Overview of waste heat in the industry in France

Panel: 4. Undertaking high impact actions: The role of technology and systems optimisation

This is a peer-reviewed paper.

Authors:
Marc Berthou, EDF R&D, Département TREE, France
Daniela Bory, EDF R&D
Département PI, France

Abstract

The aim of this paper is to evaluate the amount of waste heat in the manufacturing industry in France.

It is proposed to characterize the waste heat with a "top down" method using a statistical approach. This method is based on the combination of an energy consumption database with a thermal equipments stock characterization database. This method is completed by an expertise of industrial sectors and processes.

The French industry consumes 417 TWh (2009) which represents 25% of its total energy consumption, of which 70 % (300 TWh) is covered in this study. Included warm effluents are:

- combustion gases from: boilers and furnaces

- steam from: dryers

- cooling fluids from: air compressors, refrigeration compressors, refrigeration condensers, heat exchangers in desuperheaters of the refrigeration groups, clean-in-place (CIP effluents)

The waste heat is characterized by its energy value. This energy value is given by the type of warm effluent, by the temperature level, by the availability of heat and by the industrial sector. Energy data are analyzed on the basis of these parameters.

Waste heat in the industry is estimated at 100 TWh for a temperature range between 40 and 250°C. The food industry, the paper industry, the chemicals and the non-metallic materials industries are the sectors with the largest potential. In the food industry, the waste heat mainly results (75 %) from the cooling fluids in the condensers of refrigeration groups at a temperature around 40 °C and from the vapor of dryers at a temperature over 100 °C. The temperature levels of the waste heat are very different from one industrial sector to another.

This analysis provides data to assess how much waste energy is recoverable. This energy can be recovered directly or through the use of heat pump and storage device for the internal needs of the factory. This energy can also be used for external uses of the industry by injecting it into a district heating or for electricity production.