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This paper explores the effects of various parameters on the triticale straw cutting process and the subsequent biomass yield. The impact of blade angle (α), rake angle (β), and the distance between the blade and counter-blade (g) were examined in relation to the shaft torque (T d) on the cutting knife drum, the energy consumption (E c), and the required power (P) for processing straw. Heterogeneity among straw samples was taken into account to ensure accurate calibration of responses. An analysis of variance (ANOVA) was employed to investigate the interactions between input variables and recorded responses, leading to the identification of optimal cutting parameters (α = 35° and β = 0°) that minimise T d , E c , and P. Additionally, the components of the recorded torque T d , including cutting torque (T c) and friction torque (T f), were analysed. Parameter f was used to ascertain the percentage of T f in T d , enabling an optimisation process that confirmed the experimental results and pinpointed the parameter values that resulted in the least energy-intensive process. • ANOVA analysis of influence of process settings on the cutting process results. • The knife blade angle has the most significant influence on energy consumption. • The distance between blade and counter-blade has less influence on energy consumption. • The share of friction torque in the cutting torque facilitated numerical optimisation. • Lower energy consumption of cutting improves energy balance of biofuel production. [ABSTRACT FROM AUTHOR]

Combined heat and power (CHP) plants fueled by biomass can collect and utilize waste straw resources in a productive way. This paper considers the impact of regional factors on biomass energy potential and the energy needs of the population, so as to study the differences in construction of biomass CHP plants and the collection scope of raw materials, and proposes evaluating suitability for biomass energy development based on scope of resource collection. Taking five counties in China as its study areas, this paper assesses biomass energy potential. A topology system of biomass CHP plants has been reasonably established in different counties through ArcGIS, the required installed capacity has been calculated according to the number of persons served by such plants. Finally, the collection length and corresponding value range of raw materials of CHP plants along roads has been obtained based on biomass energy potential and energy demand. The result shows that the differences in area, straw yield and biomass fuelization rate depending on regions have a great impact on biomass energy potential, while the residue-to-product ratio of straw and biomass calorific value have less of an impact. When the biomass energy per capita of a region reaches 9.75GJ/person, it is suitable for biomass energy development. The installed capacity in the biomass CHP plant system of each study area is mostly within the scope of 3–59 MW, and the collection length of corresponding biomass resources of such plants along roads is mostly within the scope of 5.09–25.23 km. • Assessment of biomass energy potential based on regional biomass differences. • Suitability for biomass energy development based on scope of resource collection. • Strategies for biomass plant system construction in different regions are proposed. [ABSTRACT FROM AUTHOR]

In the global effort to reduce CO 2 emissions, the concurrent enhancement of pollutant degradation and reductions in fossil fuel consumption are pivotal aspects of microalgae-mediated wastewater treatment. Clarifying the degradation mechanisms of bacteria and microalgae during pollutant treatment, as well as regulatory biolipid production, could enhance process sustainability. The synergistic and inhibitory relationships between microalgae and bacteria are introduced in this paper. The different stimulators that can regulate microalgal biolipid accumulation are also reviewed. Wastewater treatment technologies that utilize microalgae and bacteria in laboratories and open ponds are described to outline their application in treating heavy metal-containing wastewater, animal husbandry wastewater, pharmaceutical wastewater, and textile dye wastewater. Finally, the major requirements to scale up the cascade utilization of biomass and energy recovery are summarized to improve the development of biological wastewater treatment. [Display omitted] • The synergistic and antagonistic interactions between bacteria and microalgae are summarized. • Different stimulators that could regulate microalgal biolipid accumulation are also reviewed. • Wastewater treatment technologies that utilize microalgae and bacteria in the laboratory and open ponds are described. • The trends in microalgae-bacterial consortium in multistage energy production are proposed. [ABSTRACT FROM AUTHOR]

Flux balance analysis (FBA) and associated techniques operating on stoichiometric genome-scale metabolic models play a central role in quantifying metabolic flows and constraining feasible phenotypes. At the heart of these methods lie two important assumptions: (i) the biomass precursors and energy requirements neither change in response to growth conditions nor environmental/genetic perturbations, and (ii) metabolite production and consumption rates are equal at all times (i.e., steady-state). Despite the stringency of these two assumptions, FBA has been shown to be surprisingly robust at predicting cellular phenotypes. In this paper, we formally assess the impact of these two assumptions on FBA results by quantifying how uncertainty in biomass reaction coefficients, and departures from steady-state due to temporal fluctuations could propagate to FBA results. In the first case, conditional sampling of parameter space is required to re-weigh the biomass reaction so as the molecular weight remains equal to 1 g mmol−1, and in the second case, metabolite (and elemental) pool conservation must be imposed under temporally varying conditions. Results confirm the importance of enforcing the aforementioned constraints and explain the robustness of FBA biomass yield predictions. • The propagation of biomass coefficient uncertainty and metabolite imbalances is systematically assessed in FBA. • The importance of sampling biomass coefficients so as the biomass molecular weight is always scaled to one is highlighted. • Conservation of metabolite pools and elemental balances is demonstrated to be necessary in modeling steady-state departure. • FBA-predicted biomass yield, but not metabolic fluxes, was found to be insensitive to noise in biomass coefficients. • Departures from metabolite steady-state almost always led to a drastic reduction in biomass yield. [ABSTRACT FROM AUTHOR]

Abstract A transition towards a bio-based economy is accompanied by a growing demand for biomass resources as fossil fuels need to be replaced for the more sustainable production of consumer goods, chemicals and energy. To increase the supply of renewable biomass and avoid a conflict with food production, currently underutilized by-products (i.e. leaves, stems) from horticultural production could be valorised as feedstock. The success of this approach depends on farmers' willingness to adopt novel practices like the collection and treatment of plant leaves. However, literature on factors influencing farmers' decisions to adopt novel practices aimed to foster the Bioeconomy is limited. This paper addresses this gap by exploring drivers of farmers' interest in the valorisation of by-products. To this aim, the Value-Belief-Norm theory was used and expanded by contextual factors, such as the perceived market demand for biomass and future environmental policies. A survey with German fruit and vegetable farmers (N = 96) has been carried out and data have been analysed with a Structural Equation Model. Findings suggest that the Value-Belief-Norm theory is a relevant framework for the agricultural domain to predict farmers' interest in the valorisation of horticultural by-products. Results further indicate that an internal ecological worldview is potentially relevant for farmers' perception of contextual conditions aimed to foster the Bioeconomy. These outcomes could have managerial and policy implications associated with the identification of potential lead users to trigger the diffusion of innovative sustainable practices and generally foster the Bioeconomy. Highlights • The paper explores internal and contextual drivers for farmers' interest in practices aimed to foster the Bioeconomy. • The valorisation of horticultural by-products has been used as a case study. • Survey data have been analysed with a Structural Equation Model. • The value-belief-norm theory is relevant to predict farmers' interest in the valorisation of horticultural by-products. • Farmers' ecological worldview potentially affects their perception of contextual conditions aimed to foster the Bioeconomy. [ABSTRACT FROM AUTHOR]

The porous carbon with angstrom-sized pores is important in supercapacitor applications, because of its high pack density and high specific capacitance. In this paper, a facile method is proposed for the preparation of hierarchical porous carbon with high-volume angstrom-sized pores. Onion, as the typical biomass in this research, is used as carbon precursor. First, onion was etched by KOH to obtain a water-soluble lignin-potassium-salt/cellulose composite. This composite was further pyrolyzed under N 2 atmosphere to obtain onion derived porous carbon (OPC). The morphology and porous structure of OPC were characterized by scanning electron microscope and N 2 adsorption/desorption. The supercapacitive performances of OPC were investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge-discharge. OPC shows high specific surface area with high-volume angstrom-sized pores in carbon matrix. When used as supercapacitor electrode materials, OPC shows high specific capacitance and good cycling stability. This paper opens a general way to prepare porous carbon from biomasses, which will promote the development of biomass utilization, preparation of porous carbon and supercapacitors. [ABSTRACT FROM AUTHOR]

With the gradual growth of greenhouse gas (GHG) emissions during the agricultural cultivation cycle, GHG emissions specific to the production and conversion of biomass energy is becoming increasingly problematic. Current studies lack analysis of net GHG emissions generated during full life cycle of agricultural cultivation, straw use and bioenergy production. This study measures the global warming potential of biomass energy production and conversion processes under different agricultural cultivation cycle systems based on life cycle approach, accompanied by four straw treatment methods: fast pyrolysis, slow pyrolysis, flash pyrolysis and anaerobic fermentation. The demonstration of Heilongjiang Province showed that the net GHG emissions of rice and soybean over 52.39% and 101.57% higher than those of corn, respectively. The amount of standard coal saved by fast pyrolysis treatment, slow pyrolysis treatment and anaerobic fermentation treatment of straw was only 38.38%, 78.02% and 61.98% of that of flash pyrolysis treatment. The relationship between environmental pressure and economic growth was decoupled during 2011–2017 and coupled in 2017–2020. This study contributes to green production of biomass energy. The methodology in this paper can be used to account for and assess the carbon effect of the entire straw recycling chain in any region. • GHG emissions of biomass production are accounted based on agricultural residues. • Carbon accounting models for different links, crops and regions are developed. • Four straw treatment methods in different circular agriculture modes are proposed. • Trade-offs between resources, economy and environment are resolved. [ABSTRACT FROM AUTHOR]

Abstract: Endo-xylanases play a key role in the depolymerization of xylan and recently, they have attracted much attention owing to their potential applications on biofuels and paper industries. In this work, we have investigated the molecular basis for the action mode of xylanases 10B at high temperatures using biochemical, biophysical and crystallographic methods. The crystal structure of xylanase 10B from hyperthermophilic bacterium Thermotoga petrophila RKU-1 (TpXyl10B) has been solved in the native state and in complex with xylobiose. The complex crystal structure showed a classical binding mode shared among other xylanases, which encompasses the −1 and −2 subsites. Interestingly, TpXyl10B displayed a temperature-dependent action mode producing xylobiose and xylotriose at 20°C, and exclusively xylobiose at 90°C as assessed by capillary zone electrophoresis. Moreover, circular dichroism spectroscopy suggested a coupling effect of temperature-induced structural changes with this particular enzymatic behavior. Molecular dynamics simulations supported the CD analysis suggesting that an open conformational state adopted by the catalytic loop (Trp297-Lys326) provokes significant modifications in the product release area (+1,+2 and +3 subsites), which drives the enzymatic activity to the specific release of xylobiose at high temperatures. [ABSTRACT FROM AUTHOR]

Cloud computing offers attractive features for both service providers and customers. Users benefit from the pay-as-you-go model by saving expenditures and service providers are deploying their services to cloud data centers to reduce their maintenance efforts. However, due to the fast growth of cloud data centers, the energy consumed by the data centers can lead to a huge amount of carbon emission with environmental impacts, and the carbon intensity of different locations are varied among different power plants according to the sources of energy. Thus, in this paper, to address the carbon emission problem of data centers, we consider shifting the workloads among multi-cloud located in different time zones. We also formulate the energy usage and carbon emission of data centers and model the solar power corresponding to the locations. This helps to reduce the usage of brown energy and maximize the utilization of renewable energy at different locations. We propose an approach for managing carbon footprint and renewable energy for multiple data centers at California, Virginia, and Dublin, which are in different time zones. The results show that our proposed approaches that apply workload shifting can reduce around 40% carbon emission in comparison to the baseline while ensuring the average response time of user requests. • Model considering power consumption, renewable energy and carbon footprint. • Algorithm for managing the renewable energy and carbon footprint for data centers. • Evaluations on the impacts of requests executed in different time zones. [ABSTRACT FROM AUTHOR]

Abstract Remediation of polluted soils using phytoremediation techniques is an effective strategy. However, the use of the biomass from these soils for energy purposes may raise efficiency and pollution emission problems and there is currently little research on this issue. In this work, the main results of a fluidized-bed gasification treatment conducted on poplar biomass pruning residues from a multi-contaminated area are presented. The samples were collected from an experimental site in which a plant-assisted bioremediation (PABR) technology has been applied since 2013 to reduce the soil heavy metal (HM) and polychlorinated biphenyl (PCB) contents. The main goal of this study was to identify the specific treatment necessary, in addition to conventional tar reforming, for trapping possible residues of HMs and PCBs in ashes during the gasification process. In our study, we demonstrate that gasification of contaminated biomass coming from PABR (where contaminant residues are concentrated mainly in the roots and are insignificant in the shoots) produces syngas whose characteristics are similar to those obtained using non-contaminated biomass. The results showed that contaminant concentrations in the prunings were negligible; the total amount of PCBs was 1.63 ng/g, while HMs ranged from 0.01 to 0.70 mg/kg, except for Cu and Zn (∼20 mg/kg). Furthermore, the presence in the biomass of Ca and traces of other metals showed a possible catalytic effect with an improvement in the tar conversion in the gasifier leading to a reduction of 5–10% in tar content. The overall results suggest that a specific treatment for pollutant capture is necessary only when the roots, the part of the plants where these contaminants are concentrated, are sampled and used for the gasification process. Although energy from biomass produced on a contaminated site is currently considered waste and involves disposal costs, this paper shows that the poplar biomass grown on a multi-contaminated soil can be used for energy purposes without any impact on the environment. Graphical abstract Image 1 Highlights • Biomass quality assessment is necessary for evaluating gasification capabilities. • Poplar from PABR accumulate contaminants mainly in the roots. • Trace PCB concentrations in biomass not affect the gasification treatment. • The soil characteristics affect the yield and quality of syngas. • Ca occurrence in soil and biomass has a catalytic effect in tar cracking increase. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the diet and trophic structure of fish assemblages caught in two zones of the largest (∼220 km2) hypersaline coastal lagoon in South America were addressed quarterly along 2011, and the patterns were compared among seasons and to a previous study performed during typical hypersaline conditions (i.e. 1993) to assess the short- and long-term effects of desalinisation. Our results confirmed that in 2011, Araruama Lagoon experienced a strong decrease in salinity, particularly in the autumn, with the ranging values (i.e. 37–48) remaining below to the salinities (i.e. 52–67) reported for most of the 1965–2005 period, but matching those (i.e. ≤ 41 on the average) recorded during the atypical less-hypersaline conditions of 1989–1990. Fish trophic structure recorded during 2011 was composed of five guilds, in decreasing order of biomass: planktivores (31.14%), detritivores (26.24%), invertivores (25.65%), piscivores (15.09%), and omnivores (1.58%). This structure resembled more those of similar, but comparatively less hypersaline systems in Africa and Australia, than that of extreme hypersaline lagoons in Mexico or Araruama lagoon in a typically hypersaline year. Our findings indicate that increased contributions of planktivores and detritivores could be used as promising predictors of, respectively, salination and desalinisation processes and thus shifts in the ecosystem trophic state. Variations on the biomasses of piscivores and invertivores were apparently more related to short-term salinity changes among seasons and across the lagoon zones. Since the relationships between fish trophic structure and desalinisation and its associated effects were complex, long-term studies using complementary and integrative approaches, such as stable isotopes and functional traits, are recommended to confirm our findings for Araruama Lagoon and validate our hypothesis for other similar hypersaline ecosystems. [ABSTRACT FROM AUTHOR]

Low-carbon transition in the non-electric energy sector, which includes transport and heating energy, is necessary for achieving the 2 °C target. Meanwhile, as non-electric energy accounts for over 60% of total water consumption in the energy supply sector, it is vital to understand future water trends in the context of decarbonization. However, few studies have focused on life-cycle water impacts for non-electric energy; besides, applying conventional LCA methodology to assess non-electric energy has limitations. In this paper, a Multi-Regional Hybrid Life-Cycle Assessment (MRHLCA) model is built to assess total CO 2 emissions and water consumption of 6 non-electric energy technologies – transport energy from biofuel and gasoline, heat supply from natural gas, biogas, coal, and residual biomass, within 7 major emitting economies. We find that a shift to natural gas and residual biomass heating can help economies reduce 14–65% CO 2 and save more than 21% water. However, developed and developing economies should take differentiated technical strategies. Then we apply scenarios from IMAGE model to demonstrate that if economies take cost-effective 2 °C pathways, the water conservation synergy for the whole energy supply sector, including electricity, can also be achieved. [ABSTRACT FROM AUTHOR]

Biofuels have received a lot of attention as an important source of renewable energy, with number of economic impacts. This study aims to investigate the economic potential of biofuels and then extract core aspects of how biofuels relate to a sustainable economy in order to achieve a sustainable biofuel economy. This study conducts a bibliometric analysis of publications about biofuel economic research covering 2001 to 2022 experimenting with multiple bibliometric tools, such as R Studio, Biblioshiny, and VOSviewer. Findings show that research on biofuels and biofuel production growth are positively correlated. From the analyzed publications, The United States, India, China, and Europe are the largest biofuel markets, with the USA taking the lead in publishing scientific papers, engaging country collaboration on biofuel, and has the highest social impact. Findings also show that the United Kingdom, the Netherlands, Germany, France, Sweden, and Spain are more inclined to develop sustainable biofuel economies and energy than other European countries. It also indicates that sustainable biofuel economies are still far behind those of less developed and developing countries. Besides, this study finds that biofuel linked to sustainable economy with poverty reduction, agriculture development, renewable energy production, economic growth, climate change policy, environmental protection, carbon emission reduction, green-house gas emission, land use policy, technological innovations, and development. The findings of this bibliometric research are presented using different clusters, mapping, and statistics. The discussion of this study affirms the good and effective policies for a sustainable biofuel economy. • The USA, China, and Europe are highly interested in biofuel economy research. • Less developed and developing countries lag far behind sustainable biofuel economies. • Key issue for sustainable biofuel economy is better policies for better society. • High CO2 emitting countries are more aware of biofuel research & collaboration. • Advanced biofuels production technologies are required to boost biofuel economy. [ABSTRACT FROM AUTHOR]

Plant biomass degradation by fungi has implications for several fields of science. The enzyme systems employed by fungi for this are broadly used in various industrial sectors such as food & feed, pulp & paper, detergents, textile, wine, and more recently biofuels and biochemicals. In addition, the topic is highly relevant in the field of plant pathogenic fungi as they degrade plant biomass to either gain access to the plant or as carbon source, resulting in significant crop losses. Finally, fungi are the main degraders of plant biomass in nature and as such have an essential role in the global carbon cycle and ecology in general. In this review we provide a global view on the development of this research topic in saprobic ascomycetes and basidiomycetes and in plant pathogenic fungi and link this to the other papers of this special issue on plant biomass degradation by fungi. [ABSTRACT FROM AUTHOR]

The implementation of different pretreatment techniques and technologies prior to effluent discharge is a direct result of the inefficiency of several existing wastewater treatment methods. A majority of the industrial sectors have known to cause severe negative effects on the environment. The five major polluting industries are the paper and pulp mills, coal manufacturing facilities, petrochemical, textile and the pharmaceutical sectors. Pretreatment methods have been widely used in order to lower the toxicity levels of effluents and comply with environmental standards. In this review, the possible environmental benefits and concerns of adopting different pretreatment technologies for renewable energy production and product/resource recovery has been reviewed and discussed. [ABSTRACT FROM AUTHOR]

This paper concerns the process of production and properties of pellets based on biomass wastes. Co-pelletization was performed for sewage sludge from municipal wastewater treatment plant and other biomass material such as animal and olive wastes. The aim of the present study was to identify the key factors affecting on the sewage sludge and agricultural residues co-pelletization processes conditions. The impact of raw material type, pellet length, moisture content and particle size on the physical properties was investigated. The technic and technological aspects of co-pelletization were discussed in detail. The physical parameters of pellets, i.e.: drop strength, absorbability and water resistance were determined. Among others, also energy parameters: low and high heat value, content of ash and volatiles were presented. Results showed the range of raw materials moisture, which is necessary to obtain good quality biofuels and also ratio of sewage sludge in pelletizing materials. The analysis of the energetic properties has indicated that the pellet generated on the basis of the sewage sludge and another biomass materials can be applied in the processes of co-combustion with coal. Those biofuels are characterised with properties making them suitable for use in thermal processes and enabling their transport and storage. [ABSTRACT FROM AUTHOR]

This paper provides a perspective for comparing trade-offs between harvested wood flows and forest carbon stocks with different forest management regimes. A constant management regime applied to a forest area with an even age-class distribution leads to a steady state, in which the annual harvest and carbon stocks remain constant over time. As both are desirable – carbon stocks for mitigating climate change and harvests for the economic use of wood and displacing fossil fuels – an ideal strategy should be chosen from a set of management regimes that are Pareto-optimal in the sense of multi-criteria decision-making. When choosing between Pareto-optimal alternatives, the trade-off between carbon stock and harvests is unavoidable. This trade-off can be described e.g. in terms of carbon payback times or carbon returns. As numerical examples, we present steady-state harvest levels and carbon stocks in a Finnish boreal forest region for different rotation periods, thinning intensities and collection patterns for harvest residues. In the set of simulated management practices, harvest residue collection presents the most favorable trade-off with payback times around 30–40 years; while Pareto-optimal changes in rotation or thinnings exhibited payback times over 100 years, or alternatively carbon returns below 1%. By extending the rotation period and using less-intensive thinnings compared to current practices, the steady-state carbon stocks could be increased by half while maintaining current harvest levels. Additional cases with longer rotation periods should be also considered, but were here excluded due to the lack of reliable data on older forest stands. [ABSTRACT FROM AUTHOR]

In order to reduce the harmful effect on the environment, European Union allowed using the biofuel blends as fuel for the internal combustion engines. Experimental studies have been carried on, dealing with the biodiesel influence on the emission concentrations, showing inconclusive results. In this paper numerical model for pollutant prediction in internal combustion engines is presented. It describes the processes leading towards the pollutant emissions, such as spray particles model, fuel disintegration and evaporation model, combustion and the chemical model for pollutant formation. Presented numerical model, implemented in proprietary software FIRE ® , is able to capture chemical phenomena and to predict pollutant emission concentration trends. Using the presented model, numerical simulations of the diesel fuelled internal combustion engine have been performed, with the results validated against the experimental data. Additionally, biodiesel has been used as fuel and the levels of pollutant emissions have been compared to the diesel case. Results have shown that the biodiesel blends release lower nitrogen oxide emissions than the engines powered with the regular diesel. [ABSTRACT FROM AUTHOR]

In recent years, issues relating to fat, oil and grease (FOG) in sewer systems have intensified. In the media, sewer blockages caused by FOG waste deposits, commonly referred to as ‘fatbergs’, are becoming a reminder of the problems that FOG waste can cause when left untreated. These FOG blockages lead to sanitary sewer overflows, property flooding and contamination of water bodies with sewage. Despite these financial and environmentally detrimental effects, a homogenous FOG waste management method has not been developed internationally. However, some successful enduring FOG management programmes have been established, such as in Dublin city and in Scandinavian countries. The aim of this paper is to carry out a review on existing FOG research and management approaches. FOG management involves comprehending: (1) FOG deposition factors in the sewer, (2) FOG prevention and awareness tactics undertaken internationally and (3) potential utilisation methods for FOG waste. This review will highlight that preventing FOG from entering the sewer is the most common approach, often through simple awareness campaigns. The diverted FOG is rarely valorised to bioenergy or biomaterials, despite its potential. Thus, all facets of the FOG waste lifecycle must be identified and managed. Advancements in processes and techniques must be assessed to best determine the future evolution of FOG waste management to assist in achieving a sustainable urban environment. [ABSTRACT FROM AUTHOR]

Abstract: Protein is a large component of the standing biomass of algae. The total protein content of algae is difficult to measure because of the problems encountered in extracting all of the protein from the cells. Here we modified an existing protein assay to measure total protein in microalgae cells that involves little or no extraction of protein from the cells. Aliquots of fresh or pretreated cells were spotted onto filter paper strips. After drying, the strips were stained in a 0.1% (w/v) solution of the protein stain Coomassie Brilliant Blue R-250 for 16 to 24h and then destained. The stained protein spots were cut out from the paper, and dye was eluted in 1% (w/v) sodium dodecyl sulfate (SDS). Absorbance at 600nm was directly proportional to protein concentration. Cells that were recalcitrant to taking up the dye could be either heated at 80°C for 10min in 1% SDS or briefly sonicated for 3min to facilitate penetration of the dye into the cells. Total protein measured in Chlorella vulgaris using this method compared closely with that measured using the total N method. Total protein concentrations were measured successfully in 12 algal species using this dye binding method. [Copyright &y& Elsevier]

Abstract: Aqueous-phase hydrodeoxygenation of sugar and sugar-derived molecules can be used to produce a range of alkanes and oxygenates. In this paper, we have identified the reaction intermediates and reaction chemistry for the aqueous-phase hydrodeoxygenation of sorbitol over a bifunctional catalyst (Pt/SiO2–Al2O3) that contains both metal (Pt) and acid (SiO2–Al2O3) sites. A wide variety of reactions occur in this process including Ceavage, Ceavage, and hydrogenation reactions. The key Ceavage reactions include: retro-aldol condensation and decarbonylation, which both occur on metal catalytic sites. Dehydration is the key Ceavage reaction and occurs on acid catalytic sites. Sorbitol initially undergoes dehydration and ring closure to produce cyclic C6 molecules or retro-aldol condensation reactions to produce primarily C3 polyols. Isosorbide is the major final product from sorbitol dehydration. Isosorbide then undergoes ring opening hydrogenation reactions and a dehydration/hydrogenation step to form 1,2,6-hexanetriol. The hexanetriol is then converted into hexanol and hexane by dehydration/hydrogenation. Smaller oxygenates are produced by Ceavage. These smaller oxygenates undergo dehydration/hydrogenation reactions to produce alkanes from C1–C5. The results from this paper suggest that hydrodeoxygenation chemistry can be tuned to make a wide variety of products from biomass-derived oxygenates. [Copyright &y& Elsevier]

The collection radius of biomass raw materials is an important factor affecting the volume of raw materials for energy utilization. At present, it is usually studied based on a single biomass combined heat and power (CHP) plant. However, as the heat transfer threshold of biomass CHP plant is limited, it is necessary to consider the optimal collection radius and biomass raw material allocation under the distribution mode of multiple power plants to improve the overall utilization rate of raw materials. Biomass raw material collection distance threshold (BCDT) refers to the maximum road length between the resource point (that allows the transportation of raw materials to the biomass CHP plant) and the biomass CHP plant. Under the mode of multi-power plant planning, the greater the BCDT is, the more destinations there will be for raw materials to be transported to from the same resource point, and the more flexible the transportation plans and allocation of transportation volumes will be. This also means more raw materials can be ultimately used for energy utilization, which leads to higher transportation cost. Therefore, determining the appropriate BCDT plays a key role in the unified planning of biomass raw materials. Based on the limitation of heat transfer threshold, this paper carries out multi-power plant planning with Fuxin City as the research object. Based on such planning, ArcGIS is used to generate biomass raw material planning schemes with different BCDTs. Then the transportation cost and energy surplus factor (ratio of renewable resource potential to energy demand) of each scheme are calculated and compared. The results show that there is a positive correlation between BCDT and the energy surplus factor. With the increase of BCDT, the growth rate of the energy surplus factor gradually becomes slower. The study also allows to set the utilization threshold of biomass energy utilization capacity and obtain the corresponding BCDT. In order to achieve a higher energy surplus factor, it is recommended that 40 km be used as the BCDT when carrying out uniform planning for biomass raw materials. At this time, the utilization of biomass energy utilization capacity is 75%, which can achieve a high degree of energy self-sufficiency and ensure its economic competitiveness. • The mode of multi-power plant planning is considered. • Collection distance instead of collection radium is used. • The method of unified allocation of biomass resources is confirmed. • The optimal biomass raw material collection distance threshold is determined. [ABSTRACT FROM AUTHOR]

This paper reports on a seasonal pattern comparison of microbial enzymatic activities and biomass responses based on a conventional biofilter (BF, without earthworm) and a vermifilter (VF, with earthworm, Eisenia fetida ) for excess sludge treatment. The volatile suspended solids (VSS) reduction, viable cell number and enzyme activities were assayed to probe what made the VF operate stably. The results indicated that the earthworm activities can polish the VSS reduction with 27.17% more than the BF. Though the VF had a lower level in the viable cell number compared with the BF, the earthworm strongly improved the microbial enzymatic activities such as INT-dehydrogenase, protease, β-glucosidase and amylase, which can explain the excellent performance of VSS reduction. The correlation analysis documented that the VSS reduction was positively correlated with microbial enzyme activities. More importantly, the earthworm enabled the VF to avoid the detrimental influence of temperature, which guaranteed a stable performance during seasonal variations. [ABSTRACT FROM AUTHOR]

Ethanol and biodiesel industries generate large volumes of by-products, such as vinasse and glycerol, which are suitable for biogas exploitation. This paper assessed the applicability and process performance of the anaerobic structured-bed reactor (AnSTBR) for the mesophilic (30 °C) continuous (105 days) anaerobic co-digestion of sugarcane vinasse and distilled glycerol under increasing organic loading rates (OLR) (0.5–5.0 kgCOD m−3d−1). The highest methane yield (211 NmL g−1COD rem.) and volumetric production (668 NmL L−1d−1) occurred at an OLR of 3.5 kgCOD m−3d−1. The performance of the AnSTBR showed high removal efficiencies of total COD (77.1%), carbohydrates (81.9%), and glycerol content (99.7%). Biofilm growth enhancement within the reactor offset the impairment of methanogenesis activity at high organic loads. The prompt biodegradability of glycerol reinforced the importance of gradually increase the organic load to prevent the buildup of volatile acids and maintain a stable long-term co-digestion system. [Display omitted] • Anaerobic co-digestion of sugarcane vinasse and distilled glycerol was assessed. • Biomass retention patterns in the co-digestion system were investigated. • The high biodegradability of glycerol required a gradual increase in organic load. • High organic matter removal (∼80%) was reached regardless of methanogenesis. • Enhanced biofilm growth offset impaired methanogenesis at high organic loads. [ABSTRACT FROM AUTHOR]

Due to the growing concerns on the climate change and sustainability on petrochemical resources, DOE selected and announced the bio-based top 12 building blocks and discussed the needs for developing biorefinery technologies to replace the current petroleum based industry in 2004. Over the last 10 years after its announcement, many studies have been performed for the development of efficient technologies for the bio-based production of these chemicals and derivatives. Now, ten chemicals among these top 12 chemicals, excluding the l -aspartic acid and 3-hydroxybutyrolactone, have already been commercialized or are close to commercialization. In this paper, we review the current status of biorefinery development for the production of these platform chemicals and their derivatives. In addition, current technological advances on industrial strain development for the production of platform chemicals using micro-organisms will be covered in detail with case studies on succinic acid and 3-hydroxypropionic acid as examples. [ABSTRACT FROM AUTHOR]

Pruning is a cultural operation linked to Mediterranean agricultural management and it offers through its wastes the chance to procure biofuels. Currently, these residues are disposed of by burning or shredding, not being exploited because of several technical difficulties in extraction, handling and transport as well as because of the lack of accurate data on the quantity and suitability of these residues. However, recent work has reported methods of supplying new biomass detection models and concentration locations. These make it possible to tackle reliable collection plans as a part of the decision support system in a biomass supply management information system. This paper addresses the biomass collection problem, as an application of the classical vehicle routing problem, where minimum cost routes have to be calculated for a fleet of several agricultural vehicles (chippers, trucks, tipper trailers and tractors). A hybrid approach based on genetic algorithms and local search methods is presented to solve a real case study. Results show a significant improvement in the operational efficiency obtained by applying such methods that come from the industrial engineering domain. [ABSTRACT FROM AUTHOR]

Abstract: This paper develops an integrated model of the fuel and agricultural sectors to analyze the welfare and greenhouse gas emission (GHG) effects of the existing Renewable Fuel Standard (RFS), a Low Carbon Fuel Standard (LCFS) and a carbon price policy. The conceptual framework shows that these policies differ in the incentives they create for the consumption and mix of different types of biofuels and in their effects on food and fuel prices and GHG emissions. We also simulate the welfare and GHG effects of these three policies which are normalized to achieve the same level of US GHG emissions. By promoting greater production of food-crop based biofuels, the RFS is found to lead to a larger reduction in fossil fuel use but also a larger increase in food prices and a smaller reduction in global GHG emissions compared to the LCFS and carbon tax. All three policies increase US social welfare compared to a no-biofuel baseline scenario due to improved terms-of-trade, even when environmental benefits are excluded; global social welfare increases with a carbon tax but decreases with the RFS and LCFS due to the efficiency costs imposed by these policies, even after including the benefits of mitigating GHG emissions. [Copyright &y& Elsevier]

Abstract: This paper develops an analytical framework for comparing the welfare effects of energy efficiency standards and pricing policies for reducing gasoline, electricity, and nationwide carbon emissions. The model is parameterized with US data and includes key externalities in the energy/transportation sectors and possible underinvestment in energy efficiency due to “misperceptions” over energy savings. Even with large misperceptions, the extra welfare gains from complementing efficient pricing policies with energy efficiency standards are zero for reducing gasoline and 5 percent for reducing electricity. And when viewed as substitutes, these standards forgo 60 percent or more of the potential welfare gains from corresponding pricing policies. A combination of energy efficiency and emissions standards is more than three times as costly as carbon pricing when there is no misperception over energy savings, and even with large misperceptions, combining carbon pricing with gasoline/electricity taxes is better than combining it with energy efficiency standards. [Copyright &y& Elsevier]

Abstract: A carbon tax on fuel would penalize carbon intensive fuels like gasoline and shift fuel consumption to less carbon intensive alternatives like biofuels. Since biofuel production competes for land with agricultural production, a carbon tax could increase land rents and raise food prices. This paper analyzes the welfare effect of a carbon tax on fuel consisting of gasoline and biofuel in the presence of a labor tax, with and without a biofuel subsidy. The market impacts of a carbon tax are also compared with that of a subsidy. Findings show that if a carbon tax increases biofuel demand, the tax interaction effect due to higher fuel prices is exacerbated by higher land rent and food prices and greater erosion of the carbon tax base. Thus, the second best optimal carbon tax for fuel is lower with biofuel in the fuel mix, especially if biofuel is subsidized. [Copyright &y& Elsevier]

Abstract: Analyses of global warming impacts from forest bioenergy systems are usually conducted either at a single stand level or at a landscape level, yielding findings that are sometimes interpreted as contrasting. In this paper, we investigate and reconcile the scales at which environmental impact analyses of forest bioenergy systems are undertaken. Focusing on the changes caused in atmospheric CO2 concentration of forest bioenergy systems characterized by different initial states of the forest, we show the features of the analyses at different scales and depict the connections between them. Impacts on atmospheric CO2 concentration at a single stand level are computed through impulse response functions (IRF). Results at a landscape level are elaborated through direct application of IRFs to the emission profile, so to account for the fluxes from all the stands across time and space. Impacts from fossil CO2 emissions are used as a benchmark. At a landscape level, forest bioenergy causes an increase in atmospheric CO2 concentration for the first decades that is similar to the impact from fossil CO2, but then the dynamics clearly diverge because while the impact from fossil CO2 continues to rise that from bioenergy stabilizes at a certain level. These results perfectly align with those obtained at a single stand for which characterization factors have been developed. In the hypothetical case of a sudden cessation of emissions, the change caused in atmospheric CO2 concentration from biogenic CO2 emissions reverses within a couple of decades, while that caused by fossil CO2 emissions remains considerably higher for centuries. When counterfactual aspects like the additional sequestration that would have occurred in the forest if not harvested and the theoretical displacement of fossil CO2 are included in the analysis, results can widely differ, as the CO2 debt at a landscape level ranges from a few years to several centuries (depending on the underlying assumptions considered). [Copyright &y& Elsevier]

Biomass-fuelled Combined Heat and Power Generation (CHP) systems can efficiently convert chemical energy contained in biomass into electricity and heat. Currently there is a large number of abandoned forests and biomass of agroforestry origin that is not being used. The use of residual biomass as a source of energy in CHP systems is presented as a particularly attractive alternative for energy obtention. This paper presents the results of a biomass boiler coupled to an Organic Rankine Cycle (ORC). Three residual biomasses, named pruning vine, pruning kiwi and gorse have been selected due to their potentiality and availability in the Galicia-North Portugal Euroregion. For this purpose, micro-cogeneration tests at bench scale were performed, based fundamentally on varying dissipation conditions in the low-grade temperature range (below 100 °C). Micro-cogeneration performance was assessed based on the electrical power and efficiency obtained, along with the global efficiency achieved (electrical plus thermal). Combustion measurements comprised gaseous emissions analyses and determination of the efficiency of the process. Micro-cogeneration results obtained show that differences in temperature between the hot and the cold source have a significant influence. The higher the temperature difference, the higher the electrical power and efficiency, as well as the higher global performance obtained, with values close to the maximum of the ORC employed (i.e 4 kW e , 9% and 96% respectively). Thus, the technical feasibility of the system to simultaneously obtain heat and electricity from low grade heat sources in small-scale applications was demonstrated. Regarding to combustion, parameters regulated by European emission standards are under the limits using the biofuels (residual biomasses) studied. Thereby, the suitability of those biomasses in thermochemical valorization processes was demostrated. • CHP systems can efficiently convert biomass energy into electricity and heat. • ORC used only attends to the temperature difference between sources. • Electrical power obtained is close to the maximum of the equipment (4kW e). • Residual biomass microcogeneration tests performed showed cogeneration yields of 96%. • Micro-cogeneration emerges as ideal for energy recovery from residual biomass. [ABSTRACT FROM AUTHOR]

Ever-growing demands for energy, the unsustainability of fossil fuel due to its scarcity and massive impact on global economies and the environment, have encouraged the research on alternative power sources to work upon for the governments, companies, and scientists across the world. Enzymatic biofuel cells (eBFCs) is one category of fuel cell that can harvest energy from biological moieties and has the future to be used as an alternative source of energy. The aim of this review is to summarize the background and state-of-the-art in the field of eBFCs. This review article will be very beneficial for a wide audience including students and new researchers in the field. A part of the paper summarized the challenges in the preparation of anode and cathode and the involvement of nanomaterials and conducting polymers to construct the effective bioelectrodes. It will provide an insight for the researchers working in this challenging field. Furthermore, various applications of eBFCs in implantable power devices, tiny electronic gadgets, and self powered biosensors are reported. This review article explains the development in the area of eBFCs for several years from its origin to growth systematically. It reveals the strategies that have been taken for the improvements required for the better electrochemical performance and operational stability of eBFCs. It also mentions the challenges in this field that will require proper attention so that the eBFCs can be utilized commercially in the future. The review article is written and structurized in a way so that it can provide a decent background of eBFCs to its reader. It will definitely help in enhancing the interest of reader in eBFCs. [Display omitted] • A general introduction along with the background and advances in the field of eBFCs are explained. • The challenges in the preparation of anode and cathode for the employment in eBFCs are mentioned. • Enzyme immobilization and stabilization at surface of electrode via Physical adsorption, Covalent binding, Entrapment, and Cross-linking are reported with example with their advantages and disadvantages. • Bioelectrode preparation from nanomaterials and conducting polymers are explained. • Summarized the current improvement in eBFCs along with their potential applications in implantable biomedical devices. [ABSTRACT FROM AUTHOR]

Abstract: Heat capacities and densities are significant in the design or the improvement of processes such as the blending of biofuels. An automated flow calorimeter, developed in our group, was used for the accurate measurement of isobaric heat capacities for pure compounds and mixtures over the range (250 to 400)K and (0 to 20)MPa. In this paper, isobaric heat capacities for cyclohexane and 1-hexene and their binary mixtures with ethanol are reported. Also the densities have been measured using an automated densimeter up to 70MPa. [Copyright &y& Elsevier]

Abstract: Biofuels can be alternative energy sources which simultaneously reduce dependence on fossil fuels and mitigate climate change by reducing greenhouse gas (GHG) emissions. In the US, over 50 billion liters of ethanol produced in 2010 is mandated to increase to 136 billion liters by 2022. Globally, approximately 33.3millionha (Mha) of land under production of biofuels in 2008 may increase to as much as 82Mha by 2020. Whereas data on the energy efficiency and GHG balances for biofuels are available, information on agronomic and ecological consequences of large-scale production of bioenergy crops is sparse. Thus, this paper describes the potential effects that bioenergy production may have on ecosystems. Conversion of land to biofuel crops may have significant impacts on ecosystem services such soil and water quality, GHG emissions, wildlife habitat, net primary productivity, and biological control, and plant diversity at both the landscape and the regional levels. Production of exotic species for feedstock may increase the risk of escape from agriculture and invasion into natural ecosystems. Several feedstocks, while suitable on the basis of energy and GHG assessments, may have negative ecosystem impacts (i.e., increased N export in the Gulf of Mexico). Bioenergy feedstock may compete with food crops for land, water, and nutrient resources, resulting in higher prices for food as well as potential increases in malnutrition and food insecurity. Biofuels can be a sustainable and renewable source of energy, but assessments must include ecological impacts, economic costs, and energetic efficiencies. [Copyright &y& Elsevier]

Abstract: This paper presents the derivation and partial analysis of a general producer–consumer model. The model is stoichiometric in that it includes the growth constraints imposed by species-specific biomass carbon to nutrient ratios. The model unifies the approaches of other studies in recent years, and is calibrated from an extensive review of the algae–Daphnia literature. Numerical simulations and bifurcation analysis are used to examine the impact of energy enrichment under nutrient and stoichiometric constraints. Our results suggest that the variety of system responses previously cited for related models can be attributed to the size of the total system nutrient pool, which is here assumed fixed. New, more complicated bifurcation sequences, such as multiple homoclinic bifurcations, are demonstrated as well. The mechanistic basis of the model permits us to show the robustness of the system’s dynamics subject to alternate approaches to modeling producer and consumer biomass production. [Copyright &y& Elsevier]

Abstract: Heat capacities are of great significance in the design of new processes and the improvement of existing ones in R&D in production plants as well as the adaptation of new products, in this case, biofuels to their use in a variety of engines and technical devices. An automated flow calorimeter has been developed for the accurate measurement of isobaric heat capacities for pure compounds and mixtures over the range (250 to 400)K and (0 to 20)MPa. In this paper, isobaric heat capacities for heptane, ethanol and the binary mixtures of ethanol with heptane and toluene are reported. [Copyright &y& Elsevier]

This paper presents the development of a new logistics model and its application to supply a mixture of agricultural feedstocks to a proposed cellulosic ethanol plant. The new model, IBSAL-MC (Integrated Biomass Supply Analysis &Logistics– Multi Crop), is developed based on the framework of IBSAL. IBSAL-MC is a hybrid push-pull logistics model which pushes the field operations to harvest and collect as much biomass as possible within the harvest season while pulling downstream operations to meet the daily demand of the ethanol plant. The proposed ethanol plant would be located near Prince Albert, Saskatchewan, Canada. Despite the abundance of wheat straw in the region (more than five times the annual demand), the daily demand of the ethanol plant would be fully met for only 104 days. In terms of the total annual demand, only 92% of it would be met. The logistics cost varies between $62.06 and $63.46t−1 with 90% confidence level. The capacity of the required on-farm storage and at-plant storage are estimated at 400 t and 3500 t of biomass, respectively. Several managerial insights were also given to improve the biomass logistics system in terms of demand fulfilment, logistics costs and resource utilisation. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides evidence of market power in the transportation of ethanol used in reformulated gasoline and alternative transportation fuels. I estimate a reduced form model for railroad route-level prices. My identification strategy instruments for railroad entry, controls for selection and explicitly models capacity constraints. A detailed understanding of this industry is important because U.S. environmental policies seek to substantially expand ethanol use. Evidence of market power may alter the types of policies pursued by lawmakers. I find that ethanol shipment prices are lower for more competitive routes. I also find evidence that railroads price discriminate based on environmental regulation at route destinations. Monopolist prices for shipments to carbon monoxide non-attainment areas are 3% higher than shipments to other destinations. This price premium falls sharply with increased competition. This suggests a perverse result where environmental regulation increases the price of a clean input. [Copyright &y& Elsevier]

Abstract: Efficient generation of a fermentable hydrolysate is a primary necessity in the utilization of fibrous plant biomass as a feedstock in bioethanol processes. Enzyme catalyzed hydrolysis of cellulose and heteroxylans in biomass feedstocks each require multiple enzyme activities to achieve degradation to fermentable monosaccharides. The minimal enzyme cocktail concept concerns identification of the minimal number, the minimal levels, and the optimal combination of the best performing key monoactive enzymatic activities to meet this requirement. Two major hypotheses lie behind this concept: 1. That the native multi-component profiles of crude “wild type” cellulolytic and/or xylan degrading enzyme preparations are not optimal for degradation of cellulose in pre-treated lignocellulosic biomass nor for degradation of heteroxylans in hemicellulose-rich product streams; 2. That it is possible to replace crude multienzyme preparations with designed combinations of the minimal number of required enzyme activities for biomass processing. This paper outlines the current strategies employed and the stage of development of minimal enzyme cocktails for enzymatic hydrolysis of cellulose and arabino-xylan in complex, genuine biomass substrates. The available data demonstrate the feasibility of the concept and illustrate the potential efficacy improvements obtainable by use of designed minimal enzyme cocktails for pre-treated lignocellulosic and hemicellulose-rich biomass substrates. [Copyright &y& Elsevier]

Abstract: The aim of this paper was to propose a granulation mechanism in order to interpret all the experimental observations that arose during experiments on two UASB reactors, where one was supplemented with ferrous iron at a dose of 0.01g Fe2+ per g COD feed. This supplementation with ferrous iron allowed COD removal of more than 98% at a loading rate of 9g COD/L per day, which was 24% higher than for the reactor not receiving the ferrous iron. Moreover, in the Fe2+-dosed reactor, a higher increase of the granule diameter was observed. Indeed, the granule diameter in the Fe2+-dosed reactor at the end of the experiments was 56% greater than that of the control reactor. This mechanism describes the course of anaerobic granule growth. The formation of the inorganic precipitate of ferrous sulphide constitutes the inert nuclei around which the biomass is attached. This initiates the formation of new granules. [Copyright &y& Elsevier]

Abstract: Currently, the predominant microbially produced biofuel is starch- or sugar-derived ethanol. However, ethanol is not an ideal fuel molecule, and lignocellulosic feedstocks are considerably more abundant than both starch and sugar. Thus, many improvements in both the feedstock and the fuel have been proposed. In this paper, we examine the prospects for bioproduction of four second-generation biofuels (n-butanol, 2-butanol, terpenoids, or higher lipids) from four feedstocks (sugars and starches, lignocellulosics, syngas, and atmospheric carbon dioxide). The principal obstacle to commercial production of these fuels is that microbial catalysts of robust yields, productivities, and titers have yet to be developed. Suitable microbial hosts for biofuel production must tolerate process stresses such as end-product toxicity and tolerance to fermentation inhibitors in order to achieve high yields and titers. We tested seven fast-growing host organisms for tolerance to production stresses, and discuss several metabolic engineering strategies for the improvement of biofuels production. [Copyright &y& Elsevier]

This paper aims to investigate the causal relationship among renewable energy technologies, biomass energy consumption, per capita GDP, and CO 2 emissions for Germany. We constructed an innovative algorithm, the Quantum model, and applied it with Machine Learning experiments – through a software capable of emulating a quantum system – to data over the period of 1990–2018. This process is possible after eliminating the "irreversibility" of classical computations (unitary transformations) by making the process "reversible". The empirical findings support the powerful role of biomass energy in reducing carbon dioxide emissions, although the effect of renewable energy technology displays a much stronger magnitude. Moreover, income remains an important determinant of environmental pollution in Germany. • An innovative Machine Learning algorithm (the Quantum model) has been constructed and applied. • The empirical findings support the powerful role of biomass energy in reducing CO 2 emissions. • GDP represents an important determinant of environmental pollution in Germany. [ABSTRACT FROM AUTHOR]

Abstract The importance of water pollutants on human health has been the subject of intense study and constitutes perhaps the most significant grand challenge for the future of human society. Water remediation faces many challenges in effectively combating pollution, especially for low income populations where poor water sanitation and little to no access to technically competent and cost effective remediation are nearly insurmountable issues. In an effort to provide low-cost adsorbents, research over the last few years has focused on biological residual materials from plants and animal biomass to not only to add value, but to remediate water at a lower cost with the same or improved efficiency as commercially available option. Crustacean shells are among a class of biological residues that are commonly treated as a waste product of the sea food industry. However, potential valorization by remediation of heavy metal ions, organic matter, and anionic species is a topic of high interest in the current eco-friendly environment. The aim of this review is to provide insight on the state of the art of crustacean shells for addressing water remediation and to offer some perspective regarding challenges and the future of this type of biomass. Highlights • Water remediation is one of the biggest challenges facing the health and future well-being of our global population. • Biosorption is a versatile, flexible cost-effective process. • Biosorption needs to be explored to overcome barriers associated with technical feasibility and potential as a competitor to synthetic adsorbents in the market. • The proposed review article is focused on providing a state-of-the-art for crustacean shells for biosorbent materials. [ABSTRACT FROM AUTHOR]