Swedish researchers have developed a process that can turn contaminated sediment in shipping ports into a cement-like substance that is safe for building. The researchers were looking for new options for disposing of contaminated sediment — during port construction it is often required that the sediment be removed. Previously it was dredged and then dumped on land or out at sea, but this new process removes the sediment from the port, mixes it on-site with an adhesive material and creates cement like blocks that are sturdy, long lasting and can be used for building new structures.
The project, called STABCON, was spearheaded by EUREKA — a European organization that uses new technology to advance industry — and Merox, a subsidiary of Swedish steelmaker Svenskt Stål AB, who provided the mixing solution. In ports around the world, decades of chemicals spewed into the water by thousands of ships and barges are locked in the sediment that rests at the bottom of the port. Dredging of contaminated soil is often required before construction can begin because the construction process itself can disturb the contaminated sediment. If the sediment is disturbed but not contained it can leak into surrounding waters and cause larger environmental problems. Disposing of the sediment in an environmentally friendly way has long been a question, project managers have to find a place for the highly contaminated soil to go.
This new process takes what was once treated as toxic and uses it as the recycled building blocks of the ports future. Göran Holm, R&D director of the Swedish Geotechnical Institute, one of the project partners, explained that this new process, “reduces the demand for natural resources, such as blasted rock; and by treating the sediments in situ and using them in port areas, the need for transport is reduced, along with the associated health risks.” Researchers tested the integrity of their new building blocks prior to construction and found them structurally sound and able to stand up to the long term pressures of building materials.
WHY THIS MATTERS
Not only does this new method remove toxic sludge from the oceans, it also transforms it into a useful building material.
Via Science Daily