With the development of China’s urbanization process, steel plants are gradually surrounded by cities. The coexistence of steel industries and cities has become inevitable. This paper presents a concept of upgrading and using municipal combustible waste (MCW) and in the ironmaking process as fuel. Blast furnace (BF) injection of MCW can reduce the environmental hazards of the MCW disordered treatment, and it can also reduce the consumption of fossil fuels in ironmaking. However, the low energy density, high content of harmful elements and difficulties in grindability and injection limit its application in BF injection. This research innovatively proposed a new technical route that uses hydrothermal carbonization technology (HTC) to treat MOW and applies the prepared hydrochar to BF injection. The research results showed that the energy density of hydrochar is significantly increased, the content of harmful elements is greatly reduced, and the grindability is significantly improved. Meanwhile, compared with the bituminous coal, the hydrochar has better combustion performance and can be used as an alternative fuel for BF injection. It can foresee that the steel plant may facilitate on building up a low carbon city by valorizing and using MCW in the ironmaking process for the substitution of fossil fuels.
Keywords Municipal combustible waste, Blast furnace injection, Hydrothermal carbonization, Hydrochar, Combustion