Bioenergy Applications

Objective 2. Investigate and demonstrate the use of innovative bioenergy technologies that promote the utilization of invasive plant biomass as a fuel source

The goal of Objective 2 is to investigate and demonstrate innovative bioenergy technologies that promote the use of saltcedar and Russian olive biomass as a new raw materials or feedstocks for bioenergy generation. Saltcedar and Russian olive are hugely problematic invaders that presently infest at least one million acres within the Missouri River Watershed region and are virtually untapped sources of biomass. We propose that the tons of mostly herbicide-treated biomass, much of which has simply been left in piles throughout the region, can be processed on location by producers and used as a new, free bioenergy source.

As a preemptive and precautionary step, the Missouri River Watershed Coalition (MRWC) began conducting tests on saltcedar (Tamarix spp.) and Russian olive (Eleagnus angustifolia) as potential bioenergy sources in early 2010. We collected samples of herbicide-treated and untreated saltcedar and Russian olive biomass and commissioned Yankee Pellet Mill, Inc. and Keystone Laboratories, Inc. to perform herbicide toxicity and preliminary feasibility tests on the samples. This action was taken to ensure that herbicide-treated biomass does not contain high levels of toxic herbicide residues, can be safely used as a bioenergy source, and has a heat value/energy content competitive with other vegetative materials currently used as fuel sources. Results showed BTU (calorific value) and ash content levels for both species fall within the "acceptable" BTU range for bioenergy generation.

Objective 2a. Innovative technology transfer and demonstration of on-site conversion of saltcedar and Russian olive biomass to usable bioenergy products

The MRWC and our project partners will sponsor and conduct several workshops in three or four of the MRWC states to demonstrate on-site conversion of saltcedar and Russian olive biomass to bioenergy products. The goal of these two-day events is to demonstrate the effectiveness, affordability, usefulness, and utility of biomass conversion in the field and to transfer innovative bioenergy technology and resources to land managers. These workshops will also promote the exchange of information and interaction between land managers and private sector companies (local and national), which we hope will encourage the private sector to adapt current technologies to accommodate these promising new sources of biomass feedstock. Pelletization, bio-brick production, and a few other bioenergy generation technologies are currently available, but have not been readily applied to invasive plant biomass conversion. The MRWC plans to purchase portable biomass conversion/bioenergy generation equipment (pellet mill, hammer mill, three-phase power generator, gasifer, and transport trailer) that can be showcased at these workshops as well as be made available to producers within the Watershed to achieve conservation management goals on their properties.

Objective 2b. Testing saltcedar and Russian olive for feasibility as new feedstock/biomass sources for bioenergy generation

The MRWC will continue feasibility tests on saltcedar and Russian olive biomass, focusing on the most common and currently available bioenergy generation technologies: pelletization, bio-brick production, and others. These tests, to be conducted in late 2010 and 2011, will build on our preliminary feasibility tests but will also address more specific bioenergy variables, such as variability of product by site, material handling and processing needs, and so on. Follow-up test results will be reviewed and interpreted for the MRWC by our project partners and academic and industry experts, and information will be disseminated by the Center for Invasive Species Management in a timely fashion at our workshops and via our communications networks, outreach activities, and publications.

Progress Update, July 2012

In July and August 2011, Russian olive and saltcedar samples were collected from five sites in Montana and Wyoming. Feasibility tests were conducted on the samples to determine BTU levels generated per pound of material, ash content, volatile matter content, and moisture content. The test results were then compared to data from forestry species traditionally used in bioenergy applications. Comparisons of the data indicate that while the BTU levels of both Russian olive and saltcedar are relatively close to those of the forestry materials, the ash content level of saltcedar is considerably higher than the desired levels of 0.5–1% for use in commercial wood pellet markets.

Additional samples of Russian olive and saltcedar are currently being tested to determine whether elemental composition of the plant material may negatively impact its potential value for use in bioenergy applications. The presence of inorganic elements such as sulfur, sodium, chlorine, potassium, and alkali have shown to be troublesome in other biomass applications, and may indicate specific challenges for bioenergy utilization. Upon completion of the elemental composition testing, the data will be evaluated by combustion specialists to assess the potential of Russian olive and saltcedar biomass for bioenergy applications or conversions.

Ongoing efforts concerning the bioenergy investigation will continue in 2012, and will be driven primarily by the recommendations of industry experts. We expect that upon receiving additional bioenergy test results and analysis, along with input from industry experts, we will be able to develop recommendations regarding the most effective methods for utilizing Russian olive and saltcedar biomass in bioenergy applications.