Vaporization device for producing white carbon black

Abstract

The utility model discloses a vaporization device for producing white carbon black, which comprises a vaporizer for vaporizing methyl trichlorosilane and a waste liquid tank for storing waste liquid, a waste liquid outlet of the vaporizer is connected with a waste liquid main pipeline, the waste liquid main pipeline is divided into a plurality of waste liquid branches, the other ends of the waste liquid branches are connected with the waste liquid tank, and the waste liquid tank is connected with the vaporizer. A discharge main valve is arranged on the waste liquid main pipeline, and a branch valve for control is arranged on each waste liquid branch. The discharging main valve and the branch valves for controlling the branches are arranged between the pipelines of the vaporizer and the waste liquid tank, so that online discharging of waste liquid in the vaporization process of methyl trichlorosilane can be realized, and long-period accumulation is avoided.

Description

Technical Field

[0001] The present application relates to a production device for white carbon black, and in particular to a vaporization device for producing white carbon black. Background Art

[0002] Fumed silica (scientific name: fumed silica or aerosol silica) is an amorphous powder material obtained by high-temperature hydrolysis of chlorosilane in a hydrogen-oxygen flame. The primary particle size is about 7 to 40 nm and the specific surface area is 50 to 380 m 2 / g, relative density (2.319~2.653)×10 3 kg / m 3 , melting point is 1750℃, insoluble in water and acid, soluble in strong alkali and hydrofluoric acid. The product is loose, white powder in the uncompressed state, and loose flakes after compression. It is odorless, tasteless, non-toxic, and has strong moisture absorption capacity during storage. Due to its excellent properties such as porosity, large specific surface area, high dispersibility, light weight, good chemical stability, high temperature resistance, non-combustion, and good electrical insulation, the product is widely used in silicone rubber, adhesives, paints and coatings, inks and copy inks, unsaturated polyester resins, composite materials, medicine, papermaking, food, cosmetics, chemical mechanical polishing and other industries.

[0003] In the production process of fumed silica, monomethyltrichlorosilane (CH3SiCl3) is one of the main raw materials required for production. The liquid phase monomethyltrichlorosilane is converted into gas phase through a vaporizer, and then fully mixed with raw materials hydrogen and air through a mixer and subjected to high-temperature hydrolysis reaction in the combustion chamber. The reaction principle is as follows:

[0004] Main reaction: CH3SiCl3+2H2+3O2→SiO2+CO2+3HCL+2H2O (under high temperature conditions)

[0005] Side reaction: CH3SiCl3+2O2→SiO2+CO2+3HCL (under high temperature conditions)

[0006] The existing production process is to convert liquid monomethyltrichlorosilane into gas phase through a monomethyl vaporizer, and then fully mix it with raw materials hydrogen and air through a mixer before undergoing a high-temperature hydrolysis reaction in a combustion chamber. As the production cycle extends, the appearance and purity of the material at the bottom of the monomethyl vaporizer will deteriorate. The lack of constant heat exchange in the gas phase monomethyl will cause premature hydrolysis due to temperature differences. During the production process, the monomethyl with impurities will react in the combustion chamber along with the vaporized monomethyl, thereby being brought into the silica product, reducing the quality of the gas phase silica and affecting its performance in high-end application fields such as electronics, pharmaceuticals, cosmetics and other industries.

[0007] The application number is 201711123068.9, and the name is a production process and device for nano-fumed silica. The purpose of the invention is to provide a production process and equipment for fumed silica. Since the raw material chlorosilane of fumed silica is very easy to react with water during the long-term production process, the water content in the system must be controlled. At the same time, in order to obtain nano-scale silica particles, the gaseous raw material must enter the reactor at a high speed and pressure. If the flow rate is too low, the production capacity will be limited. If the flow rate is too high, the reactor structure will be due to the particularity of the above process, resulting in certain difficulties in producing high-quality fumed silica. To solve the above problems, the technical solution adopted by the invention is: the raw material chlorosilane is heated to a vaporized state by steam, further mixed with preheated air through a static online mixer, and then mixed with hydrogen, further heated to 100-500°C, and passed through a reactor into a closed reaction furnace at a certain flow rate, ignited and burned and hydrolyzed at the reactor port, and the temperature is controlled at 1000-1800°C to obtain a white powder, which is then aggregated, separated, and deacidified to obtain white fluffy nano-gas-phase silica.

[0008] The application number is CN02149782.6, and the name is a method for preparing highly dispersed nano silicon dioxide. The invention discloses a method for preparing highly dispersed nano silicon dioxide, wherein oxygen, hydrogen, and organic halogenated silane are continuously fed into a combustion nozzle in a certain ratio to perform combustion reaction in a reaction chamber, and a protective gas is simultaneously fed into the reaction chamber, and the halogenated silane uses the water generated by the combustion and the heat generated to perform high-temperature hydrolysis and condensation reaction, and the reaction product is subjected to post-treatment processes such as aggregation, gas-solid separation, and deacidification to obtain the nano silicon dioxide prepared by the invention, and the primary particle size is between 7 and 40 nm, and the specific surface area is between 100 and 400 m 2 / g. The combustion nozzle and reaction chamber of the present invention can prevent the deposition of nano-silicon dioxide on the wall of the reaction chamber during the production process, thereby improving the continuity of production and the stability of the product. The calcination deacidification process adopted by the present invention introduces water vapor and inert gas at the same time to ensure that the pH value of the product after deacidification is between 3.8 and 4.5. The entire production process forms a closed system without dust pollution, and the yield of silicon dioxide is greater than 99%.

[0009] In the existing production technology, the heavy components and impurities at the bottom of the A vaporizer can only be discharged and packaged externally during the system shutdown and maintenance period, and it is impossible to achieve online waste discharge during normal production. The gas phase temperature after the liquid A vaporized cannot be kept constant and filtered again. The raw material A contains impurities or is hydrolyzed in advance, which may be directly mixed into the final silica product, reducing the purity of silica, resulting in production difficulties and unstable product quality. The problems affect its performance in high-end application fields such as electronics, pharmaceuticals, cosmetics and other industries. Therefore, it is necessary to invent a new vaporization process for the production of raw materials for gas-phase silica to achieve online waste discharge and ensure the constant temperature of the gas phase A during normal production. Summary of the invention

[0010] The purpose of the present application is to provide a vaporization device for producing white carbon black capable of discharging waste liquid online.

[0011] Another object of the present application is to provide a device for improving the quality of white carbon black products.

[0012] To achieve the above objectives, the technical solution adopted in the present application is: to provide a vaporization device for producing white carbon black, including a vaporizer for vaporizing monomethyltrichlorosilane and a waste liquid tank for storing waste liquid, the waste liquid outlet of the vaporizer is connected to a waste liquid main pipeline, the waste liquid main pipeline is divided into multiple waste liquid branches, the other end of the waste liquid branch is connected to the waste liquid tank, the waste liquid main pipeline is provided with a discharge main valve, and each of the waste liquid branches is provided with a branch valve for control.

[0013] As a preference, each of the branch valves is arranged at an end away from the main discharge valve, so that the pipeline between the main discharge valve and each of the branch valves is suitable for storing waste liquid.

[0014] As another preference, the vaporizer is provided with a pressure regulating system to maintain a stable pressure in the vaporizer.

[0015] As another preference, the vaporizer is further provided with a safety protection facility, which is suitable for relieving pressure when the internal pressure exceeds a set value.

[0016] As another preference, the vaporizer is provided with a temperature and pressure detection gauge to facilitate real-time detection of the temperature and pressure inside the vaporizer.

[0017] As another preference, the gas phase outlet of the vaporizer is connected to a plurality of heat exchangers connected in series, and the heat exchangers are suitable for further heating the monomethyltrichlorosilane.

[0018] As another preference, the temperature of the heat exchanger is set at 120-130°C.

[0019] As another preference, the inlet and outlet of each heat exchanger are provided with a temperature sensor to detect the temperature change of the monomethyltrichlorosilane in real time.

[0020] As another preference, an actuator is provided at the inlet of the heat exchanger, and the actuator is suitable for adjusting the temperature of the monomethyltrichlorosilane flowing out of the heat exchanger.

[0021] Further preferably, a heating filter is provided, the outlet of the heat exchanger is connected to the inlet of the heating filter, and the heating filter is suitable for filtering the impurities in the monomethyltrichlorosilane again.

[0022] Compared with the prior art, the beneficial effects of this application are:

[0023] (1) The present application can achieve online discharge of waste liquid during the vaporization of monomethyltrichlorosilane by setting a main discharge valve and branch valves for controlling each branch between the pipeline of the vaporizer and the waste liquid tank, thereby avoiding long-term accumulation;

[0024] (2) The present application provides multiple heat exchangers in series and a heating filter after the heat exchanger, so that the vaporization of monomethyltrichlorosilane is more complete and the purity is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a process flow chart of an embodiment of the present application.

[0026] In the figure: 10, vaporizer; 11, main discharge valve; 12, branch valve; 121, first branch valve; 122, second branch valve; 20, waste liquid tank; 30, heat exchanger; 40, heating filter. DETAILED DESCRIPTION

[0027] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0028] In the description of the present application, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of narrating the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as limiting the specific scope of protection of the present application.

[0029] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0030] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0031] like Figure 1 As shown, the vaporization device for producing white carbon black of the present application includes a vaporizer 10, a waste liquid tank 20, a heat exchanger 30 and a heating filter 40. The waste outlet of the vaporizer 10 is connected to the waste liquid tank 20, and the waste liquid outlet of the vaporizer 10 is connected to the waste liquid main pipeline. The waste liquid main pipeline is further divided into multiple waste liquid branches, and the waste liquid branches are collectively connected to the waste liquid inlet of the waste liquid tank. The waste liquid main pipeline is provided with a discharge main valve 11 for controlling the opening or closing of the waste liquid main pipeline, and each waste liquid branch is provided with a branch valve 12 for controlling the opening or closing of the waste liquid branch.

[0032] The present application can realize the online discharge of waste materials during the vaporization process of monomethylchlorosilane by setting the above-mentioned main discharge valve 11 and the branch valve 12, and can effectively avoid the accumulation of more and more impurities at the bottom of the vaporizer 10 during a long production process, and the monomethyltrichlorosilane containing impurities enters the combustion chamber for reaction, which reduces the purity of the produced silicon dioxide, resulting in difficult production control, unstable product quality and other effects.

[0033] Liquid monomethyltrichlorosilane enters the vaporizer 10, is heated to above the boiling point in the vaporizer 10, and is converted into gaseous monomethyltrichlorosilane, which becomes the raw material for the subsequent production of white carbon black by the gas phase method.

[0034] During the long-term start-up process of vaporizing monomethyltrichlorosilane, some heavy components or low-volatility impurities contained in monomethyltrichlorosilane will be deposited at the bottom of the vaporizer 10. In the present application, a waste outlet is provided at the bottom of the vaporizer 10, and the waste outlet is connected to the waste tank 20.

[0035] A plurality of connecting pipelines are arranged between the vaporizer 10 and the waste liquid tank 20, wherein a main discharge valve 11 is arranged at the outlet of the vaporizer 10, serving as a main valve for controlling the outflow of waste liquid from the vaporizer 10. When the main discharge valve 11 is opened, the waste liquid can flow out from the bottom of the vaporizer 10, and when the main discharge valve 11 is closed, the waste liquid cannot flow out from the waste liquid main pipeline.

[0036] like Figure 1 As shown, two pipeline branches are arranged between the waste liquid outlet of the vaporizer 10 and the waste liquid inlet of the waste liquid tank 20, and are respectively provided with a first branch valve 121 and a second branch valve 122. Each branch valve 12 can control the connectivity of the branch. When the main discharge valve 11 is opened, and the first branch valve 121 and the second branch valve 122 are opened, the waste liquid can flow out from the bottom of the vaporizer 10, and at the same time enter the waste liquid tank 20 through the pipeline controlled by the first branch valve 121 and the pipeline controlled by the second branch valve 122.

[0037] The present application realizes the online discharge of waste liquid by setting the switch of the discharge main valve 11 and the branch valve 12. In one embodiment, the online discharge operation of the waste liquid is as follows: during the discharge, the discharge main valve 11 is first opened, and the first branch valve 121 and the second branch valve 122 are closed at the same time, so that the waste liquid inside the vaporizer 10 can flow out from the bottom of the vaporizer 10 and enter the pipeline, but due to the closure of the first branch valve 121 and the second branch valve 122, the waste liquid remains in the pipeline and does not enter the waste liquid tank 20. After a certain period of circulation, the discharge main valve 11 is closed, the waste liquid stops flowing out of the vaporizer 10, and after the waste liquid is cooled in the pipeline, the first branch valve 121 and the second branch valve 122 are opened, and the waste liquid in the pipeline can flow into the waste liquid tank 20.

[0038] By setting the switch of the discharge main valve 11 and the branch valve 12, the waste liquid will not flow directly into the waste liquid tank 20 after flowing out of the vaporizer 10, so as to avoid the inability to control the outflow of the waste liquid. The outflow of the waste liquid can be controlled by the opening time of the discharge main valve 11, so as to avoid a large amount of monomethyltrichlorosilane flowing into the waste liquid tank 20 and causing waste. The waste liquid entering the waste liquid tank 20 can be transported to the upstream workshop by a pump for re-purification and reuse.

[0039] In some embodiments, the vaporizer 10 includes a shell, a head is provided on the top of the shell, and evenly arranged vertical tubes are provided in the middle of the shell, one end of the tube is the tube outlet, and the other end of the tube is the tube inlet, an outlet for gas phase monomethyltrichlorosilane is provided on the top of the head, an inlet for liquid phase monomethyltrichlorosilane is provided in the middle of the shell, and a regulating valve for controlling the liquid speed and flow is provided in the liquid phase inlet pipeline.

[0040] In some embodiments, the vaporizer 10 is provided with a pressure regulating system, which may include components such as a throttle valve and a pressure regulating valve, so as to keep the pressure of the vaporized monomethyltrichlorosilane stable.

[0041] The vaporizer 10 is suitable for being provided with temperature and pressure detection instruments to monitor the temperature and pressure changes inside the vaporizer 10 in real time. In addition, the vaporizer 10 is usually also provided with safety protection facilities, such as a safety valve and an emergency shut-off device. The safety valve can automatically release the pressure when the internal pressure exceeds the set value to prevent overpressure. The emergency shut-off device can quickly cut off the input of liquid monomethyltrichlorosilane in abnormal situations to ensure safety.

[0042] In some embodiments, the vaporization process of the raw material for producing gas-phase silica in the present application also includes multiple heat exchangers 30, and the gas phase outlet of monomethyltrichlorosilane of the vaporizer 10 is connected to the inlet of the heat exchanger 30. The heat exchanger 30 further heats and vaporizes the monomethyltrichlorosilane to further ensure the gas phase temperature and purity of the gas phase monomethyltrichlorosilane.

[0043] In some preferred embodiments, multiple heat exchangers 30 are connected in series to ensure that monomethyltrichlorosilane can remain in a gas phase before the reaction of producing white carbon black. In some embodiments, temperature sensors are installed at the inlet and outlet of the heat exchanger 30 to monitor the temperature change of monomethyltrichlorosilane in real time.

[0044] In some embodiments, a controller is provided for receiving the signal of the temperature sensor on the heat exchanger 30. The controller can also analyze and compare the received signal with the temperature of the preset temperature set point. The controller can be a programmable logic controller (PLC) or a distributed control system (DCS) as a core control unit. In the control strategy of the controller, a master control heat exchanger 30 can be designed, which can directly adjust the heating of one or more heat exchangers 30 to keep the outlet temperature constant.

[0045] In some embodiments, when the outlet temperature of the heat exchanger 30 is greatly affected by the heat source flow rate, the outlet temperature of the heat exchanger 30 can be indirectly controlled by adjusting the heat source flow rate. A valve and an actuator for controlling the valve are provided at the gas phase inlet of monomethyltrichlorosilane of the heat exchanger 30, and the opening of the gas phase flow inlet gate can be adjusted according to the output signal of the controller, or the flow rate of the heat source can be adjusted, so as to realize automatic temperature adjustment.

[0046] In some preferred embodiments, the vaporization device for producing white carbon black in the present application further includes a heating filter 40, which filters impurities after the monomethyltrichlorosilane is heated and vaporized again, further ensuring the purity of the de-reacted monomethyltrichlorosilane raw material, which is beneficial to improving the quality of the produced white carbon black.

[0047] In some specific embodiments, liquid monomethyltrichlorosilane is delivered to the vaporizer 10 by a delivery pump for heating and vaporization. The liquid level of the vaporizer 10 is set to 35% to 65%, the pressure is set to 0.1 to 0.2 MPa, and the safety valve trip pressure is set to 0.35 MPa. When the internal pressure of the vaporizer 10 exceeds 0.35 MPa, the safety valve will automatically trip and release the pressure. The vaporized gaseous monomethyltrichlorosilane flows out from the top and is constantly exchanged with heat through 16 heat exchangers 30 connected in series. After filtering impurities through the heating filter 40, it enters the mixer and is mixed with other production raw materials. The temperature of the heat exchanger 30 is set to 120 to 130°C.

[0048] The vaporization device for producing white carbon black of the present application can realize online discharge of waste materials during the production process without stopping the production to discharge materials. A plurality of heat exchangers 30 and heating filters 40 are also designed to ensure the quality of vaporized monomethyltrichlorosilane, which is beneficial to improving the product quality of white carbon black.

[0049] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A vaporization device for producing white carbon black, characterized in that: The invention comprises a vaporizer for vaporizing monomethyltrichlorosilane and a waste liquid tank for storing waste liquid, wherein the waste liquid outlet of the vaporizer is connected to a waste liquid main pipeline, the waste liquid main pipeline is divided into a plurality of waste liquid branches, the other end of each waste liquid branch is connected to the waste liquid tank, a discharge main valve is arranged on the waste liquid main pipeline, and each waste liquid branch is arranged with a branch valve for control.

2. The vaporization device for producing white carbon black according to claim 1, characterized in that: Each of the branch valves is arranged at an end away from the main discharge valve, so that the pipeline between the main discharge valve and each of the branch valves is suitable for storing waste liquid.

3. The vaporization device for producing white carbon black according to claim 2, characterized in that: The vaporizer is provided with a pressure regulating system to maintain a stable pressure in the vaporizer.

4. The vaporization device for producing white carbon black according to claim 3, characterized in that: The vaporizer is also provided with a safety protection facility, which is suitable for relieving pressure when the internal pressure exceeds a set value.

5. The vaporization device for producing white carbon black according to claim 4, characterized in that: The vaporizer is provided with a temperature and pressure detection gauge to detect the temperature and pressure inside the vaporizer in real time.

6. The vaporization device for producing white carbon black according to claim 2, characterized in that: The gas phase outlet of the vaporizer is connected to a plurality of heat exchangers connected in series, and the heat exchangers are suitable for further heating the monomethyltrichlorosilane.

7. The vaporization device for producing white carbon black according to claim 6, characterized in that: The temperature of the heat exchanger is set at 120-130°C.

8. The vaporization device for producing white carbon black according to claim 6, characterized in that: The inlet and outlet of each heat exchanger are provided with a temperature sensor to detect the temperature change of the monomethyltrichlorosilane in real time.

9. The vaporization device for producing white carbon black according to claim 6, characterized in that: The inlet of the heat exchanger is provided with an actuator, which is suitable for adjusting the temperature of the monomethyltrichlorosilane flowing out of the heat exchanger.

10. The vaporization device for producing white carbon black according to claim 6, characterized in that: A heating filter is also provided, the outlet of the heat exchanger is connected to the inlet of the heating filter, and the heating filter is suitable for filtering impurities in the monomethyltrichlorosilane again.

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