A 75-tonne green, highly-efficient electric arc furnace and a ladle furnace have been successfully hot tested at Dugang in China’s Sichuan Province.

It features CISDI-AutoARC, which was awarded second place in China’s 2019 national S&T advances.

All systems are running stably, taking Dugang’s demo Mini-mill plant into pilot production.

The Mini-mill, with EAF scrap melting at its core, consumes a third of the energy required at an integrated plant reliant on a blast furnace plus basic oxygen furnace, and produces only a third of the emissions.

EAF-based Mini-mills and the development of greener EAF products have now become a leading trend in the steel sector.

In response to longstanding problems in EAF production – namely the low utilisation ratio of electric energy, oxygen and carbon powder, the high consumption of electrodes and slagging materials, and dioxin pollution - CISDI and its partners have made major breakthroughs in critical process, equipment and control.

CISDI-AutoARC’s application at Dugang features:

-  CISDI-DMI-AC digital electrode regulation system for the EAF and the LF

-  CISDI-SCDF stepwise continuous feeding, enabling scrap’s travel speed to reach 7.8 metres per minute

-  High-temperature fume’s excess heat recovery for power generation, which is under construction.

These green, high-efficiency and low-consumption core technologies have helped Dugang achieve higher quality production, a wider variety of products and substantial cost savings.

CISDI’s teamwork ensured all equipment installation and commissioning tasks were carried out on time, despite issues caused by the pandemic.

Dugang’s Mini-mill plays a vital role in the transformation of its holding company, Sichuan Metallurgical Group, to green, smart and super-efficient levels.

The CISDI-AutoARC in operation at Dugang

Dugang’s green, efficient electric arc furnace carries out tapping

A liquid steel ladle tapped from the CISDI-AutoARC is ready for transportation to the LF for refining

The CISDI-AutoARC with scrap charging at Dugang