South Dakota
Mines researchers are part of a new $6 million grant from the National Science
Foundation (NSF) to develop bioplastics for use in agriculture over the next
four years.
The project, called Bioplastics
with Regenerative Agricultural Properties, or BioWRAP, includes a research team at Mines working alongside a principal
investigator at Kansas State University and researchers at the
University of Nebraska-Lincoln.
Traditional specialty crop production, like organic
agriculture, often use petroleum-based plastic sheets to cover the ground.
Conventional plastics leave microplastic residues which contaminate the
environment and increase stormwater runoff. This project aims to reduce the use
of plastics, herbicides, fertilizers and associated environmental impacts in
agricultural production by creating an all-in-one bioplastic system that can
better manage weeds, add nutrients to soils, improve soil and plant health, and
save water.
“This is exciting research to see unfold on campus
as it can have a major benefit for farmers in South Dakota and across the
nation. Kudos to Mines researchers for seeking solutions that are both cost
saving for our ag producers and healthy for the environment,” says Mines
President Jim Rankin.
BioWRAP researchers aim to create spray-on
biodegradable plastic that can be administered to croplands. The product would
be locally produced from natural materials like corn stalks, hay, or chicken
feathers and infused with nutrients and microbes that will add to soil health
as the covering degrades. The goal is to create a material with a smaller
carbon footprint than the traditional plastics used commonly in organic
agriculture.
“This project uses the natural resources we have
right here in South Dakota to launch a new era of biodegradable and sustainable
materials that help the agricultural economy by adding value to local crops
while increasing soil health and crop yield,” says David Salem,
Ph.D., who leads the Composite and Nanocomposite Advanced Manufacturing - Biomaterials (CNAM
Bio) Center at South Dakota Mines and a
co-principal investigator with BioWRAP. Salem also plays a leading role at
Mines in collaborative research with the new POET
Bioproducts Institute.
Mines is contributing to the project in four main
areas:
Water Seeps In, Weeds Stay
Out
Researchers are working to create a slurry mixture
of starch-based biopolymer and degradable bioplastic pebbles. Once sprayed onto
the ground, the covering would let water in but keep weeds from growing. Chris Shearer,
Ph.D., is an associate professor of civil and environmental engineering at
Mines who brings an expertise in concrete as a co-principal investigator on the
project. “This product is made of biodegradable pellets and a binder that will
behave like pervious concrete,” says Shearer. “There is a lot of crossover
between the two materials.” Shearer will work to measure the properties of
various BioWRAP mixtures to maximize the benefits of the final product.
Keep it Local: Help the
Environment and Boost the Ag Economy
Heidi
Sieverding, a research scientist in the Department of Civil and Environmental
Engineering at Mines, is one of the co-principal investigators on BioWRAP
focusing on understanding the environmental impact of the new product. “To make
it sustainable, we can’t be buying a bioplastic from a factory overseas; we
have to make it right here,” says Sieverding. “We want to find a way to
sustainably make bioplastics in small towns and communities and use them to
boost rural economies.” Sieverding notes that a product like concrete is always
made from local materials – close to where it’s needed. “We can manufacture biodegradable
plastic locally in the same way we make concrete,” she says. Farmers could bring
crop residues to local biorefineries for processing and bring bioplastics back
to the fields to use. Sieverding says this sort of change would need to be done
in conjunction with local farmers in a grassroots effort to make sure it benefits
producers. She notes the creation of the ethanol industry, which has helped
farmers find new value for their crops, is one example of a way this product
could move forward.
Making a Home for Good
Bacteria: Imbedding Nutrients in the Soil Cover
“We are
working to create a tunable bioplastic,” says
Rajesh Sani, Ph.D., professor of chemical and biological
engineering and chemistry, biology, and health Sciences at Mines and a
co-principal investigator with BioWRAP. Sani also leads NSF funded project called BuG ReMeDEE which is producing bioplastics
from the greenhouse gas, methane, in collaboration with CNAM-Bio. Sani and the researchers
on his team aim to create and functionalize bioplastics that are the perfect
home for nitrogen fixing bacteria. These indigenous bacteria will live on the
biodegradable plastic compound and give carbon and nitrogen nutrients to the
soil throughout the crop cycle as the bioplastic degrades. If widely
implemented, this has potential to save billions of dollars in fertilizer costs
every year. “This is a very ambitious goal and if we make this happen, it will
revolutionize the agriculture industry,” says Sani. “We are trying to target
several things: control the weeds, control the soil temperature and humidity
and increase soil health over time as these bioplastics will be nutrient for
the soil and plants.”
Mines Patent-Pending Biodegradable
Bioplastic
One of the key
ingredients of BioWRAP is a revolutionary way to efficiently convert ag byproducts,
like corn stalks, into an environmentally-friendly biodegradable plastic.
During her doctoral research at Mines, Tanvi Govil discovered a microbe that
eats corn stalks and produces bioplastic without costly pre-treatments
previously required to create this material. This patent-pending breakthrough
technology is thanks to research funding from the CNAM-Bio Center, supported
through the South Dakota Governor’s Office. “This BioWRAP project gives us a
chance to apply this new degradable bioplastic we developed at Mines as
environmentally friendly mulch films,” says Govil, who will complete her Ph.D.
this spring and continue her post-doctoral research at Mines through support
from the BioWRAP project, while continuing to contribute to the core goals of
the CNAM-Bio Center.