TRANSinter

Sintering process role in the (partial) transition to the Direct Reduction Route

To comply with the European Green deal (14/07/2021 – key target 2030: at least 55% cuts in greenhouse gas emissions – from 1990 levels), European steelmakers using the Blast Furnace (BF) route are considering a transition to direct reduction (DR) route, first fed by natural gas then by hydrogen when available in sufficient quantity. For this 2030 target, only a part of the existing BF's will be replaced by DR shafts. TRANSinter investigates solutions to support this first transition step based on the valorisation of the existing sinter plants (and of their existing efficient fumes de-dusting). Following solutions will be investigated:

• Adapted sinter for use in DR shafts: as an alternative to DR grade pellets in line with the future low availability of the required iron ores.
• Increased recycling rate: due to closure of sinter plants, by-products input in the remaining ones will need to increase but also new by-products (from the DR route) will have to be recycled. Impact on the process will be assessed and countermeasures investigated.
• Cleaner sintering process during the transition: conversion of low-quality residues from other sectors into bio-coals of reliable quality for being used as carbon sources; assessment of process actions to mitigate critical pollutant emissions; assessment of end-of-pipe treatments, not yet applied to sintering process fumes, for abatement of critical pollutant emissions linked to increased recycling rate; ‘Zero Emission Sintering’ original lay-out for minimizing the off-gas flow (10 to 20x lower) and the same for the CO2 and other pollutant emissions.

All those solutions will be investigated using the facilities available amongst the consortium, consisting in lab trials, modelling work and finally at pilot scale (sinter pot trials) followed by an exhaustive characterization (standards and more representatives) of the produced sinter for full understanding of the impact on BF and DR processes.

RE-CORD will perform the selection of urban and industrial waste streams and test their applicability as alternative carbon sources for the sintering process. Starting from the selected waste materials, RE-CORD will produce different biocoals by the integration of slow pyrolysis and chemical leaching, first in laboratory and then on a pilot scale. The biocoals will then be tested in the sintering process, aiming to substitute fossil carbon sources and mitigate the CO2 emissions of the steelmaking sector.