Process flow sheet evaluation of a nuclear hydrogen steelmaking plant applying high temperature gas-cooled reactors for efficient steel production with less CO emissions

Kasahara, Seiji  ; Inagaki, Yoshiyuki; Ogawa, Masuro

Nuclear hydrogen steelmaking (NHS) system was evaluated by flow sheet analysis using High Temperature Gas-cooled Reactors (HTGRs) and thermochemical hydrogen production IS process. Heat input and CO emissions of the system including material production, material transportation, and power generation were evaluation criteria. The result was compared with that of a conventional blast furnace steelmaking (BFS) system. Though total heat input to the NHS system was 141-159% of the BFS system, CO emissions were 9-17%. Pre-heating of hydrogen by coal combustion before blowing to the shaft furnace was effective to decrease heat input although CO emissions increased a little. Direct nuclear pre-heating was expected to be less heat input without increase of CO emissions if the problems with nearby location of the nuclear reactor to the steelmaking plant would be solved. Influence of hydrogen production thermal efficiency on heat input of the NHS was great. A conceptual design of a plant unit of the NHS system producing steel of 7.4310 t/y with a HTGR of 600 MW heat and a shaft furnace and an electric arc furnace was proposed.