Sequence Impulse Process for Blast Furnace OPEX Reduction

The Sequence Impulse Process (SIP) is a technology that injects high-pressure oxygen in the blast furnace to penetrate into the raceway of the blast furnace. The technology helps blast furnace operators to reduce the OPEX whilst also supporting a transition to a lower carbon operation.

The Sequence Impulse Process (SIP) delivers a unique combination of benefits. By investing in this technology, operators can benefit today from significant reductions in blast furnace OPEX. The process supports improving furnace conditions to allow exchange of costly coke for higher injection rates of cheaper coal. Improved raceway conditions lead to improved gas distribution and utilization, as well as enhanced liquid drainage capabilities. A better raceway provides a stable, productive furnace. Better gas efficiency also results in lower fuel consumption meaning lower CO₂ emissions. Additionally, through higher oxygen penetration, heat loads are generated more towards the central zone of the furnace, improving tuyere life and reducing heat losses to the tuyeres and furnace walls.

Coal injection into the blast furnace results in char materials accumulating, which restricts the penetration of the "dead-man" of coke. This limits the flow distribution into the center of the furnace and reduces gas utilization. By pulsing high-pressure oxygen in a pre-determined sequence to each tuyere, shock waves penetrate deep into the raceway of the blast furnace, combusting the fine char and improving coke permeability. This enhances gas utilization and the potential for better furnace drainage.

Benefits of Implementing the Sequence Impulse Process in the Blast Furnace

• Reduced total fuel rate results in a reduction of blast furnace OPEX
• Improved gas distribution and drainage enhance production potential
• Increased gas utilization enables the exchange of coke at higher rates of injected coal
• Better furnace stability, even with the use of lower-quality raw materials
• The net result is a reduction in total CO₂ emissions
• Reduced CO₂ emissions result in lower emission tax costs, where applicable
• Offers a rapid Return on Investment (ROI), typically 12–18 months

"As a supporter and campaigner for the new technology in-house, I am, of course, very happy that it works reliably and safely. However, I wouldn't have thought that even such 'small' amounts of SIP oxygen would have such a strong effect in the blast furnace. In this respect, my expectations have been exceeded."

Dr. Rainer Klock

Managing Director at thyssenkrupp AT.PRO tec GmbH

"The task of every blast furnace operator is to produce pig iron at low costs with a high throughput. With the more stable furnace behavior and the cost savings on reducing agents, the SIP plant makes a significant contribution to this."

Dr. Dirk Gotthelf

Head of Hot Metal, Plant Schwelgern, thyssenkrupp Steel Europe