JPH09241528A - Process and apparatus for production carbon black - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for efficiently producing carbon black in a high yield without producing carbon dioxide and provide an apparatus therefor. SOLUTION: In this process, a hydrocarbon feedstock which is liq. or solid at normal temp. is thermally vaporized, then introduced together with a carrier gas into an externally heated thermal decomposition oven kept in an oxygenfree atmosphere, and heated to a specified temp. to be thermally decomposed. This apparatus comprises a feed vaporizer 6 for thermally vaporizing a hydrocarbon feedstock which is liq. or solid at normal temp., a feed nozzle 12 for introducing the hydrocarbon vapor and a carrier gas into a thermal decomposition oven, an externally heated thermal decomposition oven 13 for thermally decomposing the introduced hydrocarbon vapor, a cooling pipe 18 for cooling the resultant thermal decomposition gas, and a separator 19 for separating carbon black from the decomposition gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carbon black production method and production apparatus capable of efficiently producing high-purity carbon black with a high production yield.

[0002]

2. Description of the Related Art Carbon black production methods are roughly classified into a thermal decomposition method and an incomplete combustion method. The thermal decomposition method includes a thermal method in which heating and thermal decomposition are periodically repeated using natural gas, and an acetylene method. There is an acetylene method in which the acetylene gas is continuously pyrolyzed by utilizing the fact that the pyrolysis of is an exothermic reaction.

On the other hand, the incomplete combustion method burns fuel and thermally decomposes the raw material hydrocarbons by the combustion heat to produce carbon black. It is classified into a gas furnace method and an oil furnace method depending on the kind of the raw material. However, most of the carbon blacks for rubber and color are currently manufactured by the oil furnace method.

A basic production system of the oil furnace method uses a reaction furnace in which a cylindrical combustion area lined with refractory bricks, a reaction area and a reaction stop area are coaxially connected, and hydrocarbons for fuel are used in the combustion area. Is combusted with excess air to generate high temperature combustion gas, and this high temperature combustion gas flow is guided to the subsequent reaction zone.In the reaction zone, the feed hydrocarbon oil is introduced into the high temperature combustion gas flow, and part of the feed oil is Carbon black is produced by burning and thermally decomposing the rest. The gas stream containing the produced carbon black is rapidly cooled in the reaction stop region at the rear of the furnace to terminate the reaction, and finally is collected in the collecting step.

In the above process, a part of the feedstock hydrocarbon oil is pyrolyzed into carbon black and hydrogen, and at the same time, a part of it is burned and decomposed into carbon monoxide,
Carbon dioxide, water vapor, etc. are generated. Therefore, it is a part of the feedstock hydrocarbon oil that is converted to carbon black, generally 40 to 80% of the carbon in the feedstock hydrocarbon oil is converted to carbon black, and the balance is carbon monoxide, carbon dioxide, It becomes a gaseous combustion product containing traces of methane and methylene as well as water vapor. These gaseous combustion products separate and collect carbon black, burn it with a large amount of air, convert it into carbon dioxide, and release it to the outside of the system.

[0006]

As described above, in the oil furnace method, since a part of carbon in the raw hydrocarbon oil is converted into carbon black, the production yield of carbon black is low and the global environment is low. There is a problem that a large amount of harmful carbon dioxide is released in terms of conservation. Further, since the produced carbon black is contained in a large amount of gas flow, a large-scale device is required for its separation and collection, and there is a drawback that the production efficiency is low.

The problem to be solved by the present invention is solved by solving the above problems and by decomposing a raw material hydrocarbon into carbon, that is, carbon black and hydrogen, without producing carbon monoxide or carbon dioxide. A carbon black production method and production apparatus capable of producing carbon black with a high production yield and high purity and suppressing the production amount of a gaseous combustion product produced as a by-product to produce carbon black efficiently. To provide.

[0008]

A method for producing carbon black according to the present invention for solving the above-mentioned problems is a method of heating and vaporizing a liquid or solid hydrocarbon raw material at room temperature, and using the vaporized hydrocarbon raw material as a carrier gas. Along with this, it is structurally characterized in that it is introduced into an external heat type pyrolysis furnace held in an oxygen-free atmosphere and heated to a predetermined temperature for pyrolysis.

Further, the production apparatus is provided with a raw material vaporizer 6 for heating and vaporizing a liquid or solid hydrocarbon raw material at room temperature, and a raw material nozzle 12 for introducing the vaporized hydrocarbon raw material into a furnace together with a carrier gas. External pyrolysis furnace 13 for pyrolyzing hydrocarbon raw materials and cooling pipe for cooling pyrolysis gas
The constitutional feature is that it comprises 18 and a separator 19 for separating carbon black from the pyrolysis gas.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The raw material used in the present invention is a liquid or solid hydrocarbon at room temperature, and the hydrocarbon raw material is heated to a temperature above its boiling point to be vaporized and supplied to the pyrolysis furnace in a gaseous state. . The hydrocarbon raw material is preferably an aromatic one having a large conversion rate to carbon black, and more preferably a single substance for uniformly promoting the thermal decomposition reaction. Specifically, FCC residual oil (fluid catalytic cracking residual oil), coal-based heavy oil, or the like can be used by heating to a predetermined temperature to vaporize the volatile fraction, and more preferably benzene, naphthalene, A simple substance of aromatic hydrocarbon such as anthracene is used, and its purity is preferably 95% or more.

[0011] The vaporized hydrocarbon raw material is conveyed together with the carrier gas while being maintained at a predetermined temperature not lower than the boiling point, and is introduced into a pyrolysis furnace. As the carrier gas, an inert gas such as nitrogen, hydrogen or argon is preferable so as not to adversely affect the properties of carbon black produced by the thermal decomposition of hydrocarbons, and the gas is mixed with the vaporized hydrocarbon raw material at an appropriate ratio to generate heat. Supplied to the decomposition furnace.

As the thermal decomposition furnace, an external heat type thermal decomposition furnace of the type that is heated from the outside by electric heat or a combustion burner is used. The hydrocarbon raw material and carrier gas vaporized in the thermal decomposition furnace heated and maintained at a predetermined temperature Mixed gas is introduced. The hydrocarbon raw material is pyrolyzed into carbon black and hydrogen in the pyrolysis furnace, but in this case it is necessary not to cause an oxidative combustion reaction, and the atmosphere of the pyrolysis furnace is maintained in an oxygen-free atmosphere without oxygen To be done. The oxygen-free atmosphere refers to an atmosphere in which not only free oxygen but also an oxygen compound does not exist, and an oxygen-free atmosphere can be formed and maintained by an inert gas such as nitrogen, hydrogen, or argon used as a carrier gas.

The quality of the carbon black produced is determined by setting the ratio of the hydrocarbon source gas and the carrier gas to be introduced into the pyrolysis furnace, the flow rate of the gas to be introduced, the pyrolysis temperature, etc. It can be controlled by adjusting the gas flow rate, the residence time, the production concentration of carbon black, and the like.

The pyrolysis gas composed of carbon black produced by pyrolysis and hydrogen and a carrier gas can be used by circulating a mixed gas of hydrogen and a carrier gas as a carrier gas after separating and recovering carbon black. It can also be used as a fuel for an external heat type pyrolysis furnace or a raw material vaporizer.

FIG. 1 is an explanatory view exemplifying the configuration of an apparatus for producing carbon black according to the present invention. In FIG. 1, a raw material tank 1 contains a liquid or solid hydrocarbon raw material at room temperature. In the case of a solid raw material at room temperature, the raw material tank 1 is preheated to a temperature equal to or higher than the melting point by a preheating heater 2 to be in a liquid state. Stored in. The hydrocarbon raw material is supplied to the raw material vaporizer 6 from the hydrocarbon raw material feed pipe 5 while controlling the hydrocarbon raw material at a predetermined flow rate by the pump 3 and the flow controller 4. The raw material vaporizer 6 is provided with a raw material vaporization heater 7 for vaporizing a liquid hydrocarbon raw material. The raw material vaporizer 6 is heated at a predetermined temperature to vaporize the raw material at a predetermined speed, and a hydrocarbon raw material gas discharge pipe 8 is provided. Sent from.

A carrier gas such as nitrogen, hydrogen, or an inert gas is stored in a carrier gas tank 9 and is sent out while being controlled at a predetermined flow rate by a flow controller 10. The hydrocarbon raw material gas vaporized by the raw material vaporizer 6 is mixed with the carrier gas by flowing into a carrier gas flow pipe 11 shown in a partially enlarged view in FIG. Supplied. The mixed gas is heated from a raw material nozzle 12 to a predetermined temperature in a core tube of an external heat type pyrolysis furnace 13.
The hydrocarbon feed gas is thermally decomposed into carbon black and hydrogen. The thermal decomposition temperature varies depending on the hydrocarbon used as the raw material, but is preferably 1200 ° C. or higher.

The hydrocarbon raw material gas and the carrier gas can be mixed in the raw material vaporizer 6, and FIG.
An apparatus for mixing a hydrocarbon raw material gas and a carrier gas vaporized therein is illustrated in a partially enlarged view. In FIG. 3, a vaporized hydrocarbon raw material gas is mixed with a carrier gas fed at a predetermined flow rate from a carrier gas feed pipe 15, and the mixed gas is transported in the flow pipe and is then subjected to external thermal pyrolysis through a raw material nozzle 12. Furnace 13
And is thermally decomposed.

The external heating type pyrolysis furnace 13 is heated to a predetermined temperature by an appropriate heating device 16 such as an electric heating type or a combustion burner type. FIG. 1 shows a combustion burner type heating device.
A fuel such as propane is burned by the burner 17 to heat the external heat type pyrolysis furnace 13 to a predetermined temperature, for example, 1400 ° C., and the introduced hydrocarbon raw material gas is pyrolyzed into carbon black and hydrogen.

After the pyrolysis gas is cooled by a cooling pipe 18 provided at the outlet of the external heat type pyrolysis furnace 13, carbon black is separated and collected by a separator 19. As the cooling pipe 18, an external water-cooled type having a double pipe structure is used.
Promptly cool to a temperature below ℃. The separator 19 separates the carbon black in the pyrolysis gas, and an appropriate separator such as a filtration separation method using a filter cloth or a centrifugal separation method using a cyclone is used.The pyrolysis gas that separates the carbon black contains hydrogen. Since it is a flammable gas, it can be recovered and used as fuel for heating the external heat type pyrolysis furnace 13, and can be circulated and used as part of the carrier gas.

[0020]

EXAMPLES Examples of the present invention will be described in detail below in comparison with comparative examples.

Example 1 Carbon black was produced using benzene (purity 99%) as a hydrocarbon raw material by the production apparatus shown in FIG. Hydrocarbon feed pipe 5 to 10 containing benzene at a rate of 75 g / hr
The raw material vaporizer 6 adjusted to a temperature of 0 ° C. was fed to vaporize benzene. The raw material vaporizer 6 having the structure shown in FIG. 3 is used, and nitrogen gas preheated to a temperature of 100 ° C. is used as a carrier gas at a rate of 0.27 m ³ / hr from the carrier gas feed pipe 15 to the raw material vaporizer 6 Sent to. The vaporized mixed gas of benzene and nitrogen was introduced into the furnace core tube 14 of the external thermal pyrolysis furnace 13 from the raw material nozzle 12 while being kept at a temperature of 100 ° C. The external heat type pyrolysis furnace 13 is heated by a burner 17 while circulating nitrogen gas in the furnace core tube 14 in advance to obtain a temperature of 1400.
It was formed and maintained in an oxygen-free atmosphere at ℃, and benzene was thermally decomposed into carbon black and hydrogen gas. The pyrolysis gas was rapidly cooled to a temperature of 500 ° C. by an external water cooling type cooling pipe 18, and then a carbon black was separated and collected on the furnace cloth using a filtration tower as a separator 19. The filtered gas containing hydrogen gas after separating the carbon black is burner 17
It was circulated and used as fuel.

The characteristics of the carbon black thus obtained were measured and shown in Table 1 in comparison with the production conditions. In addition, TCD (thermal conductivity detector) or F
The pyrolysis gas composition was measured by gas chromatography equipped with an ID (flame ionization detector), the carbon black yield was calculated from the balance balance of the supplied carbon by the formula (1), and these results are also shown in Table 1. . Gas analysis yield (%) = [(carbon amount in introduced raw material)-(carbon amount in pyrolysis gas)] / [(carbon amount in introduced raw material)] × 100 (1)

Example 2 Using naphthalene (purity 99%) as a hydrocarbon raw material,
What was made into a liquid by heating and melting at 00 ° C. was fed at a rate of 75 g / hr into the raw material vaporizer 6 adjusted to a temperature of 250 ° C.,
Vaporized naphthalene. The same raw material vaporizer 6 as that used in Example 1 was used, and nitrogen gas was used as a carrier gas and the preheating temperature was set to 250 ° C., except that carbon black was obtained by thermal decomposition using the same method and conditions as in Example 1. Was manufactured. With respect to the obtained carbon black, the carbon black characteristics and the pyrolysis gas composition were measured by the same method as in Example 1, and the gas analysis yield was calculated. These results are also shown in Table 1 in comparison with the production conditions.

Example 3 Anthracene (purity 96%) was used as a hydrocarbon raw material, and 25
Anthracene was vaporized by feeding into a raw material vaporizer 6 adjusted to a temperature of 400 ° C. at a rate of 75 g / hr, which was heated and melted to a liquid state at a temperature of 0 ° C. The raw material vaporizer 6 is the first embodiment.
The same as the above, using nitrogen gas as a carrier gas,
Carbon black was produced by thermal decomposition according to the same method and conditions as in Example 1 except that the preheating temperature was set to 400 ° C.
The characteristics of carbon black and the composition of the pyrolysis gas were measured by the same method as above, and the gas analysis yield was calculated. These results are also shown in Table 1 in comparison with the production conditions.

Comparative Example 1 The same benzene as in Example 1 was used as a hydrocarbon raw material, and benzene was supplied at a rate of 75 g / hr from the hydrocarbon raw material feed pipes 5 to 10.
The raw material vaporizer 6 adjusted to a temperature of 0 ° C. was fed to vaporize benzene. The raw material vaporizer 6 having the structure shown in FIG. 3 is used, air is used instead of the nitrogen gas of Example 1 to preheat to a temperature of 100 ° C., and the air is 0.27 m ³ / hr.
Was fed to the raw material vaporizer 6. The mixed gas of vaporized benzene and air was adjusted to a temperature of 1400 ° C. from the raw material nozzle 12 while being maintained at a temperature of 100 ° C., and introduced into the furnace core tube 14 of the external heating type pyrolysis furnace 13. In the core tube 14, benzene was partially burned and the rest was decomposed into carbon black and hydrogen. The pyrolysis gas is rapidly cooled to a temperature of 500 ° C by an external water-cooled cooling pipe 18, and then separated by a separator 19
As a result, carbon black was separated and collected on the furnace cloth using a filtration tower. With respect to the carbon black thus obtained, the carbon black characteristics and the pyrolysis gas composition were measured by the same method as in Example 1, and the gas analysis yield was calculated. These results are also shown in Table 1 in comparison with the production conditions.

[0026]

[Table 1]

Examples 4 and 5 The FCC residual oil having the characteristics shown in Table 2 and the heavy coal-based oil were used as the hydrocarbon feedstock, and the feedstock vaporizer 6 shown in FIG.
It was delivered at the rate of g / hr. The temperature in the raw material vaporizer 6 was adjusted to 420 ° C., and the vaporized FCC residual oil was circulated through the carrier gas flow pipe 11 at a rate of 0.27 m ³ / h at a temperature of 450.
It was made to flow into nitrogen gas at 0 ° C. and mixed. Core tube 14 with this mixed gas kept at 1400 ° C in an oxygen-free atmosphere
It was introduced into and thermally decomposed. The carbon black was separated and recovered by the same method as in Example 1, and the carbon black characteristics and the pyrolysis gas composition of the obtained carbon black were measured by the same method as in Example 1 to calculate the gas analysis yield. These results are shown in Table 3 in comparison with the production conditions.

Comparative Examples 2 and 3 Carbon black was produced by the same method and conditions as those in Examples 4 and 5, except that air was used instead of nitrogen gas in Examples 4 and 5. The carbon black characteristics and the pyrolysis gas composition were measured by the same method as in 1, and the gas analysis yield was calculated. These results are also shown in Table 3 in comparison with the production conditions.

[0029]

[Table 2]

[0030]

[Table 3]

From the results shown in Tables 1 and 3, in the examples, since the hydrocarbon raw material is efficiently pyrolyzed into carbon black and hydrogen gas without burning, carbon monoxide and carbon dioxide are not generated. It can be seen that carbon black can be produced with a high production yield. In addition, carbon black having extremely low ash content can be obtained by using the vaporized raw material that has been fractionated.

[0032]

INDUSTRIAL APPLICABILITY As described above, according to the method and apparatus for producing carbon black of the present invention, a hydrocarbon raw material can be efficiently converted into carbon black and hydrogen without producing carbon monoxide, carbon dioxide, steam or the like. Since it can be pyrolyzed, high-purity carbon black can be produced with a high production yield. In addition, since the amount of pyrolysis gas produced is also reduced, it is possible to efficiently produce carbon black, and to produce carbon black without the emission of a large amount of harmful carbon dioxide for the protection of the global environment. Is extremely useful as the method and device.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating the configuration of a carbon black manufacturing apparatus according to the present invention.

FIG. 2 is a partially enlarged view illustrating a method of mixing a vaporized hydrocarbon raw material gas into a carrier gas.

FIG. 3 is a partially enlarged view illustrating another method of mixing a vaporized hydrocarbon raw material gas with a carrier gas.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Raw material tank 2 Preheating heater 3 Pump 4 Flow rate controller 5 Hydrocarbon raw material inlet pipe 6 Raw material vaporizer 7 Raw material vaporization heater 8 Hydrocarbon raw material gas discharge pipe 9 Carrier gas tank 10 Flow rate controller 11 Carrier gas flow pipe 12 Raw material Nozzle 13 External thermal pyrolysis furnace 14 Core tube 15 Carrier gas inlet tube 16 Heating device 17 Burner 18 Cooling tube 19 Separator

Claims (4)

[Claims] 1. A liquid or solid hydrocarbon raw material is heated and vaporized at room temperature, and the vaporized hydrocarbon raw material is introduced together with a carrier gas into an external heat type pyrolysis furnace maintained in an oxygen-free atmosphere and heated to a predetermined temperature. A method for producing carbon black, characterized in that it is thermally decomposed. 2. The method for producing carbon black according to claim 1, wherein the liquid or solid hydrocarbon raw material at room temperature is an aromatic hydrocarbon alone. 3. The method for producing carbon black according to claim 1, wherein the carrier gas is nitrogen, hydrogen, or an inert gas. 4. A raw material vaporizer 6 for heating and vaporizing a liquid or solid hydrocarbon raw material at room temperature, and a raw material nozzle 12 for introducing the vaporized hydrocarbon raw material into a furnace together with a carrier gas.
External heat type pyrolysis furnace 13 for pyrolyzing the introduced hydrocarbon raw material 13
An apparatus for producing carbon black, comprising: a cooling pipe 18 for cooling the pyrolysis gas; and a separator 19 for separating carbon black from the pyrolysis gas.