Low-screen residue carbon black reaction device

Abstract

The invention discloses a reaction device for carbon black with low screen residues. The reaction device comprises a reaction furnace, a first throat pipe, a backflow tail gas and hot flue gas heat exchange section and a raw oil and flue gas heat exchange section which are connected in sequence, wherein an inlet pipe is arranged at the front end of the reaction furnace; an oil gun connector coaxial with the inlet pipe is arranged in the center of the inlet pipe, a plasma torch connector deviating from the axis of the inlet pipe is annularly arranged on the outer wall of the inlet pipe, and an inclination angle larger than 0 degree and smaller than 90 degrees is formed between the plasma torch connector and the axis of the inlet pipe. A plurality of plasma torches are eccentrically arranged at the top of the reaction furnace according to a certain inclination angle to form a high-temperature tangential rotational flow field; carbon black raw oil is atomized through a plurality of gas atomization oil guns arranged in the axial direction and sprayed into a plasma high-temperature tangential rotational flow field, and oil gas and a high-temperature plasma carrier are subjected to a cracking reaction to generate carbon black flue gas; meanwhile, reaction hot tail gas is introduced into the upper part of the reaction furnace along the wall surface, and carbon black flue gas is restrained in the center of the reaction furnace by the hot tail gas, so that oil gas without carbon black is prevented from forming hard carbon on the wall surface of the reaction furnace.

Description

Technical Field

[0001] The invention relates to the field of carbon black production, in particular to a low-screen residue carbon black reaction device. Background Art

[0002] Preparation of carbon black by thermal plasma is an emerging technology in recent years. It uses high-temperature and high-enthalpy plasma to directly pyrolyze raw materials and obtain carbon black. Compared with traditional combustion, the advantage of thermal plasma carbon black is that no or only a small amount of air is required to participate in the reaction, and it has the advantages of high yield and low emissions. It is an ideal carbon black production process. The disadvantages are that the amount of thermal plasma gas is small, the energy is highly concentrated, and there is an obvious gradient in the flow field and temperature field in the reactor, which leads to uneven pyrolysis of oil and gas and the formation of carbon black. In particular, local high temperature easily leads to the formation of hard carbon, making the product quality controllable. The residue is generally high; in addition, compared with the traditional carbon black reactor plasma process, the reactor space is smaller, and the uneven speed and temperature will cause the incompletely reacted oil and gas to contact the reactor wall, making the reactor wall very easy to coke. Wall coking is not only an important source of residue, but also affects the continuous operation of the device when the coking is serious. At present, the application scenarios of carbon black have strict requirements on the content of sieve residues. Especially in the fields of battery conductive agents, the content of sieve residues is generally required to be no more than 20ppm for 45μm sieve residues. Therefore, whether the plasma carbon black process can meet the application of high-end market, the regulation of sieve residues is a technical problem that needs to be solved urgently. Summary of the invention

[0003] The purpose of the present invention is to provide a low-screening carbon black reaction device, which forms a high-temperature plasma tangential swirl field through an inlet pipe arranged at the front end of the reactor, increases the uniformity of the mixture of plasma and atomized oil and gas, and reduces the screen formation caused by local high temperature. In addition, a reflux pipe is added between the reactor and the heat exchange section of the reflux exhaust gas and hot flue gas, and the hot exhaust gas is introduced into the front end of the reactor in a tangential direction to form a hot air film, so that the carbon black flue gas is constrained in the center of the reactor, and the oil and gas that have not formed carbon black are prevented from forming hard carbon on the wall of the reactor, which solves the problem of coking in the carbon black reaction process in the prior art and greatly reduces the content of screen in the finished carbon black.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A low-screen residue carbon black reaction device comprises a reaction furnace, a first throat, a reflux exhaust gas and hot flue gas heat exchange section, and a raw oil and flue gas heat exchange section connected in sequence; wherein, an inlet pipe is provided at the front end of the reaction furnace; an oil gun interface coaxial with the inlet pipe is provided at the center of the inlet pipe, a plasma torch interface deviated from its axis is provided around the outer wall of the inlet pipe, and the plasma torch interface forms an inclination angle greater than 0° and less than 90° with the axis of the inlet pipe.

[0006] A further solution: the number of the plasma torch interfaces is at least four, and the plasma torch interfaces form an inclination angle of 30-60° with the axis of the inlet pipe.

[0007] A further solution: the number of the oil gun interfaces is at least three.

[0008] A further solution is that a reflux pipe is connected between the reaction furnace and the heat exchange section between the reflux exhaust gas and the hot flue gas.

[0009] A further solution is as follows: one end of the reflux pipe is connected to the front end of the reactor, and the other end is connected to the front end of the reflux exhaust gas and hot flue gas heat exchange section; the airflow enters the reflux pipe along a radial tangential direction to the reactor.

[0010] A further solution also includes a filter connected to the rear end of the crude oil and flue gas heat exchange section for separating carbon black and flue gas.

[0011] A further solution is that a first fan is connected between the filter and the rear end of the heat exchange section between the reflux exhaust gas and the hot flue gas.

[0012] A further solution includes a second fan connected to the exhaust port of the filter.

[0013] A further solution includes a second throat provided between the heat exchange section between the reflux exhaust gas and the hot flue gas and the heat exchange section between the raw oil and the flue gas.

[0014] A further solution: a quenching water interface is provided at the front end of the first throat pipe.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention adopts a scheme of eccentrically arranging multiple plasma jets at a certain inclination angle to form tangential mixing, thereby increasing the temperature and speed uniformity of the plasma high-temperature area. At the same time, multiple axially arranged gas atomization oil guns are used to supply oil. The oil volume of a single gun is small, and the uniformity of oil atomization is increased by multiple combinations, which helps to improve the uniformity and consistency of the mixing of oil, gas and plasma and reduce the formation of screen residues caused by local high temperature.

[0017] The tail gas formed by the thermal cracking reaction enters the front end of the reactor from the reflux pipe along the double-sided tangents from the reflux tail gas and hot flue gas heat exchanger, forming a swirling hot gas film, inhibiting the diffusion of oil and gas to the wall, effectively avoiding the formation of wall coking, and further reducing the screen residue.

[0018] The carbon black produced by the present invention has high structure, high specific surface area and high purity, and the 45μm sieve residue is less than 20PPm. The product has excellent conductivity and can be used in battery conductive agent, conductive and antistatic "rubber and plastic" products, antistatic oil, water-based coatings and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the present invention;

[0020] Figure 2 for Figure 1 Side view of

[0021] Figure 3 This is a photo of coking on the inner wall of the reactor in Comparative Example 3;

[0022] In the figure: 1-oil gun interface, 2-plasma torch interface, 3-reflux hot exhaust gas interface, 4-reactor, 5-quenching water interface, 6-reflux exhaust gas and hot flue gas heat exchange section, 7-raw oil and flue gas heat exchange section, 8-filter, 9-first fan, 10-second fan, 11-inlet pipe, 12-reflux pipe, 13-first throat pipe, 14-second throat pipe. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "inside", "outside", etc. are based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0025] See also Figure 1-3 In this embodiment, a low-screen carbon black reaction device comprises a reaction furnace 4, a first throat 13, a heat exchange section 6 for reflux exhaust gas and hot flue gas, and a heat exchange section 7 for raw oil and flue gas connected in sequence, wherein an inlet pipe 11 is provided at the front end of the reaction furnace 4; an oil gun interface 1 coaxial with the inlet pipe 11 is provided at the center of the inlet pipe 11, and a plasma torch interface 2 deviating from the axis is provided on the outer wall of the inlet pipe 11, and the plasma torch interface 2 forms an inclination angle with the inlet pipe 11. Through the special angle arrangement of the plasma torch interface 2, the plasma gas flow entering the reaction furnace 1 is subjected to a high-position tangential circular swirl field, and undergoes rapid heat exchange with the oil and gas entering from the oil gun interface 1, and a cracking reaction occurs to generate carbon black flue gas.

[0026] Furthermore, the number of plasma torch interfaces 2 is at least four, the inclination angle is 30-60°, and the interface is 10-30 mm away from the axis of the reaction furnace 4. The temperature of the plasma heat source is not less than 2500°C.

[0027] Furthermore, the number of oil gun interfaces 1 is at least three, and they are evenly arranged around the axis of the reaction furnace 4, the oil volume of a single oil gun does not exceed 100 kg / h, and the atomized oil and gas angle is 0-15°.

[0028] Furthermore, a reflux pipe 12 is connected between the reactor 4 and the reflux exhaust gas and hot flue gas heat exchange section 6 to introduce the hot exhaust gas formed by the cracking reaction into the reactor 4. Specifically, one end of the reflux pipe 12 is connected to the reflux hot exhaust gas interface 3 at the front end of the reactor 4, and the other end is connected to the front end of the reflux exhaust gas and hot flue gas heat exchange section 6; the reflux hot exhaust gas interface 3 is tangent to the side wall of the reactor 4, so that the hot exhaust gas flow can enter the furnace body along the tangential direction, forming a swirling hot air film to inhibit the diffusion of oil and gas to the wall. The reflux exhaust gas is heated to 850-950°C, and the reflux amount is 0.5-1.5 times the gas volume of the plasma heat source. It should be pointed out in particular that the rotation direction of the hot exhaust gas flow in the furnace body is the same as the rotation direction of the plasma torch to avoid disturbing the airflow direction in the furnace.

[0029] Furthermore, the reaction device also includes a filter 8 for separating carbon black and flue gas, which is connected to the rear end of the raw oil and flue gas heat exchange section 7. The filter is a bag filter. The separated carbon black falls from the bottom of the bag filter and is collected, and the waste gas and flue gas are discharged from the top of the bag filter, introduced into the boiler through a pipeline for combustion and then discharged into the atmosphere.

[0030] Furthermore, it also includes a second fan 10 connected to the exhaust port of the filter 8, which is used to introduce the exhaust gas into the boiler.

[0031] Furthermore, a first fan 9 is connected between the filter 8 of the reaction device and the rear end of the heat exchange section 6 for the reflux exhaust gas and hot flue gas.

[0032] Furthermore, it also includes a second throat 14 arranged between the reflux exhaust gas and hot flue gas heat exchange section 6 and the raw oil and flue gas heat exchange section 7, which is used to transitionally connect the two heat exchange sections.

[0033] The operating principle of the present invention is as follows:

[0034] Oil, gas and plasma enter the reactor 4 from the inlet pipe 11. The inlet pipe 11 is the rapid mixing reaction zone A of the atomized raw oil and the high-temperature plasma heat source. The main body of the reactor 4 is the main reaction zone B for carbon black generation. A complete thermal cracking reaction occurs in the reaction zone B. The high-temperature flue gas after cracking enters the carbon black termination reaction zone C (i.e., the first throat 13). The reaction is terminated by cooling the reaction by externally connecting low-temperature deionized water through the quenching water interface 5. The flue gas after quenching is further cooled by heat exchange through the reflux tail gas and hot flue gas heat exchange section 6 and the raw oil and flue gas heat exchange section 7. The carbon black flue gas enters the bag filter for separation. The hot tail gas in the reflux tail gas and hot flue gas heat exchange section 6 passes through the reflux pipe 12 and the reflux hot tail gas interface 3 in a tangential direction and enters the front end of the reactor 4, forming a hot gas film to isolate the high-temperature oil and gas from contacting the inner wall of the reactor 4, avoiding the formation of hard carbon on the furnace wall, and increasing the screen residue in the carbon black finished product.

[0035] The specific structure of the carbon black reaction device used in the following Examples 1-3 is as follows: Figure 1-2 shown.

[0036] Example 1

[0037] The carbon black reaction device in this embodiment uses four 125kW nitrogen plasma torches (total power 500kW), which are connected to the corresponding plasma torch interfaces 2 respectively. The total gas volume of the plasma torch is 200Nm 3 / h, 4 torches are evenly distributed at the front end of the reactor 4 at an angle of 45° and an eccentricity of 10mm; the crude oil is arranged in an equilateral triangle with 3 nitrogen atomizing oil guns, which are connected to the oil gun interface 1 one by one. The oil volume of each oil gun is 30kg / h, the oil pressure is 0.5MPa, the atomizing nitrogen pressure is 0.6MPa, and the atomizing gas volume of each gun is 6Nm 3 / h, oil-gas atomization injection angle 0°; the amount of reflux exhaust gas is 0.5-1.5 times the amount of heat source gas, i.e. 100-300Nm 3 / h, the reflux tail gas preheating temperature is 850-950℃. The carbon black product collected by the bag filter was tested for performance. The test items and results are shown in Table 1.

[0038] Example 2

[0039] The carbon black reaction device in this embodiment uses four 250kW nitrogen plasma torches (total power 1000kW), which are connected to the corresponding plasma torch interfaces 2 respectively, and the total gas volume of the plasma heat source is 400Nm 3 / h, 4 torches are evenly distributed on the top of the reactor at an angle of 45° and an eccentricity of 10mm; the crude oil is arranged in an equilateral triangle with 3 nitrogen atomizing oil guns, which are connected to the oil gun interface 1 one by one. The oil volume of each oil gun is 50kg / h, the oil pressure is 0.5MPa, the atomizing nitrogen pressure is 0.6MPa, and the atomizing gas volume of each gun is 8Nm 3 / h, oil-gas atomization injection angle 0°; the amount of reflux exhaust gas is 0.5-1.5 times the amount of heat source gas, i.e. 200-600Nm 3 / h, the reflux tail gas preheating temperature is 850-950℃. The carbon black product collected by the bag filter was tested for performance. The test items and results are shown in Table 1.

[0040] Example 3

[0041] The carbon black reaction device in this embodiment uses 4 345kW nitrogen plasma torches (total power 1500kW), which are respectively connected to the corresponding plasma torch interface 2, the total gas volume of the plasma heat source is 400Nm3 / h, and the 4 torches are evenly distributed on the top of the reactor at an angle of 45° and eccentricity of 10mm; the raw oil uses 3 nitrogen atomization oil guns arranged in an equilateral triangle axis, which are connected to the oil gun interface 1 one by one, the oil volume of each oil gun is 50kg / h, the oil pressure is 0.5MPa, the atomization nitrogen pressure is 0.6MPa, the atomization gas volume of each gun is 8Nm3 / h, and the oil and gas atomization injection angle is 0°; the reflux tail gas volume is 0.5-1.5 times the heat source gas volume, i.e. 200-600Nm3 / h, and the reflux tail gas preheating temperature is 850-950℃. The carbon black product collected by the bag filter is tested for performance, and the test items and results are shown in Table 1.

[0042] Comparative Example 1

[0043] This comparative example is the same as Example 2 except that only one oil gun interface is provided. The oil gun interface is connected to a nitrogen atomizing oil gun arranged on the axis, with an oil volume of 150 kg / h, an oil pressure of 0.5 MPa, an atomizing nitrogen pressure of 0.6 MPa, an atomizing gas volume of 24 Nm3 / h, and an oil and gas atomizing spray angle of 0°. The carbon black product collected by the bag filter was subjected to a performance test, and the test items and results are shown in Table 1.

[0044] Comparative Example 2

[0045] The comparative example is the same as Example 2 except for the setting angle of the plasma torch interface 2. The plasma torch interface 2 is perpendicular to the central axis of the reactor 4, points to the axis of the reactor 4, and is evenly distributed at the front end of the reactor 4. The carbon black product collected by the bag filter is subjected to performance testing, and the test items and results are shown in Table 1.

[0046] Comparative Example 3

[0047] This comparative example is the same as Example 2 except that the reflux pipe 12 is not provided. The carbon black product collected by the bag filter is subjected to a performance test, and the test standard refers to GB / T 3780.21-2016 Carbon black Part 21: Determination of sieve residue by water flushing method; the test results are shown in Table 1.

[0048] Table 1

[0049]

[0050]

[0051] Although this specification is described according to implementation modes, not every implementation mode includes only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0052] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent changes made according to the scope of the claims of the present application are within the protection scope of the claims of the present application.

Claims

1. A low residue carbon black reaction device, characterized in that: The invention comprises a reaction furnace (4), a first throat (13), a heat exchange section for reflux exhaust gas and hot flue gas (6), and a heat exchange section for raw oil and flue gas (7) which are connected in sequence; wherein an inlet pipe (11) is provided at the front end of the reaction furnace (4); an oil gun interface (1) coaxial with the inlet pipe (11) is provided at the center thereof, a plasma torch interface (2) deviating from the axis thereof is provided around the outer wall of the inlet pipe (11), and an inclination angle of greater than 0° and less than 90° is formed between the plasma torch interface (2) and the axis of the inlet pipe (11).

2. The low residue carbon black reaction device according to claim 1, characterized in that: The number of the plasma torch interfaces (2) is at least four; the plasma torch interfaces (2) form an inclination angle of 30-60° with the axis of the inlet pipe (11).

3. The low residue carbon black reaction device according to claim 1, characterized in that: The number of the oil gun interfaces (1) is at least three.

4. The low residue carbon black reaction device according to claim 1, characterized in that: A reflux pipe (12) is connected between the reaction furnace (4) and the reflux tail gas and hot flue gas heat exchange section (6).

5. The low residue carbon black reaction device according to claim 4, characterized in that: One end of the recirculation pipe (12) is connected to the front end of the reaction furnace (4), and the other end is connected to the front end of the recirculation exhaust gas and hot flue gas heat exchange section (6); the airflow enters the recirculation pipe (12) along a radially tangential direction to the reaction furnace (4).

6. The low residue carbon black reaction device according to claim 1, characterized in that: It also includes a filter (8) connected to the rear end of the crude oil and flue gas heat exchange section (7) for separating carbon black and flue gas.

7. The low residue carbon black reaction device according to claim 6, characterized in that: A first fan (9) is connected between the filter (8) and the rear end of the return exhaust gas and hot flue gas heat exchange section (6).

8. The low residue carbon black reaction device according to claim 6, characterized in that: It also includes a second fan (10) connected to the exhaust port of the filter (8).

9. The low residue carbon black reaction device according to claim 1, characterized in that: It also includes a second throat (14) arranged between the reflux exhaust gas and hot flue gas heat exchange section (6) and the raw oil and flue gas heat exchange section (7).

10. The low residue carbon black reaction device according to claim 1, characterized in that: A quenching water interface (5) is provided at the front end of the first throat pipe (13).

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