Finishing - Reducing the Carbon
Since the 1970’s powder coating has revolutionised the Finishing Industry with its environmentally friendly application which eliminates the use of solvents or VOC’s (volatile organic compounds). With various types of modern resin systems and cross-linking compounds now used, the resultant finishes are extremely robust. Over the years since its commercial introduction, the reduction in energy usage has been driven primarily by cost saving, today the emphasis has shifted to process carbon reduction.
Already an environmentally friendly finishing process, carbon reductions can be made through efficiencies in energy usage, product packaging and transport. Members of QUALICOAT UK & Ireland, who represent the majority of the architectural powder manufactures, pretreatments system suppliers and coaters in the UK are currently reviewing ways of how this can be achieved.
Plant used for powder coating plays an important step, the more modern the plant the more efficient the running costs are with the associated reduction in carbon emissions. Modern plant also offers a high degree of powder reclaim in the powder spraying, so powder which is not attracted to the coated product is immediately reclaimed and is directed back to the spray booth.
Not all members can afford to replace plant when new designs become available, indeed the carbon costs of such a replacement could take some time to recuperate making the change unnecessary. Plant can be modified and it is this best practice that is the way forward.
The main energy consumption in architectural powder coating is the heating of the ovens where the powder on the surface of the aluminium melts and cures to form the finish. Curing ovens use gas or electricity to run up to 200ºC with modern plants opting for electricity. With gas prices increasing it is likely that we will see some conversions over to electricity in the future. Infra-red ovens can be more efficient to cure surface coatings, but, with aluminium extrusion, it is crucial that the aluminium substrate reaches the desired temperature to ensure a good cure and adhesion, there is more work to be done in this area before it becomes a viable option for architectural coatings.
Low cure temperature powders, or Low-E powders, are now becoming available so that curing ovens can be run at lower temperatures, typically 150ºC to 170ºC. At the moment the range of colours is limited, but these products could quickly become mainstream and become specified by architects.
Where possible, packaging materials used on delivered extrusion is reused to line stillages and protect finished profile. Recycled protective materials are used to interface profiles when stacked together to ensure surface protection in transport, where possible. Whilst steel or aluminium delivery stillages have been reused through the supply chain from extruder to fabricator, work is being undertaken to reduce the carbon impact of packaging. Containers that carry powders and pretreatment chemicals are currently being collected by suppliers and either recycled or reused.
Transport between extruder, powder coater and fabricator is constantly under review to ensure ‘carbon miles’ are reduced to a minimum. The introduction of electric delivery vehicles will further enhance carbon reduction. Some aluminium systems companies now combine their design of systems with both extrusion and finishing on the same site.
As UK & Ireland members are working together, reductions in carbon will continue across the sector which will ensure that powder coatings continue to be the number one choice for specifiers.
Possibly the most enduring sustainable issue is that a QUALICOAT specification will ensure that an architectural powder coated project is correctly applicated to last, that in itself reduces carbon impact on our environment.
The next QUALICOAT UK & Ireland members meeting takes place on 19th October 2021, at the Arden Hotel & Leisure Club, Solihull , please contact the General Secretary, Jan Lukaszewski, via the QUALICOAT UK & Ireland website, should you wish to attend. For details on the availability of various colours and finishes contact any QUALICOAT UK & Ireland member for more information. For updated information about the use and specification of QUALICOAT in the UK and Ireland, please visit the UK & Ireland Association website at www.qualicoatuki.org
QUALICOAT UK & Ireland with offices based in the Midlands is the National Association for QUALICOAT approved companies. QUALICOAT is a global quality label organisation committed to maintaining and promoting the quality of lacquering, painting and coating on aluminium and its alloys for architectural applications.
Please browse our website and should you have any questions about architectural powder coatings and the correct specification, please contact one of our local members or phone our office on the number below.
QUALICOAT UK & Ireland Chairman