Is liquid nitrogen evaporating quickly or not? Guide

Is liquid nitrogen evaporating quickly or not? Guide you to understand static evaporation rate
During the storage process of liquid nitrogen, the evaporation rate is one of the most concerning issues for users. Static Evaporation Rate is the core indicator for measuring the insulation performance of liquid nitrogen tanks. By understanding this parameter, you can accurately predict the storage time of liquid nitrogen.

1、 What is static evaporation rate?
Static evaporation rate refers to the natural evaporation rate of liquid nitrogen per unit time when the liquid nitrogen tank is in a static state. Usually expressed as "liters/day" or "percentage/day". For example, a 10L liquid nitrogen tank labeled as "0.2L/day" means that about 0.2 liters of liquid nitrogen naturally evaporates every day.

2、 Three major factors affecting evaporation rate
Vacuum insulation performance
High quality liquid nitrogen tank adopts a double-layer vacuum structure
The vacuum degree needs to be maintained at 10-3Pa or above
Leakage is the main cause of accelerated evaporation

Neck canal design
For every 1cm increase in cervical canal diameter, evaporation increases by 15%
Modern narrow neck design can reduce evaporation by 30%
Special anti backflow structure can further reduce volatilization

ambient temperature
The benchmark value for evaporation at 25 ℃ is 100%
For every 10 ℃ increase in temperature, the evaporation rate increases by 20-25%
• It is recommended to store in a cool and ventilated place

3、 Actual application conversion
Taking a 50L liquid nitrogen tank as an example:
If the daily evaporation rate is marked as 0.5%
• Daily volatilization: 50L x 0.5%=0.25L
Theoretical shelf life after filling with liquid nitrogen: 50L ÷ 0.25L/day=200 days

4、 Purchase suggestions
Prioritize products with an evaporation rate of ≤ 0.3%/day

Pay attention to the vacuum shelf life (high-quality products ≥ 5 years)

Regularly check whether the surface of the tank is frosted (abnormal frosting indicates vacuum failure)

Actual test data shows that modern high-quality liquid nitrogen tanks can control the static evaporation rate at 0.1% -0.2%/day through multi-layer insulation materials and vacuum mirror reflection technology. This means that a 30L liquid nitrogen tank, when filled to capacity at 25 ℃, can be maintained without refilling for 150-300 days. Choosing products with low evaporation rates can save over 30% of liquid nitrogen consumption costs through long-term use.