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 firstname.lastname@example.org. 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.