Fluidized bed methanol-to-propylene process system
By optimizing the methanol-to-propylene process system through a fluidized bed, the process flow is improved. Steam is generated by utilizing the heat of reaction and an external heat exchanger, which solves the problems of low product yield, high energy consumption, complex operation, high investment cost, and large footprint in existing technologies, and achieves efficient and low-cost propylene production.
Patent Information
- Application Number
- CN202520423709.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-11
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-03-11
AI Technical Summary
Existing methanol-to-propylene processes suffer from problems such as low product yield, high energy consumption, complex operation, high investment costs, and large land area requirements.
A fluidized bed methanol-to-propylene process system, including a reactor and a regenerator, is adopted. By rationally arranging the connection of methanol feedstock pipes, vaporizers, superheaters and quench towers, the heat of reaction is used to preheat, vaporize and superheat the methanol feedstock. Combined with the steam generated by an external heat exchanger, the catalyst regeneration process is optimized, and the heat utilization rate and catalyst activity recovery are improved.
It improved product yield, reduced energy consumption and investment costs, simplified operating procedures, reduced floor space, and achieved efficient utilization of heat and effective regeneration of catalysts.
Smart Images
Figure CN223945625U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the production propylene technical field, concretely relates to a fluidized bed methanol preparation propylene process system. BACKGROUND
[0002] Propylene is an extremely important organic chemical raw material, and is widely used in multiple fields, and can be used for producing various important organic chemical raw materials, and its use is producing polypropylene, acrylonitrile, propylene oxide, acrylic acid and its esters, isopropyl alcohol, propionaldehyde, butenol, ethylene propylene rubber, methyl tertiary butyl ether and the like; in recent years, propylene replaces paper, steel, wood and other non-plastic materials and expensive synthetic resins.
[0003] Methanol preparation propylene technology refers to a chemical process technology for producing propylene under the action of a catalyst by taking coal-based or natural gas-based synthetic methanol as raw material, and the methanol preparation propylene technology has good application prospect and far-reaching strategic significance in view of the energy structure of rich coal, poor oil and little gas in China.
[0004] Lurgi of Germany is a company that successfully industrializes the methanol preparation propylene technology in the world, and the reaction equipment of the technology mainly comprises a dimethyl ether fixed bed reactor and a methanol preparation propylene fixed bed reactor, and the advantage of the technology is high propylene selectivity, which can reach about 70%; the fixed bed reactor has the advantages of mature technology, simple operation and easy amplification; the limitation is relatively high investment cost, large energy consumption, production needs to switch regenerated catalyst, and poor regeneration performance. CONTENT OF THE UTILITY MODEL
[0005] The utility model aims at providing a fluidized bed methanol preparation propylene process system, so as to solve the problems of low product yield, high energy consumption, complex operation, high investment cost and large occupied area in the production of propylene from methanol.
[0006] In order to realize the above-mentioned purpose, the utility model adopts the following technical scheme:
[0007] The application discloses a fluidized bed methanol-to-propylene process system, which comprises a reactor and a regenerator, the reactor comprises a reaction first section and a reaction second section which are communicated with each other, the regenerator comprises a regeneration first section and a regeneration second section which are communicated with each other, a methanol raw material pipe, a methanol vaporizer, a methanol superheater and a raw material inlet of the reaction first section are sequentially communicated, and methanol raw material is sequentially reacted in the reaction first section and the reaction second section to form product gas; a product gas outlet of the reaction second section, the methanol superheater, the methanol vaporizer, a quenching tower and a product gas output pipe are sequentially communicated; a catalyst outlet of the reaction first section is communicated with a catalyst inlet of the regeneration second section, a catalyst outlet of the regeneration second section is communicated with a catalyst inlet of the reaction first section, a catalyst outlet of the reaction second section is communicated with a catalyst inlet of the regeneration first section, and a catalyst outlet of the regeneration first section is communicated with a catalyst inlet of the reaction second section; an internal heat exchanger coil of the reaction first section is arranged in the reaction first section, an internal heat exchanger inlet and an internal heat exchanger outlet of the internal heat exchanger coil of the reaction first section are both communicated with the methanol raw material pipe, and a first valve is arranged on the methanol raw material pipe and located between the internal heat exchanger inlet and the internal heat exchanger outlet; the reaction first section is communicated with a reaction first external heat exchanger which is located outside the reaction first section, the reaction second section is communicated with a reaction second external heat exchanger which is located outside the reaction second section, the regeneration first section is communicated with a regeneration first external heat exchanger which is located outside the regeneration first section, and the regeneration second section is communicated with a regeneration second external heat exchanger which is located outside the regeneration second section.
[0008] As a preferred technical scheme in the application, the reaction first section and the reaction second section are integrally formed, and the reaction first section is located at the lower end of the reaction second section; the upper end of the reaction first section is communicated with the reaction second section through a reaction distributor, and the reaction distributor is located inside the reaction second section.
[0009] As a preferred technical scheme in the application, the internal heat exchanger coil of the reaction first section is arranged at the top of the reaction first section close to the reaction distributor.
[0010] As a preferred technical scheme in the application, the reaction first section and the reaction second section are two independent containers, and the reaction first section and the reaction second section are communicated through a reflection pipeline.
[0011] As a preferred technical scheme in the application, the top of the inner side of the reaction second section is provided with a reaction coarse cyclone, the product gas outlet of the reaction second section is communicated with the outlet of the reaction coarse cyclone, and the product gas outlet of the reaction second section is communicated with the methanol superheater after passing through a reaction fine cyclone.
[0012] As a preferred technical scheme in the application, the regeneration first section and the regeneration second section are integrally formed, and the regeneration first section is located at the lower end of the regeneration second section; the upper end of the regeneration first section is communicated with the regeneration second section through a regeneration distributor, and the regeneration distributor is located inside the regeneration second section.
[0013] As one preferred technical scheme in the utility model, the regenerating first section and the regenerating second section are two independent containers, and the regenerating first section and the regenerating second section are communicated through a regenerating pipeline.
[0014] As one preferred technical scheme in the utility model, the top of the inside of the regenerating second section is provided with a regenerating coarse cyclone, the outlet of the regenerating coarse cyclone is communicated with the flue gas outlet at the top of the regenerating second section, and the flue gas outlet of the regenerating second section is communicated with the flue gas discharge pipe through a regenerating fine cyclone.
[0015] Beneficial effects:
[0016] 1. The methanol raw material pipe, the methanol vaporizer, the methanol superheater and the raw material inlet of the reaction first section are sequentially communicated, the methanol raw material is sequentially reacted after passing through the reaction first section and the reaction second section to form product gas, the product gas outlet of the reaction second section, the methanol superheater, the methanol vaporizer, the quenching tower and the product gas output pipe are sequentially communicated, the process system for producing propylene is reasonable in layout, simple in structure, small in land occupation and low in investment cost; the liquid methanol raw material is pumped into the heat taking coil in the reaction first section from the liquid raw material tank area, the methanol after heat taking enters the methanol vaporizer, the vaporized methanol raw material enters the reactor after being superheated by the methanol superheater, the vaporizer and the superheater are arranged, the temperature of the methanol raw material is effectively improved, the operation is easy and the control is good, and the yield of the target product is improved; on the other hand, the product gas is superheated by the methanol superheater using waste heat, the product gas after being superheated by the methanol enters the methanol vaporizer to vaporize the methanol raw material, and then is sent to the quenching tower to wash the catalyst and reduce the temperature of the product gas, the heat source of the methanol raw material comes from the reactor, the methanol raw material is preheated, vaporized and superheated by the reaction heat, the heat utilization rate is high, energy consumption is reduced, and the production cost is low.
[0017] 2. The catalyst in the reaction first section can enter the regeneration second section for coking regeneration after losing activity, and the regenerated catalyst with restored activity enters the reaction first section to continue the dehydration reaction; the catalyst in the reaction second section can enter the regeneration first section for coking regeneration after losing activity, and the regenerated catalyst with restored activity enters the reaction second section to continue the main reaction of methanol to propylene.
[0018] 3. The reactor and the regenerator are both provided with an external heat taking device, the external heat taking device can produce steam required in the device, and at the same time, the temperature of the reactor and the regenerator is reduced, the external heat taking device adopts an external heat taking and back mixing form, is convenient to operate, easy to control, safe and reliable, high in heat utilization, steam production, low in energy consumption and low in operation cost. BRIEF DESCRIPTION OF DRAWINGS
[0019] Figure 1 It is a system structure diagram of the utility model.
[0020] In the diagram: 1-Reactor; 2-Regenerator; 3-Methanol vaporizer; 4-Methanol superheater; 5-Reaction fine vortex; 6-Quick cooler; 7-External heat exchanger for reaction one; 8-External heat exchanger for reaction two; 9-Internal heat exchanger coil for reaction one; 10-Reaction coarse vortex; 11-Reaction distributor; 12-External heat exchanger for regeneration one; 13-External heat exchanger for regeneration two; 14-Regeneration coarse vortex; 15-Regeneration distributor; 16-Regeneration fine vortex; 101-Methanol feedstock pipe; 102-Product gas output pipe; 103-Flue gas emission pipe. Detailed Implementation
[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the present utility model will be briefly introduced below in conjunction with the accompanying drawings and descriptions of the embodiments or the prior art. Obviously, the following description of the structure of the accompanying drawings is 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. It should be noted that the description of these embodiments is used to help understand this utility model, but does not constitute a limitation on this utility model.
[0022] Example:
[0023] like Figure 1 As shown, this embodiment provides a fluidized bed methanol-to-propylene process system, including a reactor 1 and a regenerator 2. The reactor 1 includes a first reaction stage and a second reaction stage connected to each other, and the regenerator 2 includes a first regeneration stage and a second regeneration stage connected to each other. A methanol feedstock pipe 101, a methanol vaporizer 3, a methanol superheater 4, and the feedstock inlet of the first reaction stage are connected in sequence. The methanol feedstock reacts sequentially through the first and second reaction stages to form product gas. Simultaneously, an internal heat exchanger coil 9 is installed inside the first reaction stage. The inlet and outlet of the internal heat exchanger coil 9 are both connected to the methanol feedstock pipe 101, and a first valve is installed on the methanol feedstock pipe 101 located at the inlet and outlet of the internal heat exchanger. (The last sentence appears to be incomplete and possibly refers to a start-up process.) First, the first valve is closed. After the methanol feedstock enters the reaction section and releases heat, the first valve is closed again. At this time, the methanol feedstock is first sent to the heat exchanger coil 9 in the reaction section. After being heated to 60-80℃, it enters the methanol vaporizer 3 to vaporize the methanol. The temperature of the vaporized methanol is 100-120℃. Then, it is superheated to 150-200℃ by the methanol superheater 4 before entering the reactor 1 for reaction. The appropriate feed temperature effectively improves the conversion rate and the yield of the target product. The reaction heat is used to preheat, vaporize, and superheat the methanol feedstock, utilizing heat balance to save energy, reduce consumption, and lower production costs. In addition, during the start-up process, the methanol vaporizer 3 can be set to low-pressure steam vaporization, and an independent start-up heater can be set up to superheat the methanol to achieve the start-up purpose.
[0024] The product gas outlet of the reaction second section, the methanol superheater 4, the methanol vaporizer 3, the quench tower 6 and the product gas output pipe 102 are sequentially communicated, the product gas is heated by the waste heat of the methanol superheater 4, the product gas is heated to the methanol, the methanol is vaporized in the methanol vaporizer 3, and then is sent to the quench tower 6 to wash the catalyst and reduce the product gas temperature, the heat source of the methanol raw material is from the reactor 1, the methanol raw material is preheated, vaporized and overheated by the reaction heat 1, the heat utilization rate is high, the energy consumption is reduced, and the production cost is low.
[0025] The catalyst outlet of the reaction first section is communicated with the catalyst inlet of the regeneration second section, the catalyst outlet of the regeneration second section is communicated with the catalyst inlet of the reaction first section, the methanol raw material is dehydrated in the catalyst of the reaction first section, the dimethyl ether is generated after the methanol is dehydrated, enters the reaction second section, reacts with the catalyst of the reaction second section to generate propylene as product gas, wherein the catalyst of the reaction first section loses activity after reacting with the methanol raw material, the catalyst carrying coke in the reaction first section enters the regeneration second section for coke burning and regeneration, and the catalyst with recovered activity enters the reaction first section to continue the dehydration reaction.
[0026] The catalyst outlet of the reaction second section is communicated with the catalyst inlet of the regeneration first section, the catalyst outlet of the regeneration first section is communicated with the catalyst inlet of the reaction second section, the catalyst in the reaction second section loses activity after reacting with the dimethyl ether, the catalyst carrying coke in the reaction second section enters the regeneration first section for coke burning and regeneration, and the catalyst with recovered activity enters the reaction second section to continue the main reaction of methanol to propylene.
[0027] On the basis, the reaction first section is communicated with the reaction first external heat exchanger 7 located outside, the reaction second section is communicated with the reaction second external heat exchanger 8 located outside, the reaction first external heat exchanger 7 and the reaction second external heat exchanger 8 take out the heat emitted in the inside, steam is generated in the inside, is used for other purposes, the energy consumption is reduced, the production cost is reduced, the heat balance in the reactor 1 is ensured, and the optimal conversion rate and product yield are ensured.
[0028] The regeneration first section is communicated with the regeneration first external heat exchanger 12 located outside, the regeneration second section is communicated with the regeneration second external heat exchanger 13 located outside, the regeneration first external heat exchanger 12 and the reaction second external heat exchanger 8 take out the heat emitted in the inside, steam is generated in the inside, is used for other purposes, the regeneration temperature in the regenerator 2 is ensured, the energy consumption is reduced, and the production cost is reduced.
[0029] As a preferred embodiment in the present embodiment, it needs to be further explained that the structure of the reaction heat 1 can have two kinds, one is that the reaction first stage and the reaction second stage are integrally formed, and the reaction first stage is located at the lower end of the reaction second stage, the upper end of the reaction first stage is communicated with the reaction second stage through the reaction distributor 11, and the reaction distributor 11 is located inside the reaction second stage. In this case, it is preferred that the heat exchanger coil 9 in the reaction first stage is arranged at the top of the reaction first stage close to the reaction distributor 11, and the heat exchanger coil 9 in the reaction first stage can take away the heat at the top of the reaction first stage, reduce the inlet temperature of the reaction second stage, improve the selectivity of methanol to propylene, and effectively improve the yield of propylene product. The other is that the reaction first stage and the reaction second stage are two independent containers, and the reaction first stage and the reaction second stage are communicated through the reflection pipeline. Two different options are provided for the structure of the reaction heat 1, which can be set according to the actual situation, and the applicability can be improved.
[0030] As a preferred embodiment in the present embodiment, it needs to be further explained that the top of the inside of the reaction second stage is provided with the reaction coarse cyclone 10, the product gas outlet of the reaction second stage is communicated with the outlet of the reaction coarse cyclone 10, and the product gas outlet of the reaction second stage is communicated with the methanol superheater 4 after passing through the reaction fine cyclone 5. The product gas of the reaction of the reaction second stage enters the catalyst carried by the reaction fine cyclone after passing through the reaction coarse cyclone cyclone catalyst, and the effect of the cyclone catalyst is obvious.
[0031] As a preferred embodiment in the present embodiment, it needs to be further explained that the structure of the regenerator 2 can have two kinds, one is that the regeneration first stage and the regeneration second stage are integrally formed, and the regeneration first stage is located at the lower end of the regeneration second stage, the upper end of the regeneration first stage is communicated with the regeneration second stage through the regeneration distributor 15, and the regeneration distributor 15 is located inside the regeneration second stage. The other is that the regeneration first stage and the regeneration second stage are two independent containers, and the regeneration first stage and the regeneration second stage are communicated through the regeneration pipeline. Two different options are provided for the structure of the regenerator 2, which can be set according to the actual situation, and the applicability can be improved.
[0032] As a preferred embodiment in the embodiment, it needs to be further explained that the top of the second regeneration section is provided with a coarse regeneration cyclone 14, the outlet of the coarse regeneration cyclone 14 is communicated with the flue gas outlet of the top of the second regeneration section, the flue gas outlet of the second regeneration section is communicated with the flue gas discharge pipe 103 through a fine regeneration cyclone 16, the regenerator 2 uses compressed air to regenerate the catalyst carrying the coke after the coking reaction, the first regeneration section uses complete regeneration, ensures that the compressed air is excessive in the flue gas, the flue gas after regeneration of the first regeneration section enters the second regeneration section through the regeneration distributor 15 for regeneration, the flue gas after regeneration enters the fine regeneration cyclone 16 again to carry the catalyst, the effect of the cyclone catalyst is obvious, the flue gas after cyclone enters the downstream waste heat recovery system, can produce steam, reduces the production cost, and the second regeneration section can use incomplete regeneration or complete regeneration according to the performance of the catalyst.
[0033] Finally, it should be noted that: the above only for the preferred embodiments of the present application, and not for limiting the scope of the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application, should be included in the scope of protection of the present application.
Claims
1. A fluidized bed methanol-to-propylene process system, characterized in that, It includes a reactor (1) and a regenerator (2). The reactor (1) includes a first reaction stage and a second reaction stage that are connected to each other. The regenerator (2) includes a first regeneration stage and a second regeneration stage that are connected to each other. The methanol feed pipe (101), the methanol vaporizer (3), the methanol superheater (4) and the feed inlet of the first reaction stage are connected in sequence. After the methanol feed is reacted in the first reaction stage and the second reaction stage, product gas is formed. The product gas outlet of the second reaction stage, the methanol superheater (4), the methanol vaporizer (3), the quench tower (6) and the product gas output pipe (102) are connected in sequence. The catalyst outlet of the first reaction stage is connected to the catalyst inlet of the second regeneration stage, the catalyst outlet of the second regeneration stage is connected to the catalyst inlet of the first reaction stage, the catalyst outlet of the second reaction stage is connected to the catalyst inlet of the first regeneration stage, and the catalyst outlet of the first regeneration stage is connected to the catalyst inlet of the second reaction stage. The reaction section is equipped with an internal heat exchanger coil (9). The internal heat exchanger inlet and outlet of the internal heat exchanger coil (9) are both connected to the methanol feed pipe (101). The methanol feed pipe (101) is equipped with a first valve located at the internal heat exchanger inlet and outlet. The reaction section is connected to an external heat exchanger (7) located outside it. The reaction section is connected to an external heat exchanger (8) located outside it. The regeneration section is connected to an external regeneration heat exchanger (12) located outside it. The regeneration section is connected to an external regeneration heat exchanger (13) located outside it.
2. The fluidized bed methanol-to-propylene process system according to claim 1, characterized in that, The first reaction section and the second reaction section are integrally formed, and the first reaction section is located at the lower end of the second reaction section. The upper end of the first reaction section is connected to the second reaction section through the reaction distributor (11), and the reaction distributor (11) is located inside the second reaction section.
3. The fluidized bed methanol-to-propylene process system according to claim 2, characterized in that, The heat exchanger coil (9) in the reaction section is located at the top of the reaction section near the reaction distributor (11).
4. The fluidized bed methanol-to-propylene process system according to claim 1, characterized in that, The first and second reaction sections are two independent containers, connected by a reflective pipe.
5. A fluidized bed methanol-to-propylene process system according to any one of claims 1-4, characterized in that, The top of the inner side of the second reaction section is provided with a coarse reaction vortex (10). The product gas outlet of the second reaction section is connected to the outlet of the coarse reaction vortex (10), and the product gas outlet of the second reaction section is connected to the methanol superheater (4) after passing through the fine reaction vortex (5).
6. The fluidized bed methanol-to-propylene process system according to claim 1, characterized in that, The first and second regeneration sections are integrally formed, with the first regeneration section located at the lower end of the second regeneration section. The upper end of the first regeneration section is connected to the second regeneration section through a regeneration distributor (15), which is located inside the second regeneration section.
7. The fluidized bed methanol-to-propylene process system according to claim 1, characterized in that, The first and second regeneration stages are two independent containers, connected by a regeneration pipeline.
8. A fluidized bed methanol-to-propylene process system according to claim 1, 6, or 7, characterized in that, The top of the inner side of the second regeneration stage is provided with a coarse regeneration vortex (14), the outlet of the coarse regeneration vortex (14) is connected to the flue gas outlet at the top of the second regeneration stage, and the flue gas outlet of the second regeneration stage is connected to the flue gas emission pipe (103) through a fine regeneration vortex (16).