By-products from steel works include slag, dust, sludge and other waste materials. 100% of the slag is recycled as the material for cement and the aggregate for road and engineering works, while dust and sludge and other by-products are recycled as raw material for steel and the by-material for steel process or used as the material for cement and fertilizer.
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In 2007, 98.7% out of 2,0680,000 tons of the total by-products resulted from Pohang Works and Gwangyang Works are being recycled, and the rest of them is either incinerated or buried in the ground. Also, in order for a higher value-added application of slag, 82% of products in 2007 have produced by water-soluble slag. To solve the short supply of lump ore and maintain demands of slag for steelworks, the complex slug is expanded to be utilized as the roadbed material.