In a small town about an hour north of Denver sits a nondescript warehouse where, decades ago, workers canned beans and tomatoes on an assembly line. Today, the chemists inside have much loftier ambitions. They’re aiming at a cheap, fast and sustainable way to make the stuff that makes our world, from sugars to fibers to plastics. A half-ton of their magical new cash crop, strawlike but infinitely sturdier, is stacked in bales covered with blue tarp.
It’s hemp, which also goes by “ditch weed” and, yes, “weed.” To Ed Lehrburger and his team of chemists at PureVision Technology, though, hemp is a veritable wonder material, a bioproduct to end all bioproducts, in a market that BCC Research estimates will be worth $473 billion by 2018. Not only is hemp versatile and incredibly strong, it can flourish in harsh conditions and need not compete with farmland or wood. And though hemp is indeed a form of cannabis, it has only trace amounts of THC, the element in marijuana that gets you high.
Only recently has space opened up for hempreneurs in the United States. For decades, hemp, like its psychoactive cousin, was a crop non grata in the U.S., and it still is, mostly. But in 2014, a provision in the federal farm bill opened room for universities and state agricultural departments to begin cultivating hemp; since then, at least 22 states have passed laws allowing commercial or industrial hemp programs for agricultural and research purposes, according to the National Conference of State Legislatures. Hempreneurs hope that Congress will pass legislation that would legalize the non-psychoactive form for cultivation.
Across the globe, hemp has long been used to make rope, clothes and building materials, while the plant’s seeds are a common dietary supplement. In recent years, scientists have also experimented with converting hemp oil into energy and discovered its bark is a cheap alternative to graphene that can be used to make supercapacitors. “Its versatility makes it a wonder crop,” says University of Connecticut professor Richard Parnas, who has conducted research on the potential of hemp as a biofuel. Through a biorefinery process it can be converted to sugar, pulp and lignin, which can be used to make plastics and paper products, says Lehrburger.
Hemp certainly has plenty of advantages over lumber, which is expensive and time consuming to process and not exactly environmentally friendly (most activities that involve chopping down forests aren’t). Compared with wheat, another hot biomaterial, hemp requires less water and pesticides, and can grow almost anywhere, so primary croplands can be reserved for growing food. Hemp can even flourish above the Arctic Circle, where crops like maize aren’t close to competitive, according to Thomas Prade, a researcher at the Swedish University of Agricultural Sciences.
But even if hemp could gain a toehold in a market still dominated by lumber, the revolution would have to overcome another serious obstacle: the cost of commercial mills, which experts say can be as much as $1 billion. PureVision claims it has created a much cheaper process, building on reactor technology that converts products like wheat straw and corn stover into pulp. If that technology works as well as Lehrburger says it does, it would be “a breakthrough,” says Ken Patrick, a scientist with the Technological Association of the Pulp and Paper Industry, a trade group.
Last year, PureVision got its hands on a tiny amount — less than a pound — of hemp waste, which it ran through a small-scale, specially designed converter to make pulp. Now that an entire growing season has passed, though, it was able to secure half a ton. This time the bamboolike stalks will be put through a pilot-size machine. Within the year, the refinery hopes to be processing 25 tons of hemp a day. Colorado Hemp Co., a paper producer, already has plans to move on-site — it would mean they could stop importing hemp pulp from Canada. Lehrburger is also partnering with an established industrial biorefinery in Oregon, which they hope to convert into a large-scale hemp processing plant by 2017.
But — and this is a huge but — all these efforts could easily turn out to be in vain, even if the pulping process works. Political tides could make the plant an outcast once again. “Over the next decade, the industrial hemp future could swing from zero to 10, or it could not budge an inch,” Parnas says. And, Prade adds, though there was a burst of interest in Sweden after the EU approved industrial hemp for the market, it has since cooled. It’s not economical to use for energy production, and forestry resources are still cheaper.
“People want it to be the super crop, but it’s still just one crop among others,” Prade says. “The key is if you have a multipurpose approach, you can get more out of it than most.” And that’s exactly what biowaste processing can offer.
(Story source – Meghan Walsh, picture credit – © Jim Craigmyle/Corbis )