Location: Forage Seed and Cereal Research
Title: Elemental concentrations in Triticale straw, a potential bioenergy feedstock Authors
Submitted to: Energy and Fuels
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 10, 2011
Publication Date: January 25, 2011
Citation: El Nashaar, H.M., Banowetz, G.M., Peterson, C.J., Griffith, S.M. 2011. Elemental concentrations in Triticale straw, a potential bioenergy feedstock. Energy and Fuels. 25:1200-1205. Interpretive Summary: Triticale is a small grain that is produced on marginal land and used primarily for animal feed. Straw produced during grain harvest has potential for use as feedstock for bioenergy production. Elements that are present in other cereal grains cause problems in the use of thermochemical approaches to convert straw to energy, but little is known about the elemental composition of triticale. We analyzed the elemental composition in eight different varieties of triticale grown in western Oregon to determine whether the varieties differed in the amount of the elements they accumulated during their growth. These analyses showed that some varieties consistently contained lower quantities of silica and chloride, two elements that cause problems in thermochemical conversion processes like combustion and gasification. Our elemental analyses also enable us to estimate how much nutrient value is removed from the production system when straw is harvested.
Technical Abstract: Triticale (X Triticosecale Wittmack) is produced on more than three million ha world wide including 344,000 ha in the USA. Straw resulting from triticale production could provide feedstock for bioenergy production in many regions of the world, but high concentrations of certain elements, including silicon (Si), potassium (K), and chlorine (Cl) that are characteristic of cereal straws present challenges for utilization in thermochemical conversion technologies. There is also concern regarding the long-term sustainability of residue removal because straw harvest removes macro- and micronutrients from crop production eco-systems and leaves soil vulnerable to erosion. We quantified the concentrations of Si and nineteen other elements in chaff, grain, leaves and stems harvested from eight triticale cultivars grown in western Oregon and found significant genotypic variability in the concentrations of certain elements. On average, harvest of the whole triticale plant removed 4.8 g nitrogen (N), 5.3 g phosphorus (P) and 80 g K kg-1 of straw. Harvest of the grain alone removed 1.2, 3.1, and 4.8 g of N, P, and K, respectively. Silicon content ranged from 17,583 to 37,163 mg kg-1 among the cultivars. Straw from the cultivar ‘Taza’ contained the least amount of Si. The range of variability in the concentrations of some of the elements suggests the possibility for genetic improvement for utility as bioenergy feedstock as well as for nutritional quality where triticale is used as a feed grain. Biomass with reduced amounts of elements that impact thermochemical conversion processes would enhance the potential for bioenergy production from this non-food crop.