中文摘要：

针对国内某大型钢铁厂高炉加湿富氧增加高炉煤气中H2含量，从而减少CO2排放的生产，在实验室条件下采用程序还原炉研究了不同H2含量和不同还原气（CO＋H2）比例对烧结矿低温还原粉化行为的影响，并采用SEM电镜对还原过程中烧结矿的微观结构进行了观察，定义了烧结矿的裂纹密度以表征烧结矿的结构变化。研究结果表明，在500℃下，随着H2含量由0增加到12％，烧结矿还原度呈现下降的趋势，烧结矿还原粉化指数RDI＋3.15有所升高，从58％增加到62．5％，烧结矿的裂纹密度急剧减小，由105m／m^2减少到23m／m^2；随着还原气比例（CO＋H2）由20％增加到40％，烧结矿的还原度急剧增加，烧结矿的R＋3.15由58．5％减少到54％，烧结矿的裂纹密度急剧增加，从102m／m^2增加到170m／m^2。

英文摘要：

In view of humidifying and oxygen enriched BF condition in a large sized domestic iron and steel plant,increas- ing the H2 content of BF gas will reduce CO2 emissions. Under the laboratory condition, the program reduction furnace was adopt- ed to study the influences of H2 and （ CO ＋ H2 ） contents on the reduction and disintegration behavior of sinter. The Scanning e- lectron microscope（SEM） was used to observe sinter microstructure during reduction process, and the sinter crack density was defined to characterize the structure change of sinter. The research results show that, at 500 ℃, with the increase of H2 content from 0 to 12%, the sinter reduction index shows a trend of decreasing, and the RDI＋3.15 increases somewhat from 58% to 62. 5% ,the crack density of sinter decreases sharply from 105 m/m^2 to 23 m/m^2. With the increase of reducing gas ratio （ CO ＋ H2 ） from 20% to 40%, the reduction index of sinter increases dramatically, and the RDI ＋ 3.15 reduces from 58. 5 % to 54%, the crack density of sinter increases dramatically from 102 to 170 m/m^2.