Rice waste product makes for tougher roads

NAGANO, Japan, Jan. 16 (UPI) -- A waste product from rice has been used by scientists in Japan to produce surfacing materials that make for quieter, more resilient roads.

Roads made using this method absorb noise better, drain faster and are less susceptible to extremes of temperature than traditional road surfaces, according to Minebea Corp. of Nagano, Japan.

The new traffic surfaces contain rice bran, the layer that separates rice grains from their husks, reports Richard Butler in the current issue of Chemistry and Industry Magazine.

The bran is usually disposed of in landfill sites or used as cattle feed. But when the rice bran is mixed with resins, the result is a hard material that is light, friction-resistant and porous.

Mixtures of the material can be added to asphalt and aggregate to make a long-lasting road surfaces. Minebea's tests suggest the rice bran-based surfaces can absorb around 25 percent more noise than aggregate and asphalt roads or surfaces with glass fibers added.

This could make the surface popular in built-up areas or on major roads close to residential areas, Minebea said.