Catalytic hydrogenation reactor and catalytic hydrogenation method for treating biomass raw material with high acid value and high iodine value

Abstract

The invention discloses a catalytic hydrogenation reactor and a catalytic hydrogenation method for treating a biomass raw material with a high acid value and a high iodine value, and belongs to the technical field of oil product hydrogenation. The catalytic hydrogenation reactor comprises a reactor pressure-bearing container, an inner cylinder, an ash discharge port, a feeding assembly, a reaction assembly and a discharging assembly, the inner cylinder is arranged in the reactor pressure-bearing container, the feeding assembly and the reaction assembly are arranged in the inner cylinder, the reaction assembly comprises a ceramic tube bundle internal part, the discharging assembly is arranged above the inner cylinder, and the discharging assembly is arranged above the inner cylinder. The ash discharge port is formed in the center of the bottom of the reactor pressure-bearing container. By arranging the ceramic tube bundle inner part, selective hydrogenation of the high-acid-value and high-iodine-value biomass raw material is realized under the combined action of the solid catalyst and the liquid catalyst, the iodine value is effectively reduced, and coking of the high-iodine-value biomass raw material in the reaction process is avoided; in addition, the acid value is maintained as far as possible while the iodine value is reduced, and the solid catalyst and the catalytic hydrogenation reactor are not corroded, so that the stability of the solid catalyst and the yield of the product are improved.

Description

Technical Field

[0001] The present application relates to a catalytic hydrogenation reactor and a catalytic hydrogenation method for treating high-acid-value and high-iodine-value biomass raw materials, belonging to the technical field of oil hydrogenation. Background Art

[0002] As a renewable energy source, biomass can replace petroleum resources to prepare liquid fuels and chemicals. Oily biomass oils (including natural oils and waste oils) contain a large amount of unsaturated fatty acids and glycerides, and have a high oxygen content, which makes them thermally unstable and have low calorific value. They must be upgraded and modified before they can be converted into high-grade fuels. In the biomass oil upgrading technology, catalytic hydrogenation is a good method. Through catalytic selective hydrogenation, the C=C double bond on the unsaturated fatty acid chain can be converted into a CC single bond. The saturated oil is called hydrogenated oil or hardened oil. On the one hand, the hydrogenation process can improve the antioxidant and thermal stability of oils, improve the color and smell of oils, change the plasticity of oils, obtain suitable physical and chemical properties, and expand the use; on the other hand, hardened oils can be hydrolyzed to prepare high-purity long-chain fatty acids to provide industrial raw materials for downstream. Therefore, oil hydrogenation is an effective means of oil modification and has high economic value.

[0003] However, biomass raw materials with high iodine value have a high degree of unsaturation and are more easily oxidized and rancid, which leads to a higher acid value. The processing of such high acid and iodine value biomass raw materials requires corresponding acid corrosion resistance for process production equipment and catalysts used in the production process.

[0004] The current conventional solid catalysts for catalytic hydrogenation mostly use the catalyst loaded on an alumina carrier. This type of catalyst is not suitable for biomass raw materials with high acid value and high iodine value. When alumina is used as a carrier, it is easy to react with the biomass raw materials with high acid value, causing corrosion of the solid catalyst and affecting its stability. In order to solve the problem of corrosiveness of biomass raw materials with high acid value and high iodine value, alkaline substances are added to neutralize them in the prior art to prevent the high acid value and high iodine value biomass raw materials from corroding metal equipment and solid catalysts. However, the carboxylate produced by this will increase the cost of subsequent treatment.

[0005] In addition, high iodine value biomass raw materials have a high degree of unsaturation and are prone to polymerization at high temperatures, which in turn forms coke. Coking not only damages the raw materials, but also occurs inside the equipment, which increases heat energy consumption and shortens the equipment operation cycle. In severe cases, it can cause overheating and damage to the equipment, making normal production difficult.

[0006] Therefore, due to the unique properties of high acid value and high iodine value biomass raw materials such as high acid value and high degree of unsaturation, higher requirements are placed on equipment, catalysts and processes when catalytically hydrogenating such biomass raw materials. How to achieve catalytic hydrogenation of high acid value and high iodine value biomass raw materials and expand the source of raw materials for biomass hydrogenation to produce green products has always been the direction of technical research in the industry. Summary of the invention

[0007] In order to solve the above problems, the present application proposes a catalytic hydrogenation reactor and a catalytic hydrogenation method for treating high-acid value and high-iodine value biomass raw materials. By providing a catalytic hydrogenation reactor and a catalytic hydrogenation method for treating high-acid value and high-iodine value biomass raw materials, on the one hand, by setting a ceramic tube bundle internal in the catalytic hydrogenation reactor, it can be used as a reaction component, and can also be used as a carrier of a solid catalyst. Under the joint action of a solid catalyst and a liquid catalyst, the selective hydrogenation of high-acid value and high-iodine value biomass raw materials is realized, and the iodine value is effectively reduced, and the formation of coking of high-iodine value biomass raw materials during the reaction is avoided; In addition, the present application reduces the iodine value while maintaining the acid value as much as possible, without corroding the solid catalyst, thereby improving the stability of the solid catalyst and the yield of the product; On the other hand, the catalytic hydrogenation method provided by itself effectively reduces the iodine value, simplifies the process, reduces the reaction temperature, avoids coking during the reaction, and also avoids the high-acid value and high-iodine value biomass raw materials from corroding the catalytic hydrogenation reactor. In general, the method can achieve the reduction of the iodine value while maintaining the acid value as much as possible, without corroding the solid catalyst and the catalytic hydrogenation reactor.

[0008] According to one aspect of the present application, a catalytic hydrogenation reactor for processing high-acid value and high-iodine value biomass raw materials is provided, comprising a reactor pressure vessel, an inner cylinder, an ash discharge port, a feed assembly, a reaction assembly and a discharge assembly, wherein the inner cylinder is arranged inside the reactor pressure vessel, the feed assembly and the reaction assembly are arranged in the inner cylinder, the reaction assembly comprises a ceramic tube bundle internal, the discharge assembly is arranged above the inner cylinder, and the ash discharge port is arranged at the bottom center of the reactor pressure vessel.

[0009] Optionally, the ceramic tube bundle inner part is a truncated cone structure, and a plurality of channels are provided on the ceramic tube bundle inner part, and the channels penetrate the ceramic tube bundle inner part.

[0010] Specifically, a flow guide channel is provided in the center of the ceramic tube bundle inner part, and flow guide plates are provided at both ends of the flow guide channel.

[0011] Specifically, on the one hand, the ceramic tube bundle inner parts serve as reaction components. Under the action of solid catalysts, deep hydrogenation and saturation reaction of double bonds is carried out in the ceramic tube bundle inner parts, thereby reducing the iodine value while maintaining the acid value as much as possible. On the other hand, the ceramic tube bundle inner parts can also serve as carriers of solid catalysts, that is, active metal materials such as molybdenum and / or tungsten are coated on the inner walls of the ceramic tube bundle inner parts to form a solid catalyst. The ceramic tube bundle inner parts, as part of the solid catalyst, are conducive to maintaining the smoothness of the internal channels of the ceramic tube bundle inner parts and avoiding problems such as blockage. At the same time, the ceramic tube bundle inner parts are used as carriers of the solid catalyst. The ceramic tube bundle inner parts are acid-resistant and effectively improve the stability of the solid catalyst.

[0012] Optionally, the feed assembly includes a feed inlet, an annular feed injector and a pre-rectifier; the feed inlet is arranged at the bottom of the reactor pressure container, the annular feed injector is arranged at the bottom of the inner tube, and the feed inlet is communicated with the annular feed injector; the pre-rectifier is connected to the inner wall of the inner tube, and the pre-rectifier is arranged above the annular feed injector to mix and evenly flow to form a plunger flow shape.

[0013] Optionally, the discharge assembly includes a combined baffle, a post-rectifier, an antiscalant bed and a discharge port; the post-rectifier and the antiscalant bed are connected to the inner wall of the reactor pressure container; the antiscalant bed is arranged above the post-rectifier, and the post-rectifier is arranged above the combined baffle.

[0014] Specifically, the antiscalant bed is a packing layer with dense, narrow and tortuous channels to adsorb ash and heavy impurities.

[0015] According to another aspect of the present application, the present application also provides a catalytic hydrogenation method based on the above-mentioned catalytic hydrogenation reactor for treating high-acid value and high-iodine value biomass raw materials, comprising the following steps:

[0016] (1) Pre-treating the biomass raw material with high acid value and high iodine value by centrifugation, filtration, etc. to remove mechanical impurities and clear water to obtain biomass raw material oil;

[0017] (2) mixing hydrogen into biomass feedstock oil to obtain hydrogen-mixed feedstock oil;

[0018] (3) heating the hydrogen-mixed feedstock oil and injecting the liquid catalyst into the hydrogen-mixed feedstock oil under pressure to obtain feed oil;

[0019] (4) After the feed oil enters the catalytic hydrogenation reactor through the feed port, it is sprayed into the inner cylinder through the annular feed injector, and then flows into the ceramic tube bundle internals through the pre-rectifier, and reacts under the action of the solid catalyst to obtain a low iodine value material;

[0020] (5) The low iodine value material reacts in the middle and upper part of the inner cylinder under the action of the liquid catalyst;

[0021] (6) After the reaction, a portion of the material flows out of the inner cylinder, passes through the combined baffle, the post-rectifier and the antiscalant bed, and is discharged from the discharge port; the other portion of the material returns to the lower part of the inner cylinder through the combined baffle, is back-mixed with the subsequent feed oil, and continues the above reaction.

[0022] Optionally, the liquid catalyst is a liquid containing Group VIB and / or Group VIII complex metals; and the solid catalyst is a catalyst containing molybdenum and / or tungsten.

[0023] Specifically, the appearance of liquid catalysts is in various forms such as oil-soluble, water-soluble or mud-like;

[0024] Optionally, the biomass raw material is biological fat or a mixture containing waste biological fat; the biological fat includes plant fat or animal fat.

[0025] Optionally, the acid value of the biomass raw material is greater than 100 mgKOH / g, and the iodine value is greater than 40 g-I2 / 100 g.

[0026] Furthermore, the acid value of the biomass raw material is greater than 100 mgKOH / g, and the iodine value is greater than 80 g-I2 / 100 g.

[0027] Optionally, in step (2), the hydrogen pressure is 2-6 MPa and the temperature is 140-200° C.; in step (3), the amount of liquid catalyst added is 500-2000 ppmw and the pressure is 2-6 MPa.

[0028] According to another aspect of the present application, there is also provided the use of the above-mentioned catalytic hydrogenation reactor for treating high-acid value and high-iodine value biomass raw materials or the above-mentioned catalytic hydrogenation method in preparing renewable fuels; preferably, the renewable fuel includes bio-naphtha, biodiesel or bio-jet fuel.

[0029] The beneficial effects of this application include but are not limited to:

[0030] 1. The catalytic hydrogenation reactor for treating high-acid-value and high-iodine-value biomass raw materials provided by the present application has ceramic tube bundle internals. On the one hand, by setting the ceramic tube bundle internals in the catalytic hydrogenation reactor, it can be used as a reaction component, and can also be used as a carrier of a solid catalyst. Under the joint action of the solid catalyst and the liquid catalyst, the selective hydrogenation of high-acid-value and high-iodine-value biomass raw materials is realized, and the iodine value is effectively reduced, and the formation of coking of high-iodine-value biomass raw materials during the reaction is avoided; In addition, the present application reduces the iodine value while maintaining the acid value as much as possible, without corroding the solid catalyst and the catalytic hydrogenation reactor, thereby improving the stability of the solid catalyst and the yield of the product; On the other hand, the catalytic hydrogenation method provided by itself effectively reduces the iodine value, simplifies the process, reduces the reaction temperature, avoids coking during the reaction, and also avoids the high-acid-value and high-iodine-value biomass raw materials from corroding the catalytic hydrogenation reactor. In general, the method can achieve the reduction of the iodine value while maintaining the acid value as much as possible, without corroding the solid catalyst and the catalytic hydrogenation reactor.

[0031] 2. The catalytic hydrogenation method for treating high-acid value and high-iodine value biomass raw materials provided in the present application. The high-iodine value biomass raw materials have a high degree of unsaturation and are easily polymerized at high temperatures, thereby forming coke, which will damage both the raw materials and equipment. The present application uses a liquid catalyst and a solid catalyst to work together to achieve deep saturation of double bonds at a relatively low reaction temperature, thereby stabilizing the raw materials, effectively reducing the reaction temperature, and avoiding the formation of coke on the high-iodine value biomass raw materials during the reaction.

[0032] 3. The catalytic hydrogenation method for treating high-acid value and high-iodine value biomass raw materials provided in the present application has simple operating steps, adopts a suspended bed reactor instead of a fixed bed reactor, and the liquid catalyst used can be evenly dispersed in the raw material, fully in contact with the raw material, and has a high unit activity. Under mild conditions, the colloid, sulfide, chloride and other impurities in the raw material can be deeply converted, and most of the impurities can be removed while reducing the iodine value of the biomass raw material. Therefore, the catalytic hydrogenation method provided in the present application can be used without complicated pretreatment of the raw material, thereby reducing the operating cost.

[0033] 4. The catalytic hydrogenation method for treating high-acid value and high-iodine value biomass raw materials provided in this application is carried out under ultra-low pressure and low temperature conditions. Compared with the existing oil hydrogenation process, the lower pressure and temperature are conducive to reducing equipment investment and operating costs.

[0034] 5. The catalytic hydrogenation reactor and catalytic hydrogenation method for treating high-acid value and high-iodine value biomass raw materials provided in this application can be applied to the preparation of renewable fuels such as bio-naphtha, biodiesel or bio-jet fuel. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0036] Figure 1 This is a schematic diagram of the front cross-sectional structure of a catalytic hydrogenation reactor for processing high-iodine value biomass feedstock involved in an embodiment of the present application.

[0037] Figure 2 This is a schematic diagram of a front cross-sectional structure of a catalytic hydrogenation reactor for processing high-iodine value biomass feedstock according to another embodiment of the present application.

[0038] List of parts and reference numerals:

[0039] 1. Reactor pressure vessel; 2. Inner tube; 3. Ash discharge port; 4. Ceramic tube bundle internals; 5. Channel; 6. Guide channel; 7. Guide plate; 8. Feed port; 9. Annular feed injector; 10. Pre-rectifier; 11. Combined baffle; 12. Post-rectifier; 13. Antiscalant bed; 14. Discharge port. DETAILED DESCRIPTION

[0040] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0041] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0042] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0043] In addition, in the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0044] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0045] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0046] In the present application, unless otherwise clearly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0047] refer to Figure 1-Figure 2 The embodiment of the present application discloses a catalytic hydrogenation reactor for processing high-iodine value biomass raw materials, including a reactor pressure vessel 1, an inner tube 2, an ash discharge port 3, a feed assembly, a reaction assembly and a discharge assembly. The inner tube 2 is arranged inside the reactor pressure vessel 1, the feed assembly and the reaction assembly are arranged in the inner tube 2, the reaction assembly includes a ceramic tube bundle internal 4, the discharge assembly is arranged above the inner tube 2, and the ash discharge port 3 is arranged at the bottom center of the reactor pressure vessel 1.

[0048] As an implementation manner, the ceramic tube bundle inner part 4 is a truncated cone structure, and a plurality of channels 5 are provided in the ceramic tube bundle inner part 4 , and the channels 5 penetrate the ceramic tube bundle inner part 4 .

[0049] As a specific implementation, a flow guide channel 6 is provided in the center of the ceramic tube bundle inner part 4 , and flow guide plates 7 are provided at both ends of the flow guide channel 6 .

[0050] As an embodiment, the feed assembly includes a feed port 8, an annular feed injector 9 and a pre-rectifier 10; the feed port 8 is arranged at the bottom of the reactor pressure vessel 1, the annular feed injector 9 is arranged at the bottom of the inner tube 2, and the feed port 8 is connected to the annular feed injector 9; the pre-rectifier 10 is connected to the inner wall of the inner tube 2, and the pre-rectifier 10 is arranged above the annular feed injector 9 to mix and evenly flow to form a plunger flow shape.

[0051] As an embodiment, the discharge assembly includes a combined baffle 11, a post-rectifier 12, an antiscalant bed 13 and a discharge port 14; the post-rectifier 12 and the antiscalant bed 13 are connected to the inner wall of the reactor pressure vessel 1; the antiscalant bed 13 is arranged above the post-rectifier 12, and the post-rectifier 12 is arranged above the combined baffle 11.

[0052] Example 1

[0053] A catalytic hydrogenation method of a catalytic hydrogenation reactor for treating high-acid value and high-iodine value biomass raw materials comprises the following steps:

[0054] (1) centrifuging, filtering and other pretreatments of waste oil with an acid value of 100 mgKOH / g and an iodine value of 40 g-I2 / 100 g to remove mechanical impurities and clear water to obtain biomass raw material oil;

[0055] (2) mixing hydrogen into the biomass feedstock oil to obtain a hydrogen-mixed feedstock oil, wherein the hydrogen pressure is 2 MPa and the temperature is 140° C.;

[0056] (3) heating the hydrogenation feed oil, and injecting the liquid catalyst hexadecyl trimethyl ammonium cobalt molybdate under pressure into the hydrogenation feed oil to obtain feed oil, wherein the amount of the liquid catalyst added is 500 ppmw and the pressure is 2 MPa;

[0057] (4) After the feed oil enters the catalytic hydrogenation reactor through the feed port, it is sprayed into the inner cylinder through the annular feed injector, and then flows into the ceramic tube bundle internals coated with Ni-Mo metal active components through the pre-rectifier, where it reacts to obtain a low iodine value material;

[0058] (5) The low iodine value material reacts in the middle and upper part of the inner cylinder under the action of the liquid catalyst;

[0059] (6) After the reaction, a portion of the material flows out of the inner cylinder, passes through the combined baffle, the post-rectifier and the antiscalant bed, and is discharged from the discharge port; the other portion of the material returns to the lower part of the inner cylinder through the combined baffle, is back-mixed with the subsequent feed oil, and continues the above reaction until the reaction is completed.

[0060] Example 2

[0061] A catalytic hydrogenation method of a catalytic hydrogenation reactor for treating high-acid value and high-iodine value biomass raw materials comprises the following steps:

[0062] (1) centrifuging, filtering and other pretreatments are performed on waste oil with an acid value of 150 mgKOH / g and an iodine value of 60 g-I2 / 100 g to remove mechanical impurities and clear water, thereby obtaining biomass raw material oil;

[0063] (2) mixing hydrogen into the biomass feedstock oil to obtain a hydrogen-mixed feedstock oil, wherein the hydrogen pressure is 6 MPa and the temperature is 200° C.;

[0064] (3) heating the hydrogenation feedstock oil, and injecting the liquid catalyst hexadecyltrimethylnickel ammonium molybdate under pressure into the hydrogenation feedstock oil to obtain feed oil, wherein the amount of the liquid catalyst added is 2000 ppmw and the pressure is 6 MPa;

[0065] (4) After the feed oil enters the catalytic hydrogenation reactor through the feed port, it is sprayed into the inner cylinder through the annular feed injector, and then flows into the ceramic tube bundle internals coated with Ni-Mo-W metal active components through the pre-rectifier, where it reacts to obtain a low iodine value material;

[0066] (5) The low iodine value material reacts in the middle and upper part of the inner cylinder under the action of the liquid catalyst;

[0067] (6) After the reaction, a portion of the material flows out of the inner cylinder, passes through the combined baffle, the post-rectifier and the antiscalant bed, and is discharged from the discharge port; the other portion of the material returns to the lower part of the inner cylinder through the combined baffle, is back-mixed with the subsequent feed oil, and continues the above reaction until the reaction is completed.

[0068] Example 3

[0069] A catalytic hydrogenation method of a catalytic hydrogenation reactor for treating high-acid value and high-iodine value biomass raw materials comprises the following steps:

[0070] (1) centrifuging, filtering and other pretreatments of waste oil with an acid value of 200 mgKOH / g and an iodine value of 80 g-I2 / 100 g to remove mechanical impurities and clear water to obtain biomass raw material oil;

[0071] (2) mixing hydrogen into the biomass feedstock oil to obtain a hydrogen-mixed feedstock oil, wherein the hydrogen pressure is 4 MPa and the temperature is 180° C.;

[0072] (3) heating the hydrogenation feed oil, and injecting the liquid catalyst hexadecyltrimethylammonium nickel molybdenum tungstate under pressure into the hydrogenation feed oil to obtain feed oil, wherein the amount of the liquid catalyst added is 1500 ppmw and the pressure is 4 MPa;

[0073] (4) After the feed oil enters the catalytic hydrogenation reactor through the feed port, it is sprayed into the inner cylinder through the annular feed injector, and then flows into the ceramic tube bundle internals coated with Ni-Mo-W metal active components through the pre-rectifier, where it reacts to obtain a low iodine value material;

[0074] (5) The low iodine value material reacts in the middle and upper part of the inner cylinder under the action of the liquid catalyst;

[0075] (6) After the reaction, a portion of the material flows out of the inner cylinder, passes through the combined baffle, the post-rectifier and the antiscalant bed, and is discharged from the discharge port; the other portion of the material returns to the lower part of the inner cylinder through the combined baffle, is back-mixed with the subsequent feed oil, and continues the above reaction until the reaction is completed.

[0076] Comparative Example 1

[0077] The difference between Comparative Example 1 and Example 3 is that the ceramic tube bundle internals are not included and Ni-Mo-W / γ-Al2O3 solid catalyst is used.

[0078] Comparative Example 2

[0079] The difference between Comparative Example 2 and Example 3 is that the amount of the liquid catalyst added is 400 ppmw, and the rest are the same.

[0080] Comparative Example 3

[0081] The difference between Comparative Example 3 and Example 3 is that Ni-Mo-W / γ-Al2O3 solid catalyst is additionally loaded in the channel of the ceramic tube bundle internals, and the rest are the same.

[0082] Comparative Example 4

[0083] The difference between Comparative Example 4 and Example 3 is that the channels of the ceramic tube bundle inner parts are not coated with active metal materials and are made of ceramic material only, and the rest are the same.

[0084] Comparative Example 5

[0085] The difference between Comparative Example 5 and Example 3 is that the acid value of the waste oil is 50 mgKOH / g, the iodine value is 40 g-I2 / 100 g, and the rest are the same.

[0086] Comparative Example 6

[0087] The difference between Comparative Example 6 and Example 3 is that a fixed bed reactor is used, and the rest is the same.

[0088] Example 1

[0089] The acid value, iodine value, etc. of the hydrogenated oil products of Examples 1 to 3 and Comparative Examples 1 to 6 were measured. The results are shown in Table 1:

[0090] Table 1 Measurement results

[0091]

[0092]

[0093] According to Table 1, it can be concluded that Examples 1 to 3 respectively process biomass raw materials with different initial acid values ​​and iodine values, and the processed raw materials perform well in terms of acid value, iodine value and yield, among which the raw materials with high acid value and high iodine value in Example 3 have the best comprehensive effect.

[0094] Comparative Example 1 does not include the ceramic tube bundle internal structure, and uses Ni-Mo-W / γ-Al2O3 solid catalyst. Compared with Example 3, the acid value after treatment decreases significantly, and the iodine value after catalytic hydrogenation is higher. The reason for the analysis is that the free fatty acid will interact with the liquid catalyst during the reaction, and then preferentially adsorb on the catalyst surface, so that the rate of fatty acid hydrogenation is higher than the double bond saturation reaction rate, resulting in a more obvious decrease in acid value, while the iodine value decreases less. Compared with Example 3, Comparative Example 2 reduces the amount of liquid catalyst added, and the iodine value after catalytic hydrogenation increases compared with Example 3. The reason for the analysis is that the reduction of liquid catalyst reduces the number of catalytic active centers and inhibits the occurrence of hydrogenation reaction. In Comparative Example 3, solid catalyst is additionally loaded in the ceramic tube bundle internal channel, and its iodine value after catalytic hydrogenation increases compared with Example 3. The reason for the analysis is that as the reaction proceeds, the liquid catalyst will be enriched on the surface of the solid catalyst particles, thereby affecting the mass transfer and diffusion of the raw materials in the reactor and the catalyst bed, and affecting the progress of the hydrogenation reaction. In comparative example 4, the ceramic tube bundle inner channel is not coated with active metal materials, but only ceramic materials. The iodine value after catalytic hydrogenation is increased compared with that in Example 3. The reason for the analysis is that the hydrogenation performance of the liquid catalyst alone is low, and it is difficult to achieve deep saturation of carbon-carbon double bonds. In comparative example 5, the initial iodine value and acid value of the waste oil are greatly reduced compared with Example 3, and the effect of reducing the iodine value is worse. The reason for the analysis is that the reduction of free fatty acids and double bonds in the raw material will reduce the collision probability between the raw material molecules and the catalyst, thereby slowing down the hydrogenation reaction rate; at the same time, the lower raw material concentration will form a concentration gradient in the reactor, affecting the reaction. The catalytic hydrogenation method provided in this application is particularly suitable for biomass raw materials with high acid value and high iodine value. In comparative example 6, a fixed bed reactor is used, and the acid value decreases significantly after the reaction, and the iodine value decreases lower than that in Example 3. The reason for the analysis is that as the reaction proceeds, the fixed bed hydrogenation catalyst will gradually lose activity due to the deposition of impurities in the waste oil, especially affecting the adsorption and activation of the C=C double bond, resulting in differences in the hydrogenation reaction rates of the carboxyl group and the double bond, and the reduction in acid value will lead to a decrease in product yield.

[0095] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0096] The above is only an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A catalytic hydrogenation reactor for treating high acid value and high iodine value biomass raw materials, characterized in that: It includes a reactor pressure vessel, an inner tube, an ash discharge port, a feed assembly, a reaction assembly and a discharge assembly. The inner tube is arranged inside the reactor pressure vessel, the feed assembly and the reaction assembly are arranged in the inner tube, the reaction assembly includes a ceramic tube bundle internal, the discharge assembly is arranged above the inner tube, and the ash discharge port is arranged at the center of the bottom of the reactor pressure vessel.

2. The catalytic hydrogenation reactor for treating high acid value and high iodine value biomass raw materials according to claim 1, characterized in that: The ceramic tube bundle inner part is a truncated cone structure, and a plurality of channels are arranged in the ceramic tube bundle inner part, and the channels penetrate through the ceramic tube bundle inner part.

3. The catalytic hydrogenation reactor for processing high acid value and high iodine value biomass raw materials according to claim 2, characterized in that: The feed assembly includes a feed port, an annular feed injector and a pre-rectifier; the feed port is arranged at the bottom of the reactor pressure container, the annular feed injector is arranged at the bottom of the inner tube, and the feed port is communicated with the annular feed injector; the pre-rectifier is connected to the inner wall of the inner tube, and the pre-rectifier is arranged above the annular feed injector to mix and evenly flow to form a plunger flow shape.

4. The catalytic hydrogenation reactor for treating high acid value and high iodine value biomass raw materials according to claim 3, characterized in that: The discharge assembly includes a combined baffle, a post-rectifier, an antiscalant bed and a discharge port; the post-rectifier and the antiscalant bed are connected to the inner wall of the reactor pressure container; the antiscalant bed is arranged above the post-rectifier, and the post-rectifier is arranged above the combined baffle.

5. A catalytic hydrogenation method using a catalytic hydrogenation reactor for treating high-acid-value and high-iodine-value biomass raw materials according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Pre-treating the biomass raw material with high acid value and high iodine value by centrifugation, filtration, etc. to remove mechanical impurities and clear water to obtain biomass raw material oil; (2) mixing hydrogen into biomass feedstock oil to obtain hydrogen-mixed feedstock oil; (3) heating the hydrogen-mixed feedstock oil and injecting the liquid catalyst into the hydrogen-mixed feedstock oil under pressure to obtain feed oil; (4) After the feed oil enters the catalytic hydrogenation reactor through the feed port, it is sprayed into the inner cylinder through the annular feed injector, and then flows into the ceramic tube bundle internals through the pre-rectifier, and reacts under the action of the solid catalyst to obtain a low iodine value material; (5) The low iodine value material reacts in the middle and upper part of the inner cylinder under the action of the liquid catalyst; (6) After the reaction, a portion of the material flows out of the inner cylinder, passes through the combined baffle, the post-rectifier and the antiscalant bed, and is discharged from the discharge port; the other portion of the material returns to the lower part of the inner cylinder through the combined baffle, is back-mixed with the subsequent feed oil, and continues the above reaction.

6. The catalytic hydrogenation method according to claim 5, characterized in that: The liquid catalyst is a liquid containing a Group VIB and / or Group VIII complex metal; the solid catalyst is a catalyst containing molybdenum and / or tungsten.

7. The catalytic hydrogenation method according to claim 5, characterized in that: The biomass raw material is biological fat or a mixture containing waste biological fat; the biological fat includes plant fat or animal fat.

8. The catalytic hydrogenation method according to claim 7, characterized in that: The acid value of the biomass raw material is greater than 100 mgKOH / g, and the iodine value is greater than 40 g-I2 / 100 g.

9. The catalytic hydrogenation method according to claim 5, characterized in that: In step (2), the hydrogen pressure is 2-6 MPa and the temperature is 140-200° C.; in step (3), the amount of liquid catalyst added is 500-2000 ppmw and the pressure is 2-6 MPa.

10. Use of the catalytic hydrogenation reactor for treating high-acid value and high-iodine value biomass feedstock according to any one of claims 1 to 4 or the catalytic hydrogenation method according to any one of claims 5 to 9 in preparing renewable fuel; preferably, the renewable fuel includes bio-naphtha, biodiesel or bio-jet fuel.

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