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Number of results: 56
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Abstract

The aim of this study was to compare and analyze the gasification process of beech wood. The experimental investigation was conducted inside a gasifier, which can be operated in downdraft and updraft gasification system. The most important operating parameter studied in this paper was the influence of the amount of supply air on the temperature distribution, biomass consumption and syngas calorific value. The results show that the amount of air significantly influences the temperature in the combustion zone for the downdraft gasification process, where temperature differences reached more than 150 ◦C.The increased amount of air supplied to the gasifier caused an increase in fuel consumption for both experimental setups. Experimental results regarding equivalence ratio show that for value below 0.2, the updraft gasification is characterized by a higher calorific value of producer gas, while for about 0.22 a similar calorific value (6.5 MJ/Nm3) for both gasification configurations was obtained. Above this value, an increase in equivalence ratio causes a decrease in the calorific value of gas for downdraft and updraft gasifiers.
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Abstract

Petrographic and physico-chemical analyses of ashes are carried out on a large scale and presented in numerous scientific papers. The mentioned ashes are obtained from filters and electrostatic precipitators mounted in large industrial installations. The large-scale analysis of the ashes obtained directly from grate furnaces or blast furnaces mounted in low-power boilers started with combating smog and low-stack emissions. The collection of ash samples from household furnaces usually involves the analysis of the combustion of waste in low-power boilers. This is justified in the case of old type boilers, which were designed to use virtually any fuel. Currently, new types of boilers, designed to burn dedicated fuels, are offered on the market. The aim is to use only renewable fuels (biomass) or fossil fuels with high quality parameters, which are more environment-friendly, e.g. eco-pea coal, lignite briquettes, or peat briquettes. The authors of the study focused on examining the ash obtained from boilers for burning wood pellets by performing microscopic analysis of residues after biomass combustion. The above mentioned analysis provides a comprehensive information on the efficiency of the combustion process, the content of contaminants remaining in the ash, and the suitability of ash for other applications. The entire process, from the moment of collecting the samples to the execution of the analysis takes up to 12 hours, which ensures a quick decision on furnace adjustment or fuel change. The ash components were determined based on the results obtained by the Fly-Ash Working Group of the International Committee for Coal and Organic Petrology (ICCP). The mentioned classification has been supplemented with new key elements occurring in ashes resulting from the combustion of wood pellets in household boilers. This allowed determining the percentage content of characteristic components in the tested material, which can be used as a specific benchmark when issuing opinions on the quality and efficiency of the boiler and the combusted pellets.
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Abstract

On the basis of acoustically registered cross-sections of krill aggregations, regular, irregular and layer forms were distinguished. Regular forms are most frequently observed during spring and in the day time, while irregular forms are most frequent during summer and night hours. The density histograms made for two hour intervals clearly show the day-night difference, but the seasonal (spring, summer) difference is less pronounced. Mean density of swarm is lowest during the night and reaches a maximum in early morning hours. The mean volume backscattering strength values (Sv) for spring and summer are nearly identical. We suggest that regular forms correspond to foraging swarms and irregular forms to feeding swarms as described by Hamner (1984).
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Abstract

24 species of 8 fish families were found to occur on the shelf of Elephant Island during austral spring and summer of 1986/87 season. Notothenia gibberifrons was a predominant species (78—83% per catch). The presence of Champsocephalus gunnari and Chaenocephalus aceratus (15—20% per catch) almost completed fish composition profile. A pronounced decrease of Notothenia rossi (0.03—0.04% per catch) was noticed. Some specimens of Champsocephalus gunnari were characterized by a spawning-time shifted by almost half a year comparing to the remaining part of its population.
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Abstract

The chlorophyll a content was measured at 62 oceanographic stations. At each station samples were collected from eight standard depths between the water surface and 150 m. Integrated values (chlorophyll α mg/m2) are used in the presentation of the results and discussion. The recorded quantities of chlorophyll α were rather high, amounting to as much as 634 mg/m2. The areas with high chlorophyll a content (> 200 mg/m2) were located in the region of the Anvers Island and Brabant Island, on the shelf around Joinville Island and opposite the Antarctic Sound, close to Clarence Island and beyond the regions recommended in the BIOMASS-SIBEX programme to the east and south of the South Orkney Islands. In the acetonie extracts of photosynthetizing pigments large quantities of phytoxanthin were found using the TLC method, what precludes the use of the Lorenzen method for determination of chlorophyll α and its degradation products.
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Abstract

The material discussed in this paper was collected in the Drake Passage and Bransfield Strait (Antarctica) within the framework of the BIOMASS-SIBEX programme. Samples were collected by hauling Nansen nets verticaly through the 100 — 0, 300—100 and 500 — 300 m layers in December 1983 and January 1984. Of the six species recorded — Metaconchoecia isocheira, Alacia hettacra, Alacia belgicae, Metaconchoecia skogsbergi, Boroecia antipoda and Discoconchoecia off. elegans — the first three, endemic to Antarctic waters — were predominant (92.9%). Ostracoda were found most abundantly in the eastern part of the study area — between Elephant Island and South Orkney Islands, and in the south-western part of Bransfield Strait. Their vertical distribution depended on the hydrological conditions. Ostracoda were most numerous in the 500—300 m and 300 — 100 m layers; very few were recorded in the 100—0 m surface layer.
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Abstract

During the BIOMASS-SIBEX Antarctic expedition the distribution of Copepoda in three water layers (0—100, 100—300 and 300—500 m) in the Bransfield Strait and southern Drake Passage was studied. Altogether 46 taxa were recorded (Tabs. 1 and 2); the number of taxa increased with depth. Faunistic differences between the Drake Passage and the Bransfield Strait were observed. In some species the age-related splitting of the populations was registered (Figs. 2, 3 and 4). Young generations occupied usually the upper water layers.
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Abstract

The changes in the domestic solid fuel market (including forecasted increases in the fuel prices) and the growing requirements related to actual environmental standards, result in increased interest in renewable energy sources, such as biomass, wind and solar energy. These sources will allow to achieve reduction in the CO2 emission, and consequently – avoid environmental costs after 2020. Therefore, the development of distributed energy systems, based on the use of biomass boilers, gas boilers and high efficiency combined heat and power units, will enable the fulfillment of current standards in the field of energy efficiency and emission of pollutants to the atmosphere. It should be emphasized that the actions taken to reduce emissions (e.g. anti-smog act) will contribute to reducing coal consumption in the municipal and housing sector (households, agriculture and other customers) in favor of biomass and other renewable energy sources. The article reviews selected biomass technologies: - fluidized, dust and grate boilers, - straw-fired boilers, - cogeneration systems powered by biomass, - torrefaction and biomass carbonisation. The mentioned technologies are characterized by a high potential of in the field of dynamic development and practical application in the coming years. Thus, they can improve difficult situation in the distributed energy sector with a capacity up to 50 MW.
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Abstract

During the SIBEX1' programme in December 1983/January 1984, 27 hauls were made from the "Profesor Siedlecki" with a 368 — mesh midwater sampling trwal. A total of 13 fish species at postlarval or juvenile stages was found in the catches. The greatest aboundance and species diversity of juvenile ichthyofauna was observed within shelf waters of the Peninsula. Postlarval and juvenile Pleuragramma antarcticum was the most common and most aboundant species there.
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Abstract

Hydrological conditions in the region between the King George and Elephant Islands were defined on the basis of 24 STD measurements and 20 XBT profiles made in the time period from 26 October to 16 November 1986. In the entire investigated region the surface water temperature was below zero, often close to freezing point. The presence of summer modification of surface water with its characteristic thermal minimum was not found. Between the Scotia Front and the relatively well pronounced stream of geostrophic currents the anticyclonic meander was observed above the edge of the shelf at the depth of 100 m. Its spread was about 10 nM and within this meander the downwelling of surface water was noticed. As a compensating water movement, the upwelling of warmer waters was observed in the Drake Passage at 400 m.
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Abstract

Zooplankton in the water column from the surface to bottom was studied. Copepods were the dominating organisms. Average zooplankton biomass was about 5 g in 1000 m3 . The highest zooplankton density occurred between 300 and 600 m. The influence of the Scotia Front on the horizontal and vertical distribution of zooplankton is discussed.
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Abstract

The distribution of pelagic Polychaeta in the Scotia Front region is presented. 6 polychaete taxa were recorded in the material with the most abundant Pelagobia longicirrata which constituted 86% of all collected specimens. The mixing of water masses in the frontal zone influence the quantitative distribution of polychaetes in the water column.
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Abstract

In the planktonie material collected using a Nansen net (vertical hauls) larvae of two euphausiid species were found. The dominant and occurring in all stations were larvae of Thysanoessa macrura. Following larval stages were encountered: nauplius, metanauplius, calyptopis I and calyptopis II. The most numerous and occurring in the widest depth spectrum were calyptopes I. Only twice furcilia VI of Euphausia superba were found. The distribution of euphausiid larvae was influenced by the stratification and circulation of water masses in the investigated area.
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Abstract

Results of hydroacoustic investigations of krill biomass carried out in the South Shetland Island region between October 1986 and January 1987 are presented. A considerable difference in the krill biomass between Antarctic spring and summer was recorded. Initially observations were conducted close to Elephant Island, in the period just after the retreated of compact ice cover. Krill then aggregated only in swarms, the density of which frequently exceeded 100 t nM-2 . In the region of Polygon I (30—31 October 1986) the total estimated biomass was 26899 t, in the region of Polygon II (6—10 November 1986) it was 25827 t. Investigations were repeated in January 1987 obtaining 112372 t in the Bransfield Strait and 390309 t in the region of Elephant Island. The results are presented in tables and maps.
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Abstract

On the basis of hydroacoustic observations it is shown that migrations of krill during spring are stronger than during summer. Migrations of krill are described by the function: H(t) = A + Bcos((2ᴨt/T + φ ) + C c o s ( 2 ᴨt/T + φ ), where: H is depth of the mass center of krill biomass, A — mean depth of krill occurrence, В — amplitude of migrations with period T! = 24 h, С — amplitude of migrations with period T2 = 12 h, (φ1, φ2 — phases of migration process with T, = 24 and T2 = 12 hours. Parameters of the equation are the following: spring — A = 62.2 m, В = 19.5 m, С = 4.6 m, φ1 = 0.1 h, φ2 = 0 . 1 5 h; summer — A = 75.8 m, В = 0.5 m, С = 3.6 m, φ1 = 1.8 h, φ2 = 6.4 h.
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Abstract

In the region of the Admiralty Bay 12 nesting bird species were encountered of a total abundance of 40890 pairs and biomass amounting to about 395000 kg Three penguin species constituted 91.7% in abundance, their biomass constituting 98.7% of the whole community. Densities of abundance and biomass of adult birds in relation to the living area of penguins (i.e. 775 km2) ranged from 32.3 to 121.4 indiv. km-2 and from 115.1 to 4730 kg k m-2.
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Abstract

Biomass is one of the most frequently used sources of renewable energy. For centuries, wood has been used by people to heat their homes, and nowadays it is also used to generate electricity. The article discusses legal issues related to biomass, classification of biomass for energy purposes, quality parameters of selected ecological fuels, quality requirements for biomass, as well as biomass trade in the world. The article compares the quality requirements for biomass purchased by individual companies from the power sector (mainly dimensions, calorific value, moisture content, ash content, sulfur and chlorine). An analysis of the price of wood pellets on international markets, represented by the biomass stock exchanges: RBCN, EEX and BALTPOOL was also performed. The market analysis clearly shows that the international market for industrial pellets is dominated by intercontinental trade, which mainly concerns exchanges between the United States of America as a producer and Europe as a consumer. The largest amount of biomass is imported by the United Kingdom, mainly for its Drax biomass power plant, and this biomass comes from the USA and Canada. In addition to Great Britain, significant importers of wood pellets are the Netherlands, Belgium and Denmark. Judging by the interest of Polish energy companies in the purchase of biomass, also in Poland, the development of the biomass market should be expected.
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Abstract

Two field experimental trials were carried out in central Italy, in 2005 and 2006, on biomass sorghum [Sorghum bicolor (L.) Moench] in order to assess weed control efficacy and selectivity to the crop of some pre- and post-emergence herbicides applied at different doses and in different mixtures. All herbicides showed good selectivity to the crop, although postemergence treatments showed higher transitory phytotoxicity effects than pre-emergence treatments, especially when high temperatures occurred after treatments, decreasing the selectivity of leaf herbicides (i.e. MCPA, 2,4-D, bromoxynil and dicamba). Considering pre-emergence applications, terbuthylazine alone against broadleaves or in mixtures at low doses with s-metolachlor against mixed infestations (grasses + broadleaves), seemed to be the best options to obtain a good selectivity to the sorghum and a high weed control level. Aclonifen showed some limits in terms of weed spectrum and could be recommended only against simplified broadleaf weed infestations without the presence of less susceptible weeds, like Amaranthus retroflexus, Portulaca oleracea and Solanum nigrum. Propachlor seemed not to be advisable due to the low efficacy against all the major broadleaf warmseason weed species in the Mediterranean areas. Considering post-emergence applications, all treatments gave quite similar results in terms of weed control, although, the mixture of terbuthylazine + bromoxynil seemed to be the best option due to bromoxinil’s higher efficacy than other foliar herbicides, such as MCPA, 2,4-D and dicamba, which can increase the efficacy of terbuthylazine alone especially under dry weather conditions. There were no significant differences in sorghum biomass between herbicide treatments, although, the more selective pre-emergence treatments showed, on average, a higher biomass yield value than the less selective post-emergence treatments. For these reasons, biomass values seemed to be more related to herbicide selectivity than to herbicide efficacy, especially in cases of scarce competitiveness of weed flora.
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Abstract

Results of the study examining carbon monoxide and nitric oxide concentrations while burning different types of agricultural biomass: coffee husk pellets alone or in combination with wheat straw pellets and cherry stones, sewage sludge pellets, corn stover briquettes and a mixture of rye straw briquettes and miscanthus briquettes were presented. The combustion was performed in a 50 kW boiler type Biowarmer with a cast-iron moving step grate. The temperature in the combustion chamber did not exceed 800 ◦C. For all biomass types, only brittle slag was generated in the furnace, which was easily broken by a reciprocating movement of the grate. Carbon monoxide concentration in the flue gas except for the case of sewage sludge pellet firing did not exceed the permitted value of 3000 mg/m3 and nitric oxide concentration 515 mg/m3, both presented for 10% O2 concentration in the flue gas based in dry gas. Hydrocarbon concentrations for all test runs were close to zero.
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Abstract

Due to the significant role of macrophytes in the functioning of lake ecosystems studies have been undertaken to examine whether mutual dependence is present within emergent, floating-leaved, and submerged aquatic macrophytes. The study included 5 small lakes from Polesie Lubelskie region. The research included: qualitative analysis of macrophytes (area occupied by macrophytes, composition, range of individual plant groups of occurrence), quantitative analysis of macrophytes (biomass of macrophytes inhabiting the lake), analysis of distribution as well as characteristics diversity of shoreline and surrounding land use. Because of differences in the environmental conditions, mostly light availability, usage of buffer zone, among the three macrophyte groups, changes in biomass were analyzed in this work suggests that complementarity not competition drive the community. This phenomenon seems to occur only in macrophyte lakes where all three groups are present and the surrounding buffer zones remain natural. In lakes where one of the three groups of macrophytes were missing, it is likely that the ecological roles are fulfilled by other plant groups, such as phytoplankton. The studied lakes represent both phytoplanton and macrophyte type of lakes.
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Abstract

Sewage and solid waste can be a valuable source of materials used directly or indirectly in manufacturing of usable products. These processes are associated with elimination of pollutants from liquid and solid wastes. The best-known methods of waste management are production of biogas and composting. This paper focuses on the possibility of obtaining biomass as a source of protein feed (whose value, in terms of the composition of aminoacids and microelements, is comparable with conventional feed, e.g. soymeal, bonemeal or fishmeal). Sewage components for bacterial, fungal, algal and vascular plants’ culture are characterized as a source of protein feed. Methods of industrial scale production of enzymes, mainly proteases and lipases that have broad applications in various industries, are discussed. Development perspectives of inexpensive methods of usable products from waste production are showed. Interdisciplinary nature of presented issues, which requires cooperation of specialists in biology, chemistry and technology, is emphasized.
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Abstract

Soils that have been exposed to flood waters can be heavily polluted by inorganic and organic compounds. They are mainly compounds which appear in dissolved or suspended form flowing together with heavily laden floodwater, as well as compounds created as a result of reactions in the soil profile, mostly due to anaerobic transformation of organic matter. Heavy metals brought with flood waters are absorbed by the soil and also washed out from flood sediments by precipitation when the flood recedes. This paper presents the results of research on the effects of fertilization with ash from incineration or pyrolysis of biomass on the migration process of heavy metals (Zn, Cu, Cr, Ni, Pb, Cd, Mn) in the arable layer of soil. It has been shown that the metals in the flood sediment migrate actively in the soil profile what leads to the enrichment of the soils, also in the case of the soil fertilization with biomass ash.
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Abstract

The aim of the conducted research was to determine the possibilities of using the biomass of macroalgae obtained from Puck Bay during May-September season in biogas production process. Model respirometry chambers were used to determine the amount of produced biogas and examine its quality composition. Depending on the month in which the algal biomass was obtained, the experiments were divided into five stages. In each stage, the effectiveness of the biogas production process was tested for the applied loads in model fermentation chambers in the range from 1.0 kg DOM/m3 · d to 3.0 kg DOM/m3 · d. During the experiments it was found that the efficiency of biogas production varied from 205 dm3/kg DOM to 407 dm3/kg DOM depending on the month of the vegetation season and the applied organic matter load in the chamber. Methane content was very high and ranged from 63% to 74%.
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Abstract

The use of biomass in the energy industry is the consequence of ongoing efforts to replace Energy from fossil fuels with energy from renewable sources. However, due to the diversity of the biomass, its use as a solid fuel generates waste with diverse and unstable chemical composition. Waste from biomass combustion is a raw material with a very diverse composition, even in the case of using only one type of biomass. The content of individual elements in fly ash from the combustion of biomass ranges from zero to tens of percent. This makes it difficult to determine the optimal recovery methods. The ashes from the combustion of biomass are most commonly used in the production of building materials and agriculture. This article presents the elemental composition of the most commonly used biomass fuels. The results of the analysis of elemental composition of fly ashes from the combustion of forest and agricultural biomass in fluidized bed boilers used in the commercial power industry were presented. These ashes are characterized by a high content of calcium (12.3–19.4%), silicon (1.2–8.3%), potassium (0.05–1.46%), chlorine (1.1–6.1%), and iron (0.8–6.5%). The discussed ashes contained no sodium. Aluminum was found only in one of the five ashes. Manganese, chromium, copper, nickel, lead, zinc, sulfur, bismuth, titanium and zirconium were found in all of the examined ashes. The analysis of elemental composition may allow for a preliminary assessment of the recovery potential of a given ash.
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