Journal of Materials Research and Technology Journal of Materials Research and Technology
J Mater Res Technol 2017;6:258-70 DOI: 10.1016/j.jmrt.2017.05.007
Original Article
A theoretical study using the multiphase numerical simulation technique for effective use of H2 as blast furnaces fuel
Jose Adilson de Castroa,, , Cyro Takanob, Jun-ichiro Yagic
a Graduate Program on Metallurgical Engineering, Federal Fluminense University, Volta Redonda, RJ, Brazil
b Metallurgical and Materials Engineering Department, Polytechnic School, University of São Paulo, São Paulo, SP, Brazil
c Tohoku University, Sendai, Japan
Received 01 March 2017, Accepted 16 May 2017
Abstract

We present a numerical simulation procedure for analyzing hydrogen, oxygen and carbon dioxide gases injections mixed with pulverized coals within the tuyeres of blast furnaces. Effective use of H2 rich gas is highly attractive into the steelmaking blast furnace, considering the possibility of increasing the productivity and decreasing the specific emissions of carbon dioxide becoming the process less intensive in carbon utilization. However, the mixed gas and coal injection is a complex technology since significant changes on the inner temperature and gas flow patterns are expected, beyond to their effects on the chemical reactions and heat exchanges. Focusing on the evaluation of inner furnace status under such complex operation a comprehensive mathematical model has been developed using the multi interaction multiple phase theory. The BF, considered as a multiphase reactor, treats the lump solids (sinter, small coke, pellets, granular coke and iron ores), gas, liquids metal and slag and pulverized coal phases. The governing conservation equations are formulated for momentum, mass, chemical species and energy and simultaneously discretized using the numerical method of finite volumes. We verified the model with a reference operational condition using pulverized coal of 215kg per ton of hot metal (kgthm−1). Thus, combined injections of varying concentrations of gaseous fuels with H2, O2 and CO2 are simulated with 220kgthm−1 and 250kgthm−1 coals injection. Theoretical analysis showed that stable operations conditions could be achieved with productivity increase of 60%. Finally, we demonstrated that the net carbon utilization per ton of hot metal decreased 12%.

Keywords
Blast furnace, Mathematical model, Mix injection, CO2 emission
J Mater Res Technol 2017;6:258-70 DOI: 10.1016/j.jmrt.2017.05.007