Decarbonisation Technology - February 2025 Issue

Unlocking the potential of waste heat recovery Boosting efficiency and sustainability with waste heat recovery systems in the chemical industry

Sara Milanesi Exergy International

D ecarbonising chemical processes, much like other energy-intensive processes, is essential to achieve net zero by 2050 (IEA, 2023) . In fact, the chemical sector accounts for approximately 14.5% of all industrial CO₂ emissions (1,342 Mt from a total of 9,316 Mt) and ranks as the largest industrial energy consumer (IEA, 2022) . Global demand for chemical products is expected to grow by around 2.5 times by 2050, leading to a projected increase in both energy and non-energy uses of raw materials, heat, and electricity from 47.6 EJ to 88 EJ per year (Perego & Ricci, 2023) . This scenario presents a unique challenge with respect to decarbonisation of the chemical

industry as it is heavily reliant on fossil feedstocks (coal, crude oil, and natural gas) both as a source of energy and as raw materials. Various technologies and measures can be deployed to reduce energy intensity and mitigate carbon emissions in the sector. These include the production and use of green hydrogen, carbon capture utilisation and storage (CCUS) solutions, circular reuse of plastic waste, replacement of fossil fuel raw materials with biomass, and improvements in energy efficiency for process heat. Waste heat potential in the chemical industry Among energy efficiency measures, the recovery of waste heat represents a viable

Industry sectors

Chemical industry

11.7% 16.4%

Iron and steel

Non- ferrous metals Non-metallic minerals Paper and printing

0.3%

27.3%

9.9%

Reneries

34.4.7%

DE IT FR ES UK EL CZ PT RO AT FI BE SE PL NL

Available energy, TJ/yr Industrial sites

100

200

300

400

Figure 1 Map of industrial sites with significant waste heat recovery potential in Europe