Solids-ejecting separators

Generally, the solids-ejecting separator is used when ... 

The residue was ejected intermittently by a double lock discharge system illustrated in Figure 20. It featured two piston valves ( ram valves ) and an intermediate chamber. With the first ram valve open and the second ram valve closed, the chamber was filled with both solids and product vapor at the operating pressure of the reactor. Then the first ram valve was closed and the second ram valve was opened, thus leading to an ejection of the chamber content into a cyclone, where the solids were separated from the vapor. 

Disk stack separators are vertical bowl centrifuges that are characterized by the presence of a nested conical stack of disks. The centrifuges are usually categorized by the method of solid removal from the bowl and include solids-retaining, solids-ejecting, and nozzle-discharge units. The feed enters the bowl at... 

Solids-ejecting disk stack separator. (View this art in... 

Figure 9.6 Liquid seal of solids ejecting DSC - Westfalia separator. 1, Feed 2, sealing-liquid discharge 3, sealing-liquid feed 4, centrate discharge.

In Secondary Ion Mass Spectrometry (SIMS), a solid specimen, placed in a vacuum, is bombarded with a narrow beam of ions, called primary ions, that are suffi-ciendy energedc to cause ejection (sputtering) of atoms and small clusters of atoms from the bombarded region. Some of the atoms and atomic clusters are ejected as ions, called secondary ions. The secondary ions are subsequently accelerated into a mass spectrometer, where they are separated according to their mass-to-charge ratio and counted. The relative quantities of the measured secondary ions are converted to concentrations, by comparison with standards, to reveal the composition and trace impurity content of the specimen as a function of sputtering dme (depth). 

Sputtered Neutral Mass Spectrometry (SNMS) is the mass spectrometric analysis of sputtered atoms ejected from a solid surface by energetic ion bombardment. The sputtered atoms are ionized for mass spectrometric analysis by a mechanism separate from the sputtering atomization. As such, SNMS is complementary to Secondary Ion Mass Spectrometry (SIMS), which is the mass spectrometric analysis of sputtered ions, as distinct from sputtered atoms. The forte of SNMS analysis, compared to SIMS, is the accurate measurement of concentration depth profiles through chemically complex thin-film structures, including interfaces, with excellent depth resolution and to trace concentration levels. Genetically both SALI and GDMS are specific examples of SNMS. In this article we concentrate on post ionization only by electron impact. 

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