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This paper is devoted to research in the field of mining operations. Under the conditions of Ukraine΄s steppe zone the extraction of minerals is important. To minimize the consequences of coal mining, the disturbed soils were re-cultivated, thus minimizing the effect of toxic compounds, which are contained in mining rock, on human beings and the majority of soil biota representatives and it was taken care that these compounds do not get into the rehabilitated soil. This research focuses on the vitality of rehabilitated soil as a sustainable agricultural system. Earthworms (Lumbricidae) are the primary decomposers of organic material; their role in soils is to improve natural soil and/or artificially created soil. This paper studies the possible influence of different variants of substrates used in re-cultivating the representatives of soil saprophages. [ABSTRACT FROM AUTHOR]

This paper shows how much carbon-free energy might ultimately be available at the global scale. It is based on the international reports and incorporates data from our more recent research. The paper examines cost, capacity, advantages and disadvantages of hydropower, nuclear fission, biomass, wind, geothermal, solar and ocean energy. It highlights which sources make most sense. [ABSTRACT FROM AUTHOR]

Exciting recent developments in the enzymology and molecular biology of plant phenylpropanoids offer numerous opportunities to re-engineer the composition of plant biomass. Two main targets of such modifications are the optimized production of valuable compounds and reductions in the levels of less desirable products, such as the structural biopolymeric lignins. For example, the amounts of lignin biopolymers in (woody) species might be reduced, with carbon flow concurrently redirected toward production of related nonpolymeric phenylpropanoids, such as the more valuable allyl/propenyl phenols (e.g., eugenol, chavicol). Lignins are monolignol-derived polymeric end-products of the phenylpropanoid pathway (originating from the amino acids phenylalanine and tyrosine). In general, lignins represent a formidable technical challenge, particularly due to their intractable nature, for improved plant biomass utilization, for example, when considering the use of woody biomass for bioethanol production, as well as for wood, pulp, and paper manufacture. Other species-specific outcomes of the phenylpropanoid pathway, however, include metabolites such as lignans, flavonoids, and allyl/propenyl phenols. The recent discovery of the biochemical pathway resulting in the production of the more valuable liquid allyl/propenyl phenols (e.g., eugenol, chavicol, estragole, and anethole), important components of plant spice aromas and flavors, presents one potential approach to the engineering of plant metabolism in new directions. These compounds are synthesized from monolignols in two consecutive enzymatic reactions: (1) acylation of the terminal (C-9) oxygen of the monolignol forming an ester and (2) regiospecific, NAD(P)H-dependent reduction of the phenylpropanoid side chain with displacement of the carboxylate ester as leaving group. The proteins involved in the latter step are homologous to well-characterized phenylpropanoid reductases (pinoresinol-lariciresinol, isoflavone, phenylcoumaran-benzylic ether, and leucoanthocyanidin reductases), with similar catalytic mechanisms being operative. The proteins (and corresponding genes) involved in these transformations have been isolated and characterized and offer the potential of engineering plants to partially redirect carbon flow from lignin (or lignans) into these liquid volatile compounds in oilseeds, leafy or heartwood-forming tissues, or woody stems. The emerging knowledge could also potentially facilitate wood processing in pulp/paper industries and offer sources of renewable plant-derived biofuels, intermediate chemicals in polymer industries, or specialty chemicals in perfume and flavor industries. [ABSTRACT FROM AUTHOR]

The effect of varying initial particle sizes on enzymatic hydrolysis rates and rheological properties of sawdust slurries is investigated. Slurries with four particle size ranges (33 μm < x ≤ 75 μm, 150 μm < x ≤ 180 μm 295 μm < x ≤ 425 μm, and 590 μm < x ≤ 850 μm) were subjected to enzymatic hydrolysis using an enzyme dosage of filter paper units per gram of cellulose at 50°C and 250 rpm in shaker flasks. At lower initial particle sizes, higher enzymatic reaction rates and conversions of cellulose to glucose were observed. After 72 h 50 and 55% more glucose was produced from the smallest size particles than the largest size ones, for initial solids concentration of 10 and 13% (w/w), respectively. The effect of initial particle size on viscosity over a range of shear was also investigated. For equivalent initial solids concentration, smaller particle sizes result in lower viscosities such that at a concentration of 10% (w/w), the viscosity decreased from 3000 cP for 150 μm < x ≤ 180 μm particle size slurries to 61.4 cP for 33 μm < x ≤ 75 μm particle size slurries. Results indicate particle size reduction may provide a means for reducing the long residence time required for the enzymatic hydrolysis step in the conversion of biomass to ethanol. Furthermore, the corresponding reduction in viscosity may allow for higher solids loading and reduced reactor sizes during large-scale processing. [ABSTRACT FROM AUTHOR]

Plant materials from the vegetative growth stage of reed canarygrass and the seed stage of reed canarygrass are pretreated by ammonia fiber expansion (AFEX) and enzymatically hydrolyzed using 15 filter paper units (FPU) cellulase/g glucan to evaluate glucose and xylose yields. Percent conversions of glucose and xylose, effects of temperature and ammonia loading, and hydrolysis profiles are analyzed to determine the most effective AFEX treatment condition for each of the selected materials. The controls used in this study were untreated samples of each biomass material. All pretreatment conditions tested enhanced enzyme digestibility and improved sugar conversions for reed canarygrass compared with their untreated counterparts. Based on 168 h hydrolysis results using 15 FPU Spezyme CP cellulase/g glucan the most effective AFEX treatment conditions were determined as: vegetative growth stage of reed canarygrass–100°C, 60% moisture content, 1.2:1 kg ammonia/kg of dry matter (86% glucose and 78% xylose) and seed stage of reed canarygrass–100°C, 60% moisture content, 0.8:1 kg ammonia/kg of dry matter (89% glucose and 81% xylose). Supplementation by commercial Multifect 720 xylanase along with cellulase further increased both glucose and xylose yields by 10–12% at the most effective AFEX conditions. [ABSTRACT FROM AUTHOR]

The biomass flash pyrolysis, as the advanced technology of thermo-chemical conversion of biomass, can convert low-grade biomass energy to high-grade biomass energy, the main characteristic of which is that the percent of biological oil in the terminal products is very large. The biological oil is an ideal clean fuel, which can substitute diesel oil and the gasoline for the power oil after suitable re-processing. In order to obtain large amount of liquid production (biological oil) yield, an experiment was carried out in this paper. Using sawdust as biomass and fluidized bed as the reactor, this experiment investigated the relationship between the quantity of three kinds of products (the liquid, the gas, and the solid) and the final reaction temperature. In the experiment, only the temperature in the fluidized bed were changed, the other parameters remained stable, such as the quantity of the feeding, the remaining time of the gas product, the amount of fluidized wind, the pressure of the system, and the bed height, and so on. The experiment equipments and process were presented in this paper, with productivity as a function of temperature and curve type, and found that biological oil yields can reach the maximum when the reaction temperature is in the range of 450°C∼540.7°C. This investigation shows that the reaction temperature of biomass flash pyrolysis has a decisive influence on the type and size of the products. The study presents a reference to device design and technological process of transformation from biomass to biomass energy. [ABSTRACT FROM AUTHOR]

China is an agriculture country. Biomass resource will be up to 65 hundred million ton per year. On the assumption that average heating value is 15000kJ/kg, those biomass resources are equivalent to 33 hundred million ton standard coal, and equivalent to 1.8 double annual total energy consumption in China. Biomass fuel is a kind of renewable energy. In this paper, basal compositions of multi-representative biomass fuel were studied, especially analyzed on the effects on combustion characteristics of composition changes of molding corn stalk. The air consumption, triatomic gas and flue gas of unit mass of corn stalk all are under those of general soft coal, therefore, air supply and air distribution of corn stalk combustion are obviously different from those of general soft coal. Combustion experiments were adopted on the grate boiler, and the results indicated that under the specific air distribution, molding corn stalk could meet the need of combustion. [ABSTRACT FROM AUTHOR]

The use of bioenergy for the generation of electricity and heat, as well as for the production of biofuels, is growing at an impressive pace. While some ecological advantages of the use of biomass are well-known, critics stress the negative ecological and social impacts of intensive use of biomass. Existing legal regulations, whether on a European or national level, do not seem to solve these problems. The role sustainability criteria play in overcoming the ambivalences of global bioenergy use naturally is a limited one, as these criteria are not suited to accurately reflecting the complexity of the matter. Also, sustainability criteria may not avoid effects of shifting or indirect land-use, i.e. the production of e.g. meat or non-regulated biomass instead of regulated biomass in areas that do not match sustainability criteria. Finally, some of the most important aspects, as for example the world΄s nourishment problems, are not representable at all in sustainability criteria – and especially not in the current EU criteria. Instead, a radical policy shift to energy efficiency and strict greenhouse gas caps would prove a lot more effective in overcoming these ambivalences in the use of bioenergy. A far-reaching policy of energy efficiency and strict caps would reduce global energy consumption and thus lead the way to a future zero carbon economy run exclusively on renewable energies. The text analyses the ambivalences of the use of bioenergy and at the same time provides a short overview of the law of bioenergy in the EU (also including some aspects of WTO law). [ABSTRACT FROM AUTHOR]

In Serbian National Energy Strategy it is clearly stated that one of the main directives in upcoming years will be substitution of conventional fossil fuels with renewable sources. This opens up prospects for development of new business ideas for utilization of Serbian biomass resources which will undoubtedly contribute towards lessening domestic dependence on imported fossil fuels and consequently their environmental impact. Wood and agricultural biomass play key role in this as a two most important biomass resources in Serbia. The paper depicts the current situation and proposes options for future action. [ABSTRACT FROM AUTHOR]

This paper outlines anticipated climate change impacts on energy systems. It presents a set of indicators to determine: the level of vulnerability of a particular energy system; the capacity to implement energy adaptation projects; and how successful proposed implementation measures will be in increasing energy system resilience. Wind, solar, hydro, biomass, nuclear and fossil fuel energy systems are addressed. [ABSTRACT FROM AUTHOR]

Ambience is an important parameter for gasification, which can affect characteristics of syngas notably. A lab-scale fixed-bed furnace is set up and biomass is gasified at 600°C in different ambience. In ambiences of N2, yields of CO2, H2, CH4 and CO reach 255 ml/g, 144 ml/g, 70 ml/g, and 131 ml/g respectively, and yield of char is 147ml/g. In ambience of CO2, the produce of CO2 is restrained while produce of CO is facilitated, which conduces to extra oxygen combined with hydrogen and produces more H2O rather than H2. In ambience of H2O, water-gas shift reaction occurs at low temperature and more CO, CO2 and H2 are produced. In ambience of N2+O2, oxidation is the predominant reaction. In mixed ambience, the oxidation reaction is restrained by ambient gas obviously. [ABSTRACT FROM AUTHOR]

The article presents an introduction for the concern around carbon dioxide emission reduction and biomass with lignite co-combustion.

Purpose-grown trees will be part of the bioenergy solution in the United States, especially in the Southeast where plantation forestry is prevalent and -economically important. Trees provide a ˵living biomass inventory″ with existing end-use markets and associated infrastructure, unlike other biomass species such as perennial grasses. The economic feasibility of utilizing tree biomass is improved by increasing productivity through alternative silvicultural systems, improved breeding and biotechnology. Traditional breeding and selection, as well as the introduction of genes for improved growth and stress tolerance, have enabled high growth rates and improved site adaptability in trees grown for industrial applications. An example is the biotechnology-aided improvement of a highly productive tropical Eucalyptus hybrid, Eucalyptus grandis × Eucalyptus urophylla. This tree has acquired freeze tolerance by the introduction of a plant transcription factor that up-regulates the cold-response pathways and makes possible commercial plantings in the Southeastern United States. Transgenic trees with reduced lignin, modified lignin, or increased cellulose and hemicellulose will improve the efficiency of feedstock conversion into biofuels. Reduced lignin trees have been shown to improve efficiency in the pre-treatment step utilized in fermentation systems for biofuels production from lignocellulosics. For systems in which thermochemical or gasification approaches are utilized, increased density will be an important trait, while increased lignin might be a desired trait for direct firing or co-firing of wood for energy. Trees developed through biotechnology, like all transgenic plants, need to go through the regulatory process, which involves biosafety and risk assessment analyses prior to commercialization. [ABSTRACT FROM AUTHOR]

In this chapter we briefly trace the historical debate and outline the theoretical and empirical evidence for factors controlling the biomass of predators, herbivores, and plants within and among ecosystems. [ABSTRACT FROM PUBLISHER]

Biomass from plant material is the most abundant and widespread renewable raw material for sustainable development, and can be employed as a source of polymeric and oligomeric carbohydrates. When ingested as a part of the diet, some biomass polysaccharides and/or their oligomeric hydrolysis products are selectively fermented in the colon, causing prebiotic effects. [ABSTRACT FROM AUTHOR]

Hydrogen is considered as a novel fuel for the twenty first century, mainly due to its environmentally benign character. Production of hydrogen from renewable biomass has several advantages compared to that of fossil fuels. A number of processes are being practiced for efficient and economic conversion and utilization of biomass to hydrogen. This article updates the developments of various hydrogen-production processes from biomass. Several developmental works are discussed, with a brief outline of different technologies employed therein. A comparative study of existing processes is given on the basis of their relative merits and demerits. [ABSTRACT FROM AUTHOR]

In all oil consumption dependent countries the shift from fossil fuels to bio-based ones plays a prominent role in public discussions and political decision making. However, the discussion all too often singles out biomass as a new energy source without paying due respect to the system aspects and constraints. Biomass can indeed be a valuable element of a new energy mix, but without structural change in the energy system it poses risks to biodiversity and food security. Agricultural energy production either competes with food production on existing agricultural areas, or with biodiversity preservation if pristine areas are used for biomass production. Thus exploiting the potential of biomass for energy generation needs to t environmental and social limits, and must be adapted to the specifics of the local situation if it is to be a part of the solution, and not the source of new problems. [ABSTRACT FROM AUTHOR]

At present time, new advances in the generation of computational models can be applied to improve tasks in different areas of research. The hybrid computational models can be considered as new advances in science. In the present work a hybrid model has been proposed on the basis of a cellular automata and fuzzy logic to simulate, in space and time, the dynamics of a population structured by ages and where the changes in the levels of the biomass are induced by a stochastic variation of the environment. The model can be used as computational tool in the area of the Biology to describe and quantify the changes that continuously occurs in the population, knowing not only their size and its structure, but the form and the intensity in which it changes and renews. [ABSTRACT FROM AUTHOR]

Distillers dried grain with solubles (DDGS) is the major coproduct produced at a dry grind ethanol facility. Currently, it is sold primarily as a ruminant animal feed. DDGS is low cost and relatively high in protein and fiber contents. In this study, DDGS was investigated as carbon source for extracellular hydrolytic enzyme production. Two filamentous fungi, noted for their high cellulolytic and hemicellulolytic enzyme titers, were grown on DDGS: Trichoderma reesei Rut C-30 and Aspergillus niger NRRL 2001. DDGS was either used as delivered from the plant (untreated) or after being pretreated with hot water. Both microorganisms secreted a broad range of enzymes when grown on DDGS. Higher xylanase titers were obtained when cultured on hot water DDGS compared with growth on untreated DDGS. Maximum xylanase titers were produced in 4 d for A. niger and 8 d for T. reesei in shake flask cultures. Larger amounts of enzymes were produced in bioreactors (5L) either equipped with Rushton (for T. reesei) or updraft marine impellers (A. niger). Initial production titers were lower for bioreactor than for flask cultures, especially for T. reesei cultures. Improvement of enzyme titers were obtained using fed-batch feeding schemes. [ABSTRACT FROM AUTHOR]

Ensilage can be used to store lignocellulosic biomass before industrial bioprocessing. This study investigated the impacts of seven commerical enzyme mixtures derived from Aspergillus niger, Trichoderma reesei, and T. longibrachiatum. Treatments included three size grades of corn stover, two enzyme levels (1.67 and 5 IU/g dry matter based on hemicellulase), and various ratios of cellulase to hemicellulase (C : H). The highest C : H ratio tested, 2.38, derived from T. reesei, resulted in the most effective fermentation, with lactic acid as the dominant product. Enzymatic activity during storage may complement industrial pretreatment; creating synergies that could reduce total bioconversion costs. [ABSTRACT FROM AUTHOR]

Olive tree pruning generates an abundant, renewable lignocellulose residue, which is usually burnt on fields to prevent propagation of vegetal diseases, causing economic costs and environmental concerns. As a first step in an alternative use to produce fuel ethanol, this work is aimed to study the pretreatment of olive tree pruning residues by liquid hot water. Pretreatment was carried out at seven temperature levels in the range 170–230°C for 10 or 60 min. Sugar recoveries in both solid and liquid fractions resulting from pretreatment as well as enzymatic hydrolysis yield of the solid were used to evaluate pretreatment performance. Results show that the enzyme accessibility of cellulose in the pretreated solid fraction increased with pretreatment time and temperature, although sugar degradation in the liquid fraction was concomitantly higher. [ABSTRACT FROM AUTHOR]

Clostridium thermocellum is an anaerobic, thermophilic bacterium that can directly convert cellulosic substrates into ethanol. Microarray technology is a powerful tool to gain insights into cellular processes by examining gene expression under various physiological states. Oligonucleotide microarray probes were designed for 96.7% of the 3163 C. thermocellum ATCC 27405 candidate protein-encoding genes and then a partial-genome microarray containing 70 C. thermocellum specific probes was constructed and evaluated. We detected a signal-to-noise ratio of three with as little as 1.0 ng of genomic DNA and only low signals from negative control probes (nonclostridial DNA), indicating the probes were sensitive and specific. In order to further test the specificity of the array we amplified and hybridized 10 C. thermocellum polymerase chain reaction products that represented different genes and found gene specific hybridization in each case. We also constructed a whole-genome microarray and prepared total cellular RNA from the same point in early-logarithmic growth phase from two technical replicates during cellobiose fermentation. The reliability of the microarray data was assessed by cohybridization of labeled complementary DNA from the cellobiose fermentation samples and the pattern of hybridization revealed a linear correlation. These results taken together suggest that our oligonucleotide probe set can be used for sensitive and specific C. thermocellum transcriptomic studies in the future. [ABSTRACT FROM AUTHOR]

This work investigated the combustion phenomena of solid fuels, coal and wood pellets with use of high temperature oxidizers (873 –1273 K), both in oxygen diluted and oxygen enriched conditions. The combustion process and flame are described and mass, temperature and heating rate as function of time for different oxidizer compositions and temperature are discussed. The results show that high temperature conditions give the highest mass loss rates. The influence of oxygen concentration on mass loss rate is more evidenced for enriched conditions and/or lower oxidizer temperatures. Diluted conditions are associated with large flames while a typical flame downstream from the sample was almost absent for oxygen concentrations above 50%. Ignition time is highly dependent on oxygen concentration only when a 873 K oxidizer was used while almost independent when a 1273 K oxidizer was used. [ABSTRACT FROM AUTHOR]

Biomass pyrolysis equipment designed independently consists of feeding system with two-stage screw feeder, fluidized bed reactor, cyclone separator system, condensation system and control system. Fluidized bed reactor is taken numerical simulation by CFD software FLUENT. The system is optimized based on numerical simulation and preliminary test. The gas distribution equipment is installed at the bottom of the fluidized bed, which makes gas distributed more uniformly and reduces the resistance of fluid-flow. The appropriate service conditions are determined based on numerical simulation. The fluidization velocity is about 2.35m/s. The yield of bio-oil is between 40% and 58%. It is favorable for further process to get the bio-oil by fractional condensation. The experimental results show that this test equipment has the excellences such as brief structure, simple and convenient operation, low energy consumption, and it is prone industrialization. [ABSTRACT FROM AUTHOR]

Biomass is a possible alternative to the direct use of fossil fuel energy. Especially, Biomass plays an important role in China which has abundant biomass resources. The theories of biomass thermo-chemical conversion were introduced and on the basis of theoretical results utilization technologies of biomass were elaborated in Zhejiang University which included combustion, gasification and liquefaction. Based on lots of work on mechanism of straw combustion and small and bench scale experiments, a new developed technology is specially design for high-alkali biomass combustion in CHP scale. With Developed Biomass Gasification Technology the medium heat value gas (MCV) has supplied to the households in Wenzhou Demo Plant Project. A fluidized bed reactor with 20kg/h throughput operating at an atmospheric pressure with an inert atmosphere at 773 K has been used to produce bio-oils. At optimum pyrolysis conditions maximum bio-oil yield of up to 60% was obtained. The quality of the bio-oil produced remains poor, and a combination of high value products and energy applications were needed for profitability. [ABSTRACT FROM AUTHOR]

Concern about the state of our environment has slowly worked its way up the political agenda over the last decade or so. This new awareness exists on many levels: there are global issues such as climate change, local problems such as traffic congestion, as well as health worries caused by toxic waste and air pollution. Biological processes, such as photosynthesis, helped to shape our environment in the early days of evolution, as we shall see in Chapter 12. The aim of environmental biotechnology is to use the transforming power of biochemistry – driven, of course, by DNA – to help to create an environment that we would be proud to leave to our grandchildren. There are two main ways in which biotechnology can soften the impact of human activity on our planet. It can help in the provision of energy and material resources, and in the destruction of pollution. Trapping energy from the Sun As the world's population grows, so do people's aspirations. Hence many people in developing countries want the cars, fridges and other objects that we take for granted in the Western world. At the same time, they also want to develop their industries to generate income and a higher standard of living. Inevitably this will result in increased energy consumption – from more electricity to drive domestic and industrial appliances to more fuel for heating and transport. Today the commercial energy market is dominated by coal, oil and gas – the fossil fuels. [ABSTRACT FROM AUTHOR]