Dec 3 2019
Annually, $5 billion is spent by the United States to repair damages to road infrastructure caused by winter snow and ice control operations and the use of conventional deicers. A research team from Washington State University (WSU) is creating a more sustainable solution using grape skins and other agricultural waste.
Xianming Shi first thought of using biotechnology to derive deicer additives out of agricultural waste materials several years ago when tasked by the Alaska Department of Transportation to develop locally sourced and performance-enhanced brine formulations for anti-icing. Image Credit: Washington State University.
The scientists, including graduate student Mehdi Honarvar Nazari and Xianming Shi, associate professor in Civil and Environmental Engineering, demonstrated that their deicer, including grape extract, outclassed widely used deicers, such as road salt and what is believed to be a more eco-friendly blend of salt brine and beet juice.
The study outcomes have been reported in the Journal of Materials in Civil Engineering (December 2019 issue).
Annually, about 27 million tons of sodium chloride, generally called road salt, is used on U.S. roadways for winter maintenance. The chlorides do not break down in the environment and could give rise to long-term environmental hazards. Commercial deicers usually include chemicals that are corrosive toward concrete, metals, asphalt, and are hazardous to marine species.
Beet juice has turned out to be a standard additive used by cities and highway departments to improve the deicers’ performance while decreasing their corrosive effects. However, when beet juice makes its way into water bodies, it can lead to oxygen depletion and pose a risk to marine organisms.
With the aim of creating a greener additive, the WSU scientists extracted chemicals from waste grape skins via chemical degradation and natural fermentation. According to Shi, the innovative process to produce the formula does not generate any kind of waste.
The scientists discovered that the grape extract-based solution melts ice quicker than other deicers and considerably reduces the damage to asphalt and concrete, the two most universal materials used in roads and bridges. The solution is also less hazardous to adjacent water bodies.
We delivered a more sustainable solution because we’re introducing less chlorides into the road operations and are achieving comparable or better performance. It’s one step in the right direction.
Xianming Shi, Associate Professor, Civil and Environmental Engineering, Washington State University
Initially, Shi planned to use biotechnology to extract deicer additives from agricultural waste materials a number of years ago when the Alaska Department of Transportation tasked him to create locally sourced and performance-improved brine formulations for anti-icing. His team has also effectively applied this technology to waste sugar beet leaves, peony leaves, dandelion leaves, and waste from grapes and apples.
The beauty of this approach is that it allows us to diversify. We can use this same platform technology in different regions of the country but choose a different agricultural product, depending on what source of waste is available.
Xianming Shi, Associate Professor, Civil and Environmental Engineering, Washington State University
The research received support from the Washington Department of Transportation, the National Science Foundation, and the U.S. Department of Transportation.