Energy Efficient Coil COating Process

Coil coating is an important industrial process used in a large part of industrial steel and metal alloy production and is associated with large equipment and large primary energy consumption. A large portion of the total plant size and energy requirements of coil coating plants is associated with the drying/curing process within a curing oven, a bottleneck in increasing production capacity. During this drying/curing process, organic solvents are evaporated from the applied liquid coating film and since they are flammable, the commonly used curing ovens with convection air drying technology must be operated well below the explosion limit (LOW) for safety reasons. ECCO offers a novel solution for curing oven operation that can not only dramatically increase the compactness and energy efficiency of the system, but also lead to increased production flexibility through a fuel flexible, modular and potentially energy self-sustaining process. The main idea is to heat the metal strip by IR radiation and operate the curing oven well beyond the upper explosive limit (UEL) to perform the drying and curing process in an atmosphere consisting mainly of solvent vapors used as fuel in IR radiation pore burners.

Figure 1: Comparison of conventional drying processes to ECCO concept.


This solution results in a 70% reduction in size/production capacity and a reduction in capital and operating costs of at least 40% each. Based on the previous activities at TRL 4, an interdisciplinary approach is envisaged, building on advanced materials, combustion technology and prediction tools for system design/optimisation, in order to bring this technology to TRL 6 with the active participation of the key industrial players and to realise a prototype kiln in an industrially relevant size and environment.


Video 1: Solvent during ignition in explosion test rig to determine the limiting oxygen concentration