Geochemical characteristics of major and trace elements in Sahinali Coals,Aydin, Turkey

In this study, geochemical behavior of elements is investigated in 25 coal samples collected at 10 locations of ?ahinli coaliferous units at southeast of Ayd?n, Turkey. In all the samples, X-ray powder diffraction and inductively coupled plasma mass spectrometry analyses were performed and element and mineral compositions were determined. Total organic carbon (TOC) values of coals are between 14.6 and 37.7 wt% with average of 28.5 wt%. Samples are composed of quartz, calcite, feldspar, dolomite, mica, gypsum, and salt minerals which are accompanied by illite-, kaolinite-, and smectite-type clay minerals. Comparison of average element contents of world coals and studied samples yields that K > Fe > As > U > Cs > Y > Er > Al > Th > Rb > Yb > W > Tb > Dy > Lu > Ce > Sm > La > Ho > Si > Nd > Gd > Tm > Eu > Nb > Pr > Pb > Sn > Ni > Cu > Ga > Ta > Sb > Zr > Cd > V > Zn > Co > Mo > P > Hf > Ba are found to be enriched, while Mn > Be > Ca > Sr > Bi > Mg are found to be depleted. Statistically elements are correlated with TOC.     

燃煤锅炉PM10排放及元素分布特性的实验研究

应用低压撞击器对某300 MW燃煤锅炉除尘器前后的飞灰颗粒进行采样,对飞灰颗粒的质量粒径分布、除尘器对不同粒径颗粒的除尘效率和元素Si、Al、Fe、Ca、Mg、S、Cu、Pb、Zn、Mn的分布富集规律进行了研究,结果表明该电站除尘器前后PM_(10)质量粒径分布及元素质量分布均呈双峰分布,其峰值分别在0．1μm和2．36～3．95μm附近．除尘器对不同粒径颗粒的收集效率差别很大,对粒径大于10μm颗粒的收集效率约为100%,而对亚微米颗粒的收集效率在62%～83%之间．元素Mg、S、Cu、Zn和Pb在小粒径的飞灰颗粒上有明显富集趋势,特别是元素Cu、Zn和Pb,其相对富集系数达30～40,Si、Al和Ca的富集系数与粒径成正比变化,而Fe和Mn的富集系数与粒径没有规律性变化．     

Influence of Coal Ash and Slag Dumping on Dump Waste Waters of the Kostolac Power Plants (Serbia)

The content of selected trace and major elements in the river water used for transport, as well as in the subcategories of the waste waters (overflow and drainage) were analyzed in order to establish the influence of transport and dumping of coal ash and slag from the “Kostolac A” and “Kostolac B” power plants located 100 km from Belgrade (Serbia). It was found that during transport of coal ash and slag to the dump, the water used for transport becomes enriched with manganese, nickel, zinc, chromium, vanadium, titanium, cobalt, arsenic, aluminum, and silicon, while more calcium, iron, cadmium, and lead are adsorbed by the ash and slag than is released from them. There is also an equilibrium between the release and adsorption processes of copper and magnesium during transport. The vertical penetration of the water used for transport results in a release of calcium, magnesium, manganese, and cadmium to the environment, while iron, nickel, zinc, chromium, copper, lead, vanadium, titanium, cobalt, and arsenic are adsorbed by the fractions of coal ash and slag in the dump.     

Source Rock Characterization and Depositional Environment of the Late Cretaceous Haymana Formation in the Salt Lake Basin of Turkey

Abstract

Late Campanian-Maestrichtian Haymana Formation of the Salt Lake Basin, Turkey was deposited in a forearch Basin. This formation has been studied by a combination of organic geochemical methods (LECO/Rock-Eval, sulphur, gas chromatography), light microscopy, and bulk combination method (elemental analysis) in order to assess the hydrocarbon source potential of the abundant and extensive shale intervals presents in the formation.

The shales have an organic carbon content (TOC) up to 1.69% and hydrogen index (HI) values up to 380. Pyrolysis yields (TOC, S ₂, and HI) and organic petrography (kerogen type, amount%) indicate that the shales are dominantly gas potential, containing Type III and II organic matter. Thermal maturity, assessed from Spore Colour Index and T _max, indicates that late Campanian-Maestrichtian Haymana Formation in the Salt Lake Basin range from diagenetic to over mature with respect to oil generation and may produce gas and oil.

The values for the V/Cr ratio of shales vary from 0.29 to 3.20, indicating dysoxic and anoxic conditions for bottom water.     

The effects of solid absorbents on the emission of trace elements,SO2, and NOx during coal combustion

The emission of toxic metals from the combustion of fossil fuels is an important global environmental issue. Solid absorbents can be used to control the emission of toxic trace elements from coal combustion. In this paper, limestone, CaSO₄, bauxite, kaolinite and CaO are employed for this purpose and experiments are carried out in an electrically heated drop‐tube furnace. The trace elements investigated are Pb, Cd, Cr and As. It is observed that the absorptive capacity is related to the qualities of the absorbents (type, amount and particle size) and the combustion temperature. The results also show that some absorbents can reduce SO₂ emission simultaneously, but no influence on NO_x emission. Copyright © 2001 John Wiley & Sons, Ltd.     

Characterization of heavy metal trace elements in the fly ash from a thermal power plant

The disposal of fly ash in the thermal power plant is a challenging task. With the increase in the demand of the coal as fuel in thermal power plants, combustion products, such as coal ash, become a serious environmental problem due to their leaching characteristics. The objective of the present study was to investigate the leaching characteristics of the fly ash disposed in ash pond of thermal power plants. A series of leaching tests have been performed with different liquid-to-solid (L/S) ratio. The L/S ratio varies from 20:1 to 60:1. It is observed that the elements, such as Mn, Mg, Cr, Zn, Ni, Pb, Fe, and Cu, are most abundant elements, while Mo and Co are the least abundant elements. It is also observed that the leaching characteristics of the fly ash are affected by the pH of extraction solution and liquid-to-solid (L/S) ratio.     

煤中易挥发痕量元素赋存形态的分析方法及实验研究

讨论并比较了煤中痕量元素赋存形态的分析方法及其应用范围，应用逐级化学提取法对3种典型煤进行浸提，根据易挥发痕量元素不同形态的溶解度，将煤中砷、汞、硒分为可交换态、硫化物结合态、有机物结合态和残渣态。结果表明，砷在煤中主要以硫化物结合态存在，汞在煤中主要以硫化物结合态和残渣态存在，硒赋存在硫化物、有机物和残渣态中，不同煤种中易挥发痕量元素各种形态的分布不同，应用浮沉法将煤按不同密度分级后，分别测定了各级煤粉中砷、汞含量，表明砷、汞主要存在于煤的矿物质中。     

Partitioning of rare earths and some major elements in the Kizildere geothermal field, Turkey

Rare earth elements and yttrium (REY), Na⁺, K⁺, Cl⁻, and Ca²⁺ were determined in water, steam, mineral scale and rock samples from the Kizildere geothermal field, Turkey. The CO₂-rich parent fluid originates from a sequence of mica schists with marble intercalations. The chemistry of the parent fluid varies with location and time. The average REY composition of the fluids is derived by extrapolation to the lowest Ca concentrations. The apparent vapor–liquid partitioning factors for REY at 145 °C and 5 bar total absolute pressure are about 0.2, whereas for Ca²⁺, Na⁺, K⁺ and Cl⁻ they are <0.05, about 0.0005, 0.0005 and about 0.02, respectively. Apparent scale-liquid distribution coefficients for REY at 145 and 190 °C are about 0.15 and 0.55, whereas at 100 °C they increase from 0.3 (La) to 1.5 (Lu).     

Platinum group elements in terrestrial oil shale from the Lunpola Basin,northern Tibet,China

The Lunpola oil shale is the largest oil shale resource in Tibet. Twenty-four samples were collected from this deposition to determine the platinum group element (PGE) characteristics. The total PGE contents in terrestrial oil shale are low (average 2.386 ng/g). The PGEs are enriched in the oil shale samples near the boundary between the oil shale and its underlying strata. The PGE enrichment may be the result of a change of oxic–anoxic conditions. The individual PGEs of oil shale samples from the Lunpola oil shale exhibit similar modes of occurrence, and their distributions are controlled mainly by Fe-bearing minerals (pyrite). The source of PGEs in the Lunpola oil shale is probably related to water chemistry and terrigenous supply.     

Petrography of Feed Coals in the Soma Power Plant,Manisa, Turkey

The coal-bearing Soma basin is one of the most productive lacustrine coal basins of western Anatolia-Turkey. This study mainly focuses on petrography of the feed coals (FCs) in the Soma power plant. A total of 16 feed coal samples were systematically collected once a week over an eight-week period from both group boiler units, B1–4 with 660 MW and B5–6 with 330 MW capacity. The most abundant maceral group of FCs is huminite, in which texto-ulminite, eu-ulminite, attrinite, densinite are rich. Liptinite group macerals in FCs include mainly sporinite, resinite, and liptodetrinite, which are considerably higher than the other identified liptinite macerals. In the inertinite group, fusinite and inertodetrinite are more abundant. Identifiable minerals with petrographical studies are pyrite, siderite, other minerals (e.g., carbonates, clay minerals, quartz, feldspar, etc.), and fossil shells. This study shows that FCs used are subbituminous in rank with mean random ulminite reflectance of 0.43%Rr oil from B1–4 units and 0.39%Rr oil from B5–6 units. This indicates that coal rank is slightly higher in the central mines (southern Soma) than in the Denis mines (northern Soma).     

Energy conversion efficiency of trout and sea bass production in the Black Sea,Turkey

This study examined the current energy balance, energy conversion efficiency, and farm-level efficiency of trout and sea bass production in the Black Sea of Turkey. Using a structured survey, we collected data from nine monoculture trout farms and five polyculture trout and sea bass farms during the 2005–2006 production season. Energy values were calculated using energy equivalents of the inputs and outputs for the farms. Data envelopment analysis was used to calculate farm-level efficiency. The total energy use per cubic meter was 46.57 MJ for trout production and 87.13 MJ for sea bass production. The main energy inputs were feed and diesel oil for both trout and sea bass production. Indirect energy use was dominant in trout production, while direct energy use was more common in sea bass production. The energy input-to-output ratio of trout production was higher than that of sea bass production. Sea bass production was more economically energy efficient compared to trout production. The allocative and economic energy efficiencies for trout and sea bass production were 0.788 and 0.881, respectively. For both types of farms, the most discriminative variable affecting economic efficiency was operator experience. Increasing focus on product distribution costs could decrease total energy costs by approximately 12%.     

Determining the effect of trace elements on biohydrogen production from fruit and vegetable wastes

Trace elements are one of the important parameters for dark fermentative H₂ production because they work as co-factors in H₂ formation biochemistry. Lack or excess of trace element and its concentrations could be an important reason for the low yield of H₂ production. In this study, the effects of 11 different trace elements (Fe, Ni, Zn, Co, Cu, Mn, Al, B, Se, Mo and W) were tested at two levels in terms of biohydrogen production from Fruit and Vegetable Wastes (FVW) with Biochemical Hydrogen Potential (BHP) Tests using Plackett-Burman statistical design. 1.1–2.8 times enhancement of biohydrogen production was determined with its addition. The most effective trace elements were found as Zn and Ni. In order to reveal the resident microbial flora, Denaturing Gradient Gel Electrophoresis (DGGE) analysis was carried out on all BHP effluent samples. Results of DGGE analysis, four microbial sequences evaluated as Clostridium sp., Clostridium baratii, Uncultured bacterium, Uncultured Streptococcus sp., and their similarity rates were 99%, 100%, 89%, 98%, respectively.     

燃煤过程中元素Na和Fe在可吸人颗粒物中的形态与分布

通过对平顶山烟煤在沉降炉内的燃烧试验,结合热力学平衡计算分析,研究了两种选定的矿物质成灰元素Na和Fe在可吸入颗粒物中的形态与分布。燃烧试验条件为:煤粉粒径小于63μm,燃烧温度在1400°C,炉内燃烧气氛为空气气氛。试验采用低压撞击器(LPI)按不同粒径大小从0.03~10μm共分为13级,分别采集燃烧后的可吸入颗粒物。并采用热力学平衡计算分析方法研究了氧化性气氛中元素Na和Fe的化学形态和物理相。试验和计算结果显示:钠元素主要以Na单质的形式气化,大部分以NaO、Na2SO4、NaCl、Na3PO4的形式存在于亚微米颗粒中,极少量以NaAlSi3O8相存在于PM1.0-10中;Fe元素主要以FeO的形式气化,部分以Fe2O3的形式存在于亚微米颗粒中,部分以Fe3O4和Fe2O3的形式存在于PM1.0-10中。图1表2参6     

Research on the generation of electricity from the geothermal resources in Simav region, Turkey

One of the greatest problems in using renewable energy sources is the great variability of energy level, both in the short and long term. Geothermal energy, by nature, has high availability because the source is not dependent on weather conditions, so it is among the most stable renewable energy sources. Geothermal energy has the potential to play an important role in the future energy supply of Turkey. Although Turkey has the second-highest geothermal energy potential in Europe, electricity generation from geothermal energy is rather low.This study examines the use of geothermal energy in electricity generation and investigates the applicability of the existent geothermal energy resources to electricity generation in the Kütahya–Simav region, Turkey. The binary cycle is used in the designed power plant for electricity generation from geothermal fluid in which the percentage of liquid is high and which is at lower temperature. In this power plant, R134a is chosen as the secondary fluid, whose boiling point temperature is lower than that of water, and is used instead of geothermal fluid in a second cycle. The thermal efficiency of the designed power plant is measured to be 12.93%.     

Quantitative characterization of middle-high ranked coal reservoirs in the Hancheng Block,eastern margin,Ordos Basin,China: implications for permeability evolution with the coal macrolithotypes

Macrolithotypes control the pore-fracture distribution heterogeneity in coal impacting the coalbed methane (CBM) production from the reservoir. However, few studies have focused on the characteristics of macrolithotypes. Here, the macrolithotype samples from the three continuous seams (No. 3, 5 and 11) in the Hancheng Block, Ordos Basin, China were quantitatively characterized by multiple length scales. The results indicate that the bright coal has the best development of micro-fracture than those of the other macrolithotypes, which with good openness and connectivity under the optical microscopy; N₂ adsorption/desorption results reflect that the adsorption pores of the semi-dull and dull coal are more developed than the bright coal and semi-bright coal, and are dominated by plate-like and ink-bottle pores. The characteristics of the mercury intrusion/extrusion curves were determined by the mercury injection (MIP). From bright to dull coal the pore connectivity being worse, and the uniformity of pore and throats distribution becomes lower. The pore type that divided by NMR are recovered to be seepage type (the bright), comprehensive type (the semi-bright and semi-dull), and the type of adsorption (the dull). The behavioral differences would impact the porosity and permeability in coal. Thus, by the well logging evaluation approach, the relationship between coal macrolithotypes and select logging parameters were determined for coal macrolithotype identification, and with the petrel software included, the porosity-permeability models were built to investigate the permeability evolution with the coal macrolithotypes. Macrolithotypes are closely related to the permeability of coal reservoirs in this area. The greater contribution of permeability is typically from of the bright and semi-bright coal, and followed by semi-dull and dull coal, the better development of bright coal, the better permeability of the reservoir and vice versa.     

Molecular hydrogen from organic sources in the deep Songliao Basin,P.R. China

Free hydrogen detected in the Songke-2 well (Songliao Basin, China) has a strong crustal contribution. Here we evaluate whether the source could be the organic matter in Lower Cretaceous coals and shales, and extend our findings regionally. We could establish the rapid growth of aromatic ring systems, forming hydrogen, methane and pyrobitumen, using high resolution mass spectrometry. Molecular hydrogen is generated after late hydrocarbon gas generation is complete, concluding at R_r = 5.0%. The kinetic parameters of molecular hydrogen formation were constructed by subtracting the hydrogen associated with hydrocarbon formation from the total hydrogen, as measured by extensive open system pyrolysis experiments. This new insight was achieved using a CH₄–H₂ stoichiometric balance. Generalised calculations indicate that the yield per unit rock volume closely resembles that of economic shale gas in the Barnett Shale, though storage in organic matrices is unlikely in this depositional setting. While the prolific generation of hydrogen from organic sources appears to be a reality in the Songliao basin, the free H₂ in the Songke-2 mudstream coming from this source must most likely have migrated into the basement rocks mainly from lateral equivalents of the Shahezi rather than from the drilled section itself.     

京津冀地区农村煤改气现状及减排潜力分析

对京津冀农村地区煤改气现状进行研究,并对当前采用的经济环境效益评价方法加以归纳,以近年来颁布的国家及地方政策为辅助依据估算农村燃煤减排潜力。根据计算结果,对比SO2、NOx、CO、PM10、PM2.5在三地区的减排效果得出,北京减排效果最明显,天津及河北省有明显改善;由减排分布得到,SO2、NOx、CO、PM10、PM2.5在北京市、天津市、河北省减排潜力分布中各占3%、1%、85%、6%和5%。由此看出,通过减少农村散煤使用来控制污染物排放量的方法具有良好的发展前景。然后进一步剖析当前出现的问题,以努力推进农村减排工作。     

Distributions of environmentally hazardous elements in the Tertiary oil shale deposits from NW Anatolia,Turkey: A statistical analysis

The environmentally hazardous element concentrations (As, Cd, Cr, Cu, Hg, Mn, Pb, S, and Zn) and element–organic matter relations of the oil shale deposits in six different fields in NW Anatolia, Turkey, were investigated and the characteristics of fields were compared. The enrichment factor (EF) for most of the trace elements in the studied oil shales generally show enrichment patterns for all the fields. Only Cr, Hg, and Pb for oil shale samples from the Bahçecik field samples and Hg for oil shale samples from the Gölpazar? field samples are depleted. Arsenic in the Bahçecik field samples and Hg in the Himmeto?lu field samples are neither depleted nor enriched. The lowest and highest element enrichments in these fields are determined to be Hg and S, respectively. In general, all elements have high concentrations in the Beypazar? and Seyitömer fields and low concentrations in the Himmeto?lu, Bahçecik, and Gölpazar? (except for As) fields. A positive correlation at significance level of p ≤ 0.05 was observed for total organic carbon content with Cd in four of the fields, with Cu and S in two fields and with Cr, Mn, and Zn in only one field.     

Vapour/liquid fractionation of rare earths,Y, Na,K, NH4, Cl,HCO3, SO4 and borate in fluids from the Piancastagnaio geothermal field,Italy

Vapour/liquid fractionation of rare earth elements and yttrium (REY), Na⁺, K⁺, NH₄⁺, HCO₃⁻, SO₄²⁻, Cl⁻ and borate in geothermal fluids from the Piancastagnaio geothermal field (Mt. Amiata geothermal area, Tuscany, central Italy) were evaluated based on the chemistry of collected liquids and condensed vapours. Apparent vapour–liquid partitioning factors (^appD^V/L) of REY vary from 0.3 to 0.01. These factors are much higher than those of Na (<0.001) and K (∼0.001). Volatile components are ion pairings such as NH₄HCO₃^o, NH₄Cl^o, NaHCO₃^o, CaSO₄^o and REYO(HCO)₃^o ⇔ REY(OH)CO₃^o. In vapour, REY and NH₄⁺ are negatively correlated. High and low ^appD^V/L(REY) indicate variations of NH₄⁺ concentrations in liquids. The results of this study are relevant to the understanding of element migration and deposition under hydrothermal boiling conditions.