Many of today’s freeze dryers incorporate yesterday’s vacuum technology where you are likely to experience lost production due to downtime for service, maintenance, or slowed cycle time. Today’s vacuum technology can help reduce operating and maintenance costs with little to no downtime.

What are the challenges of using a rotary pump for freeze drying?

In a word, moisture. In any freeze dryer, the condenser traps are imperfect and occasionally allow water vapor to get to the vacuum pumps where it condenses with oil. This reduces the pumping capacity of the pump resulting in longer cycle times. Water in pump oil shortens oil life considerably resulting in more frequent maintenance needed for the pump. In addition, water in pump oil causes oil to breakdown, lose viscosity and cause premature pump failure.

Other challenges faced with oil sealed rotary vane pumps for this application include:

• High maintenance cost, 20-40 liters of oil each occurrence, each pump
• Exhaust filters - up to $1000 per pump
• Oil disposal cost
• Pump rebuild 1-3 years, rust, heavy wear
• High energy cost

What makes dry screw vacuum pumps a better option for freeze drying?

Dry screw vacuum pumps are particularly well suited for freeze drying foodstuff systems because they don’t require oil to operate. Dry pumps achieve the required vacuum levels without operating fluids, significantly reducing maintenance costs and downtime.

Other advantages for switching to dry:

• Increase in throughput on existing equipment by eliminating pump inefficiencies due to water vapor carry over
• Easily manage organic acid carry over - Dry pump can be cleaned on site
• Eliminate oil contamination in product
• Reduce maintenance costs by at least 50%
• Cleaner work area due to no oil mist from exhaust
• Reduce carbon footprint

Want more up-time and production efficiency? Check out Leybold’s FREE on-demand webinar “Freeze Drying and Vacuum”

Need to know more about choosing a dry vacuum solution? Contact sales@intlvac.ca or 1.800.959.5517 and speak to one of our vacuum specialists!