One man’s (milk)weed is another’s natural solution to oil spills
The humble milkweed may be a weed to most, but a company out of Granby, Quebec, is milking the plant for all it’s worth by developing a product for cleaning up oil slicks on land and water from milkweed fibers. Due to the fibers’ hollow shape – a unique feature in nature – and its naturally hydrophobic tendency, they repel water while absorbing more than four times more oil than the same amount of polypropylene materials currently used for spills.
This same hollow lightness of the fiber is what allows the attached seed of the milkweed to easily hitch a ride on the wind and propagate far and wide. According to Protec-Style president, François Simard, the company behind the absorbent kits, the fibers come naturally coated in wax, while its hydrophobic properties are very important for staying dry and light as the seed’s transportation system. “It’s very rare to see in nature like this,” says Simard.
To create the product, the fibers are mechanically removed from the pods and seeds, stuffed inside a series of polypropylene tubes which are made into kits, then placed on top of an oily surface. The company claims there are no chemicals used in the extraction process, while the fibers are untreated and perfectly absorbent the way they are. According to company tests, 155 g (5.7 oz) of milkweed fiber can absorb a total of 7 L (1.8 gal) of oil at a rate of 0.23 L (0.06 gallons) per minute, twice as fast as competing products made from polypropylene.
Oil is absorbed both between and inside the hollow fibers. “There’s a natural tendency for the oil to go into there,” says Simard. “You leave it on the water and the oil finds its way into the fibers, and prefers to grab onto the milkweed instead of staying on the water.”
Each kit can absorb 200 L (53 gal) of oil, and are removed from the surface once saturated. The company is currently supplying kits to Parks Canada, which fits the agency’s environmental stewardship mandate. The kits will be taken on boats and vehicles and used wherever petroleum products are found, like fueling areas.
To supply the company with its needed fibers, Encore3 is working with Quebec’s Ministry of Agriculture and Agriculture Canada, and has set up a cooperative of 20 farmers in the province to grow milkweed on 325 hectares (800 acres). Another 35 farmers are on a waiting list. It’s the world’s only industrial crop of milkweed, a plant indigenous to the region and grown without fertilizers or added irrigation. It’s also very efficient. According to Simard, each hectare (2.4 acres) will yield enough milkweed fiber to produce 125 kits, which translates into 25,000 L (6,604 gal) of oil cleaned up.
Quite possibly the happiest of all about this development are the monarch butterflies who inhabit southern Canada during the warm summer months, before departing on their 3,000 km (1,900 mi) flight to winter in Mexico (not unlike many of their human counterparts). The majestic orange and black butterfly only lays its eggs on milkweed, which is an important food source of the monarch caterpillar.
Monarchs have been in steep decline, which is partly due to the decline of milkweed from the spraying of pesticides on food crops. There’s even a movement to plant milkweed along the insect’s migration route, so a crop of milkweed in the region where monarchs breed is a welcome addition. At a 20 hectare (49 acre) milkweed plot in Quebec, there were so many monarchs it prompted drivers to stop. “We joked that we needed a ‘Monarch Crossing’ sign,” said Simard.
The company is also planning other uses for the milkweed fiber, including as an insulating material in winter jackets that Simard says is superior to goose down.
Source: Encore 3