Separation Technologies for the Industries of the Future (1998) / Chapter Skim
Currently Skimming:
10 Cross-Cutting Issues for the Materials Processing Industries
10 Cross-Cutting Issues for the Materials Processing Industries
Pages 87-96
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 87... ...
These are: removal of impurities from feedstock; metal purification; separation of scrap; prevention of gas inclusions; separation of components from dilute gaseous streams; separation of components from dilute aqueous streams; and water removal. In addition, the panel identified one technology area with the potential to meet some of these needs and three enabling technologies.
|
From page 88... ...
The forest products industry needs separation technologies for better separation of the contaminants from the hot gases produced in black liquor gasification and of VOCs from wet air streams. Separation of components from dilute aqueous streams are an issue for all of the materials processing industries.
|
From page 89... ...
The aluminum, steel, metal casting, and glass industries each identified separation needs that could be classified as materials handling and sorting or separation methods based on the physical properties of components. In many cases, the analytical technology has already been developed, and scrap separation processes are in place.
|
From page 90... ...
In use, these suspensions must be agitated to prevent or limit settling of the medium. For separations of coarse particles, such as metals from the nonferrous components of shredded automobile scrap, large, relatively quiescent vessels can be used, but finer separations may require a second force, often a centrifugal force, to hasten and sharpen the density difference.
|
From page 91... ...
Separation Processes Based on Magnetic and Electric Forces Solids can be classified as ferromagnetic, paramagnetic, or diamagnetic. Relatively few are ferromagnetic, but those that are respond to magnetic force so strongly that magnetic separation is the most common and efficient method for separating them.
|
From page 92... ...
Eddy currents, in turn, interact with the magnetic field to generate repulsive forces, the magnitude of which are related to the conductivity, shape, mass, and size of the particles and the intensity of the magnetic field. Eddy current separators are based on either rotating disc permanent magnets or linear motor electromagnets for the generation of time dependent magnetic fields.
|
From page 93... ...
ENABLING TECHNOLOGIES The panel identified three enabling technologies that would help the materials processing industries meet their separation needs: lower cost oxygen; particle characterization; and online diagnostics and sensors. Lower Cost Oxygen Several industries, including the aluminum, steel, and glass industries, have stated that inexpensive, high-purity oxygen would be beneficial in combustion processes.
|
From page 94... ...
For example, recent detections of chlorinated wastes in the aqueous streams leaving pulp and paper processes have stimulated research and development on nonchlorine-based bleaching.
|
From page 95... ...
1 III CROSS-CUTTING SEPARATION ISSUES page 95
|
From page 96... ...
page 9Wblank
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.