Cleaning with dry ice: Fumes, waste disappear with cryogenic blasting
By Noelle Edwards
Mike Coleman runs a business doing powerful industrial cleaning. And the byproduct disappears into thin air.
The technique is called cryogenic blasting, and it’s basically sandblasting, except without the sand. Instead, it uses dry ice pellets.
The advantage, Coleman said, is that the process is clean. It produces no fumes, no residue, no health hazard and no waste.
His business is called Enviro-Tech, and he started it about a year ago. Before that, he was a salesman in Fortune 500 business. He got tired of the pace and pressure of the corporate world, and a friend suggested he get into the cryogenic blasting business.
It was a good time for it, he said, since the trend now is toward green, or environmental, initiatives.
His wife, who is a vice president at Bank of America, was completely supportive, he said.
“It’s a good feeling when you have support at home,” he said.
He invested about $150,000 he and his wife had saved to buy the equipment and get started.
For each job, he starts with a cooler full of ice pellets. Bit by bit, those pellets go into a machine that adds cold air to blast the pellets through a hose, out a nozzle and onto the thing being cleaned.
The pellets hit the dirty or covered surface at an intense speed, penetrating and blasting off the dirt, the paint, the rubber, the vinyl, whatever is standing in the way of a clean and fresh surface. Coleman said the underlying surface isn’t harmed.
And the dry ice evaporates instantaneously with only a puff of vapor.
Depending on what he is cleaning, he can adjust the pressure by changing the nozzle. Nozzles designed for gentler cleaning fragment the pellets of dry ice and so deliver a less forceful blast.
The pellets, which he gets from an Atlanta company, are 109.3 degrees below zero. And Coleman doesn’t even wear full gloves, just grips that leave his fingers exposed.
He has scars from burns he’s gotten from the ice, but the ice is safe to handle or be exposed to for brief periods of time.
It’s when the ice sits on his skin for longer than several seconds, such as when he was cleaning the fountain at First Presbyterian Church in Salisbury and a bunch of ice fell into his boot, that it burns ó just like fire or extreme heat.
The ice can also freeze up his equipment if he isn’t careful. Once he puts a batch of ice in the machine that mixes the ice and cold air, he has to keep working without stopping, or his machine is dead in the water. Or rather the water is dead in the machine.
But his equipment is the only equipment dry ice blasting could damage.
In fact, he said, one advantage of this cleaning technique is that it is safe for machinery, even electrical engines, while blasting with water would be ruinous.
He can also clean things such as the church fountain and walls covered in paint that if cleaned with water would wash toxic particles down a drain into the sewer.
He has used cryogenic blasting to clean dangerous mold from people’s homes. He got his mold remediation license because he said the dry ice technique works well for the cleaning part, and the low temperatures of the ice kill the mold for good.
On the other end of the size scale, he just finished putting together a quote for a 22-story building in downtown Charlotte. He said jobs he’s done have taken as few as eight hours or as many as three months.
He said a lot of cities and counties can get federal money and grants for green initiatives, and cryogenic cleaning is one way they could spend that money.
Most recently, he put together a quote for the city of Concord to clean street signs so the city doesn’t have to replace them all.
He doesn’t just mean cleaning the dirt off. He plans to blast the color and type right off the aluminum.
He said the dry ice process can remove the vinyl layer of print and save the aluminum sheet underneath, saving the city the expense and waste of producing more aluminum.
The cost of his service is similar to sandblasting, he said.
For more information, go to www.ice-blasters.com or call 980-521-6972.