Atomized feed reactor

Abstract

The utility model provides a kind of atomization feed reactor, the atomization feed reactor includes shell, stirring device and pressure atomization device;The stirring device includes stirring shaft, stirrer being arranged on the upper end of stirring shaft and stirring paddle being arranged on the lower part of stirring shaft;The stirrer is arranged on the outside upper portion of shell;The stirring shaft is inserted into shell interior and with the axial parallel of shell;The pressure atomization device includes at least 2 pressure atomization nozzles being arranged evenly along the circumferential of stirring shaft.The atomization feed reactor provided by the utility model can atomize raw materials from the top of reactor and spray out, significantly reduce the particle size of droplet, improve the mixing condition of raw materials, achieve the effect of reducing product particle size and promoting uniform product particle size.

Description

Technical Field

[0001] This utility model relates to the field of chemical equipment technology, and in particular to an atomizing feed reactor. Background Technology

[0002] In the field of chemical product synthesis, liquid-phase synthesis is a commonly used main synthesis method, which involves using multiple reaction solutions to carry out synthesis reactions in the same reactor. In actual industrial production, there are often high requirements for the synthesized products, such as strict requirements on the morphology, particle size and distribution of the synthesized solid products.

[0003] The liquid-liquid process is the main method for producing precipitated silica. For example, it involves using water glass solution and sulfuric acid solution, or ammonia solution and fluorosilicic acid / ammonium fluorosilicate solution, under specific temperature, concentration, and pH conditions in a reactor to produce precipitated silica slurry. Currently, one feedstock solution is typically fed into the reactor through a top liquid distributor, where it is mixed with another feedstock solution to produce precipitated silica. However, commonly used liquid distributors produce relatively large droplets, which can easily cause localized excessively high concentrations upon the addition of the other feedstock solution. This leads to uneven pH levels in localized areas, excessively rapid reaction rates, and the formation and aggregation of numerous precipitated silica crystal nuclei within a short period. This results in excessively large and unevenly distributed particle sizes, negatively impacting product quality. Current methods primarily aim to enhance stirring intensity and improve the uniformity of the mixture by changing the type of agitator and the installation method of baffles, thereby reducing the impact of uneven local concentrations. However, problems such as poor localized mixing, over-reaction, excessively large particle sizes, and uneven particle size distribution still exist, affecting the quality of the precipitated silica product.

[0004] CN111410199A discloses a production apparatus and preparation method for precipitated silica, comprising: a power unit, a reactor, a hollow shaft, dispersing blades, and a dispersing membrane; the power unit is located outside the reactor, while the hollow shaft, dispersing blades, and dispersing membrane are all located inside the reactor; the drive shaft of the power unit is connected to the hollow shaft to drive its rotation; the dispersing blades are hollow inside, and the hollow shaft connects to the dispersing blades; the dispersing blades are provided with vent holes communicating with their hollow interiors, and the dispersing membrane is connected to the surface of the dispersing blades, with one side of the dispersing membrane closely adhering to the dispersing blade and communicating with the vent holes; the hollow shaft is provided with a shaft gas inlet to sequentially supply gas to the hollow shaft, dispersing blades, and dispersing membrane. This apparatus promotes raw material dispersion through the design of the dispersing blade structure, but problems such as poor local mixing and over-reaction still exist.

[0005] CN204848286U discloses a reactor for preparing silica from water glass using ultrasonic and microwave assisted methods. The reactor includes a sodium silicate inlet, a sulfuric acid inlet, a microwave generator, an ultrasonic generator, a stirrer, a transmission device, a condenser reflux pipe, a support, and a reactor body. The microwave generator is installed around the reactor body. An ultrasonic generator and a pH sensor are installed at the bottom of the reactor body. A condenser reflux pipe is located at the top of the reactor body. The stirrer and a film remover are coaxial. The position of the film remover is adjustable and located at the reaction liquid surface. The sodium silicate inlet is located at the bottom of the reactor, and the sulfuric acid inlet is located at the edge of the stirrer. This reactor has a relatively high investment cost and a complex structure, which is not conducive to economical production.

[0006] Therefore, it is of great significance to provide a reactor that can enhance the mixing effect of raw materials, reduce the particle size of products, and promote the uniformity of product particle size. Utility Model Content

[0007] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide an atomizing feed reactor, which can atomize and spray the raw materials from the top of the reactor, significantly reducing the droplet size and improving the mixing method and mixing effect of the two raw material liquids during the reaction process.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] This utility model provides an atomizing feed reactor, which includes a shell, a stirring device, and a pressure atomizing device;

[0010] The stirring device includes a stirring shaft, a stirrer disposed at the upper end of the stirring shaft, and a stirring paddle disposed at the lower part of the stirring shaft.

[0011] The stirrer is located on the upper exterior of the housing;

[0012] The stirring shaft extends into the housing and is parallel to the axial direction of the housing;

[0013] The pressure atomizing device includes at least two pressure atomizing nozzles evenly arranged circumferentially along the stirring shaft.

[0014] In this invention, the stirring paddle is positioned below the liquid surface in the reactor, while the pressure atomizing nozzle is positioned inside the reactor and above the liquid surface. By uniformly arranging at least two pressure atomizing nozzles along the circumference of the stirring shaft, this invention achieves uniform spraying of raw material droplets along the circumference of the stirring shaft, significantly reducing the droplet size. When the sprayed raw material droplets fall onto the surface of another raw material liquid in the reactor, a rapid reaction occurs between multiple raw material liquids, which not only accelerates the mixing speed but also makes the pH value in the entire reaction system more uniform, reduces the product particle size, and makes the product more uniform, thereby improving product quality.

[0015] The pressure atomizing nozzle provided by this invention can atomize raw materials into small droplets with an average particle size of ≤100μm, and spray them in a conical shape onto the surface of another raw material liquid. Compared with the droplets produced by commonly used liquid distributors, the pressure atomizing nozzle provided by this invention can significantly reduce the explosive growth and agglomeration of product crystal nuclei caused by excessive local concentration of raw material liquid.

[0016] The pressure atomizing device includes at least two pressure atomizing nozzles evenly arranged circumferentially along the stirring shaft. For example, there may be two, three, four, five, or six nozzles, but it is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0017] Preferably, the height of the pressure atomizing nozzle accounts for 75-98% of the height of the housing, for example, it can be 75%, 76%, 78%, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96% or 90%, but is not limited to the listed values, and other unlisted values ​​within the range are also applicable.

[0018] The present invention preferably controls the height of the pressure atomizing nozzle to be within a specific range of the height of the shell, so that the small droplets sprayed by the pressure atomizing nozzle do not come into contact with the stirring shaft or the inner wall of the reactor before falling to the liquid surface, thereby avoiding the generation of large droplets and affecting the mixing effect.

[0019] Preferably, the distance between the pressure atomizing nozzle and the stirring shaft is 40-60% of the radius of the housing, for example, it can be 40%, 42%, 44%, 46%, 48%, 50%, 52%, 54%, 56%, 58% or 60%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0020] The present invention preferably controls the distance between the pressure atomizing nozzle and the stirring shaft within a specific range, so that the small droplets sprayed by the pressure atomizing nozzle do not come into contact with the stirring shaft or the inner wall of the reactor before falling to the liquid surface, thus avoiding the generation of large droplets and affecting the mixing effect.

[0021] Preferably, the inlet of the pressure atomizing nozzle is connected to a pressurizing pump; a first pneumatic regulating valve is provided between the inlet of the pressure atomizing nozzle and the pressurizing pump.

[0022] Preferably, a feed pipe is provided on one side of the bottom of the housing; a second pneumatic regulating valve is provided at the inlet of the feed pipe.

[0023] Preferably, a discharge pipe is provided on the bottom of the housing opposite to the feed pipe; a ball valve is provided at the outlet of the discharge pipe.

[0024] Preferably, the impeller blades have at least two layers, for example, two, three, or four layers, but are not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0025] Preferably, the inner sidewall of the shell is provided with at least two baffles spaced circumferentially, for example, two, three or four, but not limited to the listed values, and other unlisted values ​​within the range are also applicable; the axial direction of the baffles is parallel to the axial direction of the stirring shaft.

[0026] In this invention, the upper end of the baffle plate is positioned below the liquid surface inside the reactor.

[0027] In this invention, by setting the number of blade layers and baffles, the dispersion and homogenization of atomized droplets in another raw material liquid can be further accelerated, the mixing speed of the two raw material liquids can be increased, the pH value in the entire reaction system can be changed uniformly, and it is more conducive to obtaining products with nanoscale size and uniform particle size.

[0028] Preferably, an online pH detector is provided on the lower side of the housing.

[0029] In this invention, by setting an online pH detector, a first pneumatic regulating valve, and a second pneumatic regulating valve, the first and second pneumatic regulating valves can be associated with the online pH detector. When the online pH detector detects that the pH value of the liquid in the reactor is not within the set range, the feed flow rate of the first and second pneumatic regulating valves is adjusted to maintain the pH value within the set range.

[0030] Preferably, the height-to-diameter ratio of the shell is ≤1, for example, it can be 1, 0.9, 0.8, 0.7, 0.6 or 0.5, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0031] The present invention preferably controls the height-to-diameter ratio of the housing within a specific range, which can further increase the contact area between the small droplets sprayed by the pressure atomizing nozzle and the surface of the other raw material liquid, further promoting the uniform mixing of the raw materials, and achieving the effect of reducing the product particle size and improving the product uniformity.

[0032] The operation process of the atomizing feed reactor provided by this utility model for liquid-liquid reaction is as follows:

[0033] Raw material liquid A enters the reactor through the feed pipe at the bottom of the shell. The feed is added until the liquid surface of raw material liquid A is above the agitator. Raw material liquid B is pressurized by a pressurizing pump and enters the pressure atomizing nozzle. The raw material liquid B is sprayed onto the liquid surface of raw material liquid A through the pressure atomizing nozzle. At the same time, the agitator and baffle promote mixing until the reaction is completed. The resulting reaction slurry flows out through the discharge pipe at the bottom of the shell.

[0034] The above operating procedure is particularly applicable to the production process of silica.

[0035] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0036] The atomizing feed reactor provided by this utility model can significantly reduce the droplet size through the design of the pressure atomizing nozzle, improve the mixing method and mixing effect of the two raw material liquids during the reaction process, make the pH value in the entire reaction system more uniform, reduce the product particle size, make the product more uniform, and improve the product quality. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the atomizing feed reactor described in Embodiment 1 of this utility model.

[0038] In the figure: 1-shell; 2-pressure atomizing nozzle; 3-stirrer; 4-feed pipe; 5-discharge pipe; 6-stirring shaft; 7-stirring paddle; 8-online pH detector; 9-pressurizing pump; 10-first pneumatic regulating valve; 11-second pneumatic regulating valve; 12-baffle plate; 13-ball valve. Detailed Implementation

[0039] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0040] The present invention will now be described in further detail. However, the examples described below are merely 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 determined by the claims.

[0041] It should be understood that in the description of this utility model, the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0042] It should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0043] Those skilled in the art should understand that this utility model necessarily includes the necessary pipelines, conventional valves and general pump equipment for achieving complete process, but the above content is not the main inventive point of this utility model. Those skilled in the art can add layouts based on process flow and equipment structure selection. This utility model does not make any special requirements or specific limitations in this regard.

[0044] Example 1

[0045] This embodiment provides an atomizing feed reactor, the structural schematic of which is shown below. Figure 1 As shown, the atomizing feed reactor includes a shell 1, a stirring device, and a pressure atomizing device. The stirring device includes a stirring shaft 6, a stirrer 3 disposed at the upper end of the stirring shaft 6, and a stirring paddle 7 disposed at the lower part of the stirring shaft 6. The stirrer 3 is disposed above the outside of the shell 1. The stirring shaft 6 extends into the interior of the shell 1 and is parallel to the axial direction of the shell 1. The pressure atomizing device includes four pressure atomizing nozzles 2 evenly arranged along the circumference of the stirring shaft 6.

[0046] The inlet of the pressure atomizing nozzle 2 is connected to the pressurizing pump 9. A first pneumatic regulating valve 10 is provided between the inlet of the pressure atomizing nozzle 2 and the pressurizing pump 9. A feed pipe 4 is provided on one side of the bottom of the housing 1. A second pneumatic regulating valve 11 is provided at the inlet of the feed pipe 4. A discharge pipe 5 is provided on the bottom side of the housing 1 opposite to the feed port. A ball valve 13 is provided at the outlet of the discharge pipe 5. An online pH detector 8 is provided on one side of the lower part of the housing 1.

[0047] The first pneumatic regulating valve 10 and the second pneumatic regulating valve 11 are associated with the online pH detector 8. When the online pH detector 8 detects that the pH value of the liquid in the reactor is not within the set range, the feed flow rate of the first pneumatic regulating valve 10 and the second pneumatic regulating valve 11 is adjusted to maintain the pH value within the set range.

[0048] The height of the pressure atomizing nozzle 2 accounts for 90% of the height of the housing 1, the distance between the pressure atomizing nozzle 2 and the stirring shaft 6 accounts for 50% of the radius of the housing 1, the impeller 7 has two layers of blades, and four baffles 12 are arranged circumferentially on the inner sidewall of the housing 1. The axial direction of the baffles 12 is parallel to the axial direction of the stirring shaft 6, and the height-to-diameter ratio of the housing 1 is 1.

[0049] Example 2

[0050] This embodiment provides an atomizing feed reactor, which includes a shell, a stirring device, and a pressure atomizing device. The stirring device includes a stirring shaft, a stirrer disposed at the upper end of the stirring shaft, and a stirring paddle disposed at the lower part of the stirring shaft. The stirrer is disposed above the outside of the shell. The stirring shaft extends into the shell and is parallel to the axial direction of the shell. The pressure atomizing device includes two pressure atomizing nozzles evenly arranged along the circumference of the stirring shaft.

[0051] The inlet of the pressure atomizing nozzle is connected to a pressurizing pump. A first pneumatic regulating valve is provided between the inlet of the pressure atomizing nozzle and the pressurizing pump. A feed pipe is provided on one side of the bottom of the housing. A second pneumatic regulating valve is provided at the inlet of the feed pipe. A discharge pipe is provided on the bottom side of the housing opposite to the feed port. A ball valve is provided at the outlet of the discharge pipe. An online pH detector is provided on one side of the lower part of the housing.

[0052] The first and second pneumatic regulating valves are associated with an online pH detector. When the online pH detector detects that the pH value of the liquid in the reactor is not within the set range, the feed flow rate of the first and second pneumatic regulating valves is adjusted to maintain the pH value within the set range.

[0053] The height of the pressure atomizing nozzle accounts for 98% of the height of the housing, the distance between the pressure atomizing nozzle and the stirring shaft accounts for 40% of the radius of the housing, the impeller blades are 3 layers, the inner sidewall of the housing is provided with 2 baffles spaced circumferentially, the axial direction of the baffles is parallel to the axial direction of the stirring shaft, and the height-to-diameter ratio of the housing is 0.8.

[0054] Example 3

[0055] This embodiment provides an atomizing feed reactor, which includes a shell, a stirring device, and a pressure atomizing device. The stirring device includes a stirring shaft, a stirrer disposed at the upper end of the stirring shaft, and a stirring paddle disposed at the lower part of the stirring shaft. The stirrer is disposed above the outside of the shell. The stirring shaft extends into the shell and is parallel to the axial direction of the shell. The pressure atomizing device includes three pressure atomizing nozzles evenly arranged along the circumference of the stirring shaft.

[0056] The inlet of the pressure atomizing nozzle is connected to a pressurizing pump. A first pneumatic regulating valve is provided between the inlet of the pressure atomizing nozzle and the pressurizing pump. A feed pipe is provided on one side of the bottom of the housing. A second pneumatic regulating valve is provided at the inlet of the feed pipe. A discharge pipe is provided on the bottom side of the housing opposite to the feed port. A ball valve is provided at the outlet of the discharge pipe. An online pH detector is provided on one side of the lower part of the housing.

[0057] The first and second pneumatic regulating valves are associated with an online pH detector. When the online pH detector detects that the pH value of the liquid in the reactor is not within the set range, the feed flow rate of the first and second pneumatic regulating valves is adjusted to maintain the pH value within the set range.

[0058] The height of the pressure atomizing nozzle accounts for 75% of the height of the housing, the distance between the pressure atomizing nozzle and the stirring shaft accounts for 60% of the radius of the housing, the impeller blades are in two layers, and three baffles are arranged circumferentially on the inner sidewall of the housing. The axial direction of the baffles is parallel to the axial direction of the stirring shaft, and the height-to-diameter ratio of the housing is 0.5.

[0059] Example 4

[0060] This embodiment provides an atomizing feed reactor, which differs from Embodiment 1 only in that the distance between the pressure atomizing nozzle and the stirring shaft is 20% of the shell radius.

[0061] Example 5

[0062] This embodiment provides an atomizing feed reactor, which differs from Embodiment 1 only in that the distance between the pressure atomizing nozzle and the stirring shaft is 80% of the shell radius.

[0063] Comparative Example 1

[0064] This comparative example provides an atomizing feed reactor, which differs from Example 1 only in that the pressure atomizing device is replaced with a liquid distributor.

[0065] The atomizing feed reactors provided in Examples 1-5 and Comparative Example 1 are used in the production process of silica as follows:

[0066] A 20% ammonium fluorosilicate solution (A) is used as raw material A, with a flow rate of 1 m / s. It enters the reactor through the feed pipe at the bottom of the shell and is added until the surface of raw material A is above the agitator. A 20% ammonia solution (B) is used as raw material B, with a flow rate of 0.5 m / s. It is pressurized by a pressure pump and enters the pressure atomizing nozzle, which sprays it onto the surface of raw material A. At the same time, the agitator and baffles promote mixing. The reaction is carried out for 1 hour at a temperature of 30°C and a pressure of atmospheric pressure. The resulting reaction slurry flows out through the discharge pipe at the bottom of the shell.

[0067] Using the reactors of Examples 1-5 and Comparative Example 1, under the same raw material liquid and reaction conditions, the average particle size of the prepared silica is shown in Table 1.

[0068] Table 1

[0069] Example 1 57.4 Example 2 68.3 Example 3 64.4 Example 4 94.8 Example 5 96.1 Comparative Example 1 252.9

[0070] The following points can be observed from the data in Examples 1-5:

[0071] (1) In the preparation process of Examples 1-3, the raw material liquid was mixed more thoroughly, and the average particle size of the resulting silica product reached less than 68.3 nm, and the particle size distribution was relatively uniform.

[0072] (2) Compared with Examples 4-5, in Example 1, the distance between the pressure atomizing nozzle and the stirring shaft is 40% of the shell radius, compared with 20% and 80% in Examples 4-5, respectively. The average particle size in Example 1 is significantly lower than that in Examples 4-5. It can be seen that the present invention preferably controls the distance between the pressure atomizing nozzle and the stirring shaft, which can further promote uniform mixing, avoid the formation of large droplets, and thus further reduce the particle size of the product.

[0073] (3) Compared with Comparative Example 1, Comparative Example 1 replaced the pressure atomizing device with a liquid distributor. The average particle size in Example 1 was significantly lower than that in Comparative Example 1. It can be seen that the atomizing feed reactor provided by this utility model can reduce the product particle size and make the product more uniform.

[0074] In summary, the atomizing feed reactor provided by this utility model can atomize and spray the raw materials from the top of the reactor, significantly reducing the droplet size and improving the mixing method and mixing effect of the two raw material liquids during the reaction process.

[0075] The applicant declares that the above description is only a specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model fall within the protection and disclosure scope of the present utility model.

Claims

1. An atomizing feed reactor, characterized in that, The atomizing feed reactor includes a shell, a stirring device, and a pressure atomizing device; The stirring device includes a stirring shaft, a stirrer disposed at the upper end of the stirring shaft, and a stirring paddle disposed at the lower part of the stirring shaft. The stirrer is located on the upper exterior of the housing; The stirring shaft extends into the housing and is parallel to the axial direction of the housing; The pressure atomizing device includes at least two pressure atomizing nozzles evenly arranged circumferentially along the stirring shaft.

2. The atomizing feed reactor according to claim 1, characterized in that, The height of the pressure atomizing nozzle accounts for 75-98% of the height of the housing.

3. The atomizing feed reactor according to claim 1, characterized in that, The distance between the pressure atomizing nozzle and the stirring shaft is 40-60% of the shell radius.

4. The atomizing feed reactor according to claim 1, characterized in that, The inlet of the pressure atomizing nozzle is connected to a pressure pump; A first pneumatic regulating valve is provided between the inlet of the pressure atomizing nozzle and the pressurizing pump.

5. The atomizing feed reactor according to claim 1, characterized in that, A feed pipe is provided on one side of the bottom of the housing; A second pneumatic regulating valve is installed at the inlet of the feed pipe.

6. The atomizing feed reactor according to claim 5, characterized in that, A discharge pipe is provided on the bottom of the housing on the side opposite to the feed pipe; A ball valve is installed at the outlet of the discharge pipe.

7. The atomizing feed reactor according to claim 1, characterized in that, The impeller blades have at least two layers.

8. The atomizing feed reactor according to claim 1, characterized in that, The inner wall of the shell is provided with at least two baffles spaced circumferentially. The axial direction of the baffle plate is parallel to the axial direction of the stirring shaft.

9. The atomizing feed reactor according to claim 1, characterized in that, An online pH detector is provided on one side of the lower part of the housing.

10. The atomizing feed reactor according to claim 1, characterized in that, The height-to-diameter ratio of the shell is ≤1.

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