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Biomass is one of the most feasible renewable alternatives to fossil fuels. Given this fact, this study aims to demonstrate that buriti fruit wastes (pits and husks) are a promising new feedstock for bioenergy production via thermochemical conversion. To evaluate the suitability of buriti pits and husks for bioenergy generation, their physicochemical properties, performance indices, and pyrolytic behavior were evaluated based on ultimate, proximate, and calorimetry analyses, emission factors, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM images), energy dispersive spectrometry (EDS), thermal analysis (TG/DTG/DSC curves), and devolatilization index (DI). In addition, the mineral and metal contents were quantified by inductively coupled plasma optical emission spectroscopy (ICP-OES). The buriti wastes exhibited low ash (< 3.2%) and moisture contents (< 13.0%), a high heating value (HHV) of 16.11–20.61 MJ kg−1, negligible nitrogen content (< 1.2%) and sulfur (non-detected), and lower carbon dioxide (1236–1244 g kg−1) and nitrogen oxides (3.32–3.95 g kg−1) emission factors than those of reference fuels. The physicochemical properties of buriti pits and husks were consistent with those of other agroforestry and agroindustrial biomasses. The DI of 1.47 and 5.27 × 10−8 mg min−1 °C−3 (or 0.35 and 1.17 ×10−6% min−1 °C−3) of buriti pits and husks, respectively, revealed the main difference between the thermal performance and suitability of buriti pits and husks for the partial or total replacement of fossil fuels. The buriti wastes displayed exceptional performance under direct combustion, and a comparison of buriti pits and husks highlighted the remarkable suitability of buriti pits for pyrolysis, probably due to the oleaginous nature of the material. • Buriti pits and husks were assessed for physicochemical and thermal properties. • Buriti wastes employment reduced 38.00% of gaseous emissions when compared to coal. • Buriti seeds presented a suitable pyrolytic behavior than reference fuels. • Buriti husks presented higher fixed carbon content compared to buriti pits. [ABSTRACT FROM AUTHOR]

Highlights • Cordgrass state average yields are 4.9 t/ha with break-even prices of $274/t. • Switchgrass state average yields are 5.8 t/ha with break-even prices of $271/ha. • Miscanthus yields average 4.0 t/ha with break-even prices of $272/t. • Average yields are lower than other parts of the U.S. and Canada. • Average break-even prices are expensive limiting investment attractiveness. Abstract Large scale industrial biomass efforts, whether in pursuit of cellulosic bioethanol, or combustion, will require amounts of feedstock in excess of available crop residues, leading to considerations of purpose grown agricultural biomass. This study determines the yields and break-even prices of perennial grass biomass crops in the state of North Dakota using bioeconomic GIS-based simulation modelling to address the uncertainty surrounding investments in biomass feedstock, particularly in northern climates and the Northern Great Plains. Cordgrass state average yields are 4.9 t/ha with break-even prices of $274/t. Switchgrass state average yields are 5.8 t/ha with break-even prices of $271/t. Miscanthus yields average 4.0 t/ha with break-even prices of $272/t. Average yields are lower than other parts of the United States and Canada, with Miscanthus suffering from significant potential winterkill. Average break-even prices are expensive, limiting the attractiveness of industrial scale investments in perennial grass biomass in the Northern Great Plains and other northerly climates. [ABSTRACT FROM AUTHOR]

Environmental concerns and energy security have led to growing interest to second-generation biofuel production from non-edible feedstock such as switchgrass. In this article, sustainable and ecological indicators are introduced to evaluate the candidate locations efficiency for switchgrass cultivation. To optimize the candidate locations, a novel data envelopment analysis (DEA) cross-efficiency model is proposed which attempts to maximize output worst-cases of all candidate locations. Moreover, in order to consider both mean and standard deviation of candidate locations cross-efficiencies, a new ranking measure is presented. The performance of proposed model is investigated in comparison with several models through a real case study in Iran. The efficiency values of Iran provinces are calculated by several DEA cross-efficiency models. The numerical results show that proposed model manages to evaluate the candidate locations efficiency more moderate than other models. Besides, the standard deviation of cross-efficiencies for this model are lower than that of other models. The obtained findings from introduced DEA model reveal that based on the defined ranking measures, Khouzesan and Fars provinces are non-dominate locations for switchgrass cultivation. [ABSTRACT FROM AUTHOR]

Ongoing severe drought and increased demand for freshwater by municipal and industrial sectors have reduced the freshwater availability for agriculture in the far west Texas region. The region has enormous potential for developing alternative water sources for a bioenergy crop that requires less water and can grow on saline soils. In addition to improving farm income, this can help in producing 137 billion liters of bio-based transportation fuels goal set by the U.S. Congress by the year 2022. This study evaluated switchgrass ( Panicum virgatum L.) performance under treated urban wastewater irrigation on salt affected soils amended with gypsum and polymer using soil columns prepared from a salt affected land over six years under greenhouse conditions that mimicked the climatic conditions of the study region. Results indicated that switchgrass produced appreciable biomass even under highly saline and sodic conditions. Qualities of biomass under treated urban wastewater were comparable to that produced under freshwater irrigation. Expectedly, soil salinity increased with time at a greater rate under wastewater irrigation than freshwater. Soil SAR values were below threshold when adequate Ca was available to counter sodicity. In addition irrigation with treated wastewater improved nitrogen and potassium status in the root zone. This can reduce of cost of fertilization and increase farm profitability. [ABSTRACT FROM AUTHOR]

Marginal and degraded lands are expected to be important resources in the production of biofuel feedstocks in order to avoid real or perceived competition with food, feed and fiber production. Globally, there are millions of hectares of salt-affected land available for lignocellulosic feedstock production. Greenhouse experiments determined the effects of irrigating with water having different levels of salinity and sodicity on seedling emergence, plant growth, and cation balance in plant tissues in several populations of switchgrass ( Panicum virgatum L.) and prairie cordgrass ( Spartina pectinata Link). The effect of salt stress on seedling emergence was more pronounced in switchgrass than prairie cordgrass with 31 and 15% reduction, respectively, compared with pure water. In a two-season greenhouse pot experiment, aboveground dry biomass production in control treatments was 8 and 21% higher in prairie cordgrass pc17-102 and pc17-109, respectively, than in EG 1102 switchgrass. Switchgrass EG 1102 produced greater biomass than prairie cordgrass populations when irrigated with moderately saline (5 dS m −1 ) water, although differences were not detected with highly saline water (10 dS m −1 ). Switchgrass EG 2101 emergence, plant growth and cation balance were severely affected by increasing levels of salinity. Overall, several prairie cordgrass populations and lowland switchgrass cultivars were found to have good emergence and high biomass production under moderate to high salt stress and may be good candidates for lignocellulosic feedstocks on salt-affected land. [ABSTRACT FROM AUTHOR]

Highlights: [•] Switchgrass yields were generally not affected by the type of nitrogen fertilizer used. [•] Optimum N rates were variable for different locations, requiring site-specific recommendations. [•] Biomass yields and moisture content were reduced with progressively later harvest timing. [•] Quality of biomass as a bioenergy feedstock was optimized with a winter or spring harvest timing. [Copyright &y& Elsevier]

Abstract: The energy requirement for biomass comminution and the resulting particle physical properties are important factors to study logistic components, select equipment, and assess the overall efficiency of feedstock supply–conversion chain. In this study, mechanical size reduction of Miscanthus (Miscanthus giganteus), switchgrass (Panicum virgatum), willow (Salix babylonica), and energy cane (Saccharum spp.) was carried out using a commercial-scale hammer mill, a bench-scale Retsch SM2000 knife mill and a Retsch SK100 hammer mill. The results showed that the specific energy consumption of biomass comminution and the aperture sizes of the milling screens were related in power-law forms. Biomass moisture significantly influenced comminution energy consumption, especially for finer size reduction. Given a specific milling screen, the Retsch SK100 hammer mill was found more energy efficient than the SM2000 knife mill. This was mainly attributed to the higher motor speed and axial feeding mechanism of the hammer mill. The particle sizes after comminution were found inversely proportional to the bulk densities of all four energy crops used in experiments. In addition, the comminution ratio, being the ratio of the final mean particle size and the original mean particle size, was proportional to energy consumption for all four energy crops. The bulk densities for 4-mm and smaller Miscanthus and switchgrass particles were higher than those of the original bale. Particle size and surface area estimates using commonly used ANSI/ASAE Standards S424.1 and 319.4 were highly sensitive to particle size distributions and shapes. Further studies on standardization of particle size and surface area estimates are needed. [ABSTRACT FROM AUTHOR]