DE2015914A1 - Process and device for the production of carbon black - Google Patents

Description

PrtTENiANWÄLTE 2 O 1 R 9 1 Δ

* \ DR.-ING. BY KREISLER DR.-ING. SCHÖNWALD DR.-ING. TH. MEYER DR. FUES DIPL ..- CHEM. ALEK VON KREiSLER DIPL.-CHEM. CAROLA KELLER DR-ING. KLUPSGH

COLOGNE 1, DElCHMANNHAUS

Cologne, April 1st, 1970 Kl / Ax

CABOT CORPORATION,

125 High Street, Boston, Massachusetts QgIlO (V.St.A.) .

Process and device for the production of carbon black

The invention relates to the production of carbon blacks by Decomposition of Liquid Hydrocarbons, Specifically an Improved Process for Conversion of liquid hydrocarbons into high quality carbon blacks in excellent yields and at unusually high yields Throughputs without the need for prior evaporation of the liquid feedstocks.

The invention lies within the general scope of the so-called continuous furnace process for the production of Soot. In particular, the invention has the task of the real benefits that come with these ver ~ drive by using very oxygen-rich. oxidizing gases in the generation of the heat for the decomposition of the liquid hydrocarbons used are achievable, to be maximally designed.

Some of the potential advantages of using oxygen-rich oxidizing gases in the furnace process to produce soot (e.g. eliminating the high content of inert substances, e.g. N ₀ , which are normally present in the system when air is used as the oxidizing agent) are already there been recognized

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however, large-scale applications in this field have not been realized as a result of practical difficulties in handling oxygen-rich systems. For example, US Pat. No. 2,623,811 deals with the possibility of using an oxygen-rich oxidizing gas in place of air in the furnace process, but the conclusion here is that the nitrogen thus eliminated is largely due to others ". "Heat absorbing gases", for example CO ₂ , CO, Hp or water vapor, which are introduced into the combustion zone with the oxygen-rich oxidant, must be replaced.

Accordingly, the main object of the invention is a practical process for the continuous production of carbon black under Use of an oxygen-rich oxidizing gas to generate heat and release energy for the more efficient conversion of liquid hydrocarbons into high quality carbon blacks. The procedure according to the Invention enables the production of high quality carbon blacks in excellent yields from any liquid Hydrocarbons without prior evaporation of these hydrocarbons, with unusually high levels P throughputs in production plants of a given size. The yields with a given liquid feed and / or production speeds with plants of a given size so 'much higher that the higher cost of the oxygen-rich oxidizing agent used in comparison to more than offset the cost of using air.

The invention further comprises devices which are suitable for carrying out the method according to the invention on an industrial scale and which are compact and economical in construction and maintenance, safe in operation and over a wide range of working conditions

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are easy to control.

The invention also enables the range of starting liquid materials to be evaluated Hydrocarbons that are "at a continuous Furnace processes can be converted into high quality carbon blacks, and / or expanding the range of excellent Carbon black products made with the help of a furnace process can be produced.

The invention also includes entirely new carbon black products that were previously unknown and have not been described.

The method according to the invention consists of the following Result of measure η: l) One burns continuously a suitable liquid or gaseous fuel. substance with an oxygen-rich oxidizing agent in a combustion zone maintained at a high temperature at a pressure of more than 0.21 atmospheres and leads from the end of the combustion zone located at the bottom in the direction of flow continuously the gaseous combustion products at high temperature as compacted, accelerating current, which is essentially moved in one direction as a closed column.

2) At a point where this stream has a kinetic

2 has energy that corresponds to a pressure of at least 0.21 kg / cm ', a large number of small, continuous, penetrating jets of a liquid hydrocarbon serving as a starting material are injected into this stream from its circumference in such an amount, that the total amount of liquid feed, which is adjusted to the temperature, the mass flow rate and the composition of the feed stream, is sufficient to ensure a temperature of at least 2200 ^° C. and conditions suitable for carbon formation. 3) The reaction mixture formed is quenched at a point which, in flow

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seen in the direction, is far enough down to allow the formation of carbon particles.

. The three stages of the process according to the invention are described in more detail below.

In the combustion stage, "the oxygen-rich oxidizing gas should consist primarily of molecular oxygen. Preferably it contains at least about 90 vol. $ O _2. The production of such concentrated forms of Op is generally not a problem as tech-

P nical oxygen gas of this purity is common today is available and the purity is typically above about $ 95 volume. However, it is possible to use mixtures of Oxygen with air, nitrogen and / or other common gases at an oxygen content down to only 50 vol. $ O2 or even less with considerable benefit as an oxygen-rich oxidizing gas in the method according to the invention for most fuels and to use liquid feedstocks. Regardless on the Op concentration in the oxidizing gas should be the Combustion conditions and / or the total proportions of combustible reactants are set in such a way that

fc that it is ensured that temperatures of at least about 2200 ^° C. are reached either before or after the injection of the liquid feedstock. As a gaseous fuel or .flüssiger all highly flammable gas, vapor or liquid fuels, for example, _o H _2, CO, CH _4, acetylene, alcohols, and kerosene are suitable. In general, however, fuels with a high content of carbon-containing components, in particular hydrocarbons, are preferred. For example, methane-rich fuels, such as natural gas and modified or enriched natural gas, as well as other hydrocarbon-rich streams, such as the various petroleum gases and liquids and by-products of refineries including C ₂ to C ₄ or Cc fractions, are heating oils

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etc., excellent fuels. In general, the heavier and more viscous tars and residual oils should. concentrated only in conjunction ^mi ^ or relatively pure oxygen streams are used to a violent and quick response in the "held at a high temperature combustion zone to ensure" In the "particularly preferred embodiment of the method according to the invention, a very high amount of heat, Z ₀ B 267 χ 10 kcal / hour / m, free in the combustion chamber.

Extremely important in the combustion stage of the process according to the invention is also the pressure under which the Combustion reaction is carried out. This pressure has been found to be between about 0.25 and 5.3 atmospheres must in order to maintain stable, high intensity combustion conditions and the formation of a stream of gaseous combustion products that have enough energy to use as a feedstock serving liquid hydrocarbon effectively in soot convert within a desired range of adjustable properties. Preferably the combustion pressure should be between about 0.35 and 3.5 atmospheres. For most desirable carbon blacks, a pressure is between about 0.7 and 2.1 atm generally the optimum.

The temperatures which occur in the process according to the invention are generally higher than in conventional carbon black production processes. A temperature of at least approximately 2200 ^° C. is always reached at some point in the process. Generally this is the case during incineration. If a very oxygen-rich mixture of oxidizer and fuel is used in the combustion stage, however, the maximum temperature can occur after the feedstock liquid hydrocarbon is introduced and in part with the unused hydrogen present in the hot gaseous products of combustion,

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responded. Accordingly, the fuel to oxidant ratio on the fuel-rich side should be limited to values at which adiabatic flame temperatures of at least about 220O ⁰ C are achieved, but at the other end of the scale oxygen / fuel ratios that are so high can be used that adiabatic flame temperatures occur which are below 2200 ^° C., but close enough to this value that this temperature is reached quickly when the liquid hydrocarbon used as starting material reacts with the oxygen in the hot gas stream of the combustion products.

The single most important feature of the invention is the manner in which the starting material is used liquid hydrocarbon in the above-explained stage (2) in those coming from the combustion stage (1) Stream of hot combustion gases is introduced. It has been found that any liquid hydrocarbon can be quickly converted to high quality carbon black at unusually high throughputs, if it is essentially across the circumference of this combustion gas flow after this flow has a back pressure of at least

0.21 kg / cm, injected in the form of a multitude of small, continuous jets of liquid which selectively penetrate the inner regions of the combustion gas flow, this is achieved by adding "the 'number, size and initial speed (or the injection pressure) of the liquid jets can be adjusted so that each jet penetrates well into the interior of the Combustion gas flow penetrates, but without penetrating to the opposite side of this flow. To the For best results, these liquid jets should be formed by the liquid starting material through free openings that have a diameter between approximately 0.25 and 1.5 mm, preferably less

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than about 1 mm, under a uniform pressure which is at least -7 kg / cm above the static pressure in the combustion gas flow. In general, the pressure under which the liquid starting material is injected under otherwise identical conditions, the higher the smaller the size of the opening. nungen is. The best combination of aperture diameter and injection pressure difference of course depends on the exact working conditions, including such important factors such as size and width of the stream of hot combustion gases and his ^one back pressure at the injection point of the liquid feed and the viscosity, the average molecular weight and other properties of the liquid Input material itself.

After the orifice size and the injection differential pressure have been determined, the number of orifices required can be easily determined as this is directly dependent on the amount in which the feed material must be added. In making the given type of carbon black with a given feedstock, this feedstock feed rate in turn depends largely on the amount of available heat and unused oxygen (if any) in the stream of hot combustion gases. For most types of soot, which are mainly of interest, the amount of feedstock added in connection with the amounts of oxygen and fuel supplied is set in such a way that the total combustion for the process (assuming a theoretically complete oxidation of all components to CO ₂ , H ₂ O, etc.) is between about $ 20 and $ 40. In principle, however, the process according to the invention can still advantageously be carried out with combustion values down to about 10 $ or up to about 50 $ with the formation of useful types of soot, using suitable reactants.

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For the third stage of the process described above, the most important parameters are the size and shape of the reaction space which is present between the injection of the liquid hydrocarbon serving as starting material and the cooling or quenching of the reaction mixture formed. To the reaction mixture, determined at a given volumetric flow rate of the total volume of the space between the injection zone of the liquid feed and the cooling zone, the V _erwe ii _ze i-fc in the main reaction zone in which

fe the carbon formation takes place. If from the combustion stage up to the injection stage of the starting material if the conditions described above are adhered to, the inventive method is capable High-performance process high-quality carbon blacks with unusually short dwell times, e.g. down to about 1 millisecond or even less, to produce. For most types of carbon black, the residence times are under optimal conditions usually in the range of about 5 to 100 milliseconds. Of course, you can often, if desired, with longer residence times of up to about 500 milliseconds or even more without any significant economic disadvantage

fe to be worked. At times this can come in handy prove to achieve certain special product properties. For more details on size and The shape of the reaction space and the type of cooling of the reaction mixture are discussed in more detail below.

Some preferred embodiments of devices are shown in the figures. For better understanding According to the invention, the process steps are explained in more detail below with reference to these embodiments described.

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Fig.1 is a longitudinal section through a device which to carry out the first stage (combustion) and the second stage (injection of the starting liquid hydrocarbon) of the process according to the invention «

Figure 2 is a cross section taken along line 2-2 of Figure 1. Figure 3 is a cross-section taken along line 3-3 of Figure 1.

Fig.4 is a longitudinal section through a device which to be connected to the outlet end of the in Fig.1 shown device is suitable to the emerging therefrom Take up the reaction mixture and use it after the expiry a suitable residence time for carbon formation to cool.

Fig.5 is a longitudinal section through a device which is generally similar to that shown in Figure 1, apart from the manner in which the liquid or gaseous fuel and the oxidizing gas are introduced ...

The device 10 shown in FIGS. 1, 2 and 3 for carrying out the combustion and for injecting liquid hydrocarbon in the context of the method comprises two coaxial, elongated outer sheaths 12 and 14 extending essentially over the same length. The inner sheath 12 encloses the Combustion chamber .16 and, together with the outer frame 14, forms a narrow annular channel 18 through which a liquid coolant, for example water, can be circulated with the aid of the inlet and outlet lines 20 and 22. A fuel with a high calorific value, for example a gaseous or liquid hydrocarbon, is fed through the feed line 24 to the antechamber 26 at the inlet end of the device 10 _. the combustion chamber \ ξ, elnge

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leads. Is In the particular ^A usführungsform, as best seen in Pig.2, a central opening 30, together with six provided approximately at the same distance in the circle arranged surrounding openings 30th Any other uniform geometric arrangements of the openings 30 are possible, but preferably at least five such openings are provided. At the very high input quantities and throughputs which are possible in the process according to the invention, about 13 to 15 such openings 30 are usually sufficient even for production on an industrial scale.

Slightly below (seen in the direction of flow) the fuel distributor plate 28 the oxygen-rich oxidizing agent is introduced laterally through line 32, which extends tangentially into the combustion chamber 16 on its circumference, which is formed by the inner wall of the shell 12 will open. The resulting rapid whirling or rotating movement caused by blowing in the oxidizing gas is produced at high speed in this way, causes excellent mixing of the oxidizing gas with the fuel jets entering through the openings 30 and ensures a fast, stable, very intensive combustion in room 16. Through the very oxygen-rich oxidizing agent used, the well-filled combustion chamber and the intense combustion achieved in it will normally release heat achieved more than 267 x 10 kcal / hour / m,

8 "5

and amounts of heat of more than 8.9 χ 10 kcal / hour / m are over a significant range of oxygen / fuel ratios on either side of stoichiometry, not uncommon, especially with the purer forms of oxygen and high calorific value fuels.

¹ In order to contain the hot combustion gases and to tame and utilize their heating capacity, insulation of the inner jacket 12. is not attempted. The coat

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12 and 14 are rather made of materials with high thermal conductivity, ζ.B; Metals such as aluminum, and a coolant such as water is circulated through the channel 18 at high speed. This will make that very costly problem associated with trying to find refractory insulation that would match the high Withstand temperatures and the thermal shock that occurs could, turned off. .

The pressure reached in the combustion chamber 16 is extremely important factor in ensuring successful

Carry out the rest of the procedure. So a »= ■ f

Minimum combustion pressure of about 1.27 kg / cm is required to produce a strong, steady flow of combustion gas which is properly directed into the next stage of the process, in which the liquid hydrocarbon serving as the feedstock is introduced. The pressure in the combustion chamber is preferably kept between about 1.4 and 3.5 kg / cm, since this not only creates a sufficiently strong and steady flow of hot combustion gases, but also absolutely stable combustion over a wide range of conditions, for example over a wider range of oxygen / fuel ratios. Even when used in its purer forms, the amount of oxygen supplied can vary between about $ 50 and 50056 of the amount _{theoretically required for complete combustion of the fuel to COp, H 9} O, etc. Shares from about $ 70 to $ 350 are preferred. Likewise, although the pressure in the combustion chamber can be increased up to about 6 ata, the combined combination of the other factors is seldom so unfavorable that combustion pressures of more than about 2 or 3 ata are required.

After the powerful flow of combustion gas is formed has, is at a point where this is essentially

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The closed column moving stream has reached a dynamic pressure of at least 0.21 kg / cm, the liquid hydrocarbon serving as starting material being injected transversely into this stream through a series of 4 small free openings 34 which lead through the inner jacket 12. The liquid hydrocarbon is supplied to these orifices at a substantially constant pressure through supply lines 36 or other suitable supply manifolds. Almost any acceptable speed ^VO is not less than 2 is suitable, provided that the liquid starting material these openings is supplied at a substantially uniform pressure, the ^v of the hot, depending on the nature of the starting material and the size erbrennungsgasstromes set of openings 34 so is that the liquid starting material penetrates into the interior of the combustion gas flow, but does not penetrate to the opposite side of this flow. As previously mentioned, these openings can be almost any diameter between about 0.25 and 1.5 mm as required. For most liquid starting materials, openings between 0.51 and about 0.5 millimeters are most suitable. The total number of openings 34 of a given size depends, of course, on the total amount of liquid starting material supplied and handled, which in turn depends on the nature of the hot combustion gas stream and the percentage of total combustion that is to take place in the entire process, etc., as already above explained.

This method of injecting the raw material liquid hydrocarbon as a plurality of small, transversely directed, contiguous, penetrating rays ensures uniform, rapid and finely dispersing and distributing the raw material throughout the stream of hot combustion gases, so

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that the starting material decomposes quickly and completely and in high quality carbon black in surprisingly high yields can be converted. Although compared to the usual atomization methods that are normally used when it is introduced of liquid hydrocarbons applied in carbon formation processes superior results will be achieved by using this injection method when the Back pressure of the hot combustion gas stream at the injection point is at least about 0.21 kg / cm the kinetic pressure or back pressure at this point to achieve optimal results, especially with the Production of carbon blacks with finer particles, preferably

■ 2

wise at least about 0.35 kg / cm. Overall lies the optimal back pressure at this point in general

2 between about 0.35 and 1.4 kg / cm.

The reaction mixture which has been formed in this way in the _{device 10 shown in Eig o} 1, 2 and 3 contains all of the heat and all of the carbon for soot formation, so that now only the necessary reaction time has to be set. This can easily be done by guiding the reaction device from the outflow end of the device into a suitable reaction space. For example, as shown in Figure 4, an open ended container 40 can be attached to the discharge end of the device 10 by means of mating flanges 38 and 42 which are provided with suitable circularly arranged bolt holes 44 and 44 '. The reaction space 46 in the container AO must be continuously free and open and usually have a larger cross-sectional area than the outflow end of the device 10. Preferably, the cross-sectional area of the inlet end of the reaction space 46 is several times greater than the cross-sectional area of the outlet -Römenäesäer device 10. The length of the reaction space 46 depends on the maximum

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Residence time from the for the carbon formation in large-scale Operation must be provided. The exact residence time for each case depends of course on the particular one The reaction conditions and the desired properties of the carbon black formed, however, it depends Methods according to the invention usually range from about 1 to 100 milliseconds for most types of soot of greater interest.

In order to create the possibility of ending the carbon formation reaction at the desired moment and thereby regulating the residence time, liquid atomization nozzles are provided at suitable points in the reaction space. For example, two such atomizing nozzles 48 are shown in FIG. In operation, the liquid to be atomized, usually water, is supplied to the nozzles 48 under a suitable pressure by means of lines 50. More than one group of atomizing nozzles can be provided to provide greater flexibility in changing the residence time for a given throughput or in changing the throughput for a given residence time. For example, additional nozzles 48 could be arranged at other locations, for example at locations A and / or B, which are indicated by the arrows in FIG. Since the carbon formation reaction is essentially terminated by the cooling, the mixture leaving the reaction space 46 through the outlet 52 consists of a hot aerosol or soot product in by-product gases. After exiting the outlet 52, this hot aerosol is subjected to the usual final treatments, ie cooling, separation and deposition of the solid particles, as is customary in the production of carbon black by the furnace process.

The container 40 could be hergegtellt of refractory material, as usual with most carbon black furnaces

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is, however will, it preferably-as well as the assembly 10 made of materials with high thermal conductivity, e.g. metals, and provided with a cooling jacket 54, as shown in Fig.4, so that during operation a suitable liquid coolant such as water with the aid of the inlet and outlet openings 56 and 58 can be circulated in it.

FIG. 5 shows an apparatus 60 which is generally analogous to the apparatus 10 shown in FIG. 1 and which can be used in place of the latter in order to carry out the first "two stages of the method according to the invention. The apparatus 60 thus comprises two The inner jacket 62 encloses the combustion chamber 66 and, together with the outer jacket 64, forms a narrow annular channel 68 for the circulation of a liquid coolant between the inlet 20 and the outlet 22 .

As with the device 10, the outflow end of the device .60 is circular with a splash 38 arranged bolt holes 44 provided. Likewise is the. Device 60 immediately before its outflow end with |

Means for injecting the liquid hydrocarbon used as starting material, namely small openings 34, to which the liquid hydrocarbon is fed through the lines 36, are provided. ■ -

The main difference between the apparatus shown in Fig.! Illustrated 10 and the device 60 illustrated in Figure 5 is thus in the manner of the introduction and mixing of the liquid or gaseous fuel with the oxygen rich oxidizing gas to trigger the running of high intensity combustion stage of the process. In the device 60, the oxygen

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rich gaseous oxidant through a series of openings 70 which open directly onto a common central Point in the inflow end of the combustion chamber 36 are directed laterally into the combustion chamber 66.

The oxidizing gas is the openings 70 under a suitable pressure with the aid of the supply lines 72 or supplied with the help of another suitable distributor. The liquid or gaseous fuel is using small bores 74, which are located at a point immediately in front of the point at which the bores 70 are in the combustion chamber 66 open, fork with the bores 70 and connect, blown into the oxidizing gas. The liquid one or gaseous fuel is supplied to the bores 74 through supply lines 76 or other suitable manifolds fed. In other words, the arrangement for blowing in or injecting fuel and oxidizing agent in the case of the device 60 shown in Figure 5, a beam-stabilized fire is generated in the combustion zone 66, while the device 10 shown in Figure 1 to a swirl-stabilized fire in the combustion zone 16 leads.

Some preferred embodiments of the invention, their advantages and flexibility, and in some cases the The following examples illustrate the consequences of working outside the prescribed limits.

example 1

The apparatus shown in Figures 1, 2, 3 and 4 was used. This device had the following essentials Dimensions:

Inner diameter of the jacket 12 19.05 mm

Length of the jacket 12 (measured from the distributor plate 28) 177.8 mm

Length of the jacket 12 (measured from

tangential entry 32) 152.4 mm

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Diameter of the openings 30 1.59 mm

(7 openings are provided, namely one in the middle and 6 equally spaced around the central opening in a circle of 12.7 mm). , ". ■

Diameter of the holes 34 0.5 ^ 1 mm

(Two opposing holes 34 are provided, which are spaced apart of 12.7 mm from the outflow end of the jacket 12 are arranged) ■

Inner diameter of the container 46 76.2 mm

Length of the container 46 (up to the

Nozzles 48) 91.4 cm

In this experiment, the following reactants became at the following introductory points supplied: Natural gas, which mainly consisted of methane and had a calorific value of around 8900 kcal / m, was used as fuel and was through entry 24 into the Antechamber 26, and from there through openings 30, it was used as an oxygen-rich oxidizing agent technical oxygen of a purity of more than 99 $ molecular oxygen and by tangential entry 32 was introduced. The liquid starting machine, which was fed through the bores 34, was a rucks tandsb'l, which from the kätalytischeη oil refinery purchase received wai? and had the following metrics:

AI> I * GraVity at 15.6 ⁰ C (ASTM-D ^ 287) ü!

Specific weight at 15 »6 ⁰ O

(ASTM D * 287) x 1.085

Viscosity, SUS at 54 "4 ⁰ C (ASTM D-S8) 26S Viakosität, SAEs at 98.9 ° 0 (ASFM D" 88) ^ 7.5

temperature deä 5 ^ p

(ASTM P-I160)

Carbon content; 89.0

8.1

- ■ 1.2

A series of experiments were carried out with the combination of apparatus and reactants described above in compliance with all the provisions of the invention, the ratio of fuel to oxidant being varied from experiment to experiment in order to illustrate a range of operations in which the combustion product stream formed was 1 ) Is oxygen starved and of a reducing nature, 2) substantially balanced at approximately stoichiometric conditions, 3) is oxygenated and oxidizing in nature, and 4-) contains a large excess of unreacted oxygen. At the same time, the amount of liquid starting material added in the second stage of the process was adjusted in this series of experiments so that the percent total combustion that could theoretically be achieved in each experiment remained approximately the same (about $ 29 to $ 30) and the. Residence time of the complete reaction mixture remained essentially constant at about Λ5 milliseconds in each experiment before the final cooling.

The main working conditions of these four experiments and the results obtained with regard to the carbon blacks formed are summarized in Table I below.

Table I.

Experiment No. 4-424 «· 70 64 62 74

Amount of oxygen supplied,

56.64 56.64 56.64 56.64

Amount of natural gas supplied, Nm ⁵ 35.4 28.32 17.7 8.5

Pressure in the combustion chamber, atü 0.84 0.77 0.53 0.35

Amount of liquid input material supplied,

l / hour 46.6 51 * 1 62.5 70

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_ 19 -

Table I (cont.) .

70 64 62 74

32.21 31.75 32.66 34.47 82.5 79 81.5 82 125 149. 147 135 185 241 242 225 188 173 169 168

Injection pressure for fluid

original raw material,

atu 10.2 12.3 15.1 17.6

Received soot

Production speed, kg / hour

Nigrometer value surface ² , m ² / g

Color strength

DBP absorption ⁴ "

Extractable inventory

parts ?, wt .- # 0.1 0 0 0.1

1) The nigrometer values represent the relative light reflection compared to a standard grind of soot in oil. The lower the nigrometer value, the darker it is is the soot, i.e. the greater its color depth.

2) Measured by iodine absorption

3). Relative opacity of a carbon black in the weight ratio of 1:30 is mixed with a standardized zinc oxide dispersed in a standard oil and compared to a standard set of comparative carbon blacks tested under the same conditions will.

A) The DBP absorption values are given in ml of dibutyl phthalate, which is absorbed per 100 g of carbon black, when eö mixed with the carbon black in accordance with ASTM-D-2414 (1965T)

will, until the merging point of the mass is reached is. These values indicate the degree of "structure" or the agglomeration of the particles and the network formation.

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5) Ingredients removed from the carbon black when a sample of the carbon black is 10 times by weight Toluene is refluxed for 12 to 22 hours.

The following is noteworthy when considering the above values:

1) The carbon blacks produced in the tests have a unusually high "degree of structure" and a surprising

^v seeing small particle size, especially if one takes into account the theoretical overall percent combustion 29-30 $. Even the coarsest of these soot is finer than the one currently used. commercially available super abrasion furnace carbon blacks.

2) The soot yields achieved in these tests are close to $ 50 of the total used in the process Carbon. This efficiency is usually only achieved with much coarser carbon blacks of inferior quality.

3) -The one made in a fairly wide range Variation of the oxygen / fuel ratio in the combustion stage in those described above Experiments did not significantly change the efficiency expressed as carbon yield and made it worse the basic physical properties of the carbon black formed do not. (However, xj in the tests in which the combustion conditions closer to the stoichiometric ratio of oxygen and fuel, slightly finer soot educated.)

Given the above "high structure" and the Excellent reinforcement properties of these carbon blacks were used as samples of each product from the four experiments described in mixtures based on natural rubber and on

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of a synthetic styrene-butadiene rubber. The mixtures were made according to those customary in the industry Recipes made from the following components (parts by weight):

Table II *

Components natural rubber synthetic rubber

Polymeres ._ 100 (Smoked Nr.1) 100 (SBR-1500) Zinc oxide 5 5 -

Stearic acid 3 1.5

Sulfur 2.5 2 ä

Accelerator (1) 0.6 2

Soot 50 50

(1) Benzothiazyl disulfide.

The -properties-of the compounds and vulcanized products are in given in the following table »

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Tatelle III

70 Natural rubber 62 74 . 70 SBR 15Ο0 ² 74 Attempt no. 60 64 68 62 64 64 62 63 Mooney viscosity, ML-4 ^r at 100 ^° C. 70 68 68 Shrinkage during extrusion 41.9 41.7 at 50 ° C, £ 250 229 2J9 239 42.2 37.8 229 ο tensile strength, kg / cm ² 188 261 177 154 239. 281 230 183 «> Module at 300 ^ elongation, kg / cm 380 167 400 450 300 195 207 380 ΐ
ι * - elongation, # 69 450 72 68 74 400 320 70 -η. Hardness, Shore A2 69 76 76

(i) The tensile strength and hardness test specimens were vulcanized at 145 * for 30 minutes.

'C

(2) The samples for the determination of tensile strength and hardness were vulcanized at 145 ° C for 50 minutes.

to-

The above, achieved with the rubber Results generally confirm the high degree of finely divided structure and the ability of this series of carbon blacks to be reinforced for rubber. However, it is for that It will be apparent to those skilled in the art that special modifications in the mix composition is much more extensive Exploitation of the reinforcement ability of these carbon blacks would allow.

Example 2

Using the apparatus described in Example 1 a series of experiments was carried out under exactly the same conditions as those mentioned for experiments 4424-62 were carried out, but with small amounts of potassium chloride in the hot combustion products immediately were introduced prior to the introduction of the liquid starting material in order to determine whether the "structure-reducing" effect of alkali compounds (as in U.S. Patents 3,010,794 and 3,010,795) also in view of the extremely strong tendency to Formation of "high structure" soot, which were described in Example 1, would be retained. |

The conditions of these experiments and those obtained thereby Products are listed in the following table together with the results of comparative test 4424-62.

represents. ■■ ".- '" *

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IN THE attempt 62 60 201 59U - Table IV 56.64 56.64 Supplied oxygen 17.7 17.7 No. 4424- amount, Nm ^ / hour 59 58 Amount of natural gas supplied 0.53 0.53 Nm * / hour 56.64 56.64 Pressure in the burn 62.45 62.45 nungskammer, atü 17.7 17.7 Liquid output material, l / hour 15.1 15.1 0.53 0.53 Injection pressure for liquid output 0 3 62.45 62.45 material, atü Amount of KCl supplied *, g / hour 32.66 32.21 15.1 15.1 Formed soot 81.5 81 Production speed 147 120 6th 9 speed, kg / hour 242 245 Nigrometer value 169 108 Surface, m / g 31.3 31.75 Color strength 0 0.2 82 83 DBP absorption 113 96 Extracted inventory 235 232 parts, weight -i » 93 94 * 0.2 0.1

(*) Supplied as an aqueous solution containing 10 g KCl / l ent

held

These results show that the added potassium compound is able to maintain the "structure" without major deterioration in the yield or deterioration in the reinforcing ability of the individual particle sizes to reduce exceptionally strong.

The carbon black obtained in Experiment 4424-60 of this series was used in the rubber compounds described in Example 1 tried. The results obtained are in the following table together with the corresponding figures for the used here as a comparative experiment, already in both

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- "37.8 51, t 239 281 230 281 177.1 148 207 '176 400 510 320 430 72 66 76 70

201 59H SlS

game 1 mentioned attempt 4424-62 specified.

table V ...

".-. '■ _ - Natural rubber · SBR-1500' Experiment No. 62 60 62 60

Mooney viscosity,

ML-4 ¹ at 100 ⁰ C 68 60 68 59

Shrinkage at
Extrusion at
50 ⁰ C, Jo

Tensile strength, kg / cm. cj? ^ i cj \ j cut g

Module at $ 300 elongation,
kg / cm ²

Elongation, ^
Hardness, Shore A2

These results confirm that the carbon black from Experiment 60, the one with. Addition of KCl was produced, has less "structure" and a softer rubber in a given mixture with a large decrease in the modulus values. and increased tensile strength and elongation. '

Example 3 '

The same device as in Example 1, but with |

the reaction zone enclosing container 46 of Fig. 4 had a different size was used. Uin

significant · changes in the dwell time between -dem.

Injection of the liquid starting material in the ■ '·· Level 2 and cooling in level 3; the procedure according to of the invention without major changes in throughputs and other conditions of the process

occur, the size of the reaction zone was 46 at

this series of experiments from experiment to experiment

Even; äU, e Farm: des Combustion Urigarauma% 6, in the Vfa, r inaoferri andtera »ials; the inner january 12

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was not of uniform diameter along its entire length. Instead, it consisted of cylindrical ones Split 19 »05 mm in diameter at each end, one cylindrical part of 38.1 mm in diameter, in the middle and connecting frustoconical transition sections between the central portion and the end portions. The combustion chamber 16 in this device thus had a somewhat larger volume than that in the examples 1 and 2 used devices despite the fact that the length of the inner jacket 12 in the present Fall was only 152.4 mm from the distributor plate and only 114.3 mm from tangential entry 32

Otherwise, the arrangement of the parts and the working conditions essentially the same for this example as mentioned in example 1. the Conditions for this series of experiments and the results obtained are summarized in the following table, where again the corresponding information for experiment 4424-62 is repeated for comparison.

Table VI _{Run No. 0} 4424-62 24-32 59-36 59-65

Supplied sour
substance, Nm3 / hour 56.64 56.64 56.64 56.64 Supplied natural gas,
Nm '/ hour 17.7 17.7 17.7 17.7 Pressure of burn
nungskammer, atü 0.53 0.63 0.63 0.63 Liquid output
material, l / hour 62.45 66.24 60.94 65.1 Total combustion,
io the theory 29 27.5 29.5 28 Injection pressure for
liquid output
material, atü 15.1 16.52 14.76 16.2 Diameter of the Be
holder 46, mm 76.2 152.4 50.8 152.4

Length of the container 46 to the nozzles 48,

2015 314

Table VI (cont.) Trial No. 4424-62 24-32 59-36 59-65

Dwell time in the

Zone 46 in front of the

Cooling, milliseconds.

the 15 30 5 105

Formed soot

32.66 35.38 29.94 31.3 81.5 83 81.5 85 147 121 121 140- .242 209 257 224 169 172 163 158

Production speed, kg / hour nigrometer value. Surface area, m / g color strength
DBP Abs ο rpt i ο η, ml / g

Extracted ingredients, wt .- $ 0 0 0.2 0

The above results show that even with short residence times, on the order of 5 milliseconds or at 20 times this time, neither the basic character of the carbon black formed nor the yield Soot change a lot, at least not to particularly bad values. -

Example 4

Further experiments were carried out using the apparatus combinations described in Example 3 for experiments 59-36 tion, i.e. with the double frustoconical combustion chamber (Diameter 19.05-38.1 mm) together with. the reaction zone 46 of 50.8 mm internal diameter and 61 cm length up to the nozzles 48 carried out. The conditions these experiments and their results are in the following table together with those for comparison repeated values for the experiment 59-36.

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Table VII Experiment number, 59-56 59-52 59-56

Supplied oxygen,

Nm ⁵ / hour 56.64 56.64 56.64

Natural gas supplied, Nm ⁵ / hour. 17.7 7.08 42.48

Pressure in the combustion chamber, atm

Liquid starting material, l / hour

Injection pressure for

t liquid starting material, atü

Gesaratverbremmung, '$> the theory

Residence time in the react. tion zone 46, milliseconds 5 5.5 5.5

Formed soot

0.65 0, 49 0 , 74 60.94 54, 9 28 , 77 14.76 11 95 5 , 62 29.5 37 36

Production speed 29.94 23.59 19.05 speed, kg / hour 81.5 82 83 Nigrometer value 121 150 103 Surface *, rn ² / g 257 247 Color strength

Extracted components,

Wt .- ^ 0.2 0 4.8

* Measured by nitrogen adsorption using the BET method.

The carbon black produced in Run 59-52 was generally the same as that produced in Comparative Run 59-36 Comparable to carbon black, although the yield was somewhat lower, no doubt due to the somewhat higher yield on the Theoretical percentage of total combustion with which this experiment was carried out. The one trying However, the soot formed 59-56 was completely unsatisfactory due to the extremely high content of extractables. The extract from this soot was so high that

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a color strength could not be determined.

After the reaction zone 46 was removed, the observation of the injection of the liquid feedstock into the hot combustion products formed under the conditions given in the table above for Run 59-56 was found to be the cause of the poor results in this run could be that the liquid starting material had no sufficient driving force in this experiment to work well in the interior of the ä penetrate vorbeiströmendeh hot combustion products 34 to the openings. Instead, the liquid feedstock has merely been entrained along the circumference of the flow of hot combustion products with the adverse consequences described above.

Example 5

The device was in the same manner as in Example 1 (and shown in Fig. 1, 2, 3 and 4) designed, but larger in order to enable much higher throughputs. This device had the following essential dimensions:. . |

Inner diameter of the inner jacket 12 50.8 mm

Length of the jacket 12

measured. from the distribution plate 28 330.2 mm

measured from the tangential entry 32 279.4 mm,

Durometer of the openings 30.3.2 mm

(There are 7 openings: 1 in the

Middle and 6 equidistant from it

with the centers on a 38 »2 mm

Circle)

Diameter of the holes 34 0.76 mm

(there are 8 holes at a distance of 45 °, 25.4 mm from the outlet end of the.

Coat. 12)

Inrial diameter of the container x3 46 152.4 min.

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Length of the container 46 (to the nozzles 48) 213.4 cm

In this example the reactants used were and their introduction points are the same as in Example 1 with the difference that as the liquid starting material, introduced through wells 34 was a catalytic cracking residual fraction was used that came from another refinery and had the following key figures:

API gravity at 15.6 ⁰ C +1.1

Spez.Gewicht at 15.6 ⁰ C 1.065

Viscosity, SUS at 54.4 ° C 75.9

Viscosity, SUS at 99 ° C 39.6

Estimated 50 ^ distillation point 358 ° C

Carbon content 89.1% by weight Hydrogen content 8.45 "

Sulfur content 1.89 "

Ash '0.01 "

With the combination of apparatus and reactants described above, a number of Experiments conducted using highly oxidizing combustion reaction conditions in the first stage each trial was maintained, but the amount of liquid starting material varied from trial to trial was changed to increase the percentage of theoretically complete combustion in reaction zone 46 change.

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Table VIII Attempt no. P-30 " 320 P-32 P-34 P-36 Supplied sour
substance, Nm3 / hour 453 0.5 453 453 283 Supplied natural gas,
NnP / hour 68 81.5 - 68 68. 42.5 Pressure in combustion
chamber, atü. 0.49 128 0.49 0.49 0.18 Back pressure of the combustion ¹ -
products to the
Openings 34 0.35 0 0.35 0.35 0.14 Liquid output
material, l / hour 621 492 405 257 Injection pressure for
liquid starting
material, atü 20.4 15.5. 10.5 7.7 * Percentage of theo
total retic
burning 29 36 43 43 Dwell time in the reac
tion zone 46 in front of the
Cooling, milliseconds 13 14th 15th 24 Formed soot Production speed
speed, kg / hour 211.4 *
125 95.3 Yield, kg C / l Aus
gang material 0.42 0.3 0.37 Nigrometer value 77.5 72 80.5 BET surface area, m ² / g 295 481 140 Extracted inventory
share 0 0 0

* Of the 8 openings 34 were two during this experiment clogged.

It should be noted that the combustion reaction conditions for the first three runs in this series between oxygen and fuel gas were kept so constant that the combustion pressure in the first stage of the method 0.42 atü and the back pressure in the Openings 34 hot combustion pro-

0 0 8 8Λ 3/1262 '

in the second stage of the process was 0.35 kg / cm. By reducing the amount of in the second Liquid feedstock introduced, but while maintaining good feedstock penetration In the hot combustion products, the fineness of the soot formed was very much reduced, E.g. to a nigrometer value of 77 »5 in the experiment P-32, which is only $ 36 of the theoretically complete total combustion was carried out, and to a nigrometer value of only 72 at 43? «the theoretically complete one Total combustion in experiment P-34. Although at the same time the yields of soot per liter of the liquid As the starting material fell off, they nonetheless remained in any case, taking into account the quality of what was formed Soot at a level that was previously not achievable with any known process.

If, however, in experiment P-36, the combustion conditions in the first stage were changed so that the pressure therein to below 0.21 atm and the back pressure of the hot combustion products in stage 2 to less than 0.21 kg / cm, there was a great deterioration in the yield / nigrometer ratio of the formed Product (even if the injection of the liquid starting material by blocking two orifices 34 was regulated so that the starting material penetrated well into the combustion products). So it is determine that the quality of the carbon black produced in Experiment P-36 was not significantly better than that of the soot formed in the experiment P-30 and yet the yield by 0.13 kg per liter of the liquid consumed Source material was worse.

009843/1 262

20.159H

Example 6

The device designed according to Pig.5 was introduced the reactants used to which a trained according to Figure 4. Reaction and cooling zone with the paddles 44 and 44 'was connected. The overall device had the following main dimensions:

The inner jacket 62 had an inner diameter of 50.8 mm over the first 89 mm of its length, then gradually tapered over the next 63.5 mm of its length until it reached an inner diameter of 20 mm, which it over the remaining length of 25 , 4 mm retained. i

Six intersecting pairs of holes 70 and holes 74 were spaced 60 apart around the circumference of the Inner jacket 62 is provided, each bore 70 having a diameter of 2.03 mm and each bore 74 a diameter of 0.76 mm.

Two holes 34, which had a diameter of 0 * 51 mm, were at a distance of 180 ° around the circumference of the Inner jacket 62 at a distance of 12.7 mm from his Outflow provided.

The container 46 had an inner diameter of 76.2 mm as in Example 1, but the distance was the nozzles 48 Λ for the cooling liquid from the end face of the flange 44 'only instead of 45.7 cm 91.4 cm as in Example. 1

The following reactants became involved in the following Introduced mentioned bodies: Technical oxygen, which has a purity of at least 99 $ molecular Had oxygen, the six holes were 70 through a balanced distribution system with the help of the lines 72 supplied. It was also balanced by a Distribution system, a liquid fuel is supplied to all the bores 74 via the supply lines 76, the consisted of the same residue fraction, which in

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Example 5 was used as a liquid starting material. At the same time, this same liquid starting material became as in example 5, supplied to all nozzles 34 as liquid starting material.

A series of _comparisons were made with the above-described combination of apparatus and reactants in accordance with the teachings of the invention, varying from trial to trial the ratio of liquid fuel to oxidizer in step 1 of the process by a range of operations in which the combustion product stream produced therein is 1) essentially balanced at approximately stoichiometric state, 2) rich in oxygen and of an oxidizing nature, and 3) contains a large excess of unreacted oxygen. At the same time, the feed amount of the liquid starting material introduced through the nozzles 34 in the second stage of the process-s was adjusted so that the total percentage of theoretically complete combustion in each experiment was approximately the same (about $ 28 to $ 29) and the residence time of the complete reaction mixture also remained essentially constant at about 8 milliseconds in each attempt before the cooling stage of the process.

The essential conditions of these three experiments and the results obtained are as follows Table compiled.

ORtGiNA INSPECTED

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SS- Table IX

Attempt no. 1150-7 4380-61 4380-74 Supplied oxygen,
Nm ⁵ / hour 56.64 56.64 56.64 Liquid starting material
rial (level 1), 1 / hour
(mixed with O ₂ as
Fuel used) 21.6, 13.25 7.95 Pressure in combustion
chamber, atü Q, 7 0.49 0.35 ^A liquid usgangsmate-
rial (level 2), l / 3td. 56 66.6 69.6

30.8 27.2 27.2 83 82.5 85 112 - 119 99 197 225 195 179 170 - _; 147

Injection pressure for ^

liquid starting material

in level 2, atü 12 15.8 17.2

Formed soot

Production speed, kg / hour

'' Nigrometer value BET surface area, m ² / g coloring power DBP absorption, ml / g extracted components,

Wt .- ^ '0.2 0.2 0.1

The above experiments show as well as those in experiments described above again the flexibility of the method according to the invention and in this case in particular the possibility of the first stage, i.e. the combustion reaction over a fairly wide range of fuel / oxygen ratios even when using a liquid fuel, without the fundamental character of the carbon black product changing significantly or a large deterioration in the soot yield for a given total percentage theoretically complete combustion occurs.

0098A3 / 126 2

20159Η 36

The possibility of successfully performing the method according to the invention over a wide range of Conditions to produce a wide variety of soot types (including those with exceptionally fine particle sizes) in surprisingly high yields was illustrated by the above examples. However, it is take into account that these examples for the most part are only preferred parts of the total in question Represent the range of most of the variables, and the possibility of keeping the invention within the range taught here applicable ranges, but outside the preferred narrower ranges to be carried out by the exemplary embodiments actually illustrated will be apparent to those skilled in the art.

For example, it is evident that virtually any hydrocarbon-rich liquid feedstock can be used as the main raw material in the process according to the invention, provided that it can be introduced transversely in a plurality of small, contiguous liquid jets which enter the hot combustion product stream after this has reached a kinetic energy equivalent to a pressure of at least 0.21 kg / cm ". Also, numerous different combinations of oxygen-rich oxidant and liquid or gaseous fuel are possible in the first high temperature combustion stage of the process, provided that it is carried out at a pressure of at least about 1.26 ata and enough energy produced to the temperature of the Verbrennunrsprodukte at least about 2200 ⁰ C or when geai'beitrt on the oxygen rich side of the stoichiometric combustion, to close enough to increase this value that this temperature is established when the liquid hydrocarbon serving as the starting material in the

6AD LOCAL

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Combustion products is introduced.

Although several preferred embodiments of apparatus' doors for carrying out the high-performance process according to the invention and their functionality illustrated by examples describing specific operations performed therein, it is in turn obvious to those skilled in the art that numerous other special designs and arrangements in place of the used as described and illustrated herein

can be. For example, the exact form is the ~

Combustion chamber not of crucial importance as long as * the combustion reaction separately and but half the injection point of the liquid ■ starting material like this is carried out that the bite products of combustion with a suitable acceleration in an area in which they are essentially in one direction flow as a closed column before the liquid feedstock is introduced into the combustion products will, · .

Although cooling at least the walls of the combustion chamber and preferably also the walls of the reaction chamber with a liquid is generally the most convenient and economical way of working, devices suitable for other cooling methods or methods for protecting the materials used in these wall areas can be constructed are are applied Beispielsv / else i31 it possible a portion of the R _e used in the method according to the invention, action subscriber to or circulate through these walls to dissipate a portion of the heat from their immediate vicinity, although this regenerative cooling methods in the method according to the Obviously, the invention is much less interesting than in the usual carbon black production processes

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3?

injecting or blowing into the various reaction zones using heat generated by the process itself is absorbed, or preheated in another way. This preheating can often be beneficial when a relatively viscous liquid fraction is used as fuel or raw material for the soot zeuciuna.

BAO ORIGINAL

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Claims (17)

Claims 1.) Process for making carbon black by pyrolysis of a hydrocarbon feedstock in a zone of high Temperature obtained by burning a liquid fuel with an oxygen-rich oxidizing agent is generated, characterized in that a) this combustion at a pressure higher than 0.21 atü to generate an accelerated current of I. Combustion products of high temperature is carried out, which moves essentially in the form of a plug, b) that at a point where this stream has a kinetic energy corresponding to a pressure of at least 0.21 kg / cm, in this stream from its circumference a plurality of small contiguous jets of a liquid hydrocarbon feedstock in one is injected in such an amount that the total amount supplied is sufficient to ensure a temperature of at least about 2200 ^° C. and conditions suitable for carbon formation, and c) that the reaction mixture formed on a for " the formation of carbon particles discourages a sufficiently downstream location. 2.) The method according to claim 1, characterized in that ■ that the oxidizing gas has at least about 50 moles, preferably at least about 90 moles, of molecular oxygen contains. 3 ») Method according to claim 1, characterized in that a liquid fuel with a high content of hydrocarbon-containing components is used. «Afc 0.09 8 43/1 262 Ho 4.) The method according to claim 1, characterized in that one chooses the reactants and the reaction conditions in the combustion stage a) so that a heat eman
will. Meme amount of at least about 267 x 10 kcal / hour / m free 5.) The method according to claim 1, characterized in that the combustion at pressures between about 0.28 and 3.5 * preferably between about 0.7 and 2.1 atmospheres will. 6.) The method according to claim 1, characterized in that a reaction temperature of at least about 247O ⁰ C is reached during step b). 7.) The method according to claim 1, characterized in that the ratios of oxidizing agent to fuel are set so that about 70 to 500 %, preferably 100 to 550 % of the theoretical oxygen requirement for complete combustion is present and the amount of injected liquid hydrocarbon Feed is adjusted so that the percentage of the theoretical total combustion is less than about 50, preferably less than about 40%. 8.) The method according to claim 1, characterized in that the flow of combustion products when injecting the liquid feed has kinetic energy, which is equivalent to at least about 0.35 kg / cm and that the jets of the liquid feed material have a diameter between about 0.25 and 1 mm. 9.) The method according to claim 1, characterized in that the injection differential pressure behind the jets liquid feed is at least about 7 kg / cm '. 009843/1262 _B ADOR _IG INAL 20159U 10.) The method according to claim 1, characterized in that the quenching in stage c) between about 5 and loo Milliseconds after the liquid feed was injected in stage b). 11.) The method according to claim 1, characterized in that. Immediately after the injection of the liquid Einsät zmaterials in stage b), which flows generally downward, can expand abruptly and assume a much larger cross-section. . A. 12.) Device for the production of soot, consisting of an elongated, laterally enclosed chamber with relatively thin side walls of relatively high thermal conductivity, at the upper end of which a high-performance mixed burner for two media is arranged, as seen in the flow direction, and a device near its lower end, as seen in the flow direction includes the introduction of a quenching medium, characterized in that lenwaseerstoffen at a point between the ends means for the injection of a plurality of small, coherent cross beams from liquid coal 'from the circumference are arranged. * 13.) Device according to claim 12, characterized in that that they ein.Einrichtung for cooling the longitudinal walls of the contains elongated chamber with a liquid coolant. 14. "') Device according to claim 12, characterized in that . that the burner for the mixture of the two media has a distributor for the division of the liquid fuel into has a series of small individual streams which flow essentially parallel to the longitudinal axis of the chamber and further characterized by at least one lateral. •. before the inlet line for the oxidizing agent, the 20159H tangent to the inner circumference of the side wall of the combustion chamber just below the manifold, in Direction of flow seen, is connected. 15.) Device according to claim 12, characterized in that the burner has a number of arranged in pairs Holes ^ them at a larger angle close by the upper end of the chamber converge and further characterized by means for distribution of the liquid fuel and the oxidizing agent on opposite holes each forked Couple. 16.) Device according to claim 12, characterized in that the cross section of the chamber at the upper end is considerable is greater than where the liquid hydrocarbon is injected. 17.) Device according to claim l6, characterized in that the cross section of the chamber is immediately below the point of hydrocarbon injection is immediately increased by at least four times. 009843/1262 Le e fs e11 e