Desiccators are a safe means of storage for highly-sensitive samples or materials. A continuous purge of nitrogen or other process gas creates the positive pressure environment that’s conducive to a contamination- and humidity-free desiccator. But, what if a purging system allowed your desiccator to do more than just store parts? What if it also automatically reduced nitrogen costs and prevented overpressure? Terra’s Dual Purge system does exactly that—and when it’s paired with the NitroWatch humidity control system, the relative humidity percent set-point is automatically monitored and maintained. Keep reading to find out how this dynamic duo has changed the way we use desiccators.
Why might my purging system be out of date?
许多净化系统使用大量的氮(or other process gases) in order to avoid build-up of moisture inside the desiccator, as well as infiltration of contaminants when the doors are opened. The small amount of process gas required to maintain low positive pressure is incapable of preventing influx air when the chamber is opened. Therefore, regardless of an open or closed desiccator door, the high gas level remains constant. While backflow may be prevented, this method not only wastes nitrogen when the door is closed, but also puts excess strain on the doors and seals due to the greater pressure levels.
Dual Purge and NitroWatch Control systems
What’s so different about the Dual Purge?
在下一个清除系统的选择过程中，重要的是要考虑氮费用，访问频率和湿度要求。使用双清除系统，在使用经济量的氮/工艺气体关闭门时，保持一致的低正压（约0.05英寸的水表）。当访问干燥器时，打开门上的开关传感器会激活高流量清除。氮气淹没了腔室，增加了内部气压，以最大程度地减少流入污染物和水分。
门被固定后，净化继续进行，以迫使进入腔室的任何水分。Terra干燥剂上的自动释放/出血（RB）阀可缓解过度压力和渗出水分的空气，从而降低了样品或干燥剂损坏的风险。一旦干燥器达到其前压力水平，气体流入就会降低到其经济维护状态。如果操作员怀疑水分污染，则可调节的时间延迟可提供手动气体流入控制，以延长高速清除的持续时间。同样，“低压”警报与流量计结合使用，可以听到和明显地通知人员，如果传入的气线被中断或断开连接。
Nitrowatch如何控制湿度？
Terra’s NitroWatch humidity controller functions with the Dual Purge system to provide another layer of control by automatically managing your desired relative humidity (RH) set-point. The RH is pre-programed to the required percent and a miniaturized sensor continuously monitors and displays the RH on a digital LED screen. If the humidity level rises above the set point, NitroWatch signals the Dual Purge to initiate nitrogen purge until conditions are restored. The sensor provides 2% RH accuracy (or better) over a 10% to 90% RH range, and doesn’t require calibration.
Conclusion
For a time-saving and economical approach to efficient dry storage, the Dual Purge paired with NitroWatch not only eliminates worker supervision over delicate materials in desiccator chambers, but is proven to save up to 78% in nitrogen expenses! Set-point can be established for applications requiring a specific level, and recovery time is shortened. Personnel can program the humidity control system and let the auto-purging operation do the rest.
Learn more about Terra’sdesiccator control systems.