Flow reactor, method for cleaning the flow reactor, and method for producing reaction products

Abstract

The present invention provides a method for cleaning a flow-type reaction apparatus that produces a reaction product by bringing two or more raw materials into contact, and a method for producing the reaction product. [Solution] The cleaning method for the reaction apparatus 100 includes a first cleaning step of supplying cleaning liquid and inert gas to the reaction section M, a second cleaning step performed after the first cleaning step of supplying only cleaning liquid to the reaction section M, a third cleaning step performed after the second cleaning step of allowing the cleaning liquid to remain in the reaction section M, a fourth cleaning step performed after the third cleaning step of replacing the cleaning liquid remaining in the reaction section M with new cleaning liquid, and a fifth cleaning step performed after the fourth cleaning step of reducing the concentration of the cleaning liquid remaining in the reaction section M. In the first cleaning step, the cleaning liquid is supplied via the first line 1 and the inert gas is supplied via the second line 2, thereby supplying the cleaning liquid and inert gas simultaneously and allowing the reaction section M to flow in a gas-liquid mixed phase flow state.

Description

Technical Field

[0001] The present invention relates to a flow-type reactor, a cleaning method for the flow-type reactor, and a method for producing a reaction product.

Background Art

[0002] Conventionally, the production of reaction products (chemical substances) by chemical reactions has generally been carried out using batch-type reactors. However, when producing reaction products using a batch-type reactor, it is necessary to sufficiently stir and mix the reaction target (raw material) in the reaction tank where the chemical reaction occurs (for example, until molecular diffusion is achieved), which may result in a longer reaction time and a decrease in production efficiency. In addition, in a batch-type reactor, it may be difficult to control the chemical reaction when increasing the batch size.

[0003] For such batch-type reactors, in a flow-type reactor that continuously supplies raw materials and continuously obtains reaction products, the production efficiency can be improved compared to using a batch-type reactor, and the control of chemical reactions may also become easier. In addition, since a flow-type reactor can easily set extreme reaction conditions (for example, high temperature or high pressure), it may be possible to cause chemical reactions that are difficult to control in a batch-type reactor. In addition, a flow-type reactor is easy to stop and restart production. In addition, a flow-type reactor has the characteristics that the scale during a disaster is small, scale-up is easy, it is excellent in thermal efficiency, and the equipment cost is low.

[0004] Therefore, in recent years, the production of reaction products using a flow-type reactor has attracted attention (for example, see Patent Document 1). In addition, for the purpose of improving productivity and workability, the number of cases of stationary cleaning of reactors has been increasing (for example, see Patent Document 2). In stationary cleaning, for example, liquid flow cleaning in which a cleaning liquid is passed through pipes and the like is performed.

[0005] Patent Document 1 discloses a flow-type reactor for continuously reacting two or more raw material substances. This flow-type reactor comprises a mixing section for mixing two or more raw material substances, and a reaction section located on the secondary side of the mixing section, which reacts the raw material substances to obtain a product. The mixing section has a mixer for mixing two or more raw material substances, and two or more supply paths for supplying each raw material substance to the mixer. Two supply paths are connected to the mixer, and one of the supply paths supplies from the mixer to the vicinity of the connection point between that supply path and the mixer. It has a suppression mechanism that inhibits the movement of fluid towards the path.

[0006] Patent Document 2 describes a method for cleaning polymer piping through which a polymer solution is passed. In this cleaning method, polymer piping cleaning solution, which consists of a solution with a high concentration of soluble evaporation residue, is passed through the polymer piping to remove polymer adhering to the inside of the polymer piping and clean it. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2019-98275 [Patent Document 2] Japanese Patent Publication No. 2017-196567 [Overview of the project] [Problems that the invention aims to solve]

[0008] Because flow reactors continuously supply raw materials and continuously produce (manufacture) reaction products, the piping through which raw materials and reaction products flow, as well as the piping that causes the chemical reaction, is designed to prevent stagnation and accumulation of raw materials and products, thus minimizing blockages. However, these pipes usually need to be cleaned at predetermined intervals. Furthermore, blockages may occur in the piping due to changes in the surrounding environment or human error, necessitating cleaning of these pipes. When such cleaning is performed by disassembling and cleaning the flow reactor, disassembly and reassembly can be time-consuming, and there is a risk of damaging the piping and instruments of the flow reactor due to human error during disassembly and reassembly. Therefore, there is a need for a method of cleaning flow reactors without disassembly (a so-called stationary cleaning method).

[0009] However, conventional liquid-flow cleaning methods for stationary cleaning, as exemplified in Patent Document 2, are designed for single piping and may not provide sufficient cleaning effect in flow-type reactors that produce reaction products by bringing two or more raw materials into contact. Therefore, there is a need for a stationary cleaning method suitable for flow-type reactors.

[0010] The present invention has been made in view of the above circumstances, and its object is to provide a flow-type reactor that produces a reaction product by contacting two or more raw materials, a flow-type reactor that can be cleaned in place, a method for cleaning the flow-type reactor, and a method for producing the reaction product. [Means for solving the problem]

[0011] The flow-type reaction apparatus according to the present invention, for achieving the above objective, A mixing section is provided for mixing the fluid of a first raw material and the fluid of a second raw material, and a reaction section is provided for continuously generating reaction products by continuously chemically reacting the first raw material and the second raw material, A first line is a pipe that supplies the first raw material to the reaction section, A second line is a pipe that supplies the second raw material to the reaction section, The system includes a cleaning line which is a pipe that supplies cleaning liquid to the reaction section, The washing line is connected to the first line or the second line.

[0012] To achieve the above objective, the cleaning method for the flow-type reactor according to the present invention is: A first cleaning step involves supplying a cleaning solution and an inert gas to the reaction section, A second cleaning step is performed after the first cleaning step, in which only cleaning solution is supplied to the reaction section. A third cleaning step is performed after the second cleaning step, in which the cleaning solution is retained in the reaction section. A fourth cleaning step is performed after the third cleaning step, in which the cleaning solution remaining in the reaction section is replaced with a new cleaning solution. The process includes a fifth cleaning step, which is performed after the fourth cleaning step, to reduce the concentration of the cleaning solution remaining in the reaction section.

[0013] The method for producing the reaction product according to the present invention, which achieves the above objective, A reaction process in which a first raw material and a second raw material are continuously chemically reacted using the flow-type reactor described above to continuously produce a reaction product, This includes a stationary cleaning step for the flow-type reactor. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a flow-type reactor that produces a reaction product by bringing two or more raw materials into contact, a flow-type reactor that can be cleaned in place, a method for producing a reaction product using the flow-type reactor, and a method for cleaning the flow-type reactor. [Brief explanation of the drawing]

[0015] [Figure 1] Flow-type reactor according to this embodiment. This is a flow diagram according to this embodiment. [Figure 2] This is a diagram illustrating the connection status of the washing line to the first line. [Figure 3]This is a photograph showing the state of the joint before cleaning. [Figure 4] This is a photograph showing the state of the joint after cleaning.

Embodiments for Carrying Out the Invention

[0016] While referring to the drawings, a flow-type reactor according to an embodiment of the present invention, a cleaning method for the flow-type reactor, and a method for producing a reaction product will be described.

[0017] (Explanation of the Outline) FIG. 1 shows a flow diagram of a flow-type reactor 100 (hereinafter referred to as the reactor 100) according to the present embodiment.

[0018] First, an outline of the reactor 100, a cleaning method for the reactor 100, and a method for producing a reaction product using the reactor 100 will be described.

[0019] As shown in FIG. 1, the reactor 100 has a mixing section 41 that mixes the fluid of the first raw material and the fluid of the second raw material, and a reaction section M that continuously chemically reacts the first raw material and the second raw material to continuously produce a reaction product, a first line 1 that is a pipe for supplying the first raw material to the reaction section M, a second line 2 that is a pipe for supplying the second raw material to the reaction section M, and a cleaning line 3 that is a pipe for supplying a cleaning liquid to the reaction section M. The cleaning line is connected to the first line 1.

[0020] The cleaning method for the reactor 100 according to the present embodiment includes a first cleaning step of supplying a cleaning liquid and an inert gas to the reaction section M, a second cleaning step that is performed after the first cleaning step and supplies only the cleaning liquid to the reaction section M, a third cleaning step that is performed after the second cleaning step and retains the cleaning liquid in the reaction section M, a fourth cleaning step that is performed after the third cleaning step and replaces the cleaning liquid retained in the reaction section M with a new cleaning liquid, and a fifth cleaning step that is performed after the fourth cleaning step and reduces the concentration of the cleaning liquid retained in the reaction section M.

[0021] The reaction apparatus 100 can implement a reaction process in which a reaction product is continuously generated by chemically reacting the first raw material and the second raw material, and a stationary cleaning process using the cleaning method described above.

[0022] In other words, the reaction apparatus 100 can provide a method for producing a reaction product by bringing two or more raw materials into contact. Furthermore, the reaction apparatus 100 implements stationary cleaning for the reaction section M and other components that are required periodically during the production of the reaction product, thereby improving the efficiency of the production of the reaction product.

[0023] In the reactor 100, for example, the effort required for disassembling and reassembling the reactor 100 for cleaning can be reduced. In addition, the risk of damage to the piping and instruments of the reactor 100 due to human error during this disassembly and reassembly can be avoided.

[0024] The following describes the details of each part of the reaction apparatus 100 and the cleaning method (stationary cleaning) for the reaction apparatus 100.

[0025] (Description of the reaction apparatus) The reaction apparatus 100 is a continuous chemical reaction apparatus that produces a reaction product by continuously chemically reacting a first raw material with a second raw material. In the following explanation, we will use the case where the first raw material is in liquid form (an example of a fluid) and the second raw material is in gaseous form (an example of a fluid) as an example.

[0026] In addition to the reaction section M having a mixing section 41, the first line 1, the second line 2, and the washing line 3 described above, the reaction apparatus 100 is equipped with a raw material tank 10 (hereinafter referred to as tank 10), such as a storage tank for storing the first raw material, a cylinder 20, such as a gas cylinder for storing the second raw material, and a washing tank 30 (hereinafter referred to as tank 30), such as a storage tank for storing the washing liquid.

[0027] The first line 1 is a piping system that supplies the first raw material to the mixing unit 41. The first line 1 receives the first raw material from the tank 10 and supplies it to the mixing unit 41.

[0028] In the first line 1, a liquid transfer pump 11 (hereinafter referred to as pump 11), a valve 71, a filter 12, a junction 17 to which valve 72 is connected, and a flow meter 13 are provided in this order between the tank 10 and the mixing section 41.

[0029] The first line 1 only needs to be formed from a material that is chemically stable with respect to the first raw material and cleaning solution. Materials such as stainless steel and fluororesins (PTFE or PFA) can be used to form the first line 1.

[0030] Pump 11 is a liquid transfer device in the first line 1 that draws up the first raw material from the tank 10 and sends it to the mixing section 41. Pump 11 may be, for example, a turbine pump, gear pump, diaphragm pump, tube pump, plunger pump, etc.

[0031] Filter 12 is a filtration device that filters the first raw material flowing through the first line 1 to capture solid matter.

[0032] The flow meter 13 is a flow measuring device that measures the flow rate of the first raw material flowing through the first line 1. An example of the flow meter 13 is a mass flow meter for liquids.

[0033] The junction 17 is a junction piping section where the cleaning line 3 (valve 72) merges with the first line 1. Valve 72 is a valve device that allows or prohibits the introduction of cleaning fluid from cleaning line 3 into the first line 1. Valve 72 is provided in cleaning line 3, which will be described later. Valve 72 may be, for example, a diaphragm valve, a ball valve, or a butterfly valve.

[0034] Valve 71 is a valve device that allows or prohibits the discharge of liquid (e.g., first raw material or cleaning liquid) flowing through the first line 1 to the outside of the system (reaction apparatus 100). Valve 71 may be connected to, for example, a drain pipe of a cleaning liquid discharge line that discharges cleaning liquid to the outside of the system. Valve 71 may be, for example, a diaphragm valve, a ball valve, or a butterfly valve.

[0035] The second line 2 is a piping system that supplies the second raw material to the mixing unit 41. The second line 2 receives the second raw material from the cylinder 20 and supplies it to the mixing unit 41.

[0036] In the second line 2, a pressure regulating valve 21, a valve 73, a valve 74, and a flow meter 23 are installed in this order between the cylinder 20 and the mixing unit 41.

[0037] The second line 2 only needs to be formed from a material that is chemically stable with respect to the second raw material and cleaning solution. Materials such as stainless steel and fluororesins (PTFE or PFA) can be used to form the second line 2.

[0038] The pressure regulating valve 21 is a valve device that adjusts the pressure of the second raw material discharged from the cylinder 20 to a predetermined pressure and sends it to the mixing section 41. The pressure regulating valve 21 is, for example, a pressure reducing valve.

[0039] The flow meter 23 is a flow measuring device that measures the flow rate of the second raw material flowing through the second line 2. An example of the flow meter 23 is a mass flow meter for gases.

[0040] Valve 73 is a valve device that allows or prohibits the supply of the second raw material from cylinder 20 to the second line 2. Valve 73 may be, for example, a diaphragm valve, a ball valve, a butterfly valve, or a needle valve.

[0041] Valve 74 is a valve device that allows or prohibits the introduction of a cleaning gas (e.g., an inert gas such as nitrogen) into the second line 2. Valve 74 may be connected to, for example, a nitrogen cylinder or an inert gas generator, and the inert gas may be supplied from the nitrogen cylinder or the like as the cleaning gas. Valve 74 may be, for example, a diaphragm valve, a ball valve, or a butterfly valve.

[0042] The cleaning line 3 is a piping system that supplies cleaning fluid to the first line 1. The cleaning line 3 receives cleaning fluid from the tank 30 and supplies it to the first line 1. In this embodiment, the cleaning line 3 is connected to the junction 17 of the first line 1 via a valve 72.

[0043] The cleaning line 3 is preferably connected to the first line 1 in a vertically downward direction. Specifically, as shown in Figure 2, the cleaning line 3 is connected such that the piping portion of the cleaning line 3 adjacent to the valve 72 becomes a downward-extending piping section 3a, so that the cleaning fluid flows vertically downward at the confluence section 17, which is the connection point to the first line 1. This suppresses the residue of cleaning fluid in the cleaning line 3 (especially the downward-extending piping section 3a) after cleaning, as will be described later. The internal piping of the valve 72 is also preferably arranged vertically downward. Alternatively, the entire cleaning line 3 may be arranged vertically downward. In Figure 2, the upward direction in the vertical direction is shown as direction G1, and the downward direction in the vertical direction is shown as direction G2. In the example shown in Figure 2, the flow meter 23 is positioned vertically below the filter 12 side of the first line 1, but the piping arrangement of the first line 1 is not limited to this example.

[0044] The cleaning line 3 shown in Figure 1 only needs to be formed from a material that is chemically stable in the cleaning solution. Materials such as stainless steel and fluororesins (PTFE or PFA) can be used to form the cleaning line 3.

[0045] In the cleaning line 3, a cleaning pump 31 (hereinafter referred to as pump 31) and a valve 75 are installed in this order between the tank 30 and the valve 72.

[0046] Pump 31 is a fluid delivery device in the cleaning line 3 that draws up cleaning fluid from tank 30 and sends it to valve 72. Pump 31 may be a turbine pump, gear pump, diaphragm pump, tube pump, plunger pump, etc.

[0047] Pump 31 should be capable of delivering the cleaning solution at a flow rate of approximately 10 to 1000 ml / min (for example, when the pipe diameter of the first line 1 is 6.35 mm). Pump 31 should also be capable of delivering the cleaning solution at a liquid pressure of approximately 0 to 0.5 MPa (gauge pressure). Typically, pump 31 only needs to be able to deliver the cleaning solution at 0.1 to 0.3 MPa (gauge pressure).

[0048] Valve 75 is a valve device that allows or prohibits the introduction of cleaning gas (e.g., an inert gas such as nitrogen) into the cleaning line 3. Valve 75 may be connected to, for example, a nitrogen cylinder or an inert gas generator, and the inert gas may be supplied from the nitrogen cylinder or the like as the cleaning gas. Valve 75 may be, for example, a diaphragm valve, a ball valve, or a butterfly valve.

[0049] The reaction unit M is a unit having a tubular reactor 42 (hereinafter referred to as reactor 42) that continuously chemically reacts a first raw material with a second raw material to produce a reaction product. In addition to the mixing unit 41 and reactor 42 described above, the reaction unit M has a separation and recovery device 50 (hereinafter referred to as recovery device 50) for recovering the reaction product, and piping 4 that connects the mixing unit 41, reactor 42, pressure relief valve 43, and recovery device 50 in that order.

[0050] The mixing unit 41 is a mixing mechanism that receives the first and second raw materials supplied from the first line 1 and the second line 2, and sends a mixed gas-liquid multiphase flow (e.g., slug flow) to the reactor 42. The mixing unit 41 may be, for example, a static mixer or equipped with a venturi mechanism. The first and second raw materials are continuously supplied to the mixing unit 41, for example, in a constant ratio. The multiphase flow is sent from the mixing unit 41 to the reactor 42, for example, at a constant flow rate.

[0051] Reactor 42 is a tubularly shaped reaction field designed to ensure sufficient reaction time for the gas-liquid multiphase flow (first raw material and second raw material) formed in the mixing section 41 to complete its chemical reaction. In reactor 42, a predetermined reaction product is produced by this chemical reaction.

[0052] The reactor 42 may be formed, for example, by a coil-shaped tube with an inner diameter such that the gas-liquid multiphase flow described above does not separate, and an appropriate shear force is generated between the tube wall and the gas-liquid multiphase flow as it passes through the tube of the reactor 42, thereby maintaining a mixed state (multiphase state).

[0053] The reactor 42 is preferably formed from narrow piping of 1 / 4 inch or less. This reduces the influence of gravity on the gas-liquid multiphase flow passing through the piping that constitutes the reactor 42, allowing the first and second raw materials to mix while maintaining a state in which they are alternately divided into small segments (slug flow). As a result, high mixing uniformity can be achieved immediately in this gas-liquid multiphase flow.

[0054] The reaction time in reactor 42 can be arbitrarily adjusted, for example, by the diameter and length of the tube. For example, by making the tube length of reactor 42 sufficiently long, the chemical reaction can proceed sufficiently to improve the yield of the reaction product and to obtain a chemically stable compound as the reaction product. Alternatively, by shortening the tube length of reactor 42, a chemically unstable compound can be obtained as the reaction product.

[0055] The flow rate of the gas-liquid multiphase flow supplied to the reactor 42 can be adjusted by controlling the output of the pump 11 on the first line 1 and the regulated pressure at the pressure regulating valve 21 on the second line 2 to control the supply flow rates of the first and second raw materials.

[0056] The pressure of the gas-liquid multiphase flow supplied to the reactor 42 (the reaction pressure inside the reactor 42) can be controlled by adjusting the output of the pump 11 on the first line 1, the regulated pressure at the pressure regulating valve 21 on the second line 2, and the opening degree or set pressure of the pressure relief valve 43.

[0057] In reactor 42, the reaction temperature may be adjusted (controlled) by heating or cooling the piping as needed.

[0058] From the reactor 42, a fluid containing the reaction products (hereinafter referred to as the product fluid) is discharged to the recovery device 50 at a predetermined flow rate.

[0059] The recovery device 50 is a device or mechanism for recovering the reaction product produced by the reaction between the first raw material and the second raw material.

[0060] The recovery device 50 may include, for example, a recovery container 51 for storing the product fluid discharged from the reactor 42, a level sensor 52 for detecting the liquid level in the recovery container 51, and a vacuum pump 53 for reducing the pressure inside the recovery container 51. In the recovery device 50, for example, the reaction product is vaporized and separated for recovery by reducing the pressure in the recovery container 51, as will be described later, and the solvent remaining after the recovery of the reaction product (hereinafter referred to as waste liquid) is separated and discharged outside the system of the reactor 100.

[0061] A valve 76 may be provided in the piping 5a connecting the recovery container 51 and the pressure reducing pump 53 to allow or prohibit the outflow of gas from the recovery container 51 to the pressure reducing pump 53. The piping 5a is preferably connected to the top of the recovery container 51.

[0062] A pipe 5b for discharging liquid (solvent or cleaning solution) from the recovery container 51 may be connected to the bottom of the recovery container 51. The pipe 5b may be provided with a valve 77 for allowing or prohibiting the outflow of liquid from the recovery container 51, and valves 78 and 79 for discharging the liquid that has passed through valve 77 to the outside. Valve 78 may be connected to, for example, a drain pipe of a cleaning solution discharge line that discharges cleaning solution outside the system. Valve 79 may be connected to, for example, a waste liquid pipe of a waste liquid line that discharges waste liquid outside the system. Valves 77, 78 and 79 may be, for example, diaphragm valves, ball valves or butterfly valves.

[0063] As described above, the recovery device 50 recovers the reaction products by vaporizing them by reducing the pressure in the recovery container 51, for example. Specifically, for example, the vacuum pump 53 is driven to reduce the pressure inside the recovery container 51, and the gas inside (reaction products in this example) is exhausted from the upper region of the recovery container 51 through the piping 5a to the outside of the recovery container 51 (outside the system of the reaction device 100, for example, to a product tank).

[0064] In the recovery device 50, for example, if the level sensor 52 detects that the product fluid has accumulated in the recovery container 51 to a predetermined liquid level, the supply of the first and second raw materials from the first line 1 and the second line 2 to the reaction section M in the reaction device 100 may be stopped. Alternatively, upon such detection, valves 77 and 79 may be opened to discharge the waste liquid outside the system.

[0065] (Explanation regarding stationary cleaning) The following describes the stationary cleaning of the reaction apparatus 100 using cleaning fluid supplied from cleaning line 3 and inert gas supplied from valve 74.

[0066] As described above, the cleaning line 3 is connected to the first line 1 via the valve 72. This allows the cleaning line 3 to supply cleaning fluid between the pump 11 and the mixing unit 41 in the first line 1.

[0067] In this way, by supplying cleaning fluid from the cleaning line 3 between the pump 11 and the mixing unit 41 in the first line 1, the mixing unit 41, reactor 42, and pressure relief valve 43, as well as the piping 4 connecting them, which are highly likely to become clogged in the reactor 100, can be cleaned particularly efficiently. Specifically, the cleaning fluid can be flowed from the position of valve 72 toward valve 78.

[0068] In particular, by connecting the cleaning line 3 between the pump 11 and the flow meter 13, the reaction apparatus 100 can be cleaned while monitoring the flow rate of the cleaning fluid supplied from the cleaning line 3 (valve 72) to the valve 78 with the flow meter 13.

[0069] The recovery device 50 can be cleaned with cleaning fluid supplied via the piping 4. The recovery device 50 can be cleaned, for example, by allowing the cleaning fluid supplied via the piping 4 to remain in the recovery container 51. That is, the recovery device 50 can be cleaned by dissolving or washing away any residue adhering to the liquid-contacting surfaces of the recovery container 51, such as the inner wall, with the cleaning fluid remaining in the recovery container 51.

[0070] When cleaning the recovery device 50, the liquid level of the cleaning solution retained in the recovery container 51 should be set to be higher than the liquid level of the waste liquid used during manufacturing. This allows the recovery container 51 to be properly cleaned. The liquid level of the cleaning solution can be detected by the level sensor 52.

[0071] For example, when producing reaction products in the reactor 100, if the liquid level of the product fluid stored in the recovery container 51 is controlled to a height of 20% of the effective capacity of the recovery container 51, then when cleaning the recovery device 50, the liquid level of the cleaning solution retained in the recovery container 51 may be set to a height of 40% of the effective capacity of the recovery container 51.

[0072] The cleaning solution used to clean the recovery container 51 is discharged out of the system via valves 77 and 78 in the piping 5b connected to the bottom of the recovery container 51. This prevents the cleaning solution from contaminating the piping 5a, i.e., from contaminating the reaction product, which is recovered as a product via piping 5a.

[0073] In this embodiment, since the filter 12 is positioned between valve 71 and valve 72, the cleaning liquid supplied from the cleaning line 3 can pass through the filter 12 and then be discharged outside the system of the reactor 100 via valve 71. This allows the filter 12 to be cleaned by passing liquid through it without disassembling it.

[0074] In this embodiment, the cleaning liquid supplied from the cleaning line 3 flows through the filter 12 in the opposite direction to the flow direction of the first raw material. That is, the filter 12 is backwashed by the cleaning liquid. By backwashing in this way, solid matter captured by the filter 12 can be efficiently removed.

[0075] In this embodiment, as described above, the cleaning line 3 is connected vertically downward to the horizontal piping section 1a of the first line 1. Therefore, the cleaning fluid present in the piping section of the cleaning line 3, which is arranged vertically, flows into the first line 1 by gravity after the pump 31 stops. In other words, by connecting the cleaning line 3 vertically downward to the horizontal piping section 1a of the first line 1, the accumulation of cleaning fluid near the connection point between the cleaning line 3 and the first line 1 (near the valve 72) after cleaning is suppressed.

[0076] The cleaning fluid supplied from cleaning line 3 should ideally be supplied at a flow rate of approximately 10 to 1000 ml / min. The fluid pressure of the supplied cleaning fluid should be approximately 0 to 0.5 MPa (gauge pressure). Typically, a fluid pressure of 0.1 to 0.3 MPa (gauge pressure) is sufficient. The flow velocity of the cleaning fluid through the first line 1 and piping 4 should be 0.5 to 50 m / s.

[0077] When supplying the cleaning solution from the cleaning line 3, it is preferable to simultaneously introduce an inert gas from valve 74 into the second line 2 and supply the cleaning solution and inert gas to the reaction section M at the same time, as this further enhances the cleaning effect of the reaction section M (an example of the first cleaning step). When supplying the cleaning solution from the cleaning line 3, instead of introducing the inert gas from valve 74 into the second line 2, or in addition to introducing the inert gas from valve 74 into the second line 2, the inert gas may also be supplied to the reaction section M via the cleaning line 3 from valve 75.

[0078] When a cleaning solution and an inert gas are supplied simultaneously to the reaction section M, the cleaning solution and the inert gas flow through the reaction section M in a gas-liquid multiphase flow state, such as a slug flow. This causes the cleaning solution and the inert gas to collide violently with the pipe walls and inner walls of the container in the reaction section M, and also allows the cleaning solution and the inert gas to exert a large shear force on the pipe walls and inner walls of the container in the reaction section M, thereby enhancing the cleaning effect of the reaction section M. When supplying a cleaning solution and an inert gas simultaneously to the reaction section M, the flow rate ratio of the inert gas to the cleaning solution (flow rate of cleaning solution to flow rate of inert gas) should be approximately 1:1 to 20:1, for example, as a volume ratio (at 0°C and 1 atm). By setting the flow rate ratio of the inert gas to the cleaning solution within this range, the cleaning efficiency is improved.

[0079] When cleaning the reaction apparatus 100, cleaning may be carried out with cleaning solution flowing through each part, such as the reaction section M. Alternatively, once a certain amount of cleaning has been completed, cleaning may be carried out by allowing the cleaning solution to remain in each part, such as the reaction section M (an example of the third cleaning step). Hereinafter, cleaning in the reaction apparatus 100 by allowing the cleaning solution to remain in each part, such as the reaction section M, may be referred to as "retention cleaning."

[0080] When the object to be cleaned is a soluble substance, once the cleaning of the reactor 100 has progressed to a certain extent, the amount of the object to be cleaned dissolved in the cleaning solution becomes sufficiently small. Therefore, stagnant cleaning can be more economical than cleaning by continuously flowing the cleaning solution, as it can reduce the amount of cleaning solution used.

[0081] When the substance to be cleaned is a soluble substance, and the substance remains in dead spaces inside the reactor 100, for example, in the piping 4 of the reaction section M, such as the joints of the mixing section 41, reactor 42, and pressure relief valve 43 (e.g., ferrule connections), simply continuing to pass the cleaning solution through may not improve the dissolution rate of the substance. In such cases, once the cleaning of the reactor 100 has progressed to a certain extent, allowing the cleaning solution to remain in the reaction section M (piping 4, etc.) and the first line 1 after the pump 11 for a predetermined period to perform retention cleaning, it is possible to effectively clean the dead spaces (dissolve the substance remaining in the dead spaces) with a small amount of cleaning solution.

[0082] The standing time of the cleaning solution during the retention cleaning process described above may be arbitrarily determined depending on the object to be cleaned. One example of such a standing time is between 10 minutes and 24 hours. In order to sufficiently dissolve the object to be cleaned remaining in the dead space, it may be preferable to set the standing time between 12 hours and 24 hours. If the standing time is insufficient, the object to be cleaned will not dissolve completely and will remain in the reaction apparatus 100.

[0083] After performing the stagnant cleaning as described above, it is advisable to perform a final cleaning by replacing the cleaning solution that has been (or has been) stagnant in the reaction section M, etc., with a new cleaning solution (an example of the fourth cleaning step). This final cleaning may be performed by passing the cleaning solution through the reaction section M, etc. This final cleaning allows the cleaning material dissolved in the stagnant cleaning to be discharged out of the system of the reaction apparatus 100 via valves 71 and 78.

[0084] After the final cleaning, inert gas should be supplied to the second line 2 and the cleaning line 3 from valves 74 and 75, and the cleaning liquid remaining in various parts such as the reaction section M should be discharged from the reactor 100 system from valves 78 and 71. Hereinafter, this process of pushing the cleaning liquid out of the reactor 100 system will be referred to as gas purging. Gas purging may be performed by supplying inert gas from only one of valves 74 or 75.

[0085] After gas purging, it is preferable to further dilute any remaining cleaning solution in the reaction section M and other parts with a liquid that does not affect the production of the reaction product (reducing the concentration of the cleaning solution) and discharge it out of the system of the reactor 100 (an example of the fifth cleaning step). This minimizes the amount of cleaning solution remaining in the reactor 100, thereby preventing contamination of the reaction product with components of the cleaning solution during the production of the reaction product after cleaning, and suppressing the resulting deterioration of product quality. Hereinafter, this process of diluting the cleaning solution and discharging it out of the system of the reactor 100 will be referred to as solution purging.

[0086] An example of a solvent used in solution purging is the reaction solvent (solvent component of the first raw material) used in the production of the reaction product. The reaction solvent may be supplied to the reaction section M etc. from the first line 1 by pump 11. Alternatively, the washing liquid in tank 30 may be replaced with the reaction solvent and supplied to the reaction section M etc. from washing line 3 via the first line 1.

[0087] The endpoint of the solution purge may be controlled, for example, by measuring the concentration of the cleaning solution in the solvent discharged from valve 78 and basing the control on this concentration. For example, when this concentration falls below a target value, the solvent purge may be terminated. The termination of the solvent purge completes the stationary cleaning of the reactor 100.

[0088] Further specific examples of the cleaning solution used for stationary cleaning as described above will be explained. The temperature of the cleaning solution may be adjusted as needed. For example, if a higher temperature of the cleaning solution makes cleaning easier by increasing the solubility of the object to be cleaned or by decreasing its adhesion or viscosity, the cleaning solution may be used at a higher temperature. For example, the cleaning solution may be used with the temperature adjusted between 0 and 100°C. When controlling the temperature of the cleaning solution, for example, a temperature control device (e.g., a heating device) may be installed in the tank 30. The temperature of the cleaning solution may also be controlled during the process of passing it through the cleaning line 3.

[0089] If the object to be cleaned is a substance that is solid at room temperature and whose solubility increases as the temperature of the cleaning solution rises, the temperature of the cleaning solution is preferably, for example, 60 to 80°C.

[0090] For example, in a reaction apparatus 100, if we use an ether-based solvent such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, or triethylene glycol dimethyl ether (hereinafter sometimes referred to as the reaction solvent) as the first raw material containing a reducing agent such as NaH or NaBH4, and a second raw material which is a trihalogenated boron gas such as BF3 or BCl3, to produce (generate) diborane as the reaction product, the composition of the washing solution can be any liquid in which salts such as boric acid, sodium tetrahydroborate, or sodium tetrafluoroborate can dissolve. Specific examples of such washing solutions include alcohol solvents such as ethanol, ether solvents such as diethylene glycol dimethyl ether, and water. [Examples]

[0091] The following describes an example in which the reaction apparatus 100 was cleaned in place.

[0092] Diborane was synthesized (produced) using the reaction apparatus 100 described in the above embodiment. After synthesizing a predetermined amount of diborane, by-products (objects to be cleaned) precipitated in the piping 4 and mixing section 41 of the reaction section M of the reaction apparatus 100, causing blockages inside these sections. Therefore, the production of diborane was interrupted, and the reaction apparatus 100 was cleaned in place. The main components of the objects to be cleaned in this embodiment were boric acid, sodium tetrahydroborate, and sodium tetrafluoroborate.

[0093] In this embodiment, the cleaning solution, reaction solvent, cleaning solution delivery conditions (delivery rate, pressure, and temperature), and analytical apparatus used for stationary cleaning were as follows.

[0094] Pure water was used as the washing solution. Diethylene glycol dimethyl ether was used as the reaction solvent for solvent purging. The water concentration in the reaction solvent was 150 ppm.

[0095] The concentration of water in the reaction solvent was measured using the Karl Fischer method (measured using a Karl Fischer moisture meter). The concentration of washing solution (water) in the reaction solvent after solvent purging was also measured using the Karl Fischer method.

[0096] The cleaning solution was delivered at a rate of 100 mL / min, and the supply pressure of the cleaning solution (discharge pressure of pump 31) was set to 0.05 MPa (gauge pressure). The temperature of the cleaning solution was set to 60°C.

[0097] The reaction solvent delivery rate during solvent purging was set to 200 mL / min.

[0098] In this embodiment, stationary cleaning was performed using the following procedure.

[0099] (First washing process) First, valves 74, 77, and 78 were opened, and nitrogen (N2) gas (hereinafter simply referred to as nitrogen) was supplied to the reaction section M as an inert gas. The nitrogen was supplied at a flow rate of 0.9 SLM (Standard Litter Min, per minute when converted to 1 atmosphere at 0°C).

[0100] After supplying nitrogen as described above, valve 72 was opened further, and pump 31 was driven to supply (circulate) the cleaning solution to the reaction section M. The supply of the cleaning solution was continued for 15 minutes.

[0101] (Second washing process) After continuing to supply the cleaning solution in the first cleaning process for 15 minutes, valve 74 was closed to stop the supply of nitrogen. The supply of cleaning solution to reaction section M continued.

[0102] (Third cleaning process) Subsequently, valve 77 was closed, and immediately after the liquid level of the cleaning solution remaining in the recovery container 51 rose to 40% of the capacity of the recovery container 51, pump 31 was stopped to cease the supply of cleaning solution. After that, the system was left to stand for 12 hours with the supply of cleaning solution stopped.

[0103] (Fourth washing process) After stopping the supply of cleaning solution and allowing it to stand for 12 hours, valves 74 and 77 were opened, and pump 31 was driven to supply new cleaning solution, replacing the cleaning solution remaining in reaction section M with the new cleaning solution, and the cleaning solution that had remained in reaction section M was discharged from the system of reactor 100. The supply of cleaning solution to reaction section M continued for 5 minutes.

[0104] (Fifth cleaning process) After continuing to supply the cleaning solution for 5 minutes, gas purging and solvent purging were performed.

[0105] (Gas purging) After continuing to supply the cleaning solution for 5 minutes, pump 31 was stopped. Subsequently, valve 75 was opened to supply nitrogen to cleaning line 3, and the cleaning solution in the first line 1 and the cleaning solution in reaction section M were discharged from the reactor 100 system via valve 78.

[0106] (Solvent purging) After gas purging, valves 77 and 78 were closed, and pump 11 was driven to supply the reaction solvent to the reaction section M. Valves 77 and 78 were opened and closed as needed to allow the reaction solvent to remain for a certain period of time so that the liquid level reached 50% of the capacity of the recovery container 51.

[0107] Then, after the concentration of the washing solution in the reaction solvent discharged through valves 77 and 78 had fallen below a predetermined target value (for example, 160 ppm), pump 11 was stopped to cease the supply of the reaction solvent. Finally, valves 77 and 78 were closed with the reaction solvent remaining in the recovery container 51 to complete the cleaning process.

[0108] In this solvent purging process, the concentration of the washing solution in the reaction solvent discharged through valve 78 immediately after the start of reaction solvent flow exceeded 10,000 ppm. Fifteen minutes after the start of reaction solvent flow, the concentration of the washing solution in the reaction solvent discharged through valve 78 fell below 192 ppm, and after another 30 minutes, it decreased to 147 ppm (equivalent to the concentration of water in the reaction solvent used for solvent purging), which is below the target value (160 ppm), confirming that the cleaning was complete.

[0109] Figure 3 shows a photograph (a photograph of the disassembled joint) illustrating the blockage caused by the cleaning material in the joint section before the stationary cleaning described above (in Figure 3, the joint section between the mixing section 41 and the reactor 42 is shown as an example). Figure 4 shows a photograph (a photograph of the disassembled joint) illustrating the state of the joint section after cleaning. A comparison of Figures 3 and 4 shows that the joint section was properly cleaned by the stationary cleaning method.

[0110] Solid materials tend to accumulate in areas such as where fluid flows or pipelines branch off, inside valve devices, joints, and other areas where fluid flow is obstructed, as well as areas with rough wetted surfaces. In these areas, the flow of the cleaning fluid is also poor, making cleaning difficult and prone to failure with conventional stationary cleaning methods. However, in this embodiment, even in areas that are difficult to clean, such as the joints mentioned above, proper cleaning was achieved while avoiding cleaning failures.

[0111] Furthermore, upon checking the cleaning status of the mixing unit 41 and the recovery device 50, it was found that they had been cleaned appropriately, to the same extent as if they had been disassembled and cleaned.

[0112] Furthermore, when the production of diborane was resumed using the cleaned reactor 100, no problems were observed in the stability of the reactor 100 or in the quality of the diborane as a product gas during the two-week period after cleaning.

[0113] Thus, in this embodiment, by performing stationary cleaning including the first to fifth cleaning steps, the target of cleaning is reliably removed and the residue of cleaning solution is prevented, thereby preventing a deterioration in the quality of the reaction product. Furthermore, since the reaction apparatus 100 can achieve stationary cleaning at a high level that prevents a deterioration in the quality of the reaction product, the method of producing the reaction product using this reaction apparatus 100 is extremely efficient and safe.

[0114] As described above, it is possible to provide a flow-type reactor capable of stationary cleaning, a method for cleaning the flow-type reactor, and a method for producing reaction products.

[0115] [Another embodiment] (1) In the above embodiment, the case in which the cleaning line 3 is connected to the first line 1 was described as shown in Figure 1. However, the cleaning line is not limited to being connected only to the first line 1. Another cleaning line may be provided in addition to cleaning line 3, and this cleaning line may be connected to the second line 2 to perform stationary cleaning of the reaction apparatus 100.

[0116] In this case, the reactor 100 may have both the washing line 3 and another washing line connected to the second line 2, or the reactor 100 may have only the other washing line connected to the second line 2 instead of the washing line 3.

[0117] Furthermore, as described in the above embodiment, when the first raw material is in liquid form and the second raw material is in gaseous form, it is preferable to connect the washing line 3 to the first line 1 through which at least the liquid raw material flows. This is because, when the washing line is connected to the line through which the liquid raw material flows, the washing solution can be diluted with the liquid raw material or its reaction solvent after use.

[0118] (2) In the above embodiment, the case in which the second raw material supplied in the second line 2 is in gaseous form was described as an example, but the second raw material supplied in the second line 2 is not limited to being in gaseous form. The second raw material may be in liquid form, in which case the second line 2 may be configured to have a raw material tank and a liquid transfer pump, for example, like the first line 1.

[0119] (3) In the above embodiment, a gas purging method was described in which, after the final cleaning, an inert gas is supplied from valves 74 and 75 to the second line 2 and the cleaning line 3, and the cleaning liquid remaining in each part such as the reaction section M is discharged from the reactor 100 system through valves 78 and 71. However, gas purging is not limited to this method. For example, after the final cleaning, an inert gas may be supplied from valve 75 to the cleaning line 3, and the cleaning liquid remaining in the first line 1 may be discharged from the reactor 100 system only through valve 71. Alternatively, after the final cleaning, an inert gas may be supplied from valve 74 to the second line 2, and the cleaning liquid remaining in the second line 2 and the reaction section M may be discharged from the reactor 100 system only through valve 77. The inert gas supplied from valves 74 and 75 may be discharged from the reactor 100 system through valve 71, or it may be discharged from the reactor 100 system through valve 78.

[0120] (4) In the above embodiment, it was explained that as a gas purge, after the final cleaning is performed, an inert gas may be supplied from valve 75 to the cleaning line 3 and further discharged from valve 71 to the outside of the reactor 100 system. That is, the case in which an inert gas is supplied from the secondary side of pump 11 to the first line 1 was explained. However, gas purging is not limited to the case in which an inert gas is passed in the direction from valve 75 to valve 71 (in the first line 1, the direction from the secondary side to the primary side). For example, a valve that supplies an inert gas to the first line 1 may be provided between the tank 10 and the pump 11 (i.e., on the primary side of pump 11), and the inert gas may be supplied from this valve to the primary side of pump 11 (filter 12 and reaction section M).

[0121] (5) In the above embodiment, the case in which the reaction unit M has one reactor 42 in the reaction apparatus 100 was described as an example. However, the reaction unit M may have multiple reactors 42 arranged in parallel. The reaction unit M can be easily scaled up by having multiple reactors 42 in parallel.

[0122] Furthermore, the configurations disclosed in the above embodiments (including other embodiments, the same applies hereinafter) can be applied in combination with configurations disclosed in other embodiments, as long as no inconsistencies arise. Moreover, the embodiments disclosed herein are illustrative, and the embodiments of the present invention are not limited thereto, and can be modified as appropriate without departing from the object of the present invention. [Industrial applicability]

[0123] The present invention can be applied to a flow-type reactor, a method for cleaning the flow-type reactor, and a method for producing reaction products. [Explanation of symbols]

[0124] 1: First Line 10: Tank (raw material tank) 100: Reactor (flow reactor) 11: Pump (liquid transfer pump) 12: Filter 13:Flow meter 17: Confluence 1a:Horizontal piping section 2: Second line 20: Cylinder 21: Pressure regulating valve 23:Flowmeter 3: Washing Line 30: Tank (washing tank) 31: Pump (washing pump) 3a: Downward piping section 4: Piping 41: Mixing section 42: Reactor (tubular reactor) 43: Pressure relief valve 50: Recovery device (separation and recovery device) 51: Collection container 52: Level Sensor 53: Pressure reducing pump 5a: Piping 5b: Piping 71: Valve 72: Valve 73: Valve 74: Valve 75: Valve 76: Valve 77: Valve 78: Valve 79: Valve G1: Direction G2 :Direction M: Reaction section

Claims

1. A mixing section is provided for mixing a liquid first raw material fluid with a gaseous second raw material fluid, and a reaction section is provided for continuously generating reaction products by continuously chemically reacting the first raw material and the second raw material, A first line is a pipe that supplies the first raw material to the reaction section, A second line is a pipe that supplies the second raw material to the reaction section, The system includes a cleaning line which is a pipe that supplies cleaning liquid to the reaction section, The cleaning line is a cleaning method for a flow-type reactor connected to the first line, A first cleaning step involves supplying a cleaning solution and an inert gas to the reaction section, A second cleaning step is performed after the first cleaning step, in which only cleaning solution is supplied to the reaction section. A third cleaning step is performed after the second cleaning step, in which the cleaning solution is retained in the reaction section. A fourth cleaning step is performed after the third cleaning step, in which the cleaning solution remaining in the reaction section is replaced with a new cleaning solution. The process includes a fifth cleaning step, which is performed after the fourth cleaning step, to reduce the concentration of the cleaning solution remaining in the reaction section, A method for cleaning a flow-type reactor, wherein in the first cleaning step, the cleaning liquid is supplied via the first line and the inert gas is supplied via the second line, thereby simultaneously supplying the cleaning liquid and the inert gas, and the cleaning liquid and the inert gas are passed through the reaction section in a gas-liquid multiphase flow state.

2. The first line further comprises a filter, The washing line is connected between the filter and the mixing unit in the first line. The method for cleaning a flow-type reactor according to claim 1, wherein the first cleaning step further involves back-washing the filter with the cleaning solution.

3. The first raw material includes the reaction solvent in the chemical reaction, A method for cleaning a flow-type reactor according to claim 1 or 2, wherein in the fifth cleaning step, an inert gas is supplied to the reaction section to push the cleaning liquid out of the system, and then the reaction solvent is supplied to the reaction section to push the cleaning liquid out of the system and reduce the concentration of the cleaning liquid.

4. The first raw material is the reaction solvent, and NaH and NaBH ４ Including at least one of the following, The second raw material is boron trihalide gas. The aforementioned cleaning solution contains water, The method for cleaning a flow-type reaction apparatus according to claim 3, wherein the reaction product is diborane.

5. A mixing section is provided for mixing the fluid of a first raw material and the fluid of a second raw material, and a reaction section is provided for continuously generating reaction products by continuously chemically reacting the first raw material and the second raw material, A first line is a pipe that supplies the first raw material to the reaction section, A second line is a pipe that supplies the second raw material to the reaction section, The system includes a cleaning line which is a pipe that supplies cleaning liquid to the reaction section, The washing line is a method for producing a reaction product using a flow-type reactor connected to the first line, A reaction step in which a first raw material and a second raw material are continuously chemically reacted using the flow-type reactor to continuously produce reaction products, This includes a settling cleaning step for the flow-type reactor, The aforementioned stationary washing process is: A first cleaning step involves supplying a cleaning solution and an inert gas to the reaction section, A second cleaning step is performed after the first cleaning step, in which only cleaning solution is supplied to the reaction section. A third cleaning step is performed after the second cleaning step, in which the cleaning solution is retained in the reaction section. A fourth cleaning step is performed after the third cleaning step, in which the cleaning solution remaining in the reaction section is replaced with a new cleaning solution. The process includes a fifth cleaning step, which is performed after the fourth cleaning step, to reduce the concentration of the cleaning solution remaining in the reaction section, A method for producing a reaction product, wherein in the first washing step, the washing liquid is supplied via the first line and the inert gas is supplied via the second line, thereby simultaneously supplying the washing liquid and the inert gas, and the washing liquid and the inert gas are passed through the reaction section in a gas-liquid multiphase flow state.

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