生物质煤焦-烟气偏析循环烧结污染物协同控制基础研究

The sintering flue gas pollutant is the main source for air pollutant in iron and steel industry, co-governance of multi-pollutant in sintering flue gas has become the inevitable choice in iron and steel industry. Facing the strict and diversified emission standard of flue gas pollutant, the project aims at governing air pollutant comprehensively in iron and steel industry and proposes “sintering process of biomass coal fuel and segregation circulating flue gas” to control pollutants of sintering flue gas synergistically. The project research on the preparation and application of biomass coal fuel, and the application of segregation circulating sintering flue gas. Utilizing the biomass coke with low S and N to realize source control of sintering flue gas pollutant. The sintering flue gas of high temperature and high pollutant is selected for circulation sintering. By riching oxygen to satisfy the condition of sintering atmosphere and increase the circulating amount of sintering flue gas to realize the enrichment and removal of sintering flue gas pollutant. By riching blast-furnace gas to make up for the heat shortage of biomass coal fuel, and to increase the temperature and distribution uniformity of the material layer to improve sinter properties. By establishing sintering process of biomass coal fuel and segregation circulating flue gas for co-control the fuel gas pollutant, which can realize the economical cleaner production and sustainable development in iron and steel industry.

烧结烟气污染物是钢铁工业大气污染的主要来源，面对日益严格的多元化烟气污染物排放标准，烧结烟气多污染物协同控制已成为钢铁工业污染物治理的必然选择。本项目以钢铁工业大气污染物综合治理为目标，提出“生物质煤焦燃料烟气偏析循环烧结工艺”协同控制烧结烟气污染物。重点开展生物质煤焦烧结燃料的制备与应用基础研究和富氧富煤气烟气偏析循环烧结应用基础研究。通过利用低S、N的生物质煤焦烧结生产，实现烧结烟气污染物的源头控制；选取高温高污染物烟气进行循环烧结，通过对烟气富氧满足烧结气氛条件提高烧结烟气循环量，实现烧结烟气污染物循环富集和脱除；通过富煤气弥补生物质煤焦燃料烧结热量不足，提高料层温度及分布均匀度，强化烧结成矿性能。建立生物质煤焦烟气偏析循环烧结污染物源头和过程协同治理技术体系，实现钢铁企业经济化清洁生产和可持续发展。

我国钢铁制造以“高炉-转炉”传统长流程为主，其中铁矿粉烧结工序大气污染物种类杂、数量多、烟气温度波动大，多污染物协同治理最为迫切。项目以钢铁执照流程大气污染物重点排放工序（铁矿粉烧结造块工序）为切入点，基于烧结烟气污染物“源头削减-过程控制”理念，提出“生物质燃料-烟气循环烧结”技术匹配传统末端治理工艺路线，形成了烧结烟气污染物全过程控制技术，大幅降低烧结烟气中SO2、NOx等主要污染物排放浓度，实现钢铁企业的减量化、经济化清洁生产和可持续发展。项目完成了生物质混煤热解机理及反应动力学研究、铁矿粉烧结燃料生物质煤焦制备研究、生物质煤焦性能优化改性研究、铁矿粉低温烧结配矿结构优化研究、铁矿粉烧结烟气污染物形成机理研究以及基于生物质燃料铁矿粉偏析循环烟气烧结研究。获得了生物质烧结燃料制备工艺参数，解析了烧结混合料在烧结各个料层中烟气污染物SO2和NOx的排放特性，构建了烧结料层温度分布与烧结矿性能评价体系，分析了烧结混合料的碱度、MgO含量和Al2O3含量对烧结矿液相生成温度和液相生成量的影响规律，确定了低温烧结成矿配矿结构，系统阐释了基于生物质燃料烟气循环烧结工艺对烧结指标及成矿性能和烟气污染物生成与排放特性的影响规律，并优化了烟气偏析循环烧结方案，为铁矿粉烧结多污染物协同控制提供理论基础。.项目累计发表文章10篇，其中SCI索引3篇；申报专利2项，授权专利1项；项目成果获2019年河北省科技进步二等奖1项，2020年河北冶金科学技术二等奖1项；培养博士2名，硕士3名；参加学术会议6次，完成了任务书规定的研究任务。