A serial stage hydrogenation reaction system with catalysts replaceable on line

Abstract

The application provides a catalyst-replaceable series-section hydrogenation reaction system, characterized in that the series-section hydrogenation reaction system comprises: a heating furnace for filling and heating circulating oil; M (M>=2) reaction sections connected in series, the inlet of the first reaction section is connected with the outlet of the heating furnace, and the preheated circulating oil is transported from the (N-1)th reaction section to the Nth reaction section; a separator is provided with a feeding port for adding raw materials, the inlet of the separator is connected with the outlet of the Mth reaction section, and the outlet of the separator is connected with the inlets of the reaction sections respectively; wherein, a catalyst loading device is arranged above the reaction section, and a catalyst unloading device is arranged below the reaction section. The application solves the technical problem that the replacement of the catalyst in the prior art often requires the shutdown operation of the whole system, resulting in the interruption of the chain reaction of the series-section hydrogenation system and the increase of the system energy consumption.

Description

Technical Field

[0001] This utility model relates to the field of hydrogenation technology, and more specifically, to a tandem hydrogenation reaction system with an online catalyst replacement capability. Background Technology

[0002] In the petrochemical industry, hydrotreating systems are widely used to process crude oil, coal tar, or other hydrocarbon feedstocks. Through catalysts, hydrocracking, desulfurization, and denitrification reactions are carried out under high temperature and high pressure conditions to improve product quality. Traditional tandem hydrotreating systems typically employ a multi-stage reaction stage design. Feedstock and circulating oil are heated in a furnace and then sequentially pass through each reaction stage for reaction, ultimately separating the products via a separator.

[0003] However, the relevant technologies have at least one of the following problems: In the prior art, the replacement of catalysts often requires the entire system to be shut down, which leads to the interruption of the chain reaction in the tandem hydrogenation reaction system and increases the system energy consumption. Utility Model Content

[0004] The technical problem solved by this invention is that in the prior art, the replacement of catalysts often requires the entire system to be shut down, which leads to the interruption of the chain reaction in the tandem hydrogenation reaction system and increases the system energy consumption.

[0005] To address the aforementioned problems, this utility model provides a tandem hydrogenation reaction system with online catalyst replacement. The system comprises: a heater for filling and heating circulating oil; M reaction sections (M≥2), connected in series, with the inlet of the first reaction section connected to the outlet of the heater, and preheated circulating oil supplied from the (N-1)th reaction section to the Nth reaction section; a separator with an inlet for adding raw materials, the inlet of which is connected to the outlet of the Mth reaction section, and the outlet of which is connected to the inlet of each reaction section; wherein a catalyst loading device is located above the reaction sections, and a catalyst unloading device is located below the reaction sections for replacing the catalyst within the reaction sections.

[0006] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: After the raw materials enter the N-1th reaction section through the separator, they react and generate heat before entering the Nth reaction section to react with the raw materials again, thus forming a chain reaction between the reaction sections. This reduces the total energy consumption of the entire system. Furthermore, the catalyst loading device and catalyst unloading device work together with the tandem hydrogenation reaction system to allow the catalyst to be replaced online without interrupting the chain reaction, further reducing the total energy consumption.

[0007] In one embodiment of this invention, the tandem hydrogenation reaction system further includes: multiple first flow lines, the two ends of which are respectively connected to the inlet of the reaction section and the outlet of the separator.

[0008] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: by setting up a first flow pipeline in the tandem hydrogenation reaction system, the separator can form a circulation system with each reaction section, thereby enabling the raw materials to enter each reaction section and react with the reactants in the previous reaction section, thus reducing the total energy consumption of the system.

[0009] In one embodiment of this invention, the catalyst tandem hydrogenation reaction system further includes: a plurality of first regulating valves, which are disposed on a first flow pipeline to regulate the feedstock entering each of the reaction sections.

[0010] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: by setting a first regulating valve, dynamic adjustment of raw material and circulating oil flow can be realized, enhancing the system's adaptability to different operating conditions.

[0011] In one embodiment of this utility model, multiple reaction sections constitute a reactor, and the multiple reaction sections are stacked, with the height of the Nth reaction section being lower than that of the (N-1)th reaction section; and / or the inlet of the (N-1)th reaction section and the outlet of the Nth reaction section are connected through a second flow pipeline, so that the (N-1)th reaction section and the Nth reaction section are arranged side by side.

[0012] Compared with existing technologies, the technical effects achieved by adopting this technical solution are: to form a series effect by stacking reaction sections or to set the reaction sections in parallel; to provide flexible reaction section configuration to adapt to different process requirements and enhance the modularity and scalability of the system.

[0013] In one embodiment of this invention, when multiple reaction sections are stacked, the catalyst loading device is located at the inlet of the uppermost reaction section, and the catalyst unloading device is located at the outlet of the lowermost reaction section, so that the catalysts of multiple reaction sections can be replaced online.

[0014] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: by setting a catalyst loading device at the upper inlet, the catalyst can be added directly through the catalyst loading device after a reaction cycle is completed, without having to stop the machine to replace the catalyst.

[0015] In one embodiment of this utility model, the separator is connected to the heating furnace via a third flow pipeline, and a second regulating valve is provided on the third flow pipeline to regulate the raw materials entering the heating furnace.

[0016] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: by setting a third flow pipeline between the separator and the inlet of the heating furnace, and controlling the raw materials entering the heating furnace through a second regulating valve, the overall energy utilization can be further improved.

[0017] In one embodiment of this invention, the reaction temperature within the reaction section is 260° to 400°.

[0018] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: by setting a precise temperature range to optimize the hydrogenation reaction conditions, the balance between catalyst activity and reaction efficiency is ensured, thereby improving the yield and quality of the target product.

[0019] In one embodiment of this invention, the ratio of raw materials to circulating oil in each reaction section is 0.3 to 3.

[0020] Compared with existing technologies, the technical effect achieved by adopting this technical solution is that by adjusting the ratio of raw materials to circulating oil in each reaction section, the reaction efficiency of the entire system can be dynamically improved according to the operating conditions.

[0021] In one embodiment of this utility model, the reaction section is one of the following: a fluidized bed, a fixed bed, a moving bed, a radial bed, an expanded bed, and a suspended bed.

[0022] Compared with existing technologies, the technical effects achieved by adopting this technical solution are: by setting up multiple reaction section types, the system's adaptability to different hydrogenation processes is enhanced.

[0023] In one embodiment of this invention, the catalyst in the reaction section is a catalyst with good water stability.

[0024] Compared with existing technologies, the technical effects achieved by adopting this technical solution are as follows: using a catalyst with good water stability as the core material in the reaction section can significantly improve the stability and economy of the overall process. This is because such a catalyst is not prone to hydrolysis or deactivation of active sites when faced with the introduction of water or water vapor environment during hydrogenation, thereby extending its service life and reducing the frequency of replacement.

[0025] By adopting the technical solution of this utility model, the following technical effects can be achieved: (1) After the raw material enters the N-1 reaction section through the separator, it reacts and generates heat before entering the N reaction section to react with the raw material again, so that the reaction sections form a chain reaction, reducing the total energy consumption of the entire system. In addition, the catalyst loading device and the catalyst unloading device work together with the tandem hydrogenation reaction system to allow the catalyst to be replaced online. The chain reaction will not be interrupted when the catalyst is replaced, further reducing the total energy consumption. (2) By setting the first regulating valve, the flow rate of raw materials and circulating oil can be dynamically adjusted, thereby enhancing the system's adaptability to different working conditions; (3) The reaction sections are stacked to form a series effect, or the reaction sections are set in parallel; the reaction section configuration is flexible to adapt to different process requirements and enhance the modularity and scalability of the system. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Figure 1 This is a schematic diagram of a tandem hydrogenation reaction system provided in an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached figures: 1. Feed inlet; 2. Separator; 3. Heating furnace; 4. Reaction section; 5. Hydrogen inlet; 6. First flow line; 7. First regulating valve; 8. Second flow line; 9. Third flow line; 10. Second regulating valve; 11. Catalyst loading device; 12. Catalyst unloading device; 13. Discharge outlet. Detailed Implementation

[0028] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0029] In existing hydrogen production processes, waste oils such as biomass tar, kitchen oil, swill oil, and gutter oil, as well as low-temperature pyrolysis coal tar, which have high oxygen content, are used for hydrogenation to produce oil products. Waste oils, in particular, have a high oxygen content, generally above 10% (compared to around 1% in crude oil). The hydrogenation reaction is exothermic, resulting in a large temperature increase and the production of a large amount of water. Waste oils also contain high levels of metals, phospholipids, and unsaponifiable matter, which are harmful to the hydrogenation catalyst. Rancid waste oils have a high fatty acid content, and due to the addition of salt during food processing, the raw materials also contain chlorides, causing severe corrosion to the equipment. Existing technologies suffer from severe corrosion of equipment such as heating furnace 3 and reaction section 4, poor catalyst water stability leading to pulverization causing reaction bed blockage, short catalyst life, high energy consumption, and frequent shutdowns for catalyst replacement due to short operating cycles.

[0030] To address the aforementioned problems, this invention provides a tandem hydrogenation reaction system with an online catalyst replacement capability, as described above. Figure 1The tandem hydrogenation reaction system includes a heater 3, a reaction section 4, and a separator 2. The heater 3 is used to fill and heat the circulating oil; M≥2, the reaction sections 4 are connected in series, the inlet of the first reaction section 4 is connected to the outlet of the heater 3, and the preheated circulating oil is transported from the (N-1)th reaction section 4 to the Nth reaction section 4; the separator 2 is provided with a feed inlet 1 for adding raw materials, the inlet of the separator 2 is connected to the outlet of the Mth reaction section 4, and the outlet of the separator 2 is connected to the inlet of each reaction section 4; wherein, a catalyst loading device 11 is provided above the reaction section 4, and a catalyst unloading device 12 is provided below the reaction section 4 to replace the catalyst in the reaction section 4.

[0031] After the raw material enters the N-1th reaction section 4 through the separator 2, it reacts and generates heat before entering the Nth reaction section 4 to react with the raw material again. This creates a chain reaction between the reaction sections 4, reducing the total energy consumption of the entire system. Furthermore, the catalyst loading device 11 and the catalyst unloading device 12 work together in the tandem hydrogenation reaction system to allow the catalyst to be replaced online without interrupting the chain reaction, further reducing the total energy consumption.

[0032] Preferably, the separator 2 is used for refining, fractionation and waste heat recovery, and the separator 2 is also provided with a discharge port 13 for discharging the product.

[0033] Preferably, each reaction section 4 and the heating furnace 3 are also provided with a hydrogen inlet 5 so that hydrogen can react with circulating oil and raw materials.

[0034] Preferably, the raw materials include at least one of waste oils such as biomass tar, kitchen oil, swill oil, and gutter oil.

[0035] Preferably, the number of reaction sections 4 is set according to the operating conditions; in this embodiment, the number of sections is 5.

[0036] Preferably, a dechlorinating agent is installed in the low-temperature mixing zone of the reactor to absorb and remove the hydrogen chloride produced by the reaction.

[0037] Furthermore, the tandem hydrogenation reaction system also includes: multiple first flow lines 6, with both ends of the first flow lines 6 connected to the inlet of the reaction section 4 and the outlet of the separator 2, respectively.

[0038] By setting up a first flow line 6 in the tandem hydrogenation reaction system, the separator 2 can form a circulation system with each reaction section 4, thereby enabling the raw materials to enter each reaction section 4 and react with the reactants of the previous reaction section 4, reducing the total energy consumption of the system.

[0039] Preferably, the front ends of the multiple first flow lines 6 can be merged, so that the raw material passes through one flow line and then through multiple first flow lines 6 into each reaction section 4.

[0040] Furthermore, the catalyst cascade hydrogenation reaction system also includes: multiple first regulating valves 7, which are disposed on the first flow line 6 to regulate the feedstock entering each of the reaction sections 4.

[0041] By setting the first regulating valve 7, the flow rate of raw materials and circulating oil can be dynamically adjusted, thereby enhancing the system's adaptability to different operating conditions.

[0042] Preferably, the first regulating valve 7 is used to regulate the amount of raw material entering each reaction section 4 through the first flow pipeline 6, thereby regulating the ratio of raw material to circulating oil.

[0043] Furthermore, multiple reaction sections 4 constitute a reactor. The multiple reaction sections 4 are stacked, and the height of the Nth reaction section 4 is lower than that of the (N-1)th reaction section 4; and / or the inlet of the (N-1)th reaction section 4 and the outlet of the Nth reaction section 4 are connected through a second flow line 8, so that the (N-1)th reaction section 4 and the Nth reaction section 4 are arranged side by side.

[0044] The reaction section 4 can be stacked to form a series effect, or the reaction section 4 can be set up in parallel; this provides a flexible configuration of the reaction section 4 to adapt to different process requirements and enhance the modularity and scalability of the system.

[0045] Furthermore, in the case of multiple reaction sections 4 stacked together, the catalyst loading device 11 is located at the inlet of the uppermost reaction section 4, and the catalyst unloading device 12 is located at the outlet of the lowermost reaction section 4, so that the catalyst of multiple reaction sections 4 can be replaced online.

[0046] By installing a catalyst loading device 11 at the upper inlet, the catalyst in the reaction section 4 can be added directly through the catalyst loading device 11 after a reaction cycle is completed, without having to stop the machine to replace the catalyst.

[0047] Preferably, the catalyst loading device 11 and the catalyst unloading device 12 are disposed above and below each reactor; for example, in the embodiments of this application, the first to third reaction sections 4 constitute the first reactor, the fourth to fifth reactor constitute the second reactor, the catalyst loading device 11 is disposed above the first reactor and the catalyst unloading device 12 is disposed below the first reactor and the second reactor.

[0048] Furthermore, the separator 2 is connected to the heating furnace 3 via a third flow line 9, which is equipped with a second regulating valve 10 to regulate the raw materials entering the heating furnace 3. By setting a third flow line 9 between the separator 2 and the inlet of the heating furnace 3, and controlling the raw materials entering the heating furnace 3 through the second regulating valve 10, the overall energy utilization can be further improved.

[0049] Furthermore, the reaction temperature within reaction section 4 is between 260°C and 400°C. By setting a precise temperature range to optimize the hydrogenation reaction conditions, a balance between catalyst activity and reaction efficiency is ensured, thereby improving the yield and quality of the target product.

[0050] Preferably, after heating reaction section 4 to 270-450°C, the heated return oil is mixed with the raw material, with the mixing temperature controlled between 220-300°C, and then enters the first-stage reactor. After the first-stage reaction, the outlet temperature is 330-500°C. The heat generated by the first-stage hydrogenation is used as a heat source to mix with the second-stage feedstock, with the mixing temperature controlled between 250-300°C, and then enters the second-stage reactor. This process is repeated to establish a multi-stage tandem hydrogenation reaction system.

[0051] Furthermore, the ratio of raw material to circulating oil in each reaction section 4 is between 0.3 and 3. By adjusting the ratio of raw material to circulating oil in each reaction section 4, the reaction efficiency of the entire system can be dynamically improved according to the operating conditions.

[0052] Preferably, the ratio of raw material to circulating oil at the inlet of each reaction section 4 is between 0.3 and 3, more preferably between 0.8 and 1.5, and even more preferably 1:1. Other ratios that can meet the requirements of heat and reaction balance are within the scope of protection of this patent.

[0053] Furthermore, reaction section 4 can be one of the following: fluidized bed, fixed bed, moving bed, radial bed, expanded bed, or suspended bed. By setting multiple types of reaction section 4, the system's adaptability to different hydrogenation processes is enhanced.

[0054] Preferably, the reaction section 4 of this application is a fixed bed, a moving bed, or a radial bed.

[0055] Furthermore, the catalyst in reaction section 4 is a water-stable catalyst, preferably a carbon-based catalyst.

[0056] Carbon-based catalysts can adsorb large amounts of impurities such as metals, colloids, and unsaponifiables in raw materials. After being discharged from the bottom of the reactor, carbon-based catalysts can be regenerated by high-temperature calcination, restoring their activity and being recycled multiple times, reducing the amount of catalyst used and the amount generated as hazardous waste. At the same time, the useful components in carbon-based catalysts can be recovered through incineration.

[0057] In one specific embodiment, a five-stage tandem hydrogenation device for producing bio-oil from waste animal and vegetable oils is constructed. The first to third stages form a reactor arranged vertically, and the fourth and fifth stages form another reactor arranged vertically, forming a dual-reactor system. The first reactor consists of three stages, and the second reactor consists of two stages, forming a five-stage tandem reaction system.

[0058] The product return rate is 5t / h. It is heated to 400℃ in the heating furnace 3. The raw material is preheated to 120℃ in the separator 2. The raw material is mixed with the product return at the first regulating valve 7 of the first stage, with a mixing temperature of about 260℃. The ratio of raw material to product return is about 1:1. It enters the first stage of the reactor at a pressure of 3.5MPa. The hydrogenation reaction takes place in the first stage, with the reaction temperature rising to 400℃. The total mass of oil and gas produced by the reaction is about 10t / h.

[0059] The raw material is mixed with the first reactant of the first stage at a rate of 10 t / h via the first regulating valve 7 of the second stage. The mixing temperature is about 260°C and the ratio of raw material to reactant is about 1:1. The mixture enters the second stage of the reactor and undergoes a hydrogenation reaction. The reaction temperature rises to 400°C, and the total mass of oil produced is 20 t / h.

[0060] The raw material is mixed with the reactants of the second stage at a rate of 20 t / h under the control of the first regulating valve 7 of the third stage. The mixing temperature is about 260°C and the ratio of raw material to reactants is about 1:1. The mixture enters the third stage of the reactor and undergoes a hydrogenation reaction. The reaction temperature rises to 400°C and the total mass of oil produced is 40 t / h.

[0061] The raw material is mixed with the reactants from the third stage at a rate of 40 t / h, controlled by the first regulating valve 7 in the fourth stage. The mixing temperature is about 260°C and the ratio of raw material to reactants is about 1:1. The mixture enters the fourth stage of the reactor, where a hydrogenation reaction is carried out. The reaction temperature rises to 400°C, and the total mass of oil produced is 80 t / h.

[0062] The raw materials are mixed with the reactants from the fourth stage at a rate of 80 t / h, controlled by the first regulating valve 7 in the fifth stage. The mixing temperature is about 260℃, and the ratio of raw materials to reactants is about 1:1. The mixture then enters the fifth stage of the reactor, where a hydrogenation reaction takes place. The reaction temperature rises to 400℃, and the total reaction mass is 160 t / h (including 5 tons of product return material). That is, 155 tons of total reaction raw materials are hydrogenated, and after being refined, separated, and having waste heat recovered by separator 2, 125.5 t / h of bio-oil is produced, with a total product yield of 80.96%.

[0063] This embodiment, after verification, uses 5 tons of recycled product as a heat source to complete the hydrogenation reaction of 155 tons of raw material through a five-stage scale-up process. The first stage reduces consumption by 20%, the second by 46.7%, the third by 77.14%, the fourth by 89.3%, and the fifth by 94.8%. From the perspective of energy consumption and investment in heating furnace 3, the five-stage series hydrogenation process requires only 5.2% of the total energy consumption for heating 155 tons of raw material to complete the hydrogenation reaction, achieving highly efficient hydrogenation of 155 tons of raw material. The scale-up factor of the five-stage hydrogenation reaction is 31 times.

[0064] In this embodiment, the catalyst deactivated after 6 months of use. During this period, the carbon-based catalyst did not break or become clogged in the reaction layer. Part of the deactivated catalyst was discharged through two catalyst unloading devices 12, and fresh catalyst was then added through the catalyst loading devices 11 of the two reactors, enabling online catalyst replacement. The discharged carbon-based catalyst underwent three regeneration cycles and was reused four times, reducing catalyst costs by 70% compared to other devices.

[0065] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A tandem hydrogenation reaction system with online catalyst replacement, characterized in that, The tandem hydrogenation reaction system includes: A heating furnace (3) is used to fill and heat the circulating oil; M-section reaction section (4), M≥2, the reaction sections (4) of each section are connected in series, the inlet of the first reaction section (4) is connected to the outlet of the heating furnace (3), and the preheated circulating oil is delivered from the (N-1)th reaction section (4) to the Nth reaction section (4); Separator (2), the separator (2) is provided with a feed port (1) for adding raw materials, the inlet of the separator (2) is connected to the outlet of the reaction section (4) of the Mth segment, and the outlet of the separator (2) is connected to the inlet of each reaction section (4); The reaction section (4) is provided with a catalyst loading device (11) above it and a catalyst unloading device (12) below it, so as to replace the catalyst in the reaction section (4).

2. The tandem hydrogenation reaction system according to claim 1, characterized in that, The tandem hydrogenation reaction system also includes: Multiple first flow lines (6) are provided, with their two ends connected to the inlet of each reaction section (4) and the outlet of the separator (2), respectively.

3. The tandem hydrogenation reaction system according to claim 2, characterized in that, The catalyst-based tandem hydrogenation reaction system also includes: Multiple first regulating valves (7) are provided on the first flow line (6) to regulate the raw materials entering each of the reaction sections (4).

4. The tandem hydrogenation reaction system according to claim 2, wherein the plurality of reaction sections (4) constitute a reactor, characterized in that, Multiple reaction segments (4) are stacked, and the height of the Nth reaction segment (4) is lower than that of the (N-1)th reaction segment (4); and / or The inlet of the reaction section (4) of the N-1th segment and the outlet of the reaction section (4) of the Nth segment are connected by a second flow line (8) so that the reaction section (4) of the N-1th segment and the reaction section (4) of the Nth segment are arranged side by side.

5. The tandem hydrogenation reaction system according to claim 4, characterized in that, When multiple reaction sections (4) are stacked, the catalyst loading device (11) is located at the inlet of the uppermost reaction section (4), and the catalyst unloading device (12) is located at the outlet of the lowermost reaction section (4), so that the catalyst of multiple reaction sections (4) can be replaced online.

6. The tandem hydrogenation reaction system according to claim 2, characterized in that, The separator (2) is connected to the heating furnace (3) through a third flow line (9), and a second regulating valve (10) is provided on the third flow line (9) to regulate the raw materials entering the heating furnace (3).

7. The tandem hydrogenation reaction system according to claim 1, characterized in that, The reaction temperature in the reaction section (4) is 260° to 400°.

8. The tandem hydrogenation reaction system according to claim 1, characterized in that, The ratio of the raw material to the circulating oil in each reaction section (4) is 0.3 to 3.

9. The tandem hydrogenation reaction system according to claim 1, characterized in that, The reaction section (4) is one of the following: boiling bed, fixed bed, moving bed, radial bed, expansion bed, and suspension bed.

10. The tandem hydrogenation reaction system according to claim 1, characterized in that, The catalyst in the reaction section (4) is a catalyst with good water stability.

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