An engineer from Washington State University has developed a new form of green, organic asphalt which can be manufactured using the cooking oil discarded by restaurants.

The new bioasphalt possesses the same physical properties as conventional asphalts made from petroleum, yet does not require the use of increasingly costly crude oil.

According to inventor Haifang Wen, assistant professor of Civil Engineering at the WSU Department of Civil and Environmental Engineering, his green bioasphalt “is as good as the old-school petroleum asphalt,” while also possessing the core advantages of reduced cost and heightened sustainability.

After four years of development in collaboration with a chemist which involved extensive “adjusting [of] the recipe,” the bioasphalt has passed a stringent array of stress tests and proven itself capable of withstanding the forces brought to bear by both compression and loading, as well as extreme temperatures as either end of the scale.

Haifang Wen

Haifang Wen

According to Wen bioasphalt is an emerging sub-industry of the green sector which harbours immense promise given the vast number of roads that modern economies need to function, as well as the increasing cost and scarcity of asphalt which is the result of rising petroleum prices.

“Building roads is a big investment in taxpayer money,” said Wen. “A one-mile road in a rural area costs at least a million dollars to build. With the waste cooking oil technology, we can reduce the cost of asphalt binder to under $200 per ton, making road building much cheaper.”

“Every year in the US we use about 30 million tons of asphalt binder for roads – more if you include shingles…it’s easily a multi-billion dollar business.”

The green asphalt industry has only hit its stride in the past decade, with scientists in various parts of the US now striving to develop low-cost organic road materials.

In Iowa, scientists have developed a form of corn-based bioasphalt which makes use of the byproducts of ethanol production, while in North Carolina the manure from piggeries is being used as an ingredient in a substitute for paving.

Wen said that industry is “very interested and eagerly awaiting the roll out of  (the) product,” especially given the introduction of President Obama’s 2012 Moving Ahead for progress in the 21st Century Act (MAP-21), which includes the need to make sustainability a part of America’s national infrastructure system.