A fluidized reaction device and method for producing chlorothalonil therefor

Abstract

The present invention provides a fluidized reaction device and a method for producing chlorothalonil therefor. The fluidized reaction device comprises a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independently arranged in sequence from top to bottom in a reactor body; the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are independently (0.05-0.2):1, and the reaction temperatures at different axial heights of the reactor body can be well controlled, so that the temperature distribution inside the reactor body is uniform without local overheating areas, and the catalyst is ensured not to coke in the reactor body; the method for producing chlorothalonil with the fluidized reaction device can extend the service life of a single batch of catalysts and increase the proportion of chlorothalonil in hexachlorobenzene below 10 ppm in the product.

Description

Technical Field

[0001] The present invention relates to the technical field of fluidized bed reaction devices, and in particular to a fluidized bed reaction device and a method for producing thiophanate-methyl using the fluidized bed reaction device. Background Art

[0002] Chlorothalonil is a highly effective, low-toxic, low-residue protective fungicide, which is widely used in the prevention and control of fungal diseases in agriculture and forestry, especially in cash crops such as vegetables and fruits, and can prevent and control 52 diseases of more than 30 crops. In addition, chlorothalonil also has important uses in the field of mildew prevention, such as the manufacture of mildew-proof coatings and mildew-proof wallpapers. The production scale of chlorothalonil in China is constantly expanding, and it has become one of the world's large-tonnage excellent pesticide varieties.

[0003] Fluidized bed is the most critical equipment in the production of chlorothalonil, which is directly related to the output and product quality of chlorothalonil. The reaction of synthesizing chlorothalonil in the fluidized bed is an exothermic reaction. How to quickly and stably remove the heat and ensure that there is no local overheating area in the bed is a problem that the heat exchange tube needs to solve.

[0004] CN101985089B discloses a shell-and-tube fluidized bed reactor for the production of thiophanate-methyl. The fluidized bed of the reactor includes a serpentine tube heat exchanger and a shell-and-tube heat exchanger. The serpentine tube heat exchanger is arranged below the lower head of the fluidized bed, and the shell-and-tube heat exchanger is arranged between the serpentine tube heat exchanger and the fluidized bed cylinder, but only contains a section of heat exchange tubes, which is prone to local overheating areas.

[0005] CN100404500C discloses a method for producing chlorothalonil with low hexachlorobenzene content, in which isophthalonitrile is completely vaporized and taken out of the vaporizer with nitrogen, and then mixed with chlorine and enters a fluidized bed for the first step of reaction. The reaction product is mixed with chlorine again and enters a fixed bed for chlorination. The output mixed gas is condensed and collected to obtain a chlorothalonil product, but the removal of heat in the fluidized bed is not involved.

[0006] CN201825895U discloses a novel chlorothalonil production device, which includes a nitrogen generator, a vaporizer, a mixer, a fixed bed, a fluidized bed, a receiver, and a dryer; a pipeline is provided from the nitrogen generator to the vaporizer, a pipeline is provided from the vaporizer to the mixer, a pipeline is provided from the mixer to the fixed bed, a pipeline is provided from the fixed bed to the fluidized bed, a pipeline is provided from the fluidized bed to the receiver, and a first conveyor is provided from the receiver to the dryer, but does not involve the removal of heat in the fluidized bed.

[0007] Therefore, it is necessary to develop a fluidized reaction device that can quickly remove the reaction heat and make the temperature inside the reactor body uniform, which has broad application prospects. Summary of the invention

[0008] In view of the problems existing in the prior art, the present invention provides a fluidized reaction device, which includes a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independently arranged from top to bottom in a reactor body; the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are independently (0.05-0.2):1; the reaction temperatures at different axial heights of the reactor body can be well controlled, so that the temperature distribution inside the reactor body is uniform without local overheating areas, thereby ensuring that the catalyst does not coke in the fluidized reaction device; the method for using the fluidized reaction device to produce chlorothalonil can extend the service life of a single batch of catalysts and increase the proportion of chlorothalonil in hexachlorobenzene below 10 ppm in the product.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a fluidized reaction device, comprising a reactor body; the reactor body comprises, from top to bottom, a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independent of each other; the ratio of the height of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body is independently (0.05-0.2):1, for example, it can be 0.05:1, 0.08:1, 0.1:1, 0.12:1, 0.14:1, 0.16:1, 0.18:1 or 0.2:1, etc.

[0011] The fluidized reaction device in the present invention includes a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independently arranged from top to bottom in the reactor body. Heat exchange media of different temperatures are introduced into the three heat exchange tube groups, so that the reaction temperature of the fluidized reaction device at different axial heights can be well controlled, so that the internal temperature distribution is uniform, there is no local overheating area, and the catalyst is ensured not to coke in the fluidized reaction device; the ratio of the height of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body is independently (0.05-0.2):1, which can well ensure the accuracy of the reaction temperature gradient of the fluidized bed in the axial direction, ensure that the heights of the concentrated phase section and the dilute phase section of the reaction are reasonable, and can increase the reaction yield and improve the content of thiophanate-methyl in the product.

[0012] Preferably, the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all U-shaped heat exchange tubes having only a single inlet and outlet.

[0013] In the present invention, the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are U-shaped heat exchange tubes having only a single inlet and outlet, which can fully overcome the influence of thermal expansion and contraction and prevent the heat exchange tubes from rupturing.

[0014] Preferably, the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all arranged in a regular octagon on the radial cross section of the fluidized reaction device.

[0015] In the present invention, the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all arranged in a regular octagon on the radial cross-section of the fluidized reaction device, which can ensure sufficient radial heat exchange of the fluidized reaction device without dead heat exchange zones, so that the temperature distribution inside the fluidized reaction device is uniform without local overheating areas.

[0016] Preferably, the materials of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group independently include carbon steel, Hastelloy, stainless steel 304, stainless steel 316 or stainless steel 316L, preferably stainless steel 316.

[0017] Preferably, the nominal diameters of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are each independently 20-100 mm, for example, 20 mm, 25 mm, 30 mm, 40 mm, 45 mm, 50 mm, 60 mm, 65 mm, 70 mm, 80 mm, 90 mm or 100 mm, etc., preferably 50-80 mm.

[0018] Preferably, the ratio of the height of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body is independently (0.1-0.15):1, for example, it can be 0.1:1, 0.11:1, 0.12:1, 0.13:1, 0.14:1 or 0.15:1, etc.

[0019] In the present invention, the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are independently (0.1-0.15):1, which can well ensure the accuracy of the reaction temperature gradient of the fluidized bed in the axial direction, ensure that the heights of the concentrated phase section and the dilute phase section of the reaction are reasonable, increase the reaction yield, and improve the content of thiophanate-methyl in the product.

[0020] Preferably, the distance between the axial centers of each heat exchange tube of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group on the radial cross-section of the fluidized reaction device is independently 100-500 mm, for example, it can be 100 mm, 150 mm, 200 mm, 250 mm, 300 mm, 350 mm, 400 mm, 450 mm or 500 mm, etc., preferably 200-300 mm.

[0021] Preferably, the fluidized reactor further comprises a catalyst outlet.

[0022] Preferably, the catalyst outlet is arranged at the bottom of the reactor body.

[0023] Preferably, an air intake passage is provided between the third heat exchange tube group and the catalyst outlet.

[0024] Preferably, the outlet of the intake passage faces the catalyst inlet.

[0025] Preferably, the fluidized bed reactor further comprises an air inlet connected to the air inlet channel.

[0026] Preferably, the gas inlet is arranged on one side of the lower part of the reactor body.

[0027] Preferably, the fluidized reaction device further comprises a gas outlet.

[0028] Preferably, the gas outlet is arranged on one side of the upper part of the reactor body.

[0029] Preferably, the gas outlet is arranged at the upper part of the first heat exchange tube group.

[0030] Preferably, the fluidized reactor further comprises a catalyst inlet.

[0031] Preferably, the catalyst inlet is arranged at the top of the reactor body.

[0032] In a second aspect, the present invention provides a method for producing thiophanate-methyl, wherein the method is carried out using the fluidized reaction apparatus described in the first aspect.

[0033] Preferably, the method comprises the following steps:

[0034] (1) respectively introducing heat exchange media of different temperatures into the first heat exchange tube group, the second heat exchange tube group, and the third heat exchange tube group;

[0035] (2) The raw materials come into contact with the catalyst in the reactor body and react.

[0036] Heat exchange media of different temperatures are introduced into the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group in the fluidized reaction device. The raw materials contact the catalyst in the reactor body and react. The reaction is an exothermic reaction. The degree of reaction at different axial heights of the fluidized reaction device is different, and the reaction heat at different axial heights of the fluidized reaction device is different. The introduction of heat exchange media of different temperatures into the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group can well control the reaction temperature at different axial heights of the fluidized bed, thereby ensuring that the catalyst does not coke in the fluidized bed.

[0037] Preferably, the heat exchange medium in step (1) includes heat transfer oil and / or molten salt.

[0038] Preferably, the temperature of the heat exchange medium in the first heat exchange tube group is 310-340°C, for example, it can be 310°C, 313°C, 316°C, 319°C, 322°C, 325°C, 328°C, 331°C, 334°C, 337°C or 340°C, etc., preferably 320-330°C.

[0039] Preferably, the temperature of the heat exchange medium in the second heat exchange tube group is 270-300°C, for example, it can be 270°C, 273°C, 276°C, 279°C, 282°C, 285°C, 288°C, 291°C, 294°C, 297°C or 300°C, etc., preferably 280-290°C.

[0040] Preferably, the temperature of the heat exchange medium in the third heat exchange tube group is 240-270°C, for example, it can be 240°C, 243°C, 246°C, 249°C, 252°C, 255°C, 258°C, 261°C, 264°C, 267°C or 270°C, etc., preferably 250-260°C.

[0041] Preferably, the raw materials in step (2) include isophthalonitrile, chlorine and nitrogen.

[0042] Isophthalonitrile reacts with chlorine to produce tetrachloroisophthalonitrile, i.e., thiophanate-methyl. Nitrogen is used as a diluent gas to vaporize or atomize isophthalonitrile and adjust the concentration of reactants.

[0043] Preferably, the volume concentration of isophthalonitrile is 5-7%, for example, it can be 5%, 5.2%, 5.4%, 5.6%, 5.8%, 6.0%, 6.2%, 6.4%, 6.6%, 6.8% or 7.0%.

[0044] Preferably, the volume concentration of the chlorine gas is 25-45%, for example, it can be 25%, 28%, 31%, 34%, 37%, 40%, 43% or 45%.

[0045] Preferably, the volume concentration of the nitrogen is 48-70%, for example, 48%, 50%, 53%, 56%, 59%, 62%, 65%, 68% or 70%.

[0046] Preferably, the mass space velocity of isophthalonitrile is 0.05 to 0.1 h -1 , for example, it can be 0.05h -1 、0.06h -1 、0.07h -1 、0.08h -1 、0.09h -1 or 0.10h -1 wait.

[0047] Preferably, the catalyst comprises coconut shell activated carbon.

[0048] Preferably, the temperature in the first heat exchange tube group area in the reactor body is controlled to be 320-330°C, for example, it can be 320°C, 321°C, 322°C, 323°C, 324°C, 325°C, 326°C, 327°C, 328°C, 329°C or 330°C, etc.

[0049] Preferably, the temperature in the second heat exchange tube group area in the reactor body is controlled to be 280-290°C, for example, it can be 280°C, 281°C, 282°C, 283°C, 284°C, 285°C, 286°C, 287°C, 288°C, 289°C or 290°C.

[0050] Preferably, the temperature in the third heat exchange tube group area in the reactor body is controlled to be 250-260°C, for example, it can be 250°C, 251°C, 252°C, 253°C, 254°C, 255°C, 256°C, 257°C, 258°C, 259°C or 260°C.

[0051] The method for producing chlorothalonil in the fluidized reaction device of the first aspect of the present invention comprises the following steps:

[0052] (1) A heat exchange medium at 310-340° C. is introduced into the first heat exchange tube group, a heat exchange medium at 270-300° C. is introduced into the second heat exchange tube group, and a heat exchange medium at 240-270° C. is introduced into the third heat exchange tube group;

[0053] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 5-7%, the volume concentration of chlorine is 25-45%, the volume concentration of nitrogen is 48-70%, and the mass space velocity of isophthalonitrile is 0.05-0.1h -1 , the mixed gas contacts with the catalyst to react;

[0054] (3) In the reactor body, the temperature in the first heat exchange tube group area is controlled to be 320-330°C, the temperature in the second heat exchange tube group area is controlled to be 280-290°C, and the temperature in the third heat exchange tube group area is controlled to be 250-260°C.

[0055] Compared with the prior art, the present invention has at least the following beneficial effects:

[0056] (1) The fluidized bed reactor and the method for producing chlorothalonil provided by the present invention can well control the reaction temperature at different axial heights of the fluidized bed by providing three independent heat exchange tube groups, into which heat exchange media of different temperatures are introduced respectively, thereby ensuring that the catalyst does not coke in the fluidized bed;

[0057] (2) In the fluidized bed reactor and the method for producing chlorothalonil provided by the present invention, the three-stage heat exchange tube group adopts a regular octagonal arrangement in the radial cross section of the fluidized bed reactor, so that the heat exchange in the radial direction of the fluidized bed reactor is sufficient, there is no heat exchange dead zone, the temperature distribution inside the fluidized bed reactor is uniform, and there is no local overheating area;

[0058] (3) In the fluidized bed reactor and the method for producing chlorothalonil provided by the present invention, the three-stage heat exchange tube groups are all U-shaped heat exchange tubes with only a single inlet and outlet, which can fully overcome the influence of thermal expansion and contraction and prevent the heat exchange tube from rupturing;

[0059] (4) The fluidized bed reactor and the method for producing chlorothalonil provided by the present invention can extend the service life of a single batch of catalyst to more than 11 days and increase the proportion of chlorothalonil in the product with hexachlorobenzene less than 10 ppm to more than 20 wt%. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a schematic structural diagram of the fluidized bed reaction device in Example 1 of the present invention.

[0061] Figure 2 It is a top view of the layout of the heat exchange tube group in Example 1 of the present invention.

[0062] In the figure: 1-catalyst outlet; 2-air inlet channel; 3-third heat exchange tube group; 4-second heat exchange tube group; 5-first heat exchange tube group; 6-gas outlet; 7-catalyst inlet. DETAILED DESCRIPTION

[0063] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0064] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0065] 1. Implementation

[0066] The present invention provides a fluidized bed reaction device, which includes a reactor body, which includes a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independent of each other from top to bottom, all of which are U-shaped heat exchange tubes with only a single inlet and outlet, and are arranged in a regular octagon; a catalyst outlet is arranged at the bottom of the reactor body, an air inlet channel is arranged between the third heat exchange tube group and the catalyst outlet, the outlet of the air inlet channel faces the catalyst outlet, the air inlet connected to the air inlet channel is arranged on one side of the lower part of the reactor body, the gas outlet is arranged on one side of the upper part of the reactor body, and is arranged on the upper part of the first heat exchange tube group, and the catalyst inlet is arranged on the top of the reactor body.

[0067] The ratio of the height of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body is independently (0.05-0.2):1, the material independently includes carbon steel, Hastelloy, stainless steel 304, stainless steel 316 or stainless steel 316L, the nominal diameter is independently 20-100 mm, and the distance between the axes of each heat exchange tube on the radial section of the fluidized reaction device is independently 100-500 mm.

[0068] Example 1

[0069] This embodiment provides a fluidized reaction device, such as Figure 1 As shown, the fluidized bed reaction device includes a reactor body, which includes a first heat exchange tube group 5, a second heat exchange tube group 4 and a third heat exchange tube group 3 which are independent of each other from top to bottom, all of which are U-shaped heat exchange tubes with only a single inlet and outlet, and are arranged in a regular octagon, as shown in FIG. Figure 2 As shown; the catalyst outlet 1 is arranged at the bottom of the reactor body, an air inlet channel 2 is arranged between the third heat exchange tube group 3 and the catalyst outlet 1, the outlet of the air inlet channel 2 faces the catalyst outlet 1, the air inlet connected to the air inlet channel 2 is arranged on the lower side of the reactor body, the gas outlet 6 is arranged on the upper side of the reactor body, and is arranged on the upper part of the first heat exchange tube group 5, and the catalyst inlet 7 is arranged at the top of the reactor body.

[0070] The ratios of the height of the first heat exchange tube group 5, the second heat exchange tube group 4 and the third heat exchange tube group 3 to the height of the reactor body are 0.125, 0.125 and 0.1 respectively. They are all made of stainless steel 316, with a nominal diameter of 50 mm. The distance between the axes of the heat exchange tubes on the radial section of the fluidized reaction device is 200 mm.

[0071] Example 2

[0072] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and Embodiment 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.125, 0.125 and 0.15 respectively, and the rest are the same as Embodiment 1.

[0073] Example 3

[0074] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and Embodiment 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.15, 0.15 and 0.1 respectively, and the rest are the same as Embodiment 1.

[0075] Example 4

[0076] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and Example 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.15, 0.2 and 0.05 respectively, and the rest are the same as Example 1.

[0077] Example 5

[0078] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and Embodiment 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.2, 0.1 and 0.1 respectively, and the rest are the same as Embodiment 1.

[0079] Example 6

[0080] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and Example 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.05, 0.05 and 0.2 respectively, and the rest are the same as Example 1.

[0081] Example 7

[0082] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and Example 1 is that the nominal diameters of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all 80 mm and the distance between the axes of each heat exchange tube on the radial section of the fluidized bed reaction device is 300 mm. The rest is the same as Example 1.

[0083] Example 8

[0084] This embodiment provides a fluidized bed reaction device. The difference between the fluidized bed reaction device and the embodiment 1 is that the material is stainless steel 316L, the nominal diameter is 20 mm, the distance between the axes of the heat exchange tubes on the radial section of the fluidized bed reaction device is 100 mm, and the rest is the same as the embodiment 1.

[0085] Example 9

[0086] This embodiment provides a fluidized bed reaction device. The difference between the fluidized bed reaction device and the embodiment 1 is that the material is stainless steel 316L, the nominal diameter is 100 mm, the distance between the axes of the heat exchange tubes on the radial section of the fluidized bed reaction device is 500 mm, and the rest is the same as the embodiment 1.

[0087] Example 10

[0088] This embodiment provides a fluidized bed reaction device, and the difference between the fluidized bed reaction device and the embodiment 1 is that the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all arranged in a regular quadrilateral on the radial cross section of the fluidized bed reaction device, and the rest is the same as the embodiment 1.

[0089] 2. Comparison

[0090] Comparative Example 1

[0091] This comparative example provides a fluidized bed reaction device, which is different from Example 1 only in that the third heat exchange tube group is not provided in the reactor body, and the rest is the same as Example 1.

[0092] Comparative Example 2

[0093] This comparative example provides a fluidized bed reaction device, which is different from Example 1 only in that the second heat exchange tube group and the third heat exchange tube group are not provided in the reactor body, and the rest are the same as Example 1.

[0094] Comparative Example 3

[0095] This comparative example provides a fluidized bed reaction device, the difference between the fluidized bed reaction device and Example 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.03, 0.03 and 0.02 respectively, and the rest are the same as Example 1.

[0096] Comparative Example 4

[0097] This comparative example provides a fluidized bed reaction device, the difference between the fluidized bed reaction device and Example 1 is that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.3, 0.25 and 0.25 respectively, and the rest are the same as Example 1.

[0098] 3. Application Examples

[0099] Application Example 1

[0100] This application example provides a method for producing thiophanate-methyl, which is carried out in the fluidized reaction device provided in Example 1, and comprises the following steps:

[0101] (1) A heat transfer oil at 320°C is introduced into the first heat exchange tube group, a heat transfer oil at 290°C is introduced into the second heat exchange tube group, and a heat transfer oil at 250°C is introduced into the third heat exchange tube group;

[0102] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 5%, the volume concentration of chlorine is 25%, the volume concentration of nitrogen is 70%, and the mass space velocity of isophthalonitrile is 0.1 h-1 , the mixed gas contacts with the catalyst to react;

[0103] (3) In the reactor body, the temperature in the first heat exchange tube group area is controlled to be 320°C, the temperature in the second heat exchange tube group area is controlled to be 290°C, and the temperature in the third heat exchange tube group area is controlled to be 250°C.

[0104] Application Example 2

[0105] This application example provides a method for producing thiophanate-methyl, which is carried out in the fluidized bed reactor provided in Example 2, and comprises the following steps:

[0106] (1) 320° C. molten salt is introduced into the first heat exchange tube group, 290° C. molten salt is introduced into the second heat exchange tube group, and 260° C. molten salt is introduced into the third heat exchange tube group;

[0107] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 7%, the volume concentration of chlorine is 35%, the volume concentration of nitrogen is 58%, and the mass space velocity of isophthalonitrile is 0.05 h -1 , the mixed gas contacts with the catalyst to react;

[0108] (3) In the reactor body, the temperature in the first heat exchange tube group area was controlled to be 325°C, the temperature in the second heat exchange tube group area was controlled to be 290°C, and the temperature in the third heat exchange tube group area was controlled to be 260°C.

[0109] Application Example 3

[0110] This application example provides a method for producing thiophanate-methyl, which is carried out in the fluidized reaction device provided in Example 3, and comprises the following steps:

[0111] (1) introducing 330°C heat transfer oil into the first heat exchange tube group, introducing 280°C heat transfer oil into the second heat exchange tube group, and introducing 250°C heat transfer oil into the third heat exchange tube group;

[0112] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 7%, the volume concentration of chlorine is 45%, the volume concentration of nitrogen is 48%, and the mass space velocity of isophthalonitrile is 0.75 h -1 , the mixed gas contacts with the catalyst to react;

[0113] (3) In the reactor body, the temperature in the first heat exchange tube group area was controlled to be 330°C, the temperature in the second heat exchange tube group area was controlled to be 280°C, and the temperature in the third heat exchange tube group area was controlled to be 255°C.

[0114] Application Example 4

[0115] This application example provides a method for producing thiophanate-methyl, which is carried out in the fluidized bed reactor provided in Example 4, and comprises the following steps:

[0116] (1) introducing heat transfer oil at 310°C into the first heat exchange tube group, introducing heat transfer oil at 280°C into the second heat exchange tube group, and introducing heat transfer oil at 240°C into the third heat exchange tube group;

[0117] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 6%, the volume concentration of chlorine is 25%, the volume concentration of nitrogen is 69%, and the mass space velocity of isophthalonitrile is 0.06h -1 , the mixed gas contacts with the catalyst to react;

[0118] (3) In the reactor body, the temperature in the first heat exchange tube group area is controlled to be 320°C, the temperature in the second heat exchange tube group area is controlled to be 285°C, and the temperature in the third heat exchange tube group area is controlled to be 250°C.

[0119] Application Example 5

[0120] This application example provides a method for producing thiophanate-methyl, which is carried out in the fluidized reaction device provided in Example 5, and comprises the following steps:

[0121] (1) A heat transfer oil at 330°C is introduced into the first heat exchange tube group, a heat transfer oil at 270°C is introduced into the second heat exchange tube group, and a heat transfer oil at 240°C is introduced into the third heat exchange tube group;

[0122] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 6%, the volume concentration of chlorine is 30%, the volume concentration of nitrogen is 64%, and the mass space velocity of isophthalonitrile is 0.08 h -1 , the mixed gas contacts with the catalyst to react;

[0123] (3) In the reactor body, the temperature in the first heat exchange tube group area is controlled to be 330°C, the temperature in the second heat exchange tube group area is controlled to be 280°C, and the temperature in the third heat exchange tube group area is controlled to be 250°C.

[0124] Application Example 6

[0125] This application example provides a method for producing thiophanate-methyl, which is carried out in the fluidized reaction device provided in Example 6, and comprises the following steps:

[0126] (1) A heat transfer oil at 310°C is introduced into the first heat exchange tube group, a heat transfer oil at 270°C is introduced into the second heat exchange tube group, and a heat transfer oil at 250°C is introduced into the third heat exchange tube group;

[0127] (2) A mixed gas of isophthalonitrile, chlorine and nitrogen is introduced into the reactor body, wherein the volume concentration of isophthalonitrile is 6%, the volume concentration of chlorine is 30%, the volume concentration of nitrogen is 64%, and the mass space velocity of isophthalonitrile is 0.09 h -1 ,, the mixed gas contacts with a catalyst to react;

[0128] (3) In the reactor body, the temperature in the first heat exchange tube group area was controlled to be 320°C, the temperature in the second heat exchange tube group area was controlled to be 280°C, and the temperature in the third heat exchange tube group area was controlled to be 255°C.

[0129] Application Example 7

[0130] This application example provides a method for producing thiophanate-methyl. The method is different from that in application example 1 only in that it is carried out in the fluidized bed reactor provided in Example 7, and the rest is the same as in application example 1.

[0131] Application Example 8

[0132] This application example provides a method for producing thiophanate-methyl. The method is different from that in application example 1 only in that it is carried out in the fluidized bed reactor provided in Example 8, and the rest is the same as in application example 1.

[0133] Application Example 9

[0134] This application example provides a method for producing thiophanate-methyl. The method is different from that in application example 1 only in that it is carried out in the fluidized bed reactor provided in Example 9, and the rest is the same as in application example 1.

[0135] Application Example 10

[0136] This application example provides a method for producing thiophanate-methyl. The method is different from that in application example 1 only in that it is carried out in the fluidized bed reactor provided in Example 10, and the rest is the same as in application example 1.

[0137] 4. Application comparison

[0138] Application Comparative Example 1

[0139] This comparative example provides a method for producing thiophanate-methyl. The method is different from that in Application Example 1 only in that it is carried out in the fluidized reaction device provided in Comparative Example 1, and the rest is the same as that in Application Example 1.

[0140] Application Comparative Example 2

[0141] This comparative example provides a method for producing thiophanate-methyl. The method is different from that in Application Example 1 only in that it is carried out in the fluidized reaction device provided in Comparative Example 2, and the rest is the same as in Application Example 1.

[0142] Application Comparative Example 3

[0143] This comparative example provides a method for producing thiophanate-methyl. The method is different from that in Application Example 1 only in that it is carried out in the fluidized reaction device provided in Comparative Example 3, and the rest is the same as that in Application Example 1.

[0144] Application Comparative Example 4

[0145] This comparative example provides a method for producing thiophanate-methyl. The method is different from that in Application Example 1 only in that it is carried out in the fluidized reaction device provided in Comparative Example 4, and the rest is the same as that in Application Example 1.

[0146] V. Test and Results

[0147] The reaction product at the gas outlet of the fluidized bed reactor enters the collector for cooling, and the product and impurities in the reaction product are cooled and condensed into a solid powdery chlorothalonil product in six collectors connected in series. The solid powdery chlorothalonil product in the collector falls into the packaging bag at the bottom of the collector by its own gravity. The main impurities in the chlorothalonil product are pentachlorobenzonitrile and hexachlorobenzene.

[0148] Test method for the proportion of chlorothalonil containing hexachlorobenzene below 10 ppm in products: Weigh and test the content of the products collected in each trap respectively, so as to obtain the proportion of chlorothalonil containing hexachlorobenzene below 10 ppm in all products.

[0149] The test results of the above application examples and application comparison examples are shown in Table 1.

[0150] Table 1

[0151]

[0152]

[0153] From Table 1, we can see the following points:

[0154] (1) The present invention provides a fluidized bed reactor, comprising a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independently arranged in sequence from top to bottom in a reactor body; the ratio of the height of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body is independently (0.05-0.2):1; the method for producing chlorothalonil using the fluidized bed reactor can well control the reaction temperature at different axial heights of the reactor body, so that the temperature distribution inside the reactor body is uniform without local overheating areas, ensuring that the catalyst does not coke in the fluidized bed reactor, and can extend the service life of a single batch of catalysts, and increase the proportion of chlorothalonil in hexachlorobenzene below 10 ppm in the product. Specifically, the service life of a single batch of catalysts in Application Examples 1-10 is ≥11 days, and the proportion of chlorothalonil in hexachlorobenzene below 10 ppm in the product is ≥20 wt%;

[0155] (2) In combination with Application Example 1 and Application Example 10, it can be seen that the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group in Application Example 1 are all arranged in a regular octagon on the radial cross section of the fluidized reactor. Compared with the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group in Application Example 10, which are all arranged in a regular quadrilateral on the radial cross section of the fluidized reactor, the use time of a single batch of catalyst in Application Example 1 is 16 days, and the proportion of thiophanate-methyl in the product with hexachlorobenzene below 10 ppm is 29 wt%, while the use time of a single batch of catalyst in Application Example 10 is 11 days, and the proportion of thiophanate-methyl in the product with hexachlorobenzene below 10 ppm is 22 wt%. This shows that the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group in the present invention are all arranged in a regular octagon on the radial cross section of the fluidized reactor, which can extend the use time of a single batch of catalyst and increase the proportion of thiophanate-methyl in the product with hexachlorobenzene below 10 ppm;

[0156] (3) In combination with Application Example 1 and Application Comparative Examples 1-2, it can be seen that Application Example 1 is provided with a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group. Compared with Application Comparative Example 1 in which the third heat exchange tube group is not provided and Application Comparative Example 2 in which the second heat exchange tube group and the third heat exchange tube group are not provided, the use time of a single batch of catalyst in Application Example 1 is 16 days, and the proportion of thiophanate-methyl in the product with hexachlorobenzene below 10 ppm is 29 wt %, while the use time of a single batch of catalyst in Application Comparative Examples 1-2 is 11 days and 10 days, respectively, and the proportion of thiophanate-methyl in the product with hexachlorobenzene below 10 ppm is 13 wt % and 11 wt %, respectively. This indicates that the provision of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group in the present invention can extend the use time of a single batch of catalyst and increase the proportion of thiophanate-methyl in the product with hexachlorobenzene below 10 ppm;

[0157] (4) Combining Application Example 1 and Application Comparative Examples 3 to 4, it can be seen that in Application Example 1, the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.125, 0.125 and 0.1, respectively. Compared with Application Comparative Example 3, the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.03, 0.03 and 0.02, respectively. In Application Comparative Example 4, the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are 0.3, 0.25 and 0.25, respectively. For example, the service life of a single batch of catalyst in Application Example 1 is 16 days, and the proportion of thiophanate-methyl in hexachlorobenzene below 10 ppm in the product is 29 wt %, while the service life of a single batch of catalyst in Comparative Examples 3 to 4 is 10 days and 9 days, respectively, and the proportion of thiophanate-methyl in hexachlorobenzene below 10 ppm in the product is 8 wt %. This indicates that the ratios of the heights of the first heat exchange tube group, the second heat exchange tube group, and the third heat exchange tube group to the reactor body in the present invention are respectively controlled within a certain range, which can extend the service life of a single batch of catalyst and increase the proportion of thiophanate-methyl in hexachlorobenzene below 10 ppm in the product.

[0158] In summary, the present invention provides a fluidized bed device, which has a simple structure and is used in the method for producing chlorothalonil. The reaction temperature at different axial heights of the reactor body can be well controlled, so that the temperature distribution inside the reactor body is uniform, there is no local overheating area, and the catalyst is ensured not to coke in the fluidized bed device. The service life of a single batch of catalysts can be extended to more than 11 days, and the proportion of chlorothalonil in hexachlorobenzene below 10 ppm in the product is increased to more than 20wt%.

[0159] The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed structural features, that is, it does not mean that the present invention must rely on the above-mentioned detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A fluidized bed reactor, characterized in that: The fluidized reaction device comprises a reactor body; The reactor body includes, from top to bottom, a first heat exchange tube group, a second heat exchange tube group and a third heat exchange tube group which are independent of each other; The ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are independently (0.05-0.2):1; The first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all arranged in a regular octagon in the radial cross section of the fluidized reaction device; The nominal diameters of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are each independently 20-100 mm.

2. The fluidized bed reactor according to claim 1, characterized in that: The first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are all U-shaped heat exchange tubes having only a single inlet and outlet.

3. The fluidized bed reactor according to claim 1, characterized in that: The materials of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group independently include carbon steel, Hastelloy, stainless steel 304, stainless steel 316 or stainless steel 316L.

4. The fluidized bed reactor according to claim 3, characterized in that: The materials of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are independently made of stainless steel 316.

5. The fluidized bed reactor according to claim 1, characterized in that: The nominal diameters of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group are each independently 50-80 mm.

6. The fluidized bed reactor according to claim 1, characterized in that: The ratios of the heights of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group to the height of the reactor body are each independently (0.1-0.15):

1.

7. The fluidized bed reactor according to claim 1, characterized in that: The distances between the axial centers of the heat exchange tubes of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group on the radial cross section of the fluidized reaction device are independently 100-500 mm.

8. The fluidized bed reactor according to claim 7, characterized in that: The distances between the axial centers of the heat exchange tubes of the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group on the radial cross section of the fluidized reaction device are independently 200-300 mm.

9. The fluidized bed reactor according to claim 1, characterized in that: The fluidized reactor further comprises a catalyst outlet.

10. The fluidized bed reactor according to claim 9, characterized in that: The catalyst outlet is arranged at the bottom of the reactor body.

11. The fluidized bed reactor according to claim 9, characterized in that: An air intake passage is provided between the third heat exchange tube group and the catalyst outlet.

12. The fluidized bed reactor according to claim 11, characterized in that: An outlet of the intake passage faces a catalyst outlet.

13. The fluidized bed reactor according to claim 1, characterized in that: The fluidized reaction device also includes an air inlet connected to the air inlet channel.

14. The fluidized bed reactor according to claim 13, characterized in that: The air inlet is arranged at one side of the lower part of the reactor body.

15. The fluidized bed reactor according to claim 1, characterized in that: The fluidized reaction device also includes a gas outlet.

16. The fluidized bed reactor according to claim 15, characterized in that: The gas outlet is arranged on one side of the upper part of the reactor body.

17. The fluidized bed reactor according to claim 15, characterized in that: The gas outlet is arranged at the upper part of the first heat exchange tube group.

18. The fluidized bed reactor according to claim 1, characterized in that: The fluidized reactor further comprises a catalyst inlet.

19. The fluidized bed reactor according to claim 18, characterized in that: The catalyst inlet is arranged at the top of the reactor body.

20. A method for producing thiophanate-methyl, characterized in that: The method is carried out using the fluidized bed reactor described in any one of claims 1 to 19.

21. The method according to claim 20, characterized in that The method comprises the following steps: (1) respectively introducing heat exchange media of different temperatures into the first heat exchange tube group, the second heat exchange tube group and the third heat exchange tube group; (2) The raw materials come into contact with the catalyst in the reactor body and a reaction occurs.

22. The method according to claim 21, characterized in that The heat exchange medium in step (1) includes heat transfer oil and / or molten salt.

23. The method according to claim 21, characterized in that The temperature of the heat exchange medium in the first heat exchange tube group is 310-340°C.

24. The method according to claim 23, characterized in that The temperature of the heat exchange medium in the first heat exchange tube group is 320-330°C.

25. The method according to claim 21, characterized in that The temperature of the heat exchange medium in the second heat exchange tube group is 270-300°C.

26. The method according to claim 25, characterized in that The temperature of the heat exchange medium in the second heat exchange tube group is 280-290°C.

27. The method according to claim 21, characterized in that The temperature of the heat exchange medium in the third heat exchange tube group is 240-270°C.

28. The method according to claim 27, characterized in that The temperature of the heat exchange medium in the third heat exchange tube group is 250-260°C.

29. The method according to claim 21, characterized in that The raw materials in step (2) include isophthalonitrile, chlorine and nitrogen.

30. The method according to claim 29, characterized in that The volume concentration of the isophthalonitrile is 5-7%.

31. The method according to claim 29, characterized in that The volume concentration of the chlorine gas is 25-45%.

32. The method according to claim 29, characterized in that The volume concentration of the nitrogen is 48-70%.

33. The method according to claim 29, characterized in that The mass space velocity of the isophthalonitrile is 0.05~0.1h -1 .

34. The method according to claim 21, characterized in that The catalyst includes coconut shell activated carbon.

35. The method according to claim 21, characterized in that The temperature in the first heat exchange tube group area in the reactor body is controlled to be 320-330°C.

36. The method according to claim 21, characterized in that The temperature in the second heat exchange tube group area in the reactor body is controlled to be 280-290°C.

37. The method according to claim 21, characterized in that The temperature in the third heat exchange tube group area in the reactor body is controlled to be 250-260°C.

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