Converter Carbon Steelmaking with the LD Converter

The demands for product quality, plant productivity, and availability are increasing steadily. LD (BOF) plants by Primetals Technologies are at the forefront of the steelmaking industry, renowned for their reliability and economic efficiency. In the early 1950s, engineers searching for alternatives to the Siemens-Martin furnace could not have foreseen the revolutionary impact of their development of the Linz-Donawitz (LD) converter, also known as the Basic Oxygen Furnace (BOF). Today, this technology underpins approximately 70% of global steel production. Primetals Technologies has planned, built, and commissioned over 200 LD (BOF) converter plants, including numerous turnkey projects.

In 1952, the Linz-Donawitz (LD) process, also known as the BOF process, was developed in Austria and quickly became the standard for iron ore-based steelmaking. Since its inception, the process has undergone continuous optimization and improvement in terms of consumption figures, productivity, and maintenance, and is now successfully utilized in steel plants worldwide.

A significant portion of the advancements and refinements in the LD converter process have been made by Primetals Technologies and its predecessor companies. Today, Primetals Technologies stands as a leading solution provider for converter steelmaking, boasting extensive experience and a broad reference base for entirely new plants, as well as highly specialized and customized revamping and modernization projects.

Despite the maturity of the LD converter steelmaking process, Primetals Technologies is consistently investing in advancements to enhance the process and equipment further. Modern numerical simulation methods, process models, logistic simulations, and complete 3D modeling are among the powerful tools employed for this purpose. Recent development trends include more precise process control and optimization through numerical models, increased automation to minimize manual labor in hazardous areas, equipment optimization to extend lifespan, and measures to reduce CO₂ emissions, such as increasing scrap rates or integrating with the Smelter. These incremental steps, coupled with extensive experience, enable Primetals Technologies to maintain a competitive edge and offer innovative solutions to its customers.

Special Converters

While the LD converter process is employed for normal carbon steel production in nearly all integrated steel plants globally, special converters are utilized for high-alloyed steels, processing high rates of scrap and Direct Reduced Iron (DRI), or handling hot metal with very high silicon content. Primetals Technologies offers a diverse portfolio of special converters, with the most notable being combined blowing converters that utilize bottom tuyeres in conjunction with a top blowing lance. These converters are characterized by bottom blowing with natural gas-cooled tuyeres in the converter bottom and equipment for lime and coal injection. Bottom blowing ensures excellent mixing of the liquid bath, bringing all metallurgical reactions close to equilibrium. As a result, the yield of the process is higher compared to pure top blowing converters, and process control is more straightforward.