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Paper mill sludge (PMS) is a residual biomass that is generated at paper mills in large quantities. Currently, PMS is commonly disposed in landfills, which causes environmental issues through chemical leaching and greenhouse gas production. In this research, we are exploring the potential of fast pyrolysis process for converting PMS into useful bio-oil and biochar products. We demonstrate that by subjecting PMS to a combination of acid hydrolysis and torrefaction pre-treatment processes it is possible to alter the physicochemical properties and composition of the feedstock material. Fast pyrolysis of pretreated PMS produced bio-oil with significantly higher selectivity to levoglucosenone and significantly reduced the amount of ketone, aldehyde, and organic acid components. Pretreatment of PMS with combined 4% mass fraction phosphoric acid hydrolysis and 220 °C torrefaction processed prior to fast pyrolysis resulted in a 17 times increase of relative selectivity towards levoglucosenone in bio-oil product along with a reduction of acids, ketones, and aldehydes combined from 21 % to 11 %. Biochar, produced in higher yield, has characteristics that potentially make the solid byproduct ideal for soil amendment agent or sorbent material. This work reveals a promising process system to convert PMS waste into useful bio-based products. More in-depth research is required to gather more data information for assessing the economic and sustainability aspects of the process.

Abstract This paper summarizes observations and ideas on cellulose pyrolysis products and structural studies on cellulose chars with a focus on conceptual integration. Information is presented on the larger gas phase oligosaccharides in cellulose pyrolysates, their mechanism of formation and the implications for the processes in the initial stages of char formation. A model for the formation of a new thermally synthesized three-dimensional network polymer is proposed.

Abstract In this research, we evaluated the intent of engaged private forest landowners to supply woody biomass for bioenergy production. The study was conducted in a U.S. state (Kentucky) where private individuals own a majority (78%) of the state's forest resources. Intent of family forest owners was measured using a mail-based survey. We used the Theory of Planned Behavior to model factors that affect landowner intention, and we tested the effect of educational materials on participates' reported intent. Two-thirds of respondents indicated that they intend to include energy wood in future harvests, but the educational material treatment did not affect intentions. Respondents' attitudes, perceived subjective norms, and perceived control each had a significant effect on intent to harvest. No demographic or land ownership characteristics had an effect on behavioral intent. The only prior harvest activity that significantly increased intent was whether the subject had harvested pulpwood from their forest in the past. Respondents identified barriers that may prevent them from harvesting energy wood, providing forestry professionals with a list of challenges to overcome if supply is to be maximized. Lack of bioenergy markets and woodland access issues were the most frequently reported barriers.

Abstract Eucalyptus plantations in the Southern United States offer a viable feedstock for renewable bioenergy. Delivered cost of eucalypt biomass to a bioenergy facility was simulated in order to understand how key variables affect biomass delivered cost. Three production rates (16.8, 22.4 and 28.0 Mg ha −1 y −1 , dry weight basis) in two investment scenarios were compared in terms of financial analysis, to evaluate the effect of productivity and land investment on the financial indicators of the project. Delivered cost of biomass was simulated to range from $55.1 to $66.1 per delivered Mg (with freight distance of 48.3 km from plantation to biorefinery) depending on site productivity (without considering land investment) at 6% IRR. When land investment was included in the analysis, delivered biomass cost increased to range from $65.0 to $79.4 per delivered Mg depending on site productivity at 6% IRR. Conversion into cellulosic ethanol might be promising with biomass delivered cost lower than $66 Mg −1 . These delivered costs and investment analysis show that Eucalyptus plantations are a potential biomass source for bioenergy production for Southern U.S.

Abstract The need to shift from a fossil fuel based economy towards a more bio-based economy has received a lot of attention in public debates and policy making in recent years. However, there seems to be some inconsistency in how a bio-based economy is defined as well as how to estimate the size of this bio-based economy. The current article shows, using a Bibliometric analysis, that the topic "bio-based economy" does not come up extensively in the literature by mid 2010. Moreover, it seems that estimating the importance of the whole of a bio-based economy (and thereby not only focusing on one type of production or product) for a region or country is quite rare, besides a few examples. Within Flanders, one such study has been executed by order of the Flemish government. The current article suggests a framework that can be used to estimate the size of the bio-based economy in other regions or countries. It is based on several steps, so called critical points related to conceptualization, disaggregation, information and valuation. The critical points depend on who has and who wants the information, what the context is, what kind of data is available and whether the research should be comparable. The authors suggest that by following their proposed steps, a reliable estimate of the size of the bio-based economy can be calculated.

Abstract Toosendanin has been suggested as a potential agent for controlling zooplankton contamination in microalgal cultivation. Growth inhibitory and antifeedant influences of toosendanin on the rotifer Brachionus plicatilis were investigated. Sublethal concentrations of toosendanin (1.76–2.59 mg m −3 ) reduced population abundance of rotifers, decreased the lorica length and width, and shrank the body size of survivors notably. No changes were observed in the amictic egg sizes, although the egg production per female rotifer was decreased by toosendanin. Exposure to toosendanin for 4 h significantly decreased the rotifer chlorophyll consumption per individual, indicating the antifeedant effect on rotifers. Analysis on the digestive enzymes showed that exposure to toosendanin had no effect on cellulose activity, but reduced the activities of diastase, pepsase and tryptase in rotifer homogenate. In addition, the half-saturation constant (K m ) of tryptase was increased and the maximum velocity (V max ) of pepsase was decreased by toosendanin, suggesting the direct inhibition of these two proteases by toosendanin in B. plicatilis. This may contribute to the feeding deterrent property of toosendanin on rotifers. The present study heralds the very beginning of studies regarding the toxic mechanism of toosendanin on rotifers, and will accelerate its potential uses for zooplankton extermination in microalgal cultivation.

This discussion highlights and defines key factors and organisational structures for the transformation of local agro-biomass based bioenery systems in Sweden and Denmark. Cross case study analysis is applied to 13 examples where straw is used for energy at various scales within a conceptual framework developed by the authors. This also delivers a cross-country comparison of systems and of the stakeholder entrepreneurs involved in straw-to-energy activities. The paper then delineates four different types of agro-biomass based frameworks for organisation and action. These include ‘small scale local heat production’, ‘medium scale local heat provision with excess for sale’, ‘medium scale conversion and district heating’, and ‘large scale power or combined heat and power generation’. Three categories of farm-based entrepreneurs (i.e. pluriactive, resource exploiting and portfolio farmer) emerge from case studies and are described in the paper. (Less)

Abstract In this paper, we address a corn-stover harvest scheduling problem (CSHSP) that arises when a cellulosic ethanol plant contracts with farmers to harvest corn stover after the grain harvest has been completed. The plant contracts a fleet of harvesting crews, which must be assigned by the plant scheduler to harvest fields as they are called in by the farmers over the harvest season. First, we study the static CSHSP, in which the call in times for the fields are assumed known at the beginning of the season, and propose a mathematical programming-based approach that we show to generate solutions with an average optimality gap of only 6.1% for real-life-inspired instances. We also consider the dynamic CSHSP, in which the call in times are not known at the beginning of the harvest season and the requests arrive randomly over time. The method that we develop for the solution of this problem incurs costs that are about 4.8% higher, on average, than those incurred for the static case. These results exhibit the proposed approach to be robust for use by a plant scheduler in his/her efforts to optimize harvest scheduling as the actual season unfolds. Our proposed approach can also effectively deal with uncertainties encountered in a commercial harvest.