Articles
Vacuum Conveying For Tabletting Operations
August 6, 2007
Click Here To Download:•Application Note: Vacuum Conveying For Tabletting Operations
Background
Pneumatic conveying by vacuum
is quickly becoming one of the
most popular means of transport
for a variety of pharmaceutical
products. The use of either dense
or dilute phase vacuum transfer
can be applied to tabletting
operations such as the loading of
blenders, sifters, mills, capsule
fillers, tablet presses, and even tablet
and capsule handling without
damage to the finished product.
Dilute or Dense Phase?
Dilute phase conveying should be used with materials where segregation or attrition in the conveying line is not a concern. Comparitive gas/air velocities in a 3" pipe for dilute phase can range from 15 m/sec (3000 ft/min) up to 35 m/ sec (7000 ft/min). In dense phase operations, a reduced gas velocity range of 0.04 m/sec (80 ft/min) to only 9 m/sec (1700 ft/min) is utilized.
In most applications the gas is air; however, in the pharmaceutical industry, nitrogen is also widely used due to its inerting capabilities as well as the natural purity of the gas. The lower gas velocity used with dense phase conveying means the force exerted on the conveyed powder or granulate is much gentler. This gentle action also reduces the segregation often experienced with the more aggressive dilute phase operation.
Click Here To Download:•Application Note: Vacuum Conveying For Tabletting Operations
