JPS6220227B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an apparatus for producing carbon black that is effective for increasing and controlling primary structure. The primary structure of carbon black is a non-destructive aggregate structure evaluated by compressed DBP oil absorption (ASTM, 24M4DBP).
In particular, for rubber reinforcement purposes, an increase in the amount and appropriate control are required. Conventionally, as a means to increase or control structure in terms of production process equipment, for example, a method of introducing main feedstock oil and auxiliary feedstock oil in multiple stages into the reaction zone of a normal single-head cylindrical furnace, or a method using a bench lily throat reaction. Methods such as varying the raw material supply position by expanding and contracting a raw material oil injection nozzle inserted into the head of the furnace are known, but these methods cannot be expected to control a large increase in primary structure. Have difficulty. In other words, the formation of primary structures occurs when highly viscous minute oil droplets (intermediate products that become carbon black precursors) produced through thermal decomposition and polycondensation of raw material hydrocarbons repeatedly collide with each other and fuse together. This is thought to be due to agglomeration, which is then converted into an integral agglomerated form through the next carbonization stage. Therefore, in order to effectively increase and control this, it is necessary to increase the concentration of carbon black intermediate products in the pyrolysis gas stream as much as possible, and to maintain the speed and frequency of mutual collisions at a high level. Adjustment is the basic condition. However, the conventional production means using a single-head furnace naturally has a limit to the degree to which the above conditions can be applied, and in particular, in the production system of hard carbon black where the concentration of intermediate products in the pyrolysis gas is low, the primary structure It is extremely difficult to achieve a large-scale increasing effect. The inventors previously proposed a manufacturing device for efficiently increasing and controlling the primary structure by colliding carbon black intermediate products in a pyrolysis gas stream with each other at high speed and high density (Unexamined Japanese Patent Publication No. Showa 59-
49267), but the present invention adds further structural improvements to this structure. The invention will now be explained on the basis of exemplary embodiment drawings. FIG. 1 is a longitudinal sectional front view showing the entire carbon black manufacturing apparatus, which is usually constructed from a refractory material and a steel shell. In the figure, 1 and 1' are generation parts, and 2 is a cylindrical main reaction zone in which a quenching spray nozzle 3 is provided in the downstream region. The generating parts 1, 1' are
A combustion chamber 7 equipped with a combustion air tangential introduction pipe 4, an axial combustion burner 5, and a feedstock oil injection nozzle 6 at the head, and a small-diameter pyrolysis conduit 8 continuous with the combustion chamber 7.
It has an independent generation mechanism consisting of
Installed in multiple series of two or more at the head of the furnace. The tip of each pyrolysis conduit 8 is convergently joined to the upstream end of the main reaction zone 2 and joined together. This connection is set so that the intersection angle α formed by the axis of each pyrolysis conduit and its intersection point P is less than 180°, preferably within the range of 90° to 30°. Reference numeral 9 denotes a base aperture device interposed at the convergence meeting site. The base expansion device 9 has a mechanism that expands and contracts in the axial direction of the cylindrical main reaction zone 2 to enlarge and reduce the passage of each pyrolysis conduit 8, and as illustrated in FIG. It consists of a fireproof member 10 with a sharp tip that slides through a hole, and a suitable mechanical device 11 that expands and contracts this by screwing or the like. The cylindrical main reaction zone 2 may be formed to have the same inner diameter over its entire length, but as shown in FIG.
Furthermore, it is effective to provide a bench lily-shaped throat portion 14 at the entrance portion of the narrow diameter portion 12. Since the carbon black manufacturing apparatus according to the present invention has the above-mentioned structural mechanism, it is possible to effectively control the increase in primary structure through the following production steps. First, the feedstock oil injected in individual generation parts undergoes thermal decomposition by high-temperature combustion gas and dehydrogenation polycondensation, and becomes fine grain nuclei of high viscosity oil droplets, which become carbon black intermediate gas streams suspended in the reaction gas. Transform. A plurality of carbon black intermediate product gas streams generated in different series are accelerated in the process of passing through each pyrolysis conduit 8, reach point P, and collide continuously, but the degree of collision speed is determined by the base throttle device 9. It can be freely strengthened or controlled by expanding and contracting. At this time, P
Since the point zone forms a state in which the reactant gas flows individually generated in multiple series are aggregated, the density of the carbon black intermediate product present therein is significantly higher than in the case of a conventional single-head generation system. For this reason,
The frequency of collision and contact of the fine nuclei of high viscosity oil droplets constituting the carbon black intermediate product is significantly increased, and this, together with the high-speed collision effect of the base aperture device, effectively forms the primary structure. increase It is effective to cause the carbon black intermediate gas flows to collide with each other at an angle of intersection α in the range of 90° to 30°, but if a bench lily-shaped throat portion 14 is further provided at the entrance of the narrow diameter portion 12, collisions will occur. The gas flow is compressed within the defined narrow area to form a more dense turbulent state, which is promoted by the degree of increase in the primary structure. As described above, according to the carbon black manufacturing apparatus of the present invention, it is possible to impart a primary structure that is highly or controlled to a high standard due to its unique structure and generation mechanism, and is therefore suitable for manufacturing carbon black for rubber reinforcement. Extremely useful. Example Narrow diameter part 12 with inner diameter 90mm and length 800mm and inner diameter 200
The front surface of the cylindrical main reaction zone 2 has a wide diameter section 13 with a length of 3,000 mm, a tangential direction introduction pipe 4 for combustion air, an axial combustion burner 5, and a raw material oil injection nozzle 6 at the head. Inner diameter 400mm with length
Two series of generation parts 1 and 1' having a combustion chamber 7 of 800 mm (including a conical portion of 200 mm) and a pyrolysis conduit 8 with an inner diameter of 60 mm and a length of 600 mm connected thereto are converged at an intersection angle of α60°. Illustrated structure that binds and stretches in the axial direction of the main reaction zone at the convergent association site (Figure 2)
A base aperture device 9 was installed. The feedstock oil injection nozzle 6 of each generation part was fixed so that the tip portion was located 70 mm upstream from the entrance of the pyrolysis conduit 8. Using the device with the above structure, change the aperture ratio using the base aperture device 9 to obtain SAF (N-110) and IISAF.
(N-285) class hard carbon black was manufactured. An aromatic hydrocarbon having the characteristics shown in the table was used as the raw material oil.

【table】

[Table] The table shows a comparison of the manufacturing conditions applied and the characteristics of the carbon black produced. The manufacturing conditions in the table are for a single generation part of each series, and the reduction ratio is shown as a ratio to the cross section of each pyrolysis conduit.

[Table] The structure characteristics of the conventional single-head furnace type device are DBP oil absorption of 111 for the SAF (N-110) type.
~115c.c./100g, compression DBP oil absorption is 97~99
cc/100g, and IISAF-Hs (N-285)
At the DBP oil absorption level of 123 to 127 c.c./100g, the compressed DBP oil absorption amount is approximately 100 to 103 c.c./100g. Therefore, the results shown in the table indicate that the primary structure (compression DBP oil absorption) can be effectively increased overall compared to the conventional equipment, and that the degree of increase can be effectively controlled according to the drawing ratio. It shows.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view showing one embodiment of a carbon black manufacturing apparatus according to the present invention, and FIG. 2 is an enlarged sectional view of the convergence and meeting portion of FIG. 1. 1, 1'... Generation part, 2... Main reaction zone, 3
... Quenching spray nozzle, 4 ... Cutting line direction introduction pipe, 5 ... Combustion burner, 6 ... Raw material oil injection nozzle, 7 ... Combustion chamber, 8 ... Pyrolysis conduit, 9 ...
... Base throttle device, 10 ... Fireproof member, 11 ... Telescopic mechanical device, 12 ... Narrow diameter part, 13 ... Wide diameter part, 14 ... Throat part, P ... Intersection, α ... Intersection angle.

Claims (1)

[Scope of Claims] 1 A plurality of generating sections each consisting of a combustion chamber equipped with a combustion burner and a feedstock oil injection nozzle at the head and a pyrolysis conduit following the combustion chamber are provided in series, and the pyrolysis conduit of each generation section is In an apparatus having a structure in which the tip of the pyrolysis conduit converges with a cylindrical main reaction zone, the passage of each pyrolysis conduit is expanded or contracted at the convergence site of the pyrolysis conduit in a coaxial direction with the cylindrical main reaction zone. A carbon black manufacturing device that includes a diaphragm device at the base of the mechanism. 2. The carbon black manufacturing apparatus according to claim 1, wherein the cylindrical main reaction zone is formed by coaxially connecting a narrow diameter part and a wide diameter part having a bench lily-shaped throat at the inlet part.