Paul Wurth, Dillinger & Saarstahl to Develop Dry Reforming Process
With H2Syngas, German steel makers Saarstahl and Dillinger will work with SMS Group’s Paul Wurth to further develop the technology of dry reforming of coke oven gas with blast furnace gas developed by Paul Wurth. A cooperation agreement to this effect was signed in 2020. The pilot plant is to be taken into operation in the summer at the site of the joint subsidiary of Dillinger and Saarstahl, ROGESA Roheisengesellschaft Saar GmbH in Dillingen. The dry reforming process allows the conversion of coke oven gas into a hot reducing gas or syngas that is injected in the blast furnace at tuyere or shaft level. The mixture of coke oven gas and blast furnace gas is compressed and heated-up in a regenerative heat exchanger of similar design than a traditional hot stove. At high temperature, the methane contained in the coke oven gas will react with the CO2 contained in the blast furnace gas to produce hydrogen and carbon monoxide. The injection of this hot reducing gas into the blast furnace entails a significant reduction in coke consumption. Such use of steelmaking gases for metallurgical purposes rather than for thermal purposes, translates into a significant reduction in CO2 emissions of up to 12%. The use of hydrogen can further improve and almost double the CO2 saving potential.
The first step in the development of the dry reforming technology is the construction of a pilot plant, which allows testing the dry reforming process at small scale with industrial gases. A further objective of the pilot plant is to test materials and components in regards to their suitability for the construction of an industrial scale plant. This is particularly important for the selection of refractory materials used in the regenerative heat exchanger. The start-up of the pilot plant is scheduled for summer 2021.
In the subsequent phases of the cooperation, it is planned to scaled-up the process to semi-industrial and later industrial scale with the support of public funding, by producing larger amounts of hot syngas and inject them at shaft level in one of the two blast furnaces in Dillingen. Elaboration of a blast furnace shaft injection technology is thus part of the dry reforming development.
The cooperation agreement provides Paul Wurth the opportunity to test the dry reforming process under industrial-like conditions, which will boost the development of the new technology. For Dillinger and Saarstahl, the future full-scale implementation of this technology will considerably decrease the carbon footprint and allow taking a next step forward towards green steel production.
H2Syngas is one of the leading projects of the cross-border hydrogen project in the Saar region, which is seeking IPCEI funding from the German government. The aim of the individual projects is to establish a green hydrogen economy in Saarland, France and Luxembourg. The various sub-projects are collectively initiating a sustainable transformation process in industry and in the mobility sector. The emission-free technologies that are emerging from this are driving structural change in the border region. As industrial customers, the Saarland steel companies Dillinger and Saarstahl are playing a key role here in the strategic development.
The first phase of the project will involve construction of a pilot plant to test the dry reforming process on a small scale. For the development and construction of this pilot plant the Luxembourg Ministry of Economy awarded Paul Wurth a grant under the applicable R&D aid scheme. The pilot plant is scheduled to be begin operating in the summer of 2021. In the next project phases, the process will be further developed to semi-industrial and later to industrial scale with support from public funding. The aim is for larger quantities of synthesis gas to be produced and injected into a blast furnace.