Storing liquid nitrogen
A clean supply of liquid nitrogen is essential to trouble free operation of liquid nitrogen cryosurgical treatment units. To ensure a clean nitrogen supply, we advise to completely empty the storage tank (dewar) 3 - 4 times per year prior to refilling.
If necessary, water from ice crystals remaining inside the tank can be dried out by creating air circulation (e.g. using a vacuum cleaner for approx. 15 min.).
To prevent ice and other particles in the tank from entering the treatment unit when filling, always use a withdrawal tube equipped with a filter.
For a demonstration on how the withdrawal tube works check the video below: