The Process

CO2 dry ice cleaning is rapidly becoming the preferred method of cleaning among the industrial, commercial, utility, and environmental sectors.

CO2 Dry Ice Cleaning

Benefits:

Online cleaning of various types of equipment eliminates the need of disassembly and shutdown, allowing operations to continue.

How does it work?

Compressed air shoots the dry ice pellets out of a nozzle at -109.3 degree F or -78 degree C, somewhat like sandblasting or high pressure water or steam blasting, but with superior results.
The dry ice “blasting” against the material to be removed causes it to shrink and loose adhesion from its subsurface.
Additionally when some of the dry ice penetrates through the material to be removed, it comes in contact with the underlying surface. The warmer subsurface causes the dry ice to convert back into carbon dioxide gas. This gas expands up to 800 times its volume and expands behind the material, speeding up its removal.

The cleaning action of dry ice blasting is due to three factors:

KINETIC ENERGY: Compressed air propels the dry ice particles up to supersonic speeds. Though light in weight, they puncture the contaminate and chip away at it, thereby opening the surface of the contaminate.

THERMAL DIFFERENTIALS: An immediate and localized cold shock to the contaminate versus a substrate (surface) which cools down much less. This action promotes a contact break between contaminate and substrate.

SUBLIMATION: As the dry ice sublimes (becomes a gas) on impact, it increases up to 800 times its volume from solid to vapor, when it enters the cracks within the contaminate. This gas expansion, breaking up the contaminate from within, is the major factor responsible for the Dry Ice cleaning effect.

Dry Ice Blasting Sublimation

Instead of using hard abrasive media to grind on a surface, often causing damage, dry ice blasting uses soft dry ice, accelerated to supersonic speeds, creating mini-explosions on the surface to lift the undesirable item off the underlying substrate.

Dry Ice vs. Other Methods

Dry Ice Cleaning Comparison:

Blasting Cleaning Technique	Waste?	Abrasive?	Toxic?	Electrically Conductive?	Performance
Dry Ice	No	No	No	No	Excellent
Sand	Yes	Yes	No	No	OK
Glass Beads	Yes	Yes	No*	No	OK
Walnut Shells	Yes	Yes	No*	No	Limited
Steam	No	No	No*	Yes	Poor
Solvents	Yes	No	Yes	Yes	Limited

* Each of these blasting materials becomes contaminated upon contact if used to clean hazardous objects. When this happens, these materials are then classified as toxic waste requiring safe disposal.

Advantages of Dry Ice Cleaning vs Traditional Methods:

Issue	Traditional	Dry Ice Blasting
Equipment Downtime	Relocated for cleaning Disassembly/reassembly Drying time required	Equipment can be cleaned in place Dry process - equipment can restart immediately after cleaning
Hazardous Waste	Cleaner becomes and treated as as secondary contaminant	No additional contaminates Dry ice sublimates (becomes a gas) with contact with the target surface
Labour Hours	Intensive hand scrubbing Lengthy cleaning and follow-up cleaning	Dramatically reduced - often completed in a quarter of time or better
Quality of Cleaning	Poor to average	Excellent
Potential Equipment Damage	Grit abrasions Grit contamination Movement of equipment to and from cleaning area	No equipment damage Preventative maintenance very realistic as labor hours are much less
Safety	Health threats from solvents Water-based cleaning pose hazards around electrical equipment Threats to the environment	Standard safety precautions Dry process is safe around electrical equipment
Cost	Cleaner becomes additional hazardous waste Expensive Solvents Additional labor	Minimal cost of dry ice