RESUMO
The production of iron and steel is energy-intensive that motivated the emergence of various energy-saving technologies to reduce energy consumption. However, the effects of water-saving brought by these energy-saving technologies are rarely examined which can lead to misevaluation of their economic feasibility. In this regard, material flow analysis (MFA) was used in this study to establish the water-energy nexus and examine the potential of water-saving and energy-saving effects in the condition of applying various mixes of the 16 technologies (Ministry of Industry and Information Technology, 2015-2016) in iron and steel industry. Meanwhile, this study classified the selected 16 energy-saving technologies into three groups: direct water-saving technology, indirect water-saving technology, and water consumption technology. The low-temperature steel rolling technology is the only water-consuming energy-saving technology in this study; its indirect specific water computation reaches 0.06â¯m3/t. The remaining 15 energy-saving technologies have the potential of saving water indirectly, with averaged indirect specific water-saving amounting to 0.28â¯m3/t. This study also built an evaluation scheme of cost-benefit analysis for energy-saving technologies. With consideration of benefits brought by water saving, eleven technologies have the potential to achieve economic feasibility compared to nine in which mere energy-saving effects being considered. The results show that if the studied 16 technologies are implemented simultaneously, the comprehensive specific energy consumption will be reduced by 4.28â¯MJ, and the specific fresh water consumption will be reduced by 0.68â¯m3. Meanwhile, this research found that the cost of most energy-saving technologies will be decreased by an average of 5.52 CNY/GJ, despite the cost of low-temperature steel rolling technology increased by 0.68 CNY/GJ. This study evaluated the cost-effectiveness of energy-saving technologies taking the benefits of water conservation into consideration. It could provide references for decision-makers to develop commercialization strategies on energy saving technologies in the steel industry.