Division BAT 8 In order to reduce energy consumption and the overall environmental impact from drying/curing processes, BAT is to use one or a combination of the techniques given below.
United Kingdom
| The selection of the drying/curing techniques may be restricted by the substrate type and shape, product quality requirements and the need to ensure that the materials used, coating application techniques, drying/curing techniques and off-gas treatment systems are mutually compatible. | |||
| Technique | Description | Applicability | |
|---|---|---|---|
| (a) | Inert gas convection drying/curing | The inert gas (nitrogen) is heated in the oven, enabling solvent loading above the LEL. Solvent loads of > 1 200 g/m3 nitrogen are possible. | Not applicable where dryers need to be opened regularlyf1. |
| (b) | Induction drying/curing | Online thermal curing or drying by electromagnetic inductors that generate heat inside the metallic work-piece by an oscillating magnetic field. | Only applicable to metal substrates. |
| (c) | Microwave and high-frequency drying | Drying using microwave or high-frequency radiation. | Only applicable to water-based coatings and inks and non-metallic substrates. |
| (d) | Radiation curing | Radiation curing is applied based on resins and reactive diluents (monomers) which react on exposure to radiation (infrared (IR), ultraviolet (UV)), or high-energy electron beams (EB). | Only applicable to specific coatings and inks. |
| (e) | Combined convection/IR radiation drying | Drying of a wet surface with a combination of circulating hot air (convection) and an infrared radiator. | Generally applicable. |
| (f) | Convection drying/curing combined with heat recovery | Heat from off-gases is recovered (see BAT 19 (e)) and used to preheat the input air of the convection dryer/curing oven. | Generally applicable. |
Annotations
Footnotes
- f1
-
The selection of the drying/curing techniques may be restricted by the substrate type and shape, product quality requirements and the need to ensure that the materials used, coating application techniques, drying/curing techniques and off-gas treatment systems are mutually compatible.