Making the most of waste heat: ALLICE has published a new explanatory infographic!
The industrial sector accounts for approximately 20 per cent of France’s energy consumption. The majority of this energy – 402 TWh according to INSEE in 2021 – is used or converted into heat, with massive losses occurring during its use. Against a backdrop of rising energy prices, waste heat is therefore proving to be a real driver of competitiveness, and a key concern for manufacturers.
In line with its mission to share and disseminate knowledge that benefits the entire sector, ALLICE has published an infographic designed to provide a better understanding of the opportunities for heat recovery in industrial processes, with a view to reducing energy consumption.
Based on the study ‘Waste Heat: Potential for Project Roll-out’, this is an educational resource aimed at manufacturers, setting out the approach to be adopted before embarking on a waste heat recovery and utilisation programme.
A diagram to answer questions from manufacturers
What are the options for recovering waste heat from an industrial process? Which type of recovery should be prioritised?
How can projects to recover energy from waste heat be successfully implemented?
This ALLICE illustration aims to answer these questions by proposing a typical order of priority for methods of reducing and utilising heat generated by an industrial process. These priorities may vary on a case-by-case basis depending on the constraints of individual sites and industrial processes (technical, economic, regulatory, etc.).
The diagram sets out a standard order of priority (from 1 to 10), as defined on the right-hand side of the diagram.
Understanding the role of waste heat in energy efficiency: Identifying the right priorities using the ALLICE infographic
- The first step is to prevent the release of unnecessary heat through process changes [priority 1] or the implementation of best practice [priority 2].
Examples of process changes: selection of Best Available Techniques (Best Reference)[1], selection of the most appropriate energy source.
Examples of good practice: reducing equipment losses (thermal insulation), optimising equipment control systems, optimising plant rooms, and limiting temperature and pressure levels.
- Secondly, heat that is unavoidable but not necessary can be utilised through energy integration for on-site consumption within the process [priorities 3 and 4].
- Once the unnecessary energy has been optimised, the minimum energy required remains. Part of this energy is stored within the product. The remainder can be recovered through energy integration within its environment (internally within the factory for use in other processes, externally to supply other sites with heat requirements, or through a change of energy carrier) [priorities 5 to 10].
- Residual waste heat that is neither recovered nor stored in the product is lost for good.