' making it possible to produce steam and a cooled flow M4,

[0160] - a device 3 for injecting said steam produced into the mixture flow M1 upstream of the pressurizing pump 2, said injection device 3 possibly being a reactor,

[0161] - a cooling device 9 downstream of the cooling device 4 making it possible to cool at least a fraction of the flow M4 to obtain a flow M4', and

[0162] - a digester 5 fed by the M4' flow.

[0163] Illustrates an embodiment of the method according to the invention. The installation illustrated in includes:

[0164] - a heat exchanger 6 downstream of the hydrotreatment reactor, said heat exchanger making it possible to recover the heat from the flow M3 to obtain a flow M3' and to transfer this heat to the water W1 upstream of the heating device 7, making it possible to obtain heated water W2,

[0165] - a water heating device 7, downstream of the heat exchanger 6 supplied by the heated water W2 and upstream of the water injection device ES,

[0166] - a heat exchanger 8 for recovering heat from the mixture M3' to obtain a mixture M3'' and transferring this heat to the mixture M1p upstream of the water injection device ES,

[0167] - a cooling device 4 supplied by at least a fraction of the flow M3'' making it possible to produce steam and a cooled flow M4,

[0168] - a device 3 for injecting said steam produced into the mixture flow M1 upstream of the pressurizing pump 2, said injection device 3 possibly being a reactor,

[0169] - a cooling device 9 downstream of the cooling device 4 making it possible to cool at least a fraction of the flow M4 to obtain a flow M4', and

[0170] - a digester 5 fed by the M4' flow.

[0171] It differs from the by the presence of a static turbulator 10.

[0172] According to an embodiment not shown in the Figures, the installation according to the invention further comprises at least one post-treatment device supplied by at least a fraction of the flow M3 downstream of the hydrotreatment reactor 1. When the installation further comprises at least one heat exchanger 6, then said post-treatment device is upstream of said heat exchanger 6. Preferably, said post-treatment device is chosen from a complementary heating step, a hydrothermal gasification step.

Claims

A method for hydrotreating a mixture M1 comprising at least organic matter, said method comprising:pressurizing the mixture M1 comprising at least organic matter in order to obtain a mixture stream M1p,injecting water at a temperature of at least 374°C into the mixture stream M1p with an angle ranging from 15° to 90°C in order to obtain a stream M2 comprising water and organic matter,introducing the stream M2 into a hydrotreatment reactor, said hydrotreatment reactor being maintained at a temperature ranging from 150°C to 430°C, in order to obtain a stream M3 comprising hydrotreated organic matter. Hydrotreatment process according to claim 1, in which the water injected in step b) is at a pressure of at least 225 bars, the process then optionally comprising a step of pressurizing the water to a pressure of at least 225 bars. Hydrotreatment process according to claim 1 or 2, wherein the mixture M2 is introduced into a static turbulator before being introduced into the hydrotreatment reactor, said static turbulator preferably being chosen from a propeller, blades, one or more elbows, or combinations thereof. Hydrotreatment process according to any one of claims 1 to 3, further comprising at least one heat exchange step X1 making it possible to recover heat from the flow M3 to at least partially heat the water intended to be injected in step b), a cooled flow M3' then being obtained, and optionally comprising at least one additional water heating step, downstream of the heat exchange X1 making it possible to heat the water to the temperature of at least 374°C before its injection in step b), and optionally at least one heat exchange step X2 making it possible to recover heat from the flow M3' to heat the mixture M1p upstream of the water injection of step b), a cooled flow M3'' then being obtained. Hydrotreatment process according to claim 4, further comprising:at least one step of cooling at least a fraction of the stream M3' or where appropriate of the stream M3'' making it possible to obtain steam and a stream M4 comprising hydrotreated organic matter, anda step of injecting at least a portion of said steam to preheat the mixture M1 upstream of step a) of pressurizing. Hydrotreatment process according to any one of claims 1 to 5, in which the mixture M1 is preheated upstream of step a) of pressurizing to a temperature ranging from 50 to 160°C, preferably from 50 to 90°C. Hydrotreatment process according to claim 5 or 6, in which the cooling of at least a fraction of the flow M3' or where appropriate of at least a fraction of the flow M3'' is carried out at a pressure regulated as a function of the preheating temperature of the mixture M1 upstream of the pressurization step a). Hydrotreatment process according to any one of claims 5 to 7, further comprising a step of cooling at least a fraction of the stream M4 to obtain a stream M4' and at least one digestion step carried out on at least a fraction of the stream M4'. Hydrotreatment process according to any one of claims 1 to 8, wherein the mixture M1p during the water injection of step b) is at a temperature ranging from 90°C to 300°C, preferably from 90 to 170°C. Hydrotreatment process according to any one of claims 1 to 9, further comprising a step of injecting water at a temperature of at least 374°C directly into the hydrotreatment reactor, said water preferably being at the same temperature and pressure as the water injected during step b). Hydrotreatment process according to any one of claims 1 to 10, in which the stream M3 comprising hydrotreated organic matter is recovered via an outlet in the upper part of the reactor, said reactor further comprising an outlet in the lower part of the reactor. Hydrotreatment process according to any one of claims 1 to 11, in which the stream M3 comprising hydrotreated organic matter leaving the reactor can undergo one or more other subsequent treatment steps, said other step(s) being implemented where appropriate upstream of the heat exchanges X1 and X2. Installation for implementing the hydrotreatment process according to any one of claims 1 to 12, said installation comprising: a mixture supply line M1, a pressurization pump (2) supplied by the mixture supply line M1 and comprising a mixture outlet line M1p, a water injection device ES with an angle ranging from 15° to 90° into the mixing line M1p downstream of the pressurization pump (2), a flow supply line M2 downstream of the water injection device ES and upstream of the hydrotreatment reactor, a hydrotreatment reactor (1) comprising at least one inlet for introducing at least a fraction of the flow M2 and at least one outlet for extracting a flow M3. Installation according to the preceding claim, further comprising: A static turbulator (10) supplied by the flow M2, said static turbulator being located upstream or at the inlet of the hydrotreatment reactor (1), and a heat exchanger (6) downstream of the hydrotreatment reactor (1), said heat exchanger making it possible to recover the heat from the flow M3 to obtain a flow M3' and to transfer this heat to the water upstream of the water injection device ES, and optionally a water heating device (7), downstream of the heat exchanger (6) and upstream of the water injection device ES. Installation according to claim 13 or 14, further comprising: Optionally a heat exchanger (8) for recovering heat from the mixture M3' to obtain a mixture M3'' and transferring this heat to the mixture M1p upstream of the water injection device ES, A cooling device (4) supplied by at least a fraction of the flow M3' or, where appropriate, M3'', for producing steam and a cooled flow M4, An injection device (3) for said steam produced in the mixture flow M1 upstream of the pressurization pump (2), Optionally a cooling device (9) downstream of the cooling device (4) supplied by at least a fraction of the flow M4 for cooling at least a fraction of the flow M4 to obtain a flow M4', and Optionally a digester (5) supplied by the flow M4'.

Images