Comparing energy costs for vacuum and pressure systems
When it comes to pneumatic conveying, either a vacuum or pressure conveying system will often work in the same application. Choosing one system over the other usually comes down to comparing their energy costs — the major factor in determining an operation's success or failure in today's competitive manufacturing environment.
In this month's column, Jack Hilbert and Paul Solt evaluate the energy costs for seven conveying system designs — some pressure and some vacuum — that have different line diameters but convey the same dry bulk material under identical conditions. Each system conveys the material over a 310-foot horizontal distance and 15-foot vertical distance at a pickup velocity of 4,000 fpm and a conveying capacity of 700 lb/min.