Michigan State University Extension educator Charles Gould is working on an idea that may help turn manure into environmentally friendly composite products for the construction industry.
Gould has a vision for new lines of composite materials that use a combination of plastic and manure fibres, instead of the wood that comprises current fibreboard and other building supplies, to develop products for use in the construction of everything from playground equipment to homes.
“There is a limited land base for manure application. Keeping Michigan’s livestock industry strong and viable means we have to find a home for the manure generated by these farms,” Gould said. “Why not make products from manure that benefit society, add value to the farming operation and at the same time, fit nicely into a sustainable manure management system?”
Farmers looking for alternatives to land application can choose to compost manure. Composting reduces its volume, makes it a more stable fertilizer source and eliminates odour. Another option is to use an anaerobic digester, which breaks manure solids down into a sterile organic fibrous material and captures methane gas that can be used to produce electricity for the farm or sold to utility companies.
After reading an article about how another university’s biological composites lab successfully combined the fibrous material from a digester with plastic to create composite materials, Gould realized the possibilities for Michigan.
With a grant from the Michigan Biomass Energy Program, Gould and forestry professor Laurent Matuana hired undergraduate student Alex Cook to develop two prototype products. Those products included a digester fibre/plastic composite product that could be used as decking and a medium-density fibreboard. Then they were tested and compared to similar items made using wood fibre. The products made with fiber from a digester passed with flying colours, meeting or exceeding industry standards for properties such as strength, stiffness and internal bond.
The digester fibre/plastic decking product performed better in tests against similar decking products made with wood/plastic. When two composite types were compared, the digester fibre/plastic decking product had properties that were superior to those of the wood product, including a darker colour which potentially could be more resistant to ultraviolet rays.
During the production process, the fibres intertwine and increase the strength of resulting composites. This offers an advantage in areas such as load-bearing capacity or material strength.
“The properties of the medium-density fibreboard met or exceeded standard requirements,” said Matuana. “We have shown that value-added products can be successfully manufactured from digester fibres.”
Gould has already approached managers at two western Michigan home improvement retail chains to ascertain their feelings about carrying digester fibre/plastic decking or medium-density fibreboard made with the fibrous material from a digester. “They indicated a willingness to purchase the product even though it was made out of fibre once found in manure because they perceived the products to be green,” he said.
The most common question asked was about odour, Gould said. Neither the fibre/plastic decking nor the medium-density fibreboard emits an odour.
Source: NetComposites, 2007-02-04.