Dry Ice and Soda info.
Dry Ice Blasting explained:
The dry ice blasting process consists of propelling dry ice (CO2) particles at supersonic speeds which impact and clean the surface of the object being blasted. The particles are accelerated by compressed air, just as with other blasting methods. Overall, there are three steps involved in dry ice blasting.
During blasting, dry ice pellets are propelled out of the blasting gun at supersonic speed and impact the surface. The energy transfer knocks off the contaminant without abrasion. The force of this impact is the primary means of cleaning.
The cold temperature during dry ice blasting of the dry ice pellets hitting the contaminant creates a micro-thermal shock (caused by the dry ice temperature of -109º F) between the surface contaminant and the substrate. Cracking and delamination of the contaminant occurs furthering the elimination process.
The final phase of dry ice blasting has the dry ice pellet explode on impact, and as the pellet warms it converts to a harmless CO2 gas which expands rapidly underneath the contaminant surface. This helps loosen the contaminant so it flakes off. The dry ice evaporates, leaving only the contaminant for disposal.
Decreased Downtime through Cleaning In-Place
Typical cleaning procedures require that equipment be disassembled and moved to an assigned area for proper cleaning. That is not the case with dry ice blasting. Equipment can be cleaned in-place and hot in most situations. Because of that, many time-consuming, labor-intensive steps which were required with other methods such as sand blasting can be eliminated. For example, equipment does not need cool down time, disassembly, relocation, reassembly and warm up time. This can shorten the downtime for cleaning equipment from days down to hours.
Faster and More Thorough Cleaning
With dry ice blast cleaning, a superior clean can be achieved while reducing hours when compared to scrubbing with abrasive pads or wire brushes. A tremendous labor savings is accomplished. In addition, the CO2 blasting method cleans in crevices that can't be reached by hand. As a result, equipment runs more efficiently and potential leaks are revealed possibly preventing major system failures.
Less Equipment Damage
Dry ice blasting often eliminates equipment damage. Cleaning methods such as sandblasting leave an aggressive and abrasive effect on the surface. They can actually remove part of the surface, changing the surface structure considerably. Dry ice is non-abrasive to surfaces and does not change a surface's structure. It lifts the contaminants away. Second, because equipment can now be cleaned in place, potential damage from moving equipment to and from a dedicated cleaning area is also eliminated.
Reduction or Elimination of Solvents
Dry ice blasting uses no solvents, but instead uses harmless CO2 pellets. This can be a critical need for certain companies in order to comply with environmental regulations or to improve worker safety. There are no issues pertaining to toxicity with CO2 blasting.
Reduced Waste Disposal
With other cleaning methods, whether it be with solvents, sand blasting or some other means, the cleaning agent becomes a secondary contaminant and must be disposed of as toxic waste along with the primary contaminant. However, with dry ice blast cleaning because the CO2 pellet vaporizes upon contact, the only waste created is the contaminant itself. This alone can result in significant waste reduction.
Dry ice blasting pellets are non-toxic, non-hazardous creating advantages to the environment, your employees, and production facility. There is no secondary waste associated with dry ice blasting. The procedure is safe for workers, does not damage equipment, does not contaminate end products and is environmentally friendly.
Why Choose Soda Blasting?
Cleaning & De-Coating in One Step
Standard abrasive blasting is a dirty process, often loading and even embedding the surface with contaminants (grease, oil, tar & abrasive particles) in the process of removing the coating. Recycled abrasives compound this problem by loading increasing amounts of contaminants into the substrate. Pure sodium bicarbonate blast media effectively de-coats and cleans the substrate in one step; producing a level of cleanliness not seen with most processes. The media is not reusable thus eliminating the issue of blasting with re-used media. Coating adhesion relies heavily on surface cleanliness and a surface profile has been used to offset this lack of cleanliness.
Unique Cutting Action
Sodium bicarbonate blast media offers the unique properties of sodium bicarbonate, the primary ingredient. The softness (Mohs hardness scale of 2.4) and friable nature of this crystal produces a unique cutting action with little or no effect on most substrates. For example, thick coatings can be removed from glass without any etching effect. With proper care, delicate substrates can be cleaned without damage.
No Pre-Cleaning Required
For projects where the coating is covered with grease, carbon, salt or other contaminates, the more traditional methods require the coating to be fully cleaned before blasting. This is required so that the contaminants on the surface of the coating not be driven through the coating and into the surface of the substrate, causing future coating failure.
No Need to Re-Profile Steel
Sodium bicarbonate blast media will not profile steel. When an operator removes a coating from a metal surface, he or she exposes the existing anchor pattern under the coating. Unless corrosion has occurred, there is no need to re-profile the surface.
Reduced Solid Waste
Pure sodium bicarbonate blast media can be dissolved in fresh water. By dissolving the media and filtering out the contaminates, the solution can generally be discharged to public waste treatment systems or open waterways, with proper discharge permits. Waste volume is generally reduced to less than 5% of the original waste volume. With increasing landfill costs and liabilities, this advantage becomes more important every day.
Natural Rust Inhibitor
As long as Baking Soda is on a ferrous metal surface, rust will not form. For rust to form, free moisture and an acidic condition must exist. In most cases, free moisture combines with carbon dioxide in the atmosphere to form carbonic acid. This acid releases a free metal (ferrous) ion, which combines with oxygen (oxidizes) to form rust. Pure sodium bicarbonate blast media buffers the acids, prevents the release of free metal ions and prevents rust.
Reduced Clean-Up costs
Large grain or coarse sodium bicarbonate soda blast media performs roughly the same level of work (somewhat slower) as sand blasting while producing 1/5 to 1/7 of the total waste volume. Although media costs per square foot are higher, site clean up and residue disposal are significantly lower. Combine that with the lower consumption rates of the Soda Works Buster Blaster system. The net balance is that total cost per square foot are about the same for both approaches.
Benefits In Waste Disposal
In most non-hazardous applications, the residue from blasting with pure sodium bicarbonate blast media can be rinsed into sanitary drains or sewers, which flush the residue to a water treatment facility, greatly reducing the clean up time. Pure sodium bicarbonate is actually beneficial to waste water treatment systems. For industrial treatment systems, where chemical neutralization is a major cost in water treatment, pure sodium bicarbonate blast media can often save significant dollars in waste treatment.
Increased Worker Safety
The safety of sodium bicarbonate to workers is well understood, since it has been in use for some 160 years. The bicarbonate buffer system is the major extracellular buffer for the human body, thus sodium bicarbonate is part of the body's normal chemistry. Pure sodium bicarbonate blast media is not toxic via ingestion, inhalation or dermal contact, nor is it a skin or eye irritant as defined by EPA and OSHA. Any risk to workers is primarily the contaminate or coating removed during the blasting process.
The same odor absorbing effect seen in the refrigerator at home is present when blasting with sodium bicarbonate blast media. It not only removes the contaminates, it also reduces the unfriendly odors.This is a real benefit in fire restoration and mold remediation.
Replaces Dangerous Solvents
Sodium bicarbonate blast media when applied wet is an excellent de-greasing medium that eliminates the use of solvents in most cleaning processes. Sodium bicarbonate blast media does not "dissolve" or "emulsify" grease or oils, it simply coats them causing the grease or oil to release from the surface. It also eliminates the translocation of oil and grease.
Does Not Produce Sparks
Sodium bicarbonate blast media will not produce thermal sparks and is suitable for use in explosion proof areas; including refineries, chemical plants and grain elevators as long as proper grounding techniques are used to prevent a static charge build up.
Improved Crack Detection
When cleaning metal surfaces for crack detection, standard abrasive blasting tends to peen the crack closed or pack the crack with abrasive, making crack detection more difficult. Sodium bicarbonate blast media actually cleans out the crack, leaving it exposed and easy to see.
No Residue Problems In Small Passageways
Natrium products soda blast media is 100% pure sodium bicarbonate, additive free and water soluble. It can be used to clean critical engine components including those with small passageways. Once cleaned, the baking soda residue can be thoroughly rinsed off by dissolving in water. Traditional blast material are not water soluble and if left after cleaning, can pack into small passageways and possibly damage an engine while on operation
Reduce Surface Acids
As a strong buffer for acids and alkali's, sodium bicarbonate blast media eliminates acidic conditions on the surface of the substrate. For conditions with high acid levels, acid rain or boiler fly ash, blasting with sodium bicarbonate blast media will reduce coating failures
The Difference between Soda and Sand blasting.
On the left side fine sand is used.
Sand will leave a rough surface behind but better rust removal.
On the right side Soda is used.
Soda will leave a smooth surface behind but will only remove superficial rust.
If desired we can use a mix of Soda and Sand or any other media, blasting wet or dry.
With our Soda Blasting equipment, we can blast with finer sand than a regular machine, The sand on the left which we use is 0.1 till 0.5 mm while the sand on the right used in a regular machine is 0.5 till 1.2 mm. This makes a big difference in the roughness.
Why use Soda?
"After all," you might be thinking, "I just want to strip some paint/light surface rust/grease/bacteria/mold/smoke from this project."
To get a good idea of why soda blasting is so good, it might help to understand a bit about how the action of soda blasting is different from other types of blasting. To understand how it is different lets take a look at sand blasting.
We want to remove paint from a fender, let's look at a simplified version of the structure of what we are cleaning. There's not too much to it. You have the metal coated with a layer of paint. The paint is thin-thin, only 7 thousandths of an inch thick.
Let's pretend we are going to remove the paint by Sand Blasting. Think about it from the perspective of the paint. That's right we are going to project rocks that are 3 times larger than the thickness of the paint at the fender at a high velocity. The sand is denser than the paint too. The force of the impact smashes and chops through the paint. The sand is harder than the metal as well. Any of the impact force that was not dissipated by the paint is now whacking the metal. Remember this is a thick, steady stream of sand. There is a lot of sand battering the bare metal and the surface ends up pitted and rough. The metal is stripped bare with only a dusting of the pulverized sand covering it's scarred surface. Within hours, the ambient moisture in the air will begin to attack the metal and the process of oxidation (rust) will begin.
Now let's take a look at what happens when I strip the paint with Soda Blasting.
A crystal of our blast media is huge compared to the layer of paint. But sodium bicarbonate is much softer and less dense than sand but it is still a bit harder than the paint so it can penetrate the paint layer just a bit and this is when the magic happens. Baking soda has a property called "high friability" - do you remember that kid in your grade school class that would go all to pieces laughing any time someone made a joke about flatulence? Sodium bicarbonate is just like that. It loves to go to pieces, that's what friability is. The bicarbonate crystal gets a little into the paint and breaks up. But it doesn't just crumble, it explodes! All of the energy that was projecting the Soda at the paint is released outward and all of the bits and pieces of the crystal are carried along. ripping and shredding into the paint. But, still, the metal is harder than the soda. It isn't affected at all by that battle going on at it's surface. What else is harder than Sodium Bicarbonate? glass, plastic, chrome, rubber, gaskets. Let's face is, Sodium Bicarbonate is that hardest-working wimp you will ever have the pleasure to work with!
When it's all done and my fender is clean there is an additional benefit to soda blasting. The bare, smooth metal has a light dusting of Sodium Bicarbonate. The dust is alkaline. For rust to form there needs to be a slightly acidic pH. The alkalinity neutralizes any acidic component of the air and protects the metal! Pretty cool, huh? Soda Blasting has the same effect when cleaning off mold damage. Molds, and bacteria too, need an acidic environment to survive. When you soda blast you are creating a safe, sterile surface. Still - I'm not going to eat lunch off of my fender!
With my fender stripped of paint, I can now clean and remove any contaminates and paint it a new color. The dust from the soda blasting can be rinsed off, it will dissolve in water. If there are any bits stuck in crevasses, they too will dissolve and rinse away. If I had sand blasted, I would have to rinse and wipe and wipe and rinse. I would have to take extra care to make sure there was no grit left in any crevasses. Imagine all of that uncomfortable grit left over from sand blasting. little bits grinding into your floor, in the seams of your clothing, stuck between your teeth. When it comes to final clean up, Baking Soda being water soluble is a blessing. You can only get so much with a broom, being able to easily rinse away any remaining dust is a huge time saver!
Cleaning anything with soda blasting is a vastly superior process. You can easily remove carbon, grease, oils, gasket material, surface corrosion, paint and coatings from a variety of alloys, plastics and composites without substrate damage or distortion, and leave hard anodized coatings intact.
When you are soda blasting you are saving time by cleaning, degreasing and depainting all in one step. What better paint preparation could there be?