Dry ice is a fascinating substance widely used for cooling, shipping perishable goods, and industrial applications like dry ice blasting. But what makes dry ice solid blocks and dry ice pellets unique is that they don’t melt like regular ice—they sublimate. This process raises important questions: what is sublimation, how is dry ice made, and why does dry ice sublimate? Let’s explore the science behind this phenomenon and the factors that affect its sublimation rate.
What Is Sublimation?
Sublimation is a process in which a solid turns directly into gas without passing through a liquid phase. This happens when the atmospheric pressure and temperature conditions allow a substance to skip the liquid state entirely. Unlike water ice, which melts into liquid before evaporating, dry ice sublimates, meaning it transforms directly from solid carbon dioxide (CO₂) into CO₂ gas.
How Is Dry Ice Made?
The production of dry ice involves several key steps:
- Capturing Carbon Dioxide Gas – CO₂ is collected as a byproduct from industrial processes like fermentation or ammonia production.
- Compressing and Cooling the Gas – The gas is pressurized and cooled until it liquefies.
- Expanding the Liquid CO₂ – When rapidly expanded, the liquid CO₂ forms a snow-like solid.
- Pressing Into Blocks or Pellets – This solid CO₂ is then compacted into dry ice solid blocks or shaped into dry ice pellets, making it easy to handle and transport.
Why Does Dry Ice Sublimate?
Unlike water ice, which requires heat to melt into a liquid, dry ice sublimates due to the difference in its chemical properties. At atmospheric pressure, carbon dioxide does not have a liquid phase, so when exposed to normal temperatures, it instantly converts from a solid to a gas.
Factors that contribute to dry ice sublimation include:
- Temperature: Higher temperatures accelerate sublimation, while lower temperatures slow it down.
- Airflow: Increased ventilation causes dry ice to sublimate faster as more CO₂ gas escapes.
- Surface Area: Dry ice pellets sublimate faster than dry ice solid blocks because of their increased surface exposure.
- Container Insulation: Dry ice coolers and dry ice containers help reduce sublimation by providing insulation.
What Is the Rate of Dry Ice Sublimation?
On average, dry ice sublimates at a rate of 5-10 pounds per 24 hours, depending on storage conditions. The rate can increase in warmer environments or if dry ice is stored in non-insulated containers. Using high-quality dry ice coolers can significantly slow down this process.
How to Slow Down Dry Ice Sublimation
If you need dry ice for delivery service, airport dry ice packaging service, or long-term storage, follow these tips to preserve it longer:
- Use Proper Insulation: Store in dry ice containers with thick walls.
- Limit Air Exposure: Reduce openings to minimize airflow.
- Keep in a Cold Place: Avoid placing dry ice in direct sunlight or warm areas.
- Use Larger Blocks: Dry ice solid blocks last longer than dry ice pellets due to their lower surface area.
Safe Handling of Dry Ice
Since dry ice sublimates into CO₂ gas, it must be handled safely:
- Use Dry Ice Gloves: Direct skin contact can cause frostbite.
- Ensure Proper Ventilation: Never store dry ice in airtight containers to prevent pressure buildup.
- Follow Safety Guides: Learn about how long dry ice lasts, how to travel in a car with dry ice, and other important handling tips.
Where to Buy High-Quality Dry Ice
At SubZero Dry Ice, we provide premium dry ice solid blocks, dry ice for blasting, and dry ice pellets at the lowest price. Our online ordering system for commercial buyers makes it easy to place bulk orders, while our dry ice delivery service ensures reliable supply.
Conclusion
Understanding what sublimation is, how dry ice is made, and why dry ice sublimates helps you use it more efficiently. The rate of sublimation depends on factors like temperature, airflow, and insulation, but with proper storage and handling, you can extend its usability. Whether you need dry ice coolers, dry ice delivery service, or dry ice for blasting, SubZero Dry Ice is your trusted supplier for the best quality at the best price.
Order from our online ordering system today and experience superior dry ice solutions!