Industrial Carbon and Graphite Materials. Группа авторов
carbon anodes, and refractory materials. Further, modern electronics would not exist without the help of graphite materials during their production. Finally, stiff and lightweight structures can be obtained with carbon fiber reinforced composites. Bulk materials like carbon blacks are essential for automotive tires and for paints and in the rubber industry. Activated carbon materials help keep our environment clean. Mentioning all the other plentiful applications would go beyond the scope.
With nanoscaled allotropes, the element carbon is just recently reinventing itself. Two Nobel Prizes were granted for fullerenes and graphenes. Prominent industrial applications are expected to follow.
However, in general the knowledge about industrial carbon and graphite materials is restricted to a small community of experts. In fact, information about their raw materials, production, and applications are not easily available in one comprehensive compendium. Information has to be gathered from various sources. For many decades, the Ullmann’s Encyclopedia of Technical Chemistry has been one of these sources.
Thus, the editors combined updated single existing chapters of the Ullmann’s Encyclopedia of Technical Chemistry to the backbone of one comprehensive book about technical carbon and graphite materials. New chapters have been added to complete the overview.
The content of the book is completed by the IUPAC nomenclature on carbon as a solid.
This book is addressed to a widened circle of interested people from academia, students, and commercial and technical employees in various industries.
The editors thank all authors for their support and the publisher for his uncomplaining cooperation.
The Editors, June 2018
Hubert Jäger
Wilhelm Frohs
1 Introduction: The Future of Carbon Materials – The Industrial Perspective
Hubert Jäger1, Wilhelm Frohs2, and Tilo Hauke2
1 Technische Universität Dresden, Institute of Lightweigth Engineering and Polymer Technology (ILK), Hohlbein Street 3, Dresden, 01307, Germany
2 SGL Carbon GmbH, Werner‐von‐Siemens‐Street 18, 86405 Meitingen, Germany
1.1 Overview
This chapter provides information about the industrial importance of various carbon and graphite materials. Carbon and graphite materials are mostly unknown to the public. They are obvious in few consumer products only, such as lead pencils, or in sporting goods as carbon fibers, for example.
In contrast, the importance of carbon materials for the production of iron, steel, and aluminum is not common knowledge. The iron, steel, and aluminum industry created in 2011 a global market value of around 1100 billion €. This is equivalent to around 50% of the value of the global annual crude oil production. Although we will not consider metallurgical coke in this chapter, the market value should be mentioned; it is around 155 billion €. Also not considered here are carbon black (11 billion €) and activated carbon (1.8 billion €). The market value of carbon materials in total (without metallurgical coke) is at around 42 billion € (Figure 1.1). The biggest contributor with a market value of 18 billion € is carbon anodes for aluminum electrolysis. Within the group of polygranular carbon materials, the anodes are followed by graphite electrodes for the production of electric arc furnace (EAF) steel with a market value of six billion €. Smaller markets are cathodes for the production of aluminum (1.4 billion €), fine‐grained graphite for multifold applications (0.7 billion €), furnace linings for blast furnace steel production (0.3 billion €), and carbon electrodes for the production of silicon (0.2 billion €). Other carbon materials like natural graphite, carbon fibers, and graphite for Li‐ion batteries play a minor role versus the conventional carbon products yet. Changes may happen in the near future driven by the need for the efficient storage and use of energy. The market for conventional carbon materials will continue to grow driven by the demand coming from the BRIC countries (Brazil, Russia, India, and China).
New forms of carbon, the carbon nanomaterials, created huge expectations but are currently not produced in an industrial scale with the exception of multiwall carbon nanotubes (MWCNTs). With the recent demonstration of the potential of graphene, a single graphite layer, in microelectronic circuits, we might see the beginning of a new market for carbon materials.
Figure 1.1 Carbon materials and their market value.
1.2 Traditional Carbon and Graphite Materials
Traditional carbon materials that are considered in this chapter are:
Graphite electrodes for melting of steel scrap.
Carbon electrodes for silicon production.
Cathodes for the aluminum electrolysis.
Furnace linings for blast furnaces.
Fine‐grained graphite for silicon production, machining, and others.
With the availability of stable electrical power networks, the electricity was used for heat generation and electrochemical industrial processes. Moisson demonstrated the first steel production with an EAF in 1891. The first EAF plant started its operation in 1906 (Remscheid, Germany). Simply baked carbon electrodes most probably with anthracite and carbon black as filler were used. The electrode diameter was small. In the 1920s more and more electrodes were used, which had been graphitized. The production of EAF steel grew to around 20 million t in 1950. After 1950 the production of EAF steel developed rapidly and exceeded 100 million t in the 1970s. The raw material in this time period was often pitch coke produced by chamber coking. Special coke grades, so‐called needle cokes, produced in the delayed coking process of crude oil refineries were developed later in 1960 and commercialized in 1970. This development represented a quantum leap in the quality of graphite electrodes. The most frequently used electrode became an electrode with 600 mm in diameter. As a consequence, there was substantial progress in the stability and efficiency of the melting process. The average consumption of graphite electrodes was reduced to below 4 kg/t steel. Further improvements in raw material quality, graphite electrode processing, furnace technology, and steelmaking process regulations reduced the graphite electrode consumption to about 2 kg/t steel in average (Figure 1.2). In particular the water spraying on top of the furnace roof was a genius idea to reduce significantly the graphite consumption due to oxidation. The lowest graphite consumption figure achieved so far was 0.74 kg/t with an electrode with a diameter of 800 mm on a direct current (DC) furnace.
Graphite electrodes are produced in mostly all continents. Traditional graphite electrode producers are GrafTech International, the SGL Group, and the Japanese producers Tokai, SDK, and Nippon Carbon. Later electrode producer followed in India and recently in China (Figure 1.3).
The production of EAF steel reached about 550 million t in 2020. Much stronger was the growth in blast furnace steel (Figure 1.4). This situation was created by the economic growth in China, which, as a young economy, is suffering the steel scrap required for EAF process. This will change over the times and the EAF process will pick up.