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A novel configuration of the Ca-Cu looping process based on dynamically operated packed-bed reactors is proposed to convert blast furnace gas (BFG) into H2/N2 and highly concentrated CO2, accompanied by a large amount of high-temperature heat. Preliminary energy and mass balances of the process reveal that around 30% of the BFG can be upgraded via calcium assisted water gas shift (WGS) if only BFG is used as reducing gas in the reduction/calcination stage. A higher amount of H2/N2 can be produced by using other steel mill off gases, such as coke oven gas (COG) or basic oxygen furnace gas (BOFG), or natural gas in the regeneration of the CO2 sorbent. This decarbonized fuel gas could be used for onsite power generation or to obtain sponge iron by a Direct Reduced Iron (DRI) process, increasing the overall capacity of the steel plant. Energy efficiencies higher than 75% have been calculated, reaching maximum values around 88% in case of using natural as fuel gas for the sorbent regeneration stage. Low values for the specific energy consumption of around 1.5 MJLHV/kgCO2 and CO2 capture efficiencies higher than 95% support the further development of the proposed Ca-Cu looping process.

In the steel mills, in order to improve the circulation efficiency of iron ladles and steel ladles, save energy and promote the development of industrial automation, an iron ladles and steel ladles tracking management system based on radio frequency identification (RFID) and wireless local area network (WLAN) is proposed in this study. Meanwhile, to obtain the optimal number of online iron ladles, the theory of queuing is proposed for optimising the logistics of iron ladles. The system uses RFID and readers to obtain relevant location information. WLAN is used to realise communication between the crane terminals and the main control. Two queuing models are analysed and compared, then the optimal solution of online iron ladles is quantitatively calculated. Moreover, in order to intuitively reflect the on-site scheduling situation, a visualised operation interface is designed accordingly. The system has been used in a steel mill in Northeast China and achieved good performance.

In the present study, sludge from a steel wastewater treatment plant (SWWTP) was analyzed regarding its physicochemical characteristics and metal contents, and disposal options. For these purposes, grab sampling was used to collect 18 slurry and 18 cake sludge samples in 6 mouth (May-October 2012). Mann-Whitney U test, one sample T-test and Wilcoxon signed rank test were applied to analyze the obtained data. Canadian Soil Quality Guidelines (CSQG) and Florida Department of Environmental Protection Soil Cleanup Target Levels (FDEPSCTLs) were used to discuss the disposal fate of the generated sludge. The results showed that the order of the studied metals in the sludge was as: Fe>Al>Ca>Mg>Zn>Na>Pb>Mn>Cu>Cr>Ni>Co>Cd. It was found that due to higher concentration of Cu, Pb, Zn and Fe in the generated sludge, compared with CSQG and FDEPSCTLs, it is not suitable for residential and non-residential applications.