The agricultural and forest industries both produce residues or waste streams that have little or no economic value. The challenge that remains for agricultural and forestry residues is how to best utilize this material for maximum efficiency and economic profit. While at LSU, Dr. Todd Shupe received $250,000 from the USDA to examine the suitability of a rapidly-developing new technology known as continuous microwave-assisted liquefaction to convert this under-utilized material to bio-polyols for the production of spray-foam insulation. Liquefaction is a process that can be used to dissolve biomass in an organic solvent (also called a reagent solvent) at moderate temperatures (120 to 250 ºC) with or without acid catalysts (Hse et al. 2011; Pan 2007; Pan et al. 2012). Liquefied biomass can be concentrated and used as a raw material for other value-added products such as polyurethane foam, epoxy resin or phenolic resin depending on the reagent solvent used in the liquefaction (Pan 2007). “Our application of microwave technology to the liquefaction process has received a U.S. patent (#8,043,399) and has been shown to dramatically improve the liquefaction rate, shorten the reaction time, lower operational temperature, and use less chemical input as compared to traditional liquefaction reactions,” Todd Shupe says, (Hse et al. 2011).
Spray-foam insulation is growing in popularity as a type of insulation for residential and commercial housing. Spray-foam is a substitute for traditional fiberglass insulation. The chemical agent is stored in canisters and sprayed with a special application device; it then expands and dries, forming a barrier. The advantage of foam insulation is that it expands and leaves no gaps as is the case with typical fiberglass insulation. Therefore, there are no pathways for air to escape – thus an efficient vapor barrier is established. The foam also prevents the buildup of moisture, lowering the incidence of mildew and mold problems, and makes it more difficult for insects and other pests to burrow into a building. Says Todd Shupe, “Spray-foam insulation is recognized as an important part of the wall component in ‘green’ buildings, and also is one of the fastest growing areas in building products.” These advantages and the “green” aspect of foam insulation can be rolled into one with the development of spray-foam insulation from liquefied biomass to attain a new renewable and sustainable product.
The higher cost of spray-foam insulation has slowed its advancement in the residential housing market. The low cost of the feedstock and the proposed experimental parameters for this study should help this product gain market share. The development of “green” spray-foam insulation from liquefied biomass will promote economic development and diversification. In addition to substantial energy cost savings, biomass-based spray-foam has much better biodegradability compared to petro-based foam insulation, which will benefit the environment if this material is landfilled. Dow, Oak Ridge National Laboratory (ORNL), and design-build firm, Paramount Metal Systems, have converted a 50-year-old building at ORNL into a state-of-the art, energy-efficient research facility. Initial test results show a 75 percent reduction in heat flow, resulting in a projected 75-80 percent monthly savings in energy costs (Spray Foam 2013).
A viable bio-based spray foam industry is likely to lead to economic development opportunities due to the growing interest in spray foam insulation and increasing consumer demand for green products. The successful utilization of agricultural and forestry residues will benefit the agricultural producers, wood processing industries and forest landowners. These sectors combined contributed $4.1 billion to the Louisiana economy in 2013 (LSU AgCenter 2014). The state has more than 14 million acres in forests and another approximately 2 million acres in agricultural plant commodities. “Most of this land is located in rural communities and consequently, this project has great potential for rural economic development in these areas,” says industry expert Todd Shupe.
Agricultural commodity prices are depressed from their recent historical highs and most experts predict that situation to continue. As expenses continue to rise, profit margins for farmers are therefore smaller and there is keen interest in adding value to residues (Guidry 2014). Louisiana has approximately 238,000 workers (9.4 percent of the labor force) employed full-time or part-time in the food and fiber sections (LSU AgCenter 2010). Workers employed in Louisiana in forest products manufacturing earned $750.4 million in 2013 (LFA 2014). Therefore, any improvement or advancement in these industries can have a great multiplier effect. Increasing value-added processing of agricultural and forestry residues is important to the viability of rural economies in Louisiana. Todd Shupe further notes that the wages and salaries paid to hire farm workers, as well as the profits earned by farmers, typically return back to the local economy through household spending – thereby helping rural businesses (LSU AgCenter 2010).
In addition to rural economic development related to the feedstock, there is also economic development potential related to the product – spray foam insulation. The insulation market in North America was an $11 billion dollar market in 2012 and growing each year. Spray foam comprises 9 percent of that market is the fasting growing segment of the market, estimated at an annual growth rate of almost 5 percent. There is a rapidly growing “green” market for numerous goods and services. This is particularly evident in the housing market as consumers are increasingly demanding that lumber that is used for new home construction be harvested from a certified managed forest (Green Home 2014). Consumers are demanding green products for their housing, transportation, energy, food and cosmetics. The common belief years ago, as Todd Shupe remembers, was that people would not pay extra for green products and while they may remain true to some extent, there is a growing market that is keenly interested in green products. These markets are particularly evident in more affluent, urban areas.
Our highway and interstate system is a critical component of our nation’s infrastructure and economy. These are essential for the transportation of goods and services, emergency responders, commuting to work and family vacations, says Todd Shupe. It is imperative that our highways provide safe travel for all. Highway guardrails, as you can see, are an important safety component of our highways. They typically consist of a galvanized metal rail, treated wood block, treated wood post and fasters. However, steel blocks and posts can also be used.
Chromated copper arsenate (CCA) has a long history as an EPA-approved wood preservative for numerous applications such as posts and blocks used in the guardrail assembly. “Numerous independent studies have shown that CCA is an environmentally-safe wood preservative and has very minimal leaching,” writes LSU’s Todd Shupe, a wood sciences expert and former lab leader.
Dr. Kenneth Brooks wrote in Pressure Treated Wooden Utility Poles and Our Environment, “pressure-treated wood utility poles pose no greater risk to the environment than growing the wheat used to bake your next loaf of bread, and present far less personal risk than driving to your local grocery store to purchase that bread.” Similarly, Dr. Paul Morris has written, “There are environmental risks associated with everything we do and with all of the material used to construct utility structures. For instance, the leaching of zinc from steel utility poles.”
The Treated Wood Council commissioned an independent study of the environmental impacts associated with the national production, use and disposition of treated wood and galvanized steel highway guard rail posts using life cycle assessment (LCA) methodologies. The results for treated wood compared to galvanized steel guard rail posts were significant (© Treated Wood Council, 2013).
- Less Energy and Resource Use: Treated wood highway guard rail posts require less total energy and less fossil fuel than galvanized steel highway guard rail posts, Todd Shupe commented.
- Lower Environmental Impacts: Treated wood highway guard rail posts have lower environmental impacts than galvanized steel highway guard rail posts in five of six impact indicator categories assessed: anthropogenic greenhouse gas, total greenhouse gas, acid rain, ecotoxicity, and smog-causing emissions.
- Offsets Fossil Fuel Use: Reuse of treated wood highway guard rail posts for energy recovery will offset the use of fossil fuel energy and thereby reduce greenhouse gas levels in the atmosphere.
“Here’s the bottom line,” says LSU’s Todd Shupe. “CCA-treated wood is a critical part of our nation’s infrastructure and economy. It is safe for the environment and has a long history of EPA approval for both the environment and human exposure.”
The alternatives (steel and concrete) are not renewable and require more energy to produce than CCA-treated wood, he adds. Last but not least, CCA-treated wood is more cost effective than the alternatives. CCA-treated wood is good for the environment and the economy!