JP5312355B2 - Reactor and reaction product manufacturing method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reactor in which a reaction product, that is obtained by a catalytic reaction, is condensed continuously, and the condensed reaction product is withdrawn to the outside without exerting a bad influence on the reaction temperature in the reactor, and in which a synthetic reaction is advanced to obtain higher yield. <P>SOLUTION: A gas introduction part 2 is arranged in a drum part 1b of the reactor 1 and a gas discharge part 7 is arranged in a central axis part of the reactor 1. A delivery part 5 comprises a cooling part 5a, a part of which comprises a triple pipe 50, and a withdrawal part 5b which is integrated with the cooling part and used for withdrawing a part of the reaction product. The triple pipe 50 comprises: an outer pipe 51 in which a cooling medium is introduced and circulated; an inner pipe 52 which is arranged in the outer pipe 51 and from the tip 52c of which a part of the reaction product is withdrawn; and an intermediate pipe 53 which is arranged on the outer periphery of the inner pipe 52 and on the inside of the outer pipe 51 and in which the cooling medium is circulated and discharged. The tip 52c of the inner pipe 52 is positioned in the reactor 1 in the upper part or almost in the center part thereof. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a reactor and a reaction product production method using the same, and is particularly useful for application to a methanol reactor and a methanol synthesis method using biomass as a raw material as a renewable energy.

  In various synthesis reaction processes such as a methanol synthesis process using biomass as a raw material, a DME synthesis process, or an FT (Fischer-Tropsch) synthesis process, an endothermic reaction or an exothermic reaction by a catalyst is used. At this time, in order to appropriately manage the reaction efficiency or the yield of the reaction product, it is necessary to manage the temperature of the reactor and the reaction tank, appropriately treat the reaction heat, and control the temperature of the catalyst. Particularly, in the exothermic reaction, since the heat removal method during the reaction greatly affects the reaction efficiency and the energy efficiency of the process, various ideas and proposals have been made for the configuration of the reactor.

Taking the case of an exothermic reaction as an example of a specific reactor type in the gas phase reaction, the following are used industrially (see, for example, Patent Document 1).
(I) Adiabatic quench reactor: A vertical cylindrical pressure vessel is filled with catalysts in multiple stages, and a raw material gas is supplied from above. Since the temperature rises due to heat generated as the reaction proceeds in the catalyst layer, the temperature of the catalyst layer is controlled by introducing a low-temperature source gas (quenching gas) between the catalyst layers.
(Ii) Tubular reactor: The catalyst is filled in the tube of a vertical heat exchanger, and boiler water is placed on the shell side to recover the reaction heat as water vapor.
(Iii) Tubular double-pipe reactor: A double pipe is used for the vertical heat exchanger, the catalyst is filled in the circumference between the inner pipe and the outer pipe, and the synthesis gas passes through the inner pipe And recovering the reaction heat as water vapor by putting boiler water outside the outer tube (shell side).
(Iv) Radial flow heat exchange reactor: A reaction gas is used as a radial flow, and a large number of heat transfer tubes are provided in the axial direction in the catalyst layer to recover the reaction heat as high-pressure and high-temperature steam.

For example, the methanol synthesis reaction is known to have the following reaction formula, and these are exothermic reactions.
CO + 2H ₂ → CH ₃ OH ..Formula 1
CO ₂ + 3H ₂ → CH ₃ OH + H ₂ O
CO + H ₂ O → H ₂ + CO ₂ .. Formula 3
In general, in the methanol synthesis reaction, the reaction of the above formula 1 is dominant, the reaction heat of the formula 1 is 90.8 kJmol ⁻¹ in the standard state, and the reaction has a large calorific value. Here, since the equilibrium conversion rate decreases as the temperature increases, it is necessary to appropriately remove the heat of reaction and sufficiently consider the temperature control of the catalyst when designing the reactor. In addition, various methods are considered because the heat removal method is related to the energy efficiency of the process.

The methanol synthesis reaction has a low one-pass conversion rate due to thermodynamic limitations, and therefore a reaction under a high pressure (8 to 12 MPa) that is advantageous in terms of chemical equilibrium is common, and is a process that consumes a large amount of energy. Yes. In addition, since methanol is synthesized by circulating unreacted raw material gas, the equipment is increased in size and complexity, and the equipment cost is high. Therefore, from the viewpoints of energy efficiency and economy, methanol is being produced only with a very large-scale facility of several thousand tons / day. On the other hand, methanol is mainly produced using natural gas or coal as raw material. However, with the background of global warming problems caused by depletion of fossil resources and CO ₂ emissions, biomass that is renewable energy is used as a raw material. Development of methanol production technology is underway. However, in general, biomass is a small-scale distributed resource, and conventional high-pressure / gas recycling methanol production technology is not preferable from the viewpoint of energy efficiency and economy, so various studies have been made for practical application. Yes.

  Specifically, as shown in FIG. 10, a method of synthesizing methanol by reacting a raw material gas mainly composed of hydrogen and carbon monoxide or carbon dioxide in the presence of a catalyst, There has been proposed a method in which a cooling surface below the dew point of the vapor pressure of methanol is present, methanol is liquefied and dropped on the cooling surface and extracted out of the reaction system, and methanol synthesis is performed at a conversion rate exceeding the equilibrium conversion rate. (For example, refer to Patent Document 2). The cooling body (cooling pipe) 104 is disposed inside the porous cylinder, and is formed in a spiral shape so as to increase the cooling area. If necessary, fins may be formed on the outer peripheral surface of the cooling pipe in order to increase the cooling area. In this embodiment, water is circulated inside the cooling body (cooling pipe) 104 as a cooling medium. Cooling water (normal temperature) is introduced from the cooling water inlet 110 at the top of the reaction vessel 101, and heat is exchanged between methanol generated in the catalyst packed bed 103 and the inner wall surface of the cooling body (cooling pipe) 104, and the temperature rises from 60 ° C. to It becomes 80 ° C. warm water and is discharged from the cooling water outlet 111. By this heat exchange, the produced methanol is liquefied and dropped to be extracted out of the reaction vessel 101.

  Furthermore, in such a reactor, since it is difficult to construct an ultra-large reactor, an air-water drum type ultra-large methanol reactor as shown in FIG. 11 has been proposed (see, for example, Patent Document 1). . Specifically, drums 202 and 204 for steam generation are provided in the upper part of the rigid reactor 201 and the lower part in the reactor 201, and a cooling pipe (heat transfer pipe group 205) is formed using a hemispherical tube plate. It has a structure for mounting and filling the catalyst in the reactor. Here, 203 is a downcomer pipe, 206 is an extension pipe, 207 is a catalyst tray, 208 to 212 are flow paths, and 213 to 215 are manways.

Japanese Patent No. 2964589 JP 2005-298413 A

However, the synthesis methods as described above sometimes have the following problems and problems.
(I) In the conventional technique, the heat generated by the exothermic reaction is taken out of the system, but the cooling temperature is equal to or higher than the dew point of the reaction product (for example, methanol) generated in any method. Therefore, there has been a problem that a synthesis reaction at a conversion rate exceeding the equilibrium conversion rate is impossible, and when the conversion rate approaches the equilibrium conversion rate, the reaction rate decreases and the efficiency of the reactor decreases.
(Ii) Also, the reaction proceeds sufficiently near the catalyst layer inlet because the concentration in the raw material gas is high and the reaction rate is high, but near the catalyst layer outlet, the concentration of the raw material gas is low and the reaction rate is not sufficient. There was a problem that the reaction did not proceed sufficiently.
(Iii) Generally, the cooling pipes are fixed at the upper and lower parts of the reactor. However, it is difficult to scale up the reactor to a practical machine scale because it causes damage to the cooling pipe due to the load caused by thermal stress.
(Iv) In such a configuration, the temperature of the lower part of the reactor may be lower than that of the upper part of the reactor, resulting in uneven temperature in the vertical direction, resulting in uneven temperature in the vertical direction of the cooling pipe or in the flow direction of the reaction gas. . For this reason, it is difficult to obtain the optimum sensitivity for the reaction in the entire catalyst layer, and in the case where a subtle change in the reaction temperature affects the reaction rate, such as an alcohol synthesis reaction, the condensation extraction of methanol is performed. In some cases, the methanol yield does not increase despite the fact that The same phenomenon occurs when the cooling tube is inserted from the top to the bottom of the reactor or when it is pushed upward from the bottom of the reactor. Accordingly, it is difficult to ensure a certain reaction rate and maintain an optimal reaction temperature, and there is a problem that a yield of a desired reaction product cannot be obtained.
(V) In addition, when a condensing part or a condensate extraction part is provided between the reaction tubes and the condensed gas returns to the catalyst layer again, a predetermined amount of condensate is stored. However, since the stored condensate is discharged out of the system at a constant rate or at regular intervals, the condensate cannot be secured continuously. In addition, in order to store condensate such as methanol, it is necessary to use not only the storage tank but also the entire reactor as a corrosion-resistant material, and the structure of the reactor, which is a pressure vessel, becomes complicated, which increases the manufacturing cost. There was a problem. Furthermore, it is necessary to reheat the gas introduced into the catalyst layer, resulting in a decrease in energy efficiency and an increase in the utility amount of the cooling water.
(Vi) Generally, the catalyst filling portion is a single tube type. When designing with a fixed gas flow rate, it is necessary to increase the tube diameter of the reaction tube as the gas flow rate increases. In the case of a pressure vessel, if the reaction tube diameter is increased, the required wall thickness increases accordingly. This increases the manufacturing cost. For these reasons, there is a problem that it is difficult to scale up the reactor to a practical scale.
(Vii) Further, when the method as shown in FIG. 10 is put into practical use, when the raw material gas is introduced into the catalyst packed bed, if a gas drift occurs, the reaction rate is lowered, and the catalyst packed bed Therefore, the structure of a reactor that can ensure a uniform gas flow has been a problem. In addition, a configuration in which the contact efficiency between purified methanol and the cooling pipe in the catalyst packed bed is increased and the condensation effect inside the reactor is improved is also an important issue.
(Viii) In the case where the method as shown in FIG. 11 is put into practical use, since a plurality of reaction tubes having catalyst packed layers are connected in series, there is a problem that charging and unloading of the catalyst becomes complicated. there were.

  Therefore, an object of the present invention is to continuously condense the reaction product obtained by the synthesis reaction of the raw material gas inside the reactor without affecting the reaction temperature in the reactor and extract it to the outside. At the same time, it is to provide a reactor capable of promoting the synthesis reaction and obtaining a higher yield, and a reaction product production method using the reactor. In particular, in the process of producing methanol from a raw material gas made from biomass, etc., a high conversion rate exceeding the equilibrium conversion rate can be secured in one pass, and a continuous high methanol yield can be obtained without circulating the raw material gas. There is in being able to.

  As a result of intensive studies, the present inventors have found that the above object can be achieved by the following reactor and a reaction product production method using the same, and have completed the present invention.

The present invention has a raw material gas introduction part, a catalyst packed bed, a reaction product delivery part and a reaction gas discharge part, and a reactor in which a reaction product is produced by catalytic reaction,
The source gas introduction part is provided in the body part of the reactor, the reaction gas discharge part is provided in the central shaft part of the reactor, and the reaction product supply part is inserted from the upper end part of the reactor, A reaction product cooling unit that forms a triple tube in the unit, and a reaction product extraction unit from which a part of the reaction product is extracted from the upper part of the reactor. An outer tube through which the reaction product is introduced and circulated, an inner tube provided inside the outer tube from which a part of the reaction product is extracted from the tip, and an outer periphery of the inner tube provided inside the outer tube And an inner tube through which the cooling medium is circulated and discharged, and a tip portion of the inner tube is located at an approximate center from the upper part inside the reactor.

  In order to increase the reaction rate in a reactor such as methanol synthesis, it is important how to reduce the influence of reaction heat generated by the reaction of the raw material gas. Moreover, it is preferable to condense and extract the reaction product in the catalyst packed bed. On the other hand, the condensation of the reaction product and the installation of the cooling part are major issues in reducing the temperature drop and uneven temperature distribution inside the catalyst packed bed. In the present invention, a triple tube having a cooling function is partially formed, and a reaction product extraction part (hereinafter referred to as “extraction”) from which a part of the reaction product is extracted from either the upper part or the substantially central part inside the reactor. By using the “outlet”) and forming the flow conditions and temperature conditions of the gas containing the optimal raw material gas and reaction product (hereinafter referred to as “reaction gas”) and the exhaust gas, a high yield can be achieved by an efficient synthesis reaction. It became possible to get.

Specifically, in the process of producing a reaction product from a raw material gas, the following configuration ensures a high conversion rate exceeding the equilibrium conversion rate in one pass, and a high yield can be obtained without circulating the raw material gas. It has become possible to provide a reactor that can be used.
(A) A higher conversion can be ensured by extracting the reaction product generated on the upstream side of the catalyst packed bed in the catalyst packed bed. In other words, in the reversible reaction, the chemical equilibrium can be shifted in the direction of promoting the reaction by removing the reaction product from the system, so the reaction product synthesized on the upstream side of the catalyst packed bed is condensed and reacted. This is based on the knowledge that the reaction can be promoted by extracting to the outside of the vessel and a higher yield can be obtained.
(B) It is possible to condense and extract the reaction product efficiently by condensing the reaction product by the cooling part up to the upper part or the substantially central part inside the reactor and extracting the reaction product from the end part. . In other words, by limiting the cooling part to the upper part of the catalyst packed bed or from the upper part of the catalyst packed bed to the substantially central part, temperature unevenness of the catalyst packed bed is eliminated and loss due to transpiration of reaction products in the flow-down process is prevented. We have obtained knowledge that we can do it.
(C) By flowing the raw material gas introduced from the body of the reactor in the direction perpendicular to the axial direction of the reactor and installing the cooling unit in the axial direction of the reactor, the gas surely passes through the catalyst packed bed. Can be.
(D) Ensuring high reaction efficiency by maintaining the temperature of the raw material gas, which varies depending on the reaction heat, within the optimum reaction temperature range using the cold energy of the reaction product cooling section (hereinafter referred to as “cooling section”). Can do.
Further, by inserting the extraction portion from the upper end portion of the reactor, it is possible to supply and recover the cooling medium from one direction, simplify the structure of the reactor, and It is possible to prevent an increase in temperature difference. Furthermore, it is possible to reduce the load due to the thermal stress on the cooling unit itself.

The present invention is the above reactor, wherein the outer peripheral portion of the triple tube inserted in the reactor is gradually reduced in outer diameter or partially having the same diameter portion, and the inner tube And a flat surface perpendicular to the central axis of the inner tube.
The condensed reaction product (condensate) falls along the outer peripheral surface of the triple tube by its own weight and is extracted from the inside of the triple tube. At this time, for example, when the outer peripheral end of the outer tube or the outer peripheral end of the triple tube tip is far from the inner wall of the inner tube tip, the condensate may fall from the outer peripheral end. The same applies to the case where the outer peripheral portion of the triple tube tip is formed parallel to the central axis of the inner tube or formed at an acute angle with respect to the tip of the inner tube. According to the present invention, the outer peripheral portion of the triple tube is gradually reduced in outer diameter or partially reduced while having the same diameter portion, and has a flat surface perpendicular to the central axis of the inner tube at the tip of the inner tube. With this structure, the condensate can flow into and out of the inner tube without falling from the outer peripheral end. Specific examples of the shape of the outer peripheral portion of the triple tube include a substantially conical shape, a substantially conical shape having a straight pipe portion in part, or a substantially conical shape having a swelling in part.

The present invention is the above-described reactor, wherein the reaction product supply section has a cylindrical porous plate that partitions the periphery of the triple tube, and a plurality of concentric arrays are arranged in the catalyst packed bed. To do.
The cooling section formed by the outer periphery of the triple pipe is responsible for ensuring the efficiency of the catalytic reaction by cooling the raw material gas, as well as condensing the reaction product inside the reactor by condensation on the surface of the cooling section. At this time, if the cooling unit is in direct contact with the catalyst, the reaction efficiency is reduced due to the decrease in the catalyst temperature due to heat conduction, and the recovery amount of the condensate due to the adhesion of the condensate to the catalyst surface is reduced. The reaction efficiency may be reduced. In the present invention, a cooling space (cooling layer) can be formed and a condensate recovery channel can be secured by partitioning the periphery of the cooling section with a cylindrical porous plate. In addition, by efficiently cooling and condensing the reaction product with a plurality of triple pipes, it is possible to ensure high recovery efficiency as a condensate, and in addition, the reaction products are sequentially formed by a plurality of cooling layers from upstream of the catalyst packed bed. It is possible to secure a high conversion rate exceeding the equilibrium conversion rate by recovering. Here, the term “concentric” refers to a case where a plurality of extraction portions are arranged so as to have a plurality of circular cross sections, and in the case of forming a plurality of circles, they are concentric, and a plurality of squares are formed. In the case of forming, a concentric shape having a common center point is used, and the same applies to the case of forming a plurality of other shapes.

The present invention is the above-described reactor, characterized in that the gas introduction part and the catalyst filling layer are partitioned by a gas rectification layer, and the rectified source gas is introduced to the catalyst filling layer.
In the catalytic reaction, a uniform gas flow inside the catalyst packed bed is preferable. The present invention realizes this in the supply of the raw material gas from the outside of the catalyst packed bed, and a gas rectifying layer is provided between the gas introduction part and the catalyst packed bed and between the reaction gas discharge part and the catalyst packed bed. This eliminates variations in the reaction efficiency in the catalyst packed bed and ensures a high reaction efficiency with the minimum capacity catalyst packed bed.

The present invention is the above-described reactor, characterized in that the reaction gas discharge part and the catalyst filling layer are partitioned by a gas rectifying layer to improve the uniformity of gas flow inside the catalyst filling layer.
The uniform flow of gas inside the catalyst packed bed is hindered by the formation of a drift in the specific flow path. In the present invention, by forming a similar rectifying function not only on the introduction side of the catalyst packed bed but also on the discharge side, it is possible to ensure higher uniformity of gas flow inside the catalyst packed bed, and to minimize the capacity. It is possible to ensure a high conversion rate by the catalyst packed bed.

The present invention is the above-described reactor, characterized in that a shielding plate for restricting the flow of gas is provided in the catalyst packed bed to improve the contact efficiency between the gas and the cooling unit.
In the above description, the gas passing through the catalyst packed bed is rectified to form a uniform gas flow inside the catalyst packed bed. The present invention aims to improve the contact efficiency between the gas and the cooling unit by regulating the flow of gas inside the catalyst packed bed. By disposing a shielding plate at an interval or at a predetermined location, it becomes possible to secure a high amount of condensation of the reaction product inside the reactor. That is, a reactor capable of securing a high conversion rate exceeding the equilibrium conversion rate in one pass and obtaining a high yield can be configured.

Further, the present invention is a reaction product manufacturing method using any of the above reactors, wherein the raw material gas is introduced in a direction perpendicular to the axial direction of the reactor, and is generated by a synthesis reaction of the catalyst packed bed. Part of the reaction product is condensed on the outer periphery of the triple tube, and part of the condensed reaction product is withdrawn to the outside of the reactor, and the partial pressure of the reaction product is reduced to fill the catalyst in the subsequent stage. It is characterized by promoting the synthesis reaction in the layer.
The reactor has the basic functions (a) to (d), and the present invention makes use of these excellent functions to secure a high conversion rate exceeding the equilibrium conversion rate in one pass, A reaction product production method capable of obtaining a high yield without circulation can be constructed. In particular, the reaction product production method based on the knowledge that (a) a high conversion rate exceeding the equilibrium conversion rate can be secured by sequentially recovering the reaction product from the upstream of the catalyst packed bed by a plurality of cooling layers. Unprecedented high yields can be obtained.

The whole block diagram which illustrates the basic composition of the reactor concerning the present invention. The block diagram which shows the structural example of the triple tube which concerns on this invention. The block diagram which shows the structural example of the front-end | tip part of the triple tube which concerns on this invention. The block diagram which shows the other structural example of the reactor which concerns on this invention. The block diagram which shows the structural example of the reaction product manufacturing apparatus provided with the reactor which concerns on this invention. The state diagram which illustrates the temperature distribution of the perpendicular direction in a catalyst packed bed as a structural example and experimental result of the experimental apparatus which concerns on this invention. Explanatory drawing which illustrates the temperature distribution of the horizontal direction in the catalyst packed bed which concerns on this invention. Explanatory drawing which illustrates the trial calculation result of the CO conversion rate of the synthesis reactor which concerns on this invention. Explanatory drawing which illustrates the trial calculation result of the temperature distribution and CO conversion rate of the synthesis reactor according to the present invention having a plurality of catalyst packed layers and cooling layers. The whole block diagram which illustrates the outline of the synthesis | combining method of 1 methanol which concerns on a prior art. The whole block diagram which illustrates the outline of the synthesis | combining method of other methanol which concerns on a prior art.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. A reactor according to the present invention (hereinafter referred to as “the present apparatus”) includes a raw material gas introduction section (hereinafter referred to as “gas introduction section”), a catalyst packed bed, and a reaction product supply section (hereinafter also referred to as “delivery section”). And a reactive gas discharge section (hereinafter also referred to as “gas discharge section”). The raw material gas introduction part is provided in the body part of the reactor (hereinafter referred to as “body part”), and the reaction gas discharge part is provided in the central shaft part of the reactor. A reaction product delivery unit is inserted from the upper end of the reactor, and a reaction product cooling unit (hereinafter referred to as “cooling unit”) partially forming a triple tube, and a reaction product from the upper part of the reactor. And a reaction product extraction part (hereinafter referred to as “extraction part”) from which the part is extracted. The triple pipe is composed of an outer pipe through which a cooling medium is introduced and circulated, an inner pipe provided inside the outer pipe from which a part of the reaction product is extracted from the tip, and an outer circumference of the inner pipe. And an inner pipe that is provided inside and from which the cooling medium is circulated and discharged. The distal end portion of the inner tube is located at any one of the substantially central portion from the upper portion inside the reactor.

<First configuration example of the apparatus>
As one embodiment of this apparatus, a schematic overall configuration of a first configuration example is shown in FIG. The cross section from the front of this apparatus 1 is shown to FIG. 1 (A), and the cross section from the front of the delivery part 5 is shown to FIG. 1 (B). In order from the outer periphery of the apparatus 1, the gas introduction unit 2, the first gas rectifying layer 3, and the catalyst packed layer 4 are configured. In the catalyst packed layer 4, one or a plurality of delivery units 5 are arranged concentrically. (In the first configuration example, an example in which one delivery unit 5 is provided is shown). A central portion of the catalyst packed layer 4 is partitioned by the second gas rectifying layer 6 and a gas discharge portion 7 is provided. There is a gas introduction part 2 at the outermost peripheral part inside the apparatus 1, and the raw material gas introduced from the raw material gas inlet 2 a is perpendicular to the axial direction M of the apparatus 1 from the entire outer periphery through the gas introduction part 2. Flow in the direction. A first gas rectifying layer 3 is provided between the gas guiding portion 2 and the catalyst packed layer 4. The source gas uniformly dispersed in the first gas rectifying layer 3 is introduced into the catalyst packed layer 4 in a direction perpendicular to the axial direction M. The catalyst packed bed 4 is filled with a synthesis reaction catalyst (for example, a methanol synthesis catalyst). The raw material gas introduced into the catalyst packed bed 4 reacts to become a reaction gas containing a reaction product, and a part of the reaction product that comes into contact with the cooling part 5a on the outer surface of the delivery part 5 when passing through the delivery part 5 Condenses. The reaction gas separates the reaction product condensed in the delivery unit 5 and is discharged through the second gas rectifying layer 6 and the reaction gas discharge unit 7 as an exhaust gas. The reaction product condensed in the cooling unit 5 a flows down to the lower part of the delivery unit 5 along the outer surface of the cooling unit 5 a by its own weight, and is extracted from the lower end of the delivery unit 5.

  In the above description, the case where the gas flows from the gas introduction part 2 provided in the innermost outer peripheral part of the apparatus 1 to the reaction gas discharge part 7 in the central part has been explained. It is also possible to use a configuration that introduces and flows out to the outer periphery. In that case, the structure of the apparatus 1 and the function of each part are the same as described above. In particular, by having the first gas rectifying layer 3 and the second gas rectifying layer 6, it is possible to make them compatible.

  The arrangement and dimensions of the delivery part 5 and the catalyst packed bed 4 are determined from the reaction conditions (gas amount, gas concentration, pressure) and economical conditions (reactor tower diameter, height).

For example, in the case of a methanol production apparatus as described above, the introduced raw material gas is mainly composed of H ₂ and CO or CO ₂ , steam reforming of natural gas, gasification of coal or biomass, or sewage A gas (synthetic gas) obtained by steam reforming of biogas produced in methane fermentation in a treatment plant or the like can be targeted.

[Functions of components of this device]
The apparatus 1 is a metal pressure vessel that can withstand the use conditions (pressure) of the synthesis reaction, and is a vertical cylindrical vessel. Generally, a pressure vessel made of carbon steel or stainless steel (SUS) is used. it can. A baffle plate can be installed inside the source gas inlet 2a to have a function of dispersing the gas. Moreover, the installation location and the number of source gas inlets 2a are not particularly specified. Since the present apparatus 1 can obtain a high conversion rate exceeding the equilibrium conversion rate in one pass as described above, it can obtain a yield similar to the conventional one under a lower pressure than the conventional reaction conditions. The power required to compress the raw material gas can be reduced. In addition, since high yields can be obtained without circulating the source gas, it is possible to omit equipment such as a circulation pump that was conventionally required for off-gas circulation, simplifying equipment, reducing costs, and saving space. Can be achieved. Therefore, for example, it can be suitably used in a relatively small scale (several hundred kg / day to several tons / day production scale) methanol production plant using biomass or the like as a raw material.

  It is preferable that the gas introduction part 2 and the catalyst packed layer 4 are partitioned by the first gas rectifying layer 3 and the rectified source gas is guided to the catalyst packed layer 4. The first gas rectifying layer 3 is a porous plate made of a metal such as a sintered metal plate or a ceramic, and has many holes sufficiently smaller than the catalyst particles. However, it is preferable that the pores be fine enough to uniformly disperse the source gas in the gas guide section 2 and that the pressure loss of the first gas rectifying layer 3 is not excessive under the conditions (pressure and flow rate) of the synthesis reaction. The first gas rectifying layer 3 is coupled to the body portion 1b of the reactor 1 at the upper and lower ends thereof by annular end portions 1a and 1c, and the coupling portion has a sealing structure that prevents gas from flowing (for example, sealing with an O-ring), Or it was completely sealed by welding.

  In the case of the above methanol production apparatus, a copper-zinc solid methanol synthesis catalyst is often used as the catalyst filled in the catalyst packed bed 4. In many of these synthesis reactions, when the reaction proceeds in the catalyst packed bed 4, the catalyst temperature rises according to the gas traveling direction. However, when the reaction temperature rises to a predetermined temperature, it is subject to thermodynamic equilibrium constraints. In the present apparatus 1, the raw material gas is introduced into the delivery unit 5 after passing through the catalyst packed bed length that reaches chemical equilibrium or less. The catalyst packed bed length is determined from the reaction rate determined according to the reaction conditions (pressure, raw material gas concentration, catalyst SV value, catalyst performance, gas temperature), and is not particularly specified. The catalyst is filled and withdrawn from the catalyst filling port 4a and the catalyst outlet 4b, and is provided at the upper and lower pressure-resistant portions of the apparatus 1, respectively. As a result, the catalyst can be easily exchanged even in a reactor having a plurality of catalyst packed beds 4 and delivery parts 5.

  The temperature of the catalyst packed bed 4 is set so as to be within a temperature range in which each reaction proceeds efficiently, and may be maintained at 170 to 250 ° C. (preferably 190 to 250 ° C.) in the methanol synthesis reaction. preferable. If it is less than 170 ° C., it is unreacted, 190 ° C. is generally an upper limit value at which performance degradation due to carbon deposition occurs in a methanol synthesis catalyst, and 250 ° C. is a lower limit value at which a copper catalyst causes performance degradation due to sintering. . Although it is not limited to this value depending on the catalyst performance, when a general copper-zinc solid methanol synthesis catalyst is used, it is preferably maintained at 200 to 230 ° C. This is because a low temperature is preferable from the viewpoint of chemical equilibrium, while a high temperature is advantageous from the viewpoint of reaction rate. By maintaining the temperature at 200 to 230 ° C., the reaction rate in the catalyst packed bed 4 can be maximized. .

  The catalyst packed bed 4 is provided with a delivery portion 5. The delivery unit 5 has a portion inserted in the apparatus 1 having a triple-pipe structure, and a gas containing a reaction product (hereinafter referred to as “extraction gas”) is extracted from the upper part of the apparatus 1. It consists of the extraction part 5b, and is comprised integrally. As shown in FIG. 1B, the cooling unit 5 a includes an outer tube 51 that forms the outermost part, an inner tube 52 provided inside the outer tube 51, and an outer periphery of the inner tube 52. It is comprised by the triple tube 50 which consists of the middle tube | pipe 53 provided in this. By fixing one end of the triple tube 50 to the upper part of the apparatus 1, it is possible to reduce the load due to thermal stress. A flow passage 51b through which a cooling medium is introduced and circulated is formed between the outer tube 51 and the outer periphery 53a of the middle tube 53, and the inner tube 53 is cooled between the outer periphery 52a and the inner tube 52. A flow passage 53b through which the medium is introduced and circulated is formed. The flow passage 51b and the flow passage 53b are connected at the lower part of the triple pipe 50. Further, an extraction path 52b through which the extracted gas is extracted is formed inside the inner pipe 52. However, the cross-sectional shape of the triple tube 50 is not limited to being formed concentrically, and various shapes such as an ellipse, a square, a rectangle, and a rhombus are possible.

  As the cooling medium is introduced and circulated into the flow passage 51b, the outer tube 51 is cooled, and the reaction product produced in the catalyst packed bed 4 is condensed on the outer peripheral portion 51a of the outer tube 51. The condensed reaction product flows down along the surface of the outer peripheral portion 51a of the outer tube 51 by its own weight, and the tip of the inner tube 52 that forms the lower end portion of the triple tube 50 while maintaining the liquid state by the cold heat of the outer peripheral portion 51a. The portion 52c is introduced into the inner tube 52. The introduced reaction product ascends inside the inner tube 52 and is extracted as a part of the extracted gas from the extraction portion 5b to which the inner tube 52 is connected. The cooling medium is introduced from the upper part of the apparatus 1 into the flow path 51b, flows through the flow path 53b, and is discharged from the upper part of the apparatus 1. At this time, since the outer peripheral portion 52a of the inner pipe 52 can maintain a low temperature by the cold heat of the cooling medium flowing through the flow passage 53b, the extracted reaction product can maintain a liquid state and the flow passage. Since the temperature does not fall below 51b, there is no new condensation in the extracted gas, no growth of the liquid material is promoted, and no dripping inside the apparatus 1 occurs.

  Here, it is preferable that the distal end portion 52c of the inner tube 52 is positioned at any one of the substantially central portion from the upper portion inside the apparatus 1. When a cooling pipe is disposed from the upper layer portion to the lower layer portion of the catalyst packed bed 4 and brought into contact with the reaction gas, the temperature in the catalyst packed bed in which various elements such as natural convection in the catalyst packed bed are related to each other. It becomes easy to generate unevenness. Moreover, since the time for which the condensate of the reaction product stays in the reactor becomes long, the condensate tends to evaporate, and the yield of the reaction product in the extracted gas tends to decrease. As shown in FIG. 1 (A), the cooling unit 5a is limited to the middle and upper layers inside the apparatus 1, and the condensed reaction product is extracted from the tip 52c, thereby eliminating such influence and improving efficiency. It was possible to obtain a high yield by a good synthesis reaction. The temperature drop and temperature unevenness of the catalyst packed bed 4 due to the reaction product condensing and flowing down to the lower layer of the catalyst packed bed 4 along the cooling unit 5a are eliminated, and the reaction product is evaporated in the flow-down process or the storage process. It has been found that loss can be prevented. The specific technical effect of such a structure is shown in the verification results described later.

  2A to 2C exemplify the configuration of the delivery unit 5 as a whole. By using the outer pipe 51 and the middle pipe 53 of the triple pipe 50 as the cooling medium flow path, the cooling section 5a can supply and recover the cooling medium from one direction, and the structure of the cooling section 5a can be simplified. In addition, the temperature difference in the vertical direction of the catalyst packed bed 4 can be prevented from being enlarged. The cooling medium may flow in any direction from the flow passage 51b to the flow passage 53b or from the flow passage 53b to the flow passage 51b when a predetermined flow rate or more is circulated. When a small amount of cooling medium is used, the reaction gas is cooled in the initial low temperature condition in the outer pipe 51 by flowing from the flow path 51b to the flow path 53b, and is slightly heated in the middle pipe 53. By exchanging heat with the inner pipe 52 (externally extracted gas) under the above-mentioned conditions, there is no new condensation and no growth of the liquid material is promoted.

  For example, in the methanol production process, the outer surface of the outer tube of the cooling unit 5 a is kept at a temperature lower than the dew point of the generated methanol in the gas introduced into the supply unit 5. Therefore, the type of the cooling medium and the temperature and flow rate of the cooling medium are set so as to satisfy the optimum conditions according to the methanol concentration in the gas introduced into the supply unit 5 and the reaction pressure. Specifically, the average temperature of the reaction gas in the delivery unit 5 is preferably maintained at 170 to 250 ° C. (desirably 190 to 250 ° C.) which is an appropriate temperature range of the catalyst packed bed 4. Moreover, since the liquid methanol containing impurities may show corrosiveness, the cooling part 5a which the liquid methanol touches is preferably a corrosion-resistant material such as stainless steel.

  Here, as illustrated in FIGS. 3A and 3B, the structure of the tip of the cooling unit 5a is gradually reduced, or the outer diameter of the outer tube 51a is gradually reduced or partially reduced while having the same diameter. In addition, it is preferable that the tip 52c of the inner tube 52 has a flat surface 52d perpendicular to the central axis N of the inner tube 52. Specific examples include a substantially conical shape, a substantially conical shape having a straight pipe portion in part, or a substantially conical shape having swelling in part. The reaction product (condensate) condensed at the outer periphery 51a flows down by its own weight. At this time, as illustrated in FIG. 3C, when the outer peripheral end 51c at the tip of the outer tube 51 or the triple tube 50 is far from the extraction path 52b of the tip 52c of the inner tube 52, much of the condensate is present. It may fall from the outer peripheral end 51c. In addition, as illustrated in FIG. 3D, when the outer peripheral portion 51a is formed at an acute angle with respect to the distal end portion 52c of the inner tube 52, much of the condensate may fall from the distal end portion 52c. In this apparatus, as shown in FIG. 3A, the outer peripheral portion 51a of the triple tube 50 is gradually reduced while having the same outer diameter portion in part and the tip portion 52c has a central axis N. By having a structure having a vertical flat surface 52d, or a structure having a flat surface 52d perpendicular to the central axis N at the distal end portion 52c, as shown in FIG. Thus, the condensate can flow into the extraction passage 52b inside the inner pipe 52 without falling from the outer peripheral end 51c.

  3A and 3B, the inner diameter d1 of the extraction path 52b is preferably 2 to 5 mmφ. Condensate can be transported with a small amount of extracted gas without clogging with dust. The width d2 of the flat surface 52d is preferably 1 to 5 mm. If it is less than 1 mm, it is close to the structure illustrated in FIG. 3D, and if it exceeds 5 mm, it is close to the structure illustrated in FIG. It will cause a decline. Furthermore, as illustrated in FIG. 3E, the outer periphery in the vicinity of the inner tube 52 including the tip 52c is covered with a porous body 54 made of metal such as a metal nonwoven fabric or sintered metal or ceramics. The condensate can pass through the inside of the porous body 54 cooled by the cold heat from the outer tube 51 and flow into the extraction passage 52b. Further, as illustrated in FIG. 3 (F), a condensate receiving portion 55 is provided at the tip 52c, and the outer peripheral portion 51a in the vicinity thereof is provided with lateral hole portions 52e and 52e that are electrically connected to the extraction passage 52b. The condensate falling from the part 51a and received by the receiving part 55 can be allowed to flow into the extraction path 52b.

  It is preferable that the gas exhaust unit 7 and the catalyst packed layer 4 are partitioned by the second gas rectifying layer 6 to supply the rectified exhaust gas. Similar to the first gas rectifying layer 3, the second gas rectifying layer 6 has a finer hole than the catalyst particles, and has a pressure loss sufficient to uniformly disperse the gas in the catalyst packed layer 4, such as a sintered metal plate. A porous body made of ceramic or ceramic. In the first configuration example, the second gas rectifying layer 6 configured in a cylindrical shape is shown, but the present invention is not limited to this. By providing the second gas rectifying layer 6 having the same rectifying function not only on the first gas rectifying layer 3 on the source gas introduction side but also on the reaction gas supply side, the gas flow inside the catalyst packed layer 4 is reduced. High uniformity can be ensured.

[Other configuration examples of this device]
The cooling unit 5 a is preferably partitioned from the catalyst packed bed 4 by a cylindrical porous plate 55. As illustrated in FIGS. 4A to 4E and the enlarged view, a cooling layer 56 is formed by disposing a cylindrical porous plate 55 that partitions the periphery of the cooling portion 5a. At this time, since the cooling part 5a is not in contact with the catalyst packed bed 4, the temperature of the catalyst packed bed 4 is not directly lowered by heat conduction, and the condensed reaction product is not applied to the catalyst packed bed 4. Only the cooling effect due to the removed reaction gas with a small heat capacity is exerted. At this time, as shown in FIGS. 4 (A), (B), (D) and (E), the cooling layer 56 has a configuration in which a cylindrical porous plate 55 is arranged around each cooling unit 5a and is partitioned, As shown in FIG. 4C, the four cooling parts 5a arranged concentrically are arranged concentrically so as to be sandwiched between two large cylindrical perforated plates 55, or a plurality of cooling parts 5a are provided. It can be formed by a configuration (not shown) arranged concentrically and arranged concentrically and partitioned so as to be sandwiched by the cylindrical perforated plate 55 from the upstream and downstream sides thereof.

  The cylindrical perforated plate 55 constituting the cooling layer 56 is a cylindrical perforated plate having pores smaller than the catalyst particles, and is installed along the axial direction M so as to partition the cooling unit 5 a and the catalyst packed layer 4. For example, a punching metal having an aperture ratio of 40% having a hole of φ4 mm is used. The gas flow direction and the cooling layer 56 partitioned by the cylindrical perforated plate 55 intersect each other in the vertical direction, so that the gas reliably flows through the catalyst packed layer 4. Such a cooling layer 56 has a function of relaxing heat exchange between the catalyst packed layer 4 and the cooling unit 5a, and also prevents the condensate from adhering to the catalyst. The upper end portion of the cylindrical perforated plate 55 is located on the same plane as or higher than the end portion of the catalyst packed layer 4, so that the catalyst does not flow into the cooling layer 56. The lower end portion of the cylindrical perforated plate 55 is located on the same plane as or below the lower end portion of the catalyst packed layer 4.

  In the first configuration example, the catalyst packed bed 4 has one delivery part 5, but the invention is not limited to this, and the arrangement and quantity of the delivery part 5 and the catalyst packed layer 4 are arbitrarily included. It is possible to configure. Specifically, as illustrated in FIGS. 4A to 4C, by arranging the four supply portions 5 concentrically, the catalyst filling that is concentric with the catalyst filling layer 41 outside the concentricity is arranged. The layer 42 can be divided (second configuration example). Further, as illustrated in FIGS. 4D and 4E, by disposing twelve feeding portions 5 concentrically, the catalyst packed bed 41 in the foremost stage and the catalyst packed bed 42 in the middle stage and It can be divided into the catalyst packed bed 43 in the most rear stage (third configuration example). At this time, the reaction product synthesized in the catalyst packed bed in the preceding stage is condensed and extracted by the delivery unit 5, whereby the synthesis reaction in the catalyst packed bed in the subsequent stage is promoted and a higher yield can be obtained. . Further, as can be seen from the estimation results described later, the number of catalyst packed beds is preferably about 2 to 4 in consideration of the balance between reaction efficiency and reactor size.

  The arrangement and dimensions of the delivery part 5 and the catalyst packed bed 4 are determined from the reaction conditions (gas amount, gas concentration, pressure) and economical conditions (reactor tower diameter, height).

  Further, by applying this apparatus 1, as shown in FIG. 4 (F), a baffle plate 5c for shielding gas flow is installed between cylindrical perforated plates 55 arranged concentrically at intervals. (Fourth configuration example). A baffle plate 5c is installed so as to be connected to the cylindrical porous plates 55, and the gas flow between them is blocked. Thereby, the synthesized gas containing methanol is surely guided to the cooling layer 56 through the plurality of cylindrical perforated plates 55, the contact efficiency between the gas and the cooling unit 5a is improved, and the reaction is generated inside the apparatus 1. The amount of condensed matter can be improved, leading to an improved reaction rate. Other structures and functions are the same as those of the reactor shown in the first configuration example.

<Reaction product production method using this apparatus>
Next, the reaction product manufacturing method using this apparatus 1 will be described in detail. In the present apparatus 1, the introduced raw material gas reacts and is supplied as a reaction gas, and the reaction product is extracted as a condensate. That is, a raw material gas is introduced in a direction perpendicular to the axial direction of the reactor, a part of the reaction product generated by the synthesis reaction of the catalyst packed bed is condensed on the outer periphery of the triple tube, and the condensed reaction product is The catalyst is extracted outside the reactor, and the synthesis reaction in the catalyst packed bed at the subsequent stage is promoted by improving the partial pressure of the raw material gas. Hereinafter, as an example, the reaction product manufacturing apparatus illustrated in FIG. 5 is provided with a reactor according to the first configuration example, in which the source gas is mainly composed of H _2, CO, and CO ₂ , the reaction product is methanol. The methanol synthesis process using (hereinafter referred to as “the present production apparatus”) will be described. The present manufacturing apparatus includes the apparatus 1, a flow path for introducing extracted gas containing methanol extracted from the supply unit 5 into the gas-liquid separator 8 and separating it into liquid methanol and supply gas, and a gas discharge unit The exhaust gas discharged from 7 is introduced into the condenser 9 and the gas-liquid separator 10 to condense and separate the methanol contained in the exhaust gas, and the exhaust gas after the methanol is separated is used as the feed gas. It has a channel to mix.

(1) Introduction of source gas A source gas mainly composed of H _2, CO, and CO ₂ is introduced into the apparatus 1 through the gas introduction unit 2. At this time, the raw material gas is adjusted to 180 to 300 ° C. (desirably 190 to 230 ° C.) and 1 to 15 MPa (desirably 2 to 8 MPa), adjusted to a predetermined flow rate, and then introduced. _Preferably, H 2 10~80%, a gas containing _CO5~40%, CO 2 _5~30%.

(2) Rectification of source gas The introduced source gas is uniformly dispersed in the first gas rectification layer 3 and introduced into the catalyst packed layer 4 in a direction perpendicular to the axial direction M. By rectifying and circulating from the entire outer periphery of the apparatus 1 toward the center, the uniformity can be improved.

(3) Methanol synthesis reaction The raw material gas uniformly dispersed and introduced into the catalyst packed bed 4 reacts according to the above-described reaction formulas 1 to 3, and becomes a reaction gas containing methanol. As described above, when a general copper-zinc solid methanol synthesis catalyst is used, the reaction rate in the catalyst packed bed 4 can be maximized by maintaining the reaction temperature at 200 to 230 ° C.

(4) Cooling of the reaction gas The reaction gas is transferred from the catalyst packed bed 4 to one or more delivery parts 5 and cooled by the cooling part 5a constituting the delivery part 5, and a part of methanol in the reaction gas is cooled. It condenses on the surface of the part 5a. Specifically, the cooling conditions are such that the surface of the cooling part 5a is at a temperature lower than the dew point of methanol, and the catalyst packed layer 4 is maintained at an appropriate temperature range of 170 to 250 ° C. (preferably 190 to 250 ° C.). Conditions.

(5) Delivery of reaction gas The reaction gas obtained by separating the methanol condensed in the delivery unit 5 is delivered to the outside of the apparatus 1 through the second gas rectifying layer 6 and the gas discharge unit 7. When a plurality of delivery parts 5 are arranged, the reaction gas obtained by separating the methanol condensed in the delivery part 5 at the front stage is introduced into the next catalyst packed bed 4 and further contains a new methanol by a synthesis reaction. The gas is formed and introduced into the next delivery unit 5, and the cooling of the reaction gas and the delivery of condensed methanol are repeated. The reaction gas flowing through the last delivery unit 5 is delivered to the outside of the apparatus 1 as exhaust gas through the second gas rectifying layer 6 and the gas discharge unit 7.

(6) Condensation / extraction of methanol As in (4) above, methanol in the reaction gas condenses on the surface of the cooling unit 5a. The condensed methanol gradually increases from minute droplets to become a condensate, flows down along the cooling part 5a, and is extracted from the supply part 5 through the tip part 52a. In the present apparatus 1, methanol can be efficiently condensed by the feeding section 5 having an appropriate arrangement, so that a high recovery rate can be ensured.

(7) Separation of methanol in the extracted gas The extracted gas from the supply unit 5 is introduced into the gas-liquid separator 8 and separated into liquid methanol and supply gas. The separated crude methanol is stored in a predetermined amount in the gas-liquid separator 8, and is then extracted out of the system by opening the lower on-off valve V1.

(8) Separation of methanol in exhaust gas The exhaust gas from the gas discharge section 7 is introduced into the gas-liquid separator 10 after condensing methanol in the exhaust gas by the condenser 9 and liquid methanol (crude methanol) and Separated into exhaust gas. The separated crude methanol is stored in the gas-liquid separator 10 in a predetermined amount, and then extracted from the system by opening the lower on-off valve V2. The crude methanol extracted out of the system is mixed with the methanol extracted from the gas-liquid separator 8 and then used as product methanol via a separate purification process.

(9) Delivery of delivery gas and exhaust gas The delivery gas from the gas-liquid separator 8 is decompressed to atmospheric pressure by the decompression valve V3, and then adjusted to a predetermined flow rate by the flow control valve V4. On the other hand, the exhaust gas from the gas-liquid separator 10 is depressurized to the atmospheric pressure by the pressure reducing valve V5. The flow-adjusted exhaust gas and supply gas can be mixed and then used as gas power generation or fuel, or recycled to the methanol production system.

  As described above, in this methanol synthesis method, a high conversion rate exceeding the equilibrium conversion rate can be ensured by sequentially recovering methanol from the upstream of the catalyst packed bed 4 by one or a plurality of delivery parts 5. An unprecedented high methanol yield can be obtained.

[Example 1]
The structure of the cooling unit in the reactor has a great influence on the catalyst packed bed. Here, the temperature distribution in the catalyst packed bed was verified and its technical effect was verified.

(1) Experimental apparatus The temperature distribution in the vertical direction in the catalyst packed bed was verified for the reactor according to the present configuration example shown in FIG. 6A and the conventional configuration example shown in FIG. In the conventional configuration example, two cooling pipes R5 are inserted vertically from the top of the reactor R1 to the bottom of the reactor R1 in the catalyst packed bed R4, and the methanol condensed inside the reactor R1 is placed on the outer surface of the cooling pipe R5. And then discharged from the bottom of the reactor R1. On the other hand, in this configuration example, four triple-tube type cooling pipes 5 are inserted from the upper part of the reactor 1 to the intermediate height of the catalyst packed bed 4. The mecanol condensed inside the reactor 1 flows down along the outer surface of the cooling pipe 5 and is discharged from the upper end of the reactor 1 through the inside of the cooling pipe 5 together with the extracted gas from the lower end of the cooling pipe 5. The inner diameter of the tube through which the extracted gas at the center of the triple tube type cooling tube 5 flows is 2 mm.

(2) _the composition of the experimental conditions the reactor inlet of the raw material _{gas, H 2 14~20%, CO8~11%} , CO 2 15~20%, Others _{(N 2)} and 50 to 60% The ingredients, gas supply flow rate Was about 50 m ³ N / h, the gas pressure was 4-5 MPa, and the gas temperature was 200-240 ° C. and introduced into the reactor. Cooling water is used as the cooling medium (cooling water temperature is 5 to 40 ° C.), and the flow rate of the extracted gas from the triple pipe type cooling pipe in this configuration example is 0.25 m ³ N / h per cooling pipe. .

(2) Verification result The temperature distribution pattern in the vertical direction of the catalyst packed bed is shown in FIG. The temperature measurement point was measured at the most downstream part (near the center of the reactor) of the catalyst packed bed. The two results shown in FIG. 6C are substantially equal to the catalyst packed bed downstream average temperature (the arithmetic average of the upper / middle / lower) and the reactor outlet gas temperature. However, the temperature distribution pattern is different, and in the conventional configuration example, there was a temperature difference of about 30 ° C in the vertical direction of the catalyst packed bed, but in this configuration example, the vertical temperature difference can be compressed to about 10 ° C. It was. Further, since the temperature unevenness of the catalyst packed bed could be suppressed, in this configuration example, the reaction rate was improved by about 10% compared to the conventional configuration example.

[Example 2]
Using the reactor according to this configuration example, the temperature state and reaction rate in the horizontal direction inside the reactor were verified.
(1) Experimental conditions The composition of the raw material gas was as shown in Table 1 below, and was introduced into the reactor at a gas supply flow rate of about 3.5 m ³ N / h, a pressure of 3 MPa, and a temperature of 180 to 230 ° C. Regarding the horizontal temperature distribution in the catalyst packed bed at this time, the case where the cooling part (cooling layer) was disposed in the catalyst packed layer and the case where it was not disposed were compared. A sheath tube was inserted horizontally into the reactor, and a thermocouple was inserted into it to measure the catalyst temperature distribution in the reactor. Moreover, the gas composition was measured with the micro gas chromatograph at the inlet and outlet of the reactor, and the reaction rate was measured. Here, CO conversion was used as the reaction rate. In this example, the gas flow rate is small, the heat release from the reactor is large, and the catalyst packed bed cannot be maintained at a constant temperature. To compensate.

(2) Experimental Results (2-1) Temperature Distribution FIG. 7 shows the horizontal temperature distribution in the catalyst packed bed at this time. In the thermocouple inserted in the sheath tube into the reactor where the cooling part (cooling layer) is not arranged, the catalyst temperature rises due to the reaction heat and enters the catalyst packed bed. You can see that the temperature has leveled off. That is, after that, the reaction does not proceed in the catalyst packed bed. On the other hand, in a reactor provided with a cooling layer, the temperature rise in the catalyst packed bed is slightly lower due to heat transfer from the cooling layer, and the gas is cooled in the cooling layer. confirmed. It can be seen that the catalyst temperature rises again in the catalyst packed bed after the cooling layer. That is, the reaction product methanol was separated in the cooling layer, and the chemical equilibrium was shifted to the product side, so that the reaction was also promoted in the subsequent catalyst packed bed.
(2-2) Reaction rate (CO conversion rate)
The CO conversion calculated from the gas composition measured at the inlet and outlet of the reactor was 64.6%. On the other hand, the equilibrium conversion rate of the reactor inlet gas composition at the catalyst packed bed outlet temperature is 53.7%, indicating that the reaction rate exceeding the chemical equilibrium value is achieved. At this time, the amount of methanol condensed and recovered in the reactor was 51.3% of the methanol produced by the reaction (gas flow rate × inlet CO concentration × CO conversion rate).

Example 3
By condensing the reaction product (methanol) inside the reactor and separating it outside the reaction system, the chemical equilibrium of the above reaction formulas 1 to 3 moves. Here, the technical effect of moving the chemical equilibrium was verified by chemical equilibrium calculation.
(1) Verification conditions The gasification gas (gasification agent: air and water vapor | steam) of wood type biomass was used as raw material gas. The gas composition is shown in Table 2 below. The pressure of the methanol synthesis reaction was 4.0 MPa, and it was assumed that the reaction proceeded to a chemical equilibrium value at a reaction temperature of 493.15 K in the catalyst packed bed. Using the reactor shown in the third configuration example, Trial Calculation Example 1 has three catalyst packed layers (two cooling layers), and the methanol condensation rate in the cooling layer (the ratio of the amount of condensed methanol to the amount of generated methanol) is 0. It is a case where it is set to ˜50% (0% is a chemical equilibrium value). Trial calculation example 2 is a case where the reactor shown in the first configuration example is used and two catalyst packed layers (one cooling layer) are used.

(2) Verification Results FIG. 8 shows the reaction rate at this time (CO conversion rate = ratio of conversion to methanol out of the amount of CO at the reactor inlet) for trial calculation examples 1 and 2. It was found that a high reaction rate with respect to the chemical equilibrium value can be obtained by condensing and extracting methanol, which is a reaction product, in the reactor. It was also found that higher yields can be achieved by installing multiple stages of cooling layers.

Example 4
Next, the effect of separating reaction products and shifting chemical equilibrium based on the reaction rate analysis and the effect of providing a plurality of catalyst packed layers by providing cooling layers will be described. Using the reaction rate coefficient obtained from the experiment, the temperature distribution of the reactor and the CO conversion rate were estimated from the reaction rate equation.
(1) Trial calculation conditions The supply conditions of the raw material gas are as shown in Table 2 below.

(2) Trial Calculation Results FIG. 9 shows the temperature distribution in the reactor and the CO conversion rate when the length of the catalyst packed bed is taken on the horizontal axis. As the process proceeds to the subsequent stage, the partial pressure of the raw material gas decreases, so that the reaction rate gradually decreases. However, it can be seen that the reaction rate greatly increases through a plurality of catalyst packed layers. As described above, an increase in the number of catalyst packed beds means that the tower diameter of the reactor increases, and the pressure-resistant portion of the pressure vessel increases in thickness as the tower diameter increases. Lead to increased manufacturing costs. Therefore, considering the trial calculation results, it can be said that the number of catalyst packed beds is preferably about 2 to 4 from the relationship between reaction efficiency and reactor tower diameter.

As described above, the embodiment of the present invention has been described with reference to a methanol synthesis process using biomass or the like as a raw material, but objects to which the present invention can be applied are not limited to these, It is preferable to apply to a reaction process that satisfies the following points.
(I) Being a gas phase reaction (ii) Being a reversible reaction (iii) Cooling causes reaction products to condense, and there are operating conditions in which reactants and reaction intermediates do not condense (iv) Being an exothermic reaction, for example, it can be applied to various processes in which a reaction product can be extracted by a plurality of cooling layers using a catalyst packed bed. In particular, it can be used for FT synthesis process, ethanol synthesis process and the like.

1 Reactor (this device)
1a, 1c annular end 1b reactor body (body)
2 Raw material gas introduction part (gas introduction part)
2a Raw material gas inlet 3 First gas rectifying layer 4 Catalyst packed layer 4a Catalyst filled port 4b Catalyst outlet 5 Reaction product delivery part (delivery part)
5a Reaction product cooling section (cooling section)
5b Reaction product extraction part (extraction part)
50 Triple pipe 51 Outer pipe 52 Inner pipe 53 Middle pipe 51a, 52a, 53a Outer peripheral part 51b, 52b, 53b Flow path 52c Tip 6 Second gas rectifying layer 7 Reactive gas discharge part (gas discharge part)

Claims (7)

In a reactor having a raw material gas introduction part, a catalyst packed bed, a reaction product delivery part and a reaction gas discharge part, and a reaction product is produced by catalytic reaction,
The raw material gas introduction part is provided in the body part of the reactor,
A reaction gas discharge part is provided in the central shaft part of the reactor,
The reaction product delivery part is inserted from the upper end of the reactor, and a reaction product cooling part that forms a triple tube in part, and a reaction product in which a part of the reaction product is extracted from the upper part of the reactor It is configured as a unit from the object extraction part,
The triple pipe is an outer pipe through which a cooling medium is introduced and circulated, an inner pipe provided inside the outer pipe from which a part of the reaction product is extracted, and an outer circumference of the inner pipe. An inner pipe provided inside the outer pipe and through which the cooling medium is circulated and discharged,
A reactor characterized in that a tip portion of the inner tube is located at an approximate center from an upper part inside the reactor.   The outer peripheral portion of the triple tube inserted in the reactor is gradually reduced in outer diameter or partially having the same diameter portion, and at the distal end portion of the inner tube, on the central axis of the inner tube. The reactor according to claim 1, wherein the reactor has a vertical flat surface.   3. The reactor according to claim 1, wherein the reaction product supply section includes a cylindrical porous plate that partitions the periphery of the triple tube, and a plurality of the reaction product supply sections are arranged concentrically in the catalyst packed bed.   The reactor according to any one of claims 1 to 3, wherein the source gas introduction part and the catalyst-filled layer are partitioned by a gas rectifying layer, and the rectified source gas is introduced to the catalyst-packed layer.   The reactor according to any one of claims 1 to 4, wherein the reaction gas discharge part and the catalyst-filled layer are partitioned by a gas rectifying layer to enhance the uniformity of the gas flow inside the catalyst-filled layer.   The reactor according to any one of claims 1 to 5, wherein a shielding plate for restricting the flow of gas is disposed in the catalyst packed bed to enhance the contact efficiency between the gas and the cooling pipe.   A reaction product production method using the reactor according to any one of claims 1 to 6, wherein the reaction is performed by introducing a raw material gas in a direction perpendicular to the axial direction of the reactor and by a synthesis reaction of the catalyst packed bed. A part of the product is condensed on the outer periphery of the triple tube, and a part of the condensed reaction product is extracted to the outside of the reactor, and the partial pressure of the reaction product is reduced to reduce the partial pressure of the reaction product. A method for producing a reaction product, characterized in that the synthesis reaction is accelerated.

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