气基竖炉直接还原技术的发展现状与展望

 阐述了气基竖炉直接还原工艺的技术特点和发展现状，分析了在中国资源和能源条件下气基竖炉直接还原技术发展所面临的主要问题。基于气基竖炉直接还原工艺的特点，对该工艺的原料、还原气等进行了分析研究。指出非常规天然气资源的有效开采和加压煤制气工艺投资、运行成本的显著降低，将是未来气基竖炉直接还原技术发展的主要推动力，同时利用钢铁企业过剩的煤气资源和中国局部地区相对丰富的天然气资源生产直接还原铁，是今后中国气基竖炉直接还原技术发展的重要方向。参照唐山地区的原料和能源价格，对年产量为80万t/a的直接还原铁装置的生产成本和技术经济可行性进行了分析，分析结果表明：原燃料价格波动对DRI成本影响显著，其中还原气成本约占DRI生产成本的10%~25%；若按DRI替代转炉废钢计算效益，要求天然气价格低于1.8元/m3。

Current Status and Prospects of Gas-Based Shaft Furnace Direct Reduction Technology

The technical characteristics and current status of gas-based shaft furnace direct reduction process have been expounded and the major problems faced by gas-based direct reduction technology development under China’s resource and energy condition have been analyzed. Based on the characteristics of the gas-based shaft furnace direct reduction process, analysis of raw materials and reduction gases of this technology have been undertaken. It has been pointed out that a significant reduction in investment and operating costs of pressurized coal gasification technology and the effective exploitation of unconventional natural gas resource is the main driving force of the future development of gas-based shaft furnace direct reduction technology; meanwhile it is still another important direction of current gas-based shaft furnace development to produce DRI by taking advantage of the excess gas resources of steel plants and natural gas resource in some areas where the natural gas resource is relatively abundant. According to the raw material and energy prices in Tangshan region, the production costs of DRI has been calculated and the technical and economic feasibility has been analyzed under the scale of 0.8Mt/a. The results show that the effect of price fluctuations of raw materials on the DRI costs is significant, and the reducing gas accounts for about 10 %-25 % of DRI total costs. If considering the economic benefits of using DRI instead of scrap in converter, the natural gas price should be lower than 1.8yuan/m3.