Nitrogen gas plays an essential role in the pharmaceutical
industry, with a broad range of applications ranging from packaging to fire
suppression in an obviously volatile manufacturing environment. With recent
technological advancements, on-site nitrogen generation equipment can now
provide purity levels equal to that of liquid nitrogen, helping pharmaceutical
manufacturers lower costs without sacrificing quality or efficiency.

Moving from liquid delivery to on-site nitrogen generation
in the pharmaceutical industry can reduce costs between 40 percent and 80
percent, depending on current liquid nitrogen market prices. While bulk costs
for delivered liquid nitrogen can range from $0.35 per hundred cubic feet to
$1.50 per hundred cubic feet, the costs of delivery for nitrogen in cylinders
can jump as high as $3 per hundred cubic feet.

 

When calculating costs from a feed air compressor, and
considering energy costs at $.08 kW an hour, on-site nitrogen generation costs
drop to $0.21 per hundred cubic feet. After five years, typically when the
return on capital costs is realized, costs can drop by an additional 50
percent. When the return on investment for these capital expenditures needed
for on-site nitrogen generation (generators, air compressors, receivers, site preparation,
power and maintenance) are factored in, pharmaceutical manufacturers will see
day-to-day operational costs drop to about $0.11 per hundred cubic feet – the
cost of maintenance and energy.

Liquid nitrogen deliveries require that the gas be converted
to a liquid for truck transport. Upon arrival, the liquid must then be
converted back into a gas. This two-time transfer of states because of these
filling points – loading into the transport vehicle at the nitrogen facility
and unloading again at the pharmaceutical production facility – creates
avoidable product waste, not to mention additional charges for delivery.

Nitrogen gas, when delivered to a pharmaceutical
manufacturing facility, must also be stored on-site prior to use, also creating
additional unnecessary waste. Once inside a cooled tank, the loss is often an
automatic 10 percent of the delivery volume. And, even with a good vacuum, the
tank will lose a minimum of .4 percent of volume daily if internal pressures
are allowed to build because the gas remains sedentary. Purging or releasing
tank pressure only contributes additional waste as well.

To help outline projected costs and determine the potential
savings when shifting to on-site nitrogen generation, equipment providers like
Atlas Copco can work with facility managers to develop a spreadsheet outlining
cost comparisons. This provides a framework of all outlays associated with the
process – liquid nitrogen costs per hundred cubic feet, tank rental fees,
delivery charges, hazmat charges and other miscellaneous costs.

And consider this: while generating liquid nitrogen requires
a tremendous amount of energy, about 80 percent of nitrogen end uses require it
as a gas and not a liquid. The primary reason nitrogen is liquefied is for ease
of transportation, so shifting to on-site nitrogen generation helps reduce
energy costs and lower emissions associated with the facility’s daily
operation. Factor in diesel fuel emissions from vehicular traffic needed for
delivery of liquid nitrogen, and these benefits compound while increasing the
environmental impact on the surrounding communities.

While liquid nitrogen delivery channels have traditionally
provided greater product purity – an essential element in pharmaceutical
production – over on-site generation, technology has helped boost on-site
nitrogen generation purity to close this gap. As a result, higher purities in
on-site nitrogen generation are now comparable to the liquid product and, with
proper instrumentation,

can be measured to ppt levels of oxygen concentration.
Ninety-nine percent of all industry applications can be met within the 10 to
five ppm levels that can be achieved with a pressure swing adsorption generator.

Shifting to on-site nitrogen generation capabilities is just
one way that pharmaceutical manufacturing facilities can achieve significant
cost savings, with the added benefit of a lower carbon footprint to help lead
the way as an environmental steward in the community.

 

For a free copy of Atlas Copco’s 136-page Compressed Air
Manual 7th Edition, please send an e-mail to paul.humphreys@us.atlascopco.com.
Put “Manual – PharmPro” in the subject line and
provide your delivery address in the body of the e-mail, and Atlas Copco will
send you a complimentary copy.