Search Results for mine

This chapter describes the process steps in the production of smelter grade aluminum, the environmental issues with aluminum production, and the importance of recycling. It also provides a discussion on the refining, or Bayer, process and the smelting, or Hall-Héroult, process.

This chapter begins with a brief review of the different types of surface treatments and coatings used in industry and their effect on properties and performance. It then discusses the importance of corrosion and wear treatments and the consequences of failing to properly implement them in critical industries such as mining, energy production, transportation, and mineral and chemical processing. The chapter also describes basic approaches to dealing with corrosion and wear in steel.

This chapter traces the history of steelmaking over three millennia, from the discovery of martensite in a mining tool dating from the twelfth century B.C. to the nineteenth century development of the Bessemer and Siemens processes. It also describes the work of early metallographers who discovered many phases and microstructures associated with steel and gave them their now familiar names. The chapter concludes with a brief discussion on the emergence of continuous casting and the subsequent development of strip casting production techniques.

Steel castings are produced in thousands of designs for different applications. They fill needs in many industries, including transportation, construction machinery, earthmoving equipment, rolling mills, mining, oil and gas exploration, and power generation. This chapter touches upon the variety of applications for which steel castings can be supplied and the ranges of casting size and complexity. Photographs in this chapter provide an understanding of these applications, their size and complexity, and the types of cast steels produced.

Beryllium is the 44th most abundant element on Earth, with an estimated concentration of six parts per million in the Earth’s crust. It is found in various forms in more than 100 minerals, two of which, beryl and bertrandite, account for most of the beryllium produced throughout the world. This chapter describes where and how beryllium is obtained and provides facts, figures, and insights on global supply and demand.

This chapter is a chronological account of the development of ironmaking in colonial America from 1645 to 1870. The discussion covers the spread of ironmaking in many of the colonies in the northeast, canal building in Pennsylvania, the replacement of charcoal by anthracite coal in ironmaking, the life of ironmaking pioneer John Fritz, and the rapid increase in ironmaking for the railroads.

This appendix includes selected references on topics related to the production and application of superalloys, including properties and microstructure; melting/ingot breakdown; forging/powder metallurgy; machining, heat treating, joining, refurbishment/repair; investment casting; coatings/corrosion; and modeling.

This chapter describes some of events and developments that helped drive the commercialization of beryllium and its acceptance as an engineering material. It traces the growth of the domestic beryllium industry from its origins in the 1920s to the present time, and provides a status update on the primary beryllium producers throughout the world.

This chapter provides a fundamental understanding of beryllium reduction thermodynamics as a prerequisite for subsequent chapters on extraction, chemical processing, and corrosion. It examines a number of reduction methods along with a potential refining process, highlighting the challenges encountered with each.

This chapter describes some of the processes used to concentrate beryllium-rich minerals from ores. It discusses the flotation of bertrandite and phenacite from calcite, mica, fluorspar, and quartz-containing ores, the flotation of beryl from pegmatitic gangues and low-grade deposits, and the use of chemical activators and conditioning agents. It also explains that hand sorting is still very common because of processing challenges and inefficiencies.

This chapter describes some of the chemical processes that have been developed to extract beryllium from different types of ore. It covers the Kjellgren-Sawyer sulfate method, the Degussa method, Copaux-Kawecki fluoride extraction, solvent extraction, and leaching and settling. It also provides information on electrolytic extraction and the use of electrorefining.

This chapter reviews the basic chemistry of beryllium metals and compounds, including beryllium hydroxide, beryllium carbonates, beryllium fluoride, and beryllium chloride. It discusses the uses as well as application challenges of various forms of beryllium and includes information on their chemical properties and reactions.

This chapter describes the procedures and processes used to chemically analyze beryllium samples. It discusses gravimetric, volumetric, colorimetric, and fluorometric techniques, radiochemical separation and assay, and the use of emission spectrometry and polarographic methods.