Drastic’s Spanish Demonstrator is led by the Celsa Group, with support from Lezama Demoliciones, Polytechnic University of Catalonia (UPC), and Sorigué. It is located in Sorigué’s facilities in Balaguer, Lleida. The project partners for this Demonstrator are dispersed across the Spanish peninsula, mainly in Catalonia and the Basque Country. 

Advancing sustainable cement and steel practices in building construction 

Attending to the structural layer of buildings, the Spanish Demonstrator tackles two materials which can have a relatively large environmental impact within the total life cycle of buildings; cement and steel. 

With no established ecosystem for disassembling and reusing structural steel elements, this Demonstrator looks to implement and prove the feasibility of such a system.

Additionally, the Spanish Demonstrator aims to repurpose white slag (a by-product from the secondary steelmaking process) via its application as a supplementary material to produce concrete. The white slag will be pre-processed by Adec Global, a pioneering company dedicated to managing and utilising steel slag into recycled aggregates via its application as a supplementary material within concrete and cement.

Celsa Group, as a steel provider, will perform quality tests on the harvested steel structural elements, alongside Universitat Politècnica de Catalunya, a specialist in engineering, architecture and science. The Celsa Group will also provide the white slag for this project.

As a material, white slag can be inherently expansive. This can cause challenges when used in building and construction applications. As part of their work on the project, UPC will determine the optimum percentage of clinker cement substitution to balance this expansive quality, when integrating white slag into the cement mix, to ensure the desired properties and behaviour of the final product are achieved.   

The construction of a circular warehouse to aid decarbonisation

The Spanish Demonstrator will consist of a warehouse construction, in which structural elements from the dismantled Litoral Thermal Power Plant in Almería will be reused. This plant will be deconstructed by Lezama Demoliciones, a company that specialises in selective demolition and sustainable dismantling in the south of Spain. 

The Celsa Group aims to address the carbon emissions generated by their use of electricity, in order to become a carbon neutral company by 2050. As part of this objective, the Celsa Group is seeking other ways to decarbonise the Spanish Demonstrator project’s processes. 

By incorporating white slag into the cement mix, the Spanish Demonstrator will utilise a product that was previously considered waste. This will reduce the percentage of raw material that needs to be harvested, hopefully contributing to further decarbonisation within the sector.

Challenges faced by the Spanish demonstrator

One of the main challenges the Spanish Demonstrator faces is providing quality assurance for the final product. 

The integrity of the reused structural elements must be ensured. However, some estimates will be necessary to determine their suitability due to the lack of standardisation in reuse materials. Although guidelines exist, interpretations vary. This project will conduct an extensive study with more tests than usual to see and understand the correlations between multiple tests and trials.