S&T: Producing greener steel with CISDI’s dry desulphurisation tech

CISDI has independently developed dry desulphurisation tech and equipment for blast furnace gas.

This tech places the BFG de-S system upstream of the top gas recovery turbine or the blast furnace’s power recovery turbine, which is a high pressure side, to achieve centralised desulphurisation and treatment.

It is an innovative, effective means of conducting source control and reducing resistance loss, temperature drop and space. It also improves gas excess energy recovery while increasing heat values.

It is a different approach to that of conventional wet de-S systems, which mainly operate from a low pressure side, downstream of the TRT/BPRT. The older method impedes the reutilisation of BFG’s excess energy and its heat values to a high standard.

An environmental protection material lab, built at CISDI in 2019, has been devoted to researching and developing blast furnace gas sulphur control tech and high-performance desulphurising catalysts, which are seen as essential for the development of greener ironmaking processes demanded by the sector.

In 2020, the lab team carried out pilot tests at China’s Tranvic Steel Plant in Sichuan Province and Baosteel Zhanjiang in Guangdong Province. They screened and evaluated the adaptability of various de-S catalysts operating in the same BFG working conditions.

The team applied its results to an industrial testing platform to verify their effectiveness from process, equipment and catalysing performance perspectives. They were proven to have met the ultra-low emissions standard controlling BFG’s sulphur content to within 30mg/m³ and to a minimum level of below 15mg/m³.

Pilot testing is continuing at Tranvic Steel and Baosteel Zhanjiang in a bid to develop higher performance of catalysts and further reduction of the desulphurisation system’s operation costs.

CISDI’s dry desulphurisation system provides a new solution for steel enterprises wanting greener developments and is a solid step forward in response to China’s ULE requests to the steel sector.

The BFG desulphurisation lab team working at a pilot test site