March 5, 2007 4:00 AM PST
Eco-friendly toxic cleanup is a blast
Broken windows dot some of the older buildings, which date back to the 1880s. Scraped-up forklifts and stevedores flip cargo around. Chemical odors waft through the air. And nearly everywhere the ground is strewn with traces and piles of fine black grit, the remnants from various sandblasting operations needed to clean the hulls of the many ships passing through the facility.
Eliminating the grit--chock full of arsenic, toxins, paint solids and heavy metals--is a primary goal at the facility. BAE Systems is using a robot from Ecosphere Technologies that blasts ship hulls with water coming out at 42,000 pounds or more of pressure per square inch. The pressure is so high that the water heats the metal of the hull to 185 degrees Fahrenheit, sterilizing the surface and removing corrosive salts.
The water and paint sludge generated by the M-3500 robot then get sucked into a contained disposal unit. Removing 82,000 square feet of paint results in about 10,000 gallons of treatable water and 1,800 gallons of paint solids that have to go to the hazardous waste treatment center, according to Ira Maybaum, general manger of BAE Systems' San Francisco facility.
Traditional grit blasting, by contrast, would result in 500 to 600 tons of contaminated grit, some recovered, some scattered around the shipyard and onto vessels in for repair.
"You just can't take that to a landfill. It's a dramatic difference," Maybaum said. "Grit is effective for taking paint off, but it's not the most environmentally friendly thing."
Environmental hazards may not be the most glamorous focus of the clean-tech market, but it's a big opportunity, asserts Dennis McGuire, CEO of Stuart, Fla.-based Ecosphere, which both creates high-pressure water machines and licenses patents.
"There are 90,000 ships in the world, and every year they come out of the water to get cleaned," he said. On average, each ship has approximately 200,000 square feet of hull surface that needs to be scrubbed and/or repainted, he added.
Robot cleans off cargo ships
Experimental method is more eco-friendly than traditional blasting.
Ecosphere's evolution into a green company in some ways happened by chance. Nearly two decades ago, McGuire developed a high-pressure hose to remove paint from ship hulls. It worked well, but the Environmental Protection Agency had a major problem with it: the sludge dumped straight into the water.
"Marine paint is some of the most toxic stuff in the world," he said. "It contains arsenic, lead. It kills marine life on contact."
To that end, McGuire and his team developed the vacuum system to capture sludge. The company also optimized the nozzle, an array of jets "that rotates like a Cuisinart," says McGuire.
Right now, Ecosphere is a fairly small operation: revenue in the quarter ending last September came to about $1 million. Demand, though, is being driven by tighter environmental regulations and cost. A lone operator with a joystick can scrape the hull of a ship in about 7 to 10 days with the M-3500, said Maybaum. Sandblasting the same ship would require upwards of 10 employees and take longer.
Cleanup is also a necessary part of sandblasting. With transport and cargo ships, the task involves disposing of the tons of grit. With cruise ships, it's more complex. The grit is not contained and thus can seep into the cabins and other rooms on the ship. Cruise lines have begun to demand robotic cleaners, Maybaum said.
The overall potential cost savings vary, depending on the structure of the deal and local circumstances. BAE Systems has signed a five-year deal with Ecosphere, which brings in the robot as a service. In the first trial with BAE Systems, the M-3500 cleaned the hull of the USNS Henry J. Kaiser in less than two weeks, and Ecosphere charged BAE $111,000. Meanwhile, dry dock operators in Singapore are buying the robots outright.
In case of emergency...
In addition to the ship cleaning technology, Ecosphere has also created an emergency water purification unit that mounts on a tractor trailer. After Hurricane Katrina, Ecosphere and Pierce Manufacturing, its trucking partner, brought it to Waveland, Miss., where 2,500 people remained stranded.
"We pulled water from a contaminated fire plug for six weeks," McGuire said.
The system for purifying water in emergencies also relies on pressure. Water is forced through a series of filters and membranes to eliminate solids and bacteria. Additionally, ozone gets injected into the water to kill microorganisms; however, the ozone is kept away from the membranes so that it won't degrade them.
The mobile unit can churn out about 30 gallons of purified water per hour, and the purification system can operate on solar panels.
How clean does the water get? The Department of Homeland Security conducted tests with the system to see if it could filter water after a bioterrorism attack. The EPA has since verified it for use in the event of such an attack.
While the company has primarily designed the systems for emergencies, mobile and distributed water systems are expected to become increasingly popular. Residents in some of India's more densely populated urban centers now get their water by truck, the result of a crisis in the water and sewer system. General Electric is working with a chain of grocery stores to install water purification stalls. GE has also developed mobile water trucks.
Meanwhile, Ecosphere will continue to look for more things to blast.
"We're always experimenting with compressed water," he said.
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