Vacuum producing equipment Control

States or Australia. In some cases, pot stills, arranged in cascade, are still used. The more sophisticated plants employ one or more carbon steel or cast-iron vessels heated electrically and equipped with temperature controls for both the bulk Hquid and the vessel walls. Contact time is usually 6—10 h. However, modem pitches are vacuum-distilled, producing no secondary quinoline insolubles, to improve the rheological properties. 

This process has found major application in the wine industry to control the alcohol content of wines (i.e. remove alcohol to the desired level). Wine is initially passed through the equipment at temperatures and pressures that primarily strip aroma components. The dearomatised wine is then passed a second time through the equipment at higher temperatures and vacuum to strip the desired amount of alcohol from the wine. The initially captured aroma fraction can then be added back to the reduced alcohol wine to produce the desired... 

The Mizushima Oil Refinery of Japan Energy Corporation first implemented a high conversion operation of vacuum residue, versus a constant desulfurization operation, in the commercial residue hydrodesulfurization unit equipped with fixed-bed reactors, to produce more middle distillates as well as fuel oil with lower viscosity. The catalysts will be replaced when the sulfur content in the product oil reaches the allowable limit. Since we have believed that an increase in the residue conversion decreases the catalyst activity by coke deposition, we have been interested in controlling the coke deactivation to maximize the residue conversion during a scheduled operating period. 

Power amplification is produced by four tetrode vacuum tubes connected in pushpull-parallel as a Class AB2 amplifier. Control of the master audio oscillator signal amplitude is provided by a potentiometer on the master control panel. The output voltage of the equipment may be reduced to zero even when full voltage is applied to the plates of the power tetrodes. 

In vacuum metallizing, which also requires a major capital investment in equipment, a metallic film, usually aluminum, is deposited onto a plastic by condensation from vapor under high vacuum. By rotating parts during application, a controlled film thickness can be obtained producing high levels of attenuation with layers as thin as 4—6 microns. 

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