The Use of Recovered Paint to Enhance the Performance of More-sustainable Concrete

Abstract

Some 20% of paint sold in western countries does not get used for its intended purpose. In time, much of this left-over paint ends up in land-fill as part of the household waste collection, at a significant economic and environmental cost. In New Zealand, Resene Paints Ltd has initiated a comprehensive product stewardship campaign to recover that paint before it enters the waste stream so that it can be recycled in applications which add value for the key participants in the recovery programme. Water-reducible paints exhibit many of the properties of concrete admixtures so one obvious use is to mix the recovered paint into concrete. While the usual concrete mix-design opportunity is to solve a particular problem by designing a mix that obviates that problem, the Authors in this instance are faced with a range of different mixes with unique properties and have sought performance tests to show the superiority of each PaintCreteTM mix for those applications. The commercialization has therefore required a detailed understanding of the properties of the new concretes, coupled with the commercial insights to determine where those properties might result in improved concrete performance, followed by suitable tests to prove those performance attributes to the satisfaction of the specifying Engineers or Architects.