Knocking down a concrete building usually takes brute force: Wrecking balls, huge excavators, or explosives rip apart walls while fire hoses spray water to keep the clouds of dust down. It’s an energy-intensive process, and after everything’s been torn apart, the concrete often ends up in a landfill or has to be trucked to a recycling facility. But a new concrete-erasing robot may eventually transform the messy business of demolition.
The ERO (short for "erosion") robot uses water to disassemble concrete and then sucks all of the separate components—cement, sand, and aggregate—neatly into different packages for reuse. "High-pressure water jets attack the micro cracks on the concrete surface, making it come apart," explains Omer Haciomeroglu, a student at Umeå Institute of Design in Sweden, who designed the robot last year. "It leaves the metal rebar inside naked and ready for reuse."
Since all the materials can be separated on site, the process avoids the costs and pollution of transporting heavy chunks of concrete and metal to recycling plants. Haciomeroglu envisions a new business model: When a building comes down, the demolition crew could set up a station nearby to turn the materials into new prefab building blocks, and then those could be sold directly to someone constructing a new building in the neighborhood.
"You can reutilize it within the city, without actually sending it far away to be crushed down, separated, and all of that mess," he says.
The machine runs on electric power, and actually recollects some of its own energy; as the vacuum sucks recycled concrete down a tube, the moving air generates electricity that the system can reuse.
The design is just a concept for now, though Haciomeroglu plans to built it and is already in conversations with manufacturers. Once he has a partnership with a company, the next step will be building and testing a prototype, which may take two or three years.
There's already plenty of demand. More concrete is manufactured than any other material on the planet. And since it tends to last only 40 to 60 years, there's quite a bit of old concrete coming down all the time; in the U.S. alone, over 300 million metric tons of concrete waste are created each year.
One of the biggest markets for the ERO may be China, where buildings are being razed at an unprecedented rate to make way for new construction, and only 5% of building waste is currently reused.
"In Asia, there's a lot of potential," Haciomeroglu says. "But this can be used everywhere. Even in Europe, they’re demolishing a lot of concrete buildings and they don’t know how to recycle, so they’re wasting that valuable material. ERO is a smarter way to do it. I wanted to design a role-model product that would show the industry how to approach demolition in a different and provocative way."