Swiss cement manufacturer Holcim has appointed the joint venture between BESIX and DENYS as main contractor for the civil works of its new state-of-the-art plant in Obourg (Mons, Belgium). The GO4ZERO project aims to produce close to 2.3 million tonnes of carbon-neutral cementitious materials per year by 2029. BESIX and DENYS are building the civil works whilst, in a separate contract, BESIX’s subsidiary Franki Foundations is handling deep foundations.
Drastic carbon reduction
The production facility will feature an innovative air-oxyfuel switchable kiln with carbon purification technology. The project will be carried out in two phases. The first consists in replacing the current wet process clinker kiln with a next-generation innovative air-oxyfuel switchable dry process kiln, with unprecedented circularity, innovation and low environmental footprint performances. While being operated in standard air combustion, this will enable a reduction in CO2 emissions of nearly 30% per tonne of clinker. The second phase consists of switching to oxycombustion and implementing additional equipment to allow the residual process and combustion CO2 to be purified above 99.5 %. Captured CO2 will then be transported via pipeline to portside liquefaction and storage facilities in Antwerp before being loaded onto specialised ships and transported at very low temperatures to North Sea sequestration wells.
The GO4ZERO project transforms cement manufacturing at every stage of the process. Accelerating decarbonized energy use, more than 95 % of its energy will be sourced from alternative fuels with an ambition to become 0 fossil fuel, while over 30 % of its raw mix will come from partly decarbonized alternative raw materials – predominantly non-recyclable waste generated by other industries, thereby advancing circularity. Moreover, some ongoing developments will allow to generate locally more than 150 GWh of decarbonized electricity thanks to large-scale floating solar panels on former chalk quarries and waste heat recovery systems.
A strong partnership
The fully integrated joint venture BESIX-DENYS has been trusted with civil works on the project, which have started recently. The scope of works is particularly challenging as it encompasses more than 70 different structures which need to be delivered to the client in less than 15 months. The structures include for example:
- a 60-metre-high cone-shaped silo with sliding formwork and an integrated inverted concrete cone;
- electrical substations;
- a 25-metre-high concrete shell structure supporting a steel structure pre-heating tower of 145-metre-high in total;
- a covered corrective storage area of more than 200-metre-long;
- and a train unloading station (as the plant will use train-delivered limestone from deposits in Antoing-Tournai).
BESIX Group subsidiary Franki Foundations is responsible for the deep foundations of the facility. This work encompasses the installation of close to 1,500 Omega screw piles up to 32 metres deep, anchored in dense chalk. The foundations were redesigned in-house by Franki Foundations, which led to a reduction in concrete of almost 50% compared with the initial request. The deep foundation works started in August this year, and should be concluded in February 2025.
Mark Beyst, General Manager of BESIX Belgium-Luxembourg: “We are thrilled to contribute, together with our partner DENYS, to Holcim’s ambition to achieve carbon neutrality through this state-of-the-art and highly technological production facility. GO4ZERO is perfectly aligned with BESIX’s commitment to reduce its carbon footprint and assist clients in lowering theirs through innovative solutions.”
Geert Dhont, COO Benelux of DENYS: “We are honoured and look forward to a successful collaboration, together with our partner BESIX, in this ambitious and ground-breaking project. Playing a part in Holcim’s GO4ZERO program by contributing to this carbon neutral cement production facility follows our company’s vision to “build to improve the quality of life and people through innovation & technology”. We‘re excited about the new technologies, construction methods and materials we’ll be embracing throughout this project.”
About BESIX
BESIX is a leading Belgian group, based in Brussels and operating in 25 countries and on 5 continents, in the construction, real estate development and concessions sectors. Active since 1909, its iconic achievements include Dubai's Burj Khalifa, the tallest tower in the world, buildings of the European Parliament in Brussels as well as the Grand Egyptian Museum, on the Giza pyramids plateau.
The Group's engineering department enables BESIX to carry out complex and unique projects, particularly in terms of technical and environmental aspects.
About DENYS
DENYS is an independent construction group headquartered in Belgium, active since 1923 and employing 1,800 people worldwide. Recognized for its focus on innovation and its multidisciplinary expertise, it specializes in water, energy, mobility, infrastructure, civil engineering, tunnelling, restoration, and special building techniques. With this unique breadth of skills and experience, Denys is a trusted partner for complex construction and infrastructure projects across Europe and Africa.