In China’s coal reserves, low rank coal accounts for more than 55% of the total coal resources. In the past, the utilization of low rank coal was mainly combustion. At present, pyrolysis technology is used for cascade utilization of low rank coal, which can not only produce clean gas, but also has a low volatile matter content. It is the goal of iron and steel enterprises to seek the economy and high coal injection ratio, to improve the ratio of pulverized coal displacement and to obtain the maximum benefit.

The Inner Mongolia University of Science and Technology scholars use a self-made isothermal vertical tube furnace. By changing the mixing ratio (quartz sand / semi coke), temperature and oxygen volume fraction, the combustion test of the semi coke is carried out. The formation characteristics of NO in the combustion process of the semi coke in the blast furnace blowing process are analyzed and studied. The results showed that when the mixture ratio of quartz sand and semi coke was 55%, the interaction between particles and the two reduction reaction between NO and coke were the weakest. With the increase of combustion temperature, the combustion reaction of semi coke was accelerated and the generation time of NO (maximum about 80s) was shortened, and the process of NO reduction was promoted, and the production of NO was reduced; oxygen volume fraction was reduced. The prolongation of NO duration was not significantly affected by NO.