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Oxygen Free Drying Without the Need for Supplemental Nitrogen

The NITROdry resin dryer provides processors with a new, oxygen-free tool to avoid degradation of nylons, PBT, PLA and TPU’s that is the result of prolonged exposure to heat in the presence of oxygen


Video Transcription

Narrator: We’re back with Mark Hayne again. Novatec patented its compressed air dryers several years ago, and literally thousands have been sold since then but now there’s a new version based on nitrogen. Why don’t you explain why.

Mark: The one thing about most testing that is done and in the development of polymers is done with nitrogen. That often they roll them out into the plant after they roll them out into the plant that they find out that they have discoloration loss in resin properties and that’s because of oxidation that occurs in the polymer when it’s exposed to heat. So, what we’ve done here is we’ve taken the NovaDryer which is a proven piece of equipment it’s been around since about 2001 and we’ve changed the membrane that’s in the cabinet from a membrane that just removes the moisture from the air to a membrane that removes the oxygen, CO2, and water vapor from the air, making it inert gas which does not affect the polymer properties. As you do that, some of the discoloration that you would normally see, some of your nylons that would change from, like a pure white to almost yellowish, and it loses some of its attractiveness and also the properties as far as its ability to be flexible, which is kind of what you want with a nylon. Those polymers are not degraded with this dryer as you would normally see occurring with just an air type dryer

Narrator: So how are you making the nitrogen?

Mark: There’s a membrane in here. The membrane has a number of hollow fibers. The compressed air, and that’s all you need here, you only put compressed air there’s no need to bring in nitrogen to this system. There’s been other nitrogen dryers in the past and some of these dryers, they’re not so attractive because you’re constantly changing nitrogen cylinders, you’re bringing in dewars of nitrogen and when it’s released it changes the oxygen concentration in the air so the oxygen in the room has to be continuously monitored because you’re releasing a nitrogen rich environment into the air that the rest of the people are breathing. With this, all you do is you put compressed air on it, the membrane will separate with the hollow fiber into it’s two streams. Oxygen will go and just vent through the membrane and the nitrogen goes through the drying process and what’s released back into the environment is the same thing. Air in, air out. No contamination of the environment.

Narrator: That’s great. Now does this dryer feature the same energy saving patent as was on the original membrane NovaDryer?

Mark: It does and as a result of that we’re able to use about 1/3 of the energy and 1/3 of the compressed air that would be used by any system that doesn’t follow our patent.

Narrator: Last question Mark. What sizes are available in this series?

Mark: There’s a model 7, 25 and 50. Those are the amount of pounds an hour that can be processed of the polymer within the drying system. These are all available within the next few weeks through Novatec.

Narrator: Thanks Mark. If you need any more information visit