Equans is renovating the boiler and fume treatment systems at the Virginal ERU in record time, while improving the efficiency and safety of the installations
An active contributor to the production of renewable energy, Energy Recovery Units (ERU) are large plants that produce heat and electricity from the combustion of our household waste. Located between Nivelles and Brussels (in Virginal), the InBW intermunicipal ERU is one of four energy recovery units in the Walloon Region. Built in the mid-1990s, it was in need of extensive renovation. As a partner of many ERUs (in Belgium, but also in neighbouring countries such as France and the Netherlands), Equans was responsible for replacing a large part of the boiler furnace (of production line 1), the fume treatment installations of lines 1 and 2, and also for replacing the extractors and conveyors for the ERU’s by-products (slag, ash and residues from the purification of fumes from the incineration of household waste). What’s at stake? Extending equipment life, improving performance and enabling Walloon Brabant to remain self-sufficient in household waste treatment.
The Virginal energy recovery unit is a Brabant factory that processes around 120,000 tons of waste per year and produces the electricity needed by around 10,000 households. While the authorities' objective is to encourage a reduction in the production of household waste, being able to effectively recover the residual materials that arrive every day at the Virginal plant's unloading dock remains a priority. Following the 20-year extension of its operating permit, the InBW intermunicipal company called on Equans teams to renovate a series of equipment on its 2 lines. This is a major challenge won after a public tender launched in 2021.
Teamwork under tight deadlines
“We completed the work on line 1 in December 2022,” explains Fabrice Belsot, Senior Project Manager at Equans. “This includes the renovation of the boiler furnace and the fume treatment equipment. We managed to complete the demolition, reassembly and testing of the installation in about 12 weeks. It's a mission we carried out under complicated conditions, particularly in terms of the delivery times for certain parts.”
"It must be said that the work on line 1 was carried out during the shutdown period, when production was at a standstill. In order to continue to provide the treatment of all household waste in Walloon Brabant, such a provision requires arrangements that are limited in time. This is why the Equans teams worked continuously 24/7, with peaks of 160 or even 180 employees on site,” says Martin Comblin, Project Manager at Equans.
Providing a comprehensive service with a single point of contact for all Equans teams was appreciated within the InBW. “This contract is an EPC (Engineering, Procurement, Construction & Commissioning) type contract,” adds Fabrice Belsot. “It covers the entire value chain. It starts with studies and design, then the purchase of equipment. This is followed by installation and commissioning. We coordinated and organised the planning of all the techniques. This includes pressure installations, assembly of large electromechanical equipment, electrical and instrumentation work, command and control, refractory work, and the laying of ducts and piping.”
More environmentally friendly
With the 30-day industrial sprint now completed, the new facilities have already proved their worth. “Techniques have evolved a lot since the 1990s, particularly in terms of fume treatment. Dust, heavy metals, dioxin, nitrogen oxides, acid pollutants, etc. Discharge standards are becoming increasingly strict, and the new installations will make it possible to comply with them, with the addition of lesser quantities of chemical reagent injections. It is therefore more ecological and economical!”, explains Aurélie de Potter, Construction Manager.
The new equipment installed at Virginal's ERU has many advantages: higher yields, better performance, lower operating costs. In terms of safety, it is also more advanced. Before the renovation, the furnace was operated manually. It is now fully automated, which increases the production of steam - and therefore electricity - and the stability of the system. Work on line 2 is expected to start in March 2023.