The connection between steel and chemistry
The Steel2Chemicals project is trying to bridge the gap between these two sectors and has investigated the possibility of giving carbon in steel gas a "second life. In short, it has investigated whether steel gas from the steel industry can be converted into a feedstock for the chemical industry.
Syngas as an alternative raw material
Our factories produce plastics and chemicals that we all use in our daily life. Think, for example, of applications in smartphones and mattresses. The building blocks for these plastics and chemicals are made in our so-called ‘blast furnaces’. To produce these building blocks, the fossil raw materials naphtha and LPG are converted in the blast furnaces under high temperatures into smaller building blocks; such as ethylene, propylene, butadiene and benzene.
We are always looking for alternative raw materials to make our products. Syngas, a mixture of carbon monoxide (CO) and hydrogen, is a good example. You can make it from natural gas, from biomass and from waste. It is a basic raw material from which we can make many of our products.
From Steel to Chemicals
The Steel2Chemicals project looked at the technical feasibility of syngas as a basic raw material for the production of plastics and chemicals. Syngas requires carbon monoxide (CO) and hydrogen. We have hydrogen in Terneuzen ourselves, but we do not have carbon monoxide. However, in the blast furnaces of steel producer ArcelorMittal (Ghent), large amounts of carbon monoxide (CO) and carbon dioxide (CO2) are formed during the production of steel. The (toxic) carbon monoxide is currently incinerated to prevent it from being released into the air. By capturing the carbon monoxide, it no longer needs to go into the air after combustion as CO2 but can be used in our production process as a carbon source. In this way, we become less dependent on fossil carbon resources and ArcelorMittal's greenhouse gas emissions can reduce. The carbon moves from "Steel" to "Chemicals" and is stored in materials instead of in the atmosphere.
A step back
The first phase of the cross-border project already started in 2016. Also called the ‘Carbon2Value project’. Together with ArcelorMittal in Ghent, research was conducted into the possibilities for capturing and revaluing CO2. With co-funding from ERDF (Interreg2Seas program -project 2S01-094), the foundations were laid for the removal of CO2 from blast furnace gas, and it was examined whether sulfur could also be captured from the gas.
After a successful first phase, the specially developed pilot plant could be reused as a supplier of the raw material (steel gas) in the subsequent Steel2Chemicals project. For this project, the consortium was expanded to include ArcelorMittal, TNO, Ghent University and Tata Steel, the Institute for Sustainable Process Technology and Dow Benelux. This diverse consortium is a good example of cross-border and cross-sector collaborations with different commercial interests, but with the common goal of reducing their impact on the climate.
The Steel2Chemicals project investigated the form in which the use of steel gas leads to the highest environmental gain at the lowest cost. One of the routes in this study was to make synthetic naphtha from blast furnace gas. This naphtha can be used in our crackers as a circular feedstock, where the carbon is eventually stored in materials. This process had already been developed in our laboratories in Terneuzen and was now tested at a larger scale in a pilot plant within the Steel2Chemicals project. The project was co-funded by the Top Sector Energy. The pilot plant provided important data in 2022 and 2023 to enable the joint study of the best routes. In addition, a significant quantity of synthetic naphtha was made for studies in the mini-cracker at UGent.
Results of the pilot project
The pilot project has now been completed. And the Steel2chemicals pilot plant has been moved from ArcelorMittal in Ghent to our site in Terneuzen. Recently, partner ISPT (Institute for Sustainable Process Technology) announced the results of the Steel2Chemicals project. You can read more information and its conclusions here. Some brief highlights below;
- The operation of the pilot plant shows that the main steps work as expected and also work in combination. The treated blast furnace gas was successfully converted into naphtha, which meets the properties needed to use it as a feedstock for chemical production. This confirmation on a larger scale aligned well with the prior laboratory tests.
- However, the pilot plant also revealed several technology development challenges. While the overall efficiencies of the plant are sufficient, they are lower than expected based on earlier benchmark experiments. The industrial blast furnace gas imposed several difficulties, especially when the input varies.
In summary, the project has taught us that using blast furnace gas as a feedstock is not an easy task for us. Technical feasibility depends on several factors, and it was not achieved to operate stably in the desired experimental range.
Although the cost of reducing CO2 emissions is lower than the cost of the Emissions Trading Scheme (ETS), the implementation cost is enormous in absolute terms. Large investments are involved, and the technology is clearly not ready yet for implementation. The risk to the steel industry remains significant and further improvement of the business case is necessary.
Terneuzen Path2Zero project
There are also other opportunities for us to make circular synthetic raw materials. That is why the Steel2Chemicals pilot plant has been moved to Terneuzen, so that we can reuse it to test with other gases as well. For example, with syngas from gasification of plastic waste or biomass.
This synthesis gas chemistry also plays an important role in the Terneuzen Path2Zero project. Here we will produce hydrogen from our own residual gases to reduce our CO2 emissions. In the first phase of this project, this circular hydrogen will be used as fuel. We can then capture the concentrated CO2 from hydrogen production for storage. You can read all the information about this here.
We are also developing a technology with Shell and TNO to electrify the blast furnaces. If this succeeds, we will no longer need hydrogen and can easily convert the internal residual gas into syngas without releasing CO2. From this circular syngas we can then produce our own feedstock, ultimately reducing the need for external (fossil) raw materials.
The future of syngas
Synthesis gas chemistry will thus play a central role in Dow's feedstock transition. The goal is to eventually obtain all of our raw materials from waste, biomass or residual streams. In this transition, the Steel2Chemicals pilot plant is of great importance for further development of the required technology. This is why this pilot has been moved to Terneuzen for the continuation of this, for Dow, very important experimental work.