RU2164527C1 - Method of preparing raw material for producing industrial carbon - Google Patents

Abstract

FIELD: preparation of any grades of industrial carbon. SUBSTANCE: method comprises mixing component of petroleum or coal origin in hydrodynamic rotor and pulse activator at pulsation frequency of 600-2400 s^-1 for 2-90 s depending on viscosity of components being mixed which is 2-40 mm²/s at 100 C. EFFECT: method makes it possible to increase mixing efficiency and reduce energy consumption. 4 ex, 1 tbl

Description

 The invention relates to the field of preparation and use of liquid hydrocarbon raw materials for the production of carbon black and can be used for the preparation of raw materials for any grades of carbon black.

 Traditionally, several types of hydrocarbons are used in factories producing carbon black, including mixtures of petroleum and coal origin.

 Each of the components has its own physicochemical characteristics, depending on the methods of obtaining the feedstock, fractional and hydrocarbon composition of the final products.

 As the oil components, the products of thermal or thermocatalytic processing of oil distillates and / or residues are used - thermogas oil, thermal oil, thermal resin, coke distillates, cracked gas oils, pyrolysis resins, extracts for the selective purification of oils and / or gas oils, various technological mixtures.

 As coal and shale components, pitch distillates, anthracene, naphthalene oils or fractions, coal tar are applicable.

 In the present invention, any mixture of the above components in various compositions and ratios can be used.

 To obtain sustainable stable raw materials in order to ensure a normal technological regime and the production of carbon black of uniform quality, the plants pre-process the raw materials.

 One of the main stages of such processing is the mixing of various types of raw materials before feeding it to the production process.

 A known method of mixing several types of raw materials by pumping them into the tank in predetermined proportions, followed by circulation of the raw material by pumping it from the bottom of the tank to the top. To obtain a homogeneous mixture of various types of raw materials requires 24 hours [V.P. Zuev, V.V. Mikhailov. Soot production. Ed. 3rd break and add. Ed. "Chemistry", M., 1970, p. 64].

 A similar method is described for mixing for 18 hours thermogasoil with green oil in a ratio of 1: 1 [T.G. Gyulmsaryan, L.P. Gilyazetdinov. Raw materials for the production of carbon furnace soot. M., ed. "Chemistry", 1975, art. 133]. However, towards the end of the tests, although slightly, a weighting of the raw material mixture was observed from the top to the bottom of the tank. In addition, the known method is long and energy-intensive, since the mixing of raw materials takes about a day. Other well-known methods, such as the use of mechanical stirrers, diaphragm, injection mixers or compounding in the pipeline, including with the introduction of chemical additives, homogenizers, surfactants, they did not find wide distribution, since they did not lead to a noticeable increase in the homogeneity of the raw materials compositions. [Problems of obtaining and efficient use of raw materials for the production of carbon black. - Materials Vses. scientific and technical Sov., Omsk, September 18-19. 1990, p. 121]. The use of intracavity paddle mixers for homogenization of raw materials mixtures, which is proposed in the known method [ibid.], Intensifies the process of mixing raw materials, however, it relates more to the erosion and dispersion of sediments formed in raw tanks producing carbon black. In general, the proposed method is labor intensive since it involves several stages (selection of a dispersing agent and its ratio with the precipitate, sequential dispersion of the precipitate and its transfer to the production of carbon black) with the use of additional settlers and filters, which increases capital, operating and energy costs.

It is known to use ultrasound to increase the uniformity of raw material mixtures [Quality and effective use of hydrocarbon raw materials in the production of carbon black. Materials Vses. scientific and technical Sov., Omsk, March 13-15, 1984, p. 138]. However, it is unlikely that the method can be implemented in industry, since it is associated with very high energy costs (1 min of ultrasonic treatment per 100 ml of composition and an intensity of 30 W / cm ² , which is practically not feasible upon transition to industrial conditions).

 The closest in technical essence and the achieved effect to the proposed is a method in which to increase the efficiency of exposure to colloidal systems, incorporating various raw materials for the production of carbon black, use the cavitation treatment of mixed compositions. [Problems of obtaining and efficient use of raw materials for the production of carbon black. - Materials Vses. scientific and technical Sov., Omsk, September 18-19, 1990, p. 134].

The method is carried out on a laboratory cavitation installation of a closed type with a high-speed DC motor with a rotation frequency of 100 and 120 s ^-1 (6000 and 7200 rpm) and a stirrer with three blades. The treatment of the mixture, consisting of 80% coke-chemical feedstock and 20% cracked gas oil, was carried out at 20 ^° C for 2 minutes.

 As a result of cavitation treatment, the colloidal and rheological properties of the raw material for producing carbon black changed, an increase in the kinematic stability of the system was noted, however, specific data on its homogeneity and stability before and after processing were not provided.

In addition, the method has the following disadvantages:
- the frequency of processing due to the closed type of installation, which complicates its practical implementation on an industrial scale;
- to create a cavitating effect using an impeller with blades, it is necessary to apply high speeds of rotation of the shaft, which is associated with significant energy consumption;
- a closed system does not allow to increase the effectiveness of the cavitating effect, since the frequency of the pulsations of the liquid in the volume is insufficient to achieve a highly stable homogeneous system (300 and 360 s ^-1 ).

 In connection with the above disadvantages, the known method is ineffective when mixing components with different physicochemical characteristics, especially if they have significant differences in viscosities.

 The technical task of the invention is to increase the efficiency of mixing and reduce energy consumption.

The problem is solved in that in the method of preparing raw materials for carbon black, including mixing components of oil and / or coal origin before the process of producing carbon black, the mixing is carried out in a hydrodynamic rotary pulsation activator with a pulsation frequency (600-2400) s ^-1 depending from a viscosity of the mixed components of 2-40 mm ² / s at 100 ^o C for 2-90 s.

A distinctive feature of the invention is the implementation of the process in a rotary pulsation activator (RPA) with a pulsation frequency (600-2400) s ^-1 for 2-90 s, depending on the viscosity of the mixed components, 2-40 mm ² / s.

 A new technique for mixing raw materials for the production of carbon black in RPA led to a positive result, which is that, 6 with a simultaneous increase in the frequency of pulsations in the volume of liquid, the rotor speed decreased. This is achieved by the fact that passing through a series of holes of a special design in the rotor blades and the stator housing creates an additional shock increase in the velocities of the mixed liquids in a high-frequency pulsating cavitation mode.

At a frequency of rotation of the rotor is 2-5 times less compared to the known method (25; 50 s ^-1 vs. 100; 120 s ^-1 ), the ripple frequency increased by 1.6-8 times (600-2400 against 300; 3660 s ^{- 1} ). In this regard, the efficiency of mixing of the components is significantly increased while reducing energy consumption.

The established limits for changing the value of the pulsation frequency of 600-2400 s ^-1 and the processing time of 2-90 s create an intense cavitation field with a maximum effect on the mixed composition, which allows one to obtain a stable, homogeneous and highly dispersed system for components that differ sharply in viscosities (2-40 mm ² / s at 100 ^o C).

 The proposed method is illustrated by specific examples.

Example 1
A mixture of raw materials, consisting of anthracene oil with a kinematic viscosity of 2.03 mm ² / s at 100 ^o C and a cracking residue of thermal cracking of flavored petroleum products with a viscosity of 22.51 mm ^{2, is} fed into the rotor-pulsation activator (RPA) case through the inlet pipe / s at 100 ^o C in a mass ratio of 60:40.

The mixture enters between the surfaces of the rotor blades, the rotation speed of which is 25 s ^-1 (1500 rpm), and the stator, passes with high pressure and speed through the stator holes (24 pcs.), Which creates a pulsation frequency of 600 s ^-1 , and after 2 s, the mixture exits the casing at the outlet pipe into the feed tank. The kinematic viscosity of the mixture at the outlet is 13.85 mm ² / s at 100 ^o C. Next, the change in viscosity over time is recorded by sampling from the top and bottom of the tank after 3 hours, 3 days and 15 days. The change in viscosity along the height of the tank is calculated relative to the viscosity of the mixture at the outlet of the RPA, which in this example is 0.07 rel. % after 15 days.

 Examples 2, 3 are carried out analogously to example 1, but take a mixture of anthracene oil with other petroleum components that differ in their method of production and physico-chemical properties, and in other ratios indicated in the table. It also contains data on the processing mode of the mixed composition, the viscosity of the homogenized mixture — the raw material for carbon black at the outlet of the RPA, and the stability characteristics of the resulting mixture (viscosity change along the height of the tank).

 Example 4 is carried out similarly to the known method on the same starting components - coke-chemical (anthracene oil) 80% and petroleum (cracking gas oil) 20%, since the known method does not quantify the stability of the target product - raw materials for the production of carbon black. For processing using a similar laboratory mixer of the closed type. The mixing conditions in example 4 are the same as the known ones and are shown in the table, where the results are also presented.

The table shows that in the proposed method, in comparison with the known method, mixing efficiency is significantly increased due to the creation of a high-frequency pulsating mode with a pulsation frequency of 600-2400 s ^-1 , and a wide range of pulsation frequency changes allows you to adjust the processing mode of the mixed composition depending on the viscosity of the original components. At the same time, stable, highly dispersed homogeneous mixtures were obtained that did not exfoliate for 15 days. Even for sharply different components of the raw mix (in example 2, three components are mixed with a maximum viscosity difference of 2 to 40 mm ² / s).

 The relative change in the stability of the system according to the proposed method is at most 3.4%; in the known method 32.4%.

Another advantage of the new technical solution for the proposed method is to reduce energy costs. To achieve homogenization of the mixture in a known method using a high speed of rotation of the shaft (7200 rpm; processing time 2 min - example 4); while the cavitating effect is expressed by a pulsation frequency of 360 s ^-1 . In the proposed method, a similar raw material composition (example 3) is processed for 30 s with a rotor speed of 3000 rpm with a pulsation frequency of 1200 s ^-1 , and therefore energy consumption is sharply reduced (9.6 times).

 Thus, the proposed combination of distinctive features ensures the achievement of the goal, which consists in increasing the efficiency of mixing and reducing energy consumption.

Claims (1)

A method of preparing raw materials for the production of carbon black, comprising mixing components of oil and / or coal origin before the process of producing carbon black, characterized in that the mixing is carried out in a hydrodynamic rotary-pulsation activator with a pulsation frequency of 600 - 2400 s ^-1 for 2 - 90 s depending on the viscosity of the mixed components, component 2 - 40 mm ² / s at 100 ^o C.

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