Furnace black reactor

The furnace black process is currently the most important production process. It accounts for more than 95 % of the total worldwide production. The advantages of the furnace black process are its great flexibility in manufacturing various grades of carbon black and its better economy compared to elder processes. The following comparison makes this apparent for similar grades of carbon black, the production rate of one flame is ca. 0.002 kg/h for channel black, ca. 0.2 kg/h for gas black, and ca. 2000 kg/h for a modern furnace black reactor. However, in spite of the more advantageous furnace black process, the production processes listed in Table 27 (except for the channel black process) are still in use for the production of special carbon blacks which cannot be obtained via the furnace black process. 

Schematic drawings of some typical modem furnace black reactors are shown in Figure 50. They all have a gas-tight metal jacket. The reaction zone is coated with a ceramic inner liner, generally on an alumina base, which is stable to temperatures of ca. 1800 °C. Several quenching positions allow the changing of the effective volume of the reactor. This allows variation of the mean residence time of the carbon black at the high reaction temperature. Typical residence times for reinforcing blacks are 10-100 ms.

Most furnace black reactors are arranged horizontally. They can be up to 18 m long with an outer diameter of up to 2 m. Some vertical reactors are used especially for the manufacture of certain semireinforcing blacks [4.12] (Fig. 51). For further reactors, see [4.13]. 

Figure 50. Furnace black reactors A) Restrictor ring reactor B) Venturi reactor [4.15] C) Reactor with high-speed combustion chamber [4.16]...

Table 28. Processing data for high-performance furnace black reactors...

The ash content of furnace blacks is normally a few tenths of a percent but in some products may be as high as one percent. The chief sources of ash are the water used to quench the hot black from the reactors during manufacture and for wet pelletizing the black. The hardness of the water, and the amount used determines the ash content of the products. The ash consists principally of the salts and oxides of calcium, magnesium, and sodium and accounts for the basic pH (8—10) commonly found in furnace blacks. In some products potassium, in small amounts, is present in the ash content. Potassium salts are used in most carbon black manufacture to control stmcture and mbber vulcanizate modulus (22). The basic mineral salts and oxides have a slight accelerating effect on the vulcanization reaction in mbber. 

This is a more advanced partial combustion process. The feed is first preheated and then combusted in the reactor with a limited amount of air. The hot gases containing carbon particles from the reactor are quenched with a water spray and then further cooled by heat exchange with the air used for the partial combustion. The type of black produced depends on the feed type and the furnace temperature. The average particle diameter of the blacks from the oil furnace process ranges between 200-500 A, while it ranges between 400-700 A from the gas furnace process. Figure 4-4 shows the oil furnace black process. 

Characterization of carbon black primary particle size during the production process was realized at a furnace black production and a research plasma reactor (Dankers et al., 2003 Sommer et al., 2004, 2005). 

To simplify this paper, one reactor system and one feedstock were selected for the preparation of two distinct grades of carbon blacks. In the program as conducted six different reactors were studied with all of the reinforcing grades of furnace blacks being produced. A variety of feed materials were studied and a number of different gaseous and liquid fuels were employed. 

IINS work on coals (63,64) was extended to investigations of the proton-related properties of carbon blacks, such as furnace blacks, gas blacks, acetylene blacks, and others (65). During the production of carbon blacks in a reactor, the formation and growth of carbon particles is associated with a dehydrogenation process ... 

Plants operating the furnace black process can produce up to 16 10- t/a in a single reactor. The reactor lifetime is almost two years despite the high thermal and mechanical stress. 

Fig. 11.16 Layout of a modern furnace black manufacturing facility and cross section through the reactor (5) n il]...

Some work was done on the development of a process for the utilization of scrap rubber as feed for carbon black. Ground scrap rubber, presumably fabric-free, is heated with conventional carbon black feed stock oil, and the mixture utilized in a conventional furnace type carbon black reactor. Apparently, this process is not economically attractive. 

The ash content of furnace blacks is normally a few tenths of a percent but in some products may be as high as 1%. The chief source of ash is the water used to quench the hot black from the reactors during manufacture and for wet-pelletizing the black. 

The furnace black process was developed in the US in the 1920s and, since that time, has been greatly refined. It is a continuous process, carried out in closed reactors, which produces a flame carbon. Using petrochemical and coal tar oils as feedstocks, this... 

The first-mentioned material A is a pure zirconia ramming mix, which provides good service results at extremely high service temperatures like in carbon black reactors. In addition to its high price, specific mention is made of the high B.D., which corresponds to a material requirement of approximately 4.5 t/m. The second example B is a SiC-C-ramming material, which is occasionally used in blast furnace troughs but also in foundries. 

Kutrieb Corporation (Chetek, Wisconsin) operates a pyrolator process for converting tires into oil, pyrolytic filler, gas, and steel. Nu-Tech (Bensenvike, Illinois) employs the Pyro-Matic resource recovery system for tire pyrolysis, which consists of a shredding operation, storage hopper, char-coUection chambers, furnace box with a 61-cm reactor chamber, material-feed conveyor, control-feed inlet, and oil collection system. It is rated to produce 272.5 L oil and 363 kg carbon black from 907 kg of shredded tires. TecSon Corporation (Janesville, Wisconsin) has a Pyro-Mass recovery system that pyroly2es chopped tire particles into char, oil, and gas. The system can process up to 1000 kg/h and produce 1.25 MW/h (16). 

Fast-breeder reactors (FBR), 17 585-588 liquid-metal, 22 763 knowledge base for, 17 586 Fast color bases, 9 409—4 lOt Fast color salts,. 9 409-411 Fast-curing agents, 10 409-410 Fastening, ABS, 1 428 Fast extrusion furnace (FEF) blacks,... 

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