Enhanced Recovery Process of Calcium Oxide and Metals from Steelmaking Slag with Net Carbon Sequestration

Corey Adam Myers, Takao Nakagaki, Takuya Mitamura

Research output: Contribution to journalConference articlepeer-review

2 Citations (Scopus)


The iron and steel making (ISM) industry is one of the largest CO2 emitters in the world. Despite a sustained global research effort, utilization of best available technologies will not result in CO2 reductions for the industry that are sufficient to meet the Paris Climate Agreement. One area of the ISM process that still contains a large untapped potential for CO2 reduction is the recycling of slag. Currently ∼46% of ISM slag in Japan is used as an additive in cement production, reducing CO2 emissions. However, substantial grinding of slag is necessary prior to usage, which reduces the net CO2 offset of this process. We propose an alteration to current cooling methods in order to reduce the grinding energy of slag. Additionally, this new method recovers more low entropy metallic species than current processes. Molten slag is poured into shallow trays and allowed to settle in order to increase the separation of accidentally entrained metals from the calcium silicate melt. Upon reaching the solidification temperature the slag is cooled rapidly enough to induce the amorphous structure necessary to use slag as a cement additive. After solidification, the slag is quenched from high temperature in an ambient temperature water bath to create fractures throughout the slag due to high thermal stresses. These fractures reduce the subsequent grinding energy and liberate disparate species. This method results in a potential reduction of CO2 emissions for the Japanese ISM industry of ∼12.4 Mt/year; an increase of 3.0 and 2.1 times that of water-based and air-based cooling methods that include heat recovery, respectively. The process is validated by simulation and experimental results.

Original languageEnglish
Pages (from-to)6246-6255
Number of pages10
JournalEnergy Procedia
Publication statusPublished - 2017
Event13th International Conference on Greenhouse Gas Control Technologies, GHGT 2016 - Lausanne, Switzerland
Duration: 2016 Nov 142016 Nov 18


  • Basic oxygen furnace
  • Blast furnace
  • CO reduction
  • Electric arc furnace
  • Ground granulated blast furnace slag
  • Recycling

ASJC Scopus subject areas

  • Energy(all)


Dive into the research topics of 'Enhanced Recovery Process of Calcium Oxide and Metals from Steelmaking Slag with Net Carbon Sequestration'. Together they form a unique fingerprint.

Cite this