Siemens steels CO2

The steel industry is a huge contributor to greenhouse gases. One of steel’s essential ingredients is coke. Bake it with limestone and iron ore and out comes steel, to cut a long story short. Coke is a converted version of coal, and we all know the connection between coal and CO2.

To its credit, the steel industry has a number of measures underway to reduce its carbon footprint. Its holy grail is to eventually remove coke from the process. But that could take decades.

Meanwhile, one of steel’s environmental attributes is that it is highly recyclable. About 30 percent of the world’s steel comes from scrap.That’s still not a purely green process. A lot of recycled steel gets cooked in an electric arc furnace, but the eco impact is less than making it anew.

To help illustrate the point, German industrial giant Siemens recently set a sharp-eyed photographer to its railway factory hall in Vienna. The result was the industrial artistry above and below. The skeletons form the frame to a locomotive that pulls Austria’s high-speed trains, called the Railjet.

“In contrast to light rail vehicles, locomotives of large passenger trains need to weigh a great deal in order to be able to pull the heavy train," Siemens states. "That makes it that much more important for the valuable material to be reused at a later point in time. The skeleton of the Railjet of the Austrian Federal Railway – shown here in the Vienna factory hall – is made completely of steel that can be recycled into components for new trains after the interior furnishings are removed.”

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