Tires Furnace black

Carbon black includes several forms of artificially prepared carbon, such as furnace black, channel black, lamp black, and animal charcoal. It is a finely divided form of carbon consisting of particles of extremely fine size. It is obtained by partial combustion (in 50% required air) of vapors of heavy oil fraction of crude oil in a furnace or by thermal cracking of natural gas. Carbon black is used in many abrasion-resistant rubber products including tire treads and belt covers. It also is used in typewriter ribbons, printing inks, carbon paper, and paint pigments. It also can be an absorber for solar energy and UV radiation. 

In the past decades the rapidly expanding automobile industry required increasing numbers of tires with various characteristics. This led not only to the development of new rubber grades, but also to the development of new carbon blacks required by the increasingly refined application processes and to the development of a new and better manufacturing process, the furnace black process. Unlike the old channel black process, this process allows the production of nearly all types of carbon black required by the rubber industry. It also meets the high economic and ecological requirements of our times. 

About 90% of the carbon black produced is used in the rubber industry as reinforcing filler in tires, tubes, conveyor belts, cables, rubber profiles, and other mechanical rubber goods. Furnace blacks are predominantly used in rubber processing. 

The development of highly reinforcing furnace blacks paralleled the creation of the synthetic-rubber industry. Improved cold butadiene-styrene elastomers reinforced with these new blacks give vulcanizates that are superior to natural rubb m tire treads. 

Acetylene carbon black is derived from the pyrolysis (thermal decomposition) of acetylene gas. The production volumes of acetylene black are extremely low compared to the billions of pounds of furnace blacks produced annually. Acetylene blacks are basically used where special compounding applications are needed, such as improved thermal conductivity. One of the larger areas of use is in the production of tire-curing bladders (because of the need for better thermal conductivity). 

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). 

Aromaticity is the most important property of a carbon black feedstock. It is generally measured by the Bureau of Mines Correlation Index (BMCI) and is an indication of the carbon-to-hydrogen ratio. The sulfur content is limited to reduce corrosion, loss of yield, and sulfur in the product. It may be limited in certain locations for environmental reasons. The boiling range must be low enough so that it will be completely volatilized under furnace time—temperature conditions. Alkane insolubles or asphaltenes must be kept below critical levels in order to maintain product quaUty. Excessive asphaltene content results in a loss of reinforcement and poor treadwear in tire appHcations. 

Carbon blacks (c.b.s) have been known since ancient times, for preparing Indian ink. From the 1920s, c.b. has been fabricated industrially on a large scale by the thermal decomposition of hydrocarbons (natural gas) or aromatic hydrocarbons. Of the total production, 90% goes into the rubber industry, and most of this is employed for the reinforcement of tires. Production capacity is at present 7.2 million tonnes/y and the armual production is 6.1 million tormes/y [244] 95% of this global fabrication is by the furnace c.b. process [245]. The specific surface area As (nr/g) in this case covers a range from a few tens up to more than 1500. It should be mentioned that c.b. is used as a filler for conducting polymers [246]. 

Several pyrolysis processes using reactors such as a fluidized bed (3 ), a shaft furnace, an extruder and a rotary kiln have also been studied in Japan. Pyrolysis using a rotary kiln has been studied since 1973 (U ). A pilot plant test was finished in 1976, and an actual plant with a capacity of 7,000 ton per year has been constructed at Sumitomo Cement Co., Ltd. in AK0 City, Hyogo Prefecture, in 1979 (l) The plant will recover fuel oil and carbon black from the scrap tires. 

A decomposition reaction is the opposite of a combination reaction. An example of a decomposition reaction in which a compound decomposes to form the elements in it is provided by the manufacture of carbon black. This material is a finely divided form of pure carbon, C, and is used as a filler in rubber tire manufacture and as an ingredient in the paste used to fill electrical dry cells. It is made by heating methane (natural gas) to temperatures in the range of 1260-1425°C in a special furnace, causing the following reaction to occur ... 

Impingement (Channel, Roller) Black Process. From World War I to World War II the channel black process made most of the carbon black used worldwide for mbber and pigment applications. The last channel black plant in the United States was closed in 1976. Operations still exist and are even being expanded in Europe. The demise of channel black was caused by environmental problems, cost, smoke pollution, and the rapid development of oil-furnace process grades that were equal or superior to channel black products particularly for use in synthetic rubber tires. 

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