Industry Innovations

A 100% recyclable construction material

The global economy has made great strides in becoming greener, but there are still massive inefficiencies in the way we deal with our waste materials, including construction material which produces 33 per cent of the EU’s generated waste according to a recent Eurogypsum report. 

As the report highlights, gypsum is one of many materials we could be using more efficiently because the chemical processing to make plaster is entirely reversible.  Gypsum becomes plaster when it’s dehydrated, and on the addition of water it becomes gypsum again, like a cake that turns back into eggs and flour once it cools down.  Because of this unique chemistry and the fact that the process does nothing to affect quality, gypsum is 100 per cent recyclable, making it unlike any other construction material.

In theory, plaster production could become the first truly circular economy.  However, theory and reality have so far failed to intersect.  Some gypsum is injected into the economy fresh from quarries around the world, and the rest is synthesised as a by-product of flue gas desulphurisation, a process that takes place at some coal-fired power plants.  Current demolition methods cause too much contamination to recover a demolished building’s gypsum in isolation, so is a true ‘circular economy’ possible even with the most recyclable material in construction?

Gypsum-to-Gypsum

Siniat was recently one of 16 industrial and academic partners in seven countries involved in the Gypsum to Gypsum project, a three year EU Life+ initiative aimed at changing the way gypsum waste is treated. 

The main objective of the project was to achieve higher recycling rates of gypsum waste, helping to achieve a resource efficient economy.  We’ve recognised that closed loop recycling of gypsum products will only happen if buildings are systematically dismantled instead of demolished, allowing waste to be sorted on site to avoid mixed and contaminated waste.

Since the project started in January 2013, Gypsum to Gypsum has defined the baseline position and advanced new methodologies for the audit and deconstruction of building elements for the recovery of materials.  Siniat has contributed industrial knowhow in defining state-of-the-art plasterboard recycling, assisting with pilot trials dosing reclaimed material at up to 23%.

Although Siniat products already contain high levels of post-consumer recycled material, we fully recognise that more is going to be required to meet EU aspirations for resource efficiency in the built environment.  The next revision of the EU Landfill Directive is expected to further drive waste streams from end of life buildings into closed-loop recovery.  The experience and learning gained by Siniat through participation in the EU supported project provides a head-start in responding to the coming challenge.

The entire country needs to adopt this way of thinking if we’re to meet our emissions targets, now is the time for the supply chain to work together. Closing the loop would mean that materials aren’t just cycling and recycling the process once or twice, but are indefinitely locked in with no need for top-up injections of new materials.