Manufacture of coke

Coke oven light oil is a by-product of the manufacture of coke for the steel industry. When coal is subjected to high temperature carbonization, it yields 16—25 Hters /tonne of light oil that contains 3—6 vol % of mixed xylenes. 

Sources of Raw Materials. Coal tar results from the pyrolysis of coal (qv) and is obtained chiefly as a by-product in the manufacture of coke for the steel industry (see Coal, carbonization). Products recovered from the fractional distillation of coal tar have been the traditional organic raw material for the dye industry. Among the most important are ben2ene (qv), toluene (qv), xylene naphthalene (qv), anthracene, acenaphthene, pyrene, pyridine (qv), carba2ole, phenol (qv), and cresol (see also Alkylphenols Anthraquinone Xylenes and ethylbenzenes). 

There are a large number of outputs that are produced as a result of the manufacturing of coke, iron, and steel, the forming of metals into basic shapes, and the cleaning and scaling of metal surfaces. For example ... 

The principal source of aromatic compounds is coal tar, produced as a by-product in the manufacture of coke. Gas tar, of which much smaller quantities are produced, also contains these same materials. Aromatic hydrocarbons occur in nature in Borneo and other petroleums, and they may be prepared artificially by stripping hydrogen atoms from the cycloparaffins which occur in Caucasus petroleum and elsewhere. They are also produced from paraffin hydrocarbons by certain processes of cracking, and it is to be expected that in the future aromatic compounds will be produced in increasing quantity from petroleum which does not contain them in its natural state. 

Ammonia is produced as a by-pioduct during the dry distillation of coal in the manufacture of coal-gas. and in the manufacture of coke in coke-ovens. Only a small percentage of the total nitrogen of the coal is recovered in the form of ammonia, the remainder is distributed in the coke, in the tar, as cyanide in the gas and ammo-niacal liquor, and as free nitrogen in the gas. The percentage amounts of the total nitrogen distributed in this manner are as follow ... 

Smaller amounts of ammonia are obtained as a by-product in the manufacture of coke and illuminating gas by the distillation of coal, and are made by the cyanamide process. In the cyanamide process a mixture of lime and coke is heated in an electric furnace, forming calcium acetylide (calcium carbide), CaCg. ... 

The principal source of aromatic compounds is coal tar, produced as a by-product in the manufacture of coke. Gas tar, of which much smaller quantities are produced, also contains these same materials. Aromatic hydrocarbons occur in nature in Borneo ... 

But unfortunately salicylic acid attacks the mucous membranes of the mouth and esophagus and causes gastric pain that may be worse than the discomfort it was meant to cure. Felix Hoffmann, a chemist for Friedrich Bayer, a German dye company, reasoned that the corrosive nature of salicylic acid could be altered by addition of an acetyl group and in 1893 the Bayer Company obtained a patent on acetylsalicylic acid, despite the fact that it had been synthesized some forty years previously by Charles Gerhardt. Bayer coined the name Aspirin for their new product to reflect its acetyl nature and its natural occurrence in the Spiraea plant. Over the years they have allowed the term aspirin to fall into the public domain so it is no longer capitalized. The manufacturers of Coke and Sanka work hard to prevent a similar fate befalling their products. 

Small amounts were also obtained as a by-product from the manufacture of coke or coal gas from coal. This source still provides about 1% of current American ammonia [1] (Table 11.1). Today most ammonia is produced by the direct combination of nitrogen and hydrogen. 

S. Nomura, Manufacture of coke balls in a rotary retort , in Proceedings of Twelfth Biennial Conference, BA, 1971, pp. 181-91. 

Coal preparation has been an Important segment of the coal Industry In the United States for approximately one hundred years. Its Initial use was In the production of high quality coal used In the manufacture of coke. By 1965 approximately 95% of metallurgical grade coal was processed through a coal preparation plant. The use of cleaned coal as a fuel for electric power generation and as an Industrial boiler fuel Is relatively recent. Studies conducted for the U. S. Department of Energy ( 1) and the... 

Metallurgical coal Coal used in the manufacture of coke for the steel industry. 

Another use for coal is in the manufacture of coke. Coke is nearly pure carbon produced when soft coal is heated in the absence of air. In most cases, 1 ton of coal will produce 0.7 ton of coke in this process. Coke is valuable in industry because it has a heat value higher than any form of natural coal. It is widely used in steehnaking and in certain chemical processes. 

The FMC process (Figure 17.4) is a multistage process for the manufacture of coke briquettes from high-volatile coals (Coal Age, 1960). In the process, the comminuted coal is oxidized, carbonized at low temperature, and calcined. On cooling, the low-tanperature tar or an extraneous binder is used. Weakly caking coals, which are not suitable for the production of coke by the conventional process, can be converted by means of this process into a suitable blast furnace coke. 

Sal ammoniac was manufactured in Edinburgh from the soot of bituminous coal from about 1756 by James Davie and James Hutton, and since Hutton was an intimate friend. Black was probably interested in the process. About the same time the Earl of Dundonald was making sal ammoniac as a by-product in the manufacture of coke. ... 

Ammonia was first produced in the United States on a commercial basis around 1890 as a by-product of the destructive distillation of coal in the manufacture of coke and coal gas. The first commercially successful synthetic ammonia plant in the United States was put into operation in 1921. It utilized the Haber-Bosch process, in which a preheated mixture of nitrogen and hydrogen was subjected to pressure in the presence of a catalyst. 

During vulcanization of rubber during manufacturing of coke or coal having high g5rpsum content Local exhaust ventilation or process enclosure... 

Childs, William Hamlin. By-Products Recovered in the Manufacture of Coke. Paper presented at the American Iron and Steel Institute, May 26, 1916. 

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