Search results
Results from the WOW.Com Content Network
In fact, the Environmental Protection Agency considers recycling a "critical" part of the United States economy, contributing to tax revenue, wages, and job creation. [31] By facilitating scrap handling and improving its efficiency – from "end of life" scrap to repurposing scrap throughout the production stage ("in-house" scrap) – aluminium ...
The Hall–Héroult process is the major industrial process for smelting aluminium. It involves dissolving aluminium oxide (alumina) (obtained most often from bauxite , aluminium 's chief ore, through the Bayer process ) in molten cryolite and electrolyzing the molten salt bath, typically in a purpose-built cell.
The Hall-Héroult electrolysis process is the major production route for primary aluminium. An electrolytic cell is made of a steel shell with a series of insulating linings of refractory materials. The cell consists of a brick-lined outer steel shell as a container and support. Inside the shell, cathode blocks are cemented together by ramming ...
Anodes that conduct too much heat will oxidize rapidly, reducing or eliminating their smelting efficiency, called "air burn" in industry parlance. [ 10 ] Mechanical strength ( compressive strength , Young's modulus , tensile strength )
Due to the concentrations of fluorides and cyanides in spent potlining, and the tendency to leach in contact with water, the US Environmental Protection Agency (USEPA) listed the materials on 13 September 1988 (53 Fed. Reg. 35412) as a hazardous waste (K088) under 40 C.F.R., Part 261, Subpart D. [6] International shipment of SPL is subject to ...
The most promising was the Heroult-Hall process, separately developed by P T L Heroult in France and C M Hall in America in 1886-1887, but it required large amounts of electricity. The rights to using the process in Britain were obtained by the British Aluminium Company, which was formed in 1894.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
The Hall–Heroult process produces aluminium with a purity of above 99%. Further purification can be done by the Hoopes process. This process involves the electrolysis of molten aluminium with a sodium, barium, and aluminium fluoride electrolyte. The resulting aluminium has a purity of 99.99%. [46] [143]