Angang to Cut Costs and Emissions with Expanded Slag Processing
07/11/2012 - China’s Anshan Iron & Steel (Angang) plans to invest heavily in slag processing this year, increasing capacity from under 1m tonnes/year currently to 5m tonnes/year by the end of the year by installing four new slag milling units supplied by Germany’s ThyssenKrupp Polysius.
China’s Anshan Iron & Steel (Angang) plans to invest heavily in slag processing this year, increasing capacity from under 1m tonnes/year currently to 5m tonnes/year by the end of the year by installing four new slag milling units supplied by Germany’s ThyssenKrupp Polysius.
This should help reduce input costs and increase revenues for the steelmaker, Su Xingwen of the Slag Development Co. of Ansteel told delegates to the China International Metal Recycling Conference in Beijing.
Angang can currently produce up to 160,000 tonnes/year of >95% Fe iron nuggets and 180,000 tonnes/year of 60% Fe iron oxide concentrates from its slag processing facilities, helping to reduce input costs. This operation generated RMB 1.02bn of revenue last year. The refined iron nuggets are produced using one of Angang’s first patented technologies and can be used directly in the oxygen converter.
Once valuable minerals have been extracted, steel slag tailings can be ground to a powder and sold to cement and concrete producers. Angang produced 1.3m tonnes of tailings when it produced 16m tonnes of steel in 2009. By 2015, when it expects to produce 60m tonnes of steel, it aims to produce 4m tonnes of tailings.
In theory, capturing the 6 trillion KJ of heat contained in the 3m tonnes of slag produced at Angang’s main steelworks annually could also reduce costs by around RMB 100m ($15.8m), Su estimated. Angang reported a net loss of RMB 2.1bn in 2011.