WorldWideScience

Sample records for coal reservoir characteristics

  1. Reservoir characteristics of coal-shale sedimentary sequence in coal-bearing strata and their implications for the accumulation of unconventional gas

    Science.gov (United States)

    Wang, Yang; Zhu, Yanming; Liu, Yu; Chen, Shangbin

    2018-04-01

    Shale gas and coalbed methane (CBM) are both considered unconventional natural gas and are becoming increasingly important energy resources. In coal-bearing strata, coal and shale are vertically adjacent as coal and shale are continuously deposited. Research on the reservoir characteristics of coal-shale sedimentary sequences is important for CBM and coal-bearing shale gas exploration. In this study, a total of 71 samples were collected, including coal samples (total organic carbon (TOC) content >40%), carbonaceous shale samples (TOC content: 6%-10%), and shale samples (TOC content TOC content. Clay and quartz also have a great effect on the porosity of shale samples. According to the FE-SEM image technique, nanoscale pores in the organic matter of coal samples are much more developed compared with shale samples. For shales with low TOC, inorganic minerals provide more pores than organic matter. In addition, TOC content has a positive relationship with methane adsorption capacity, and the adsorption capacity of coal samples is more sensitive than the shale samples to temperature.

  2. Advances in coalbed methane reservoirs using integrated reservoir characterization and hydraulic fracturing in Karaganda coal basin, Kazakhstan

    Science.gov (United States)

    Ivakhnenko, Aleksandr; Aimukhan, Adina; Kenshimova, Aida; Mullagaliyev, Fandus; Akbarov, Erlan; Mullagaliyeva, Lylia; Kabirova, Svetlana; Almukhametov, Azamat

    2017-04-01

    Coalbed methane from Karaganda coal basin is considered to be an unconventional source of energy for the Central and Eastern parts of Kazakhstan. These regions are situated far away from the main traditional sources of oil and gas related to Precaspian petroleum basin. Coalbed methane fields in Karaganda coal basin are characterized by geological and structural complexity. Majority of production zones were characterized by high methane content and extremely low coal permeability. The coal reservoirs also contained a considerable natural system of primary, secondary, and tertiary fractures that were usually capable to accommodate passing fluid during hydraulic fracturing process. However, after closing was often observed coal formation damage including the loss of fluids, migration of fines and higher pressures required to treat formation than were expected. Unusual or less expected reservoir characteristics and values of properties of the coal reservoir might be the cause of the unusual occurred patterns in obtained fracturing, such as lithological peculiarities, rock mechanical properties and previous natural fracture systems in the coals. Based on these properties we found that during the drilling and fracturing of the coal-induced fractures have great sensitivity to complex reservoir lithology and stress profiles, as well as changes of those stresses. In order to have a successful program of hydraulic fracturing and avoid unnecessary fracturing anomalies we applied integrated reservoir characterization to monitor key parameters. In addition to logging data, core sample analysis was applied for coalbed methane reservoirs to observe dependence tiny lithological variations through the magnetic susceptibility values and their relation to permeability together with expected principal stress. The values of magnetic susceptibility were measured by the core logging sensor, which is equipped with the probe that provides volume magnetic susceptibility parameters

  3. Structural Characteristics and Physical Properties of Tectonically Deformed Coals

    OpenAIRE

    Yiwen Ju; Zhifeng Yan; Xiaoshi Li; Quanlin Hou; Wenjing Zhang; Lizhi Fang; Liye Yu; Mingming Wei

    2012-01-01

    Different mechanisms of deformation could make different influence on inner structure and physical properties of tectonically deformed coal (TDC) reservoirs. This paper discusses the relationship between macromolecular structure and physical properties of the Huaibei-Huainan coal mine areas in southern North China. The macromolecular structure and pore characteristics are systematically investigated by using techniques such as X-ray diffraction (XRD), high-resolution transmission electron mic...

  4. Study on Transfer Rules of Coal Reservoir Pressure Drop Based on Coalbed Methane Well Drainage Experiments

    Science.gov (United States)

    Yuhang, X.

    2017-12-01

    A pumping test was carried out to explore the transfer rules of pressure drop in coal reservoir during the drainage. The experiment was divided into three stages. In the first stage, the pump displacement of 3m3/h was used to reduce the bottom hole flowing pressure and stopped until the continuous gas phase was produced; Undertaking the first stage, in the second stage, when the gas phase was continuously produced, the pump was stopped immediately. As the bottom hole flowing pressure going up without gas phase, pumping started again for a week. In the third stage ,the well pumping was carried out at the bottom hole pressure drop rate of 30Kpa/d after two months' recovery. Combined with the data of regional geology and fractured well, taking the characteristics of macroscopic coal rocks, development of pore and fracture in coal and isothermal adsorption test as the background, the features of reservoir output in each stage of the experiment were analyzed and compared, and then the transfer rules of pressure drop contained in the differences of the output was studied further. In the first and third stage of the experiment, the output of liquid phase was much larger than the space volume of coal reservoir pore and fracture in the range of 100m2. In the second stage, the output of the continuous gas phase appeared around 0.7Mpa when the continuous gas phase appears below the critical desorption pressure of 0.25Mpa during the whole experiment. The results indicate that, the transfer of pressure drop in the coal reservoir of this well is mainly horizontal, and the liquid phase produced in the reservoir mainly comes from the recharge of the reservoir at the far end of the relative high pressure area; the adsorption space of coalbed methane in the coal matrix as well as the main migration channel of fluid in the reservoir doesn't belong to the same pressure system and there exists the communication barrier between them. In addition, the increasing of the effective stress

  5. The Characteristics of Spanish Reservoirs

    National Research Council Canada - National Science Library

    Armengol, J; Merce, R

    2003-01-01

    Sau Reservoir was first filled in 1963 in a middle stretch of the Ter River, as part of a multi-use scheme, including hydroelectric power, agricultural irrigation, domestic and industrial water supply...

  6. Stochastic reservoir simulation for the modeling of uncertainty in coal seam degasification

    Science.gov (United States)

    Karacan, C. Özgen; Olea, Ricardo A.

    2015-01-01

    Coal seam degasification improves coal mine safety by reducing the gas content of coal seams and also by generating added value as an energy source. Coal seam reservoir simulation is one of the most effective ways to help with these two main objectives. As in all modeling and simulation studies, how the reservoir is defined and whether observed productions can be predicted are important considerations.

  7. Geochemical characteristics of Carboniferous-Permian coal-formed gas in Bohai Bay Basin

    Energy Technology Data Exchange (ETDEWEB)

    Shipeng Huang; Fengrong Liao; Xiaoqi Wu [PetroChina, Beijing (China). Research Institute of Petroleum Exploration & Development

    2010-03-15

    Coal-formed gas reservoirs have been found in several depressions in Bohai Bay Basin. The gas was mainly generated by the Carboniferous-Permian coal measures, which are good source rocks. The exploration of coal-formed gas has a broad prospect. The main reservoirs of the coal-formed gas are Ordovician, Carboniferous-Permian, and Paleogene stratum. Coal-formed gas in the Bohai Bay Basin is chiefly composed of hydrocarbon gases. The percentage content of carbon dioxide is more than that of the nitrogen gas. The stable carbon isotope values of the hydrocarbon gases of different depressions and different reservoirs usually reversed. The reversed values of gas samples account for 52.1% of all the samples. Reversion values of the carbon isotope are mainly because of the mixing of gases from same source rocks but with different maturity. Among the three main reservoirs, coal-formed gas preserved in Paleogene stratum has the heaviest carbon isotope, the second is the gas in Carboniferous-Permian stratum, and the Ordovician gas possesses the lightest carbon isotope. Based on the analysis of the characteristics of carbon isotope of hydrocarbon gases in well Qishen-1 and the distribution of the Carboniferous-Permian coal measures, the gas of the well is derived from the high-matured Carboniferous-Permian coal measures.

  8. Development and linearization of generalized material balance equation for coal bed methane reservoirs

    International Nuclear Information System (INIS)

    Penuela, G; Ordonez R, A; Bejarano, A

    1998-01-01

    A generalized material balance equation was presented at the Escuela de Petroleos de la Universidad Industrial de Santander for coal seam gas reservoirs based on Walsh's method, who worked in an analogous approach for oil and gas conventional reservoirs (Walsh, 1995). Our equation was based on twelve similar assumptions itemized by Walsh for his generalized expression for conventional reservoirs it was started from the same volume balance consideration and was finally reorganized like Walsh (1994) did. Because it is not expressed in terms of traditional (P/Z) plots, as proposed by King (1990), it allows to perform a lot of quantitative and qualitative analyses. It was also demonstrated that the existent equations are only particular cases of the generalized expression evaluated under certain restrictions. This equation is applicable to coal seam gas reservoirs in saturated, equilibrium and under saturated conditions, and to any type of coal beds without restriction on especial values of the constant diffusion

  9. Geological storage of carbon dioxide in the coal seams: from material to the reservoir

    International Nuclear Information System (INIS)

    Nikoosokhan, S.

    2012-01-01

    CO 2 emissions into the atmosphere are recognized to have a significant effect on global warming. Geological storage of CO 2 is widely regarded as an essential approach to reduce the impact of such emissions on the environment. Moreover, injecting carbon dioxide in coal bed methane reservoirs facilitates the recovery of the methane naturally present, a process known as enhanced coal bed methane recovery (ECBM). But the swelling of the coal matrix induced by the preferential adsorption by coal of carbon dioxide over the methane in place leads to a closure of the cleat system (a set of small natural fractures) of the reservoir and therefore to a loss of injectivity. This PhD thesis is dedicated to a study of how this injectivity evolves in presence of fluids. We derive two poro-mechanical dual-porosity models for a coal bed reservoir saturated by a pure fluid. The resulting constitutive equations enable to better understand and model the link between the injectivity of a coal seam and the adsorption-induced swelling of coal. For both models, the pore space of the reservoir is considered to be divided into the macroporous cleats and the pores of the coal matrix. The two models differ by how adsorption of fluid is taken into account: the first model is restricted to surface adsorption, while the second model can be applied for adsorption in a medium with a generic pore size distribution and thus in a microporous medium such as coal, in which adsorption mostly occurs by micropore filling. The latter model is calibrated on two coals with different sorption and swelling properties. We then perform simulations at various scales (Representative Elementary Volume, coal sample, coal seam). In particular, we validate our model on experimental data of adsorption-induced variations of permeability of coal. We also perform simulations of seams from which methane would be produced (CBM) or of methane-free seams into which CO 2 would be injected. We study the effect of various

  10. Characteristics of coal mine ventilation air flows.

    Science.gov (United States)

    Su, Shi; Chen, Hongwei; Teakle, Philip; Xue, Sheng

    2008-01-01

    Coal mine methane (CMM) is not only a greenhouse gas but also a wasted energy resource if not utilised. Underground coal mining is by far the most important source of fugitive methane emissions, and approximately 70% of all coal mining related methane is emitted to the atmosphere through mine ventilation air. Therefore, research and development on mine methane mitigation and utilisation now focuses on methane emitted from underground coal mines, in particular ventilation air methane (VAM) capture and utilisation. To date, most work has focused on the oxidation of very low concentration methane. These processes may be classified based on their combustion kinetic mechanisms into thermal oxidation and catalytic oxidation. VAM mitigation/utilisation technologies are generally divided into two basic categories: ancillary uses and principal uses. However, it is possible that the characteristics of ventilation air flows, for example the variations in methane concentration and the presence of certain compounds, which have not been reported so far, could make some potential VAM mitigation and utilisation technologies unfeasible if they cannot cope with the characteristics of mine site ventilation air flows. Therefore, it is important to understand the characteristics of mine ventilation air flows. Moreover, dust, hydrogen sulphide, sulphur dioxide, and other possible compounds emitted through mine ventilation air into the atmosphere are also pollutants. Therefore, this paper presents mine-site experimental results on the characteristics of mine ventilation air flows, including methane concentration and its variations, dust loadings, particle size, mineral matter of the dust, and other compounds in the ventilation air flows. The paper also discusses possible correlations between ventilation air characteristics and underground mining activities.

  11. A new method for calculating gas content of coal reservoirs with consideration of a micro-pore overpressure environment

    Directory of Open Access Journals (Sweden)

    Jinxing Song

    2017-05-01

    Full Text Available When the gas content of a coal reservoir is calculated, the reservoir pressure measured by well logging and well testing is generally used for inversion calculation instead of gas pressure. However, the calculation result is not accurate because the reservoir pressure is not equal to the gas pressure in overpressure environments. In this paper, coal samples of different ranks in Shanxi and Henan are collected for testing the capillary pressure of coal pores. Based on the formation process of CBM reservoirs and the hydrocarbon generation and expulsion history of coal beds, the forming mechanisms of micro-pore overpressure environments in coal reservoirs were analyzed. Accordingly, a new method for calculating the gas content of coal reservoirs with consideration of a micro-pore overpressure environment was developed. And it was used to calculate the gas content of No. 1 coal bed of the 2nd member of Lower Permian Shanxi Fm in the Zhongmacun Coal Mine in Jiaozuo, Henan. It is indicated that during the formation and evolution of coals, some solid organic matters were converted into gas and water, and gas–water contact is surely formed in pores. In the end, capillary pressure is generated, so the gas pressure in micro-pores is much higher than the hydrostatic column pressure, which results in a micro-pore overpressure environment. Under such an environment, gas pressure is higher than reservoir pressure, so the gas content of coal reservoirs calculated previously based on the conventional reservoir pressure evaluation are usually underestimated. It is also found that the micro-pore overpressure environment exerts a dominating effect on the CBM content calculation of 3–100 nm pores, especially that of 3–10 nm pores, but a little effect on that of pores >100 nm. In conclusion, this new method clarifies the pressure environment of CBM gas reservoirs, thereby ensuring the calculation accuracy of gas content of coal reservoirs.

  12. Microbial conversion of higher hydrocarbons to methane in oil and coal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Martin; Beckmaann, Sabrina; Siegert, Michael; Grundger, Friederike; Richnow, Hans [Geomicrobiology Group, Federal Institute for Geosciences and Natural Resources (Germany)

    2011-07-01

    In recent years, oil production has increased enormously but almost half of the oil now remaining is heavy/biodegraded and cannot be put into production. There is therefore a need for new technology and for diversification of energy sources. This paper discusses the microbial conversion of higher hydrocarbons to methane in oil and coal reservoirs. The objective of the study is to identify microbial and geochemical controls on methanogenesis in reservoirs. A graph shows the utilization of methane for various purposes in Germany from 1998 to 2007. A degradation process to convert coal to methane is shown using a flow chart. The process for converting oil to methane is also given. Controlling factors include elements such as Fe, nitrogen and sulfur. Atmospheric temperature and reservoir pressure and temperature also play an important role. From the study it can be concluded that isotopes of methane provide exploration tools for reservoir selection and alkanes and aromatic compounds provide enrichment cultures.

  13. Impacts of Natural Surfactant Soybean Phospholipid on Wettability of High-rank Coal Reservoir

    Science.gov (United States)

    Lyu, S.; Xiao, Y.; Yuan, M.; Wang, S.

    2017-12-01

    It is significant to change the surface wettability of coal rock with the surfactant in coal mining and coalbed methane exploitation. Soybean phospholipid (SP) is a kind of natural zwitterionic surfactant which is non-toxic and degradable. In order to study the effects of soybean phospholipid on wettability of high-rank coal in Qinshui Basin, some experiments including surface tension test, contact angle measurement on the coal surface, coal fines imbibition, observation of dispersion effect and gas permeability test were carried out, and water locking mechanism of fracturing fluid in micro fractures of coal reservoir was analyzed. The results show that the surface of high-rank coal was negatively charged in solution and of weak hydrophilicity. The soybean phospholipid with the mass fraction of 0.1% reduced the surface tension of water by 69%, and increased the wettability of coal. Meanwhile, the soybean phospholipid helped coal fines to disperse by observation of the filter cake with the scanning electron microscope. The rising rate of soybean phospholipid solution in the pipe filled with coal fines was lower than that of anionic and cationic surfactant, higher than that of clean water and non-ionic surfactant. Composite surfactant made up of soybean phospholipid and OP-10 at the ratio of 1:3 having a low surface tension and large contact angle, reduced the capillary force effectively, which could be conducive to discharge of fracturing fluid from coal reservoir micro fracture and improve the migration channels of gas. Therefore it has a broad application prospect.

  14. Washability characteristics of residual coals obtained from solvent extraction: studies towards developing cleaner coal technology

    Energy Technology Data Exchange (ETDEWEB)

    Giri, C.C.; Sharma, D.K. [Indian Institute of Technology, New Delhi (India). Centre for Energy Studies

    2004-07-01

    The washability characteristics of original Indian coals and solvent-extracted residual coals were studied by the float and sink technique. The following conclusions were drawn on the basis of the present study. Anthracene oil-extracted residual coals have lower percentage of reactions in the specific gravity range of 1.4 to 1.6 than the original coals, which indicates that the mineral matter is disassociated from the organic mass, and the anthracene oil-extracted residual coal is more suitable for washing than the original coal. The floatability behaviour of coal increases during NMP (N-methyl-2-pyrrolidone) extraction. This indicates that coal changes its washability character during NMP extractions. As during NMP extraction the surface area of coal increases by creating fissures in the matrix, the chemical leaching technique would be more suitable to remove the mineral matter in the residual coals. 12 refs., 3 figs., 2 tabs.

  15. Reservoir Characterization, Production Characteristics, and Research Needs for Fluvial/Alluvial Reservoirs in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Cole, E.L.; Fowler, M.L.; Jackson, S.R.; Madden, M.P.; Raw-Schatzinger, V.; Salamy, S.P.; Sarathi, P.; Young, M.A.

    1999-04-28

    The Department of Energy's (DOE's) Oil Recovery Field Demonstration Program was initiated in 1992 to maximize the economically and environmentally sound recovery of oil from known domestic reservoirs and to preserve access to this resource. Cost-shared field demonstration projects are being initiated in geology defined reservoir classes which have been prioritized by their potential for incremental recovery and their risk of abandonment. This document defines the characteristics of the fifth geological reservoir class in the series, fluvial/alluvial reservoirs. The reservoirs of Class 5 include deposits of alluvial fans, braided streams, and meandering streams. Deposit morphologies vary as a complex function of climate and tectonics and are characterized by a high degree of heterogeneity to fluid flow as a result of extreme variations in water energy as the deposits formed.

  16. The mineral matter characteristics of some Chinese coal

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X. [China University of Mining and Technology (China). Dept. of Coal Preparation and Utilization

    1994-12-01

    The mineral matter has been separated from 18 coal samples with a low temperature ashes and analyzed by means of X-ray diffraction method. Based on the results of chemical analysis of the coal ash, with reference to the standard composition of minerals, the content of various mineral phases in the coal ash has been determined. Furthermore, this paper summarizes the mineral matter characteristics of the coal samples and discusses the relationship between the composition of mineral matter in coal and its depositional environment.

  17. Use of black oil simulator for coal bed methane reservoir model

    Energy Technology Data Exchange (ETDEWEB)

    Sonwa, R.; Enachescu, C.; Rohs, S. [Golder Associates GmbH, Celle (Germany)

    2013-08-01

    This paper starts from the work done by Seidle et al. (1990) and other authors on the topic of coal degasification and develops a more accurate representative naturally fractured CBM-reservoir by using a Discrete Fracture Network modeling approach. For this issue we firstly calibrate the reservoir simulator tNAVIGATOR by showing his ability to reproduce the work done by Seidle et al. and secondly generate a DFN model using FracMan in accordance with the distribution and orientation of the cleats. tNavigator was then used to simulate multiphase flow through the DFN- Model. (orig.)

  18. Thermo-hydrodynamical modelling of a flooded deep mine reservoir - Case of the Lorraine Coal Basin

    International Nuclear Information System (INIS)

    Reichart, Guillaume

    2015-01-01

    Since 2006, cessation of dewatering in Lorraine Coal Basin (France) led to the flooding of abandoned mines, resulting in a new hydrodynamic balance in the area. Recent researches concerning geothermal exploitation of flooded reservoirs raised new questions, which we propose to answer. Our work aimed to understand the thermos-hydrodynamic behaviour of mine water in a flooding or flooded system. Firstly, we synthesized the geographical, geological and hydrogeological contexts of the Lorraine Coal Basin, and we chose a specific area for our studies. Secondly, temperature and electric conductivity log profiles were measured in old pits of the Lorraine Coal Basin, giving a better understanding of the water behaviour at a deep mine shaft scale. We were able to build a thermos-hydrodynamic model and simulate water behaviour at this scale. Flow regime stability is also studied. Thirdly, a hydrodynamic spatialized meshed model was realized to study the hydrodynamic behaviour of a mine reservoir as a whole. Observed water-table rise was correctly reproduced: moreover, the model can be used in a predictive way after the flooding. Several tools were tested, improved or developed to ease the study of flooded reservoirs, as three-dimensional up-scaling of hydraulic conductivities and a coupled spatialized meshed model with a pipe network. (author) [fr

  19. Variations in pore characteristics in high volatile bituminous coals: Implications for coal bed gas content

    Science.gov (United States)

    Mastalerz, Maria; Drobniak, A.; Strapoc, D.; Solano-Acosta, W.; Rupp, J.

    2008-01-01

    The Seelyville Coal Member of the Linton Formation (Pennsylvanian) in Indiana was studied to: 1) understand variations in pore characteristics within a coal seam at a single location and compare these variations with changes occurring between the same coal at different locations, 2) elaborate on the influence of mineral-matter and maceral composition on mesopore and micropore characteristics, and 3) discuss implications of these variations for coal bed gas content. The coal is high volatile bituminous rank with R0 ranging from 0.57% to 0.60%. BET specific surface areas (determined by nitrogen adsorption) of the coals samples studied range from 1.8 to 22.9??m2/g, BJH adsorption mesopore volumes from 0.0041 to 0.0339??cm3/g, and micropore volumes (determined by carbon dioxide adsorption) from 0.0315 to 0.0540??cm3/g. The coals that had the largest specific surface areas and largest mesopore volumes occur at the shallowest depths, whereas the smallest values for these two parameters occur in the deepest coals. Micropore volumes, in contrast, are not depth-dependent. In the coal samples examined for this study, mineral-matter content influenced both specific surface area as well as mesopore and micropore volumes. It is especially clear in the case of micropores, where an increase in mineral-matter content parallels the decrease of micropore volume of the coal. No obvious relationships were observed between the total vitrinite content and pore characteristics but, after splitting vitrinite into individual macerals, we see that collotelinite influences both meso- and micropore volume positively, whereas collodetrinite contributes to the reduction of mesopore and micropore volumes. There are large variations in gas content within a single coal at a single location. Because of this variability, the entire thickness of the coal must be desorbed in order to determine gas content reliably and to accurately calculate the level of gas saturation. ?? 2008 Elsevier B.V. All

  20. A New Tree-Type Fracturing Method for Stimulating Coal Seam Gas Reservoirs

    Directory of Open Access Journals (Sweden)

    Qian Li

    2017-09-01

    Full Text Available Hydraulic fracturing is used widely to stimulate coalbed methane production in coal mines. However, some factors associated with conventional hydraulic fracturing, such as the simple morphology of the fractures it generates and inhomogeneous stress relief, limit its scope of application in coal mines. These problems mean that gas extraction efficiency is low. Conventional fracturing may leave hidden pockets of gas, which will be safety hazards for subsequent coal mining operations. Based on a new drilling technique applicable to drilling boreholes in coal seams, this paper proposes a tree-type fracturing technique for stimulating reservoir volumes. Tree-type fracturing simulation experiments using a large-scale triaxial testing apparatus were conducted in the laboratory. In contrast to the single hole drilled for conventional hydraulic fracturing, the tree-type sub-boreholes induce radial and tangential fractures that form complex fracture networks. These fracture networks can eliminate the “blank area” that may host dangerous gas pockets. Gas seepage in tree-type fractures was analyzed, and gas seepage tests after tree-type fracturing showed that permeability was greatly enhanced. The equipment developed for tree-type fracturing was tested in the Fengchun underground coal mine in China. After implementing tree-type fracturing, the gas extraction rate was around 2.3 times greater than that for traditional fracturing, and the extraction rate remained high for a long time during a 30-day test. This shortened the gas drainage time and improved gas extraction efficiency.

  1. Environmental characteristics of clean coal technologies

    International Nuclear Information System (INIS)

    Bossart, S.J.

    1992-01-01

    The Department of Energy's (DOE) Clean Coal Technology (CCT) Program is aimed at demonstrating the commercial readiness of advanced coal-based technologies. A major goal of the CCT program is to introduce into the US energy marketplace those coal-based power generation technologies that have superior economic and environmental performance over the current suite of commercial coal-based power generation technologies. The commercialization of CCTs will provide the electric utility industry with technology options for replacing aging power plants and meeting future growth in electricity demand. This paper discusses the environmental advantages of two CCTs used for electric power generation: pressurized fluidized-bed combustion (PFBC) and integrated gasification combined-cycle (IGCC). These CCTs are suitable for repowering existing power plants or for grassroots construction. Due to their high efficiency and advanced environmental control systems, they emit less sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), particulate matter, and carbon dioxide (CO 2 ) than a state-of-the-art, pulverized coal power plant with flue gas desulfurization (PC/FGD)

  2. Characteristic parameters of the coal briquetting process

    International Nuclear Information System (INIS)

    Davkova, Katica

    1998-01-01

    The complete knowledge about the energetic sources in our country - Republic of Macedonia, point to the fact that coals are the most attractive and highly productive, still keeping the leadership position. However, the process of lignite exploitation causes their degradation and formation of large amount of fine fractions. The industrial valorization of these fractions is the most actual problem that could be solved only through production of made-up enriched fuels of wide spectrum of application. Thus, briquetting formation, with or without use of binds, is a process of mechanical or combined modification of coal fine fractions. At the same time, this is a possible procedure of solid fuels enrichment. Lignite from the Macedonian coal deposits 'Suvodol', 'Priskupshtina' and 'Brik-Berovo' is analyzed, in order to examine the possibilities of its briquetting. The results show that the 'Suvodol' lignite satisfy the quality requirements given with the MKS B H1.031 standard as well as the 'Brik-Berovo' lignite

  3. Floatability characteristics: A case study with three typical Indian prime coking coals

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, D.; Singh, A.K.; Banerjee, P.K. [Tata Steel Ltd., Jamshedpur (India). Division for Research & Development

    2008-07-01

    Three types of prime coking coals (coals A, B, and C) from Jharia coalfield, India, were investigated for the variations in their floatability characteristics. Among the three coals studied, coal A showed the least floatability. However, its floatability improved to some extent at higher dosages of collector and frother. Other two types of coal, i.e., coals B and C, showed almost similar flotation performance, which was much better as compared to coal A. The studies revealed that coal showed the least floatability characteristics, primarily due to the least concentration of vitrinite and liptinite content and a high percentage of inertinite and mineral matters in the coal. Also, the lower type of vitrinite (V7-V9) was present in the coal in greater proportion as compared to the other two coals and the proportion of ultra fines (-0.053mm) in coal A was higher as compared to the other two coals.

  4. Stress distribution characteristics in the vicinity of coal seam floor

    Science.gov (United States)

    Cui, Zimo; Chanda, Emmanuel; Zhao, Jingli; Wang, Zhihe

    2018-01-01

    Although longwall top-coal caving (LTCC) has been a popular, more productive and cost-effective method in recent years, roadway floor heave and rock bursts frequently appear when exploiting such coal seams with large dip angle. This paper proposes addressing this problem by adopting three-dimensional roadway layout of stagger arrangement (3-D RLSA). In this study, the first step was to analyse the stress distribution characteristics in the vicinity of coal seam floor based on the stress slip line field theory. In the second step, numerical calculation using FLAC3D was conducted. Finally, an evaluation of the 3-D RLSA for solving this particular issue was given. Results indicate that for this particular mine the proposed 3-D RLSA results in 24% increase in the coal recovery ratio and a modest reduction in excavation and maintenance costs compared to the conventional LTCC method.

  5. Development of the first coal seam gas exploration program in Indonesia: Reservoir properties of the Muaraenim Formation, south Sumatra

    Energy Technology Data Exchange (ETDEWEB)

    Sosrowidjojo, I.B. [R and D Centre for Oil and Gas Technology, LEMIGAS, Jakarta (Indonesia); Saghafi, A. [CSIRO Energy Technology, P O Box 330, Newcastle, NSW, 2300 (Australia)

    2009-09-01

    The Late Miocene Muaraenim Formation in southern Sumatra contains thick coal sequences, mostly of low rank ranging from lignite to sub-bituminous, and it is believed that these thick low rank coals are the most prospective for the production of coal seam gas (CSG), otherwise known as coalbed methane (CBM), in Indonesia. As part of a major CSG exploration project, gas exploration drilling operations are being undertaken in Rambutan Gasfields in the Muaraenim Formation to characterize the CSG potential of the coals. The first stage of the project, which is described here, was designed to examine the gas reservoir properties with a focus on coal gas storage capacity and compositional properties. Some five CSG exploration boreholes were drilled in the Rambutan Gasfield, south of Palembang. The exploration boreholes were drilled to depths of {proportional_to} 1000 m into the Muaraenim Formation. Five major coal seams were intersected by these holes between the depths of 450 and 1000 m. The petrography of coal samples collected from these seams showed that they are vitrinite rich, with vitrinite contents of more than 75% (on a mineral and moisture free basis). Gas contents of up to 5.8 m{sup 3}/t were measured for the coal samples. The gas desorbed from coal samples contain mainly methane (CH{sub 4}) ranging from 80 to 93% and carbon dioxide (CO{sub 2}) ranging from 6 to 19%. The composition of the gas released into the production borehole/well is, however, much richer in CH{sub 4} with about 94 to 98% CH{sub 4} and less than 5% CO{sub 2}. The initial results of drilling and reservoir characterization studies indicate suitable gas recovery parameters for three of the five coal seams with a total thickness of more than 30 m. (author)

  6. Characteristics of volcanic reservoirs and distribution rules of effective reservoirs in the Changling fault depression, Songliao Basin

    Directory of Open Access Journals (Sweden)

    Pujun Wang

    2015-11-01

    Full Text Available In the Songliao Basin, volcanic oil and gas reservoirs are important exploration domains. Based on drilling, logging, and 3D seismic (1495 km2 data, 546 sets of measured physical properties and gas testing productivity of 66 wells in the Changling fault depression, Songliao Basin, eruptive cycles and sub-lithofacies were distinguished after lithologic correction of the 19,384 m volcanic well intervals, so that a quantitative analysis was conducted on the relation between the eruptive cycles, lithologies and lithofacies and the distribution of effective reservoirs. After the relationship was established between lithologies, lithofacies & cycles and reservoir physical properties & oil and gas bearing situations, an analysis was conducted on the characteristics of volcanic reservoirs and the distribution rules of effective reservoirs. It is indicated that 10 eruptive cycles of 3 sections are totally developed in this area, and the effective reservoirs are mainly distributed at the top cycles of eruptive sequences, with those of the 1st and 3rd Members of Yingcheng Formation presenting the best reservoir properties. In this area, there are mainly 11 types of volcanic rocks, among which rhyolite, rhyolitic tuff, rhyolitic tuffo lava and rhyolitic volcanic breccia are the dominant lithologies of effective reservoirs. In the target area are mainly developed 4 volcanic lithofacies (11 sub-lithofacies, among which upper sub-lithofacies of effusive facies and thermal clastic sub-lithofacies of explosion lithofacies are predominant in effective reservoirs. There is an obvious corresponding relationship between the physical properties of volcanic reservoirs and the development degree of effective reservoirs. The distribution of effective reservoirs is controlled by reservoir physical properties, and the formation of effective reservoirs is influenced more by porosity than by permeability. It is concluded that deep volcanic gas exploration presents a good

  7. Reservoir characteristics and control factors of Carboniferous volcanic gas reservoirs in the Dixi area of Junggar Basin, China

    Directory of Open Access Journals (Sweden)

    Ji'an Shi

    2017-02-01

    Full Text Available Field outcrop observation, drilling core description, thin-section analysis, SEM analysis, and geochemistry, indicate that Dixi area of Carboniferous volcanic rock gas reservoir belongs to the volcanic rock oil reservoir of the authigenic gas reservoir. The source rocks make contact with volcanic rock reservoir directly or by fault, and having the characteristics of near source accumulation. The volcanic rock reservoir rocks mainly consist of acidic rhyolite and dacite, intermediate andesite, basic basalt and volcanic breccia: (1 Acidic rhyolite and dacite reservoirs are developed in the middle-lower part of the structure, have suffered strong denudation effect, and the secondary pores have formed in the weathering and tectonic burial stages, but primary pores are not developed within the early diagenesis stage. Average porosity is only at 8%, and the maximum porosity is at 13.5%, with oil and gas accumulation showing poor performance. (2 Intermediate andesite and basic basalt reservoirs are mainly distributed near the crater, which resembles the size of and suggests a volcanic eruption. Primary pores are formed in the early diagenetic stage, secondary pores developed in weathering and erosion transformation stage, and secondary fractures formed in the tectonic burial stage. The average porosity is at 9.2%, and the maximum porosity is at 21.9%: it is of the high-quality reservoir types in Dixi area. (3 The volcanic breccia reservoir has the same diagenetic features with sedimentary rocks, but also has the same mineral composition with volcanic rock; rigid components can keep the primary porosity without being affected by compaction during the burial process. At the same time, the brittleness of volcanic breccia reservoir makes it easily fracture under the stress; internal fracture was developmental. Volcanic breccia developed in the structural high part and suffered a long-term leaching effect. The original pore-fracture combination also made

  8. Quantum chemistry calculation and experimental study on coal ash fusion characteristics of coal blend

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yushuang; Zhang Zhong-xiao; Wu Xiao-jiang; Li Jie; Guang Rong-qing; Yan Bo [University of Shanghai for Science and Technology, Shanghai (China). Department of Power Engineering

    2009-07-01

    The coal ash fusion characteristics of high fusibility coal blending with two low fusibility coals respectively were studied. The data were analyzed using quantum chemistry methods and experiment from micro-and macro-molecular structures. The results show that Ca{sup 2+}, as the electron acceptor, easily enters into the lattice of mullite, causing a transition from mullite to anorthite. Mullite is much more stable than anorthite. Ca{sup 2+} of anorthite occupies the larger cavities with the (SiO{sub 4}){sup 4-} tetrahedral or (AlO{sub 4}){sup 5-} tetrahedral rings respectively. Ca atom linked O weakens Si-O bond, leading ash fusion point to reduce effectively. The chemistry, reactivity sites and bond-formation characteristics of minerals can well explain the reaction mechanism refractory minerals and flux ash melting process at high temperature. The results of experiment are agreed with the theory analysis by using ternary phase diagrams and quantitative calculation. 27 refs., 9 figs., 3 tabs.

  9. Geological Factors and Reservoir Properties Affecting the Gas Content of Coal Seams in the Gujiao Area, Northwest Qinshui Basin, China

    Directory of Open Access Journals (Sweden)

    Zhuo Zou

    2018-04-01

    Full Text Available Coalbed methane (CBM well drilling and logging data together with geological data were adopted to provide insights into controlling mechanism of gas content in major coal seams and establish gas accumulation models in the Gujiao area, Northwest Qinshui Basin, China. Gas content of targeted coals is various in the Gujiao area with their burial depth ranging from 295 to 859 m. Highly variable gas content of coals should be derived from the differences among tectonism, magmatism, hydrodynamism, and sedimentation. Gas content preserved in the Gujiao area is divided into two parts by the geological structure. Gas tends to accumulate in the groundwater stagnant zone with a total dissolved solids (TDS value of 1300–1700 ppm due to water pressure in the Gujiao area. Reservoir properties including moisture content, minerals, and pore structure also significantly result in gas content variability. Subsequently, the gray correlation statistic method was adopted to determine the most important factors controlling gas content. Coal metamorphism and geological structure had marked control on gas content for the targeted coals. Finally, the favorable CBM exploitation areas were comprehensively evaluated in the Gujiao area. The results showed that the most favorable CBM exploitation areas were in the mid-south part of the Gujiao area (Block I.

  10. Influence of high-energy impact on the physical and technical characteristics of coal fuels

    Science.gov (United States)

    Mal'tsev, L. I.; Belogurova, T. P.; Kravchenko, I. V.

    2017-08-01

    Currently, in the world's large-scale coal-fired power industry, the combustion of pulverized coal is the most widely spread technology of combusting the coals. In recent years, the micropulverization technology for preparation and combustion of the coal has been developed in this field. As applied to the small-scale power industry, the method of combusting the coal in the form of a coal-water slurry has been explored for years. Fine coal powders are produced and used in the pulverized-coal gasification. Therefore, the coal preparation methods that involve high-dispersion disintegration of coals attract the greatest interest. The article deals with the problems of high-energy impact on the coal during the preparation of pulverized-coal fuels and coal-water slurries, in particular, during the milling of the coal in ball drum mills and the subsequent regrinding in disintegrators or the cavitation treatment of the coal-water slurries. The investigations were conducted using samples of anthracite and lignite from Belovskii open-pit mine (Kuznetsk Basin). It is shown that both the disintegration and the cavitation treatment are efficient methods for controlling the fuel characteristics. Both methods allow increasing the degree of dispersion of the coal. The content of the small-sized particles reground by cavitation considerably exceeds the similar figure obtained using the disintegrator. The specific surface area of the coal is increased by both cavitation and disintegration with the cavitation treatment producing a considerably greater effect. Being subjected to the cavitation treatment, most coal particles assume the form of a split characterized by the thermodynamically nonequilibrium state. Under external action, in particular, of temperature, the morphological structure of such pulverized materials changes faster and, consequently, the combustion of the treated coal should occur more efficiently. The obtained results are explained from the physical point of view.

  11. Low temperature oxidation and spontaneous combustion characteristics of upgraded low rank coal

    Energy Technology Data Exchange (ETDEWEB)

    Choi, H.K.; Kim, S.D.; Yoo, J.H.; Chun, D.H.; Rhim, Y.J.; Lee, S.H. [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2013-07-01

    The low temperature oxidation and spontaneous combustion characteristics of dried coal produced from low rank coal using the upgraded brown coal (UBC) process were investigated. To this end, proximate properties, crossing-point temperature (CPT), and isothermal oxidation characteristics of the coal were analyzed. The isothermal oxidation characteristics were estimated by considering the formation rates of CO and CO{sub 2} at low temperatures. The upgraded low rank coal had higher heating values than the raw coal. It also had less susceptibility to low temperature oxidation and spontaneous combustion. This seemed to result from the coating of the asphalt on the surface of the coal, which suppressed the active functional groups from reacting with oxygen in the air. The increasing upgrading pressure negatively affected the low temperature oxidation and spontaneous combustion.

  12. Effects of microwave irradiation treatment on physicochemical characteristics of Chinese low-rank coals

    International Nuclear Information System (INIS)

    Ge, Lichao; Zhang, Yanwei; Wang, Zhihua; Zhou, Junhu; Cen, Kefa

    2013-01-01

    Highlights: • Typical Chinese lignites with various ranks are upgraded through microwave. • The pore distribution extends to micropore region, BET area and volume increase. • FTIR show the change of microstructure and improvement in coal rank after upgrading. • Upgraded coals exhibit weak combustion similar to Da Tong bituminous coal. • More evident effects are obtained for raw brown coal with relative lower rank. - Abstract: This study investigates the effects of microwave irradiation treatment on coal composition, pore structure, coal rank, function groups, and combustion characteristics of typical Chinese low-rank coals. Results showed that the upgrading process (microwave irradiation treatment) significantly reduced the coals’ inherent moisture, and increased their calorific value and fixed carbon content. It was also found that the upgrading process generated micropores and increased pore volume and surface area of the coals. Results on the oxygen/carbon ratio parameter indicated that the low-rank coals were upgraded to high-rank coals after the upgrading process, which is in agreement with the findings from Fourier transform infrared spectroscopy. Unstable components in the coal were converted into stable components during the upgrading process. Thermo-gravimetric analysis showed that the combustion processes of upgraded coals were delayed toward the high-temperature region, the ignition and burnout temperatures increased, and the comprehensive combustion parameter decreased. Compared with raw brown coals, the upgraded coals exhibited weak combustion characteristics similar to bituminous coal. The changes in physicochemical characteristics became more notable when processing temperature increased from 130 °C to 160 °C or the rank of raw brown coal was lower. Microwave irradiation treatment could be considered as an effective dewatering and upgrading process

  13. Thermal surface characteristics of coal fires 1 results of in-situ measurements

    Science.gov (United States)

    Zhang, Jianzhong; Kuenzer, Claudia

    2007-12-01

    Natural underground coal fires are fires in coal seams occurring subsurface. The fires are ignited through a process named spontaneous combustion, which occurs based on a natural reaction but is usually triggered through human interaction. Coal mining activities expose coal to the air. This leads to the exothermal oxidation of the carbon in the coal with the air's oxygen to CO 2 and - under certain circumstances - to spontaneous combustion. Coal fires occur in many countries world wide - however, currently the Chinese coal mining industry faces the biggest problems with coal fires. Coal fires destroy the valuable resource coal and furthermore lead to many environmental degradation phenomena such as the deterioration of surrounding vegetation, land subsidence and the emission of toxic gasses (CO, N 2O). They additionally contribute to the emission of green house relevant gasses such as CO 2 and CH 4 to the atmosphere. In this paper we present thermal characteristics of coal fires as measured in-situ during a field campaign to the Wuda coal fire area in south-central Inner Mongolia, China. Thermal characteristics include temperature anomaly measurements at the surface, spatial surface temperature profiles of fire areas and unaffected background areas, diurnal temperature profiles, and temperature measurements inside of coal fire induced cracks in the overlying bedrock. For all the measurements the effects of uneven solar heating through influences of slope and aspect are considered. Our findings show that coal fires result in strong or subtle thermal surface anomalies. Especially the latter can easily be influenced by heating of the surrounding background material through solar influences. Temperature variation of background rocks with different albedo, slope, aspect or vegetation cover can substantially influence the detectability of thermal anomalies. In the worst case coal fire related thermal anomalies can be completely masked by solar patterns during the daytime

  14. Influence of the microwave irradiation dewatering on the combustion characteristics of Chinese brown coals

    Science.gov (United States)

    Ge, Lichao; Feng, Hongcui; Xu, Chang; Zhang, Yanwei; Wang, Zhihua

    2018-02-01

    This study investigates the influence of microwave irradiation on coal composition, pore structure, coal rank, and combustion characteristics of typical brown coals in China. Results show that the upgrading process significantly decreased the inherent moisture, and increased calorific value and fixed carbon content. After upgrading, pore distribution extended to micropore region, oxygen functional groups were reduced and destroyed, and the apparent aromaticity increased suggesting an improvement in the coal rank. Based on thermogravimetric analysis, the combustion processes of upgraded coals were delayed toward the high temperature region, and the temperatures of ignition, peak and burnout increased. Based on the average combustion rate and comprehensive combustion parameter, the upgraded coals performed better compared with raw brown coals and a high rank coal. In ignition and burnout segments, the activation energy increased but exhibited a decrease in the combustion stage.

  15. SOME CHARACTERISTICS OF THE "KONGORA" - TOMISLAVGRAD COAL FIELD (WEST HERZEGOVINA

    Directory of Open Access Journals (Sweden)

    Stanislav Živković

    1997-12-01

    Full Text Available According to it's energy potential »Kongora« coal field is very important source of energy. Coal strech, spreading and laying and proportion between coal and barren give good presumption for a rentabile surface exploitation. The coal analyses, specially analysis of sulphur content showed, that content of harm component on the update technology level is in permissible limits, and exploitation in thermal power plants will not destroy environment (the paper is published in Croatian.

  16. Determining water reservoir characteristics with global elevation data

    NARCIS (Netherlands)

    van Bemmelen, C. W T; Mann, M.; de Ridder, M.P.; Rutten, M.M.; van de Giesen, N.C.

    2016-01-01

    Quantification of human impact on water, sediment, and nutrient fluxes at the global scale demands characterization of reservoirs with an accuracy that is presently unavailable. This letter presents a new method, based on virtual dam placement, to make accurate estimations of area-volume

  17. Pyrolysis characteristics and kinetics of low rank coals by distributed activation energy model

    International Nuclear Information System (INIS)

    Song, Huijuan; Liu, Guangrui; Wu, Jinhu

    2016-01-01

    Highlights: • Types of carbon in coal structure were investigated by curve-fitted "1"3C NMR spectra. • The work related pyrolysis characteristics and kinetics with coal structure. • Pyrolysis kinetics of low rank coals were studied by DAEM with Miura integral method. • DAEM could supply accurate extrapolations under relatively higher heating rates. - Abstract: The work was conducted to investigate pyrolysis characteristics and kinetics of low rank coals relating with coal structure by thermogravimetric analysis (TGA), the distributed activation energy model (DAEM) and solid-state "1"3C Nuclear Magnetic Resonance (NMR). Four low rank coals selected from different mines in China were studied in the paper. TGA was carried out with a non-isothermal temperature program in N_2 at the heating rate of 5, 10, 20 and 30 °C/min to estimate pyrolysis processes of coal samples. The results showed that corresponding characteristic temperatures and the maximum mass loss rates increased as heating rate increased. Pyrolysis kinetics parameters were investigated by the DAEM using Miura integral method. The DAEM was accurate verified by the good fit between the experimental and calculated curves of conversion degree x at the selected heating rates and relatively higher heating rates. The average activation energy was 331 kJ/mol (coal NM), 298 kJ/mol (coal NX), 302 kJ/mol (coal HLJ) and 196 kJ/mol (coal SD), respectively. The curve-fitting analysis of "1"3C NMR spectra was performed to characterize chemical structures of low rank coals. The results showed that various types of carbon functional groups with different relative contents existed in coal structure. The work indicated that pyrolysis characteristics and kinetics of low rank coals were closely associated with their chemical structures.

  18. Combustion Characteristics Of Agricultural Waste-Coal Char Blends

    International Nuclear Information System (INIS)

    Akpabio, I. O; Danbature W

    2002-01-01

    Shortage of petroleum products, depletion of huge forest reserves for fuel purposes with its attendant erosion problems and other environmental considerations have necessitated investigations into other sources of fuel. In this wise. a set of seven types of briquettes were prepared from agricultural wastes such as rice husk, maize husk and saw-dust and blends of carbonized coal char. Strong and well-formed briquettes with good combustion characteristics were obtained. The results obtained from water boiling tests show that 2 litres of water could be boiled just under 23 minutes. Moisture contents and strengths of these briquettes were also determined and are discussed. The results show that wastes could be converted into useful fuel

  19. Influence of the hydrothermal dewatering on the combustion characteristics of Chinese low-rank coals

    International Nuclear Information System (INIS)

    Ge, Lichao; Zhang, Yanwei; Xu, Chang; Wang, Zhihua; Zhou, Junhu; Cen, Kefa

    2015-01-01

    This study investigates the influence of hydrothermal dewatering performed at different temperatures on the combustion characteristics of Chinese low-rank coals with different coalification maturities. It was found that the upgrading process significantly decreased the inherent moisture and oxygen content, increased the calorific value and fixed carbon content, and promoted the damage of the hydrophilic oxygen functional groups. The results of oxygen/carbon atomic ratio indicated that the upgrading process converted the low-rank coals near to high-rank coals which can also be gained using the Fourier transform infrared spectroscopy. The thermogravimetric analysis showed that the combustion processes of upgraded coals were delayed toward the high temperature region, and the upgraded coals had higher ignition and burnout temperature. On the other hand, based on the higher average combustion rate and comprehensive combustion parameter, the upgraded coals performed better compared with raw brown coals and the Da Tong bituminous coal. In ignition segment, the activation energy increased after treatment but decreased in the combustion stage. The changes in coal compositions, microstructure, rank, and combustion characteristics were more notable as the temperature in hydrothermal dewatering increased from 250 to 300 °C or coals of lower ranks were used. - Highlights: • Typical Chinese lignites with various ranks are upgraded by hydrothermal dewatering. • Upgraded coals exhibit chemical compositions comparable with that of bituminous coal. • FTIR show the change of microstructure and improvement in coal rank after upgrading. • Upgraded coals exhibit difficulty in ignition but combust easily. • More evident effects are obtained for raw brown coal with relative lower rank.

  20. Size Effect on Acoustic Emission Characteristics of Coal-Rock Damage Evolution

    Directory of Open Access Journals (Sweden)

    Zhijie Wen

    2017-01-01

    Full Text Available Coal-gas outburst, rock burst, and other mine dynamic disasters are closely related to the instability and failure of coal-rock. Coal-rock is the assemblies of mineral particles of varying sizes and shapes bonded together by cementing materials. The damage and rupture process of coal-rock is accompanied by acoustic emission (AE, which can be used as an effective means to monitor and predict the instability of coal-rock body. In this manuscript, considering the size effect of coal-rock, the influence of different height to diameter ratio on the acoustic emission characteristics of coal-rock damage evolution was discussed by microparticle flow PFC2D software platform. The results show that coal-rock size influences the uniaxial compressive strength, peak strain, and elastic modulus of itself; the size effect has little effect on the acoustic emission law of coal-rock damage and the effects of the size of coal-rock samples on acoustic emission characteristics are mainly reflected in three aspects: the triggering time of acoustic emission, the strain range of strong acoustic emission, and the intensity of acoustic emission; the damage evolution of coal-rock specimen can be divided into 4 stages: initial damage, stable development, accelerated development, and damage.

  1. Characteristics of Malaysian coals with their pyrolysis and gasification behaviour

    International Nuclear Information System (INIS)

    Nor Fadzilah Othman; Mohd Hariffin Bosrooh; Kamsani Abdul Majid

    2010-01-01

    This study was conducted since comprehensive study on the gasification behaviour of Malaysian coals is still lacking. Coals were characterised using heating value determination, proximate analysis, ultimate analysis and ash analysis. Pyrolysis process was investigated using thermogravimetric analyser. While, atmospheric bubbling fluidized bed gasifier was used to investigate the gasification behaviour. Three Malaysian coals, Merit Pila, Mukah Balingian, Silantek; and Australian coal, Hunter Valley coals were used in this study. Thermal degradation of four coal samples were performed, which involved weight loss profile and derivative thermogravimetric (DTG) curves. The kinetic parameters, such as maximum reactivity value, R max , Activation Energy, E a and Arrhenius constant, ln R o for each coal were determined using Arrhenius Equation. Merit Pila coal shows the highest maximum reactivity among other Malaysian coals. E a is the highest for Merit Pila coal (166.81kJmol -1 ) followed with Mukah Balingian (101.15 kJmol -1 ), Hunter Valley (96.45 kJmol -1 ) and Silantek (75.23 kJmol -1 ) coals. This finding indicates direct correlation of lower rank coal with higher E a . Merit Pila coal was studied in detail using atmospheric bubbling fluidized bed gasifier. Different variables such as equivalence ratio (ER) and gasifying agents were used. The highest H 2 proportion (38.3 mol.%) in the producer gas was reached at 715 degree Celsius and ER=0.277 where the maximization of LHV pg (5.56 MJ/Nm 3 ) was also detected. ER and addition of steam had shown significant contributions to the producer gas compositions and LHV pg . (author)

  2. Deposit Mariovo geological characteristics coal quality and quantity

    International Nuclear Information System (INIS)

    Andreevski, Borche

    2008-01-01

    Evaluation of the actual situation with energy resources, in a global scale, shows negative trends, which is result from the numerous complex factors influences. Special influence over these trends has increased requirement and consumption of the fossil fuels, driven by the intensive technological development and unplanned long-term exploitation, which causes huge reduction of the available fossil fuels deposits and significant price oscillations. Additional contribution to this tendency has the fact that potential fossil fuels reserves are controlled from limited number of owners, which allows them to have global geo-strategic control over the energy resources, world politics and other types of influences. In such conditions underdevelopment countries will feel the biggest consequences and they will be forced to provide(conditionally, if there is an energy surplus at the market) and to save considerable financial resources for satisfying their needs. Maximal usage of country's own possessed energy raw material bases the only way out from this situation and it is also used by the countries which are at he greatest development level then ours. If we want to incorporate these reserves into the energetic strategy and energy balances they must be exactly defined and determined. According to the presented approach, paper has aim to make synthesis of previous investigations, through argumentation of geological specifics and quantitative-qualitative characteristics of deposit Mariovo coal given in the available documentation, and also has intention to point out its respectable characteristics. (Author)

  3. Deposit Mariovo geological characteristics coal quality and quantity

    International Nuclear Information System (INIS)

    Andreevski, Borche

    2007-01-01

    Evaluation of the actual situation with energy resources, in a global scale, shows negative trends, which is result from the numerous complex factors influences. Special influence over these trends has increased requirement and consumption of the fossil fuels, driven by the intensive technological development and unplanned long-term exploitation, which causes huge reduction of the available fossil fuels deposits and significant price oscillations. Additional contribution to this tendency has the fact that potential fossil fuels reserves are controlled from limited number of owners, which allows them to have global geo-strategic control over the energy resources, world politics and other types of influences. In such conditions underdevelopment countries will feel the biggest consequences and they will be forced to provide(conditionally, if there is an energy surplus at the market) and to save considerable financial resources for satisfying their needs. Maximal usage of country's own possessed energy raw material bases the only way out from this situation and it is also used by the countries which are at he greatest development level then ours. If we want to incorporate these reserves into the energetic strategy and energy balances they must be exactly defined and determined. According to the presented approach, paper has aim to make synthesis of previous investigations, through argumentation of geological specifics and quantitative-qualitative characteristics of deposit Mariovo coal given in the available documentation, and also has intention to point out its respectable characteristics. (Author)

  4. Geological and production characteristics of strandplain/barrier island reservoirs in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Cole, E.L.; Fowler, M.; Jackson, S.; Madden, M.P.; Reeves, T.K.; Salamy, S.P.; Young, M.A.

    1994-12-01

    The Department of Energy`s (DOE`s) primary mission in the oil research program is to maximize the economically and environmentally sound recovery of oil from domestic reservoirs and to preserve access to this resource. The Oil Recovery Field Demonstration Program supports DOE`s mission through cost-shared demonstrations of improved Oil Recovery (IOR) processes and reservoir characterization methods. In the past 3 years, the DOE has issued Program Opportunity Notices (PONs) seeking cost-shared proposals for the three highest priority, geologically defined reservoir classes. The classes have been prioritized based on resource size and risk of abandonment. This document defines the geologic, reservoir, and production characteristics of the fourth reservoir class, strandplain/barrier islands. Knowledge of the geological factors and processes that control formation and preservation of reservoir deposits, external and internal reservoir heterogeneities, reservoir characterization methodology, and IOR process application can be used to increase production of the remaining oil-in-place (IOR) in Class 4 reservoirs. Knowledge of heterogeneities that inhibit or block fluid flow is particularly critical. Using the TORIS database of 330 of the largest strandplain/barrier island reservoirs and its predictive and economic models, the recovery potential which could result from future application of IOR technologies to Class 4 reservoirs was estimated to be between 1.0 and 4.3 billion barrels, depending on oil price and the level of technology advancement. The analysis indicated that this potential could be realized through (1) infill drilling alone and in combination with polymer flooding and profile modification, (2) chemical flooding (sufactant), and (3) thermal processes. Most of this future potential is in Texas, Oklahoma, and the Rocky Mountain region. Approximately two-thirds of the potentially recoverable resource is at risk of abandonment by the year 2000.

  5. Spontaneous ignition characteristics of coal in a large-scale furnace: An experimental and numerical investigation

    International Nuclear Information System (INIS)

    Wen, Hu; Yu, Zhijin; Deng, Jun; Zhai, Xiaowei

    2017-01-01

    Highlights: • Three coal spontaneous combustion coupled models based on various flow equations were constructed and compared. • The airflow behavior in loose coal should be defined as a Brinkman flow. • The self-heating of coal in a large-scale reactor was numerically reappeared. • The effect of heat dissipated conditions on temperature profiles of broken coal was presented. - Abstract: A comprehensive understanding of the spontaneous combustion characteristics of coal in various surroundings is necessary for developing reliable test platform and predictive models. In this study, the characteristics of oxidation and self-heating combining various gas flow equations in loose coal were investigated separately and used to simulate the experimental procedure of spontaneous combustion. The main focus was to investigate the effect of thermal boundary on temperature profiles as well as spontaneous combustion period. The results showed that the numerical approach was validated by comparison with the test data. Furthermore, the model based upon Brinkman equation showed a higher accuracy, which indicated that airflow behavior influences the balances of coal oxidation and heat dissipation, thus impacts the temperature profiles of loose coal. The areas of high temperature zones would be evidently expanded and the spontaneous ignition time would be significantly accelerated if the thermal exchange between the coal and its surroundings decreased. Our results, especially for the field of engineering, have substantial effects for grasping and controlling coal spontaneous combustion disaster.

  6. Effect of coal blending on the leaching characteristics of arsenic and selenium in fly ash from fluidized bed coal combustion

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, F.; Yamada, N.; Sato, A.; Ninomiya, Yoshihiko [Chubu Univ., Aichi (Japan). Dept. of Applied Chemistry; Zhang, L. [Monash Univ., Clayton, VIC (Australia). Dept. of Chemical Engineering

    2013-07-01

    The capture ability of fly ash to arsenic (As) and selenium (Se) was investigated through the combustion of two single bituminous coals A and B and their mixture (blending ratio of 1:1, wt/wt) in a lab-scale fluidized bed reactor. The leaching characteristics of As and Se in corresponding fly ash were also conducted according to Japanese Industrial Standard (JIS). Speciation of As and Se during fly ash leaching test were predicted from the perspective of thermodynamic equilibrium. The results indicate that, combustion of coal B, containing abundant calcium, possesses a higher capture ability of As and Se than that of coal A through possible chemical reaction between As/Se with CaO. Leaching behavior of As and Se from fly ash is strongly dependent on the pH of the leachate. Free calcium in fly ash generates an alkaline leachate during leaching test and subsequently reduces As and Se leaching, which cause the leaching ratio of As and Se in fly ash derived from the combustion of coal B was much lower, relative to that in coal A. Combustion of blending coal promotes the overall capture ability of the fly ash to As/Se and reduces their leaching from fly ash through the synergy of free CaO between this two kind of fly ash.

  7. Limnological characteristics and trophic state of a newly created site: the Pareja Limno-reservoir

    Science.gov (United States)

    Molina-Navarro, E.; Martínez-Pérez, S.; Sastre-Merlín, A.

    2012-04-01

    The creation of dams in the riverine zone of large reservoirs is an innovative action whose primary goal is to generate water bodies that ensure a stable level of water there. We have termed these bodies of water "limno-reservoirs" because their water level becomes constant and independent of the fluctuations occurring in the main reservoir. In addition, limno-reservoirs represent environmental initiatives with corrective and/or compensatory effects. Pareja Limno-reservoir, located near the left side of Entrepeñas Reservoir (Guadalajara province, central Spain), is one of the first initiatives of this type in Spain. We are investigating the hydrology, limnology, microbiology, siltation risk and other aspects of this site. This research has a special interest since the building of limno-reservoirs is rising in Spain. To acquire knowledge about their behavior may be helpful for further constructions. In fact, every new reservoir building project usually includes a limno-reservoir. Moreover, there are many initiatives related with the construction of this kind of hydraulic infrastructures in the reservoirs under exploitation. This work focuses on the limnological study of the Pareja Limno-reservoir. To conduct this research, twelve seasonal sample collections at two sampling points (the dam and inflow zones) have been made in Pareja Limno-reservoir, from spring 2008 to winter 2011. The primary goal of this study is to describe the limnological characteristics of the limno-reservoir. Special interest is placed in the study of the trophic state through different indicators (nutrients, transparency, phytoplankton and zooplankton populations), as the European Water Framework Directive objective is to achieve a "good ecological status" in every aquatic ecosystem by 2015. The results of the study show that the Pareja Limno-reservoir follows a warm monomictic water stratification pattern. Water was slightly alkaline and conductivity values were mostly over 1000 μS cm-1 due

  8. Coal

    International Nuclear Information System (INIS)

    Teissie, J.; Bourgogne, D. de; Bautin, F.

    2001-12-01

    Coal world production represents 3.5 billions of tons, plus 900 millions of tons of lignite. 50% of coal is used for power generation, 16% by steel making industry, 5% by cement plants, and 29% for space heating and by other industries like carbo-chemistry. Coal reserves are enormous, about 1000 billions of tons (i.e. 250 years of consumption with the present day rate) but their exploitation will be in competition with less costly and less polluting energy sources. This documents treats of all aspects of coal: origin, composition, calorific value, classification, resources, reserves, production, international trade, sectoral consumption, cost, retail price, safety aspects of coal mining, environmental impacts (solid and gaseous effluents), different technologies of coal-fired power plants and their relative efficiency, alternative solutions for the recovery of coal energy (fuel cells, liquefaction). (J.S.)

  9. New Zealand coal characteristics in the global scene

    Energy Technology Data Exchange (ETDEWEB)

    Gillard, G.R.; Moore, T.A. [CRL Energy Research and Testing, Christchurch (New Zealand)

    1999-03-01

    The properties unique to New Zealand coals are highlighted by comparing them to other coal types from throughout the world. This allows them to be ranked for specific users overseas, maximising the return for the producer. 9 refs., 8 figs., 2 tabs.

  10. Ignition characteristics of coal blends in an entrained flow furnace

    Energy Technology Data Exchange (ETDEWEB)

    J. Faundez; B. Arias; F. Rubiera; A. Arenillas; X. Garcia; A.L. Gordon; J.J. Pis [Universidad de Concepcion, Concepcion (Chile)

    2007-09-15

    Ignition tests were carried out on blends of three coals of different rank - subbituminous, high volatile and low volatile bituminous - in two entrained flow reactors. The ignition temperatures were determined from the gas evolution profiles (CO, CO{sub 2}, NO, O{sub 2}), while the mechanism of ignition was elucidated from these profiles and corroborated by high-speed video recording. Under the experimental conditions of high carbon loading, clear interactive effects were observed for all the blends. Ignition of the lower rank coals (subbituminous, high volatile bituminous) enhanced the ignition of the higher rank coal (low volatile bituminous) in the blends. The ignition temperatures of the blends of the low rank coals (subbituminous-high volatile bituminous) were additive. However, for the rest of the blends the ignition temperatures were always closer to the lower rank coal in the blend. 21 refs., 8 figs.

  11. NOx emissions and combustibility characteristics of coal blends

    Energy Technology Data Exchange (ETDEWEB)

    Rubiera, F.; Arenillas, A.; Arias, B.; Pis, J.J. [CSIC, Instituto Nacional del Carbon, Oviedo (Spain). Dept. of Energy and Environment

    2001-07-01

    In this work, a series of coals with different origin and rank were blended and several aspects of the resultant blends were studied. This included determination of the grindability of individual coals and blends by means of the Hardgrove Grindability Index (HGI), and temperature programmed combustion test, which were carried out in a thermogravimetric analyser (TG) coupled to a quadruple mass spectrometer (MS) for evolved gas analysis. Special attention was paid to the combustibility parameters and the NO emissions during blends combustion. It was found that while some coal blends present interaction between the individual coals, others do not. This behaviour was assumed to be due to the differences in coal structure and functional groups composition. 18 refs., 11 figs., 2 tabs.

  12. Deformation Failure Characteristics of Coal Body and Mining Induced Stress Evolution Law

    Directory of Open Access Journals (Sweden)

    Zhijie Wen

    2014-01-01

    Full Text Available The results of the interaction between coal failure and mining pressure field evolution during mining are presented. Not only the mechanical model of stope and its relative structure division, but also the failure and behavior characteristic of coal body under different mining stages are built and demonstrated. Namely, the breaking arch and stress arch which influence the mining area are quantified calculated. A systematic method of stress field distribution is worked out. All this indicates that the pore distribution of coal body with different compressed volume has fractal character; it appears to be the linear relationship between propagation range of internal stress field and compressed volume of coal body and nonlinear relationship between the range of outburst coal mass and the number of pores which is influenced by mining pressure. The results provide theory reference for the research on the range of mining-induced stress and broken coal wall.

  13. Preliminary reservoir model of enhanced coalbed methane (ECBM) in a subbituminous coal seam, Huntly Coalfield, New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Zarrouk, Sadiq J. [Department of Engineering Science, University of Auckland, Private Bag 92019, Auckland (New Zealand); Moore, Tim A. [Solid Energy New Zealand Ltd, PO Box. 1303, Christchurch (New Zealand)]|[Department of Geological Sciences, University of Canterbury, Christchurch (New Zealand)

    2009-01-07

    The Huntly coalfield has significant coal deposits that contain biogenically-sourced methane. The coals are subbituminous in rank and Eocene in age and have been previously characterised with relatively low to moderate measured gas (CH{sub 4}) contents (2-4 m{sup 3}/ton). The CO{sub 2} holding capacity is relatively high (18.0 m{sup 3}/ton) compared with that of CH{sub 4} (2.6 m{sup 3}/ton) and N{sub 2} (0.7 m{sup 3}/ton) at the same pressure (4 MPa; all as received basis). The geothermal gradient is also quite high at 55 C/km. A study has been conducted which simulates enhancement of methane recovery (ECBM) from these deposits using a new version of the TOUGH2 (version 2) reservoir simulator (ECBM-TOUGH2) that can handle non-isothermal, multi-phase flows of mixtures of water, CH{sub 4}, CO{sub 2} and N{sub 2}. The initial phase of the simulation is CH{sub 4} production for the first 5 years of the field history. The model indicates that methane production can be significantly improved (from less than 80% recovery to nearly 90%) through injection of CO{sub 2}. However, although an increase in the rate of CO{sub 2} injection increases the amount of CO{sub 2} sequestered, the methane recovery (because of earlier breakthrough with increasing injection rate) decreases. Modeling of pure N{sub 2} injection produced little enhanced CH{sub 4} production. The injection of a hypothetical flue gas mixture (CO{sub 2} and N{sub 2}) also produced little increase in CH{sub 4} production. This is related to the low adsorption capacity of the Huntly coal to N{sub 2} which results in almost instantaneous breakthrough into the production well. (author)

  14. Sediment pollution characteristics and in situ control in a deep drinking water reservoir.

    Science.gov (United States)

    Zhou, Zizhen; Huang, Tinglin; Li, Yang; Ma, Weixing; Zhou, Shilei; Long, Shenghai

    2017-02-01

    Sediment pollution characteristics, in situ sediment release potential, and in situ inhibition of sediment release were investigated in a drinking water reservoir. Results showed that organic carbon (OC), total nitrogen (TN), and total phosphorus (TP) in sediments increased from the reservoir mouth to the main reservoir. Fraction analysis indicated that nitrogen in ion exchangeable form and NaOH-extractable P (Fe/Al-P) accounted for 43% and 26% of TN and TP in sediments of the main reservoir. The Risk Assessment Code for metal elements showed that Fe and Mn posed high to very high risk. The results of the in situ reactor experiment in the main reservoir showed the same trends as those observed in the natural state of the reservoir in 2011 and 2012; the maximum concentrations of total OC, TN, TP, Fe, and Mn reached 4.42mg/L, 3.33mg/L, 0.22mg/L, 2.56mg/L, and 0.61mg/L, respectively. An in situ sediment release inhibition technology, the water-lifting aerator, was utilized in the reservoir. The results of operating the water-lifting aerator indicated that sediment release was successfully inhibited and that OC, TN, TP, Fe, and Mn in surface sediment could be reduced by 13.25%, 15.23%, 14.10%, 5.32%, and 3.94%, respectively. Copyright © 2016. Published by Elsevier B.V.

  15. Coal geopolitics

    International Nuclear Information System (INIS)

    Giraud, P.N.; Suissa, A.; Coiffard, J.; Cretin, D.

    1991-01-01

    This book divided into seven chapters, describes coal economic cycle. Chapter one: coals definition; the principle characteristics and properties (origin, calorific power, international classification...) Chapter two: the international coal cycle: coal mining, exploration, coal reserves estimation, coal handling coal industry and environmental impacts. Chapter three: the world coal reserves. Chapter four: the consumptions, productions and trade. Chapter five: the international coal market (exporting mining companies; importing companies; distributors and spot market operators) chapter six: the international coal trade chapter seven: the coal price formation. 234 refs.; 94 figs. and tabs [fr

  16. Hydrocarbon accumulation characteristics and enrichment laws of multi-layered reservoirs in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Guang Yang

    2017-03-01

    Full Text Available The Sichuan Basin represents the earliest area where natural gas is explored, developed and comprehensively utilized in China. After over 50 years of oil and gas exploration, oil and gas reservoirs have been discovered in 24 gas-dominant layers in this basin. For the purpose of predicting natural gas exploration direction and target of each layer in the Sichuan Basin, the sedimentary characteristics of marine and continental strata in this basin were summarized and the forms of multi-cycled tectonic movement and their controlling effect on sedimentation, diagenesis and hydrocarbon accumulation were analyzed. Based on the analysis, the following characteristics were identified. First, the Sichuan Basin has experienced the transformation from marine sedimentation to continental sedimentation since the Sinian with the former being dominant. Second, multiple source–reservoir assemblages are formed based on multi-rhythmed deposition, and multi-layered reservoir hydrocarbon accumulation characteristics are vertically presented. And third, multi-cycled tectonic movement appears in many forms and has a significant controlling effect on sedimentation, diagenesis and hydrocarbon accumulation. Then, oil and gas reservoir characteristics and enrichment laws were investigated. It is indicated that the Sichuan Basin is characterized by coexistence of conventional and unconventional oil and gas reservoirs, multi-layered reservoir hydrocarbon supply, multiple reservoir types, multiple trap types, multi-staged hydrocarbon accumulation and multiple hydrocarbon accumulation models. Besides, its natural gas enrichment is affected by hydrocarbon source intensity, large paleo-uplift, favorable sedimentary facies belt, sedimentary–structural discontinuity plane and structural fracture development. Finally, the natural gas exploration and research targets of each layer in the Sichuan Basin were predicted according to the basic petroleum geologic conditions

  17. Chaotic characteristic of electromagnetic radiation time series of coal or rock under different scales

    Energy Technology Data Exchange (ETDEWEB)

    Zhen-Tang Liu; En-Lai Zhao; En-Yuan Wang; Jing Wang [China University of Mining and Technology, Xuzhou (China). School of Safety Engineering

    2009-02-15

    Based on chaos theory, the chaotic characteristics of electromagnetic radiation time series of coal or rock under different loads was studied. The results show that the correlation of electromagnetic radiation time series of small-scale coal or rock and coal mine converges to a stable saturation value, which shows that these electromagnetic radiation time series have chaos characteristics. When there is danger of coal seam burst, the value of the saturation correlation dimension D{sub 2} of the electromagnetic radiation time series is bigger and it changes greatly; when there is no danger, its value is smaller and changes smoothly. The change of saturation correlation of electromagnetic radiation time series can be used to forecast coal or rock dynamic disasters. 11 refs., 4 figs.

  18. Process to improve combustion and coalescing characteristics of coal pellets

    Energy Technology Data Exchange (ETDEWEB)

    Ban, T.E.; Marlowe, W.H.

    1980-10-23

    Baking types of coal, which occur mainly in the Midwestern States of the USA, tend to form solid layers when heated to remove tar. In order to prevent this, it is proposed to pulverize the coal, to form small pellets and to coat these pellets. A suitable coating material mentioned here is sodium carbonate. Variants of the coating process are given. The coated pellets are heated.

  19. Study on infrasonic characteristics of coal samples in failure process under uniaxial loading

    Directory of Open Access Journals (Sweden)

    Bing Jia

    Full Text Available To study the precursory failure infrasonic characteristics of coal samples, coal rock stress loading system and infrasonic wave acquisition system were adopted, and infrasonic tests in uniaxial loading process were made for the coal samples in the studied area. Wavelet filtering, fast Fourier transform, and relative infrasonic energy methods were used to analyze the characteristics of the infrasonic waves in the loading process, including time domain characteristics, and relative energy. The analysis results demonstrated that the frequencies of the infrasonic signals in the loading process mainly distribute within 5–10 Hz, which are significantly different from noise signals. The changes of the infrasonic signals show clear periodic characters in time domain. Meanwhile, the relative energy changes of the infrasonic wave also show periodic characters, which are divided into two stages by the yield limit of coal samples, and are clear and easy to be recognized, so that they can be used as the precursory characteristics for recognizing coal sample failures. Moreover, the infrasonic waves generated by coal samples have low frequency and low attenuation, which can be collected without coupling and transmitted in long distance. This study provides an important support for the further in-situ prediction of coal rock failures. Keywords: Infrasound, Relative energy, Time-frequency analysis, Failure prediction, Identification feature

  20. Effect of Crusher Type and Crusher Discharge Setting On Washability Characteristics of Coal

    Science.gov (United States)

    Ahila, P.; Battacharya, S.

    2018-02-01

    Natural resources have been serving the life of many civilizations, among these coals are of prime importance. Coal is the most important and abundant fossil fuel in India. It accounts for 55% of the country’s energy need. Coal will continue as the mainstay fuel for power generation. Previous researches has been made about the coal feed size and coal type had great influence on the crushing performance of the same jaw crusher and amount of fines generated from a particular coal depends not only upon coal friability but also on crusher type. Therefore, it necessitates crushing and grinding the coal for downstream process. In this paper the effect of crusher type and crusher discharge setting on washability characteristics of same crushed non-coking coal has been studied. Thus four different crushers were investigated at variable parameters like discharge settings, different capacities and feed openings. The experimental work conducted for all crushers with same feed size and HGI (Hardgrove Grindability Index). Based on the investigation the results indicate that the four crushers which has been involved for the experimental work shows that the variation in not only the product size distribution and also reduction ratio. Maximum breakage has been occurred at coarsest size fraction of irrespective of crusher type and discharge setting.

  1. Waterberg coal characteristics and SO2 minimum emissions standards in South African power plants.

    Science.gov (United States)

    Makgato, Stanford S; Chirwa, Evans M Nkhalambayausi

    2017-10-01

    Key characteristics of coal samples from the supply stock to the newly commissioned South African National Power Utility's (Eskom's) Medupi Power Station - which receives its supply coal from the Waterberg coalfield in Lephalale (Limpopo Province, South Africa) - were evaluated. Conventional coal characterisation such as proximate and ultimate analysis as well as determination of sulphur forms in coal samples were carried out following the ASTM and ISO standards. Coal was classified as medium sulphur coal when the sulphur content was detected in the range 1.15-1.49 wt.% with pyritic sulphur (≥0.51 wt.%) and organic sulphur (≥0.49 wt.%) accounted for the bulk of the total sulphur in coal. Maceral analyses of coal showed that vitrinite was the dominant maceral (up to 51.8 vol.%), whereas inertinite, liptinite, reactive semifusinite and visible minerals occurred in proportions of 22.6 vol.%, 2.9 vol.%, 5.3 vol.% and 17.5 vol.%, respectively. Theoretical calculations were developed and used to predict the resultant SO 2 emissions from the combustion of the Waterberg coal in a typical power plant. The sulphur content requirements to comply with the minimum emissions standards of 3500 mg/Nm 3 and 500 mg/Nm 3 were found to be ≤1.37 wt.% and ≤0.20 wt.%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. THE OHIO RIVER VALLEY CO2 STORAGE PROJECT - PRELIMINARY ASSESSMENT OF DEEP SALINE RESERVOIRS AND COAL SEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Michael J. Mudd; Howard Johnson; Charles Christopher; T.S. Ramakrishnan, Ph.D.

    2003-08-01

    This report describes the geologic setting for the Deep Saline Reservoirs and Coal Seams in the Ohio River Valley CO{sub 2} Storage Project area. The object of the current project is to site and design a CO{sub 2} injection facility. A location near New Haven, WV, has been selected for the project. To assess geologic storage reservoirs at the site, regional and site-specific geology were reviewed. Geologic reports, deep well logs, hydraulic tests, and geologic maps were reviewed for the area. Only one well within 25 miles of the site penetrates the deeper sedimentary rocks, so there is a large amount of uncertainty regarding the deep geology at the site. New Haven is located along the Ohio River on the border of West Virginia and Ohio. Topography in the area is flat in the river valley but rugged away from the Ohio River floodplain. The Ohio River Valley incises 50-100 ft into bedrock in the area. The area of interest lies within the Appalachian Plateau, on the western edge of the Appalachian Mountain chain. Within the Appalachian Basin, sedimentary rocks are 3,000 to 20,000 ft deep and slope toward the southeast. The rock formations consist of alternating layers of shale, limestone, dolomite, and sandstone overlying dense metamorphic continental shield rocks. The Rome Trough is the major structural feature in the area, and there may be some faults associated with the trough in the Ohio-West Virginia Hinge Zone. The area has a low earthquake hazard with few historical earthquakes. Target injection reservoirs include the basal sandstone/Lower Maryville and the Rose Run Sandstone. The basal sandstone is an informal name for sandstones that overlie metamorphic shield rock. Regional geology indicates that the unit is at a depth of approximately 9,100 ft below the surface at the project site and associated with the Maryville Formation. Overall thickness appears to be 50-100 ft. The Rose Run Sandstone is another potential reservoir. The unit is located approximately 1

  3. Respiratory and reproductive characteristics of eastern mosquitofish (Gambusia holbrooki) inhabiting a coal ash settling basin

    Energy Technology Data Exchange (ETDEWEB)

    Staub, B.P.; Hopkins, W.A.; Novak, J.; Congdon, J.D. [University of Georgia, Aiken, SC (United States). Savannah River Ecology Lab.

    2004-01-01

    Coal fly ash and effluent from coal ash settling basins negatively affects metabolism and reproduction in a variety of organisms, including a number of fish species. Some species, most notably the eastern mosquitofish (Gambusia holbrooki), are known to maintain viable populations in areas contaminated by coal ash. While eastern mosquitofish are present in these systems, their degree of tolerance to coal ash has not been investigated using sublethal metrics of exposure. It is possible that eastern mosquitofish persist in habitats affected by coal ash, but experience significant costs such as changes in metabolism and fecundity. Thus, we investigated the effects of coal ash on standard metabolic rate and reproduction of eastern mosquitofish inhabiting a coal-ash contaminated settling basin. Standard metabolic rates of mosquitofish from the ash contaminated site and a reference site were not significantly different. Despite elevated contaminant concentrations in ash basin females (selenium, arsenic, copper, and cadmium) and their offspring (selenium), brood sizes and offspring viability did not differ between clutches collected from ash basin and reference site females. Our data provide further evidence of the high degree of tolerance of eastern mosquitofish to exposure to aquatic coal ash disposal generated by power plants. However, the basis for such tolerance to ash remains unclear. Further investigations are required to determine whether such tolerance is a result of species-specific characteristics or population characteristics due to local adaptation.

  4. Secondary biogenic coal seam gas reservoirs in New Zealand: A preliminary assessment of gas contents

    Energy Technology Data Exchange (ETDEWEB)

    Butland, Carol I. [Department of Geological Sciences, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Moore, Tim A. [Department of Geological Sciences, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Solid Energy NZ Ltd., P.O. Box 1303, Christchurch (New Zealand)

    2008-10-02

    Four coal cores, one from the Huntly (Eocene), two from the Ohai (Cretaceous) and one from the Greymouth (Cretaceous) coalfields, were sampled and analysed in terms of gas content and coal properties. The coals vary in rank from subbituminous B-A (Huntly) to subbituminous C-A (Ohai), and high volatile A bituminous (Greymouth). Average gas contents were 1.60 m{sup 3}/t (s 0.2) in the Huntly core, 4.80 m{sup 3}/t (s = 0.8) in the Ohai cores, and 2.39 m{sup 3}/t (s = 0.8) in the Greymouth core. The Ohai core not only contained more gas but also had the highest saturation (75%) compared with the Huntly (33%) and Greymouth (45%) cores. Carbon isotopes indicate that the Ohai gas is more mature, containing higher {delta}{sup 13}C isotopes values than either the Huntly or Greymouth gas samples. This may indicate that the gas was derived from a mixed biogenic and thermogenic source. The Huntly and Greymouth gases appear to be derived solely from a secondary biogenic (by CO{sub 2} reduction) source. Although the data set is limited, preliminary analysis indicates that ash yield is the dominant control on gas volume in all samples where the ash yield was above 10%. Below 10%, the amount of gas variation is unrelated to ash yield. Although organic content has some influence on gas volume, associations are basin and/or rank dependent. In the Huntly core total gas content and structured vitrinite increase together. Although this relationship does not appear for the other core data for the Ohai SC3 core, lost gas and fusinite are associated whereas gelovitrinite (unstructured vitrinite) correlates positively with residual gas for the Greymouth data. (author)

  5. An insight into the mechanism and evolution of shale reservoir characteristics with over-high maturity

    Directory of Open Access Journals (Sweden)

    Xinjing Li

    2016-10-01

    Full Text Available Over-high maturity is one of the most vital characteristics of marine organic-rich shale reservoirs from the Lower Paleozoic in the south part of China. The organic matter (OM in shale gas reservoirs almost went through the entire thermal evolution. During this wide span, a great amount of hydrocarbon was available and numerous pores were observed within the OM including kerogen and solid bitumen/pyrobitumen. These nanopores in solid bitumen/pyrobitumen can be identified using SEM. The imaging can be dissected and understood better based on the sequence of diagenesis and hydrocarbon charge with the shape of OM and pores. In terms of the maturity process showed by the various typical cases, the main effects of the relationship between the reservoir porosity and organic carbon abundance are interpreted as follows: the change and mechanism of reservoirs properties due to thermal evolution are explored, such as gas carbon isotope from partial to complete rollover zone, wettability alteration from water-wet to oil-wet and then water-wet pore surface again, electrical resistivity reversal from the increasing to decreasing stage, and nonlinearity fluctuation of rock elasticity anisotropy. These indicate a possible evolution pathway for shale gas reservoirs from the Lower Paleozoic in the southern China, as well as the general transformation processes between different shale reservoirs in thermal stages.

  6. Determination of Japanese buyer valuation of metallurgical coal characteristics by hedonic modeling

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, R.J. [Griffith University, Brisbane, Qld. (Australia). Graduate School of Management

    2001-09-01

    Considerable efforts have been devoted by econometric researchers to understanding Japanese steel mill (JSM) metallurgical coal valuation policies, and whether such policies disadvantage coal exporters. Much of this research has employed the hedonic regression modeling technique of Rosen and examines the significance of coal quality in establishing market price. This article discusses shortcomings in some such modeling studies, and presents results of additional hedonic modeling to buttress findings of previous work suggesting that cross-cultural bargaining factors rather than coal quality explain lower prices for Australian coals in Japanese market settlements. Policy changes that might be effective in ameliorating bilateral market distortions arising from oligopsony characteristics exhibited in JSM contract settlements are then explored. 29 refs., 2 figs., 2 tabs.

  7. The mechanical properties and hydration characteristics of cement pastes containing added-calcium coal gangue

    Energy Technology Data Exchange (ETDEWEB)

    Dongxu Li; Xuyan Song [Nanjing University of Technology, Nanjing (China). College of Material Science and Engineering

    2008-04-15

    The mechanical properties of several kinds of coal gangue calcined with limestone were researched so as to find the optimum way of calcinations with limestone. The microstructure and property of hydration process of cement pastes containing added-calcium coal gangue were analyzed by means of scanning electron microscope (SEM) and the method of mercury in trusion poremeasurement. When the proper amounst of gypsum and fluorite were taken as mineralizers in the course of calcinations of added-calcium coal gangue, the activity of coal gangue can be effectively improved. The results of mechanical property and structural characteristics such as hydration, hydration products and microstructure etc. of cement pastes containing added-calcium coal gangue are consistent.

  8. Coal characteristics from 'Priskupshtina' deposit and technological parameters for briquetting (Macedonia)

    International Nuclear Information System (INIS)

    Damjanovski, Dragan

    1998-01-01

    The use of small class coal as well as the lack of formed fuel needed for the industry and for the consumer goods has been a long lasting problem, and a challenge for the researchers of the Republic of Macedonia. For that purpose, all-inclusive analysis of the quality of the coals in Macedonia, their reserves and technical characteristics, as well as analysis of the petrographic structure were made. Classification of the deposits and the research for the possibility of making briquettes was done, too. Laboratory investigations in the coal deposit 'Priskupshtina' were carried out. The analysis of the coal briquetting show that the expected results in coordination with the required standards were not obtained. Spatially the results from the coal calorific value, its hardness and atmospheric resistance. Standard methods were used for the researches without connective means and the achieved results were mutually correlated. Technical-economic verification is necessary in the further process. (Author)

  9. NO emission characteristics of superfine pulverized coal combustion in the O2/CO2 atmosphere

    International Nuclear Information System (INIS)

    Liu, Jiaxun; Gao, Shan; Jiang, Xiumin; Shen, Jun; Zhang, Hai

    2014-01-01

    Highlights: • Superfine pulverized coal combustion in O 2 /CO 2 atmosphere is a new promising technology. • NO emissions of superfine pulverized coal combustion in O 2 /CO 2 mixture were focused. • Coal particle sizes have significant effects on NO emissions in O 2 /CO 2 combustion. - Abstract: The combination of O 2 /CO 2 combustion and superfine pulverized coal combustion technology can make full use of their respective merits, and solve certain inherent disadvantages of each technology. The technology of superfine pulverized coal combustion in the O 2 /CO 2 atmosphere is easy and feasible to be retrofitted with few reconstructions on the existing devices. It will become a useful and promising method in the future. In this paper, a one-dimensional drop-tube furnace system was adopted to study the NO emission characteristics of superfine pulverized coal combustion in the O 2 /CO 2 atmosphere. The effects of coal particle size, coal quality, furnace temperature, stoichiometric ratio, etc. were analyzed. It is important to note that coal particle sizes have significant influence on NO emissions in the O 2 /CO 2 combustion. For the homogeneous NO reduction, smaller coal particles can inhibit the homogeneous NO formations under fuel-rich combustion conditions, while it becomes disadvantageous for fuel-lean combustion. However, under any conditions, heterogeneous reduction is always more significant for smaller coal particle sizes, which have smoother pore surfaces and simpler pore structures. The results from this fundamental research will provide technical support for better understanding and developing this new combustion process

  10. Similar simulation study on the characteristics of the electric potential response to coal mining

    Science.gov (United States)

    Niu, Yue; Li, Zhonghui; Kong, Biao; Wang, Enyuan; Lou, Quan; Qiu, Liming; Kong, Xiangguo; Wang, Jiali; Dong, Mingfu; Li, Baolin

    2018-02-01

    An electric potential (EP) can be generated during the failure process of coal and rock. In this article, a similar physical model of coal rock was built and the characteristics of the EP responding to the process of coal mining were studied. The results showed that, at the early mining stage, the structure of coal rock strata were stable in the simulation model, the support stress of overlying coal rock strata was low and the maximum subsidence was little, while the EP change was less. With the advancement of the working face, the support stress of the overlying coal rock strata in the mined-out area changed dramatically, the maximum subsidence increased constantly, the deformation and destruction were aggravated, and cracks expanded continuously. Meanwhile, the EP response was significant with fluctuation. When significant macro damage appeared in coal rock strata, the EP signal fluctuation was violent. The overlying coal rock strata were influenced by gravity and mining activity. During the mining process, the crack growth and the friction, together with slip between coal and rock particles, resulted in the response of EP. The change in EP was closely related to the damage state and stress distribution of the coal rock strata. EP monitoring has the advantages of accurate reflection and strong anti-interference in the field. Therefore, with further study, an EP monitoring method could be applied for monitoring and early warning of coal and rock dynamic disaster, and risk evaluation in the future. The strength of the EP and its fluctuation degree could serve as the key discrimination indexes.

  11. Applicability of WRF-Lake System in Studying Reservoir-Induced Impacts on Local Climate: Case Study of Two Reservoirs with Contrasting Characteristics

    Science.gov (United States)

    Wang, F.; Zhu, D.; Ni, G.; Sun, T.

    2017-12-01

    Large reservoirs play a key role in regional hydrological cycles as well as in modulating the local climate. The emerging large reservoirs in concomitant with rapid hydropower exploitation in southwestern China warrant better understanding of their impacts on local and regional climates. One of the crucial pathways through which reservoirs impact the climate is lake-atmospheric interaction. Although such interactions have been widely studied with numeric weather prediction (NWP) models, an outstanding limitation across various NWPs resides on the poor thermodynamic representation of lakes. The recent version of Weather Research and Forecasting (WRF) system has been equipped with a one-dimensional lake model to better represent the thermodynamics of large water body and has been shown to enhance the its predication skill in the lake-atmospheric interaction. In this study, we further explore the applicability of the WRF-Lake system in two reservoirs with contrasting characteristics: Miyun Reservoir with an average depth of 30 meters in North China Plain, and Nuozhadu Reservoir with an average depth of 200 meters in the Tibetan Plateau Region. Driven by the high spatiotemporal resolution meteorological forcing data, the WRF-Lake system is used to simulate the water temperature and surface energy budgets of the two reservoirs after the evaluation against temperature observations. The simulated results show the WRF-Lake model can well predict the vertical profile of water temperature in Miyun Reservoir, but underestimates deep water temperature and overestimates surface temperature in the deeper Nuozhadu Reservoir. In addition, sensitivity analysis indicates the poor performance of the WRF-Lake system in Nuozhadu Reservoir could be attributed to the weak vertical mixing in the model, which can be improved by tuning the eddy diffusion coefficient ke . Keywords: reservoir-induced climatic impact; lake-atmospheric interaction; WRF-Lake system; hydropower exploitation

  12. Propagation characteristics of pulverized coal and gas two-phase flow during an outburst.

    Science.gov (United States)

    Zhou, Aitao; Wang, Kai; Fan, Lingpeng; Tao, Bo

    2017-01-01

    Coal and gas outbursts are dynamic failures that can involve the ejection of thousands tons of pulverized coal, as well as considerable volumes of gas, into a limited working space within a short period. The two-phase flow of gas and pulverized coal that occurs during an outburst can lead to fatalities and destroy underground equipment. This article examines the interaction mechanism between pulverized coal and gas flow. Based on the role of gas expansion energy in the development stage of outbursts, a numerical simulation method is proposed for investigating the propagation characteristics of the two-phase flow. This simulation method was verified by a shock tube experiment involving pulverized coal and gas flow. The experimental and simulated results both demonstrate that the instantaneous ejection of pulverized coal and gas flow can form outburst shock waves. These are attenuated along the propagation direction, and the volume fraction of pulverized coal in the two-phase flow has significant influence on attenuation of the outburst shock wave. As a whole, pulverized coal flow has a negative impact on gas flow, which makes a great loss of large amounts of initial energy, blocking the propagation of gas flow. According to comparison of numerical results for different roadway types, the attenuation effect of T-type roadways is best. In the propagation of shock wave, reflection and diffraction of shock wave interact through the complex roadway types.

  13. Southern hemisphere coal characteristics and their impact on plant performance

    Energy Technology Data Exchange (ETDEWEB)

    Chiou, Y Y; Dickson, A J; Lowe, A; Pearson, J M; Pitman, B L; Semark, P M [Taiwan Power Company (Taiwan)

    1992-09-01

    The paper reports performance information of specific utilities fired by coal mined in the Southern Hemisphere. It includes information from Pacific Power Services, Australia, the China Light and Power Company, Hong Kong, the Taiwan Power Company, Taiwan, and the South Africa Electricity Power Company, South Africa. 12 refs., 3 figs., 12 tabs.

  14. Geothermal characteristics of Buntsandstein sandstone reservoir of Alsace

    International Nuclear Information System (INIS)

    Haffen, Sebastien

    2012-01-01

    The Buntsandstein, located in the Upper Rhine Graben, appears to be an easy target for geothermal exploitation, linking sandstone and clay with the regional thermal anomaly. This study aims at characterizing petrophysical characteristics of these sandstones as well as the fracturing affecting them, with the intention of providing a conceptual model of the formation which will act as guide for future exploitation. The sedimentary facies are composed by five petrographical facies (clean sandstones, sandstones with clayey coating, clay matrix sandstones, silicified sandstones and carbonated matrix sandstones) which split with variable proportions and control a part of petrophysical properties measured at matrix scale. The comparison between petrophysical data, macroscopic data from temperature gradient analysis, modelling data and fracturing, allows the building of a Buntsandstein Sandstones fluids circulation conceptual model. This analysis points the role of the damage zone of fault zones for fluids transfer at large scale, but also that of two sedimentary facies: marginal erg and Playa Lake. The analysis of different outcrops shows that the fracturing evolves according to the situation in the sedimentary pile and according to the situation in comparison with major tectonic accidents. (author) [fr

  15. MORPHOMETRIC CHARACTERISTICS OF TROPICAL SHALLOW RESERVOIR USED FOR AQUACULTURE AND AGRICULTURE IN THE MEXICAN PLATEAU

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    Aldama GR

    2013-01-01

    Full Text Available Morphometric characteristics of a tropical shallow reservoir situated in the Southern Mexican Highlands were studied. Seventeen morphometric parameters were measured. Results of the morphometric parameters showed that this reservoir presented a soft and roughness bottom, with an ellipsoid form and a concave depression that allow the mix up of water and sediments, causing turbidity and broken thermal gradients; its slight slopes allowed the colonization of submerged macrophyte and halophyte plants and they improve the incidence of sunlight on water surface increasing evaporation and primary productivity. Tropical shallow reservoirs have fluctuations in area and volume according to the amount of rainfall, the effect of evaporation, the temperature levels, lost of volume due to irrigation, and other causes.

  16. Gasification Characteristics of Coal/Biomass Mixed Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Reginald [Stanford Univ., CA (United States). Mechanical Engineering Dept.

    2014-09-01

    A research project was undertaken that had the overall objective of developing the models needed to accurately predict conversion rates of coal/biomass mixtures to synthesis gas under conditions relevant to a commercially-available coal gasification system configured to co-produce electric power as well as chemicals and liquid fuels. In our efforts to accomplish this goal, experiments were performed in an entrained flow reactor in order to produce coal and biomass chars at high heating rates and temperatures, typical of the heating rates and temperatures fuel particles experience in real systems. Mixed chars derived from coal/biomass mixtures containing up to 50% biomass and the chars of the pure coal and biomass components were subjected to a matrix of reactivity tests in a pressurized thermogravimetric analyzer (TGA) in order to obtain data on mass loss rates as functions of gas temperature, pressure and composition as well as to obtain information on the variations in mass specific surface area during char conversion under kinetically-limited conditions. The experimental data were used as targets when determining the unknown parameters in the chemical reactivity and specific surface area models developed. These parameters included rate coefficients for the reactions in the reaction mechanism, enthalpies of formation and absolute entropies of adsorbed species formed on the carbonaceous surfaces, and pore structure coefficients in the model used to describe how the mass specific surface area of the char varies with conversion. So that the reactivity models can be used at high temperatures when mass transport processes impact char conversion rates, Thiele modulus – effectiveness factor relations were also derived for the reaction mechanisms developed. In addition, the reactivity model and a mode of conversion model were combined in a char-particle gasification model that includes the effects of chemical reaction and diffusion of reactive gases through particle

  17. PBC Triggers in Water Reservoirs, Coal Mining Areas and Waste Disposal Sites: From Newcastle to New York

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    Daniel Smyk

    2010-01-01

    Full Text Available Various environmental factors have been proposed as triggers of primary biliary cirrhosis (PBC, a progressive autoimmune cholestatic liver disease which is characterised by the destruction of the small intrahepatic bile ducts. Support for their pathogenic role in PBC is provided by epidemiological studies reporting familial clustering and clusters of the disease within a given geographical area. The seminal study by Triger reporting that the great majority of PBC cases in the English city of Sheffield drank water from a specific water reservoir, has been followed by studies reporting disease 'hot spots' within a restricted geographic region of the former coal mining area of Newcastle. The New York study reporting an increased risk and significant clustering of PBC cases near toxic federal waste disposal sites has added strength to the notion that environmental factors, possibly in the form of infectious agents or toxic/chemical environmental factors in areas of contaminated land, water or polluted air may play a key role in the development of the disease. This review discusses the findings of reports investigating environmental factors which may contribute to the cause of primary biliary cirrhosis.

  18. Biological characteristics of silver bream (Blicca bjoerkna in commercial fishery in the Kyiv reservoir

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    I. Zakharchenko

    2016-12-01

    Full Text Available Purpose. The determination and analysis of main biological characteristics of silver bream from the point of view of the formation and exploitation of its commercial stock in the Kyiv reservoir. Methodology. The work is based the results of monitoring field studies carried out on the Kyiv reservoir during 2012–2014. Ichthyological materials were collected from standard commercial gill nets with mesh sizes of 30–80 mm, which were set in different habitats and depths of the reservoir. Collection and processing of samples was carried out using conventional ichthyological methods adapted for the Dnieper reservoirs. Findings. According to the data of monitoring gill nets, silver bream population in 2014 was composed of 10 age groups. The majority of their population (70.8% in catches was composed of age-5 to age-7 fish, i.e. the number of modal classes increased due to the right wing of the older age groups. The frequency distribution of silver bream had a shape of a curve with wide, however broken (due to the reduction in age-5 fish peak and gradual decrease. Age-length properties, fatness parameters and condition factor of silver bream in the Kiev reservoir during last years remained on the stable high level indicating on favorable fattening conditions and forming the ichthyomass of this species. At the present time, silver bream of the Kyiv reservoir formed a commercial stock with such qualitative and quantitative characteristics, which allow exploiting it in the mode of traditional commercial harvest and specialized harvest of silver bream concentrations with the use of gill nets with mesh sizes of 50, 60 mm. Originality. We obtained and analyzed the new data on the current state of silver bream (Blіcca bjoerkna in Kyiv reservoir as an important element of commercial fish production. Practical Value. The results of the work allows increasing qualitative and quantitative characteristics of silver bream catches and will be used for the

  19. Petrographic characteristics and depositional environment of Miocene Can coals, Canakkale-Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Guerdal, Guelbin; Bozcu, Mustafa [Canakkale Onsekiz Mart University, Engineering and Architecture Faculty (Turkey)

    2011-01-01

    In this study, petrographic examinations along with proximate, calorific value, ultimate, sulphur form and XRD analyses were performed in order to determine the coal characteristics and the depositional environment of the Miocene Can coals. Seventy coal samples were taken from cores and open pit mines. The investigated Can coals are humic coals and classified as lignite to sub-bituminous coal based on the random huminite reflectance (0.38-0.54% R{sub r}), volatile matter (45.50-62.25 wt.%, daf) and calorific value (3419-6479 kcal/kg, maf). The sulphur content of the Can coals changes from 0.30 up to 12.23 wt.%, and a broad range of ash contents was observed varying between 2.46 wt.% and 41.19 wt.%. Huminite is the most abundant maceral group (74-95 vol.% mmf) consisting of mostly humocollinite (gelinite) which is followed by relatively low liptinite (2-18 vol.% mmf) and inertinite content (2-13 vol.% mmf). In general, major mineral contents of coal samples are clay minerals, quartz, mica, pyrite and feldspar. The Can-Etili lignite basin consists of mainly volcano-clastics, fluviatile and lacustrine clastic sediments and contains only one lignite seam with 17 m average thickness. In order to assess the development of paleo-mires, coal facies diagrams were obtained from maceral composition. According to the Vegetation Index (VI) and Ground Water Index (GWI), the Can coal accumulated in inundated marsh, limnic and swamp environments under a rheotrophic hydrological regime. In general, the facies interpretations are in accordance with the observed sedimentalogical data. (author)

  20. Study on electromagnetic radiation and mechanical characteristics of coal during an SHPB test

    Science.gov (United States)

    Chengwu, Li; Qifei, Wang; Pingyang, Lyu

    2016-06-01

    Dynamic loads provided by a Split Hopkinson pressure bar are applied in the impact failure experiment on coal with an impact velocity of 4.174-17.652 m s-1. The mechanical property characteristics of coal and an electromagnetic radiation signal can be detected and measured during the experiment. The variation of coal stress, strain, incident energy, dissipated energy and other mechanical parameters are analyzed by the unidimensional stress wave theory. It suggests that with an increase of the impact velocity, the mechanical parameters and electromagnetic radiation increased significantly and the dissipated energy of the coal sample has a high discrete growing trend during the failure process of coal impact. Combined with the received energy of the electromagnetic radiation signal, the relationship between these mechanical parameters and electromagnetic radiation during the failure process of coal burst could be analyzed by the grey correlation model. The results show that the descending order of the gray correlation degree between the mechanical characteristics and electromagnetic radiation energy are impact velocity, maximum stress, the average stress, incident energy, the average strain, maximum strain, the average strain rate and dissipation energy. Due to the correlation degree, the impact velocity and incident energy are relatively large, and the main factor affecting the electromagnetic radiation energy of coal is the energy magnitude. While the relationship between extreme stress and the radiation energy change trend is closed, the stress state of coal has a greater impact on electromagnetic radiation than the strain and destruction which can deepen the research of the coal-rock dynamic disaster electromagnetic monitoring technique.

  1. Effect of pore structure on the seepage characteristics of tight sandstone reservoirs: A case study of Upper Jurassic Penglaizhen Fm reservoirs in the western Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Liqiang Sima

    2017-01-01

    Full Text Available Tight sandstone reservoirs are characterized by complex pore structures and strong heterogeneity, and their seepage characteristics are much different from those of conventional sandstone reservoirs. In this paper, the tight sandstone reservoirs of Upper Jurassic Penglaizhen Fm in western Sichuan Basin were analyzed in terms of their pore structures by using the data about physical property, mercury injection and nuclear magnetic resonance (NMR tests. Then, the seepage characteristics and the gas–water two-phase migration mechanisms and distribution of tight sandstone reservoirs with different types of pore structures in the process of hydrocarbon accumulation and development were simulated by combining the relative permeability experiment with the visual microscopic displacement model. It is shown that crotch-like viscous fingering occurs in the process of gas front advancing in reservoirs with different pore structures. The better the pore structure is, the lower the irreducible water saturation is; the higher the gas-phase relative permeability of irreducible water is, the more easily the gas reservoir can be developed. At the late stage of development, the residual gas is sealed in reservoirs in the forms of bypass, cutoff and dead end. In various reservoirs, the interference between gas and water is stronger, so gas and water tends to be produced simultaneously. The sealed gas may reduce the production rate of gas wells significantly, and the existence of water phase may reduce the gas permeability greatly; consequently, the water-bearing low-permeability tight sandstone gas reservoirs reveal serious water production, highly-difficult development and low-recovery percentage at the late stage, which have adverse impacts on the effective production and development of gas wells.

  2. Infrared absorption characteristics of hydroxyl groups in coal tars

    Energy Technology Data Exchange (ETDEWEB)

    Cannon, S A; Chu, C J; Hange, R H; Margrave, J L

    1987-01-01

    Tar evolution was observed over a temperature range of 150-600 C for four coals. Pittsburgh bituminous, Illinois No.6, Rawhide subbituminous, and Texas lignite. Isolation of the evolved tars in a nitrogen matrix at 15 degrees K produced better resolved infrared spectra than those in a coal matrix, thus enhancing structural characterization of the tar molecules. Two distinct hydroxyl functional groups in the tar molecules free of hydrogen bonding were identified for the first time without interference from H/sub 2/O absorptions. These absorptions at 3626.5 cm/sup -1/ have been assigned to phenolic hydroxyls. It is suggested that carboxylic and aliphatic hydroxyl groups do not survive the vaporization process. Tars from Illinois No.6 were found to contain the largest amount of phenolic hydroxyl; Pittsburgh No. 8 tar contains approximately half of that for Illinois No.6 while Rawhide and Texas lignite contain much less phenolic than either of the other coals. 10 references, 6 figures, 1 table.

  3. A location-based multiple point statistics method: modelling the reservoir with non-stationary characteristics

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    Yin Yanshu

    2017-12-01

    Full Text Available In this paper, a location-based multiple point statistics method is developed to model a non-stationary reservoir. The proposed method characterizes the relationship between the sedimentary pattern and the deposit location using the relative central position distance function, which alleviates the requirement that the training image and the simulated grids have the same dimension. The weights in every direction of the distance function can be changed to characterize the reservoir heterogeneity in various directions. The local integral replacements of data events, structured random path, distance tolerance and multi-grid strategy are applied to reproduce the sedimentary patterns and obtain a more realistic result. This method is compared with the traditional Snesim method using a synthesized 3-D training image of Poyang Lake and a reservoir model of Shengli Oilfield in China. The results indicate that the new method can reproduce the non-stationary characteristics better than the traditional method and is more suitable for simulation of delta-front deposits. These results show that the new method is a powerful tool for modelling a reservoir with non-stationary characteristics.

  4. Chemical and physical characteristics of water and sediment in Scofield Reservoir, Carbon County, Utah

    Science.gov (United States)

    Waddell, Kidd M.; Darby, D.W.; Theobald, S.M.

    1985-01-01

    Evaluations based on the nutrient content of the inflow, outflow, water in storage, and the dissolved-oxygen depletion during the summer indicate that the trophic state of Scofield Reservoir is borderline between mesotrophic and eutrophic and may become highly eutrophic unless corrective measures are taken to limit nutrient inflow.Sediment deposition in Scofield Reservoir during 1943-79 is estimated to be 3,000 acre-feet, and has decreased the original storage capacity of the reservoir by 4 percent. The sediment contains some coal, and age dating of those sediments (based on the radioisotope lead-210) indicates that most of the coal was deposited prior to about 1950.Scofield Reservoir is dimictic, with turnovers occurring in the spring and autumn. Water in the reservoir circulates completely to the bottom during turnovers. The concentration of dissolved oxygen decreases with depth except during parts of the turnover periods. Below an altitude of about 7,590 feet, where 20 percent of the water is stored, the concentration of dissolved oxygen was less than 2 milligrams per liter during most of the year. During the summer stratification period, the depletion of dissolved oxygen in the deeper layers is coincident with supersaturated conditions in the shallow layers; this is attributed to plant photosynthesis and bacterial respiration in the reservoir.During October 1,1979-August 31,1980, thedischargeweighted average concentrations of dissolved solids was 195 milligrams per liter in the combined inflow from Fish, Pondtown, and Mud Creeks, and was 175 milligrams per liter in the outflow (and to the Price River). The smaller concentration in the outflow was due primarily to precipitation of calcium carbonate in the reservoir about 80 percent of the decrease can be accounted for through loss as calcium carbonate.The estimated discharge-weighted average concentration of total nitrogen (dissolved plus suspended) in the combined inflow of Fish, Pondtown, and Mud Creeks was 1

  5. Pollution characteristics and source identification of trace metals in riparian soils of Miyun Reservoir, China.

    Science.gov (United States)

    Han, Lanfang; Gao, Bo; Lu, Jin; Zhou, Yang; Xu, Dongyu; Gao, Li; Sun, Ke

    2017-10-01

    The South-to-North Water Diversion Project, one of China's largest water diversion projects, has aroused widespread concerns about its potential ecological impacts, especially the potential release of trace metals from shoreline soils into Miyun Reservoir (MYR). Here, riparian soil samples from three elevations and four types of land use were collected. Soil particle size distributions, contents and chemical fractionations of trace metals and lead (Pb) isotopic compositions were analyzed. Results showed that soil texture was basically similar in four types of land use, being mainly composed of sand, with minor portions of clay and silt, while recreational land contained more abundant chromium (Cr), copper (Cu), zinc (Zn) and cadmium (Cd), suggesting a possible anthropogenic source for this soil pollution. The potential ecological risk assessment revealed considerable contamination of recreational land, with Cd being the predominant contaminant. Chemical fractionations showed that Cu, arsenic (As), Pb and Cd had potential release risks. Additionally, the 206 Pb/ 207 Pb and 208 Pb/ 207 Pb values of soils were similar to those of coal combustion. By combining principal component analysis (PCA) with Pb isotopic results, coal combustion was identified as the major anthropogenic source of Zn, Cr, Cu, Cd and Pb. Moreover, isotope ratios of Pb fell in the scope of aerosols, indicating that atmospheric deposition may be the primary input pathway of anthropogenic Zn, Cr, Cu, Cd and Pb. Therefore, controlling coal combustion should be a priority to reduce effectively the introduction of additional Zn, Cu, Cd, and Pb to the area in the future. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Control of spontaneous combustion of coal in goaf at high geotemperatureby injecting liquid carbon dioxide: inertand cooling characteristics of coal

    Science.gov (United States)

    Liu, Zhenling; Wen, Hu; Yu, Zhijin; Wang, Chao; Ma, Li

    2018-02-01

    The spontaneous combustion of coal in goaf at high geo temperatures is threatening safety production in coalmine. The TG-DSC is employed to study the variation of mass and energy at 4 atmospheres (mixed gases of N2, O2 and CO2) and heating rates (10°C/min) during oxidation of coal samples. The apparent activation energy and pre-exponential factor of coal oxidation decrease rapidly with increasing theCO2 concentration. Furthermore, its reaction rate is slow, its heat released reduces. Based on the conditions of 1301 face in the Longgucoalmine, a three-dimensional geometry model is developed to simulate the distributions stream field and temperature field and the variation characteristics ofCO2 concentration field after injecting liquidCO2. The results indicate that oxygen reached to depths of˜120m in goaf, 100m in the side of inlet air, and 10m in the side of outlet air before injecting liquidCO2. After injecting liquidCO2for 28.8min, the width of oxidation and heat accumulation zone is shortened by 20m, and the distance is 80m in the side of working face and 40˜60m in goafin the direction of dip affected by temperature.

  7. Hydrogeochemical characteristics of groundwater in the coal-bearing aquifer of the Wugou coal mine, northern Anhui Province, China

    Science.gov (United States)

    Chen, Song; Gui, Herong

    2017-07-01

    Major ions, trace elements, and isotope concentrations were measured in 11 representative groundwater samples that were collected from a series of aquifers in the Wugou coal mine, Anhui Province. The geochemical characteristics of the groundwater samples were examined using conventional graphical and multivariate statistical approaches, and the results showed that almost all of the groundwater samples collected from the coal-bearing aquifer were the Na-SO4 type, whereas the samples from the Quaternary and the limestone aquifer were the Ca-SO4 and Na-Cl types, respectively. The groundwater in the study area is not suitable for drinking without treatment because of the higher values of total dissolved solids and other parameters, whereas the lower value of the sodium adsorption ratio indicates that it can be used for irrigation. The total rare earth element concentrations ranged from 0.0398 to 0.1874 mg/L, and had an average of 0.075 mg/L. There were negative cerium and positive europium anomalies in the groundwater. The δD and δ 18O values in groundwater ranged from -9.01 to -8.81 ‰, and from -74.7 to -71.4 ‰, respectively. Meteoric water with variable degrees of evaporation is the main source of the groundwater in the coal-bearing aquifer.

  8. Molecular simulation of methane adsorption characteristics on coal macromolecule

    Science.gov (United States)

    Yang, Zhiyuan; He, Xiaoxiao; Meng, Zhuoyue; Xue, Wenying

    2018-02-01

    In this paper, the molecular model of anthracite named Wender2 was selected to study the adsorption behaviour of single component CH4 and the competitive adsorption of CH4/CO2, CH4/H2O and CH4/N2. The molecular model of anthracite was established by molecular simulation software (Materials Studio 8.0), and Grand Canonical Monte Carlo (GCMC) simulations were carried out to investigate the single and binary component adsorption. The effects of pressure and temperature on the adsorption position, adsorption energy and adsorption capacity were mainly discussed. The results show that for the single component adsorption, the adsorption capacity of CH4 increases rapidly with the pressure ascending, and then tends to be stable after the first step. The low temperature is favourable for the adsorption of CH4, and the high temperature promotes desorption quantity of CH4 from the coal. Adsorbent molecules are preferentially adsorbed on the edge of coal macromolecules. The order of adsorption capacity of CH4/CO2, CH4/H2O and CH4/N2 in the binary component is H2O>CO2>CH4>N2. The change of pressure has little effect on the adsorption capacity of the adsorbent in the competitive adsorption, but it has a great influence on the adsorption capacity of the adsorbent, and there is a positive correlation between them.

  9. Morphological, sediment and soil chemical characteristics of dry tropical shallow reservoirs in the Southern Mexican Highlands

    Directory of Open Access Journals (Sweden)

    José Luis ARREDONDO-FIGUEROA

    2011-02-01

    Full Text Available The morphometry, sediment and soil chemical characteristics of eleven dry tropical shallow reservoirs situated in Southern Mexican Highlands were studied. The reservoirs are located at 1104 to 1183 meters above sea level in a sedimentary area. Seventeen morphometric and eight sediment and soil chemical parameters were measured. The results of the morphometric parameters showed that these reservoirs presented a soft and roughness bottom, with an ellipsoid form and a concave depression that permit the mix up of water and sediments, causing turbidity and broken thermal gradients; their slight slopes allowed the colonization of submerged macrophyte and halophyte plants and improved the incidence of sunlight on water surface increasing evaporation and primary productivity. Dry tropical shallow reservoirs have fluctuations in area, and volume according to the amount of rainfall, the effect of evaporation, temperature, lost volume for irrigation, and other causes. The sand-clay was the most important sediment texture and their values fluctuated with the flooded periods. The concentration-dilution cycle showed a direct relationship in the percentage of organic matter in the soil as well as with pH, soil nitrogen and phosphorus. El Tilzate, El Candelero and El Movil were related by the shore development and high concentrations of organic matter and nitrogen in the soil. Finally, we emphasize the importance of this study, in relation to possible future changes in morphometrical parameters as a consequence of human impact.

  10. Characteristics estimation of coal liquefaction residue; Sekitan ekika zansa seijo no suisan ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Itonaga, M.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Okada, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan)

    1996-10-28

    The paper studied a possibility of estimating characteristics of coal liquefaction residue from liquefaction conditions in the case of fixing coal kind in the NEDOL process coal liquefaction PSU. Wyoming coal was used for the study, and the already proposed simplified liquefaction reaction models were used. Among material balances explained by the models, those of asphaltene, preasphaltene, THF insoluble matters are concerned with residue composition. Ash content is separately calculated from ash balance. Reaction velocity constants of simplified liquefaction reaction models which influence the residue composition were obtained by the multiple regression method from experimental results in the past. The estimation expression of residue viscosity was introduced from residue ash/composition. When the residue composition is estimated by the model from liquefaction conditions, and the residue viscosity is obtained using it, the higher the liquefaction temperature is, the higher the residue viscosity is. The result obtained well agreed the measuring result. The simplified liquefaction model of a certain coal kind has been established, and characteristics of residue can be estimated even at liquefaction conditions which have never been experienced before if there is a certain amount of the accumulated data on residue composition/characteristics. 4 refs., 4 figs., 4 tabs.

  11. Characteristics of fundamental combustion and NOx emission using various rank coals.

    Science.gov (United States)

    Kim, Sung Su; Kang, Youn Suk; Lee, Hyun Dong; Kim, Jae-Kwan; Hong, Sung Chang

    2011-03-01

    Eight types of coals of different rank were selected and their fundamental combustion characteristics were examined along with the conversion of volatile nitrogen (N) to nitrogen oxides (NOx)/fuel N to NOx. The activation energy, onset temperature, and burnout temperature were obtained from the differential thermogravimetry curve and Arrhenius plot, which were derived through thermo-gravimetric analysis. In addition, to derive the combustion of volatile N to NOx/fuel N to NOx, the coal sample, which was pretreated at various temperatures, was burned, and the results were compared with previously derived fundamental combustion characteristics. The authors' experimental results confirmed that coal rank was highly correlated with the combustion of volatile N to NOx/fuel N to NOx.

  12. The role of anthropogenic water reservoirs within the landscapes of mining areas – a case study from the western part of the Upper Silesian Coal Basin

    Directory of Open Access Journals (Sweden)

    Jaruchiewicz Ewelina

    2014-03-01

    Full Text Available A few thousand anthropogenic water reservoirs can be found in the area of the Upper Silesian Coal Basis (USCB located in southern Poland. In this paper the role of such anthropogenic lakes in the landscape of the western part of the USCB was presented and illustrated with the example of Knurów, a mining city, and its immediate surrounding area. The study of landscape changes in this area was carried out on the basis of archival and contemporary cartographic materials, historical sources, and interviews with inhabitants and direct field observations. It was found that the origin of the majority of the water reservoirs is related to hard coal, clay and sand mining. They were created primarily as a result of filling subsidence basins and post-mining excavations with water, as well as being the result of the construction of various hydro-technical facilities (settling ponds, fire protection water reservoirs, etc. In the study area the anthropogenic water reservoirs are of different sizes, shapes and durability and play different roles in the environment. Between 1884 and 2001 their number increased 25-fold, while at the same time their total surface area increased more than 8-fold. The role of the newly created water reservoirs in the landscape primarily involves the transformation of the existing terrestrial ecosystems into wetland ecosystems. The agro-forestry landscape of the late 19th century was transformed into a typically anthropogenic landscape with a dominant share of water reservoirs, settlement ponds and mining waste heaps. The most common species of plants around the water reservoirs are Phragmites australis, Typha latifolia, Ceratophyllum demersum, Elodea canadensis, Potamogeton natans, Lemna sp., Acorus calamus, Myriophyllum verticillatum, Sagittaria sagittifolia, Alisma plantago-aquatica and Glyceria aquatica. The most valuable elements of the flora include Trapa natans and Ruppia maritima, species recognized in Poland as threatened

  13. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    Science.gov (United States)

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane.

  14. Numerical Simulations of Spread Characteristics of Toxic Cyanide in the Danjiangkou Reservoir in China under the Effects of Dam Cooperation

    Directory of Open Access Journals (Sweden)

    Libin Chen

    2014-01-01

    Full Text Available Many accidents of releasing toxic pollutants into surface water happen each year in the world. It is believed that dam cooperation can affect flow field in reservoir and then can be applied to avoiding and reducing spread speed of toxic pollutants to drinking water intake mouth. However, few studies investigated the effects of dam cooperation on the spread characteristics of toxic pollutants in reservoir, especially the source reservoir for water diversion with more than one dam. The Danjiangkou Reservoir is the source reservoir of the China’ South-to-North Water Diversion Middle Route Project. The human activities are active within this reservoir basin and cyanide-releasing accident once happened in upstream inflow. In order to simulate the spread characteristics of cyanide in the reservoir in the condition of dam cooperation, a three-dimensional water quality model based on the Environmental Fluid Dynamics Code (EFDC has been built and put into practice. The results indicated that cooperation of two dams of the Danjiangkou Reservoir could be applied to avoiding and reducing the spread speed of toxic cyanide in the reservoir directing to the water intake mouth for water diversions.

  15. Investigation on the ignition, thermal acceleration and characteristic temperatures of coal char combustion

    International Nuclear Information System (INIS)

    Zhang, Bin; Fu, Peifang; Liu, Yang; Yue, Fang; Chen, Jing; Zhou, Huaichun; Zheng, Chuguang

    2017-01-01

    Highlights: • A new thermal model and measuring method for the ignition temperature are proposed. • Ignition occurs in a region but not a point with ambient conditions changing. • Ignition region is measured from the minimum to maximum ignition temperature. • T_i_g_,_m_a_x of coal char in TG-DSC is in line with the ignition temperature of EFR. - Abstract: Through using a new thermal analysis model and a method of coal/char combustion, the minimum ignition temperature and minimum ignition heat of three different ranks of pulverized coal char were measured by simultaneous Thermogravimetry and Differential Scanning Calorimetry (TG-DSC) experiments. The results show that the ignition of coal char occurs in the range between the minimum ignition temperature and the inflection-point temperature. The thermal acceleration and its gradient G_T increase with increasing heating rate and decrease with increasing coal char rank. The higher the G_T of the coal char, the more easily the ignition occurs and more rapidly the burning and burnout occur. The data show that the G_T of coal char of SLH lignite is 1.6 times more than that of coal char of ZCY bituminous and JWY anthracite in ignition zone, and 3.4 times in burning zone. The characteristic temperatures increase with increasing temperature of prepared char, heating rate and char rank. Moreover, the T_i_g_,_m_a_x calculated in DSC experiment is approximately in line with the ignition temperature obtained in the entrained flow reactor, which demonstrates the feasibility of the proposed theory.

  16. Research on pyrolysis characteristics and kinetics of super fine and conventional pulverized coal

    International Nuclear Information System (INIS)

    Zhang Chaoqun; Jiang Xiumin; Wei Lihong; Wang Hui

    2007-01-01

    Based on isothermal thermogravimetric analysis (TGA) and kinetic equations, the optimization toolbox of MATLAB was applied to study the effects of particle size and heating rate on the pyrolysis characteristics and kinetics and to obtain the mechanism function and kinetic parameters of Yuanbaoshan coal at four different particle sizes and heating rates. The pyrolysis characteristics of the samples were analyzed using thermogravimetric (TG) curves and differential thermogravimetric (DTG) curves. The results show that the coal pyrolysis process is strongly affected by heating rate and particle size. As the heating rate increases, the temperature of volatile matter initiation increases, the total volatile matter evolved decreases and the DTG peak shifts toward higher temperature. As the particle size decreases, the temperature of volatile matter initiation of the coal sample decreases and the maximum rate of mass loss increases. In the pyrolysis of coal, the activation energies of the samples were found to increase with growing particle size and decreasing heating rate for both of the devolatilization temperature stages. In the lower temperature stage, the coal samples show a great difference in mechanism function at different particle sizes and heating rates

  17. Evolution characteristics and application of diamondoids in coal measures

    Directory of Open Access Journals (Sweden)

    Chenchen Fang

    2016-02-01

    Full Text Available As diamondoids have been used to evaluate petroleum and source rocks widely; their origin, evolution, and distribution in petroleum as well as source rocks have attracted ever more attention. Having finished the pyrolysis simulation experiment of the coal measure mudrocks from Xujiahe Formation, Sichuan Basin, results indicated that with the equivalent vitrinite reflectance (EasyRo increasing, diamondoids experience generation (1.0%  1.5%. Throughout the simulation experiment, diamondoid parameters MAI, EAI, and TMAI-1 kept good relationships with maturity within the range of EasyRo 1.5%–2.5%, 1.0%–2.5%, and 1.5%–2.5% respectively, with all of the correlation coefficient (R2 being above 0.7844, this indicated that these parameters can be used to evaluate maturity at these ranges. In addition, the yield ratios A/D, MA/MD, DMA/DMD, and As/Ds also kept good relationships with maturity at the range of EasyRo 1.2%–2.5%, with all of the R2 above 0.9236, this indicated that these ratios can be used to evaluate maturity index at this range.

  18. Combustion characteristics of Malaysian oil palm biomass, sub-bituminous coal and their respective blends via thermogravimetric analysis (TGA).

    Science.gov (United States)

    Idris, Siti Shawalliah; Rahman, Norazah Abd; Ismail, Khudzir

    2012-11-01

    The combustion characteristics of Malaysia oil palm biomass (palm kernel shell (PKS), palm mesocarp fibre (PMF) and empty fruit bunches (EFB)), sub-bituminous coal (Mukah Balingian) and coal/biomass blends via thermogravimetric analysis (TGA) were investigated. Six weight ratios of coal/biomass blends were prepared and oxidised under dynamic conditions from temperature 25 to 1100°C at four heating rates. The thermogravimetric analysis demonstrated that the EFB and PKS evolved additional peak besides drying, devolatilisation and char oxidation steps during combustion. Ignition and burn out temperatures of blends were improved in comparison to coal. No interactions were observed between the coal and biomass during combustion. The apparent activation energy during this process was evaluated using iso-conversional model free kinetics which resulted in highest activation energy during combustion of PKS followed by PMF, EFB and MB coal. Blending oil palm biomass with coal reduces the apparent activation energy value. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Acoustic Emission Characteristics of Gas-Containing Coal during Loading Dilation Process

    Directory of Open Access Journals (Sweden)

    Z. Q. Yin

    2015-12-01

    Full Text Available Raw coal was used as the study object in this paper to identify the evolution characteristics of acoustic emission (AE during the dilation process of gas-containing coal. The coal specimens were stored in gas seal devices filled with gas at different pressures (0, 0.5, 1.0, and 1.5 MPa for 24 h prior to testing. Then, the specimens were tested in a rock-testing machine, and the deformation and crack fracture patterns were recorded by using strain gauges and an AE system. The axial and volumetric strains–stress curves were analyzed in relation to the AE and the failure mode. Results show that as gas pressure increases, the uniaxial compression strength and elasticity modulus of gas-containing coal decreases, whereas the Poisson’s ratio increases. In all the coal specimens, the dilation initiation stress decreases, and the dilation degree increases. During the dilation process, before the loaded coal specimens reach peak stress, and as the load increases, the changes in the specimens and in the AE energy parameter of specimens can be divided into four phases: crack closure deformation, elastic deformation, stable crack propagation, and unstable crack propagation (dilation process. Across the four phases, the AE energy increases evidently during crack closure and elastic deformation but decreases during stable crack propagation. As the gas pressure increases, the AE signal frequency increases from 4.5 KHz to 8.1 KHz during the dilation process. Thus, the gas presence in coal specimens exerts a significant influence on the closure of sample cracks and dilation damage.

  20. [Distribution Characteristics and Pollution Status Evaluation of Sediments Nutrients in a Drinking Water Reservoir].

    Science.gov (United States)

    Huang, Ting-lin; Liu, Fei; Shi, Jian-chao

    2016-01-15

    The main purpose of this paper is to illustrate the influence of nutrients distribution in sediments on the eutrophication of drinking water reservoir. The sediments of three representative locations were field-sampled and analyzed in laboratory in March 2015. The distribution characteristics of TOC, TN and TP were measured, and the pollution status of sediments was evaluated by the comprehensive pollution index and the manual for sediment quality assessment. The content of TOC in sediments decreased with depth, and there was an increasing trend of the nitrogen content. The TP was enriched in surface sediment, implying the nutrients load in Zhoucun Reservoir was aggravating as the result of human activities. Regression analysis indicated that the content of TOC in sediments was positively correlated with contents of TN and TP in sediments. The TOC/TN values reflected that the vascular land plants, which contain cellulose, were the main source of organic matter in sediments. The comprehensive pollution index analysis result showed that the surface sediments in all three sampling sites were heavily polluted. The contents of TN and TP of surface sediments in three sampling sites were 3273-4870 mg x kg(-1) and 653-2969 mg x kg(-1), and the content of TOC was 45.65-83.00 mg x g(-1). According to the manual for sediment quality assessment, the TN, TP and TOC contents in sediments exceed the standard values for the lowest level of ecotoxicity, so there is a risk of eutrophication in Zhoucun Reservoir.

  1. A study on the char burnout characteristics of coal and biomass blends

    Energy Technology Data Exchange (ETDEWEB)

    Behdad Moghtaderi [University of Newcastle, Callaghan, NSW (Australia). Discipline of Chemical Engineering, School of Engineering, Faculty of Engineering and Built Environment

    2007-10-15

    The char burnout characteristics of coal/biomass blends under conditions pertinent to pulverised fuel combustors were investigated by a combined modelling and experimental approach. Results indicate that blending of coal with biomass increases the likelihood of char extinction (i.e. extinction potential of the char particle in the blend), in turn, decreasing the char burnout level. Our modelling results attribute this to a reduction in the char particle size to levels below a critical dimension which appears to be a strong function of the fuel blending ratio (the weight percentage of biomass in the blend), fuel reactivity, char cloud shape and particle density number. It is demonstrated here that the drop in the char burnout level during co-firing can be effectively resolved when a more reactive secondary coal is added to the blend to minimise its extinction potential. 22 refs., 8 figs., 2 tabs.

  2. [Soil organic pollution characteristics and microbial properties in coal mining areas of Mentougou].

    Science.gov (United States)

    Jia, Jian-Li; Zhang, Yue; Wang, Chen; Li, Dong; Liu, Bo-Wen; Liu, Ying; Zhao, Le; Yang, Si-Qi

    2011-03-01

    Soil micro-ecosystem including organic pollution characteristics, basic physicochemical parameters, and microbial properties was analyzed which contaminated with organic pollutants in coal mining area. Results showed that the organic pollution level in coal mining area soils distributed from 0.4 to 1.5 mg/g dry soil, which was 1. 5-6 times as much as the background sample. Furthermore, the column chromatography and GC-MS analysis revealed that content of lightly components including saturated and aromatic hydrocarbons exceeded 40%, specifically was alkenes (> C15), hydrocarbon derivatives, and a small amount aromatic hydrocarbons. Totally, the components of organic pollutants extracted in soils were similar to which in coal gangue samples, illustrating the source of soil pollution to a certain extent in coal mining areas. The physicochemical factors such as nutrient level and moisture contents were not conducive to the growth and reproduction of microbe except pH level, which might show inhibition to microbial activities. Microbial density of pollutant soils in coal mining areas was totally low, with specific amount 10(4)-10(5) cell/g dry soil and FDA activity 2.0-2.9 mg/(g x min). Generally, the microbial density and activity were decreased as the enhancing pollution level. However, in-depth analysis was needed urgently because of the complex impact of environmental conditions like pH, moisture, and nutrition.

  3. Characteristics of carbonized sludge for co-combustion in pulverized coal power plants.

    Science.gov (United States)

    Park, Sang-Woo; Jang, Cheol-Hyeon

    2011-03-01

    Co-combustion of sewage sludge can destabilize its combustion profile due to high volatility, which results in unstable flame. We carried out fuel reforming for sewage sludge by way of carbonization at pyrolysis temperature of 300-500°C. Fuel characteristics of carbonized sludge at each temperature were analyzed. As carbonization temperature increased, fuel ratio increased, volatile content reduced, and atomic ratio relation of H/C and O/C was similar to that of lignite. The analysis result of FT-IR showed the decrease of aliphatic C-H bond and O-C bond in carbonization. In the analysis result of TG-DTG, the thermogravimetry reduction temperature of carbonized sludge (CS400) was proven to be higher than that of dried sludge, but lower than that of sub-bituminous coal. Hardgrove grindability index increased in proportion to fuel ratio increase, where the carbonized sludge value of 43-110 was similar or higher than the coal value of 49-63. As for ash deposits, slagging and fouling index were higher than that of coal. When carbonized sludge (CS400) and coal were co-combusted in 1-10% according to calorific value, slagging tendency was low in all conditions, and fouling tendency was medium or high according to the compositions of coal. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Characteristics of carbonized sludge for co-combustion in pulverized coal power plants

    International Nuclear Information System (INIS)

    Park, Sang-Woo; Jang, Cheol-Hyeon

    2011-01-01

    Co-combustion of sewage sludge can destabilize its combustion profile due to high volatility, which results in unstable flame. We carried out fuel reforming for sewage sludge by way of carbonization at pyrolysis temperature of 300-500 deg. C. Fuel characteristics of carbonized sludge at each temperature were analyzed. As carbonization temperature increased, fuel ratio increased, volatile content reduced, and atomic ratio relation of H/C and O/C was similar to that of lignite. The analysis result of FT-IR showed the decrease of aliphatic C-H bond and O-C bond in carbonization. In the analysis result of TG-DTG, the thermogravimetry reduction temperature of carbonized sludge (CS400) was proven to be higher than that of dried sludge, but lower than that of sub-bituminous coal. Hardgrove grindability index increased in proportion to fuel ratio increase, where the carbonized sludge value of 43-110 was similar or higher than the coal value of 49-63. As for ash deposits, slagging and fouling index were higher than that of coal. When carbonized sludge (CS400) and coal were co-combusted in 1-10% according to calorific value, slagging tendency was low in all conditions, and fouling tendency was medium or high according to the compositions of coal.

  5. In Situ Test Study of Characteristics of Coal Mining Dynamic Load

    Directory of Open Access Journals (Sweden)

    Jiang He

    2015-01-01

    Full Text Available Combination of coal mining dynamic load and high static stress can easily induce such dynamic disasters as rock burst, coal and gas outburst, roof fall, and water inrush. In order to obtain the characteristic parameters of mining dynamic load and dynamic mechanism of coal and rock, the stress wave theory is applied to derive the relation of mining dynamic load strain rate and stress wave parameters. The in situ test was applied to study the stress wave propagation law of coal mine dynamic load by using the SOS microseismic monitoring system. An evaluation method for mining dynamic load strain rate was proposed, and the statistical evaluation was carried out for the range of strain rate. The research results show that the loading strain rate of mining dynamic load is in direct proportion to the seismic frequency of coal-rock mass and particle peak vibration velocity and is in inverse proportion to wave velocity. The high-frequency component damps faster than the low-frequency component in the shockwave propagating process; and the peak particle vibration velocity has a power functional relationship with the transmitting distance. The loading strain rate of mining dynamic load is generally less than class 10−1/s.

  6. Combustion characteristics and kinetic analysis of pulverized coal under different pressure grades

    Directory of Open Access Journals (Sweden)

    Qiwei ZUO

    2016-02-01

    Full Text Available By using thermo gravimetric balance, experimental research on combustion characteristics and dynamics parameters of the typical coal injection from some domestic steelworks are conducted with non-isothermal method. The combustion characteristic parameters of the sample pulverized coal such as ignition temperature, peak temperature at maximum weight loss rate, burnout temperature, general burn exponent(S, and maximum combustion rate are studied under pressure grades of 0.1, 1.1, 2.1, 3.1 and 4.1 MPa, the activation energy (E and pre-exponential factor in the combustion process are calculated. The results show that when the pressure increases from 0.1 to 4.1 MPa, ignition temperature decreases by 85.7 K at most, peak temperature at maximum weight loss rate decreases by 249.3 K at most, burnout temperature decreases by 375 K at most, maximum weight loss rate increases by 10 times, and S increases by 33.6 times at most. It is also shown that there exists a kinetic complementation between E and ln A from the view point of dynamics, and the critical pressure of pulverized coal reaction control requirement and combustion mode transform is 3.1 MPa for the pulverized coal.

  7. Meso- and micropore characteristics of coal lithotypes: Implications for CO2 adsorption

    Science.gov (United States)

    Mastalerz, Maria; Drobniak, A.; Rupp, J.

    2008-01-01

    Lithotypes (vitrain, clarain, and fusain) of high volatile bituminous Pennsylvanian coals (Ro of 0.56-0.62%) from Indiana (the Illinois Basin) have been studied with regard to meso- and micropore characteristics using low-pressure nitrogen and carbon dioxide adsorption techniques, respectively. High-pressure CO2 adsorption isotherms were obtained from lithotypes of the Lower Block Coal Member (the Brazil Formation) and the Springfield Coal Member (the Petersburg Formation), and after evacuation of CO2, the lithotypes were re-analyzed for meso- and micropore characteristics to investigate changes related to high-pressure CO2 adsorption. Coal lithotypes have differing Brunauer-Emmett-Teller (BET) surface areas and mesopore volumes, with significantly lower values in fusains than in vitrains or clarains. Fusains have very limited pore volume in the pore size width of 4-10 nm, and the volume, increases with an increase in pore size, in contrast to vitrain, for which a 4-10 nm range is the dominant pore'Wlidth. For clarain, both pores of 4-10 nm and pores larger than 20 nm contribute substantially to the mesoporosity. Micropore surface areas are the smallest for fusain (from 72.8 to 98.2 m2/g), largest for vitrain (from 125.0 to,158.4 m2 /g), and intermediate for clarain (from 110.5 to 124.4 m2/g). Similar relationships are noted for micropore volumes, and the lower values of these parameters in fusains are related to smaller volumes of all incremental micropore sizes. In the Springfield and the Lower Block Coal Members, among lithotypes studied, fusain has the lowest adsorption capacity. For the Lower Block, vitrain has significantly higher adsorption capacity than fusain and clarain, whereas for the Springfield, vitrain and clarain have comparable but still significantly higher adsorption capacities than fusain. The Lower Block vitrain and fusain have much higher adsorption capacities than those in the Springfield, whereas the clarains of the two coals are comparable

  8. [Quantitative spectrum analysis of characteristic gases of spontaneous combustion coal].

    Science.gov (United States)

    Liang, Yun-Tao; Tang, Xiao-Jun; Luo, Hai-Zhu; Sun, Yong

    2011-09-01

    Aimed at the characteristics of spontaneous combustion gas such as a variety of gases, lou limit of detection, and critical requirement of safety, Fourier transform infrared (FTIR) spectral analysis is presented to analyze characteristic gases of spontaneous combustion In this paper, analysis method is introduced at first by combing characteristics of absorption spectra of analyte and analysis requirement. Parameter setting method, sample preparation, feature variable abstract and analysis model building are taken into consideration. The methods of sample preparation, feature abstraction and analysis model are introduced in detail. And then, eleven kinds of gases were tested with Tensor 27 spectrometer. CH4, C2H6, C3H8, iC4H10, nC4H10, C2 H4, C3 H6, C3 H2, SF6, CO and CO2 were included. The optical path length was 10 cm while the spectra resolution was set as 1 cm(-1). The testing results show that the detection limit of all analytes is less than 2 x 10(-6). All the detection limits fit the measurement requirement of spontaneous combustion gas, which means that FTIR may be an ideal instrument and the analysis method used in this paper is competent for spontaneous combustion gas measurement on line.

  9. Structure and Filling Characteristics of Paleokarst Reservoirs in the Northern Tarim Basin, Revealed by Outcrop, Core and Borehole Images

    Directory of Open Access Journals (Sweden)

    Tian Fei

    2017-06-01

    Full Text Available The Ordovician paleokarst reservoirs in the Tahe oilfield, with burial depths of over 5300 m, experienced multiple phases of geologic processes and exhibit strong heterogeneity. Core testing can be used to analyse the characteristics of typical points at the centimetre scale, and seismic datasets can reveal the macroscopic outlines of reservoirs at the >10-m scale. However, neither method can identify caves, cave fills and fractures at the meter scale. Guided by outcrop investigations and calibrations based on core sample observations, this paper describes the interpretation of high longitudinal resolution borehole images, the identification of the characteristics of caves, cave fills (sedimentary, breccia and chemical fills and fractures in single wells, and the identification of structures and fill characteristics at the meter scale in the strongly heterogeneous paleokarst reservoirs. The paleogeomorphology, a major controlling factor in the distribution of paleokarst reservoirs, was also analysed. The results show that one well can penetrate multiple cave layers of various sizes and that the caves are filled with multiple types of fill. The paleogeomorphology can be divided into highlands, slopes and depressions, which controlled the structure and fill characteristics of the paleokarst reservoirs. The results of this study can provide fundamental meter-scale datasets for interpreting detailed geologic features of deeply buried paleocaves, can be used to connect core- and seismic-scale interpretations, and can provide support for the recognition and development of these strongly heterogeneous reservoirs.

  10. Berau coal in East Kalimantan; Its petrographics characteristics and depositional environment

    Directory of Open Access Journals (Sweden)

    Nana Suwarna

    2014-06-01

    Full Text Available http://dx.doi.org/10.17014/ijog.vol2no4.20071To asses the characteristics of the Early to Middle Miocene Berau coal in the Berau Basin, leading to interpretation of coal depositional environments, some fresh outcrop and subcrop samples and also drill cores of the coals have been analyzed microscopically. Coal petrographic analysis was performed on twenty four coal samples from the Middle Miocene Lati Formation. Vitrinite, present in a high value, and ranging between 66.2 - 96.2%, is dominated by vitrinite B. On the other hand, inertinite and exinite, showing a similar value, exist in a low to moderate amount. Vitrinite reflectance, present in a low value, varies from 0.40 - 0.58%. Low mineral matter content is dominated by clay minerals (0.4 - 6.6% with minor pyrite. Transitions from wet and very wet forested swamps to drier conditions with lower tree density are indicated by the higher content of vitrinite B, whilst a reverse trend is indicated by the lower content of vitrinite A. Petrographic indices obtained from facies diagnostic macerals show that an accumulation of the ancient peats under prevailing relatively wet limited influx clastic marsh to very wet forest swamps or moors is considered. The composition of the coal samples supports the interpretation of a system of fluvial to meandering streams in an upper delta plain environment. The original peat-forming vegetation was composed mainly of cellulose rich, shrub-like plants, tree ferns, herbaceous plant communities, with minor amount of trees. Thereby, the organic facies concept is thus applicable in basin studies context and has potential to become an additional tool for depositional environment interpretation.  

  11. Agglomeration and reaction characteristics of various coal chars in fluidized-bed coal gasifier; Ryudoso sekitan gas ka ronai deno sekitan no gyoshu tokusei to hanno tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Uemiya, S.; Aoki, K.; Mori, S.; Kojima, T. [Seikei University, Tokyo (Japan). Faculty of Engineering

    1996-10-28

    With relation to the coals delivered as common samples in the coal fundamental technology development project, an experimental study was conducted on agglomeration characteristics and reaction characteristics in the fluidized-bed coal gasifier. For the experiment, used was a fluidized bed gasifier inserted with a cone-shape dispersion plate with a nozzle in the center. After raising the temperature of the gasifier up to 773K, gasification was conducted sending to the gasifier air from the nozzle and steam from the dispersion plate. The mean particle diameter and gas concentration of chars were measured till the temperature reaches 1373K. As a result of the experiment, it was confirmed that the carbon conversion ratio increases with a decrease in coalification degree of the coal. Moreover, influence of the coal kind was markedly observed at the grid zone of the lower part of the bed, and it was clarified that the lower carbon content ratio the coal kind has, the faster the speed of CO formation and water gasification get. The agglomeration temperature of charcoal which is a product of the condensate is lower by as many as several hundred K than the point of softening, and it was considered to be necessary to study the relation with the temperature distribution in the bed. 3 refs., 3 figs., 1 tab.

  12. Study of gas holdup and pressure characteristics in a column flotation cell using coal

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, S.C.; Kundu, G.; Mukherjee, D. [Indian Institute of Technology, Kharagpur (India). Dept. of Chemical Engineering

    2010-07-15

    Present work has been carried out to observe the effect of process variables (gas flow rate, feed flow rate, solid concentration and frother concentration) on gas holdup and pressure characteristics in flotation column using coal. Gas holdup has been estimated using phase separation method while piezometers have been used to obtain column's axial pressure profile. It was observed that gas holdup in collection zone was affected by both air as well as feed flow rates. Up to 6% change in gas holdup may occur when the feed flow rate changes from 1-2 cm/s. It was also observed that addition of coal decreased the gas holdup while addition of methyl isobutyl carbinol (MIBC) had opposite effect. Almost linear variation in columns axial pressure characteristics has been observed with gas flow rate. An empirical relationship between gas holdup in the flotation column with column's axial pressure difference was developed.

  13. Damage Effects and Fractal Characteristics of Coal Pore Structure during Liquid CO2 Injection into a Coal Bed for E-CBM

    Directory of Open Access Journals (Sweden)

    Li Ma

    2018-05-01

    Full Text Available Pore structure has a significant influence on coal-bed methane (CBM enhancement. Injecting liquid CO2 into coal seams is an effective way to increase CBM recovery. However, there has been insufficient research regarding the damage effects and fractal characteristics of pore structure at low temperature induced by injecting liquid CO2 into coal samples. Therefore, the methods of low-pressure nitrogen adsorption-desorption (LP-N2-Ad and mercury intrusion porosimetry (MIP were used to investigate the damage effects and fractal characteristics of pore structure with full aperture as the specimens were frozen by liquid CO2. The adsorption isotherms revealed that the tested coal samples belonged to type B, indicating that they contained many bottle and narrow-slit shaped pores. The average pore diameter (APD; average growth rate of 18.20%, specific surface area (SSA; average growth rate of 7.38%, and total pore volume (TPV; average growth rate of 18.26% increased after the specimens were infiltrated by liquid CO2, which indicated the generation of new pores and the transformation of original pores. Fractal dimensions D1 (average of 2.58 and D2 (average of 2.90 of treated coal samples were both larger the raw coal (D1, average of 2.55 and D2, average of 2.87, which indicated that the treated specimens had more rough pore surfaces and complex internal pore structures than the raw coal samples. The seepage capacity was increased because D4 (average of 2.91 of the treated specimens was also higher than the raw specimens (D4, average of 2.86. The grey relational coefficient between the fractal dimension and pore structure parameters demonstrated that the SSA, APD, and porosity positively influenced the fractal features of the coal samples, whereas the TPV and permeability exerted negative influences.

  14. Effect of structural heterogeneity water-coal fuel conditions and characteristics of ignition

    Directory of Open Access Journals (Sweden)

    Syrodoy S.V.

    2015-01-01

    Full Text Available The problem of the particle ignition of coal-water fuel (CWF with a joint course of the main processes of a thermal (thermal conductivity, evaporation, filtration heat and mass transfer, thermal decomposition of the organic part has been solved. According to the results of numerical simulation ways of describing the extent of the influence of the thermophysical properties on the characteristics and conditions of ignition WCF have been set.

  15. [Emission characteristics of PM10 from coal-fired industrial boiler].

    Science.gov (United States)

    Li, Chao; Li, Xing-Hua; Duan, Lei; Zhao, Meng; Duan, Jing-Chun; Hao, Ji-Ming

    2009-03-15

    Through ELPI (electrical low-pressure impactor) based dilution sampling system, the emission characteristics of PM10 and PM2.5 was studied experimentally at the inlet and outlet of dust catchers at eight different coal-fired industrial boilers. Results showed that a peak existed at around 0.12-0.20 microm of particle size for both number size distribution and mass size distribution of PM10 emitted from most of the boilers. Chemical composition analysis indicated that PM2.5 was largely composed of organic carbon, elementary carbon, and sulfate, with mass fraction of 3.7%-21.4%, 4.2%-24.6%, and 1.5%-55.2% respectively. Emission factors of PM10 and PM2.5 measured were 0.13-0.65 kg x t(-1) and 0.08-0.49 kg x t(-1) respectively for grate boiler using raw coal, and 0.24 kg x t(-1) and 0.22 kg x t(-1) for chain-grate boiler using briquette. In comparison, the PM2.5 emission factor of fluidized bed boiler is 1.14 kg x t(-1), much her than that of grate boiler. Due to high coal consumption and low efficiency of dust separator, coal-fired industrial boiler may become the most important source of PM10, and should be preferentially controlled in China.

  16. Effects of catalysts on combustion characteristics and kinetics of coal-char blends

    Science.gov (United States)

    Hu, Yingjie; Wang, Zhiqiang; Cheng, Xingxing; Liu, Ming; Ma, Chunyuan

    2018-04-01

    The effects of Fe2O3, CaO, and MnO2 on the combustion characteristics and kinetics of coal-char blends were investigated using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results indicated that catalysts exhibited positive effects on the combustion characteristics of coal-char blends, especially in the initial period of coal-char blends combustion. With catalysts addition (mass 1.5%), it could improves volatile matter release, and reduces ignition point, promotes char to begin burning under lower temperature. The ignition index (C) was increased, respectively, by 27% for Fe2O3, 6% for CaO, 11.3% for MnO2, and the combustion characteristic index ( S ) was increased respectively, by 29% for Fe2O3, 5% for CaO, 8.3% for MnO2. In addition, two kinetic models (R2 and F1) were adopted to calculate the kinetic parameters in different stage of combustion processes. The results showed that with Fe2O3 or CaO addition, the activation energy at second stage decreases from 86.0 KJ/mol to 76.92 KJ/mol and 75.12 KJ/mol, respectively. There are no obvious decreases at the third stage of samples combustion process.

  17. Effect of Discrete Fracture Network Characteristics on the Sustainability of Heat Production in Enhanced Geothermal Reservoirs

    Science.gov (United States)

    Riahi, A.; Damjanac, B.

    2013-12-01

    Viability of an enhanced or engineered geothermal reservoir is determined by the rate of produced fluid at production wells and the rate of temperature drawdown in the reservoir as well as that of the produced fluid. Meeting required targets demands sufficient permeability and flow circulation in a relatively large volume of rock mass. In-situ conditions such overall permeability of the bedrock formation, magnitude and orientation of stresses, and the characteristics of the existing Discrete Fracture Network (DFN) greatly affect sustainable heat production. Because much of the EGS resources are in formations with low permeability, different stimulation techniques are required prior to the production phase to enhance fluid circulation. Shear stimulation or hydro-shearing is the method of injecting a fluid into the reservoir with the aim of increasing the fluid pressure in the naturally fractured rock and inducing shear failure or slip events. This mechanism can enhance the system's permeability through permanent dilatational opening of the sheared fractures. Using a computational modeling approach, the correlation between heat production and DFN statistical characteristics, namely the fracture length distribution, fracture orientation, and also fracture density is studied in this paper. Numerical analyses were completed using two-dimensional distinct element code UDEC (Itasca, 2011), which represents rock masses as an assembly of interacting blocks separated by fractures. UDEC allows for simulation of fracture propagation along the predefined planes only (i.e., the trajectory of the hydraulic fracture is not part of the solution of the problem). Thus, the hydraulic fracture is assumed to be planar, aligned with the direction of the major principal stress. The pre-existing fractures were represented explicitly. They are discontinuities which deform elastically, but also can open and slip (Coulomb slip law) as a function of pressure and total stress changes. The fluid

  18. Study on the structure and gasification characteristics of selected South African bituminous coals in fluidised bed gasification

    CSIR Research Space (South Africa)

    Oboirien, BO

    2011-04-01

    Full Text Available . The microstructural characteristics of the parent coals and their resultant chars were determined using XRD, FT-IR, Raman and petrographic analysis. The microstructural changes that occurred in the organic (maceral) and the inorganic (mineral) fractions...

  19. Co-pyrolysis characteristics and kinetics of coal and plastic blends

    International Nuclear Information System (INIS)

    Zhou Limin; Luo Taian; Huang Qunwu

    2009-01-01

    Co-pyrolysis behaviors of different plastics (high density polyethylene, low density polyethylene and polypropylene), low volatile coal (LVC) and their mixtures were investigated by TGA. Experiments were conducted under N 2 atmosphere at heating rate of 20 deg. C/min from room temperature to 750 deg. C. The results showed that the thermal degradation temperature range of plastic was 438-521 deg. C, while that of coal (LVC) was 174-710 deg. C. Plastics showed similar pyrolysis characteristics due to similar chemical bonds in their molecular structures. The overlapping degradation temperature interval between coal and plastic provide an opportunity for free radicals from coal pyrolysis to participate in the reactions of plastic decomposition. The difference of weight loss percent (ΔW) between experimental and theoretical ones, calculated as an algebraic sum of those from each separated component, ΔW is 2.0-2.7% at the pyrolysis temperature higher than 530 deg. C, which indicates that the synergistic effect during pyrolysis occurs mainly in the high temperature region. The kinetic studies were performed according to Coats and Redfern method for first-order reaction. It was found that for plastics (HDPE, LDPE and PP), the pyrolysis process can be described by one first-order reaction. However, for LVC and LVC/plastic blends, this process can be described by three and four consecutive first-order reactions, respectively. The estimated kinetic parameters viz., activation energies and pre-exponential factors for coal, plastic and their blends, were found to be in the range of 35.7-572.8 kJ/mol and 27-1.7 x 10 38 min -1 , respectively

  20. [Macromolecular aromatic network characteristics of Chinese power coal analyzed by synchronous fluorescence and X-ray diffraction].

    Science.gov (United States)

    Ye, Cui-Ping; Feng, Jie; Li, Wen-Ying

    2012-07-01

    Coal structure, especially the macromolecular aromatic skeleton structure, has a strong influence on coke reactivity and coal gasification, so it is the key to grasp the macromolecular aromatic skeleton coal structure for getting the reasonable high efficiency utilization of coal. However, it is difficult to acquire their information due to the complex compositions and structure of coal. It has been found that the macromolecular aromatic network coal structure would be most isolated if small molecular of coal was first extracted. Then the macromolecular aromatic skeleton coal structure would be clearly analyzed by instruments, such as X-ray diffraction (XRD), fluorescence spectroscopy with synchronous mode (Syn-F), Gel permeation chromatography (GPC) etc. Based on the previous results, according to the stepwise fractional liquid extraction, two Chinese typical power coals, PS and HDG, were extracted by silica gel as stationary phase and acetonitrile, tetrahydrofuran (THF), pyridine and 1-methyl-2-pyrollidinone (NMP) as a solvent group for sequential elution. GPC, Syn-F and XRD were applied to investigate molecular mass distribution, condensed aromatic structure and crystal characteristics. The results showed that the size of aromatic layers (La) is small (3-3.95 nm) and the stacking heights (Lc) are 0.8-1.2 nm. The molecular mass distribution of the macromolecular aromatic network structure is between 400 and 1 130 amu, with condensed aromatic numbers of 3-7 in the structure units.

  1. Effect of reservoir characteristics on the response of concrete gravity dams

    International Nuclear Information System (INIS)

    Baumber, T.; Ghobarah, A.

    1992-01-01

    In most previous analyses of dam responses to earthquake ground motion, the upstream reservoir is assumed to be infinite in length with horizontal bottom. This is rarely the actual geometry of a reservoir, as the upstream valley typically has complex geometry. A study was carried out to examine the effects of the geometry of the reservoir on the dynamic behavior of the monolith. The dam-foundation-reservoir system is modelled using a sub-structuring approach. The reservoir is modelled using a finite element formulation. The absorptive capacity of the reservoir's foundation is idealized as a one-dimensional boundary condition at the reservoir-foundation interface. The reservoir bottom is assumed to be sloping. It was found that the assumed shape of the upstream reservoir significantly affects the overall response of the dam-foundation-reservoir system. The frequencies and magnitudes of the response peaks are affected by the geometry of the reservoir. It was also found that the value of the wave reflection coefficient at the reservoir bottom has a significant effect on the system's response. 6 refs., 5 figs

  2. Effect of combustion characteristics on wall radiative heat flux in a 100 MWe oxy-coal combustion plant

    Energy Technology Data Exchange (ETDEWEB)

    Park, S.; Ryu, C. [Sungkyunkwan Univ., Suwon (Korea, Republic of). School of Mechanical Engineering; Chae, T.Y. [Sungkyunkwan Univ., Suwon (Korea, Republic of). School of Mechanical Engineering; Korea Institute of Industrial Technology, Cheonan (Korea, Republic of). Energy System R and D Group; Yang, W. [Korea Institute of Industrial Technology, Cheonan (Korea, Republic of). Energy System R and D Group; Kim, Y.; Lee, S.; Seo, S. [Korea Electric Power Research Institute (KEPRI), Daejeon (Korea, Republic of). Power Generation Lab.

    2013-07-01

    Oxy-coal combustion exhibits different reaction, flow and heat transfer characteristics from air-coal combustion due to different properties of oxidizer and flue gas composition. This study investigated the wall radiative heat flux (WRHF) of air- and oxy-coal combustion in a simple hexahedral furnace and in a 100 MWe single-wall-fired boiler using computational modeling. The hexahedral furnace had similar operation conditions with the boiler, but the coal combustion was ignored by prescribing the gas properties after complete combustion at the inlet. The concentrations of O{sub 2} in the oxidizers ranging between 26 and 30% and different flue gas recirculation (FGR) methods were considered in the furnace. In the hexahedral furnace, the oxy-coal case with 28% of O{sub 2} and wet FGR had a similar value of T{sub af} with the air-coal combustion case, but its WRHF was 12% higher. The mixed FGR case with about 27% O{sub 2} in the oxidizer exhibited the WRHF similar to the air-coal case. During the actual combustion in the 100 MWe boiler using mixed FGR, the reduced volumetric flow rates in the oxy-coal cases lowered the swirl strength of the burners. This stretched the flames and moved the high temperature region farther to the downstream. Due to this reason, the case with 30% O{sub 2} in the oxidizers achieved a WRHF close to that of air-coal combustion, although its adiabatic flame temperature (T{sub af}) and WHRF predicted in the simplified hexahedral furnace was 103 K and 10% higher, respectively. Therefore, the combustion characteristics and temperature distribution significantly influences the WRHF, which should be assessed to determine the ideal operating conditions of oxy- coal combustion. The choice of the weighted sum of gray gases model (WSGGM) was not critical in the large coal-fired boiler.

  3. Water-Sensitivity Characteristics of Briquettes Made from High-Rank Coal

    Directory of Open Access Journals (Sweden)

    Geng Yunguang

    2016-01-01

    Full Text Available In order to study the water sensitivity characteristics of the coalbed methane (CBM reservoir in the southern Qinshui Basin, the scanning electron microscopy, mineral composition and the water sensitivity of main coalbed 3 cores were tested and analyzed. Because CBM reservoirs in this area are characterized by low porosity and low permeability, the common water sensitivity experiment of cores can’t be used, instead, the briquettes were chose for the test to analysis the water sensitivity of CBM reservoirs. Results show that: the degree of water sensitivity in the study area varies from week to moderate. The controlling factors of water sensitivity are clay mineral content and the occurrence type of clay minerals, permeability and liquid flow rate. The water sensitivity damage rate is positively correlated with clay mineral content and liquid flow rate, and is negatively correlated with core permeability. The water sensitivity of CBM reservoir exist two damage mechanisms, including static permeability decline caused by clay mineral hydration dilatation and dynamic permeability decline caused by dispersion/migration of clay minerals.

  4. Sorption characteristic of coal as regards of gas mixtures emitted in the process of the self-heating of coal

    Directory of Open Access Journals (Sweden)

    Wojtacha-Rychter Karolina

    2017-01-01

    Full Text Available One of the most challenging tasks in the coal mining sector is the detection of endogenous fire risks. Under field conditions, the distance between the points where samples for the analyses are collected and the actual place where coal self-heating takes place may be quite remote. Coal is a natural sorbent with a diverse character of pore structures which are surrounded by fractures and cleavage planes constituting ideal spaces for the flow and adsorption of gases. The gases (methane, ethane, ethylene, propane, propylene, acetylene, carbon dioxide, carbon monoxide, hydrogen released from the source of fire migrate through the seam and may be subject to adsorption, or they may cause the desorption of gases accumulated in coal. Therefore, the values of reference sample concentrations may be overstated or understated, respectively. The objective of this experimental study was to investigate the adsorption phenomena accompanying the flow of a multi-component gas mixture through a coal bed which may occur in situ. The research was conducted by means of a method based on a series of calorimetric/chromatographic measurements taken to determine the amount of gases released during coal heating at various temperatures under laboratory conditions. Based on the results obtained in the course of the experiments, it was concluded that the amount of gas adsorbed in the seam depends on the type of coal and the gas. Within the multi-component gas mixture, hydrocarbons demonstrated the largest sorption capacity, especially as concerns propylene.

  5. Biological and ecological characteristics of Pterocuma pectinata (Malacostraca, Cumacea in Sasyk Reservoir

    Directory of Open Access Journals (Sweden)

    А. A. Khalaim

    2016-02-01

    Full Text Available Sasyk (Kunduk – estuary in the North-Western Black Sea region, is located 120 kmsouth-west of Odessa. In 1979–1980 Sasyk was separated from the sea by a dam, connected by a canal with the Danube and transformed into a reservoir. The fauna of Sasyk underwent significant changes and continues to adapt to the new conditions. This process is of great theoretical and practical interest. Cumacea – a small order, numbering about 600 species; is represented in the Black Sea-Azov basin by 23 species, 11 of them belong to the Caspian complex. Due to their high quantity indicators, they play a significant role in the diet of many species of fish. Pterocuma pectinata (Sowinski, 1893 is the most abundant species of cumacean not only in the Sasyk Reservoir, but also in many bodies of water in the region. However, the biology and ecology of this group of animals has been very inadequately studied. The material for these studies was provided by 120 benthic samples collected from 41 stations in the Sasyk Reservoir in the vegetation period 2013–2014. In this study we also used the material collected by means of H. Hungerford underwater light traps. In total 4,000 specimens of cumaceans were processed. This article shows the results of the studyof the post-embryonic development, fertility and size-mass characteristic of P. pectinata in Sasyk Reservoir. For both sexes for age stages have been distinguished and described for cumaceans: «manca», youth, prebreeding and breeding. Between breeding cycles, females live through one more preparatory (intermediate stage; the males die. This article provides a detailed morphological and morphometric description of all the stages of the ontogeny of cumaceans. The ratio of number of cumaceans at different stages of ontogeny varies considerably with the seasons. In the summer sexual development of cumacean occurs earlier than in the less warm seasons. A directly proportional relationship was found between body length

  6. Leaching characteristics of trace elements in desulfurization gypsum from a coal-fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y.K.; Zhuo, Y.Q.; Zhu, Z.W.; Chen, C.H. [Tsinghua Univ., Beijing (China). Inst. of Thermal Engineering

    2013-07-01

    The contents and leaching characteristics of Cr, Cd, As, Pb and Se in FGD gypsum from a 200 MW coal-fired power plant were investigated in this study. Experimental results revealed that: the leaching characteristics of As and Se were similar, both leaching rates were not obviously affected by pH but increased with increase of the liquid-solid ratio. Pb and Cr had similar leaching characteristics, their leaching rates were closely related with the pH of leaching solution and increased with the lowering of pH and both increased with the increasing of solid-liquid ratio. Along with the increase of the liquid-solid ratio, the leaching gradually achieved balance, and the balanced liquid-solid ratio was bigger when pH of leaching solution was lower. Cd content of leaching solution was below detect limit, and thus failed to get its leaching characteristics. The order of trace element content in leaching solution is Pb < Cr < As < Se, and the order of leaching rates is Cr < As < Pb < Se. BCR extraction procedure revealed that trace elements in FGD gypsum were mainly existed as available fraction and migration ability was stronger than that of trace elements in fly ash from coal-fired power plants.

  7. 13C-NMR Study on Structure Evolution Characteristics of High-Organic-Sulfur Coals from Typical Chinese Areas

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    Qiang Wei

    2018-02-01

    Full Text Available The structure evolution characteristics of high-organic-sulfur (HOS coals with a wide range of ranks from typical Chinese areas were investigated using 13C-CP/MAS NMR. The results indicate that the structure parameters that are relevant to coal rank include CH3 carbon (fal*, quaternary carbon, CH/CH2 carbon + quaternary carbon (falH, aliphatic carbon (falC, protonated aromatic carbon (faH, protonated aromatic carbon + aromatic bridgehead carbon (faH+B, aromaticity (faCP, and aromatic carbon (farC. The coal structure changed dramatically in the first two coalification jumps, especially the first one. A large number of aromatic structures condensed, and aliphatic structures rapidly developed at the initial stage of bituminous coal accompanied by remarkable decarboxylation. Compared to ordinary coals, the structure evolution characteristics of HOS coals manifest in three ways: First, the aromatic CH3 carbon, alkylated aromatic carbon (faS, aromatic bridgehead carbon (faB, and phenolic ether (faP are barely relevant to rank, and abundant organic sulfur has an impact on the normal evolution process of coal. Second, the average aromatic cluster sizes of some super-high-organic-sulfur (SHOS coals are not large, and the extensive development of cross bonds and/or bridged bonds form closer connections among the aromatic fringes. Moreover, sulfur-containing functional groups are probably significant components in these linkages. Third, a considerable portion of “oxygen-containing functional groups” in SHOS coals determined by 13C-NMR are actually sulfur-containing groups, which results in the anomaly that the oxygen-containing structures increase with coal rank.

  8. Characteristic of Soil Nutrients Loss in Beiyunhe Reservoir Under the Simulated Rainfall

    Directory of Open Access Journals (Sweden)

    LIU Cao

    2016-05-01

    Full Text Available Field nutrient loss from soil became the major factor of the water pollution control in countryside in China. Beiyunhe reservoir is located in semiarid zone, where field nutrient loss distributed in summer. To assess the flied nutrient loss in Beiyunhe reservoir, we conducted experiments to study the characteristic of soil nutrients loss by analysis of the content of runoff water, soil nutrients and runoff water sediment under simulated rainfall. The results showed that the runoff happened in the rainstorm. In runoff water, the content of TN was 4.7~11.3 mg·L-1, ammonia nitrogen and nitrate nitrogen accounted for 44.51% of TN; the content of P was 0.66~1.35 mg·L-1, water soluble phosphorus accounted for 54.08% of TP. And the main loss of nutrients was in the surface soil, the loss of TN, NH4+-N, NO3--N, TP and DP were 29.79%, 52.09%, 10.21%, 16.48% and 5.27%, respectively. However, the most of field nutrient loss were in runoff sediment, the content of TN and TP were 0.66~1.27 mg·g-1 and 14.73~20 mg·g-1 in sediment, and TN and TP account for 82.28% and 99.89% of total loss of nutrient. After the rainstorm, the macro-aggregates were reduced 8.8%, and the micro-aggregates increased 9.5%.

  9. Pore characteristics of shale gas reservoirs from the Lower Paleozoic in the southern Sichuan Basin, China

    Directory of Open Access Journals (Sweden)

    Xianqing Li

    2016-06-01

    Full Text Available Data was acquired from both the drillings and core samples of the Lower Paleozoic Qiongzhusi and Longmaxi Formations' marine shale gas reservoirs in the southern Sichuan Basin by means of numerous specific experimental methods such as organic geochemistry, organic petrology, and pore analyses. Findings helped determine the characteristics of organic matter, total porosity, microscopic pore, and pore structure. The results show that the Lower Paleozoic marine shale in the south of the Sichuan Basin are characterized by high total organic carbon content (most TOC>2.0%, high thermal maturity level (RO = 2.3%–3.8%, and low total porosity (1.16%–6.87%. The total organic carbon content and thermal maturity level of the Qiongzhusi Formation shale are higher than those of the Longmaxi Formation shale, while the total porosity of the Qiongzhusi Formation shale is lower than that of the Longmaxi Formation shale. There exists intergranular pore, dissolved pore, crystal particle pore, particle edge pore, and organic matter pore in the Lower Paleozoic Qiongzhusi Formation and Longmaxi Formation shale. There are more micro-nano pores developed in the Longmaxi Formation shales than those in the Qiongzhusi Formation shales. Intergranular pores, dissolved pores, as well as organic matter pores, are the most abundant, these are primary storage spaces for shale gas. The microscopic pores in the Lower Paleozoic shales are mainly composed of micropores, mesopores, and a small amount of macropores. The micropore and mesopore in the Qiongzhusi Formation shale account for 83.92% of the total pore volume. The micropore and mesopore in the Longmaxi Formation shale accounts for 78.17% of the total pore volume. Thus, the micropores and mesopores are the chief components of microscopic pores in the Lower Paleozoic shale gas reservoirs in the southern Sichuan Basin.

  10. Main economic characteristics of new plant for underground gasification of coal. [5 planned USSR commercial installations

    Energy Technology Data Exchange (ETDEWEB)

    Leshchinskii, B F; Markman, L M

    1957-01-01

    As a result of experimental investigations, the erection of five large-capacity, industrial, underground gasification stations is planned. The locations and chief customers of the five stations are listed and their characteristics are as follows: 1. North Tula Station will use brown coal that averages 30 percent moisture and 23.1 percent ash. The coalbed, 1.5 meters thick, is horizontal and lies at a depth of 50 meters. Total reserves are estimated at 10.7 million tons and industrial reserves at 7 million tons. 2. Gorlovsky Station will use brown coal, averaging 30 percent water and 21 to 27.3 percent ash. The coalbed, 2.1 to 2.7 meters thick, is horizontal and lies at a depth of 35 to 60 meters. Total reserves are 105.4 million tons; industrial reserves are 73.5 million tons. 3. South Abinsk Station will use hard coal in beds 0.83 to 20 meters thick and contain 38 percent water and 9.4 percent ash. The angle of dip ranges from 60 to 70/sup 0/. The coal averages 330 meters from the surface. Total reserves are 98 million tons; industrial reserves are 58.5 million tons. 4. Stalinsk Station will use a semianthracite containing 12 to 15 percent ash and 7.7 to 12 percent volatile matter. The beds are 0.8 to 8.3 meters thick; the angle of dip ranges from 35 to 75/sup 0/. Total reserves are 287.6 million tons; reserves for gasification are 74.5 million tons. Depth from surface is 290 to 460 meters. 5. South Kuzbass Station will use hard coal that contains 4 to 19 percent ash and 8 to 15 percent volatiles. The beds are from 0.62 to 5.64 meters thick; the angle of dip ranges from 15 to 70/sup 0/. Total reserves are 156.9 million tons; industrial reserves are 105.5 million tons. The basic economic and technical figures for all five stations are listed. Capital investment costs and costs per unit of fuel are compared with those of conventional coal mines.

  11. Monitoring of qualitative characteristics of coal in mines and power plants

    International Nuclear Information System (INIS)

    Cervenka, M.; Krouzek, J.

    1991-01-01

    The basic qualitative characteristic of coal is its heating value, which is dependent on its noncombustible content and moisture. Sensors which have been developed for coal quality monitoring include two-channel radiometric ash meters, moisture meters and neutron sulfur analyzers. They are complemented with integrating balances and automated samplers and computer techniques. A complex quality monitoring system has been implemented in the North Bohemian localities of Vrsany and Most. The gamma ash meter is fitted with a scintillation counter. The measurement is continuous and contactless. A German ash meter equipped with a Geiger-Mueller tube is also mentioned. A continuous neutron analyzer is used for measuring the sulfur content; it is based on radiative capture of thermal neutrons. Described are also the method of coal weighing, the automated samplers, the central computer system and the software used. The results obtained with the systems implemented are summarized. The poor reliability of the Czechoslovak computer hardware poses problems. (M.D.). 7 figs., 6 tabs., 5 refs

  12. Characteristic Study of Shenmu Bituminous Coal Combustion with Online TG-MS-FTIR

    Science.gov (United States)

    Pan, Guanfu

    2018-01-01

    The combustion characteristics of Shenmu bituminous pulverized coal (SBC) were comprehensively investigated with a combined TG-MS-FTIR system by considering the effect of particle size, heating rate and total flowrate. The combustion products were accurately quantified by normalization and numerical analysis of MS results. The results indicate that the decrease of the particle size, heating rate and total flowrate result in lower ignition and burnout temperatures. The activation energy tends to be lower with smaller particle size, lower heating rate and total flowrate. The MS and FTIR results demonstrate that lower concentrations of different products, such as NO, NO2, HCN, CH4 and SO2 were produced with smaller particle size, slower heating rate and lower total flowrate. The decrease of particle size would lead to more contact area with oxygen and slower heating rate could provide more sufficient time for the diffusion. High total flowrate would reduce the oxygen adsorbability on the coal particle surface and shorten the residence time of oxygen, which makes the ignition difficult to occur. This work will guide to understand the combustion kinetics of pulverized coals and be beneficial to control the formation of pollutants.

  13. Effect of dispersing and stabilizing additives on rheological characteristics of the upgraded brown coal water mixture

    International Nuclear Information System (INIS)

    Umar, Datin Fatia; Muta'alim; Usui, Hiromoto; Komoda, Yoshiyuki

    2009-01-01

    Upgraded brown coal water mixture (UBCWM) preparation by using an Indonesian upgraded coal produced by upgraded brown coal (UBC) process, was carried out to study the effect of dispersing and stabilizing additives on rheological behavior of the UBCWM. Three kinds of anionic dispersing additives, naphthalene sulfonic formaldehyde condensate (NSF), poly (meth) acrylate (PMA) and poly styrene sulfonic acid (PSS) and three kinds of stabilizing additives, carboxyl methyl cellulose (CMC), rhansam gum (S-194) and gellan gum (S-60) were used in this study. Results indicate that the addition of NSF 0.3 wt.% together with S-194 0.01 wt.% is effective in preparing UBCWM with good slurryability and stability, based on its rheological characteristics with the apparent viscosity at shear rate of 100 s - 1 and yield stress at zero point of shear rate. The rheological behavior of all of the UBCWM that prepared, exhibits non-Newtonian Bingham plastic. From the economical point of view, the price of S-194 is expensive. On the other hand, CMC is cheap and abundant. Therefore, the addition of CMC 0.01 wt.% together with NSF 0.3 wt.% is also effective in preparing UBCWM with good fluidity and stability. (author)

  14. Late Cretaceous coal overlying karstic bauxite deposits in the Parnassus-Ghiona Unit, Central Greece: Coal characteristics and depositional environment

    Energy Technology Data Exchange (ETDEWEB)

    Kalaitzidis, Stavros; Siavalas, George; Christanis, Kimon [Dept. of Geology, University of Patras, 26504 Rio-Patras (Greece); Skarpelis, Nikos [Dept. of Geology and Geoenvironment, University of Athens, 15784 Zografou (Greece); Araujo, Carla Viviane [Petrobras-Cenpes GEOQ/PDEXP, Rua Horacio Macedo n 950, Cidade Universitaria - Ilha do Fundao, 21941-915 Rio de Janeiro (Brazil)

    2010-04-01

    The Pera-Lakkos coal located on top of bauxite deposits in the Ghiona mining district (Central Greece), is the only known Mesozoic (Late Cretaceous) coal in the country. It was derived from herbaceous plants and algae growing in mildly brackish mires that formed behind a barrier system during a regression of the sea, on a karstified limestone partly filled in with bauxitic detritus. Petrological, mineralogical and geochemical data point to the predominance of reducing conditions and intense organic matter degradation in the palaeomires. O/C vs. H/C and OI vs. HI plots, based on elemental analysis and Rock-Eval data, characterize kerogen types I/II. This reflects the relatively high liptinite content of the coal. Besides kerogen composition, O/C vs. H/C plot for the Pera-Lakkos coals is in accordance with a catagenesis stage of maturation in contrast with vitrinite reflectance and T{sub max} from Rock-Eval pyrolysis, which indicate the onset of oil window maturation stage. Suppression of vitrinite reflectance should be considered and the high liptinite content corroborates this hypothesis. Despite some favourable aspects for petroleum generation presented by the Pera-Lakkos coal, its maximum thickness (up to 50 cm) points to a restricted potential for petroleum generation. Coal oxidation took place either during the late stage of peat formation, due to wave action accompanying the subsequent marine transgression, or epigenetically after the emergence of the whole sequence due to percolation of drainage waters. Both options are also supported by the REE shale-normalized profiles, which demonstrate an upwards depletion in the coal layer. Oxidation also affected pyrite included in the coal; this led to the formation of acidic (sulfate-rich) solutions, which percolated downwards resulting in bleaching of the upper part of the underlying bauxite. (author)

  15. Study of Acoustic Emission and Mechanical Characteristics of Coal Samples under Different Loading Rates

    Directory of Open Access Journals (Sweden)

    Huamin Li

    2015-01-01

    Full Text Available To study the effect of loading rate on mechanical properties and acoustic emission characteristics of coal samples, collected from Sanjiaohe Colliery, the uniaxial compression tests are carried out under various levels of loading rates, including 0.001 mm/s, 0.002 mm/s, and 0.005 mm/s, respectively, using AE-win E1.86 acoustic emission instrument and RMT-150C rock mechanics test system. The results indicate that the loading rate has a strong impact on peak stress and peak strain of coal samples, but the effect of loading rate on elasticity modulus of coal samples is relatively small. When the loading rate increases from 0.001 mm/s to 0.002 mm/s, the peak stress increases from 22.67 MPa to 24.99 MPa, the incremental percentage is 10.23%, and under the same condition the peak strain increases from 0.006191 to 0.007411 and the incremental percentage is 19.71%. Similarly, when the loading rate increases from 0.002 mm/s to 0.005 mm/s, the peak stress increases from 24.99 MPa to 28.01 MPa, the incremental percentage is 12.08%, the peak strain increases from 0.007411 to 0.008203, and the incremental percentage is 10.69%. The relationship between acoustic emission and loading rate presents a positive correlation, and the negative correlation relation has been determined between acoustic emission cumulative counts and loading rate during the rupture process of coal samples.

  16. Coal Liquefaction characteristics and chemical structure of product oil; Sekitan ekika hanno tokusei to seiseibutsu no kagaku kozo

    Energy Technology Data Exchange (ETDEWEB)

    Endo, H.; Sato, M.; Chiba, T.; Hattori, H. [Hokkaido University, Sapporo (Japan). Center for Advanced Research of Energy Technology; Sasaki, M. [Hokkaido National Industrial Research Institute, Sapporo (Japan)

    1996-10-28

    Through the hydrogenolysis of Wandoan coal and Tanito Harum coal which are used for the NEDOL process, differences of liquefaction characteristics between them were found. The purpose of this study is to grasp these differences as differences of chemical structures of oil fractions. The compound type analysis was conducted for oil fractions obtained at varied reaction temperature for varied reaction time. Coal liquefaction characteristics of these coals were discussed by relating oil yields and chemical structures. For Tanito Harum coal, yields of gas and oil were considered to be lower than those for Wandoan coal, which reflected that the contents of partially hydrogenated hydroaromatics in oil fraction from the former were lower than those from the latter, and that the remarkable change of composition did not occur with the progress of the reaction. For both the coals, the remarkable changes in the average molecular weight of oil fraction were not observed with the progress of the reaction. While, the content of methane gradually increased with the progress of the reaction, which suggested that oil was gradually dealkylated. 5 figs.

  17. The carbon dioxide gasification characteristics of biomass char samples and their effect on coal gasification reactivity during co-gasification.

    Science.gov (United States)

    Mafu, Lihle D; Neomagus, Hein W J P; Everson, Raymond C; Okolo, Gregory N; Strydom, Christien A; Bunt, John R

    2018-06-01

    The carbon dioxide gasification characteristics of three biomass char samples and bituminous coal char were investigated in a thermogravimetric analyser in the temperature range of 850-950 °C. Char SB exhibited higher reactivities (R i , R s , R f ) than chars SW and HW. Coal char gasification reactivities were observed to be lower than those of the three biomass chars. Correlations between the char reactivities and char characteristics were highlighted. The addition of 10% biomass had no significant impact on the coal char gasification reactivity. However, 20 and 30% biomass additions resulted in increased coal char gasification rate. During co-gasification, chars HW and SW caused increased coal char gasification reactivity at lower conversions, while char SB resulted in increased gasification rates throughout the entire conversion range. Experimental data from biomass char gasification and biomass-coal char co-gasification were well described by the MRPM, while coal char gasification was better described by the RPM. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Influence of water-soaking time on the acoustic emission characteristics and spatial fractal dimensions of coal under uniaxial compression

    Directory of Open Access Journals (Sweden)

    Jia Zheqiang

    2017-01-01

    Full Text Available The water-soaking time affects the physical and mechanical properties of coals, and the temporal and spatial evolution of acoustic emissions reflects the fracture damage process of rock. This study conducted uniaxial compression acoustic emissions tests of coal samples with different water-soaking times to investigate the influence of water-soaking time on the acoustic emissions characteristics and spatial fractal dimensions during the deformation and failure process of coals. The results demonstrate that the acoustic emissions characteristics decrease with increases in the water-soaking time. The acoustic emissions spatial fractal dimension changes from a single dimensionality reduction model to a fluctuation dimensionality reduction model, and the stress level of the initial descending point of the fractal dimension increases. With increases in the water-soaking time, the destruction of coal transitions from continuous intense failure throughout the process to a lower release of energy concentrated near the peak strength.

  19. The importance of thermal behaviour and petrographic composition for understanding the characteristics of a Portuguese perhydrous Jurassic coal

    Energy Technology Data Exchange (ETDEWEB)

    Costa, A. [Centro de Geologia, Universidade do Porto (Portugal); Flores, D. [Centro de Geologia, Universidade do Porto (Portugal); Departamento de Geociencias, Ambiente e Ordenamento do Territorio, Faculdade de Ciencias, Universidade do Porto (Portugal); Suarez-Ruiz, I.; Pevida, C.; Rubiera, F. [Instituto Nacional del Carbon, (INCAR-CSIC), Oviedo (Spain); Iglesias, M.J. [Area de Quimica Organica, Universidad de Almeria (Spain)

    2010-12-01

    The perhydrous Batalha coal (Portugal) is found in the Cabacos and Montejunto Formation of the Oxfordian-Kimeridgian, Upper Jurassic age. From the macroscopic point of view, its appearance is similar to other perhydrous coals. Microscopically, the maceral group of huminite is the main organic component (96%), ulminite being the most important petrographic component, followed by textinite with resinite (4%) lumina filled. The huminite random reflectance is 0.33%. This coal is characterized by high H/C atomic ratio, and anomalous physical and chemical properties that are characteristic of perhydrous coals such as: (i) the absence of any correlation between reflectance and the chemical rank parameters; (ii) a lower real density than that of non-perhydrous coals; (iii) a high hydrogen content; and (iv) suppressed reflectance. Using its calorific value (moist, ash-free basis) as rank parameter, Batalha coal must be considered a subbituminous A coal. Hydrogen enrichment due to the presence of resinite has influenced the technological properties of this coal, namely: (i) reduction of the thermostability and decrease in the temperature of initial thermal decomposition due to, among other reasons, the existence of aliphatic structures with low dissociation energy bonds resulting from the presence of resinite; (ii) from the DTG profile, the volatile matter combustion and char combustion is not evident; (iii) development of chars made up of isotropic particles with angular edges, which is typical of a low rank coal; (iv) the evolution trend of gaseous compounds (CO, CO{sub 2} and CH{sub 4}) during pyrolysis; and, (v) an increase in its calorific value due to its hydrogen content. The study of this coal which is interbedded in Jurassic formations in the Lusitanian Basin of Portugal is a new contribution to the assessment of the evolution of organic matter in this area. (author)

  20. Organic geochemical investigation and coal-bed methane characteristics of the Guasare coals (Paso Diablo mine, western Venezuela)

    Science.gov (United States)

    Quintero, K.; Martinez, M.; Hackley, P.; Marquez, G.; Garban, G.; Esteves, I.; Escobar, M.

    2011-01-01

    The aim of this work was to carry out a geochemical study of channel samples collected from six coal beds in the Marcelina Formation (Zulia State, western Venezuela) and to determine experimentally the gas content of the coals from the Paso Diablo mine. Organic geochemical analyses by gas chromatography-mass spectrometry and isotopic analyses on-line in coalbed gas samples were performed. The results suggest that the Guasare coals were deposited in a continental environment under highly dysoxic and low salinity conditions. The non-detection of 18??(H)-oleanane does not preclude that the organic facies that gave rise to the coals were dominated by angiosperms. In addition, the presence of the sesquiterpenoid cadalene may indicate the subordinate contribution of gymnosperms (conifers) in the Paleocene Guasare mire. The average coalbed gas content obtained was 0.6 cm3/g. ??13C and D values indicate that thermogenic gas is prevalent in the studied coals. Copyright ?? Taylor & Francis Group, LLC.

  1. Characteristics of a bottomland hardwood forest under greentree reservoir management in East Central Arkansas

    Science.gov (United States)

    Michael R. Guttery; Andrew W. Ezell

    2006-01-01

    Greentree reservoirs are a viable option for creating habitat and hunting opportunities for migrating waterfowl. Unfortunately, the prolonged annual flooding often associated with greentree reservoir management can be highly detrimental to many of the desirable tree species in these stands. In the summer of 2004, a total of 327 plot centers were established in a...

  2. Pore system characteristics of the Permian transitional shale reservoir in the Lower Yangtze Region, China

    Directory of Open Access Journals (Sweden)

    Taotao Cao

    2016-10-01

    Full Text Available The Permian shale, a set of transitional shale reservoir, is considered to be an important shale gas exploration target in the Lower Yangtze region. Due to little research conducted on the pore system characteristic and its controlling factors of the shale gas reservoir, SEM, FE-SEM, low-pressure N2 adsorption, and mercury intrusion tests were carried out on the Permian shales from the outcrop and HC well in the southern Anhui. The results show that the Permian shales mainly consist of organic matter, quartz, illite, calcite, and pyrite, of which pyrite occurs as framboids coexisting with organic matter and the organic matter is distributed in shales in stripped, interstitial, thin film and shell shapes. The basic pore types are inorganic mineral pore (intercrystalline pore, intergranular edge pore, intergranular pore, and interlayer pore in clay minerals and the organic pore and microfracture, of which organic pore and microfracture are the dominating pore types. In shale, organic pores are not developed at all in some organic grains but are well developed in others, which may be related to the types of and maceral compositions of kerogen. Under tectonic stress, shale rocks could develop mylonitization phenomenon exhibiting organic grains well blend with clay minerals, and produce a mass of microfractures and nanopores between organic matter grains and clay minerals. Mercury intrusion tests show that the shale is mainly composed of micropore and transition pore with high porosity, good pore connectivity and high efficiency of mercury withdraw, while the shale that mainly dominated by mesopore and macropore has a low porosity, poor pore connectivity, and low efficiency of the mercury withdraw. The volume percentage of mesopore and marcopore is increasing with the increase of quartz, and that of micropore and transition pore has a decreased tendency along with the increase of soluble organic matter (S1. Organic matter is the main contributor to

  3. Temporal trends and spatial variation characteristics of primary air pollutants emissions from coal-fired industrial boilers in Beijing, China

    International Nuclear Information System (INIS)

    Xue, Yifeng; Tian, Hezhong; Yan, Jing; Zhou, Zhen; Wang, Junling; Nie, Lei; Pan, Tao; Zhou, Junrui; Hua, Shenbing; Wang, Yong; Wu, Xiaoqing

    2016-01-01

    Coal-fired combustion is recognized as a significant anthropogenic source of atmospheric compounds in Beijing, causing heavy air pollution events and associated deterioration in visibility. Obtaining an accurate understanding of the temporal trends and spatial variation characteristics of emissions from coal-fired industrial combustion is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, an integrated emission inventory of primary air pollutants emitted from coal-fired industrial boilers in Beijing is developed for the period of 2007–2013 using a technology-based approach. Future emission trends are projected through 2030 based on current energy-related and emission control policies. Our analysis shows that there is a general downward trend in primary air pollutants emissions because of the implementation of stricter local emission standards and the promotion by the Beijing municipal government of converting from coal-fired industrial boilers to gas-fired boilers. However, the ratio of coal consumed by industrial boilers to total coal consumption has been increasing, raising concerns about the further improvement of air quality in Beijing. Our estimates indicate that the total emissions of PM 10 , PM 2.5 , SO 2 , NO x , CO and VOCs from coal-fired industrial boilers in Beijing in 2013 are approximately 19,242 t, 13,345 t, 26,615 t, 22,965 t, 63,779 t and 1406 t, respectively. Under the current environmental policies and relevant energy savings and emission control plans, it may be possible to reduce NO x and other air pollutant emissions by 94% and 90% by 2030, respectively, if advanced flue gas purification technologies are implemented and coal is replaced with natural gas in the majority of existing boilers. - Highlights: • A unit-based emission inventory of coal-fired industrial boilers is developed. • Temporal trend of historical period 2007–2013 and the future till 2030 is

  4. The impact of anthropogenic pollution on limnological characteristics of a subtropical highland reservoir “Lago de Guadalupe”, Mexico

    Directory of Open Access Journals (Sweden)

    Sepulveda-Jauregui A.

    2013-08-01

    Full Text Available “Lago de Guadalupe” is an important freshwater ecosystem located in the northern part of the metropolitan area surrounding Mexico City, under high demographic pressure. It receives approximately 15 hm3·y-1 of untreated municipal wastewater from the surrounding municipalities. In order to develop a comparative assessment of the pollution effect over the limnological characteristics of Lago de Guadalupe, this lake was characterised from February 2006 to July 2009, and the results were compared with those obtained from a non-polluted lake “Lago el Llano” located in the same drainage area. Lago de Guadalupe was hypereutrophic with anoxic conditions throughout most of the water column. In contrast, Lago el Llano was mesotrophic with high dissolved oxygen concentrations throughout the entire water column with a clinograde profile. Both reservoirs had a monomictic mixing regime. The longitudinal zonation of physicochemical and biological variables were investigated in order to better understand the processes controlling the water quality across the reservoir during its residence time. This study shows the impact of anthropogenic pollution on the limnological characteristics of a subtropical reservoir and confirms that under adequate management schemes, namely avoiding pollution and wastewater discharges, subtropical reservoirs can be prevented from developing eutrophic conditions.

  5. Size Effect on Acoustic Emission Characteristics of Coal-Rock Damage Evolution

    OpenAIRE

    Wen, Zhijie; Wang, Xiao; Chen, Lianjun; Lin, Guan; Zhang, Hualei

    2017-01-01

    Coal-gas outburst, rock burst, and other mine dynamic disasters are closely related to the instability and failure of coal-rock. Coal-rock is the assemblies of mineral particles of varying sizes and shapes bonded together by cementing materials. The damage and rupture process of coal-rock is accompanied by acoustic emission (AE), which can be used as an effective means to monitor and predict the instability of coal-rock body. In this manuscript, considering the size effect of coal-rock, the i...

  6. Combustion characteristics of intensively cleaned coal fractions. Effect of mineral matter

    Energy Technology Data Exchange (ETDEWEB)

    Rubiera, F.; Arenillas, A.; Fuente, E.; Pis, J.J. [Inst. Nacional de Carbon, Oviedo (Spain); Ivatt, S. [ETSU, Harwell, Didcot (United Kingdom)

    1997-12-31

    The purpose of this work has been to assess the effect that intensive coal cleaning exerts on the combustion behaviour of different density-separated coal fractions. Samples with ash contents varying from 39% for the raw coal, to 2% for the cleanest fraction were obtained after density separation. Temperature-programmed combustion and isothermal gasification in air were used to measure the reactivities of the parent coal and the cleaned fractions. Coal and char reactivities increased with increasing ash content of the samples. Thermal analysis-mass spectrometry of the low-temperature ashes was also carried out in order to study the reactions of coal minerals under combustion conditions. (orig.)

  7. Analysis of the relationship between the coal properties and their liquefaction characteristics by using the coal data base; Tanshu data base ni yoru tanshitsu to ekika tokusei no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Kanbayashi, Y.; Okada, K. [Coal Mining Research Center, Tokyo (Japan)

    1996-10-28

    The relationship between coal properties and liquefaction or gasification characteristics was analyzed by using the analysis and test results and liquefaction characteristics in the coal data base. On liquefaction reaction, the close relation between an oil yield and coal constituent composition or a coal rank is well-known. Various multivariable regression analyses were conducted by using 6 factors as variables such as calorific value, volatile component, O/C and H/C atomic ratios, exinite+vitrinite content and vitrinite reflectance, and liquefaction characteristics as variate. On liquefaction characteristics, the oil yield of dehydrated and deashed coals, asphaltene yield, hydrogen consumption, produced water and gas quantities, and oil+asphaltene yield were predicted. The theoretical gasification efficiency of each specimen was calculated to evaluate the liquefaction reaction obtained. As a result, the oil yield increased with H/C atomic ratio, while the theoretical gasification efficiency increased with O/C atomic ratio. 5 figs., 1 tab.

  8. Characteristics of phytoplankton in Lake Karachay, a storage reservoir of medium-level radioactive waste.

    Science.gov (United States)

    Atamanyuk, Natalia I; Osipov, Denis I; Tryapitsina, Galina A; Deryabina, Larisa V; Stukalov, Pavel M; Ivanov, Ivan A; Pryakhin, Evgeny A

    2012-07-01

    The status of the phytoplankton community in Lake Karachay, a storage reservoir of liquid medium-level radioactive waste from the Mayak Production Association, Chelyabinsk Region, Russia, is reviewed. In 2010, the concentration of Sr in water of this reservoir was found to be 6.5 × 10(6) Bq L, the concentration of 137Cs was 1.6 × 10(7) Bq L, and total alpha activity amounted to 3.0 × 10(3) Bq L. An increased level of nitrates was observed in the reservoir-4.4 g L. It has been demonstrated that in this reservoir under the conditions of the maximum contamination levels known for aquatic ecosystems in the entire biosphere, a phytoplankton community exists that has a pronounced decline in species diversity, almost to the extent of a monoculture of widely-spread thread eurytopic cyanobacteria Geitlerinema amphibium.

  9. Sedimentological reservoir characteristics of the Paleocene fluvial/lacustrine Yabus Sandstone, Melut Basin, Sudan

    Science.gov (United States)

    Mahgoub, M. I.; Padmanabhan, E.; Abdullatif, O. M.

    2016-11-01

    Melut Basin in Sudan is regionally linked to the Mesozoic-Cenozoic Central and Western African Rift System (CWARS). The Paleocene Yabus Formation is the main oil producing reservoir in the basin. It is dominated by channel sandstone and shales deposited in fluvial/lacustrine environment during the third phase of rifting in the basin. Different scales of sedimentological heterogeneities influenced reservoir quality and architecture. The cores and well logs analyses revealed seven lithofacies representing fluvial, deltaic and lacustrine depositional environments. The sandstone is medium to coarse-grained, poorly to moderately-sorted and sub-angular to sub-rounded, arkosic-subarkosic to sublitharenite. On the basin scale, the Yabus Formation showed variation in sandstone bodies, thickness, geometry and architecture. On macro-scale, reservoir quality varies vertically and laterally within Yabus Sandstone where it shows progressive fining upward tendencies with different degrees of connectivity. The lower part of the reservoir showed well-connected and amalgamated sandstone bodies, the middle to the upper parts, however, have moderate to low sandstone bodies' connectivity and amalgamation. On micro-scale, sandstone reservoir quality is directly affected by textures and diagenetic changes such as compaction, cementation, alteration, dissolution and kaolinite clays pore fill and coat all have significantly reduced the reservoir porosity and permeability. The estimated porosity in Yabus Formation ranges from 2 to 20% with an average of 12%; while permeability varies from 200 to 500 mD and up to 1 Darcy. The understanding of different scales of sedimentological reservoir heterogeneities might contribute to better reservoir quality prediction, architecture, consequently enhancing development and productivity.

  10. Mechanical characteristics of fully mechanized top-coal caving face and surrounding rock stress shell

    Energy Technology Data Exchange (ETDEWEB)

    Xie Guang-xiang [Anhui University of Science and Technology, Huainan (China)

    2005-06-15

    The distribution of surrounding rock stress in fully mechanized top-coal caving (FMTC) face was fully researched by large-scale and non-linear three-dimensional numerical simulation and equivalent laboratory. The results show that, there is the structure that is made of macroscopical stress shell composed of high stress binds in overlying strata of FMTC face. Stress shell, which bears and pass load of overlying strata, is primary supporting body. The stress in skewback of stress shell forms abutment pressure of surrounding rock in vicinity of working face. Bond-beam structure lies in reducing zone under stress shell. It only bear partial burden of strata under stress shell. The uppermost mechanical characteristic of FMTC face is lying in the low stress area under stress shell. It is the essential cause of strata behaviors of FMTC face relaxation. On the basis of analyzing stress shell, the mechanical essence that top coal performs a function of bedding is demonstrated. 4 refs., 7 figs.

  11. Characteristics of the Roof Behaviors and Mine Pressure Manifestations During the Mining of Steep Coal Seam

    Science.gov (United States)

    Hong-Sheng, Tu; Shi-Hao, Tu; Cun, Zhang; Lei, Zhang; Xiao-Gang, Zhang

    2017-12-01

    A steep seam similar simulation system was developed based on the geological conditions of a steep coal seam in the Xintie Coal Mine. Basing on similar simulation, together with theoretical analysis and field measurement, an in-depth study was conducted to characterize the fracture and stability of the roof of steep working face and calculate the width of the region backfilled with gangue in the goaf. The results showed that, as mining progressed, the immediate roof of the steep face fell upon the goaf and backfilled its lower part due to gravity. As a result, the roof in the lower part had higher stability than the roof in the upper part of the working face. The deformation and fracture of main roof mainly occurred in the upper part of the working face; the fractured main roof then formed a "voussoir beam" structure in the strata's dip direction, which was subjected to the slip- and deformation-induced instability. The stability analysis indicated that, when the dip angle increased, the rock masses had greater capacity to withstand slip-induced instability but smaller capacity to withstand deformation-induced instability. Finally, the field measurement of the forces exerted on the hydraulic supports proved the characteristics of the roof's behaviors during the mining of a steep seam.

  12. Material Properties and Characteristics for Development of an Expert System for Coal-Tar Sealers

    National Research Council Canada - National Science Library

    Shoenberger, James

    2001-01-01

    .... Several coal-tar mixtures that varied with source of the coal-tar emulsion, amount of aggregate, and amount of polymer used in the mixtures were evaluated for their field performance and material properties...

  13. The experimental modeling of gas percolation mechanisms in a coal-measure tight sandstone reservoir: A case study on the coal-measure tight sandstone gas in the Upper Triassic Xujiahe Formation, Sichuan Basin, China

    Directory of Open Access Journals (Sweden)

    Shizhen Tao

    2016-12-01

    Full Text Available Tight sandstone gas from coal-measure source rock is widespread in China, and it is represented by the Xujiahe Formation of the Sichuan Basin and the Upper Paleozoic of the Ordos Basin. It is affected by planar evaporative hydrocarbon expulsion of coal-measure source rock and the gentle structural background; hydrodynamics and buoyancy play a limited role in the gas migration-accumulation in tight sandstone. Under the conditions of low permeability and speed, non-Darcy flow is quite apparent, it gives rise to gas-water mixed gas zone. In the gas displacing water experiment, the shape of percolation flow curve is mainly influenced by core permeability. The lower the permeability, the higher the starting pressure gradient as well as the more evident the non-Darcy phenomenon will be. In the gas displacing water experiment of tight sandstone, the maximum gas saturation of the core is generally less than 50% (ranging from 30% to 40% and averaging at 38%; it is similar to the actual gas saturation of the gas zone in the subsurface core. The gas saturation and permeability of the core have a logarithm correlation with a correlation coefficient of 0.8915. In the single-phase flow of tight sandstone gas, low-velocity non-Darcy percolation is apparent; the initial flow velocity (Vd exists due to the slippage effect of gas flow. The shape of percolation flow curve of a single-phase gas is primarily controlled by core permeability and confining pressure; the lower the permeability or the higher the confining pressure, the higher the starting pressure (0.02–0.08 MPa/cm, whereas, the higher the quasi-initial flow speed, the longer the nonlinear section and the more obvious the non-Darcy flow will be. The tight sandstone gas seepage mechanism study shows that the lower the reservoir permeability, the higher the starting pressure and the slower the flow velocity will be, this results in the low efficiency of natural gas migration and accumulation as well as

  14. Spatiotemporal associations of reservoir nutrient characteristics and the invasive, harmful alga Prymnesium parvum in West Texas

    Science.gov (United States)

    VanLandeghem, Matthew M.; Farooqi, Mukhtar; Southard, Greg M.; Patino, Reynaldo

    2015-01-01

    Golden alga (Prymnesium parvum) is a harmful alga that has caused ecological and economic harm in freshwater and marine systems worldwide. In inland systems of North America, toxic blooms have nearly eliminated fish populations in some systems. Modifying nutrient profiles through alterations to land or water use may be a viable alternative for golden alga control in reservoirs. The main objective of this study was to improve our understanding of the nutrient dynamics that influence golden alga bloom formation and toxicity in west Texas reservoirs. We examined eight sites in the Upper Colorado River basin, Texas: three impacted reservoirs that have experienced repeated golden alga blooms; two reference reservoirs where golden alga is present but nontoxic; and three confluence sites downstream of the impacted and reference sites. Total, inorganic, and organic nitrogen and phosphorus and their ratios were quantified monthly along with golden alga abundance and ichthyotoxicity between December 2010 and July 2011. Blooms persisted for several months at the impacted sites, which were characterized by high organic nitrogen and low inorganic nitrogen. At impacted sites, abundance was positively associated with inorganic phosphorus and bloom termination coincided with increases in inorganic nitrogen and decreases in inorganic phosphorus in late spring. Management of both inorganic and organic forms of nutrients may create conditions in reservoirs unfavorable to golden alga.

  15. Laboratory and simulation approach to the polymer EOR evaluation in German reservoir characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, S.; Hincapie-Reina, R.; Ganzer, L. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE

    2013-08-01

    Nowadays, polymer flooding is widely used as it enhances oil recovery. As polymer has relatively higher viscosity than water, which leads to better mobility ratio compared to it, and thus better sweep efficiency. However, this technique is limited by some factors. As normal polymers are not tolerant to high temperature or salinity or hardness, which lead to lose of most their viscosity, and thus lost their function in enhanced oil recovery. Therefore, new polymers which are resistant to high temperature, high salinity or other factors which may happen in the reservoir should be employed. In that direction, the present work focus in characterize two different polymers, Flopaam AN 125 and ZLPAM 22051, how they would be influenced by polymer concentration, salinity, shear rate and temperature, and to predict how they would work in the reservoir. A synthetic brine from a German reservoir (Valendis, Suderbruch Field) is used to analyze the polymer. In many different previous experiments is observed the divalent and monovalent effect of salt in polymers was carried out. Rheology characterization was done under the reservoir conditions to get the best approximation related to concentration, shear rate and temperature effect; filtration ratio and filterability plot are used as a quality check for the solutions. Finally, all the data is used into the Polymer Flood Predictive Model (PFPM), to figure out how polymer acted in German typical reservoir conditions, and the specific incremental in oil recovery and effect due the possible polymer application, which might provide information for future polymer flooding application decisions. (orig.)

  16. Characteristics of process oils from HTI coal/plastics co-liquefaction runs

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, G.A.; Brandes, S.D.; Winschel, R.A. [and others

    1995-12-31

    The objective of this project is to provide timely analytical support to DOE`s liquefaction development effort. Specific objectives of the work reported here are presented. During a few operating periods of Run POC-2, HTI co-liquefied mixed plastics with coal, and tire rubber with coal. Although steady-state operation was not achieved during these brief tests periods, the results indicated that a liquefaction plant could operate with these waste materials as feedstocks. CONSOL analyzed 65 process stream samples from coal-only and coal/waste portions of the run. Some results obtained from characterization of samples from Run POC-2 coal/plastics operation are presented.

  17. Drying kinetics characteristic of Indonesia lignite coal (IBC) using lab scale fixed bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kang, TaeJin; Jeon, DoMan; Namkung, Hueon; Jang, DongHa; Jeon, Youngshin; Kim, Hyungtaek [Ajou Univ., Suwon (Korea, Republic of). Div. of Energy Systems Research

    2013-07-01

    Recent instability of energy market arouse a lot of interest about coal which has a tremendous amount of proven coal reserves worldwide. South Korea hold the second rank by importing 80 million tons of coal in 2007 following by Japan. Among various coals, there is disused coal. It's called Low Rank Coal (LRC). Drying process has to be preceded before being utilized as power plant. In this study, drying kinetics of LRC is induced by using a fixed bed reactor. The drying kinetics was deduced from particle size, the inlet gas temperature, the drying time, the gas velocity, and the L/D ratio. The consideration on Reynold's number was taken for correction of gas velocity, particle size, and the L/D ratio was taken for correction packing height of coal. It can be found that active drying of free water and phase boundary reaction is suitable mechanism through the fixed bed reactor experiments.

  18. [The spectrum studies of structure characteristics in magma contact metamorphic coal].

    Science.gov (United States)

    Wu, Dun; Sun, Ruo-Yu; Liu, Gui-Jian; Yuan, Zi-Jiao

    2013-10-01

    The structural parameters evolution of coal due to the influence of intrusions of hot magma was investigated and analyzed. X-ray diffraction and laser confocal microscope Raman spectroscopy were used to test and analyze 4 coal samples undergoing varying contact-metamorphism by igneous magmas in borehole No. 13-4 of Zhuji coal mine, Huainan coalfield. The result showed that coal XRD spectrum showed higher background intensity, with the 26 degrees and 42 degrees nearby apparent graphite diffraction peak. Two significant vibration peaks of coal Raman spectra were observed in the 1 000-2 000 cm(-1) frequency range: broad "D" peak at 1 328-1 369 cm(-1) and sharp "G" peak at 1 564-1 599 cm(-1). With the influence of magma intrusion, the relationship between coal structural parameters and coal ranks was excellent.

  19. [Absorption Characteristics of Particulates and CDOM in Waters of Chagan Lake and Xinlicheng Reservoir in Autumn].

    Science.gov (United States)

    Li, Si-jia; Song, Kai-shan; Zhao, Ying; Mu, Guang-yi; Shao, Tian-tian; Ma, Jian-hang

    2016-01-15

    Field surveys and laboratory analysis were carried out in Chagan Lake and Xinlicheng Reservoir under different salinity conditions in September 2012. In the laboratory, the absorption coefficients of particulates and chromophoric dissolved organic matter (CDOM) were measured, aiming to compare the absorption features, source of optical active substances and relative contribution of optical active constituents over the range of PAR (400-700 nm) in Chagan Lake and Xinlicheng Reservoir. The results showed that the Chagan Lake and Xinlicheng Reservoir were water bodies with medium eutrophication in autumn by TAL nutrient index and the absorption spectra of particulates matters were similar to those of phytoplankton. For the Chagan Lake with high salinity( EC = 988. 87 micro S x cm(-1)), the total particulate absorption was dominated by the nonalgal particles, and the contribution rate was in the order of nonalgal particles > phytoplankton > CDOM. For the Xinlicheng Reservoir with low salinity (EC = 311.67 microS x -cm(-1)), the total particulate absorption was dominated by the phytoplankton, and the contribution rate was ranked as phytoplankton > nonalgal particles > CDOM. Positive correlation was observed between a(p) (440), a(p) (675), a(d) (440) and total suspended matter (TSM), inorganic suspended matter (ISM), organic suspended matter (OSM) and Chl-a respectively in Chagan Lake, with correlation coefficients all above 0.55. Positive correlation was observed between a(p)(440), a(p) (675) and Chl-a (0.77 and 0.85, P CDOM in the Chagan Lake was less than that in the Xinlicheng Reservoir. The Chagan Lake was greatly affected by wind speed and shore collapse to produce suspended mineral and sediment particles. Thereby the total particulate absorption was dominated by the nonalgal particles. The waters in the Xinlicheng Reservoir were greatly impacted by terrestrial inorganic matter, and the growth of phytoplankton was weakened and microbes activities were strengthened

  20. Hydrochemical characteristics and quality assessment of deep groundwater from the coal-bearing aquifer of the Linhuan coal-mining district, Northern Anhui Province, China.

    Science.gov (United States)

    Lin, Man-Li; Peng, Wei-Hua; Gui, He-Rong

    2016-04-01

    There is little information available about the hydrochemical characteristics of deep groundwater in the Linhuan coal-mining district, Northern Anhui Province, China. In this study, we report information about the physicochemical parameters, major ions, and heavy metals of 17 groundwater samples that were collected from the coal-bearing aquifer. The results show that the concentrations of total dissolved solids, electrical conductivity, and potassium and sodium (K(+) + Na(+)) in most of the groundwater samples exceeded the guidelines of the World Health Organization (WHO) and the Chinese National Standards for Drinking Water Quality (GB 5749-2006). The groundwater from the coal-bearing aquifer was dominated by the HCO3·Cl-K + Na and HCO3·SO4-K + Na types. Analysis with a Gibbs plot suggested that the major ion chemistry of the groundwater was primarily controlled by weathering of rocks and that the coal-bearing aquifer in the Linhuan coal-mining district was a relatively closed system. K(+) and Na(+) originated from halite and silicate weathering reactions, while Ca(2+) and Mg(2+) originated from the dissolution of calcite, dolomite, and gypsum or anhydrite. Ion exchange reactions also had an influence on the formation of major ions in groundwater. The concentrations of selected heavy metals decreased in the order Mn > Zn > Cr > Cu > Ni > Pb. In general, the heavy metal concentrations were low; however, the Cr, Mn, and Ni concentrations in some of the groundwater samples exceeded the standards outlined by the WHO, the GB 5749-2006, and the Chinese National Standards for Groundwater (GB/T 14848-93). Analysis by various indices (% Na, SAR, and EC), a USSL diagram, and a Wilcox diagram showed that both the salinity and alkalinity of the groundwater were high, such that the groundwater could not be used for irrigating agricultural land without treatment. These results will be significant for water resource exploiting and utilization in

  1. Free radical reaction characteristics of coal low-temperature oxidation and its inhibition method.

    Science.gov (United States)

    Li, Zenghua; Kong, Biao; Wei, Aizhu; Yang, Yongliang; Zhou, Yinbo; Zhang, Lanzhun

    2016-12-01

    Study on the mechanism of coal spontaneous combustion is significant for controlling fire disasters due to coal spontaneous combustion. The free radical reactions can explain the chemical process of coal at low-temperature oxidation. Electron spin resonance (ESR) spectroscopy was used to measure the change rules of the different sorts and different granularity of coal directly; ESR spectroscopy chart of free radicals following the changes of temperatures was compared by the coal samples applying air and blowing nitrogen, original coal samples, dry coal samples, and demineralized coal samples. The fragmentation process was the key factor of producing and initiating free radical reactions. Oxygen, moisture, and mineral accelerated the free radical reactions. Combination of the free radical reaction mechanism, the mechanical fragmentation leaded to the elevated CO concentration, fracturing of coal pillar was more prone to spontaneous combustion, and spontaneous combustion in goaf accounted for a large proportion of the fire in the mine were explained. The method of added diphenylamine can inhibit the self-oxidation of coal effectively, the action mechanism of diphenylamine was analyzed by free radical chain reaction, and this research can offer new method for the development of new flame retardant.

  2. A study of relations between physicochemical properties of crude oils and microbiological characteristics of reservoir microflora

    Science.gov (United States)

    Yashchenko, I. G.; Polishchuk, Yu. M.; Peremitina, T. O.

    2015-10-01

    The dependence of the population and activity of reservoir microflora upon the chemical composition and viscosity of crude oils has been investigated, since it allows the problem of improvement in the technologies and enhancement of oil recovery as applied to production of difficult types of oils with anomalous properties (viscous, heavy, waxy, high resin) to be solved. The effect of the chemical composition of the oil on the number, distribution, and activity of reservoir microflora has been studied using data on the microbiological properties of reservoir water of 16 different fields in oil and gas basins of Russia, Mongolia, China, and Vietnam. Information on the physicochemical properties of crude oils of these fields has been obtained from the database created at the Institute of Petroleum Chemistry, Siberian Branch on the physicochemical properties of oils throughout the world. It has been found that formation water in viscous oil reservoirs is char acterized by a large population of heterotrophic and sulfate reducing bacteria and the water of oil fields with a high paraffin content, by population of denitrifying bacteria.

  3. Characteristic fracture spacing in primary and secondary recovery for naturally fractured reservoirs

    NARCIS (Netherlands)

    Gong, J.; Rossen, W.R.

    2018-01-01

    If the aperture distribution is broad enough in a naturally fractured reservoir, even one where the fracture network is highly inter-connected, most fractures can be eliminated without significantly affecting the flow through the fracture network. During a waterflood or enhanced-oil-recovery

  4. Combined geophysical, geochemical and geological investigations of geothermal reservoir characteristics in Lower Saxony, Germany

    Science.gov (United States)

    Hahne, B.; Thomas, R.

    2012-04-01

    The North German basin provides a significant geothermal potential, although temperature gradients are moderate. However, deep drilling up to several thousand meters is required to reach temperatures high enough for efficient generation of geothermal heat and electric power. In these depths we have not much information yet about relevant physical properties like porosity or permeability of the rock formations. Therefore the costs of developing a geothermal reservoir and the risk of missing the optimum drilling location are high. The collaborative research association "Geothermal Energy and High Performance Drilling" (gebo) unites several universities and research institutes in Lower Saxony, Germany. It aims at a significant increase of economic efficiency by introducing innovative technology and high tech materials resisting temperatures up to 200 °C in the drilling process. Furthermore, a better understanding of the geothermal reservoir is essential. gebo is structured into four main fields: Drilling Technology, Materials, Technical Systems and Geosystem. Here, we show the combined work of the Geosystem group, which focuses on the exploration of geological fault zones as a potential geothermal reservoir as well as on modeling the stress field, heat transport, coupled thermo-hydro-mechanical processes, geochemical interactions and prediction of the long-term behavior of the reservoir. First results include combined seismic and geoelectric images of the Leinetalgraben fault system, a comparison of seismic images from P- and S-wave measurements, mechanical properties of North German rocks from field and laboratory measurements as well as from drill cores, seismological characterization of stimulated reservoirs, a thermodynamic "gebo" database for modeling hydrogeochemical processes in North German formation waters with high salinity and at high temperatures, stress models for specific sites in northern Germany, and modeling results of permeability and heat transport

  5. Fouling deposition characteristic by variation of coal particle size and deposition temperature in DTF (Drop Tube Furnace)

    Energy Technology Data Exchange (ETDEWEB)

    Namkung, Hueon; Jeon, Youngshin; Kim, Hyungtaek [Ajou Univ., Suwon (Korea, Republic of). Div. of Energy Systems Research; Xu, Li-hua [IAE, Suwon (Korea, Republic of). Plant Engineering Center

    2013-07-01

    One of the major operation obstacles in gasification process is ash deposition phenomenon. In this investigation, experiment was carried out to examine coal fouling characteristics using a laminar DTF (Drop Tube Furnace) with variation of operating condition such as different coal size, and probe surface temperature. Four different samples of pulverized coal were injected into DTF under various conditions. The ash particles are deposited on probe by impacting and agglomerating action. Fouling grains are made of eutectic compound, which is made by reacting with acid minerals and alkali minerals, in EPMA (Electron Probe Micro-Analysis). And agglomeration area of fouling at top layer is wide more than it of middle and bottom layer. The major mineral factors of fouling phenomenon are Fe, Ca, and Mg. The deposition quantity of fouling increases with increasing particle size, high alkali mineral (Fe, Ca, and Mg) contents, and ash deposition temperature.

  6. Experimental study on the gasification characteristics of coal and orimulsion in 0.5 T/D gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ho Young; Kim, Jong Young; An, Dal Hong; Park, Tae Jun [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

    1995-12-31

    For the construction of commercial plant for IGCC imported from aboard in near future, it is aimed to get gasification data, practice the gasification design capability, and develop a fundamental key technology through the experiments for different kinds of coals (Datong, Roto, Alaska) by 0.5 T/D gasifier. We performed the experiments for physical properties and reactivities on selected coals by means of Drop Tube Reactor, numerical analysis for the reactor. Throughout the characteristic studies of orimulsion gasification, feasibility studies for orimulsion gasification as a fuel for power plant be performed. With the six experiment runs for the coal gasifier, several problems were found to remedy. After remedies, the gasifier could run at good operating conditions maintaining with 200% design feed rate over 1200-1550 degree. The third and fourth gasification runs with Roto were satisfactorily completed, during which gross heating values from produced gas were 7200-8200 Kcal/Nm{sup 3}. (author). 118 refs., 145 figs.

  7. Experimental study on the gasification characteristics of coal and orimulsion in 0.5 T/D gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ho Young; Kim, Jong Young; An, Dal Hong; Park, Tae Jun [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

    1996-12-31

    For the construction of commercial plant for IGCC imported from aboard in near future, it is aimed to get gasification data, practice the gasification design capability, and develop a fundamental key technology through the experiments for different kinds of coals (Datong, Roto, Alaska) by 0.5 T/D gasifier. We performed the experiments for physical properties and reactivities on selected coals by means of Drop Tube Reactor, numerical analysis for the reactor. Throughout the characteristic studies of orimulsion gasification, feasibility studies for orimulsion gasification as a fuel for power plant be performed. With the six experiment runs for the coal gasifier, several problems were found to remedy. After remedies, the gasifier could run at good operating conditions maintaining with 200% design feed rate over 1200-1550 degree. The third and fourth gasification runs with Roto were satisfactorily completed, during which gross heating values from produced gas were 7200-8200 Kcal/Nm{sup 3}. (author). 118 refs., 145 figs.

  8. Numerical investigation of heat transfer characteristics in utility boilers of oxy-coal combustion

    International Nuclear Information System (INIS)

    Hu, Yukun; Li, Hailong; Yan, Jinyue

    2014-01-01

    Highlights: • Air-coal and oxy-coal combustion in an industrial scale PF boiler were simulated in ANSYS FLUENT. • The O 2 concentration of 33 vol% in the oxy-coal combustion case matches the air-coal combustion case most closely. • The moisture in the flue gas has little impact on flame temperature, but positive impact on surface incident radiation. - Abstract: Oxy-coal combustion has different flue gas composition from the conventional air-coal combustion. The different composition further results in different properties, such as the absorption coefficient, emissivity, and density, which can directly affect the heat transfer in both radiation and convection zones of utility boilers. This paper numerically studied a utility boiler of oxy-coal combustion and compares with air-coal combustion in terms of flame profile and heat transferred through boiler side walls in order to understand the effects of different operating conditions on oxy-coal boiler retrofitting and design. Based on the results, it was found that around 33 vol% of effective O 2 concentration ([O 2 ] effective ) the highest flame temperature and total heat transferred through boiler side walls in the oxy-coal combustion case match to those in the air-coal combustion case most; therefore, the 33 vol% of [O 2 ] effective could result in the minimal change for the oxy-coal combustion retrofitting of the existing boiler. In addition, the increase of the moisture content in the flue gas has little impact on the flame temperature, but results in a higher surface incident radiation on boiler side walls. The area of heat exchangers in the boiler was also investigated regarding retrofitting. If boiler operates under a higher [O 2 ] effective , to rebalance the load of each heat exchanger in the boiler, the feed water temperature after economizer can be reduced or part of superheating surfaces can be moved into the radiation zone to replace part of the evaporators

  9. Studies on characteristics of fluid dynamics in the coal liquefaction reactor; Sekitan ekika hanno tonai no ryudo tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Sakawaki, K.; Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan); Mochizuki, M.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Tachikawa, N.; Moki, T.; Ishikawa, I. [Japan Atomic Energy Research Institute, Tokyo (Japan)

    1996-10-28

    To design the coal liquefaction reactor of large scale plant in future, it is important to understand characteristics of fluid dynamics within the coal liquefaction reactor. In this study, to measure the fluid dynamics of liquid phase within the coal liquefaction reactor operated under high temperature and high pressure coal liquefaction condition, neutron attenuating tracer (NAT) technique, one of the tracer test methods, was applied using 1 t/d coal treating PSU. The residence time of liquid phase within the reactor can be measured by utilizing property of neutron of being absorbed by materials. The tracer was injected at the inlets of first and third reactors, and the neutron was counted at each outlet. The concentration of tracer was derived from the discrete value, to determine the residence time distribution of liquid phase. The mean residence time of liquid phase in the single first reactor and in the total three reactors were prolonged under the severe operation conditions of liquefaction. The more severe the liquefaction operation condition was, the more active the mixing of liquid phase was in the first reactor. It was found that the progress of reaction was accelerated. 2 refs., 5 figs., 1 tab.

  10. Energy characteristics of finest coal particles surfaces versus their upgrading using flotation

    Energy Technology Data Exchange (ETDEWEB)

    Jerzy Sablik

    2007-07-01

    The paper presents selected results of investigations on energy properties of the fine coal particles, and methodological grounds for conducting such investigations. Using the discussed relationships, values of contact angle of coal particles with various degree of coalification in the range defined by the energy nonhomogeneity of the surfaces were computed. There have been determined the values of the contact angles of coal particles with hydrophobic and hydrophilic surfaces after coating with nonpolar and polar reagents. The energy state of the surfaces of coal particles in the feeds and products of industrial flotation were determined, which enabled to evaluate this process. 22 refs., 6 figs., 4 tabs.

  11. Structural characteristics and gasification reactivity of chars prepared from K{sub 2}CO{sub 3} mixed HyperCoals and coals

    Energy Technology Data Exchange (ETDEWEB)

    Atul Sharma; Hiroyuki Kawashima; Ikuo Saito; Toshimasa Takanohashi [National Institute of Advanced Industrial Science and Technology, Ibaraki (Japan). Advanced Fuel Group

    2009-04-15

    HyperCoal is a clean coal with mineral matter content <0.05 wt %. Oaky Creek (C = 82%), and Pasir (C = 68%) coals were subjected to solvent extraction method to prepare Oaky Creek HyperCoal, and Pasir HyperCoal. Experiments were carried out to compare the gasification reactivity of HyperCoals and parent raw coals with 20, 40, 50 and 60% K{sub 2}CO{sub 3} as a catalyst at 600, 650, 700, and 775{sup o}C with steam. Gasification rates of coals and HyperCoals were strongly influenced by the temperature and catalyst loading. Catalytic steam gasification of HyperCoal chars was found to be chemical reaction controlled in the 600-700{sup o}C temperature range for all catalyst loadings. Gasification rates of HyperCoal chars were found to be always higher than parent coals at any given temperature for all catalyst loadings. However, X-ray diffraction results showed that the microstructures of chars prepared from coals and HyperCoals were similar. Results from nuclear magnetic resonance spectroscopy show no significant difference between the chemical compositions of the chars. Significant differences were observed from scanning electron microscopy images, which showed that the chars from HyperCoals had coral-reef like structures whereas dense chars were observed for coals. 26 refs., 8 figs., 2 tabs.

  12. MEOR (microbial enhanced oil recovery) data base and evaluation of reservoir characteristics for MEOR projects

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, R.S.

    1989-09-01

    One aspect of NIPER's microbial enhanced oil recovery (MEOR) research program has been focused on obtaining all available information regarding the use of microorganisms in enhanced oil recovery field projects. The data have been evaluated in order to construct a data base of MEOR field projects. The data base has been used in this report to present a list of revised reservoir screening criteria for MEOR field processes. This list is by no means complete; however, until more information is available from ongoing field tests, it represents the best available data to date. The data base has been studied in this report in order to determine any significant reports from MEOR field projects where the microbial treatment was unsuccessful. Such information could indicate limitations of MEOR processes. The types of reservoir information sought from these projects that could be limitations of microorganisms include reservoir permeability, salinity, temperature, and high concentrations of minerals in the rock such as selenium, arsenic, or mercury. Unfortunately, most of the MEOR field projects to date have not reported this type of information; thus we still cannot assess field limitations until more projects report these data. 7 refs., 1 fig., 7 tabs.

  13. Main characteristics of the radioactive enrichment in ashes produced in coal-fired power stations

    International Nuclear Information System (INIS)

    Baeza, Antonio; Corbacho, Jose A.; Cancio, David; Robles, Beatriz; Mora, Juan C.

    2008-01-01

    Under contract with the Spain's 'Nuclear Safety Council', a study is being conducted of the nation's largest nominal output coal-fired power stations. Its purpose is to assess the radiological impact on workers and local populations due to this source of NORM activity. One of the aspects of particular interest is the study of the radioactive enrichment in the combustion wastes relative to the different coals used as fuel (usually local bituminous coal or lignite, or imported coal). These wastes consist of fly ash (mostly fine particles collected in electrostatic precipitators), and bottom ash (larger in size, and collected wet or dry in hoppers below the boilers). In general terms, the enrichment factors measured were between 2 and 18 for the radionuclides 40 K, 226 Ra, 232 Th, and 210 Po. The magnitude of this enrichment factor depended mainly on the ash content of each coal, and hence on the type of coal used as fuel and the specific operation cycle in the different power stations. For the radionuclides 40 K, 226 Ra, and 232 Th, the enrichment was relatively similar in value in the fly and bottom ashes produced by the different types of coal used in the power stations studied. For 210 Po, however, as was expected, the enrichment was much greater in the fly ash than in the bottom ash for each coal analyzed. (author)

  14. Effect of organic calcium compounds on combustion characteristics of rice husk, sewage sludge, and bituminous coal: thermogravimetric investigation.

    Science.gov (United States)

    Zhang, Lihui; Duan, Feng; Huang, Yaji

    2015-04-01

    Experiments were conducted in a thermogravimetric analyzer to assess the enhancement of combustion characteristics of different solid fuels blended with organic calcium compounds (OCCs). Rice husk, sewage sludge, and bituminous coal, and two OCC were used in this study. Effect of different mole ratios of calcium to sulfur (Ca/S ratio) on the combustion characteristics were also investigated. Results indicated that combustion performance indexes for bituminous coal impregnated by OCC were improved, however, an inverse trend was found for sewage sludge because sewage sludge has lower ignition temperature and higher volatile matter content compared to those of OCC. For rice husk, effect of added OCC on the combustion characteristics is not obvious. Different solid fuels show different combustion characteristics with increases of Ca/S ratio. The maximum combustion performance indexes appear at Ca/S ratios of 1:1, 2:1, and 3:1 for OCC blended with Shenhua coal, rice husk, and sewage sludge, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Influence of nitric acid concentration on the characteristics of active carbons obtained from a mineral coal

    Energy Technology Data Exchange (ETDEWEB)

    Khelifi, A.; Temdrara, L.; Addoun, A. [Laboratoire d' Etude Physicochimique des Materiaux et Application a l' Environnement, Faculte de Chimie, USTHB, BP. 32 El Alia, Bab Ezzouar 16111, Algiers (Algeria); Almazan-Almazan, M.C.; Perez-Mendoza, M.; Domingo-Garcia, M.; Lopez-Garzon, F.J [Departamento de Quimica Inorganica, Facultad de Ciencias, 18071 Granada (Spain); Lopez-Domingo, F.J. [Departamento de CCIA, ETS de Ingenieria Informatica y Telecomunicacion, Granada, 18071 (Spain)

    2010-10-15

    This paper deals with the effect of the concentration of nitric acid solutions on the properties of activated carbons obtained by the oxidation of a parent activated carbon. For this purpose a mineral coal from Algeria has been used as raw material to prepare the parent active carbon AC. This was further treated with nitric acid solutions. The analysis of the samples includes the chemical and textural characterization. The former was carried out by selective titrations and FTIR spectroscopy. The latter, by nitrogen and carbon dioxide adsorption at 77 and 273 K, respectively, and by adsorption of organic probes (benzene, dichloromethane, cyclohexane and 2,2-dimethyl butane) at 303 K. The nitrogen adsorption isotherms have been analysed by using the BET equation, {alpha}{sub s}-method and molecular simulation. The Dubinin-Radushkevich approach has been applied to the carbon dioxide and vapours adsorption data. The results show that the treatment with 2 N nitric acid solution is very appropriate because it introduces a large amount of oxygen containing groups with a small change of the textural characteristics of the parent AC. More concentrated nitric acid solutions change in large extent the textural properties although they also introduce large amount of chemical groups. (author)

  16. Hydrologic and water quality characteristics of a partially-flooded, abandoned underground coal mine

    International Nuclear Information System (INIS)

    Aljoe, W.W.

    1994-01-01

    The hydrologic and water quality characteristics of a partially flooded, abandoned underground coal mine near Latrobe, PA, were studied to support the development of techniques for in situ abatement of its acidic discharge. A quantitative understanding of the conditions affecting discharge flow was considered to be very important in this regard. Statistical analysis of hydrologic data collected at the site shows that the flow rate of the main discharge (a borehole that penetrates the mine workings just behind a set of portal seals) is a linear function of the height of the mine pool above the borehole outlet. Seepage through or around the portal seals is collected by a set of french drains whose discharge rate is largely independent of the mine pool elevation. This seepage was enhanced after a breakthrough that occurred during a period of unusually high pool levels. The mine pool recharge rate during winter is about 2.5 times greater than that of any other season; recharge rates during spring, summer, and fall are approximately equal. Mine pool and discharge water quality information, along with bromide tracer tests, suggest that the original main entries discharge primarily to the french drains, while the borehole carries the discharge from an unmonitored set of entries northwest of the mains. The water quality of the east french drain discharge may have been improved substantially after seepage through the alkaline materials used to construct the portal seals

  17. Influences of coal slag on electrical characteristics of a Faraday MHD generator

    International Nuclear Information System (INIS)

    Yoshida, M.; Umoto, J.

    1989-01-01

    In order to clarify the influence of coal slag on the electrical characteristics of a large scale Faraday MHD generator, numerical analysis by a new equivalent circuit method is performed. At first, an equivalent circuit for a space element in the Faraday channel and a slag layer element are derived. Next, the numerical results are compared with the experimental ones obtained from the ETL Mark VII. The results are: (1) when the thickness, conductivity, etc. of the slag are nonuniform the distribution of not only the load voltage, but also the voltage between adjacent electrodes, becomes nonuniform, and the latter may cause interelectrode breakdown; (2) when shorting over several cathodes occurs a typical distribution of the load voltage appears near the shorted region, in which, at first, the load voltage rises a little, then decreases gradually, and finally, recovers rapidly to the normal voltage along the gas flow. As a result of the short-circuit, the distribution of the voltage between adjacent electrodes is made significantly nonuniform, and this may lead to another inter-electrode breakdown. (author)

  18. Taxonomical and ecological characteristics of the desmids placoderms in reservoir: analyzing the spatial and temporal distribution

    Directory of Open Access Journals (Sweden)

    Sirlene Aparecida Felisberto

    2014-12-01

    Full Text Available AIM: This study aimed to evaluate the influence of river-dam axis and abiotic factors on the composition of Closteriaceae, Gonatozygaceae, Mesotaeniaceae and Peniaceae in a tropical reservoir METHODS: Water samples for physical, chemical and periphyton analysis were collected in April and August 2002 in different regions along the axis of the river-dam of Rosana Reservoir, River Basin Paranapanema. The substrates collected, always in the litoranea region, were petioles of Eichhornia azurea (Swartz Kunth. To examine the relationship of abiotic variables with reservoir zones and between the floristic composition of desmids, we used principal component analysis (PCA and canonical correspondence analysis (CCA RESULTS: The results of the PCA explained 81.3% of the total variability in the first two axes. In the first axis, the variables of conductivity, water temperature and the pH were related to the sampling regions of April with higher values, while for the month of August, nitrate, total phosphorus and dissolved oxygen showed higher values. We identified 20 taxa, distributed in the genera Closterium (14, Gonatozygon (4, Netrium (1 and Penium (1. Spatially, the higher taxa were recorded in the lacustrine region for both collection periods. The canonical correspondence analysis (CCA summarized 62.2% of total data variability of taxa in the first two axes, and in August, Closterium incurvum Brébisson, C. cornu Ehrenberg ex Ralfs and Gonatozygon monotaenium De Bary, were related to higher values of turbidity and nitrate to the lacustrine and intermediate regions CONCLUSION: Thus, the formation of groups was due to the regions along the longitudinal axis, then the seasonal period, which must be related to the low current velocity, the higher values of temperature and the water transparency, especially in late summer

  19. Discontinuities Characteristics of the Upper Jurassic Arab-D Reservoir Equivalent Tight Carbonates Outcrops, Central Saudi Arabia

    Science.gov (United States)

    Abdlmutalib, Ammar; Abdullatif, Osman

    2017-04-01

    Jurassic carbonates represent an important part of the Mesozoic petroleum system in the Arabian Peninsula in terms of source rocks, reservoirs, and seals. Jurassic Outcrop equivalents are well exposed in central Saudi Arabia and which allow examining and measuring different scales of geological heterogeneities that are difficult to collect from the subsurface due to limitations of data and techniques. Identifying carbonates Discontinuities characteristics at outcrops might help to understand and predict their properties and behavior in the subsurface. The main objective of this study is to identify the lithofacies and the discontinuities properties of the upper Jurassic carbonates of the Arab D member and the Jubaila Formation (Arab-D reservoir) based on their outcrop equivalent strata in central Saudi Arabia. The sedimentologic analysis revealed several lithofacies types that vary in their thickness, abundances, cyclicity and vertical and lateral stacking patterns. The carbonates lithofacies included mudstone, wackestone, packstone, and grainstone. These lithofacies indicate deposition within tidal flat, skeletal banks and shallow to deep lagoonal paleoenvironmental settings. Field investigations of the outcrops revealed two types of discontinuities within Arab D Member and Upper Jubaila. These are depositional discontinuities and tectonic fractures and which all vary in their orientation, intensity, spacing, aperture and displacements. It seems that both regional and local controls have affected the fracture development within these carbonate rocks. On the regional scale, the fractures seem to be structurally controlled by the Central Arabian Graben System, which affected central Saudi Arabia. While, locally, at the outcrop scale, stratigraphic, depositional and diagenetic controls appear to have influenced the fracture development and intensity. The fracture sets and orientations identified on outcrops show similarity to those fracture sets revealed in the upper

  20. Quality and petrographic characteristics of the lacustrine Ermenek coal (early Miocene), Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, I.H.; Karayigit, A.I. [Hacettepe Univ., Beytepe-Ankara (Turkey). Dept. of Geological Engineering

    1999-05-01

    The early Miocene Yenimahalle Formation including alluvial-lacustrine sediments and a mineable coal steam with an average of 5 m in thickness rests unconformably upon the basement and is also unconformably overlain by marine limestones of the middle-late Miocene Mut Formation in the Ermenek coal basin. The coal basin in the present study has been subdivided into two areas, Canakci and Pamuklu-Tepebasi, which are separated by the basement and a fault, in order to determine coal properties in detail. The investigated subbituminous coals with an average of 0.40%Ro huminite reflectance often contain gastropod shells (Planorbidae) which commonly maintain the original aragonite and calcite composition. The coals have similar chemical properties and petrographic composition in the two areas, but their sulphur contents are clearly different. In the Canakci area the coals on an air-dried basis contain distinctly less total sulphur (avg. 1.3%) and organic sulphur contents (0.13--0.15%) than in the Pamuklu-Tepebasi area (avg. 4.5% and 4.25%, respectively). This difference is interpreted to be controlled by mire chemistry and sedimentation during peat formation.

  1. Quality and petrographic characteristics of the Lacustrine Ermenek Coal (Early Miocene), Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, I.H.; Karayigit, A.I.

    1999-04-15

    The early Miocene Yenimahalle Formation including alluvial-lacustrine sediments and a mineable coal seam with an average of 5 m in thickness rests unconformably upon the basement and is also unconformably overlain by marine limestones of the middle-late Miocene Mut Formation in the Ermenek coal basin. The coal basin in the present study has been subdivided into two areas, Canakci and Pamuklu-Tepebasi, which are separated by the basement and a fault, in order to determine coal properties in detail. The investigated subbituminous coals with an average of 0.40% Ro huminite reflectance often contain gastropod shells (Planorbidae) which commonly maintain the original aragonite and calcite composition. The coals have similar chemical properties and petrographic composition in the two areas, but their sulphur contents are clearly different. In the Canakci area the coals on an air-dried basis contain distinctly less total sulphur (avg. 1.3%) and organic sulphur contents (0.13 0.15%) than in the Pamuklu-Tepebasi area (avg. 4.5% and 4.25%, respectively). This difference is interpreted to be controlled by mire chemistry and sedimentation during peat formation. (author)

  2. Electric-surface characteristics and stability of type K coal suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Baichenko, A A; Baran, A A; Mitina, N S; Kocherga, I I

    1987-07-01

    Investigates with the help of potentiometric titration, electrophoresis and conductometry the structure of double electric layer and aggregation stability of type K coal suspension at the Berezovsk preparation plant (Kuzbassugol' association). Discusses tests carried out with coal which was preliminarily crushed, sieved, crushed again in colloid mills, elutriated and separated into sedimento-stable fractions. Data obtained indicate that coal suspensions represent typical ion-stabilized dispersions, coagulation of which by electrolytes can be depicted within the framework of lyophobic colloid stability theory. Addition of double-charged gegenions considerably reduces electrokinetic potential while addition of triple-charged gegenions results in surface recharging. 10 refs.

  3. Characteristics of waterflooding of oil pools with clay-containing reservoir rocks

    Energy Technology Data Exchange (ETDEWEB)

    Zheltov, Yu V; Stupochenko, V E; Khavkin, A Ya; Martos, V N

    1981-01-01

    When planning the development of oil fields with reservoir pressure maintenance by the injection of water or activated solutions (surfactants, alkali, etc.), it is necessary to take into account the consequences of phenomena related to clay swelling. For this purpose, it is necessary to measure on a core the parameters characterizing the change and hysteresis of the filtration and storage properties of the reservoir rocks. Swelling of the clay component of the rock along with reducing these properties in the sweep zone can promote an increase of the efficiency of displacing oil by water. Theoretical investigations showed that the maximum displacement efficiency in homogeneous clay-containing rocks does not depend on the time of starting stimulation by demineralized waters. The efficiency from changing the mineralization of the stimulating agent increases with increase of viscosity of the oil. Under certain physical and geologic conditions, a purposeful change of the filtration and storage properties by increasing or decreasing clay swelling can increase the efficiency of developing the field and can increase oil recovery.

  4. Vegetation succession and soil infiltration characteristics under different aged refuse dumps at the Heidaigou opencast coal mine

    Directory of Open Access Journals (Sweden)

    Huang Lei

    2015-07-01

    Full Text Available Vegetation succession and soil infiltration characteristics under five different restoration models of refuse dumps including different-aged revegetated sites (1995, 1998, 2003 and 2005 in the northern, eastern and western open-pit coal mine dump and a reference site with native vegetation, which had never been damaged by coal mining activities on the Heidaigou Open Cut Coal Mine were studied. Changes in the plant species, soil properties and infiltration rates were evaluated at the different refuse dumps. The results indicated that the number of herbaceous species, plant cover, biomass, fine particles, and total N, P and SOM increased significantly with increasing site age. However, the number of shrub species decreased since revegetation, its cover increased from 17% to 41% initially and subsequently decreased to the present level of 4%. The natural vegetation community and the northern refuse dump had the highest cumulative infiltration rates of 3.96 and 2.89 cm s−1 in contrast to the eastern and western refuse dumps and the abandoned land, where the highest cumulative infiltration rates were 1.26, 1.04 and 0.88 cm s−1, respectively. A multiple linear regression analysis indicated that the infiltration rate was primarily determined by the silt percentage, SOM, plant coverage and the variation in soil bulk density. Our results provide new ideas regarding future soil erosion controls and sustainable development at open-pit coal mine refuse dumps.

  5. Implications of changing water cycle for the performance and yield characteristics of the multi-purpose Beas Reservoir in India

    Science.gov (United States)

    Adeloye, A. J.; Ojha, C. S.; Soundharajan, B.; Remesan, R.

    2013-12-01

    There is considerable change in both the spatial and temporal patterns of monsoon rainfall in India, with implications for water resources availability and security. 'Mitigating the Impacts of Climate Change on India Agriculture' (MICCI) is one of five on-going scientific efforts being sponsored as part of the UK-NERC/India-MOES Changing Water Cycle (South Asia) initiative to further the understanding of the problem and proffer solutions that are robust and effective. This paper focuses on assessing the implications of projected climate change on the yield and performance characteristics of the Pong Reservoir on the Beas River, Himachal Pradesh, India. The Pong serves both hydropower and irrigation needs and is therefore strategic for the socio-economic well-being of the region as well as sustaining the livelihoods of millions of farmers that rely on it for irrigation. Simulated baseline and climate-change perturbed hydro-climate scenarios developed as part of a companion Work Package of MICCI formed the basis of the analysis. For both of these scenarios, reservoir analyses were carried out using the Sequent Peak Algorithm (SPA) and Pong's existing level of releases to derive rule curves for the reservoir. These rule curves then formed the basis of further reservoir behaviour simulations in WEAP and the resulting performance of the reservoir was summarised in terms of reliability, resilience, vulnerability and sustainability. The whole exercise was implemented within a Monte Carlo framework for the benefit of characterising the variability in the assessments. The results show that the rule curves developed using future hydro-climate are significantly changed from the baseline in that higher storages will be required to be maintained in the Pong in the future to achieve reliable performance. As far as the overall performance of the reservoir is concerned, future reliability (both time-based and volume-based) is not significantly different from the baseline, provided

  6. Insights into Andean slope hydrology: reservoir characteristics of the thermal Pica spring system, Pampa del Tamarugal, northern Chile

    Science.gov (United States)

    Scheihing, Konstantin W.; Moya, Claudio E.; Tröger, Uwe

    2017-09-01

    The thermal Pica springs, at ˜1,400 m above sea level (asl) in the Pampa del Tamarugal (Chile), represent a low-saline spring system at the eastern margin of the hyper-arid Atacama Desert, where groundwater resources are scarce. This study investigates the hydrogeological and geothermal characteristics of their feed reservoir, fostered by the interpretation of a 20-km east-west-heading reflection-seismic line in the transition zone from the Andean Precordillera to the Pampa del Tamarugal. Additional hydrochemical, isotope and hydrologic time-series data support the integrated analysis. One of the main factors that enabled the development of the spring-related vertical fracture system at Pica, is a disruption zone in the Mesozoic Basement caused by intrusive formations. This destabilized the younger Oligocene units under the given tectonic stress conditions; thus, the respective groundwater reservoir is made up of fractured Oligocene units of low to moderate permeability. Groundwater recharge takes place in the Precordillera at ˜3,800 m asl. From there groundwater flow covers a height difference of ˜3,000 m with a maximum circulation depth of ˜800-950 m, where the waters obtain their geothermal imprint. The maximal expected reservoir temperature, as confirmed by geothermometers, is ˜55 °C. Corrected mean residence times of spring water and groundwater plot at 1,200-4,300 years BP and yield average interstitial velocities of 6.5-22 m/year. At the same time, the hydraulic head signal, as induced by recharge events in the Precordillera, is transmitted within 20-24 months over a distance of ˜32 km towards the Andean foothills at Pica and Puquio Nunez.

  7. Carbon emission as a function of energy generation in hydroelectric reservoirs in Brazilian dry tropical biome

    International Nuclear Information System (INIS)

    Ometto, Jean P.; Cimbleris, André C.P.; Santos, Marco A. dos; Rosa, Luiz P.; Abe, Donato; Tundisi, José G.; Stech, José L.; Barros, Nathan; Roland, Fábio

    2013-01-01

    Most energy generation globally is fueled by coal and oil, raising concerns about greenhouse gas emissions. Hydroelectric reservoirs are anthropogenic aquatic systems that occur across a wide geographical extent, and, in addition to their importance for energy production, they have the potential to release two important greenhouse gases (GHGs), carbon dioxide and methane. We report results from an extensive study of eight hydroelectric reservoirs located in central and southeastern tropical Brazil. In the Brazilian dry tropical biome reservoirs, emissions (in tons of CO 2 Eq. per MW h) varied from 0.01 to 0.55, and decreased with reservoir age. Total emissions were higher in the reservoir lake when compared to the river downstream the dam; however, emissions per unit area, in the first kilometer of the river after the dam, were higher than that in the reservoir. The results showed, despite higher carbon emissions per energy production in the youngest reservoirs, lower emission from hydroelectric reservoirs from the studied region in relation to thermo electrical supply, fueled by coal or fossil fuel. The ratio emission of GHG per MWh produced is an important parameter in evaluating the service provided by hydroelectric reservoir and for energy planning policies. - Highlights: ► Hydroelectric reservoirs construction is growing worldwide. ► The effect of hydropower reservoir in the carbon cycle is dependent on environment characteristics. ► Carbon emissions per energy production are higher in the youngest tropical savannah reservoirs. ► Methane emissions decrease with reservoir age in tropical savannah reservoirs. ► In general, the effect of hydropower in the carbon cycle is lower than other energy sources

  8. Ultravitrinite coals from Chukotka

    Energy Technology Data Exchange (ETDEWEB)

    Lapo, A.V.; Letushova, I.A.

    1979-03-01

    Chemical and petrographic analysis was conducted on coals from the Anadyrya and Bukhti Ugol'noi deposits. Characteristics of the most prevalent type of vitrinite coals in both regions are presented here. Anadyrya coals belong to a transitional phase between brown coal and long flame. Ultravitrinite coals predominate. Gas coals from Bukti Ugol'noi have a higher carbon content than Anadyrya coals. They also have a higher hydrogen content and yield of initial resin. In several cases there was also a higher yield of volatile substances. Chukotka coals are characterized by a 10 percent higher initial resin yield than equally coalified Donetsk coals, other indicators were equal to those of Donetsk coals. Because of this, Chukotka coals are suitable for fuel in power plants and as raw materials in the chemical industry. (15 refs.) (In Russian)

  9. Fractal Characteristics of Pores in Taiyuan Formation Shale from Hedong Coal Field, China

    Science.gov (United States)

    Li, Kunjie; Zeng, Fangui; Cai, Jianchao; Sheng, Guanglong; Xia, Peng; Zhang, Kun

    For the purpose of investigating the fractal characteristics of pores in Taiyuan formation shale, a series of qualitative and quantitative experiments were conducted on 17 shale samples from well HD-1 in Hedong coal field of North China. The results of geochemical experiments show that Total organic carbon (TOC) varies from 0.67% to 5.32% and the organic matters are in the high mature or over mature stage. The shale samples consist mainly of clay minerals and quartz with minor pyrite and carbonates. The FE-SEM images indicate that three types of pores, organic-related pores, inorganic-related pores and micro-fractures related pores, are developed well, and a certain number of intragranular pores are found inside quartz and carbonates formed by acid liquid corrosion. The pore size distributions (PSDs) broadly range from several to hundreds nanometers, but most pores are smaller than 10nm. As the result of different adsorption features at relative pressure (0-0.5) and (0.5-1) on the N2 adsorption isotherm, two fractal dimensions D1 and D2 were obtained with the Frenkel-Halsey-Hill (FHH) model. D1 and D2 vary from 2.4227 to 2.6219 and from 2.6049 to 2.7877, respectively. Both TOC and brittle minerals have positive effect on D1 and D2, whereas clay minerals, have a negative influence on them. The fractal dimensions are also influenced by the pore structure parameters, such as the specific surface area, BJH pore volume, etc. Shale samples with higher D1 could provide more adsorption sites leading to a greater methane adsorption capacity, whereas shale samples with higher D2 have little influence on methane adsorption capacity.

  10. Microseismic Precursory Characteristics of Rock Burst Hazard in Mining Areas Near a Large Residual Coal Pillar: A Case Study from Xuzhuang Coal Mine, Xuzhou, China

    Science.gov (United States)

    Cao, An-ye; Dou, Lin-ming; Wang, Chang-bin; Yao, Xiao-xiao; Dong, Jing-yuan; Gu, Yu

    2016-11-01

    Identification of precursory characteristics is a key issue for rock burst prevention. The aim of this research is to provide a reference for assessing rock burst risk and determining potential rock burst risk areas in coal mining. In this work, the microseismic multidimensional information for the identification of rock bursts and spatial-temporal pre-warning was investigated in a specific coalface which suffered high rock burst risk in a mining area near a large residual coal pillar. Firstly, microseismicity evolution prior to a disastrous rock burst was qualitatively analysed, and the abnormal clustering of seismic sources, abnormal variations in daily total energy release, and event counts can be regarded as precursors to rock burst. Secondly, passive tomographic imaging has been used to locate high seismic activity zones and assess rock burst hazard when the coalface passes through residual pillar areas. The results show that high-velocity or velocity anomaly regions correlated well with strong seismic activities in future mining periods and that passive tomography has the potential to describe, both quantitatively and periodically, hazardous regions and assess rock burst risk. Finally, the bursting strain energy index was further used for short-term spatial-temporal pre-warning of rock bursts. The temporal sequence curve and spatial contour nephograms indicate that the status of the danger and the specific hazardous zones, and levels of rock burst risk can be quantitatively and rapidly analysed in short time and in space. The multidimensional precursory characteristic identification of rock bursts, including qualitative analysis, intermediate and short-time quantitative predictions, can guide the choice of measures implemented to control rock bursts in the field, and provides a new approach to monitor and forecast rock bursts in space and time.

  11. Chemical Characteristics of Precipitation in a Typical Urban Site of the Hinterland in Three Gorges Reservoir, China

    Directory of Open Access Journals (Sweden)

    Liuyi Zhang

    2018-01-01

    Full Text Available Major water-soluble ions were analyzed for two-year precipitation samples in Wanzhou, a typical urban site of the hinterland of Chinese Three Gorges Reservoir. The pH values of the precipitation were in the range of 4.0 to 8.3, and the volume-weighted mean (VWM value was 5.0. The concentration order of anions and cations was as follows: SO42->NO3->Cl->F- and NH4+>Ca2+>Na+>K+>Mg2+, respectively. Good correlations were found between SO42- and NH4+, SO42- and Ca2+, NO3- and NH4+, and NO3- and Ca2+, implying their co-occurrence in the precipitation, most likely as (NH42SO4, (NH4HSO4, NH4NO3, CaSO4, and Ca(NO32. The sum of all measured ions was 416.4 μeq L−1, indicating serious air pollution in Wanzhou. NH4+ and Ca2+ were the most important ions neutralizing the acidic compounds in the precipitation; their major sources included agricultural activity and crustal dust. Local anthropogenic activities, for example, coal burning and traffic related sources, contributed most of SO42- and NO3-. The equivalent concentration ratio of SO42-/NO3- was 4.5, indicating that excessive emission of sulfur was the main reason leading to the precipitation acidity in Wanzhou. However, this ratio was lower than the ratio (5.9 in 2000s in Wanzhou, indicating that the contribution of nitric acid to the acidity of precipitation was strengthening.

  12. Studies on catalytic hydrotreating of recycled solvents from coal liquefaction process. Part 1. Characteristics changes of recycled solvents during hydrotreating

    Energy Technology Data Exchange (ETDEWEB)

    Morimura, Y.; Nakata, S.; Yokota, Y.; Shirota, Y.; Nakamura, M. [Chiyoda Corp., Tokyo (Japan); Mitarai, Y. [Sumitomo Metal Mining Co. Ltd., Tokyo (Japan); Inoue, Y. [Nippon Ketjen Co. Ltd., Tokyo (Japan)

    1995-07-01

    A bituminous coal liquefaction process, called the NEDOL process, is under development by the New Energy and Industrial Technology Development Organization (NEDO). Important features of this process include the capacity to produce hydrogen-donatable solvents, obtained by hydrogenation of middle distillates of coal derived oils, and to recycle these solvents to a liquefaction stage as hydrogen donor solvents. These recycled solvents, obtained by liquefaction of Wandoan coal, and their catalytic hydrotreated oils, have been extensively characterized, using a variety of analytical methods. The following items have been examined and are discussed in this study: (1) Influence of chemical hydrogen consumption on the reactivities of hydrodesulfurization (HDS), hydrodenitrogenation (HDN), hydrodeoxygenation (HDO) and hydrogenation of aromatic-rings, during hydrotreating; (2) Changes in composition of hydrocarbon types, nitrogen- and oxygen-containing compounds, as a function of chemical hydrogen consumption; (3) Changes of average molecular weights; (4) Characteristics changes of oxygen- and nitrogen-containing compounds, and reactivities of HDO and HDN; (5) Characteristics changes of donatable hydrogen as a function of a degree of hydrogenation ({delta}fa). 14 refs., 14 figs., 3 tabs.

  13. Experimental study on the response characteristics of coal permeability to pore pressure under loading and unloading conditions

    Science.gov (United States)

    Ye, Zhiwei; Zhang, Lei; Hao, Dingyi; Zhang, Cun; Wang, Chen

    2017-10-01

    In order to study the response characteristics of coal permeability to pore pressure, seepage experiments under different simulated in situ stresses on loading and unloading paths are carried out using the self-developed Gas Flow and Displacement Testing Apparatus (GFDTA) system. Based on the analysis of the experimental data, the relationship between average pore pressure and permeability is found to basically obey the function distribution of a two degree polynomial. In this paper, two aspects of the relationship between permeability and pore pressure are explained: the Klinbenberg effect and expansion, and the penetration of the initial fracture. Under low pore pressure, the decrease in the Klinbenberg effect is the main reason for the decrease in permeability with increased pore pressure. Under relatively high pore pressure, the increase in pore pressure leads to the initial fracture expansion and penetration of the coal sample, which causes an increase in permeability. In order to evaluate the sensitivity of the permeability response to pore pressure changes, the permeability dispersion and pore pressure sensitivity coefficients are defined. After the sensitivity analysis, it was concluded that the loading history changed the fracture structure of the original coal sample and reduced its permeability sensitivity to pore pressure. Under low pore pressure, the Klinbenberg effect is the reason for the decrease in pore pressure sensitivity. Lastly, the permeability-pore pressure relationship is divided into three stages to describe the different response characteristics individually.

  14. Geochemical characteristics of crude oil from a tight oil reservoir in the Lucaogou Formation, Jimusar Sag, Junggar Basin

    Science.gov (United States)

    Cao, Z.

    2015-12-01

    Jimusar Sag, which lies in the Junggar Basin,is one of the most typical tight oil study areas in China. However, the properties and origin of the crude oil and the geochemical characteristics of the tight oil from the Lucaogou Formation have not yet been studied. In the present study, 23 crude oilsfrom the Lucaogou Formation were collected for analysis, such as physical properties, bulk composition, saturated hydrocarbon gas chromatography-mass spectrometry (GC-MS), and the calculation of various biomarker parameters. In addition,source rock evaluation and porosity permeability analysis were applied to the mudstones and siltstones. Biomarkers of suitable source rocks (TOC>1, S1+S2>6mg/g, 0.7%reservoir is a typical in situ reservoir. The mudstones over or beneath the sweet spot bodies consisted of natural caprocks and prevented the vertical movement of oil by capillary forces. Despite being thicker, the thick-bedded mudstone between the upper and lower sweet spots had no obvious contribution to

  15. LIQUID COAL CHARACTERISTIC ANALYSIS WITH FOURIER TRANSFORM INFRA RED (FTIR AND DIFFERENTIAL SCANNING CALORIMETER (DSC

    Directory of Open Access Journals (Sweden)

    ATUS BUKU

    2017-02-01

    Full Text Available The aim of this study is to identify the value of compounds contained in liquid coal by using Fourier Transform Infra-Red (FTIR and Differential Scanning Calorimeter (DSC. FTIR was used to analyse the components contained in liquid coal, while the DSC is done to observe the heat reaction to the environment. Based on the Fourier Transform Infra-Red (FTIR test results it is shown that the compound contained in the liquid Coal consisting of alkanes, alkenes and alkyne. These compounds are similar compounds. The alkanes, alkenes and alkynes compounds undergo complete combustion reaction with oxygen and would produce CO2 and water vapour [H2O (g]. If incomplete combustion occurs, the reaction proceeds in the form of Carbon Monoxide CO gas or solid carbon andH2O. Combustion reaction that occurs in all these three compounds also produces a number of considerable energy. And if it has higher value of Carbon then the boiling point would be higher. From the Differential Scanning Calorimetric (DSC test results obtained some of the factors that affect the reaction speed, which are the temperature, the reaction mixture composition, and pressure. Temperature has a profound influence in coal liquefaction, because if liquid coal heated with high pressure, the carbon chain would break down into smaller chains consisting of aromatic chain, hydro-aromatic, or aliphatic. This then triggers a reaction between oil formation and polymerization reactions to form solids (char.

  16. Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

    Science.gov (United States)

    Zhao, Tong; Liu, Changyou

    2017-12-01

    Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

  17. unconventional natural gas reservoirs

    International Nuclear Information System (INIS)

    Correa G, Tomas F; Osorio, Nelson; Restrepo R, Dora P

    2009-01-01

    This work is an exploration about different unconventional gas reservoirs worldwide: coal bed methane, tight gas, shale gas and gas hydrate? describing aspects such as definition, reserves, production methods, environmental issues and economics. The overview also mentioned preliminary studies about these sources in Colombia.

  18. Characteristic Study of Some Different Kinds of Coal Particles Combustion with Online TG-MS-FTIR

    Science.gov (United States)

    Pan, Guanfu

    2018-01-01

    Four kinds of pulverized coal samples from China and Indonesia were studied by thermogravimetry coupled with mass spectrometry and fourier transform infrared spectroscopy (TG-MS-FTIR). The thermal behaviors and gaseous emissions of these coals were analyzed in this work. The results indicate that the relative lower values of H/C ratios, which normally represent the degree of aromatization and ring condensation in coal samples, could lead to the relative more intense thermal reaction. The time-evolved profiles of some typical gas products (i.e., CO, SO2, CH4, NO, NO2, NH3 and etc.) were provided by TG-MS-FTIR, and their variations are different. For all the samples, the releases of SO2 and COS can be found at lower temperature than those of NO and CO. As the temperature increases, the possible conversion of NO2 and NH3 to NO is deduced in this work.

  19. Importance of the textural characteristics of inert additives in the reduction of coal thermoplastic properties

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Fernandez; C. Barriocanal; M.A. Diez; R. Alvarez [Instituto Nacional del Carbon, Oviedo (Spain)

    2010-11-15

    Seven carbonaceous materials of different origin were chosen in order to study the influence of their porous structure on the modification of the thermoplastic properties of a bituminous coal. The materials included were: two non-coking coals, a petroleum coke, coke fines, two residues from tyre recycling and a bituminous residue. The materials were heat-treated to 900{sup o}C to prevent any chemical interaction between the volatiles evolved during co-carbonization. The thermoplastic properties of blends that contained 10 wt.% of additive were measured by means of the Gieseler test. Microporosity was measured by CO{sub 2} adsorption at 273 K, whereas meso and macroporosity were determined by means of mercury porosimetry. The results of the porous structure assessment are discussed in relation to the modification of coal plasticity. 32 refs., 5 figs., 5 tabs.

  20. Volatile release and particle formation characteristics of injected pulverized coal in blast furnaces

    International Nuclear Information System (INIS)

    Chen, Wei-Hsin; Du, Shan-Wen; Yang, Tsung-Han

    2007-01-01

    Volatiles release and particle formation for two kinds of pulverized coals (a high volatile bituminous coal and a low volatile bituminous coal) in a drop tube furnace are investigated to account for the reactions of pulverized coal injected in blast furnaces. Two different sizes of feed particles are considered; one is 100-200 mesh and the other is 200-325 mesh. By evaluating the R-factor, the devolatilization extent of the larger feed particles is found to be relatively poor. However, the swelling behavior of individual or two agglomerated particles is pronounced, which is conducive to gasification of the chars in blast furnaces. In contrast, for the smaller feed particles, volatiles liberated from the coal particles can be improved in a significant way as a result of the amplified R-factor. This enhancement can facilitate the performance of gas phase combustion. Nevertheless, the residual char particles are characterized by agglomeration, implying that the reaction time of the char particles will be lengthened, thereby increasing the possibility of furnace instability. Double peak distributions in char particle size are observed in some cases. This possibly results from the interaction of the plastic state and the blowing effect at the particle surface. Considering the generation of tiny aerosols composed of soot particles and tar droplets, the results indicate that their production is highly sensitive to the volatile matter and elemental oxygen contained in the coal. Comparing the reactivity of the soot to that of the unburned char, the former is always lower than the latter. Consequently, the lower is the soot formation, the better is the blast furnace stability

  1. The Contribution of Individual, Social and Work Characteristics to Employee Mental Health in a Coal Mining Industry Population.

    Directory of Open Access Journals (Sweden)

    Robyn Considine

    Full Text Available Evidence regarding the extent of mental health problems and the associated characteristics within an employee population is necessary to inform appropriate and tailored workplace mental health programs. Mental health within male dominated industries (such as mining has received recent public attention, chiefly through observations regarding suicide in such populations in Australia and internationally. Currently there is limited empirical evidence regarding the mental health needs in the mining industry as an exemplar of a male dominated workforce, and the relative contribution to such problems of individual, socio-economic and workplace factors. This study aimed to investigate the mental health and associated characteristics among employees in the Australian coal mining industry with a specific focus on identifying modifiable work characteristics.A cross-sectional study was conducted among employees (n = 1457 across eight coal mines stratified by key mine characteristics (state, mine type and employee commute arrangements. Participants completed measures of psychological distress (K10+ and key variables across four categories (socio-demographic characteristics, health history, current health behaviours, work attitudes and characteristics.Psychological distress levels within this sample were significantly higher in comparison with a community sample of employed Australians. The following factors contributed significantly to levels of psychological distress using hierarchical linear regression analysis: lower social networks; a past history of depression, anxiety or drug/alcohol problems; high recent alcohol use; work role (managers and a set of work characteristics (level of satisfaction with work, financial factors and job insecurity; perception of lower workplace support for people with mental health problems.This is the first study to examine the characteristics associated with mental health problems in the Australian coal mining industry. The

  2. The Contribution of Individual, Social and Work Characteristics to Employee Mental Health in a Coal Mining Industry Population.

    Science.gov (United States)

    Considine, Robyn; Tynan, Ross; James, Carole; Wiggers, John; Lewin, Terry; Inder, Kerry; Perkins, David; Handley, Tonelle; Kelly, Brian

    2017-01-01

    Evidence regarding the extent of mental health problems and the associated characteristics within an employee population is necessary to inform appropriate and tailored workplace mental health programs. Mental health within male dominated industries (such as mining) has received recent public attention, chiefly through observations regarding suicide in such populations in Australia and internationally. Currently there is limited empirical evidence regarding the mental health needs in the mining industry as an exemplar of a male dominated workforce, and the relative contribution to such problems of individual, socio-economic and workplace factors. This study aimed to investigate the mental health and associated characteristics among employees in the Australian coal mining industry with a specific focus on identifying modifiable work characteristics. A cross-sectional study was conducted among employees (n = 1457) across eight coal mines stratified by key mine characteristics (state, mine type and employee commute arrangements). Participants completed measures of psychological distress (K10+) and key variables across four categories (socio-demographic characteristics, health history, current health behaviours, work attitudes and characteristics). Psychological distress levels within this sample were significantly higher in comparison with a community sample of employed Australians. The following factors contributed significantly to levels of psychological distress using hierarchical linear regression analysis: lower social networks; a past history of depression, anxiety or drug/alcohol problems; high recent alcohol use; work role (managers) and a set of work characteristics (level of satisfaction with work, financial factors and job insecurity; perception of lower workplace support for people with mental health problems. This is the first study to examine the characteristics associated with mental health problems in the Australian coal mining industry. The findings

  3. Change in surface characteristics of coal in upgrading of low-rank coals; Teihin`itan kaishitsu process ni okeru sekitan hyomen seijo no henka

    Energy Technology Data Exchange (ETDEWEB)

    Oki, A.; Xie, X.; Nakajima, T.; Maeda, S. [Kagoshima University, Kagoshima (Japan). Faculty of Engineering

    1996-10-28

    With an objective to learn mechanisms in low-rank coal reformation processes, change of properties on coal surface was discussed. Difficulty in handling low-rank coal is attributed to large intrinsic water content. Since it contains highly volatile components, it has a danger of spontaneous ignition. The hot water drying (HWD) method was used for reformation. Coal which has been dry-pulverized to a grain size of 1 mm or smaller was mixed with water to make slurry, heated in an autoclave, cooled, filtered, and dried in vacuum. The HWD applied to Loy Yang and Yallourn coals resulted in rapid rise in pressure starting from about 250{degree}C. Water content (ANA value) absorbed into the coal has decreased largely, with the surface made hydrophobic effectively due to high temperature and pressure. Hydroxyl group and carbonyl group contents in the coal have decreased largely with rising reformation treatment temperature (according to FT-IR measurement). Specific surface area of the original coal of the Loy Yang coal was 138 m{sup 2}/g, while it has decreased largely to 73 m{sup 2}/g when the reformation temperature was raised to 350{degree}C. This is because of volatile components dissolving from the coal as tar and blocking the surface pores. 2 refs., 4 figs.

  4. Methods for Evaluating Capping Capacity of Roof and Floor of Coal Reservoir with Logging Data%用测井资料评价煤储层顶底板封盖性的方法

    Institute of Scientific and Technical Information of China (English)

    高敏; 蔡文渊; 罗安银; 刘百舟; 张莉莉; 袁文娟; 雷卓

    2012-01-01

    This paper describes four methods for evaluating the capping property of roof and floor of coal seam. They are : ( 1 ) the method for computation of lithology ratio and thickness of roof and floor of coal reservoir by using the conventional logging data; (2) Nuclear magnetic logging method for analysis of po rosity, water carrying property and pore structure of roof and floor of coal reservoir; (3) Method for eval uating fracture development and connectivity of the roof and floor using micro resistivity scanning and imaging log; (4) Analysis of the gassiness, natural fracture, permeability and formation anisotropy of the coal reservoir and its roof and floor using rock mechanics parameters obtained from array sonic logging da ta. This paper discusses the different logging response of the seam roof and floor in the above evaluating methods.%本文介绍了用测井资料评价煤储层顶底板封盖性的四种方法。包括:用常规测井资料计算煤储层顶底板围岩的岩性比、厚度的方法;用核磁测井进行煤储层顸底板孔隙性、含水性和孔隙结构分析的方法;用微电阻率扫描成像测井进行煤储层顶底板裂缝发育程度与连通性评价的方法;用阵列声波测井资料提供的岩石力学参数进行煤储层及其顶底板地层含气性、天然裂缝及渗透性、地层各向异性等分析的方法。论述了煤储层顶底板封盖性的好与差在以上四种评价方法上的测井响应特征各不相同。

  5. Hydraulic characteristics and sediment generation on slope erosion in the Three Gorges Reservoir Area, China

    Directory of Open Access Journals (Sweden)

    Qian Feng

    2016-09-01

    Full Text Available Hydrological processes play important roles in soil erosion processes of the hillslopes. This study was conducted to investigate the hydrological processes and the associated erosional responses on the purple soil slope. Based on a comprehensive survey of the Wangjiaqiao watershed in the Three Gorges Reservoir, four typical slope gradients (5°, 10°, 15°and 20° were applied to five rainfall intensities (0.6, 1.1, 1.61, 2.12 and 2.54 mm·min-1. The results showed that both surface and subsurface runoff varied greatly depending on the rainfall intensity and slope gradient. Surface runoff volume was 48.1 to 280.1 times of that for subsurface runoff. The critical slope gradient was about 10°. The sediment yield rate increased with increases in both rainfall intensity and slope gradient, while the effect of rainfall intensity on the sediment yield rate was greater than slope gradient. There was a good linear relationship between sediment yield rate and Reynolds numbers, flow velocity and stream power, while Froude numbers, Darcy-Weisbach and Manning friction coefficients were not good hydraulic indicators of the sediment yield rate of purple soil erosion. Among the three good indicators (Re, v and w, stream power was the best predictor of sediment yield rate (R2 = 0.884. Finally, based on the power regression relationship between sediment yield rate, runoff rate, slope gradient and rainfall intensity, an erosion model was proposed to predict the purple soil erosion (R2 = 0.897. The results can help us to understand the relationship between flow hydraulics and sediment generation of slope erosion and offer useful data for the building of erosion model in purple soil.

  6. Analysis on the spatiotemporal characteristics of water quality and trophic states in Tiegang Reservoir: A public drinking water supply reservoir in South China

    Science.gov (United States)

    Song, Yun-long; Zhu, Jia; Li, Wang; Tao, Yi; Zhang, Jin-song

    2017-08-01

    Shenzhen is the most densely populated city in China and with a severe shortage of water. The per capita water resource is less than 200 m3, which is approximately 1/12 of the national average level. In 2016, nearly 90% of Shenzhen’s drinking water needed to be imported from the Pearl River. After arrived at Shenzhen, overseas water was firstly stockpiled in local reservoirs and then was supplied to nearby water works. Tiegang Reservoir is the largest drinking water supply reservoir and its water quality has played an important role to the city’s drinking water security. A fifteen-month’s field observation was conducted from April 2013 to June 2014 in Tiegang Reservoir, in order to analyze the temporal and spatial distribution of water quality factors and seasonal variation of trophic states. One-way ANOVA showed that significant difference was found in water quality factors on month (p latter rainy period > high temperature and rain free period > temperature jump period > winter drought period, while SD showed the contrary. Two-way ANOVA showed that months rather than locations were the key influencing factors of water quality factors succession. Tiegang reservoir was seriously polluted by TN, as a result WQI were at IV∼V level. If TN was not taken into account, WQI were atI∼III level. TLI (Σ) were about 35∼60, suggesting Tiegang reservoir was in mesotrophic and light-eutrophic trophic states. The WQI and TLI (Σ) in sampling sites 9 and 10 were poorer than that of other sites. The 14 water quality factors were divided into 5 groups by factor analysis (FA). The total interpretation rate was 73.54%. F1 represents the climatic change represented by water temperature. F2 and F4 represent the concentration of nutrients. F3 and F5 represent the sensory indexes of water body, such as turbidity, transparency. The FA results indicated that water quality potential risk factors was total nitrogen (TN), and potential risk factors also include chlorophyll-a and

  7. Experimental investigation of ash deposits characteristics of co-combustion of coal and rice hull using a digital image technique

    International Nuclear Information System (INIS)

    Qiu, Kunzan; Zhang, Hailong; Zhou, Hao; Zhou, Bin; Li, Letian; Cen, Kefa

    2014-01-01

    This paper investigated the ash deposit characteristics during the co-firing Da Tong (DA) coal with different proportions of rice hull (0%, 5%, 10%, and 20%, based on weight) in a pilot-scale furnace. The growth of ash deposit with a four-stage mode was presented. The stable thickness values of DA coal, 5% rice hull, 10% rice hull, and 20% rice hull were 0.5, 1.4, 2.9, 5.7 cm, with stable heat flux values of 230, 200, 175, and 125 kW/m 2 , respectively. According to the results of scanning electron microscopy with energy dispersive X-ray analysis (SEM-EDX), the amount of Si in the deposits increased with the increasing proportion of rice hull rich in SiO 2 . The X-ray diffraction (XRD) analysis results indicated that most elements except Si were in the amorphous state because of the formation of eutectics. The stable thicknesses of deposits increased exponentially with the proportion of rice hull. The deposit was loose, easy removable but it reduced the heat transfer significantly. Consequently, sootblowing timely was necessary when co-firing DA coal with rice hull. - Highlights: • Digital image technique was used to monitor deposits growth process. • A type of four stages mode of ash deposit growth was presented. • The heat flux of ash deposits fit a three-stage mode. • The addition of rice hull increased the porosity of deposits

  8. Change of brown coal oxidation kinetic characteristics by promoting additives appending in the form of copper salts

    Science.gov (United States)

    Larionov, K. B.; Mishakov, I. V.; Gromov, A. A.; Zenkov, A. V.

    2017-11-01

    Process of brown coal oxidation with 5%wt content of copper-salt additives of various nature (Cu (NO3)2, CuSO4 and Cu(CH3COO)2) was studied. The experiment has been performed by thermogravimetric analysis at a heating rate of 2.5°C/min to a maximum temperature of 600°C in the air. Analytical evaluation of oxidation process kinetic characteristics has been conducted based on the results of TGA. It has been established that addition of initiating agents leads to significant reduction in the initial ignition temperature of coal (ΔTi = 15÷40°C), shortening of the sample warm-up time to the ignition point (Δte = 6÷12 min) and reduction of the sample burning time (Δtf = 40÷54 min). The following series of additives activity affecting ignition temperature of coals has been established: Cu(CH3COO)2 > Cu(NO3)2 > CuSO4. Additionally, the opposite can be said about the effect of additives on residence time of the sample in its combustion area (CuSO4 > Cu(NO3)2 > Cu(CH3COO)2). According to mass spectrometric analysis, presence of NOx, SO2, CO2 (intense peaks at 190÷290°C) was recorded in oxidation products of modified samples, which is explained by partial or complete decomposition of salts.

  9. Distribution characteristics of aromatic hydrocarbons pollution in dustfall samples from a coal-mining area, China

    Energy Technology Data Exchange (ETDEWEB)

    Yang Ce; Zhong Ning-ning; Chen Dang-yi; Li yan; Liu Shuang [China University of Petroleum, Beijing (China). Key Laboratory for Hydrocarbon Accumulation

    2007-07-01

    Dustfall samples from the Shilong coal-mining area, Pingdingshan, Henan, China, were tested containing polycyclic aromatic hydrocarbons (PAHs) by means of GC-MS technology, which damage the health of human. One hundred and sixty-nine PAHs have been identified in the samples, including 13 US EPA PAHs. The concentrations of PAHs are different in different dustfall samples from various site, which change from 0.017 to 0.188 mg/g, and the mean value is 0.079 mg/g. Of all the PAHs with 2-7 rings, PAHs with 3 rings are the most abundant. Considering organic geochemical parameters such as MP/P, MPI1, FL/PY and biomarkers, we conclude that lots of coalmines and coal industry plants, which locate in the small area, could have direct effect on the ambient atmosphere. Coal dust and coal combustion products influence the component of PAHs in the atmosphere. In addition, straw and wood combustion are small sources for PAHs. 30 refs., 7 figs., 1 tab.

  10. COMPARATIVE CHARACTERISTICS OF MORPHOMETRIC PARAMETERS OF MONKEY GOBY (NEOGOBIUS FLUVIATILIS PALLAS OF FRESH AND SALINE WATER RESERVOIRS IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Onoprienko V.

    2014-04-01

    physiological processes. The result of this effect is the difference in weight, size and body parts. To clarify, as our model species was taken Cottus Sandpiper (Neogobius fluviatilis Pallas. The reason for this was the fact that this species, along with other Ponto- Caspian solonovato - freshwater gobies, the International Union for Conservation of Nature classified as species biology are poorly understood and require further research. This fact that deepened interest of ichthyologists in this group of fish, in this regard appeared in the literature as material for the bulls and in Sandpiper. Based on the above, the purpose of this paper is a comparative morphometric parameters characteristic of individuals of this species of fresh and salt water bodies of Ukraine. All this affects the absolute morphometric parameters, which decrease in the direction from sea to the river. However, it should be noted that in rivers with rich feeding grounds sheer size of some individuals close to the size and species of sea Kakhovskoe reservoir. This situation is observed in the Sandpiper Grouse River. Here are some specimens reach a length (TL 118-148 mm and a weight of 15-36 g, Kakhovskoe Reservoir: 106-150 mm 11-38 g, in the Sea of Azov: 115-174 mm 17-58 g. For relative parameters Sandpiper with these reservoirs are more similar, however, for some of them, there are differences. Among the latter is most clearly distinguished the ratio SL / N. This indicator podovzhenist (prohonystist body. As pointed out by VP Mitrofanov (1977, this indicator shows the hydrodynamic qualities of fish: the larger the index, the more active lifestyle is individual. When compared with individuals with a little water and a large stream, in the latter case, individuals are more elongated. This is confirmed by our material: the ratio SL / L for the smallest species of sea of Azov (4.96, slightly more for Kakhovsky reservoir (5.52 and even more for rivers Grouse, Trubizh, Desna, Ros (respectively 5, 86, 6.22 , 6

  11. COMPARATIVE CHARACTERISTICS OF MORPHOMETRIC PARAMETERS OF MONKEY GOBY (NEOGOBIUS FLUVIATILIS PALLAS OF FRESH AND SALINE WATER RESERVOIRS IN UKRAINE

    Directory of Open Access Journals (Sweden)

    V. P. Onoprienko

    2014-04-01

    physiological processes. The result of this effect is the difference in weight, size and body parts. To clarify, as our model species was taken Cottus Sandpiper (Neogobius fluviatilis Pallas. The reason for this was the fact that this species, along with other Ponto- Caspian solonovato - freshwater gobies, the International Union for Conservation of Nature classified as species biology are poorly understood and require further research. This fact that deepened interest of ichthyologists in this group of fish, in this regard appeared in the literature as material for the bulls and in Sandpiper. Based on the above, the purpose of this paper is a comparative morphometric parameters characteristic of individuals of this species of fresh and salt water bodies of Ukraine. All this affects the absolute morphometric parameters, which decrease in the direction from sea to the river. However, it should be noted that in rivers with rich feeding grounds sheer size of some individuals close to the size and species of sea Kakhovskoe reservoir. This situation is observed in the Sandpiper Grouse River. Here are some specimens reach a length (TL 118-148 mm and a weight of 15-36 g, Kakhovskoe Reservoir: 106-150 mm 11-38 g, in the Sea of ​​Azov: 115-174 mm 17-58 g. For relative parameters Sandpiper with these reservoirs are more similar, however, for some of them, there are differences. Among the latter is most clearly distinguished the ratio SL / N. This indicator podovzhenist (prohonystist body. As pointed out by VP Mitrofanov (1977, this indicator shows the hydrodynamic qualities of fish: the larger the index, the more active lifestyle is individual. When compared with individuals with a little water and a large stream, in the latter case, individuals are more elongated. This is confirmed by our material: the ratio SL / L for the smallest species of sea of ​​Azov (4.96, slightly more for Kakhovsky reservoir (5.52 and even more for rivers Grouse, Trubizh, Desna, Ros (respectively 5, 86

  12. A novel method for estimating methane emissions from underground coal mines: The Yanma coal mine, China

    Science.gov (United States)

    Ji, Zhong-Min; Chen, Zhi-Jian; Pan, Jie-Nan; Niu, Qing-He

    2017-12-01

    As the world's largest coal producer and consumer, China accounts for a relatively high proportion of methane emissions from coal mines. Several estimation methods had been established for the coal mine methane (CMM) emission. However, with large regional differences, various reservoir formation types of coalbed methane (CBM) and due to the complicated geological conditions in China, these methods may be deficient or unsuitable for all the mining areas (e.g. Jiaozuo mining area). By combing the CMM emission characteristics and considering the actual situation of methane emissions from underground coal mine, we found that the methane pre-drainage is a crucial reason creating inaccurate evaluating results for most estimation methods. What makes it so essential is the extensive pre-drainage quantity and its irrelevance with annual coal production. Accordingly, the methane releases were divided into two categories: methane pre-drainage and methane release during mining. On this basis, a pioneering method for estimating CMM emissions was proposed. Taking the Yanma coal mine in the Jiaozuo mining area as a study case, the evaluation method of the pre-drainage methane quantity was established after the correlation analysis between the pre-drainage rate and time. Thereafter, the mining activity influence factor (MAIF) was first introduced to reflect the methane release from the coal and rock seams around where affected by mining activity, and the buried depth was adopted as the predictor of the estimation for future methane emissions. It was verified in the six coal mines of Jiaozuo coalfield (2011) that the new estimation method has the minimum errors of 12.11%, 9.23%, 5.77%, -5.20%, -8.75% and 4.92% respectively comparing with other methods. This paper gives a further insight and proposes a more accurate evaluation method for the CMM emissions, especially for the coal seams with low permeability and strong tectonic deformation in methane outburst coal mines.

  13. EDS Coal Liquefaction Process Development. Phase V. Laboratory evaluation of the characteristics of EDS Illinois bottoms

    Energy Technology Data Exchange (ETDEWEB)

    Lao, T C; Levasseur, A A

    1984-02-01

    This interim report documents work carried out by Combustion Engineering, Inc. under a contract to Exxon Research and Engineering Company to develop a conceptual Hybrid Boiler design fueled by the vacuum distillation residue (vacuum bottoms) derived from Illinois No. 6 coal in the EDS Coal Liquefaction Process. This report was prepared by Combustion Engineering, Inc., and is the first of two reports on the predevelopment phase of the Hybrid Boiler program. This report covers the results of a laboratory investigation to assess the fuel and ash properties of EDS vacuum bottoms. The results of the laboratory testing reported here were used in conjunction with Combustion Engineering's design experience to predict fuel performance and to develop appropriate boiler design parameters. These boiler design parameters were used to prepare the engineering design study reported in EDS Interim Report FE-2893-113, the second of the two reports on the predevelopment phase of the Hybrid Boiler Program. 46 figures, 29 tables.

  14. Design characteristics of the Belchatow brown coal mine in light of achievements of the Poltegor center

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, Z [Akademia Gorniczo-Hutnicza, Cracow (Poland)

    1988-01-01

    Discusses development of the Belchatow mine design by the Poltegor center in Wroclaw (coordinator of the project). Research units in Wroclaw (University and Technical University), Gliwice (Silesian Technical University), Cracow (Academy of Mining and Metallurgy) also participated in the project. The following stages of coal exploration and planning of surface mining at Belchatow are discussed: evaluation of mining and geologic conditions, assessment of coal reserves and calorific value, selecting optimum scheme for deposit opening, planning development of the Belchatow district, design of bucket wheel excavators, belt conveyor systems and stackers, development of heavy-duty mining equipment for the largest and deepest surface mine in Poland, design development of auxiliary installations, planning earthmoving operations. Selected specific problems associated with the Belchatow mine solved by Poltegor are discussed: seismic shocks, mine draining, landslide hazards.

  15. Multi-scale characteristics of coal structure by x-ray computed tomography (x-ray CT), scanning electron microscope (SEM) and mercury intrusion porosimetry (MIP)

    Science.gov (United States)

    Cai, Ting-ting; Feng, Zeng-chao; Zhou, Dong

    2018-02-01

    It is of great benefit to study the material and structural heterogeneity of coal for better understanding the coalbed methane (CBM) storage and enrichment. In this paper, multi-scale X-ray computed tomography (CT), scanning electron microscope (SEM) and mercury intrusion porosimetry (MIP) at multi scales were conducted to thoroughly study the material distribution, heterogeneity, pore development, porosity and permeability of coal. It is suitable and reasonable to divide the testing samples into three structural categories by average density and heterogeneity degree, and the meso structure in the three categories accords with the morphology on SEM images. The pore size distribution and pore development of each subsample cannot be correspondingly related to their respective structure category or morphology due to different observation scales, while the macro pore size development, accumulated macro pore volume and macro pores porosity accord with the meso structure category and morphology information by CT and SEM at the same scale very well. Given the effect of macro pores on permeability and the contribution of micro pores to CBM storage capacity, reservoirs with developed micro pores and macro pores may be the most suitable coal reservoir for CBM exploitation.

  16. Coal background paper. Coal demand

    International Nuclear Information System (INIS)

    1997-01-01

    Statistical data are presented on coal demands in IEA and OECD member countries and in other countries. Coal coaking and coaking coal consumption data are tabulated, and IEA secretariat's coal demand projections are summarized. Coal supply and production data by countries are given. Finally, coal trade data are presented, broken down for hard coal, steam coal, coking coal (imports and export). (R.P.)

  17. Experimental Investigation of Thermal Characteristics of Kiwira Coal Waste with Rice Husk Blends for Gasification

    Directory of Open Access Journals (Sweden)

    Deodatus Kazawadi

    2014-01-01

    Full Text Available Eminent depletion of fossil fuels and environmental pollution are the key forces driving the implementation cofiring of fossil fuels and biomass. Cogasification as a technology is known to have advantages of low cost, high energy recovery, and environmental friendliness. The performance/efficiency of this energy recovery process substantially depends on thermal properties of the fuel. This paper presents experimental study of thermal behavior of Kiwira coal waste/rice husks blends. Compositions of 0, 20, 40, 60, 80, and 100% weight percentage rice husk were studied using thermogravimetric analyzer at the heating rate of 10 K/min to 1273 K. Specifically, degradation rate, conversion rate, and kinetic parameters have been studied. Thermal stability of coal waste was found to be higher than that of rice husks. In addition, thermal stability of coal waste/rice husk blend was found to decrease with an increase of rice husks. In contrast, both the degradation and devolatilization rates increased with the amount of rice husk. On the other hand, the activation energy dramatically reduced from 131 kJ/mol at 0% rice husks to 75 kJ/mol at 100% rice husks. The reduction of activation energy is advantageous as it can be used to design efficient performance and cost effective cogasification process.

  18. Large reservoirs: Chapter 17

    Science.gov (United States)

    Miranda, Leandro E.; Bettoli, Phillip William

    2010-01-01

    expressed effects, such as turbidity and water quality, zooplankton density and size composition, or fish growth rates and assemblage composition, are the upshot of large-scale factors operating outside reservoirs and not under the direct control of reservoir managers. Realistically, abiotic and biotic conditions in reservoirs are shaped by factors working inside and outside reservoirs, with the relative importance of external factors differing among reservoirs. With this perspective, large reservoirs are viewed from a habitat standpoint within the framework of a conceptual model in which individual reservoir characteristics are influenced by both local- and landscape-scale factors (Figure 17.1). In the sections that follow, how each element of this hierarchical model influences habitat and fish assemblages in reservoirs is considered. Important in-reservoir habitat issues and reservoirs as part of larger systems, where reservoir management requires looking for real solutions outside individual reservoirs are described.

  19. The Variation Characteristic of Sulfides and VOSc in a Source Water Reservoir and Its Control Using a Water-Lifting Aerator

    Directory of Open Access Journals (Sweden)

    Jian-Chao Shi

    2016-04-01

    Full Text Available Sulfides and volatile organic sulfur compounds (VOSc in water are not only malodorous but also toxic to humans and aquatic organisms. They cause serious deterioration in the ecological environment and pollute drinking water sources. In the present study, a source water reservoir—Zhoucun Reservoir in East China—was selected as the study site. Through a combination of field monitoring and in situ release experiments of sulfides, the characteristics of seasonal variation and distribution of sulfides and VOSc in the reservoir were studied, and the cause of the sulfide pollution was explained. The results show that sulfide pollution was quite severe in August and September 2014 in the Zhoucun Reservoir, with up to 1.59 mg·L−1 of sulfides in the lower layer water. The main source of sulfides is endogenous pollution. VOSc concentration correlates very well with that of sulfides during the summer, with a peak VOSc concentration of 44.37 μg·L−1. An installed water-lifting aeration system was shown to directly oxygenate the lower layer water, as well as mix water from the lower and the upper layers. Finally, the principle and results of controlling sulfides and VOSc in reservoirs using water-lifting aerators are clarified. Information about sulfides and VOSc fluctuation and control gained in this study may be applicable to similar reservoirs, and useful in practical water quality improvement and pollution prevention.

  20. Clinical X-ray characteristics of chronic bronchitis in workers of coal mines

    International Nuclear Information System (INIS)

    Sokolik, L.I.; Shumakov, A.V.; Doroshenko, A.N.

    1988-01-01

    100 workers of coal mines with chronic dusty bronchitis are examined. The roentgenological manifestations of different stages of the diseases with respect to the clinical picture and function of external breath according to the data of roentgenopneumopolygraphy, are characterized. The attention is paid to a most pronounced violation of external breath function in this category of patients. The peculiarities of clinico-roentgenological picture of dust bronchitis found should be taken into account when solving the problems of medical labor examination. 8 refs.; 3 figs

  1. Characteristics of an open-cut coal mine fire pollution event

    Science.gov (United States)

    Reisen, Fabienne; Gillett, Rob; Choi, Jason; Fisher, Gavin; Torre, Paul

    2017-02-01

    On 9 February 2014, embers from a nearby grass/shrub fire spotted into an unused part of the Hazelwood open-cut brown coal mine located in the Latrobe Valley of Victoria, Australia and started a fire that spread rapidly and extensively throughout the mine under strong south-westerly winds and burned over a period of 45 days. The close proximity of the town to the coal mine and the low buoyancy of the smoke plume led to the accumulation of dense smoke levels in the township of Morwell (population of 14,000) particularly under south-westerly winds. A maximum daily PM2.5 concentration of 731 μg m-3 and 8-h CO concentration of 33 ppm were measured at Morwell South, the closest residential area located approximately 500 m from the mine. These concentrations were significantly higher than national air quality standards. Air quality monitoring undertaken in the Latrobe Valley showed that smoke from the Hazelwood mine fire affected a wide area, with particle air quality standards also exceeded in Traralgon (population of 25,000) located approximately 13 km from the mine. Pollutant levels were significantly elevated in February, decreased in March once the fire abated and then returned to background levels once the fire was declared safe at the end of March. While the smoke extent was of a similar order of magnitude to other major air pollution events worldwide, a closer look at emissions ratios showed that the open combustion of lignite brown coal in the Hazelwood mine was different to open combustion of biomass, including peat. It suggested that the dominant combustion process was char combustion. While particle and carbon monoxide monitoring started approximately 4 days after the fire commenced when smoke levels were very high, targeted monitoring of air toxics only began on 26 February (17 days after the fire) when smoke levels had subsided. Limited research on emission factors from open-cut coal mine fires make it difficult to assess the likely concentrations of air

  2. Testing the electrostatic characteristics of polypropylene fabric with metallic yarns, intended for use in coal mines threatened by the explosion hazard. Part 2: Tests in coal mine

    International Nuclear Information System (INIS)

    Talarek, M; Orzech, L

    2011-01-01

    The aim of this paper was to assess the electrostatic safety of polypropylene fabric with metallic yarns intended for use in coal mines. Such fabrics have not been used in the Polish mining industry yet. The tests conducted have been divided into two subgroups: laboratory tests and tests in a coal mine. This paper presents the results of tests in a coal mine, where we have focused on the resistance-to-ground in some specific situations. Bags made of fabric at the roadway face were tested, as well as the roll of fabric during transport and carried by a miner. The results obtained allow the reliable assessment of the risk of using fabrics with metallic yarns in the explosive atmosphere which often occurs in coal mines.

  3. Coal Reservoir Physical Property Features and CBM Resource Potential in Xingtai Coal-bearing Region%邢台含煤区煤储层物性特征及煤层气资源潜力

    Institute of Scientific and Technical Information of China (English)

    高亮; 上官拴通; 张国斌; 李英英; 闫家栋

    2017-01-01

    为了评价邢台含煤区煤层气开发潜力,采集不同矿井的2、8、9号煤样进行了煤岩组分、孔裂隙分布、等温吸附及水单相渗透率实验分析,采用体积法和综合排队系数法对底板标高-2000 m以浅的煤层气资源量进行了预测和评价.结果表明:区内目的煤层厚度、煤级适中,具有较好的生储条件;煤岩的镜质组、惰质组和壳质组含量依次减少,水分随煤化程度的增加呈现先减小后增大,挥发分随煤化程度的增加而减少;孔隙度随煤化程度增大而增大,且孔径分布不均匀,微孔的孔容和比表面积所占比例最大;显微裂隙密度级别为一级,部分裂隙被脉状方解石和粒状黄铁矿充填;煤的吸附量受煤级控制,且在一定压力范围内,吸附量随压力增加而增大,吸附能力随压力增加而减小;煤层渗透率离散性较大,属中~高级渗透率.估算底板标高-2000 m以浅潜在的煤层气资源量为427.31亿m3,优选出中等有利区块6个,其中FY区、QHY区、GZ区为煤层气勘探首选区块.%To assess CBM exploitation potential in the Xingtai coal-bearing region, collected coal samples from coal seam Nos. 2, 8 and 9 in different coalmines, carried out experimental analysis of coal lithotype, pore and fissure distribution, isothermal adsorption and wa-ter single-phase permeability. Through the volumetric method and integrated queuing coefficient method carried out prediction and as-sessment of CBM resources above floor elevation-2000 m. The result has shown that the target coal thickness and coal rank are moder-ate, thus have better CBM generation and preservation conditions. Contents of coal macerals vitrinite, inertinite and exinite are sequen-tially deceasing;moisture content increasing along with coalification degree increasing presents deceasing first than increasing;volatile matter decreasing along with coalification degree increasing. Porosity is increasing along with coalification

  4. Influence of the shape of soaring particle based on coal-water slurry containing petrochemicals on ignition characteristics

    Directory of Open Access Journals (Sweden)

    Valiullin Timur R.

    2017-01-01

    Full Text Available This paper examines the laws of stable ignition of organic coal-water slurry containing petrochemicals (CWSP. The CWSP is based on the filter cake of coal and scavenge oil. The experiments are performed for individual CWSP particles soaring in a special set-up. The temperature and velocity of an oxidizer flow are varied between 500-1200 K, and 0.5-3 m/s. The dimensions (longitudinal and transverse of particles range are from 0.5 mm to 5 mm. The study indicates how the shape of a fuel particle (sphere, ellipsoid, and polyhedron influences its ignition characteristics (delay time, minimum temperature, modes, stages. Based on the experimental results, the paper explains why the surface configuration of particles influences the conditions of heat transfer with an oxidizer. The results obtained for soaring particles are compared with the results for fixed CWSP particles having different surface configurations (sphere, ellipsoid, and polyhedron. In general, the study may contribute to the expansion of the fuel resource base. The experimental data may be used for the development of the technologies of burning CWSP prepared by recycling traditional fuels. As a result of this study, several recommendations for the practical application of research results are made.

  5. Investigations into stress shell characteristics of surrounding rock in fully mechanized top-coal caving face

    Energy Technology Data Exchange (ETDEWEB)

    Xie, G.X.; Chang, J.C.; Yang, K. [Anhui University of Science and Technology, Huainan (China)

    2009-01-15

    A key issue in underground mining is to understand and master the evolving patterns of stress induced by mining, and to control and utilize the action of rock pressure. Numerical and physical modeling tests have been carried out to investigate the distribution patterns of stress in the rock surrounding a fully mechanized top-coal caving (FMTC) face. The results showed that a macro-stress shell composed of high stress exists in the rock surrounding an FMTC face. The stress of the shell is higher than its internal and external stress and the stresses at its skewback producing abutment pressure for the surrounding rock. The stress shell lies in the virgin coal and rock mass in the vicinity of the face and its sagging zone. The stress shell, which bears and transfers the loads of overlying strata, acts as the primary supporting system of forces, and is the corpus of characterizing three-dimensional and macro-rock pressure distribution of mining face. Its external and internal shape changes with the variations in the working face structure as the face advances. Within the low-stress zone inside the stress shell, another structure, i.e. voussoir beam, which only bears parts of the load from the lower-lying strata, will produce periodic pressures on the face instead of great dynamic pressure even if the beam ruptures and loses stability. The results show that the FMTC face is situated within the lower-stress zone, which is protected by the stress shell of the overlying surrounding rock. We give an explanation of lower occurrence of rock pressure on FMTC faces, and reveal the mechanical nature of the top coal of an FMTC face acting as a 'cushion'. The strata behaviors of the face and its neighboring gates are under control of the stress shell. Drastic rock pressure in mine may occur when the balance of the stress shell is destruction or the forces system of the stress shell transfers. Crown Copyright

  6. Fortescue reservoir development and reservoir studies

    Energy Technology Data Exchange (ETDEWEB)

    Henzell, S.T.; Hicks, G.J.; Horden, M.J.; Irrgang, H.R.; Janssen, E.J.; Kable, C.W.; Mitchell, R.A.H.; Morrell, N.W.; Palmer, I.D.; Seage, N.W.

    1985-03-01

    The Fortescue field in the Gippsland Basin, offshore southeastern Australia is being developed from two platforms (Fortescue A and Cobia A) by Esso Australia Ltd. (operator) and BHP Petroleum. The Fortescue reservoir is a stratigraphic trap at the top of the Latrobe Group of sediments. It overlies the western flank of the Halibut and Cobia fields and is separated from them by a non-net sequence of shales and coals which form a hydraulic barrier between the two systems. Development drilling into the Fortescue reservoir commenced in April 1983 with production coming onstream in May 1983. Fortescue, with booked reserves of 44 stock tank gigalitres (280 million stock tank barrels) of 43/sup 0/ API oil, is the seventh major oil reservoir to be developed in the offshore Gippsland Basin by Esso/BHP. In mid-1984, after drilling a total of 20 exploration and development wells, and after approximately one year of production, a detailed three-dimensional, two-phase reservoir simulation study was performed to examine the recovery efficiency, drainage patterns, pressure performance and production rate potential of the reservoir. The model was validated by history matching an extensive suite of Repeat Formation Test (RFT) pressure data. The results confirmed the reserves basis, and demonstrated that the ultimate oil recovery from the reservoir is not sensitive to production rate. This result is consistent with studies on other high quality Latrobe Group reservoirs in the Gippsland Basin which contain undersaturated crudes and receive very strong water drive from the Basin-wide aquifer system. With the development of the simulation model during the development phase, it has been possible to more accurately define the optimal well pattern for the remainder of the development.

  7. Influence of Land Use and Watershed Characteristics on Protozoa Contamination in a Potential Drinking Water Resources Reservoir

    Science.gov (United States)

    Relative changes in the microbial quality of Lake Texoma, on the border of Texas and Oklahoma, were investigated by monitoring protozoan pathogens, fecal indicators, and factors influencing the intensity of the microbiological contamination of surface water reservoirs. The waters...

  8. Microstructural characteristics of toluene and quinoline-insolubles from coal-tar pitch and their cokes

    Energy Technology Data Exchange (ETDEWEB)

    Panaitescu, C. [University POLITEHNICA Bucharest, Faculty of Industrial Chemistry, Fuel Laboratory, Polizu St. 1, Sector 1, 011061, Bucharest (Romania); Predeanu, G. [Metallurgical Research Institute, Department of Raw Materials, Mehadia St. 39, Sector 6, 060543 Bucharest (Romania)

    2007-08-01

    The structural composition of coal-tar pitch used in the preparation of the special binder-pitch, was determined with special emphasis on the optical properties of the {beta}-resins, as typical components necessary to obtain electrodes of best quality through the pyrogenetic processes of baking and graphitization. In addition to raw toluene- and quinoline-insolubles (TI, QI), the corresponding cokes were analysed to evaluate, by structural composition and microtexture, the behaviour of pitch fractions during carbonization. The results suggest the dependence of the texture development on the type of toluene- and quinoline-insolubles and {beta}-resins during processing conditions, which influence the mesophase formation. An original and important result of the carbopetrographical study is represented by the identification and evaluation of {beta}-resins in the coke texture. (author)

  9. Production Characteristics and Reservoir Quality at the Ivanić Oil Field (Croatia) Predicted by Machine Learning System

    OpenAIRE

    Hernitz, Zvonimir; Đureković, Miro; Crnički, Josip

    1996-01-01

    At the Ivanić oil field, hydrocarbons are accumulated in fine tomedium grained litharenits of the Ivanić-Grad Formation (Iva-sandstones member) of Upper Miocene age. Reservoir rocks are dividedinlo eight depositional (production) units (i1- i8). Deposits of eachunit are characterized by their own reservoir quality parameters(porosity, horizontal permeability, net pay ... ). Production characteristicsof 30 wells have been studied by a simple slatistical method. Twomajor production well ca...

  10. THE LEVEL OF HYDROBIONT DEVELOPMENT AS A CHARACTERISTIC OF THE CONDITIONS OF FISH FATTENING IN THE DNIEPER RESERVOIRS

    Directory of Open Access Journals (Sweden)

    S. Kruzhylina

    2015-12-01

    Full Text Available Purpose. To investigate qualitative and quantitative indicators of the development of phyto-, zooplankton and macrozoobenthos. To assess bioproductional capacity and potential fish productivity of the Dnieper reservoirs at the current stage of development (2011–2013. Methodology. The materials were collected across the entire area of the reservoirs according to standard net-station. Collection and processing of the materials were carried out based on generally accepted hydrobiological methods. Findings. The current state of fish forage resources and productional capacity of Dnieper reservoirs based on the development of phyto-, zooplankton and macrozoobenthos has been investigated. Qualitative and quantitative indicators of the development of phyto-, zooplankton and macrozoobenthos for 2011–2013 have been shown. During the study period, total production varied from 5 to 15 thousand kg/ha that can ensure the potential fish production in the reservoirs of approx. 21–62 kg/ha. It was found that zooplanktonic and macrozoobenthic communities play the predominant role in forming the fish productivity in the reservoirs even with their low level of development. The value of the potential fish productivity in the reservoirs is formed of 14–60% by zooplanktonic communities, 3–23% by soft zoobenthos production, 21–51% by mollusks, and 9–33% by phytoplanktonic communities. Originality. The qualitative and quantitative indicators of the development of phyto-, zooplankton and macrozoobenthos and to assess potential bioproductional capacity of the Dnieper reservoirs at the current stage of development (2011–2013 have been investigated. Practical value. The obtained results offer an opportunity to assess the productional capacity of the Dnieper reservoirs and can be used for the development of scientifically sound background for stocking them with commercially valuable fish species for their rational exploitation that is a priority task of

  11. Quantifying the uncertainties of climate change effects on the storage-yield and performance characteristics of the Pong multi-purpose reservoir, India

    Directory of Open Access Journals (Sweden)

    B. Soundharajan

    2015-06-01

    Full Text Available Climate change is predicted to affect water resources infrastructure due to its effect on rainfall, temperature and evapotranspiration. However, there are huge uncertainties on both the magnitude and direction of these effects. The Pong reservoir on the Beas River in northern India serves irrigation and hydropower needs. The hydrology of the catchment is highly influenced by Himalayan seasonal snow and glaciers, and Monsoon rainfall; the changing pattern of the latter and the predicted disappearance of the former will have profound effects on the performance of the reservoir. This study employed a Monte-Carlo simulation approach to characterise the uncertainties in the future storage requirements and performance of the reservoir. Using a calibrated rainfall-runoff (R-R model, the baseline runoff scenario was first simulated. The R-R inputs (rainfall and temperature were then perturbed using plausible delta-changes to produce simulated climate change runoff scenarios. Stochastic models of the runoff were developed and used to generate ensembles of both the current and climate-change perturbed future scenarios. The resulting runoff ensembles were used to simulate the behaviour of the reservoir and determine "populations" of reservoir storage capacity and performance characteristics. Comparing these parameters between the current and the perturbed provided the population of climate change effects which was then analysed to determine the uncertainties. The results show that contrary to the usual practice of using single records, there is wide variability in the assessed impacts. This variability or uncertainty will, no doubt, complicate the development of climate change adaptation measures; however, knowledge of its sheer magnitude as demonstrated in this study will help in the formulation of appropriate policy and technical interventions for sustaining and possibly enhancing water security for irrigation and other uses served by Pong reservoir.

  12. Spot testing on mechanical characteristics of surrounding rock in gates of fully mechanized top-coal caving face

    Energy Technology Data Exchange (ETDEWEB)

    Xie Guang-xiang; Yang Ke; Chang Ju-cai [Anhui University of Science and Technology, Anhui (China). Department of Resource Exploration and Management Engineering

    2006-07-01

    The distribution patterns of mechanical characteristics for surrounding rock in the gateways of fully mechanized top-coal caving (FMTC) face were put forward by analyzing deep displacement, surface displacement, stress distribution and supports loading. The results show that the surrounding rock of the gateways lies in abutment pressure decrease zone near the working face, so that the support load decreases. But the deformations of supports and surrounding rock are very acute. The deformation of surrounding rock appears mainly in abutment pressure influence zone. Reasonable roadway supporting should control the deformation of surrounding rock in intense stage of mining influence. Supporting design ideas of tailentry and head entry should be changed from loading control to deformation control. 8 refs., 10 figs., 1 tab.

  13. Surface chemical characteristics of coal fly ash particles after interaction with seawater under natural deep sea conditions

    International Nuclear Information System (INIS)

    Brami, Y.; Shemesh, A.; Cohen, H.; Herut, B.

    1999-01-01

    The surface chemical characteristics of coal fly ash (CFA) before and after interaction with Mediterranean deep seawater was studied by X-ray photoelectron spectroscopy (XPS). Significantly lower values of Si, Ca, and S and higher values of Mg and Cl were found in the retrieved CFA as compared to fresh CFA. It is suggested that hydrolysis of the oxide matrixes results in an alkaline environment which rapidly leads to several chemical reactions. The two most important are (a) dissolution of the amorphous silicate and the calcium phases and (b) precipitation of Mg(OH) 2 -brucite. A depth profile of the retrieved CFA was measured by both line-shape analysis of the XPS spectra and by consecutive cycle of sputtering. The thickness of the brucite layer is estimated to be 1.3 nm

  14. Coal Matrix Deformation and Pore Structure Change in High-Pressure Nitrogen Replacement of Methane

    Directory of Open Access Journals (Sweden)

    Xiaofeng Ji

    2018-01-01

    Full Text Available Coal matrix deformation is one of the main controlling factors for coal reservoir permeability changes in nitrogen foam fracturing. The characteristics and mechanism of coal matrix deformation during the process of adsorption/desorption were studied by isothermal adsorption/desorption experiments with methane and nitrogen. Based on the free-energy theories, the Langmuir equation, and elastic mechanics, mathematical models of coal matrix deformation were developed and the deformation characteristics in adsorption/desorption processes were examined. From the study, we deduced that the coal matrix swelling, caused by methane adsorption, was a Langmuir-type relationship with the gas pressure, and exponentially increased as the adsorption quantity increased. Then, the deformation rate and amplitude of the coal matrix decreased gradually with the increase of the pressure. At the following stage, where nitrogen replaces methane, the coal matrix swelling continued but the deformation amplitude decreased, which was only 19.60% of the methane adsorption stage. At the mixed gas desorption stage, the coal matrix shrank with the reduction of pressure and the shrinkage amount changed logarithmically with the pressure, which had the hysteresis effect when compared with the swelling in adsorption. The mechanism of coal matrix deformation was discussed through a comparison of the change of micropores, mesopores, and also part macropores in the adsorption process.

  15. [Spatial Distribution Characteristics of Different Species Mercury in Water Body of Changshou Lake in Three Gorges Reservoir Region].

    Science.gov (United States)

    Bai, Wei-yang; Zhang, Cheng; Zhao, Zheng; Tang, Zhen-ya; Wang, Ding-yong

    2015-08-01

    An investigation on the concentrations and the spatial distribution characteristics of different species of mercury in the water body of Changshou Lake in Three Gorges Reservoir region was carried out based on the AreGIS statistics module. The results showed that the concentration of the total mercury in Changshou Lake surface water ranged from 0.50 to 3.78 ng x L(-1), with an average of 1.51 ng x L(-1); the concentration of the total MeHg (methylmercury) ranged from 0.10 to 0.75 ng x L(-1), with an average of 0.23 ng x L(-1). The nugget effect value of total mercury in surface water (50.65%), dissolved mercury (49.80%), particulate mercury (29.94%) and the activity mercury (26.95%) were moderate spatial autocorrelation. It indicated that the autocorrelation was impacted by the intrinsic properties of sediments (such as parent materials and rocks, geological mineral and terrain), and on the other hand it was also disturbed by the exogenous input factors (such as aquaculture, industrial activities, farming etc). The nugget effect value of dissolved methylmercury (DMeHg) in Changshou lake surface water (3.49%) was less than 25%, showing significant strong spatial autocorrelation. The distribution was mainly controlled by environmental factors in water. The proportion of total MeHg in total Hg in Changshou Lake water reached 30% which was the maximum ratio of the total MeHg to total Hg in freshwater lakes and rivers. It implied that mercury was easily methylated in the environment of Chanashou Lake.

  16. Pollution characteristics and ecological risk assessment of heavy metals in the surface sediments from a source water reservoir

    Directory of Open Access Journals (Sweden)

    Changming Yang

    2016-10-01

    Full Text Available Surface sediment samples were collected from a source water reservoir in Zhejiang Province, East of China to investigate pollution characteristics and potential ecological risk of heavy metals. The BCR sequential extraction method was used to determine the four chemical fractions of heavy metals such as acid soluble, easily reducible, easily oxidizable and residual fractions. The heavy metals pollution and potential ecological risk were evaluated systematically using geoaccumulation index (Igeo and Hakanson potential ecological risk index (H′. The results showed that the sampling sites from the estuaries of tributary flowing through downtowns and heavy industrial parks showed significantly (p < 0.05 higher average concentrations of heavy metals in the surface sediments, as compared to the other sampling sites. Chemical fractionation showed that Mn existed mainly in acid extractable fraction, Cu and Pb were mainly in reducible fraction, and As existed mainly in residual fraction in the surface sediments despite sampling sites. The sampling sites from the estuary of tributary flowing through downtown showed significantly (p < 0.05 higher proportions of acid extractable and reducible fractions than the other sampling sites, which would pose a potential toxic risk to aquatic organisms as well as a potential threat to drinking water safety. As, Pb, Ni and Cu were at relatively high potential ecological risk with high Igeo values for some sampling locations. Hakanson potential ecological risk index (H′ showed the surface sediments from the tributary estuaries with high population density and rapid industrial development showed significantly (p < 0.05 higher heavy metal pollution levels and potential ecological risk in the surface sediments, as compared to the other sampling sites.

  17. Washability of Australian coals

    Energy Technology Data Exchange (ETDEWEB)

    Whitmore, R L

    1979-06-01

    Australian coals tend to be young in geological age and high in ash by world standards; preparation of the coal before marketing is almost universal. On the basis of float and sink data from 39 locations in the eastern Australian coalfields, the coals are place in four categories representing increasing difficulty in their washability characteristics. These seem to be related neither to the geological age nor the geographical position of the deposit and Hunter Valley coals, for example, span all categories. The influence of crushing on the washability of Australian coals is briefly considered and from limited data it is concluded to be appreciably smaller than for British or North American coals. A strategy for the float and sink analysis of Australian coals is proposed and the influence of washability characteristics on current trends in the selection of separating processes for coking and steaming products is discussed.

  18. Types and characteristics of carbonate reservoirs and their implication on hydrocarbon exploration: A case study from the eastern Tarim Basin, NW China

    Directory of Open Access Journals (Sweden)

    Shiwei Huang

    2017-02-01

    Full Text Available Carbonate rocks are deposited in the Ordovician, Cambrian, and Sinian of eastern Tarim Basin with a cumulative maximum thickness exceeding 2000 m. They are the main carriers of oil and gas, and a great deal of natural gas has been found there in the past five years. Based on lithofacies and reservoir differences, natural gas exploration domains of eastern Tarim Basin can be classified into five types: Ordovician platform limestone; Ordovician platform dolomite; Cambrian platform margin mound shoal; Cambrian slope gravity flow deposits, and; Sinian dolomite. Carbonate reservoir characteristics of all the types were synthetically analyzed through observation on drilling core and thin sections, porosity and permeability measurement, and logging data of over 10 drilling wells. We find distribution of part of good fracture and cave reservoir in carbonate platform limestone of Ordovician. In the Ordovician, platform facies dolomite is better than limestone, and in the Cambrian, platform margin mound shoal dolomite has large stacking thickness. Good quality and significantly thick carbonate gravity deposit flow can be found in the Cambrian slope, and effective reservoir has also been found in Sinian dolomite. Commercial gas has been found in the limestone and dolomite of Ordovician in Shunnan and Gucheng areas. Exploration experiences from these two areas are instructive, enabling a deeper understanding of this scene.

  19. [Distribution characteristics of soil organic carbon under different forest restoration modes on opencast coal mine dump].

    Science.gov (United States)

    Wen, Yue-rong; Dang, Ting-hui; Tang, Jun; Li, Jun-chao

    2016-01-01

    The content and storage of soil organic carbon (SOC) were compared in six wood restoration modes and adjacent abandoned land on opencast coal mine dump, and the mechanisms behind the differences and their influencing factors were analyzed. Results showed that the contents of SOC in six wood lands were significantly higher (23.8%-53.2%) than that of abandoned land (1.92 g · kg⁻¹) at 0-10 cm soil depth, the index were significantly higher (5.8%-70.4%) at 10-20 cm soil depth than the abandoned land (1.39 g · kg⁻¹), and then the difference of the contents of SOC in the deep soil (20-100 cm) were not significant. The contents of SOC decreased with increase of soil depth, but the decreasing magnitude of the topsoil (0-20 cm) was higher than that of the deep soil (20-100 cm). Compared with the deep soil, the topsoil significant higer storage of SOC in different woods, the SOC storage decreased with the soil depth. Along the 0-100 cm soil layer, the storage of SOC in six wood lands higher (18.1%-42.4%) than that of the abandoned land (17.52 t · hm⁻²). The SOC storage of Amorpha fruticosa land (24.95 t · hm⁻²) was obviously higher than that in the other wood lands. The SOC storage in the shrub lands was 12.4% higher than that of the arbor woods. There were significantly positive correlations among forest litter, fine root biomass, soil water content and SOC on the dump. Consequently, different plantation restorations significantly improved the SOC level on the dump in 0-100 cm soil, especially the topsoil. But there was still a big gap about SOC level between the wood restoration lands and the original landform. To improve the SOC on opencast coal mine dump, A. fruticosa could be selected as the main wood vegetation.

  20. Adsorption characteristics of Cs"+ onto artificial zeolites synthesized from coal fly ash and diatomite

    International Nuclear Information System (INIS)

    Johan, Erni; Yoshida, Kohei; Itagaki, Yoshiteru; Aono, Hiromichi; Munthali, Moses Wazingwa; Matsue, Naoto

    2015-01-01

    The radioactive decontamination of water, soil and other materials requires cheap and effective adsorbents. Artificial zeolites synthesized from an industrial waste (coal fly ash: Na-P1 type zeolite) and a natural material (diatomite: mordenite type zeolite) have a high Cs"+ adsorptivity in the adsorption experiments using 0.1 g of the zeolite and 50 mL of up to 7.5 mM CsCl. The coexisting cation suppressed the Cs"+ adsorption onto the zeolites, and the effect of the suppression was in the order, K"+ > Na"+ > Ca"2"+ > Mg"2"+. A thermodynamic analysis proved that the Cs"+ adsorption onto the two zeolites was exothermic favoring a lower temperature. The artificial mordenite showed a greater Cs"+ adsorption strength, higher distribution coefficient and lower ΔG°, especially at low Cs"+ concentrations. Adsorption isotherm analysis by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models showed a greater Cs"+ adsorption selectivity for the artificial mordenite even at a low pH. (author)

  1. Experimental Investigation into the Combustion Characteristics on the Co-firing of Biomass with Coal as a Function of Particle Size and Blending Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Lkhagvadorj, Sh; Kim, Sang In; Lim, Ho; Kim, Seung Mo; Jeon, Chung Hwan [Pusan National Univ., Busan (Korea, Republic of); Lee, Byoung Hwa [Doosan Heavy Industries and Construction, Ltd., Changwon (Korea, Republic of)

    2016-01-15

    Co-firing of biomass with coal is a promising combustion technology in a coal-fired power plant. However, it still requires verifications to apply co-firing in an actual boiler. In this study, data from the Thermogravimetric analyzer(TGA) and Drop tube furnace(DTF) were used to obtain the combustion characteristics of biomass when co-firing with coal. The combustion characteristics were verified using experimental results including reactivity from the TGA and Unburned carbon(UBC) data from the DTF. The experiment also analyzed with the variation of the biomass blending ratio and biomass particle size. It was determined that increasing the biomass blending ratio resulted in incomplete chemical reactions due to insufficient oxygen levels because of the rapid initial combustion characteristics of the biomass. Thus, the optimum blending condition of the biomass based on the results of this study was found to be 5 while oxygen enrichment reduced the increase of UBC that occurred during combustion of blended biomass and coal.

  2. Safety-technical characteristics of biomass, coal and straw. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wilen, C.; Rautalin, A.

    1995-12-31

    Safety-technical factors related to spontaneous ignition and dust explosions of biomasses were investigated. Parametres of dust explosions and effect of inertisation on the maximum pressure (pmax) and the maximum rate of pressure rise (Kstmax) were studied at elevated initial pressure (1-9 bar). The level of inertisation required to prevent dust explosions totally was determined at different initial pressures. The sensitivity of fuels to spontaneous ignition and the effect of pressure on the sensitivity to and temperature of spontaneous ignition were studied on a pressurised dynamic self-ignition equipment. The effect of inertisation on the self-ignition temperature and alternatives of preventing spontaneous ignition by effective inertisation in the pressure ranges of 1 and 25 bar were investigated. As an example of application, results obtained with the laboratory test equipment were extrapolated to bin sizes used in practice. As a factor contributing to spontaneous ignition, the flowability of different fuels in bins and lock-hoppers (stagnant fuel layers are especially sensitive to spontaneous ignition) in continuous flow and in flow stopped for a storage time of 1 hour was also studied. Walker`s rotating ring shear equipment and Jenike`s linear shear equipment based on shearing the fuel were used in the flowability measurements. The effect of fuel temperature (22 deg C, 40 deg C) on flowability was determined for forest residue chips. Dynamic friction coefficients between fuels and handling equipment were determined for stainless steel and rusty metal surface. As an example of application, results obtained with laboratory test equipment were extrapolated to a bin size of 21 m{sup 3} by calculating the size of the minimum discharge opening required by mass flow of different coals and forest residue chips and the minimum angle of repose of the conical part for a bin of stainless steel

  3. Safety-technical characteristics of biomass, coal and straw. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wilen, C; Rautalin, A

    1996-12-31

    Safety-technical factors related to spontaneous ignition and dust explosions of biomasses were investigated. Parametres of dust explosions and effect of inertisation on the maximum pressure (pmax) and the maximum rate of pressure rise (Kstmax) were studied at elevated initial pressure (1-9 bar). The level of inertisation required to prevent dust explosions totally was determined at different initial pressures. The sensitivity of fuels to spontaneous ignition and the effect of pressure on the sensitivity to and temperature of spontaneous ignition were studied on a pressurised dynamic self-ignition equipment. The effect of inertisation on the self-ignition temperature and alternatives of preventing spontaneous ignition by effective inertisation in the pressure ranges of 1 and 25 bar were investigated. As an example of application, results obtained with the laboratory test equipment were extrapolated to bin sizes used in practice. As a factor contributing to spontaneous ignition, the flowability of different fuels in bins and lock-hoppers (stagnant fuel layers are especially sensitive to spontaneous ignition) in continuous flow and in flow stopped for a storage time of 1 hour was also studied. Walker`s rotating ring shear equipment and Jenike`s linear shear equipment based on shearing the fuel were used in the flowability measurements. The effect of fuel temperature (22 deg C, 40 deg C) on flowability was determined for forest residue chips. Dynamic friction coefficients between fuels and handling equipment were determined for stainless steel and rusty metal surface. As an example of application, results obtained with laboratory test equipment were extrapolated to a bin size of 21 m{sup 3} by calculating the size of the minimum discharge opening required by mass flow of different coals and forest residue chips and the minimum angle of repose of the conical part for a bin of stainless steel

  4. Hydrogenolysis reactions characteristics of deashed coal under low temperature; Teionka ni okeru dakkai shoritan no suisoka bunkai hanno tokusei

    Energy Technology Data Exchange (ETDEWEB)

    Owada, T.; Mashimo, K.; Wainai, T. [Nihon University, Tokyo (Japan). College of Science and Technology

    1996-10-28

    In relation to coal liquefaction, the effect of inorganic minerals on liquefaction reactivity and the effect of hydrofluoric acid (HF) treatment on organic molecular structure of coals were studied by demineralization of low-rank coals in HCl or HF solution. In experiment, Taiheiyo coal specimen was deashed in HCl solution at 25-70{degree}C for 6 hours while agitating, and in addition, deashed in HF solution. Hydrogenolysis of the deashed coal specimen was conducted using tetralin or methylnaphthalene as solvent under initial hydrogen pressure of 1.96MPa at reaction temperature of 693K for 60min. The experimental results are as follows. The ash content of Taiheiyo coal hardly offers catalysis in hydrogenolysis reaction. Carboxyl group increases in demineralization of coal because of breakage of bridged bonds. Organic structure of coal changes by demineralization in dense HF solution. Change in organic structure of coal by demineralization in dense HF solution is dependent on treatment temperature. 2 refs., 4 figs., 1 tab.

  5. Organic geochemical characteristics and paleoclimate conditions of the Miocene coals at the Çan-Durali (Çanakkale)

    Science.gov (United States)

    Hoş-Çebi, Fatma

    2017-05-01

    In this study, n-alkane and isoprenoid, saturated and aromatic biomarker distributions of Miocene coals in the Çan (Çanakkale) region, were studied to investigate organic geochemical characteristics, depositional environment, and hydrocarbon potential of these coals. Çan formation (Middle Miocene) unconformably overlies the basement Çan volcanites (Upper Oligocene-Lower Miocene). This formation is composed of lignite, clayey lignite, and ligniferous clayey levels of various thicknesses interlayering with clay and tuffite. The formation represents sediments of small lacustrine basins that are isolated by faults that are formed contemporaneously with Early-Middle Eocene volcanism. Coaliferous units are overlain by lower agglomerate levels. The Rock Eval analyses show that the average TOC (Total Organic Carbon) content of the coal is 53.71% and the average HI (Hydrogen Index) value is 180.5 mgHC/gTOC. OI (Oxygen Index) values (avg. 22.33 mgCO2/gTOC) show that the depositional environment of peat deposits is suboxic. According to HI-Tmax, S2-TOC classification diagrams and Pr/n-C17vs. Ph/n-C18 diagram, the organic matter is composed of Type II and Type III kerogen mixing and represents a transitional environment. In gas chromatograms, n-alkanes with high, mostly odd-numbered carbons are dominant and they are associated with a slight algal contribution. CPI22-30 (Carbon Preference Index) and TARHC (Terrigenous/Aquatic Ratio) values indicate a dominance of high-carbon numbered n-alkanes, indicating the presence of terrestrial organic matter. Paq (aquatic plant n-alkane proxy) values (0.2; 0.3) indicate a climate with relatively wet conditions or low precipitation, the presence of emergent macrophyteses, and the scarcity of hydrophilic plants. Pwax (vascular plant n-alkane proxy) ratio (0.8; 0.7) shows moderately wet conditions and a relatively low water level. The TOC, ACL (n-alkane average chain length), Qwood/grass, Qwood/plant, and Qgrass/plant values indicate the

  6. Evaluation of coal bed methane potential of coal seams of Sawang ...

    Indian Academy of Sciences (India)

    This analysis shows that the maximum methane gas adsorbed in the coal sample CG-81 is 17 m3/t (Std. daf), at maximum pressure of 5.92 MPa ... vast coal reserves are ideal reservoirs for the gen- eration and accumulation of CBM. ... of gases in coal seams, such as, compression as free gas in the pore spaces, condensed ...

  7. Geochemical Characteristics of Trace Elements in the No. 6 Coal Seam from the Chuancaogedan Mine, Jungar Coalfield, Inner Mongolia, China

    Directory of Open Access Journals (Sweden)

    Lin Xiao

    2016-03-01

    Full Text Available Fourteen samples of No. 6 coal seam were obtained from the Chuancaogedan Mine, Jungar Coalfield, Inner Mongolia, China. The samples were analyzed by optical microscopic observation, X-ray diffraction (XRD, scanning electron microscope equipped with an energy-dispersive X-ray spectrometer (SEM-EDS, inductively coupled plasma mass spectrometry (ICP-MS and X-ray fluorescence spectrometry (XRF methods. The minerals mainly consist of kaolinite, pyrite, quartz, and calcite. The results of XRF and ICP-MS analyses indicate that the No. 6 coals from Chuancaogedan Mine are higher in Al2O3, P2O5, Zn, Sr, Li, Ga, Zr, Gd, Hf, Pb, Th, and U contents, but have a lower SiO2/Al2O3 ratio, compared to common Chinese coals. The contents of Zn, Sr, Li, Ga, Zr, Gd, Hf, Pb, Th, and U are higher than those of world hard coals. The results of cluster analyses show that the most probable carrier of strontium in the coal is gorceixite; Lithium mainly occurs in clay minerals; gallium mainly occurs in inorganic association, including the clay minerals and diaspore; cadmium mainly occurs in sphalerite; and lead in the No. 6 coal may be associated with pyrite. Potentially valuable elements (e.g., Al, Li, and Ga might be recovered as byproducts from coal ash. Other harmful elements (e.g., P, Pb, and U may cause environmental impact during coal processing.

  8. Self-scrubbing coal

    International Nuclear Information System (INIS)

    Kindig, J.K.

    1992-01-01

    More than 502 million tons - 65 percent of all coal shipped to utilities in 1990 - were above 1.2 pounds of sulfur dioxide per million Btu. Most of the coal, even though cleaned in conventional coal preparation plants, still does not meet the emission limitation the Clean Air Act Amendments mandate for the year 2000. To cope with this fact, most utilities plan to switch to low sulfur (western U.S. or Central Appalachian) coal or install scrubbers. Both solutions have serous drawbacks. Switching puts local miners out of work and weakens the economy in the utility's service territory. Scrubbing requires a major capital expenditure by the utility. Scrubbers also increase the operating complexity and costs of the generating station and produce yet another environmental problem, scrubber sludge. Employing three new cost-effective technologies developed by Customer Coals International (CCl), most non-compliance coals east of the Mississippi River can be brought into year-2000 compliance. The compliance approach employed, depends upon the characteristics of the raw coal. Three types of raw coal are differentiated, based upon the amount of organic sulfur in the coals and the ease (or difficultly) of liberating the pyrite. They are: Low organic sulfur content and pyrite that liberates easily. Moderate organic sulfur content and pyrite that liberates easily. High organic sulfur content or the pyrite liberates with difficulty. In this paper examples of each type of raw coal are presented below, and the compliance approach employed for each is described. The names of the beneficiated coal products produced from each type of raw coal give above are: Carefree Coal, Self-Scrubbing Coal and Dry-Scrubbing Coal

  9. Upper Paleozoic coal measures and unconventional natural gas systems of the Ordos Basin, China

    Directory of Open Access Journals (Sweden)

    Xuan Tang

    2012-11-01

    Full Text Available Upper Paleozoic coal measures in the Ordos Basin consist of dark mudstone and coal beds and are important source rocks for gas generation. Gas accumulations include coal-bed methane (CBM, tight gas and conventional gas in different structural areas. CBM accumulations are mainly distributed in the marginal area of the Ordos Basin, and are estimated at 3.5 × 1012 m3. Tight gas accumulations exist in the middle part of the Yishan Slope area, previously regarded as the basin-centered gas system and now considered as stratigraphic lithologic gas reservoirs. This paper reviews the characteristics of tight gas accumulations: poor physical properties (porosity < 8%, permeability < 0.85 × 10−3 μm2, abnormal pressure and the absence of well-defined gas water contacts. CBM is a self-generation and self-reservoir, while gas derived from coal measures migrates only for a short distance to accumulate in a tight reservoir and is termed near-generation and near-reservoir. Both CBM and tight gas systems require source rocks with a strong gas generation ability that extends together over wide area. However, the producing area of the two systems may be significantly different.

  10. Studies of fracture network geometry of reservoir outcrop analogues from terrestrial lidar data: attempts to quantify spatial variations of fracture characteristics

    Science.gov (United States)

    Vsemirnova, E. A.; Jones, R. R.; McCaffrey, K. J. W.

    2012-04-01

    We describe studies analysing terrestrial lidar datasets of fracture systems from a range of reservoir analogues in clastic and carbonate lithologies that represent geological analogues of offshore hydrocarbon reservoirs for the UK continental shelf. As fracture networks (observed here from centimetre to kilometre scale) can significantly affect the permeability of a fractured reservoir, the definition of fracture network geometry at various scales has become an important goal of structural analysis. The main aim of the study has been to extend the investigation of fracture networks in order to quantify spatial variations in fracture parameters in a variety of lithologies. The datasets were pre-processed using RiSCAN PRO software, and then re-sampled and filtered to derive characteristics which are traditionally measured from outcrops, including size distributions, fracture spacing and clustering statistics. This type of analysis can significantly reduce the uncertainty associated with some field fracture network measurements. The digitised fracture networks datasets are then used to investigate various aspects of spatial heterogeneity. A series of fracture maps (joints and faults) were generated at different scales, and fracture trends were studied to test scale dependency of fracture orientations. Multiscale trend analysis was then applied to describe the trend structure of the fracture networks.

  11. Limnological characteristics of a reservoir in semiarid Northeastern Brazil subject to intensive tilapia farming (Orechromis niloticus Linnaeus, 1758

    Directory of Open Access Journals (Sweden)

    Luis Artur Valões Bezerra

    2014-03-01

    Full Text Available AIM: There is currently no consensus regarding the physical and chemical variability of tropical reservoirs. In semiarid Northeastern Brazil, reservoirs are among other things used for human consumption, industrial water supply and intensive fish farming, all of which can impact water quality. The objective of this study was to evaluate the physical and chemical variability of the water in Sítios Novos, a reservoir in semiarid Northeastern Brazil, comparing samples collected in areas of intensive tilapia (Oreochromis niloticus farming to samples from areas not directly impacted by aquaculture, in both the dry and the rainy season. METHODS: Between October 2010 and July 2011, data were collected on temperature, conductivity, pH, turbidity, salinity, chlorophyll a, dissolved oxygen, oxygen demand, total phosphorus and total nitrogen levels in the water column using a multiparametric probe at four different sampling locations. Physical and chemical differences between the four locations were evaluated with the Kruskal-Wallis (KW test and Dunn's post test, while the t test, followed by Welchʼs correction, was used to compare samples collected in different seasons. RESULTS: No influence of intensive aquaculture was detected when comparing sampling locations near fish farms (180C and 300C to locations not directly impacted by aquaculture (LIMN1, near the dam, and LIMN2, near the debouch of the São Gonçalo river. However, the sampling locations differed significantly (p<0.05 with regard to conductivity, pH, turbidity and chlorophyll a levels. CONCLUSIONS: The physical and chemical variability was greater between seasons than between locations when the data were analyzed with the t test. That analysis showed significant differences for 22 of 40 comparisons between the 10 physical and chemical parameters in the two seasons at the four sampling locations. In conclusion, the physical and chemical variability registered for the Sítios Novos reservoir

  12. Fish mercury development in relation to abiotic characteristics and carbon sources in a six-year-old, Brazilian reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Tuomola, Leena; Niklasson, Terese [Evolutionary Biology Centre and Department of Limnology, Uppsala University, Norbyvaegen 20, S-752 36 Uppsala (Sweden); Castro e Silva, Edinaldo de [Departamento de Quimica, Universidade Federal de Mato Grosso (UFMT), Av. Fernando C. Costa/sn, 78 090-900 Cuiaba-MT (Brazil); Hylander, Lars D. [Department of Earth Sciences, Air, Water and Landscape Science, Uppsala University, Villavaegen 16, S-752 36 Uppsala (Sweden)], E-mail: Lars.Hylander@hyd.uu.se

    2008-02-01

    Time series on fish mercury (Hg) development are rare for hydroelectric reservoirs in the tropics. In the central-western part of Brazil, a hydroelectric reservoir, called Lago Manso, was completed in 1999 after that background levels of fish Hg concentrations had been determined. The development for the first 3 years was studied in 2002. The objective of the present study was to determine development of fish Hg concentrations for a second three-year period after flooding. The bioaccumulation factor and certain abiotic and biotic factors, possibly affecting the availability and accumulation of Hg, were also examined. The results show that Hg levels in fish from Lago Manso have increased more than five times compared to the background levels observed before construction of the reservoir. At the same time, dissolved organic carbon has increased while dissolved oxygen has decreased indicating enhanced bioavailability of Hg. In the reservoir, Salminus brasiliensis had in average a Hg content of 1.1 {mu}g g{sup -1} f.w., Pseudoplatystoma fasciatum 1.2, Serrasalmus marginatus/spilopleura 0.9, and Brycon hilarii 0.6 {mu}g g{sup -1} f.w. The average fish Hg contents were higher downstream, except for B. hilarii. In the reservoir, the average Hg content of each species was in 2005 always over the consumption limit (0.55 {mu}g total Hg g{sup -1} f.w.) recommended by WHO. Therefore, the people living around Lago Manso should be informed of the health effects of Hg, and fish consumption recommendations should be carried out. The accumulation of Hg varies widely between species as shown by the bioaccumulation factor which ranges between 5.08 and 5.59 log units. The observed variation is explained by differences in diet and trophic position with piscivorous fish exhibiting the highest mean Hg concentration, followed by carnivorous and omnivorous species. Carbon isotope analyses imply that trophic position is not the only cause of the observed differences in Hg levels between

  13. Mineralogical and Geochemical Characteristics of Late Permian Coals from the Mahe Mine, Zhaotong Coalfield, Northeastern Yunnan, China

    Directory of Open Access Journals (Sweden)

    Xibo Wang

    2015-07-01

    Full Text Available This paper reports the mineralogical and geochemical compositions of the Late Permian C2, C5a, C5b, C6a, and C6b semianthracite coals from the Mahe mine, northeastern Yunnan, China. Minerals in the coals are mainly made up of quartz, chamosite, kaolinite, mixed-layer illite/smectite (I/S, pyrite, and calcite; followed by anatase, dolomite, siderite, illite and marcasite. Similar to the Late Permian coals from eastern Yunnan, the authigenic quartz and chamosite were precipitated from the weathering solution of Emeishan basalt, while kaolinite and mixed-layer I/S occurring as lenses or thin beds were related to the weathering residual detrital of Emeishan basalt. However, the euhedral quartz and apatite particles in the Mahe coals were attributed to silicic-rock detrital input. It further indicates that there has been silicic igneous eruption in the northeastern Yunnan. Due to the silicic rock detrital input, the Eu/Eu* value of the Mahe coals is lower than that of the Late Permian coals from eastern Yunnan, where the detrital particles were mainly derived from the basalt. The high contents of Sc, V, Cr, Co, Ni, Cu, Ga, and Sn in the Mahe coals were mainly derived from the Kangdian Upland.

  14. Reservoir management

    International Nuclear Information System (INIS)

    Satter, A.; Varnon, J.E.; Hoang, M.T.

    1992-01-01

    A reservoir's life begins with exploration leading to discovery followed by delineation of the reservoir, development of the field, production by primary, secondary and tertiary means, and finally to abandonment. Sound reservoir management is the key to maximizing economic operation of the reservoir throughout its entire life. Technological advances and rapidly increasing computer power are providing tools to better manage reservoirs and are increasing the gap between good and neural reservoir management. The modern reservoir management process involves goal setting, planning, implementing, monitoring, evaluating, and revising plans. Setting a reservoir management strategy requires knowledge of the reservoir, availability of technology, and knowledge of the business, political, and environmental climate. Formulating a comprehensive management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, facilities requirements, economic optimization, and management approval. This paper provides management, engineers, geologists, geophysicists, and field operations staff with a better understanding of the practical approach to reservoir management using a multidisciplinary, integrated team approach

  15. Reservoir management

    International Nuclear Information System (INIS)

    Satter, A.; Varnon, J.E.; Hoang, M.T.

    1992-01-01

    A reservoir's life begins with exploration leading to discovery followed by delineation of the reservoir, development of the field, production by primary, secondary and tertiary means, and finally to abandonment. Sound reservoir management is the key to maximizing economic operation of the reservoir throughout its entire life. Technological advances and rapidly increasing computer power are providing tools to better manage reservoirs and are increasing the gap between good and neutral reservoir management. The modern reservoir management process involves goal setting, planning, implementing, monitoring, evaluating, and revising plans. Setting a reservoir management strategy requires knowledge of the reservoir, availability of technology, and knowledge of the business, political, and environmental climate. Formulating a comprehensive management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, facilities requirements, economic optimization, and management approval. This paper provides management, engineers geologists, geophysicists, and field operations staff with a better understanding of the practical approach to reservoir management using a multidisciplinary, integrated team approach

  16. Effects of fractal pore on coal devolatilization

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yongli; He, Rong [Tsinghua Univ., Beijing (China). Dept. of Thermal Engineering; Wang, Xiaoliang; Cao, Liyong [Dongfang Electric Corporation, Chengdu (China). Centre New Energy Inst.

    2013-07-01

    Coal devolatilization is numerically investigated by drop tube furnace and a coal pyrolysis model (Fragmentation and Diffusion Model). The fractal characteristics of coal and char pores are investigated. Gas diffusion and secondary reactions in fractal pores are considered in the numerical simulations of coal devolatilization, and the results show that the fractal dimension is increased firstly and then decreased later with increased coal conversions during devolatilization. The mechanisms of effects of fractal pores on coal devolatilization are analyzed.

  17. Application of mine water leaching protocol on coal fly ash to assess leaching characteristics for suitability as a mine backfill material.

    Science.gov (United States)

    Madzivire, Godfrey; Ramasenya, Koena; Tlowana, Supi; Coetzee, Henk; Vadapalli, Viswanath R K

    2018-04-16

    Over the years, coal mining in the Mpumalanga Province of South Africa has negatively affected the environment by causing pollution of water resources, land subsidence and spontaneous coal combustion. Previous studies show that in-situ treatment of acid mine drainage (AMD) using coal fly ash (CFA) from local power stations was possible and sludge recovered out of such treatment can be used to backfill mines. In this article, the authors have attempted to understand the leaching characteristics of CFA when placed underground as a backfill material using the mine water leaching protocol (MWLP). The results show that the migration of contaminants between the coal fly ash and the AMD in the mine voids depends on the pH and quality of the mine water. While backfilling mine voids with CFA can neutralize and scavenge between 50% and 95% of certain environmentally sensitive elements from AMD such as Fe, Al, Zn, Cu, Ni, Co and Mn. At this moment, it is also important to point out that certain scavenged/removed contaminants from the AMD during initial phases of backfilling can be remobilized by the influx of acidic water into the mine voids. It has therefore been concluded that, while CFA can be used to backfill mine voids, the influx of fresh acidic mine water should be avoided to minimize the remobilization of trapped contaminants such as Fe, Al, Mn and As. However, the pozzolanic material resulting from the CFA-AMD interaction could prevent such influx.

  18. Relationship of HIV Reservoir Characteristics with Immune Status and Viral Rebound Kinetics in an HIV Therapeutic Vaccine Study

    Science.gov (United States)

    Li, Jonathan Z.; Heisey, Andrea; Ahmed, Hayat; Wang, Hongying; Zheng, Lu; Carrington, Mary; Wrin, Terri; Schooley, Robert T.; Lederman, Michael M.; Kuritzkes, Daniel R.

    2014-01-01

    Objectives To evaluate the impact of therapeutic HIV vaccination on the HIV reservoir, and assess the relationship of the viral reservoir with HIV-specific immune status and viral rebound kinetics. Design Retrospective analysis of ACTG A5197, a randomized, placebo-controlled trial of a therapeutic rAd5 HIV-1 gag vaccine. Methods Participants received vaccine/placebo at weeks 0, 4, and 26 prior to a 16-week analytic treatment interruption (ATI) at week 38. Cell-associated HIV-1 RNA and DNA (CA-RNA and CA-DNA) and HIV-1 residual viremia (RV) were quantified at weeks 0, 8, and 38. HIV-specific CD4+/CD8+ activity were assessed by an intracellular cytokine staining assay. Results At study entry, CA-RNA and CA-DNA levels were correlated inversely with the numbers of HIV-specific CD4+ interferon-γ-producing cells (CA-RNA: r = −0.23, P=0.03 and CA-DNA: r = −0.28, P<0.01, N=93). Therapeutic HIV vaccination induced HIV-specific CD4+ activity, but did not significantly affect levels of CA-RNA or CA-DNA. Vaccine recipients with undetectable RV at week 8 had higher frequencies of HIV-specific CD4+ and CD8+ interferon-γ-producing cells (undetectable versus detectable RV: 277 versus 161 CD4+ cells/106 lymphocytes, P=0.03 and 1326 versus 669 CD8+ cells/106 lymphocytes, P=0.04). Pre-ATI CA-RNA and CA-DNA were associated with post-ATI plasma HIV set point (CA-RNA: r = 0.51, P<0.01 and CA-DNA: r = 0.47, P<0.01). Conclusions Vaccine-induced T-cell responses were associated with a modest transient effect on RV, but more potent immune responses and/or combination treatment with latency-reversing agents are needed to reduce the HIV reservoir. HIV reservoir measures may act as biomarkers of post-ATI viral rebound kinetics. PMID:25254301

  19. A Poromechanical Model for Coal Seams Injected with Carbon Dioxide: From an Isotherm of Adsorption to a Swelling of the Reservoir Un modéle poromécanique pour l’injection de dioxyde de carbone dans des veines de charbon : d’une isotherme d’adsorption à un gonflement du réservoir

    Directory of Open Access Journals (Sweden)

    Nikoosokhan S.

    2012-11-01

    Full Text Available Injecting carbon dioxide into deep unminable coal seams can enhance the amount of methane recovered from the seam. This process is known as CO2-Enhanced Coal Bed Methane production (CO2-ECBM. The seam is a porous medium whose porous system is made of cleats (small natural fractures and of coal pores (whose radius can be as small as a few angström. During the injection process, the molecules of CO2 get adsorbed in the coal pores. Such an adsorption makes the coal swell, which, in the confined conditions that prevail underground, induces a closure of the cleat system of the coal bed reservoir and a loss of injectivity. In this work, we develop a poromechanical model which, starting from the knowledge of an adsorption isotherm and combined with reservoir simulations, enables to estimate the variations of injectivity of the coal bed reservoir over time during the process of injection. The model for the coal bed reservoir is based on poromechanical equations that explicitly take into account the effect of adsorption on the mechanical behavior of a microporous medium. We consider the coal bed reservoir as a dual porosity (cleats and coal porosity medium, for which we derive a set of linear constitutive equations. The model requires as an input the adsorption isotherm on coal of the fluid considered. Reversely, the model provides a way to upscale an adsorption isotherm into a meaningful swelling of the coal bed reservoir at the macroscopic scale. The parameters of the model are calibrated on data on coal samples available in the literature. Reservoir simulations of an injection of carbon dioxide in a coal seam are performed with an in-house finite volume and element code. The variations of injection rate over time during the process of injection are obtained from the simulations. The effect of the compressibility of the coal matrix on those variations is discussed. L’injection de dioxyde de carbone dans des veines de charbon profondes peut augmenter

  20. Burning characteristics and gaseous/solid emissions of blends of pulverized coal with waste tire-derived fuel

    Energy Technology Data Exchange (ETDEWEB)

    Levendis, Y.A.; Atal, A.; Courtemanche, B.; Carlson, J.B. [Northeastern University, Boston, MA (United States). Dept. of Mechanical, Industrial and Manufacturing Engineering

    1998-10-01

    The combustion behaviour and the emissions from blends of a pulverized bituminous coal and ground waste automobile tires were investigated. Combustion took place under steady flow conditions, in an electrically-heated drop-tube furnace in air at a gas temperature of 1150{degree}C and a particle heating rate of approximate to 10{sup 5}{degree}C/s. Combustion observations were conducted with simultaneous pyrometry and cinematography. Interparticle flame interactions were visually observed in the near-stoichiometric and fuel-rich regions. Volatile flame interactions were apparent at a lower phi for tire crumb particles than for coal particles and became progressively more intense with increasing phi until at sufficiently high phi`s large group flames formed for tire particles. As particle flame interactions increased, average maximum temperatures in the flame decreased. Coal particles resisted the formation of group flames, even at high phi`s. Such observations correlated with the trends observed for the PAH emissions of the two fuels, those of tire crumb being much higher than those of coal Some stratification in the combustion of blends of particles of the two fuels was observed. This kept the PAH emissions lower levels than expected. NO{sub x} emissions from tires were much lower than those of coal, while those of the blends were close to the weighted average emissions. SO{sub 2} emissions from the blends were close to the weighted average emissions of the two fuels. Blending coal with tire reduced the CO{sub 2} emissions of coal but increased the CO emissions. Particulate emissions (soot and ash), measured in the range of 0.4 to 8{mu}m, increased with phi. Generally, tire produced more mass of submicron particulates than coal. Particulate emissions of blends of the two fuels were close to those expected based on weighted average of the two fuels.

  1. Measurements of Gasification Characteristics of Coal and Char in CO2-Rich Gas Flow by TG-DTA

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2013-01-01

    Full Text Available Pyrolysis, combustion, and gasification properties of pulverized coal and char in CO2-rich gas flow were investigated by using gravimetric-differential thermal analysis (TG-DTA with changing O2%, heating temperature gradient, and flow rate of CO2-rich gases provided. Together with TG-DTA, flue gas generated from the heated coal, such as CO, CO2, and hydrocarbons (HCs, was analyzed simultaneously on the heating process. The optimum O2% in CO2-rich gas for combustion and gasification of coal or char was discussed by analyzing flue gas with changing O2 from 0 to 5%. The experimental results indicate that O2% has an especially large effect on carbon oxidation at temperature less than 1100°C, and lower O2 concentration promotes gasification reaction by producing CO gas over 1100°C in temperature. The TG-DTA results with gas analyses have presented basic reference data that show the effects of O2 concentration and heating rate on coal physical and chemical behaviors for the expected technologies on coal gasification in CO2-rich gas and oxygen combustion and underground coal gasification.

  2. Coal type and burnout performance

    Energy Technology Data Exchange (ETDEWEB)

    Lester, E.; Cloke, M. [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering

    1999-07-01

    A variety of coals underwent refire tests in a drop tube furnace. Characteristics of the coal fractions, the pyrolysed char fractions and the refired char fractions were compared to determine links between coal composition, intermediate char products and burnout. 9 refs., 1 fig., 2 tabs.

  3. Leaching characteristics of toxic constituents from coal fly ash mixed soils under the influence of pH

    Energy Technology Data Exchange (ETDEWEB)

    Komonweeraket, Kanokwan [Department of Civil and Environmental Engineering, University of Wisconsin, Madison, WI 53706 (United States); Cetin, Bora, E-mail: bora.cetin@sdsmt.edu [College of Engineering, University of Georgia, Athens, GA 30602 (United States); Benson, Craig H., E-mail: chbenson@wisc.edu [Department of Civil and Environmental Engineering, University of Wisconsin, Madison, WI 53706 (United States); Aydilek, Ahmet H., E-mail: aydilek@umd.edu [Department of Civil and Environmental Engineering, University of Maryland, College Park, MD 20742 (United States); Edil, Tuncer B., E-mail: edil@engr.wisc.edu [Department of Civil and Environmental Engineering, University of Wisconsin, Madison, WI 53706 (United States)

    2015-04-15

    Highlights: • The impact of pH on the leaching of elements and metals from fly ash mixed soils. • Generally Ca, Cd, Mg, and Sr follows a cationic leaching pattern. • The leaching of As and Se shows an oxyanionic leaching pattern. • The leaching behavior of elements does not change based on material type. • Different fly ash types show different abilities in immobilizing trace elements. - Abstract: Leaching behaviors of Arsenic (As), Barium (Ba), Calcium (Ca), Cadmium (Cd), Magnesium (Mg), Selenium (Se), and Strontium (Sr) from soil alone, coal fly ash alone, and soil-coal fly ash mixtures, were studied at a pH range of 2–14 via pH-dependent leaching tests. Seven different types of soils and coal fly ashes were tested. Results of this study indicated that Ca, Cd, Mg, and Sr showed cationic leaching pattern while As and Se generally follows an oxyanionic leaching pattern. On the other hand, leaching of Ba presented amphoteric-like leaching pattern but less pH-dependent. In spite of different types and composition of soil and coal fly ash investigated, the study reveals the similarity in leaching behavior as a function of pH for a given element from soil, coal fly ash, and soil-coal fly ash mixtures. The similarity is most likely due to similar controlling mechanisms (e.g., solubility, sorption, and solid-solution formation) and similar controlling factors (e.g., leachate pH and redox conditions). This offers the opportunity to transfer knowledge of coal fly ash that has been extensively characterized and studied to soil stabilized with coal fly ash. It is speculated that unburned carbon in off-specification coal fly ashes may provide sorption sites for Cd resulting in a reduction in concentration of these elements in leachate from soil-coal fly ash mixture. Class C fly ash provides sufficient CaO to initiate the pozzolanic reaction yielding hydrated cement products that oxyanions, including As and Se, can be incorporated into.

  4. Assessment of rock mass characteristics and the excavation disturbed zone in the Lingxin Coal Mine beneath the Xitian river, China

    International Nuclear Information System (INIS)

    Xingping Lai

    2006-01-01

    Safe production and induced hazard prevention in coal mines mainly concern problems in the excavation disturbed zone (EDZ), but coal mining can also make a significant impact on the environment. Comprehensive techniques using a borehole TV viewer system, electrical logging, and monitoring of drilling fluid leakage offer the ability to identify changing geological conditions and the location of any nearby abandoned mining workings. The inner collapsed zone and the expanding height of the crack zone transmitting water plus their spatial distribution after excavating the superincumbent coal seam stratum are determined at no. L3414 workings, Lingxin Coal Mine beneath the Xitian river, China. An integrated system of GIS-based on a stochastic model, which has been developed for the prediction of dynamic subsidence coupling the time function and probabilistic integral method, is verified through practice at the Lingxin Coal Mine. This development has greatly expanded the ability of the mine operator to characterize previously inaccessible areas of the mine, providing a reliable basis for safe mining and prevention of induced-hazards to ensure high production mining underneath the river bed. (author)

  5. Arsenic concentrations in Chinese coals

    International Nuclear Information System (INIS)

    Wang Mingshi; Zheng Baoshan; Wang Binbin; Li Shehong; Wu Daishe; Hu Jun

    2006-01-01

    The arsenic concentrations in 297 coal samples were collected from the main coal-mines of 26 provinces in China were determined by molybdenum blue coloration method. These samples were collected from coals that vary widely in coal rank and coal-forming periods from the five main coal-bearing regions in China. Arsenic content in Chinese coals range between 0.24 to 71 mg/kg. The mean of the concentration of Arsenic is 6.4 ± 0.5 mg/kg and the geometric mean is 4.0 ± 8.5 mg/kg. The level of arsenic in China is higher in northeastern and southern provinces, but lower in northwestern provinces. The relationship between arsenic content and coal-forming period, coal rank is studied. It was observed that the arsenic contents decreases with coal rank in the order: Tertiary > Early Jurassic > Late Triassic > Late Jurassic > Middle Jurassic > Late Permian > Early Carboniferous > Middle Carboniferous > Late Carboniferous > Early Permian; It was also noted that the arsenic contents decrease in the order: Subbituminous > Anthracite > Bituminous. However, compared with the geological characteristics of coal forming region, coal rank and coal-forming period have little effect on the concentration of arsenic in Chinese coal. The average arsenic concentration of Chinese coal is lower than that of the whole world. The health problems in China derived from in coal (arsenism) are due largely to poor local life-style practices in cooking and home heating with coal rather than to high arsenic contents in the coal

  6. Integrating gravimetric and interferometric synthetic aperture radar data for enhancing reservoir history matching of carbonate gas and volatile oil reservoirs

    KAUST Repository

    Katterbauer, Klemens; Arango, Santiago; Sun, Shuyu; Hoteit, Ibrahim

    2016-01-01

    Reservoir history matching is assuming a critical role in understanding reservoir characteristics, tracking water fronts, and forecasting production. While production data have been incorporated for matching reservoir production levels

  7. Report on results of research. Basic studies on characteristics of coal char gasification under pressure; Sekitan char no kaatsuka ni okeru gas ka tokuseino kiso kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This paper explains basic studies on characteristics of coal char gasification under pressure. Hydro-gasification of coal needs as a gasifying agent a large amount of hydrogen, which is effectively produced by the water gasification of exhaust unreacted residual char. In fiscal 1975, gasification was tested on Taiheiyo coal carbonized char by an atmospheric fluidized gasifier of 28 mm bore. In fiscal 1976, experiment was conducted under pressure by fully improving the auxiliary safety equipment. The char and gas yield increased with higher pressure in pressurized carbonization by an autoclave. In fiscal 1977, clinker was successfully prevented by using quartz sand for a fluidized medium. In fiscal 1978, two-stage continuous gasification was examined. In fiscal 1979, correlation was determined between operation factors such as gasification pressure, temperature, etc., and clinker formation/char reactivity. An experiment was conducted for particle pop-out using a pressurized fluidized bed of 100 mm inner diameter, with the pop-out quantity found to be proportional to the 0.38th power of a pressure. A high pressure fluidized gasifier was built having a char processing capacity of 1 t/day, 20 atmospheric pressure, and an inner diameter of 100 mm. In fiscal 1980, this device was continuously operated, elucidating problems for the practicability. (NEDO)

  8. Structural and functional characteristics of natural and constructed channels draining a reclaimed mountaintop removal and valley fill coal mine

    Science.gov (United States)

    Mountaintop removal and valley fill (MTR/VF) coal mining has altered the landscape of the Central Appalachian region in the United States. The goals of this study were to 1) compare the structure and function of natural and constructed stream channels in forested and MTR/VF catch...

  9. New coal

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

    Specially dedicated to coal, this edition comprises a series of articles of general interest dealing with the position of the French coalmining industry (interview with M.P. Gardent), the coal market in France, the work of CERCHAR, etc. New techniques, in-situ gasification of deep coal, gasification of coal by nuclear methods, the conversion of coal into petrol, the Emile Huchet power plant of Houilleres du Bassin de Lorraine, etc., are dealt with.

  10. Coal upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, S. [IEA Clean Coal Centre, London (United Kingdom)

    2009-10-15

    This report examines current technologies and those likely to be used to produce cleaner coal and coal products, principally for use in power generation and metallurgical applications. Consideration is also given to coal production in the leading coal producing countries, both with developed and developing industries. A range of technologies are considered. These include the coal-based liquid fuel called coal water mixture (CWM) that may compete with diesel, the production of ultra-clean coal (UCC) and coal liquefaction which competes with oil and its products. Technologies for upgrading coal are considered, especially for low rank coals (LRC), since these have the potential to fill the gap generated by the increasing demand for coal that cannot be met by higher quality coals. Potential advantages and downsides of coal upgrading are outlined. Taking into account the environmental benefits of reduced pollution achieved through cleaner coal and reduced transport costs, as well as other positive aspects such as a predictable product leading to better boiler design, the advantages appear to be significant. The drying of low rank coals improves the energy productively released during combustion and may also be used as an adjunct or as part of other coal processing procedures. Coal washing technologies vary in different countries and the implications of this are outlined. Dry separation technologies, such as dry jigging and electrostatic separation, are also described. The demonstration of new technologies is key to their further development and demonstrations of various clean coal technologies are considered. A number of approaches to briquetting and pelletising are available and their use varies from country to country. Finally, developments in upgrading low rank coals are described in the leading coal producing countries. This is an area that is developing rapidly and in which there are significant corporate and state players. 81 refs., 32 figs., 3 tabs.

  11. Colour and toxic characteristics of metakaolinite-hematite pigment for integrally coloured concrete, prepared from iron oxide recovered from a water treatment plant of an abandoned coal mine

    Science.gov (United States)

    Sadasivam, Sivachidambaram; Thomas, Hywel Rhys

    2016-07-01

    A metakaolinite-hematite (KH) red pigment was prepared using an ocherous iron oxide sludge recovered from a water treatment plant of an abandoned coal mine. The KH pigment was prepared by heating the kaolinite and the iron oxide sludge at kaolinite's dehydroxylation temperature. Both the raw sludge and the KH specimen were characterised for their colour properties and toxic characteristics. The KH specimen could serve as a pigment for integrally coloured concrete and offers a potential use for the large volumes of the iron oxide sludge collected from mine water treatment plants.

  12. Definition of Static Voltage Characteristics of the Motor Load for the Purpose of Increase in Energy Efficiency of Coal Mines of Kuzbass

    Science.gov (United States)

    Nepsha, Fedor; Efremenko, Vladimir

    2017-11-01

    The task of determining the static load characteristics is one of the most important tasks, the solution of which is necessary for the correct development of measures to increase the energy efficiency of the Kuzbass coal mines. At present, the influence of electric receivers on the level of consumption of active and reactive power is not taken into account, therefore, the proposed measures to increase the energy efficiency are not optimal. The article analyzes the L-shaped and T-shaped circuit for the replacement of an asynchronous motor (AM), according to the results of which it is determined that the T-shaped replacement scheme is the most accurate for determination of static load characteristics. The authors proposed and implemented in the MATLAB Simulink environment an algorithm for determining the static voltage characteristics of the motor load.

  13. Coal mining in the power industry of the Federal Republic of Germany in 1993

    International Nuclear Information System (INIS)

    1994-11-01

    After an introductory text divided into the sections energy and coal market, Coal mining and brown coal mining, extensive tables containing the most important characteristic figures of German coal mining are shown. (orig.) [de

  14. Coal-92

    International Nuclear Information System (INIS)

    Hillring, B.; Sparre, C.

    1992-11-01

    Swedish consumption of coal and coke during 1991 and trends in technology, environment and market aspects of coal use are reported. Steam coal use in the heating sector was unchanged from 1991, 1.2 Mtons. Reduced consumption in smaller district heating units (due to conversion to biofuels and gas) was compensated by increased use for power generation in cogeneration plants. Coal consumption in industry fell 0.10 Mton to 0.84 Mton due to lower production in one industry branch. Import of steam coal was 1.1 Mton (down 0.5 Mton from 1990) since new rules for strategic reserves allowed a reduction of stocks. During the last five years stocks have been reduced by 2 Mtons. Import of metallurgical coal was 1.6 Mton, unchanged from 1990. The report also gives statistics for the coal using plants in Sweden, on coal R and D, and on emission laws for coal firing. (9 tabs., 2 figs.)

  15. [Pollution Assessment and Spatial Distribution Characteristics of Heavy Metals in Soils of Coal Mining Area in Longkou City].

    Science.gov (United States)

    Liu, Shuo; Wu, Quan-yuan; Cao, Xue-jiang; Wang, Ji-ning; Zhang, Long-long; Cai, Dong-quan; Zhou, Li-yuan; Liu, Na

    2016-01-15

    The present paper takes the coal mining area of Longkou City as the research area. Thirty-six topsoil (0-20 cm) samples were collected and the contents of 5 kinds of heavy metals were determined, including Cd, As, Ni, Ph, Cr. Geo-statistics analysis was used to analyze the spatial distribution of heavy metals. Principal component analysis (PCA) was used to explore the pollution sources of heavy metals and the degree of heavy metals pollution was evaluated by weighted average comprehensive pollution evaluation method. The results showed that enrichment phenomenon was significant for the 5 kinds of heavy metals. Taking secondary standard of National Environment Quality Standard for Soil as the background value, their exceed standard rates were 72.22%, 100%, 100%, 91.67%, 100%, respectively. Average contents of heavy metals in the soil samples were all over the national standard level two and were 1.53, 11.86, 2.40, 1.31, 4.09 times of the background value. In addition, the average contents were much higher than the background value of the topsoil in the eastern part of Shandong Province and were 9.85, 39.98, 8.85, 4.29, 12.71 times of the background value. According to the semivariogram model, we obtained the nugget-effects of 5 kinds of heavy metals and their values were in the order of As (0.644) > Cd (0.627) > Cr (0.538) > Ni (0.411) > Pb (0.294), all belonging to moderate spatial correlation. On the whole, the central part of the Sangyuan Coal Mine and its surrounding areas were the most seriously polluted, while the pollution of heavy metals in the east and west of the study area was relatively light. Principal component analysis suggested that the enrichment of Cd, As, Ni, Cr was due to irrigation of wastewater, the discharge of industry and enterprise, and the industrial activity. Automobile exhaust and coal combustion were the main pollution sources of Pb. The single-factor assessment of heavy metals pollution showed that the degree of different heavy metals

  16. Mercury deposition and methylmercury formation in Narraguinnep Reservoir, southwestern Colorado, USA

    Science.gov (United States)

    Gray, John E.; Hines, Mark E.; Goldstein, Harland L.; Reynolds, Richard L.

    2014-01-01

    Narraguinnep Reservoir in southwestern Colorado is one of several water bodies in Colorado with a mercury (Hg) advisory as Hg in fish tissue exceed the 0.3 μg/g guideline to protect human health recommended by the State of Colorado. Concentrations of Hg and methyl-Hg were measured in reservoir bottom sediment and pore water extracted from this sediment. Rates of Hg methylation and methyl-Hg demethylation were also measured in reservoir bottom sediment. The objective of this study was to evaluate potential sources of Hg in the region and evaluate the potential of reservoir sediment to generate methyl-Hg, a human neurotoxin and the dominant form of Hg in fish. Concentrations of Hg (ranged from 1.1 to 5.8 ng/L, n = 15) and methyl-Hg (ranged from 0.05 to 0.14 ng/L, n = 15) in pore water generally were highest at the sediment/water interface, and overall, Hg correlated with methyl-Hg in pore water (R2 = 0.60, p = 0007, n = 15). Net Hg methylation flux in the top 3 cm of reservoir bottom sediment varied from 0.08 to 0.56 ng/m2/day (mean = 0.28 ng/m2/day, n = 5), which corresponded to an overall methyl-Hg production for the entire reservoir of 0.53 g/year. No significant point sources of Hg contamination are known to this reservoir or its supply waters, although several coal-fired power plants in the region emit Hg-bearing particulates. Narraguinnep Reservoir is located about 80 km downwind from two of the largest power plants, which together emit about 950 kg-Hg/year. Magnetic minerals separated from reservoir sediment contained spherical magnetite-bearing particles characteristic of coal-fired electric power plant fly ash. The presence of fly-ash magnetite in post-1970 sediment from Narraguinnep Reservoir indicates that the likely source of Hg to the catchment basin for this reservoir has been from airborne emissions from power plants, most of which began operation in the late-1960s and early 1970s in this region.

  17. Thermal characteristics and surface morphology of char during co-pyrolysis of low-rank coal blended with microalgal biomass: Effects of Nannochloropsis and Chlorella.

    Science.gov (United States)

    Wu, Zhiqiang; Yang, Wangcai; Yang, Bolun

    2018-02-01

    In this work, the influence of Nannochloropsis and Chlorella on the thermal behavior and surface morphology of char during the co-pyrolysis process were explored. Thermogravimetric and iso-conversional methods were applied to analyzing the pyrolytic and kinetic characteristics for different mass ratios of microalgae and low-rank coal (0, 3:1, 1:1, 1:3 and 1). Fractal theory was used to quantitatively determine the effect of microalgae on the morphological texture of co-pyrolysis char. The result indicated that both the Nannochloropsis and Chlorella promoted the release of volatile from low-rank coal. Different synergistic effects on the thermal parameters and yield of volatile were observed, which could be attributed to the different compositions in the Nannochloropsis and Chlorella and operating condition. The distribution of activation energies shows nonadditive characteristics. Fractal dimensions of the co-pyrolysis char were higher than the individual char, indicating the promotion of disordered degree due to the addition of microalgae. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Coal 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    ACR's Coal 1992, the successor to the ACR Coal Marketing Manual, contains a comprehensive set of data on many aspects of the Australian coal industry for several years leading up to 1992. Tables and text give details of coal production and consumption in New South Wales, Queensland and other states. Statistics of the Australian export industry are complemented by those of South Africa, USA, New Zealand, Canada, Indonesia, China, Colombia, Poland and ex-USSR. Also listed are prices of Australian coking and non-coking coal, Australian coal stocks (and those of other major countries), loading port capacities, freight rates and coal quality requirements (analysis of coals by brand and supplier). A listing of Australian coal exporting companies is provided. A description of the spot Coal Screen Dealing System is given. World hard coal imports are listed by country and coal imports by major Asian countries tabulated. A forecast of demand by coal type and country up to the year 2000 is included.

  19. Coal pump

    Science.gov (United States)

    Bonin, John H.; Meyer, John W.; Daniel, Jr., Arnold D.

    1983-01-01

    A device for pressurizing pulverized coal and circulating a carrier gas is disclosed. This device has utility in a coal gasification process and eliminates the need for a separate collection hopper and eliminates the separate compressor.

  20. Bio-coal briquettes using low-grade coal

    Science.gov (United States)

    Estiaty, L. M.; Fatimah, D.; Widodo

    2018-02-01

    The technology in using briquettes for fuel has been widely used in many countries for both domestic and industrial purposes. Common types of briquette used are coal, peat, charcoal, and biomass. Several researches have been carried out in regards to the production and the use of briquettes. Recently, researches show that mixing coal and biomass will result in an environmentally friendly briquette with better combustion and physical characteristics. This type of briquette is known as bio-coal briquettes. Bio-coal briquettes are made from agriculture waste and coal, which are readily available, cheap and affordable. Researchers make these bio-coal briquettes with different aims and objectives, depending on the issues to address, e.g. utilizing agricultural waste as an alternative energy to replace fossil fuels that are depleting its reserves, adding coal to biomass in order to add calorific value to bio-coal briquette, and adding biomass to coal to improve its chemical and physical properties. In our research, biocoal briquettes are made to utilize low grade coal. The biomass we use, however, is different from the ones used in past researches because it has undergone fermentation. The benefits of using such biomass are 1. Fermentation turns the hemi cellulose into a simpler form, so that the burning activation energy decreases while the calorific value increases. 2. Enzym produced will bind to heavy metals from coal as co-factors, forming metals that are environmentally friendly.

  1. A sequential approach to control gas for the extraction of multi-gassy coal seams from traditional gas well drainage to mining-induced stress relief

    International Nuclear Information System (INIS)

    Kong, Shengli; Cheng, Yuanping; Ren, Ting; Liu, Hongyong

    2014-01-01

    Highlights: • The gas reservoirs characteristics are measured and analyzed. • A sequential approach to control gas of multi-gassy coal seams is proposed. • The design of gas drainage wells has been improved. • The utilization ways of different concentrations of gas production are shown. - Abstract: As coal resources become exhausted in shallow mines, mining operations will inevitably progress from shallow depth to deep and gassy seams due to increased demands for more coal products. However, during the extraction process of deeper and gassier coal seams, new challenges to current gas control methods have emerged, these include the conflict between the coal mine safety and the economic benefits, the difficulties in reservoirs improvement, as well as the imbalance between pre-gas drainage, roadway development and coal mining. To solve these problems, a sequential approach is introduced in this paper. Three fundamental principles are proposed: the mining-induced stress relief effect of the first-mined coalbed should be sufficient to improve the permeability of the others; the coal resource of the first-mined seams must be abundant to guarantee the economic benefits; the arrangement of the vertical wells must fit the underground mining panel. Tunlan coal mine is taken as a typical example to demonstrate the effectiveness of this approach. The approach of integrating surface coalbed methane (CBM) exploitation with underground gas control technologies brings three major benefits: the improvement of underground coal mining safety, the implementation of CBM extraction, and the reduction of greenhouse gas emissions. This practice could be used as a valuable example for other coal mines having similar geological conditions

  2. Flow characteristic of Hijiori HDR reservoir from circulation test in 1991; Koon tantai Hijiori jikkenjo ni okeru senbu choryuso shiken (1991 nendo) kekka to ryudo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Shiga, T; Hyodo, M; Shinohara, N; Takasugi, S [Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan)

    1996-05-01

    This paper reports one example of flow analyses on a circulation test carried out in fiscal 1991 at the Hijiori hot dry rock experimental field (Yamagata Prefecture). A fluid circulation model was proposed to simulate an HDR circulation system for a shallow reservoir (at a depth of about 1800 m) demonstrated in the circulation test by using an electric circuit network (which expresses continuity impedance in resistance and fluid storage in capacitance). Storage capacity of the reservoir was estimated by deriving time constant of the system from data of time-based change in reservoir pressure associated with transition phenomena during the circulation test. The storage capacity was estimated separately by dividing change of storage in the reservoir by change in the reservoir pressure. To derive the storage in the reservoir, a method to calculate non-recovered flows in the circulation test was utilized. The results of evaluating the reservoir capacity in the shallow reservoir using the above two independent methods were found substantially consistent. 3 refs., 6 figs., 1 tab.

  3. Adsorption characteristics of arsenic from micro-polluted water by an innovative coal-based mesoporous activated carbon.

    Science.gov (United States)

    Li, Wei-Guang; Gong, Xu-Jin; Wang, Ke; Zhang, Xin-Ran; Fan, Wen-Biao

    2014-08-01

    An innovative coal-based mesoporous activated carbon (NCPAC) was prepared by re-agglomeration, oxidation and two-step activation using coal-blending as precursor. Adsorption capacities of As(III) and As(V) ions (<0.5mg/L) onto NCPAC as a function of pH, adsorbent dose, initial arsenic concentrations, contact time, and adsorption isotherms at 7°C was investigated. The innovative methods promoted total pore volume (1.087cm(3)/g), mesoporosity (64.31%), iodine numbers (1104mg/g), methylene blue (251.8mg/g) and ash contents (15.26%). The adsorption capacities of NCPAC for As(III) and As(V) were found to be strongly dependent on pH and contact time. The optimal pH value was 6. The equilibrium time was 60min for adsorption of As(III) and As(V) by NCPAC. The Langmuir model fitted the experimental data well for both As(III) (R(2)=0.9980) and As(V) (R(2)=0.9988). Maximum adsorption capacities of As(III) and As(V) (C0=0.50mg/L) by NCPAC were 1.491 and 1.760mg/g, respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Dependence of liquefaction behavior on coal characteristics. Part VI. Relationship of liquefaction behavior of a set of high sulfur coals to chemical structural characteristics. Final technical report, March 1981 to February 1984

    Energy Technology Data Exchange (ETDEWEB)

    Neill, P. H.; Given, P. H.

    1984-09-01

    The initial aim of this research was to use empirical mathematical relationships to formulate a better understanding of the processes involved in the liquefaction of a set of medium rank high sulfur coals. In all, just over 50 structural parameters and yields of product classes were determined. In order to gain a more complete understanding of the empirical relationships between the various properties, a number of relatively complex statistical procedures and tests were applied to the data, mostly selected from the field of multivariate analysis. These can be broken down into two groups. The first group included grouping techniques such as non-linear mapping, hierarchical and tree clustering, and linear discriminant analyses. These techniques were utilized in determining if more than one statistical population was present in the data set; it was concluded that there was not. The second group of techniques included factor analysis and stepwise multivariate linear regressions. Linear discriminant analyses were able to show that five distinct groups of coals were represented in the data set. However only seven of the properties seemed to follow this trend. The chemical property that appeared to follow the trend most closely was the aromaticity, where a series of five parallel straight lines was observed for a plot of f/sub a/ versus carbon content. The factor patterns for each of the product classes indicated that although each of the individual product classes tended to load on factors defined by specific chemical properties, the yields of the broader product classes, such as total conversion to liquids + gases and conversion to asphaltenes, tended to load largely on factors defined by rank. The variance explained and the communalities tended to be relatively low. Evidently important sources of variance have still to be found.

  5. Colour and toxic characteristics of metakaolinite–hematite pigment for integrally coloured concrete, prepared from iron oxide recovered from a water treatment plant of an abandoned coal mine

    International Nuclear Information System (INIS)

    Sadasivam, Sivachidambaram; Thomas, Hywel Rhys

    2016-01-01

    A metakaolinite-hematite (KH) red pigment was prepared using an ocherous iron oxide sludge recovered from a water treatment plant of an abandoned coal mine. The KH pigment was prepared by heating the kaolinite and the iron oxide sludge at kaolinite's dehydroxylation temperature. Both the raw sludge and the KH specimen were characterised for their colour properties and toxic characteristics. The KH specimen could serve as a pigment for integrally coloured concrete and offers a potential use for the large volumes of the iron oxide sludge collected from mine water treatment plants. - Graphical abstract: A kaolinite based red pigment was prepared using an ocherous iron oxide sludge recovered from an abandoned coal mine water treatment plant. Display Omitted - Highlights: • A red pigment was prepared by heating a kaolinite and an iron oxide sludge. • The iron oxide and the pigment were characterised for their colour properties. • The red pigment can be a potential element for integrally coloured concrete.

  6. Investigation into Mechanism of Floor Dynamic Rupture by Evolution Characteristics of Stress and Mine Tremors: A Case Study in Guojiahe Coal Mine, China

    Directory of Open Access Journals (Sweden)

    Guangjian Liu

    2018-01-01

    Full Text Available In order to explore the mechanism of floor dynamic rupture, the current study adopts a thin plate model to further investigate the condition of floor failure. One of the possible explanations could be floor buckling due to high horizontal stress and dynamic disturbance ultimately leading to rapid and massive release of elastic energy thus inducing dynamic rupture. Seismic computed tomography and 3D location were employed to explore the evolution characteristics of floor stress distribution and positions of mine tremors. In the regions of floor dynamic rupture, higher P-wave velocity was recorded prior to the dynamic rupture. On the contrary, relatively lower reading was observed after the dynamic rupture thus depicting a high stress concentration condition. Meanwhile, evolution of mine tremors revealed the accumulation and subsequent release of energy during the dynamic rupture process. It was further revealed that dynamic rupture was induced due to the superposition of static and dynamic stresses: (i the high static stress concentration due to frontal and lateral abutment stress from coal pillar and (ii dynamic stress from the fracture and caving of coal pillar, hard roof, and key stratum. In the later part of this study, the floor dynamic rupture occurrence process would be reproduced through numerical simulations within a 0.6 sec time frame. The above-mentioned findings would be used to propose a feasible mechanism for prewarning and prevention of floor dynamic rupture using seismic computed tomography and mine tremors 3D location.

  7. Flow characteristics of Hijiori HDR reservoir form circulation test in 1995; Koon tantai Hijiori jikkenjo ni okeru shinbu choryuso yobi junkan shiken (1995 nendo) kekka to ryudo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Fukushima, N; Hyodo, M; Shinohara, N; Takasugi, S [Geothermal Energy Research and Development Co. Ltd., Tokyo (Japan)

    1996-05-01

    This paper reports the result of a preliminary circulation test conducted in fiscal 1995 on a deep reservoir (at a depth of about 2200 m) in the Hijiori hot dry rock experimental field. One water injection well and two production wells were drilled to constitute a circulation loop, to which the circulation test was performed to investigate the flow characteristics thereof. The result revealed the following matters: total amount of injected water of 51500 m{sup 3} resulted in a total fluid recovery rate of about 40%; as a result of well stimulation given twice during the initial stage of the water injection, the continuity impedance in the vicinity of the injection well decreased largely (however, the continuity improvement upon the second attempt was considerably inferior to that from the first attempt); and increase in the water injection amount does not necessarily lead to increase in the production amount. The paper describes additionally that it is extremely difficult to interpret non-linearity between the injection and production amounts by using a model prepared previously with a main objective to analyze the Hijiori HDR circulation system. 1 ref., 9 figs., 1 tab.

  8. Experimental investigation of geochemical and mineralogical effects of CO2 sequestration on flow characteristics of reservoir rock in deep saline aquifers

    Science.gov (United States)

    Rathnaweera, T. D.; Ranjith, P. G.; Perera, M. S. A.

    2016-01-01

    Interactions between injected CO2, brine, and rock during CO2 sequestration in deep saline aquifers alter their natural hydro-mechanical properties, affecting the safety, and efficiency of the sequestration process. This study aims to identify such interaction-induced mineralogical changes in aquifers, and in particular their impact on the reservoir rock’s flow characteristics. Sandstone samples were first exposed for 1.5 years to a mixture of brine and super-critical CO2 (scCO2), then tested to determine their altered geochemical and mineralogical properties. Changes caused uniquely by CO2 were identified by comparison with samples exposed over a similar period to either plain brine or brine saturated with N2. The results show that long-term reaction with CO2 causes a significant pH drop in the saline pore fluid, clearly due to carbonic acid (as dissolved CO2) in the brine. Free H+ ions released into the pore fluid alter the mineralogical structure of the rock formation, through the dissolution of minerals such as calcite, siderite, barite, and quartz. Long-term CO2 injection also creates a significant CO2 drying-out effect and crystals of salt (NaCl) precipitate in the system, further changing the pore structure. Such mineralogical alterations significantly affect the saline aquifer’s permeability, with important practical consequences for the sequestration process. PMID:26785912

  9. Characterization of Coal Porosity for Naturally Tectonically Stressed Coals in Huaibei Coal Field, China

    Science.gov (United States)

    Li, Xiaoshi; Hou, Quanlin; Li, Zhuo; Wei, Mingming

    2014-01-01

    The enrichment of coalbed methane (CBM) and the outburst of gas in a coal mine are closely related to the nanopore structure of coal. The evolutionary characteristics of 12 coal nanopore structures under different natural deformational mechanisms (brittle and ductile deformation) are studied using a scanning electron microscope (SEM) and low-temperature nitrogen adsorption. The results indicate that there are mainly submicropores (2~5 nm) and supermicropores (coal and mesopores (10~100 nm) and micropores (5~10 nm) in brittle deformed coal. The cumulative pore volume (V) and surface area (S) in brittle deformed coal are smaller than those in ductile deformed coal which indicates more adsorption space for gas. The coal with the smaller pores exhibits a large surface area, and coal with the larger pores exhibits a large volume for a given pore volume. We also found that the relationship between S and V turns from a positive correlation to a negative correlation when S > 4 m2/g, with pore sizes coal. The nanopore structure (coal. PMID:25126601

  10. [Transfer characteristic and source identification of soil heavy metals from water-level-fluctuating zone along Xiangxi River, three-Gorges Reservoir area].

    Science.gov (United States)

    Xu, Tao; Wang, Fei; Guo, Qiang; Nie, Xiao-Qian; Huang, Ying-Ping; Chen, Jun

    2014-04-01

    Transfer characteristics of heavy metals and their evaluation of potential risk were studied based on determining concentration of heavy metal in soils from water-level-fluctuating zone (altitude:145-175 m) and bank (altitude: 175-185 m) along Xiangxi River, Three Gorges Reservoir area. Factor analysis-multiple linear regression (FA-MLR) was employed for heavy metal source identification and source apportionment. Results demonstrate that, during exposing season, the concentration of soil heavy metals in water-level-fluctuation zone and bank showed the variation, and the concentration of soil heavy metals reduced in shallow soil, but increased in deep soil at water-level-fluctuation zone. However, the concentration of soil heavy metals reduced in both shallow and deep soil at bank during the same period. According to the geoaccumulation index,the pollution extent of heavy metals followed the order: Cd > Pb > Cu > Cr, Cd is the primary pollutant. FA and FA-MLR reveal that in soils from water-level-fluctuation zone, 75.60% of Pb originates from traffic, 62.03% of Cd is from agriculture, 64.71% of Cu and 75.36% of Cr are from natural rock. In soils from bank, 82.26% of Pb originates from traffic, 68.63% of Cd is from agriculture, 65.72% of Cu and 69.33% of Cr are from natural rock. In conclusion, FA-MLR can successfully identify source of heavy metal and compute source apportionment of heavy metals, meanwhile the transfer characteristic is revealed. All these information can be a reference for heavy metal pollution control.

  11. Correlation between the coal quality from 'Suvodol' and briquetting processes for coals, peat and other combustible materials (coal deposit in Macedonia)

    International Nuclear Information System (INIS)

    Damjanovski, Dragan; Popovski, Dushko; Mitrevski, Pece

    1997-01-01

    In this paper the regression equations for the characteristics of Suvodol coal and the technological parameters of obtained briquets are given. It is shown that correlations between the coal characteristics are linear, while correlations between briquetting parameters are nonlinear

  12. Reconnaissance coal study in the Susitna basin, 2014

    Science.gov (United States)

    David L. LePain,; Stanley, Richard G.; Harun, Nina T.; Helmold, Kenneth T.; Tsigonis, Rebekah

    2015-01-01

    The Alaska Division of Geological & Geophysical Surveys (DGGS) conducted fieldwork during the summer of 2014 in the Susitna basin as part of an ongoing evaluation of the hydrocarbon potential of frontier basins, particularly those near the Railbelt region (for example, Decker and others, 2013; Gillis and others, 2013). Topical studies associated with this recent work include sedimentary facies analysis (LePain and others, 2015) and structural geology investigations (Gillis and others, 2015). The Susitna basin contains coal-bearing Paleogene and Neogene strata correlative with formations that host oil and gas in Cook Inlet basin to its south. Isotopic signatures of natural gas reservoired in the Miocene/Pliocene Sterling and Miocene Beluga Formations suggest a biogenic origin for Cook Inlet gas (Claypool and others, 1980). To assess the biogenic gas potential of the Susitna basin, it is important to obtain information from its coal-bearing units.Characteristics of coal, such as maturity/rank and cleat development are key parameters influencing viability of a biogenic gas system (Laubach and others, 1998). In an early study of the Susitna basin (Beluga–Yentna region), Barnes (1966) identified, analyzed, and recognized potentially valuable subbituminous coal resources at Fairview Mountain, Canyon Creek, and Johnson Creek. Merritt (1990), in a sedimentological study to evaluate surface coal mining potential of the Tertiary rocks of the Susitna basin (Susitna lowland), concluded that the basin contained several billion tons of mineable reserves. This preliminary report offers a brief summary of new information on coals in the Susitna Basin acquired during associated stratigraphic studies (see LePain and others, 2015). 

  13. Combustion characteristics and retention-emission of selenium during co-firing of torrefied biomass and its blends with high ash coal.

    Science.gov (United States)

    Ullah, Habib; Liu, Guijian; Yousaf, Balal; Ali, Muhammad Ubaid; Abbas, Qumber; Zhou, Chuncai

    2017-12-01

    The combustion characteristics, kinetic analysis and selenium retention-emission behavior during co-combustion of high ash coal (HAC) with pine wood (PW) biomass and torrefied pine wood (TPW) were investigated through a combination of thermogravimetric analysis (TGA) and laboratory-based circulating fluidized bed combustion experiment. Improved ignition behavior and thermal reactivity of HAC were observed through the addition of a suitable proportion of biomass and torrefied. During combustion of blends, higher values of relative enrichment factors in fly ash revealed the maximum content of condensing volatile selenium on fly ash particles, and depleted level in bottom ash. Selenium emission in blends decreased by the increasing ratio of both PW and TPW. Higher reductions in the total Se volatilization were found for HAC/TPW than individual HAC sample, recommending that TPW have the best potential of selenium retention. The interaction amongst selenium and fly ash particles may cause the retention of selenium. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. The production of high load coal-water mixtures on the base of Kansk-Achinsk Coal Basin

    Energy Technology Data Exchange (ETDEWEB)

    Demidov, Y.; Bruer, G.; Kolesnikova, S. [Research and Design Institute for Problems of Development of Kansk-Achinsk Coal Basin (KATEKNilugol), Krasnoyarsk (Russian Federation)

    1995-12-01

    The results of the {open_quotes}KATEKNIIugol{close_quotes} work on the problems of high load coal-water mixtures are given in this article. General principles of the mixture production, short characteristics of Kansk-Achinsk coals, the experimental results of the coal mixture production on a test-industrial scale, the suspension preparation on the base of coal mixtures, technical-economical indexes of tested coal pipeline variants based on Kansk-Achinsk coals are described.

  15. Ten questions on the future of coal

    International Nuclear Information System (INIS)

    Ruelle, G.

    2005-01-01

    The author comments data and information on the main uses of coal, the evolution of the coal share in the world energy consumption, the amounts and locations of coal reserves in comparison with oil and gas, the coal reserves left in the European Union, the world coal market characteristics with respect to those of oil and gas, the reason of the bad environmental reputation of coal, the internal cost of a KWh produced by a coal power station, the external cost resulting from its environmental pollution, the possibility of reducing those defects by 2020, 2040, 2060, the way of transforming coal into oil and to which cost, in order to expand its use to modern transports, the role of coal during the 21. century and the possibilities of CO 2 sequestration

  16. Australian coal

    Energy Technology Data Exchange (ETDEWEB)

    1985-11-01

    Total export shipments of coal in Australia in the year ending June 30 1985 reached a record of 83.8 Mt. The export trade is expected to bring in an income of 4 billion Australian dollars in the current year making coal Australia's biggest revenue-earning export commodity. This article presents a brief overview of the Australian coal industry with production and export statistics and information on major open pit and underground mines.

  17. Computer-aided planning of brown coal seam mining in regard to coal quality

    Energy Technology Data Exchange (ETDEWEB)

    Ciesielski, R.; Lehmann, A.; Rabe, H.; Richter, S.

    1988-09-01

    Discusses features of the geologic SORVER software developed at the Freiberg Fuel Institute, GDR. The program processes geologic data from exploratory wells, petrographic characteristics of a coal seam model, technological mining parameters and coal quality requirements of consumers. Brown coal reserves of coking coal, gasification coal, briquetting coal and steam coal are calculated. Vertical seam profiles and maps of seam horizon isolines can be plotted using the program. Coal quality reserves along the surface of mine benches, mining block widths and lengths for excavators, maximum possible production of individual coal qualities by selective mining, and coal quality losses due to mining procedures are determined. The program is regarded as a means of utilizing deposit reserves more efficiently. 5 refs.

  18. Coal - 96

    International Nuclear Information System (INIS)

    Sparre, C.

    1996-09-01

    The report deals mainly with coal consumption, but also gives some information about technology, environmental aspects and markets. Data have been collected by questionnaires or via telephone. The use of steam coal for heating was 0.8 Mtons (down 20% from 1994). Cogeneration plants were the main users. Taxes and environmental reasons cause a reduction of the coal use that will probably continue the next years. Use of steam coal in industry has been constant at a level of 0.7 Mtons. The import of metallurgical coal rests constant at a level of 1.6 Mtons. 1.2 Mtons of coke was produced, and 0.3 Mtons imported. The PFBC-plant at Vaertan, Stockholm used 0.13 Mtons of coal, while some coal fired power plants have been converted to peat and wood fuels. The average price of steam coal imported to Sweden in 1995 was 333 SEK/ton, 6% higher than in 1994. The contract prices for delivery 1996 are about the same as at the end of 1995. All cogeneration plants have some sort of SO 2 removal system, mostly wet-dry. The largest plant, at Vaesteraas, has recently invested in a SCR system for NO x removal. Most other plants are using low NO x burners or SNCR systems, based on ammonia or urea, which reduce the emissions 50 - 70%. Some statistic about the world coal market is also given in the report

  19. Venezuelan coal

    International Nuclear Information System (INIS)

    Vazquez, L.U.

    1991-01-01

    The existence of coal deposits in Venezuela has been known since the early nineteenth century, when the Naricual Mines were discovered in the State of Anzoategui Eastern Venezuela. Through the years the Venezuelan coal business had its ups and downs, but it was not until 1988 that we could properly say that our coal began to play a role in the international market. This paper reports that it is only now, in the nineties, that Venezuelan coal projects have come under a planning, promotional and developmental policy preparing the ground for the great projects Venezuela will have in the not-too-distant future

  20. [Characteristics of dissolved organic carbon release under inundation from typical grass plants in the water-level fluctuation zone of the Three Gorges Reservoir area].

    Science.gov (United States)

    Tan, Qiu-Xia; Zhu, Boi; Hua, Ke-Ke

    2013-08-01

    The water-level fluctuation zone of the Three Gorges Reservoir (TGR) exposes in spring and summer, then, green plants especially herbaceous plants grow vigorously. In the late of September, water-level fluctuation zone of TGR goes to inundation. Meanwhile, annually accumulated biomass of plant will be submerged for decaying, resulting in organism decomposition and release a large amount of dissolved organic carbon (DOC). This may lead to negative impacts on water environment of TGR. The typical herbaceous plants from water-level fluctuation zone were collected and inundated in the laboratory for dynamic measurements of DOC concentration of overlying water. According to the determination, the DOC release rates and fluxes have been calculated. Results showed that the release process of DOC variation fitted in a parabolic curve. The peak DOC concentrations emerge averagely in the 15th day of inundation, indicating that DOC released quickly with organism decay of herbaceous plant. The release process of DOC could be described by the logarithm equation. There are significant differences between the concentration of DOC (the maximum DOC concentration is 486.88 mg x L(-1) +/- 35.97 mg x L(-1) for Centaurea picris, the minimum is 4.18 mg x L(-1) +/- 1.07 mg x L(-1) for Echinochloacrus galli) and the release amount of DOC (the maximum is 50.54 mg x g(-1) for Centaurea picris, the minimum is 6.51 mg x g(-1) for Polygonum hydropiper) due to different characteristics of plants, especially, the values of C/N of herbaceous plants. The cumulative DOC release quantities during the whole inundation period were significantly correlated with plants' C/N values in linear equations.

  1. Sedimentology and Reservoir Characteristics of Early Cretaceous Fluvio-Deltaic and Lacustrine Deposits, Upper Abu Gabra Formation, Sufyan Sub-basin, Muglad Rift Basin, Sudan

    Science.gov (United States)

    Yassin, Mohamed; Abdullatif, Osman; Hariri, Mustafa

    2017-04-01

    Sufyan Sub-basin is an East-West trending Sub-basin located in the northwestern part of the Muglad Basin (Sudan), in the eastern extension of the West and Central Africa Rift System (WCARS). The Early Cretaceous Abu Gabra Formation considered as the main source rock in the Muglad Basin. In Sufyan Sub-basin the Early Cretaceous Upper Abu Gabra Formation is the main oil-producing reservoir. It is dominated by sandstone and shales deposited in fluvio-deltaic and lacustrine environment during the first rift cycle in the basin. Depositional and post-depositional processes highly influenced the reservoir quality and architecture. This study investigates different scales of reservoir heterogeneities from macro to micro scale. Subsurface facies analysis was analyzed based on the description of six conventional cores from two wells. Approaches include well log analysis, thin sections and scanning electron microscope (SEM) investigations, grain-size, and X-ray diffraction (XRD) analysis of the Abu Gabra sandstone. The cores and well logs analyses revealed six lithofacies representing fluvio-deltaic and lacustrine depositional environment. The sandstone is medium to coarse-grained, poorly to moderately sorted and sub-angular to subrounded, Sub-feldspathic arenite to quartz arenite. On macro-scale, reservoir quality varies within Abu Gabra reservoir where it shows progressive coarsening upward tendencies with different degrees of connectivity. The upper part of the reservoir showed well connected and amalgamated sandstone bodies, the middle to lower parts, however, have moderate to low sandstone bodies' connectivity and amalgamation. On micro-scale, sandstone reservoir quality is directly affected by textures and diagenesis.The XRD and SEM analyses show that kaolinite and chlorite clay are the common clay minerals in the studied samples. Clay matrix and quartz overgrowth have significantly reduced the reservoir porosity and permeability, while the dissolution of feldspars

  2. A spatial analysis of China's coal flow

    International Nuclear Information System (INIS)

    Mou Dunguo; Li Zhi

    2012-01-01

    The characteristics of China's energy structure and the distribution of its coal resources make coal transportation a very important component of the energy system; moreover, coal transportation acts as a bottleneck for the Chinese economy. To insure the security of the coal supply, China has begun to build regional strategic coal reserves at some locations, but transportation is still the fundamental way to guaranty supply security. Here, we study China's coal transportation quantitatively with a linear programming method that analyses the direction and volume of China's coal flows with the prerequisite that each province's supply and demand balance is guaranteed. First, we analyse the optimal coal transportation for the status quo coal supply and demand given the bottleneck effects that the Daqin Railway has on China's coal flow; second, we analyse the influence of future shifts in the coal supply zone in the future, finding that China's coal flows will also change, which will pressure China to construct railways and ports; and finally, we analyse the possibility of exploiting Yangtze River capacity for coal transportation. We conclude the paper with suggestions for enhancing China's coal transportation security. - Highlights: ► We use linear programming to study China's coal transportation. ► First, analyse the optimal coal flow under the status quo condition. ► Second, analyse influences of coal supply zone shifts to Neimeng and Xinjiang. ► Third, analyse the influence of using Yangtze River for coal transportation. ► At last, we give suggestions about infrastructure construction to guaranty China's long-run coal supply security.

  3. [Fractions and adsorption characteristics of phosphorus on sediments and soils in water level fluctuating zone of the Pengxi River, a tributary of the Three Gorges Reservoir].

    Science.gov (United States)

    Sun, Wen-Bin; Du, Bin; Zhao, Xiu-Lan; He, Bing-Hui

    2013-03-01

    The sediment, one of the key factors leading to the eutrophication of water bodies, is an important ecological component of natural water body. In order to investigate the morphological characteristics and moving-transiting rule of phosphorus in the sediments of the Pengxi River, a tributary of the Three Gorges Reservoir, the distributions of different phosphorus forms on the three cross-section in the sediments and three soil types of riparian zone were investigated using the sequential extraction method. The characteristics of phosphorus adsorption on the sediments were also investigated by batch experiments. The equilibrium phosphorus concentrations at zero adsorption (EPC0) on those sediments were estimated using the Henry linear models. The results show that the total phosphorus (TP) contents of these sediments and soils of riparian zone were 0.80-1.45 g x kg(-1) and 0.65-1.16 g x kg(-1), respectively. Phosphorus in sediments and soils were divided into inorganic phosphorus (IP) and organic phosphorus (Or-P), and the inorganic phosphorus was the dominant component of TP. Of the inorganic phosphorus fractions, the percentages of phosphorus bounded to calcium (Ca-P) and occluded phosphorus (O-P) from sediments were higher than 80%, implying that the contents of phosphorus were mainly influenced by their bedrocks and the sedimentary environmental conditions, not by the activities of human beings. The fractions of Ca-P and O-P were the dominant components of inorganic phosphorus in alluvial soil and purple soil, while the fraction of O-P was the highest in the paddy soil. The EPC0 values of the sediments from the sections of Huangshi, Shuangjiang and Gaoyang were 0.08, 0.13 and 0.11 mg x L(-1) respectively, but the EPC0 values of the alluvial soil, purple soil and paddy soil located in riparian zone were 0.08, 0.09 and 0.04 mg x L(-1), respectively. Correlation analysis shows that the values of EPC0 positively related to the contents of total phosphorus and clay

  4. Future demands for imported coal in Asian countries

    International Nuclear Information System (INIS)

    Kimura, T.

    1991-01-01

    This paper reports that one of the main characteristics of international coal trade in the 1980's was a much higher growth rate recorded in steam coal trade than in coking coal trade. Another was that coal import in Asia started to expand rapidly at the start of the 1980's. Increased coal imports by Asian countries is primarily attributed to growing steam coal imports. Steam coal accounted for more than two-thirds of the additional coal imports by Asian countries between 1980 and 1988. Nonetheless, coking coal still forms the largest segment of Pacific coal trade. Only in the early 1990's is steam coal trade expected to exceed coking coal trade in the Pacific

  5. Coal summit II

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    Various papers were presented on world coal trade. Papers include: Poland as a producer and exporter of coal; the dynamics of world coal trade; Cerrejon coal production perspectives; present state of the Australian coal industry; present state of the EC coal market and future prospects; prospects of US coal exports to Europe; forecast of Italian coal supply and demand through 1990; statistics from coal transportation outlook; status of world coal ports.

  6. A Comparison between Model Base Hardconstrain, Bandlimited, and Sparse-Spike Seismic Inversion: New Insights for CBM Reservoir Modelling on Muara Enim Formation, South Sumatra

    Science.gov (United States)

    Mohamad Noor, Faris; Adipta, Agra

    2018-03-01

    Coal Bed Methane (CBM) as a newly developed resource in Indonesia is one of the alternatives to relieve Indonesia’s dependencies on conventional energies. Coal resource of Muara Enim Formation is known as one of the prolific reservoirs in South Sumatra Basin. Seismic inversion and well analysis are done to determine the coal seam characteristics of Muara Enim Formation. This research uses three inversion methods, which are: model base hard- constrain, bandlimited, and sparse-spike inversion. Each type of seismic inversion has its own advantages to display the coal seam and its characteristic. Interpretation result from the analysis data shows that the Muara Enim coal seam has 20 (API) gamma ray value, 1 (gr/cc) – 1.4 (gr/cc) from density log, and low AI cutoff value range between 5000-6400 (m/s)*(g/cc). The distribution of coal seam is laterally thinning northwest to southeast. Coal seam is seen biasedly on model base hard constraint inversion and discontinued on band-limited inversion which isn’t similar to the geological model. The appropriate AI inversion is sparse spike inversion which has 0.884757 value from cross plot inversion as the best correlation value among the chosen inversion methods. Sparse Spike inversion its self-has high amplitude as a proper tool to identify coal seam continuity which commonly appears as a thin layer. Cross-sectional sparse spike inversion shows that there are possible new boreholes in CDP 3662-3722, CDP 3586-3622, and CDP 4004-4148 which is seen in seismic data as a thick coal seam.

  7. Data base for the analysis of compositional characteristics of coal seams and macerals. Final report - Part 10. Variability in the inorganic content of United States' coals: a multivariate statistical study

    Energy Technology Data Exchange (ETDEWEB)

    Glick, D.C.; Davis, A.

    1984-07-01

    The multivariate statistical techniques of correlation coefficients, factor analysis, and cluster analysis, implemented by computer programs, can be used to process a large data set and produce a summary of relationships between variables and between samples. These techniques were used to find relationships for data on the inorganic constituents of US coals. Three hundred thirty-five whole-seam channel samples from six US coal provinces were analyzed for inorganic variables. After consideration of the attributes of data expressed on ash basis and whole-coal basis, it was decided to perform complete statistical analyses on both data sets. Thirty variables expressed on whole-coal basis and twenty-six variables expressed on ash basis were used. For each inorganic variable, a frequency distribution histogram and a set of summary statistics was produced. These were subdivided to reveal the manner in which concentrations of inorganic constituents vary between coal provinces and between coal regions. Data collected on 124 samples from three stratigraphic groups (Pottsville, Monongahela, Allegheny) in the Appalachian region were studied using analysis of variance to determine degree of variability between stratigraphic levels. Most variables showed differences in mean values between the three groups. 193 references, 71 figures, 54 tables.

  8. Achievement report for fiscal 1984 on Sunshine Program. Basic research on coal type and gasification characteristics; 1984 nendo tanshu to gas ka tokusei no kiso kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-03-01

    The study of pressurized fluidized gasification of coal chars started in fiscal 1975, and a 0.2t/d unit was in operation until fiscal 1979. Since fiscal 1980, a 1t/d unit has been in operation. In fiscal 1984, an entrained bed gasification furnace was constructed, capable of high-temperature gasification of various coals, and it is now undergoing a test operation. This report consists of pressurized gasification tests for coal char, the result of a study on the effect of coal type on the char gasification reaction rate, and the result of experiments on the treatment of coal liquefaction residue, all accomplished in the 1t/d gasification unit. For the investigation of the effect of coal type, chars of 13 types of coals are subjected to reaction tests in the carbon dioxide gas, and weight reduction rates and changes in residue surface areas are determined while reaction is under way. The results are analyzed and parameters are made clear that enable a quantitative assessment of the effect of coal type on gasification reaction rates. Pulverized grains and coal liquefaction residue are blended and gasified in the fluidized bed in the presence of oxygen and steam. As the result, a gas capable of 2,000kcal/Nm{sup 3} containing 30% hydrogen and 25% carbon monoxide is acquired, when catalyst grains in the residue are segregated. (NEDO)

  9. International Coal Report's coal year 1991

    Energy Technology Data Exchange (ETDEWEB)

    McCloskey, G [ed.

    1991-05-31

    Following introductory articles on factors affecting trade in coal and developments in the freight market, tables are given for coal exports and coal imports for major countries worldwide for 1989 and 1990. Figures are also included for coal consumption in Canada and the Eastern bloc,, power station consumption in Japan, coal supply and demand in the UK, electric utility coal consumption and stocks in the USA, coal production in Australia, Canada and USA by state, and world hard coal production. A final section gives electricity production and hard coal deliveries in the EEC, sales of imported and local coal and world production of pig iron and steel.

  10. [Pollution characteristics and ecological risk assessment of heavy metals in surface sediments of Qingshan Reservoir in Lin' an City, Zhejiang Province of East China].

    Science.gov (United States)

    Zhang, Fen; Yang, Chang-Ming; Pan, Rui-Jie

    2013-09-01

    A total of 8 representative surface sediment sampling sites were collected from the Qingshan Reservoir in Lin'an City of Zhejiang Province to investigate the differences in the total concentrations of As, Cr, Cu, Ni, Mn, Pb, and Zn among the sampling sites. The different forms of the heavy metals, i. e., acid soluble, easily reducible, easily oxidizable, and residual, were determined by BCR sequential extraction method, and the pollution degrees and potential ecological risk, of the heavy metals in the surface sediments at different sampling sites of the Reservoir were assessed by using geo-accumulation index (I(geo)) and Hakanson potential ecological risk index. There existed obvious spatial differences in the total concentrations of the heavy metals in the surface sediments of the Reservoir. The sampling sites nearby the estuaries of the tributaries flowing through downtowns and heavy industrial parks to the Reservoir had obviously higher heavy metals concentrations in surface sediments, as compared to the other sampling sites. In the sediments, Mn was mainly in acid extractable form, Cu and Pb were mainly in reducible form, and As was mainly in residual form. The surface sediments at the sampling sites nearby the estuaries of the tributaries flowing through downtowns to the Reservoir had higher proportions of acid extractable and reducibles forms of the heavy metals, which would have definite potential toxic risk to aquatic organisms. Among the 7 heavy metals in the surface sediments, As showed the highest pollution degree, followed by Cu, Ni, Mn, Pb, and Zn, which were at moderate pollution degree, while Cr was at non-pollution degree, with relatively low potential ecological risk. Through the comparison of the sampling sites, it was observed that the surface sediments at the sites nearby the estuaries of Jinxi River and Hengxi River flowing through downtowns and heavy industrial parks to the Reservoir showed obviously higher heavy metals pollution degree and

  11. Report on the achievements in the Sunshine Project in fiscal 1986. Surveys on coal type selection (coal type survey); 1986 nendo tanshu sentei chosa seika hokokusho. Tanshu chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-03-01

    The purpose of the present study is to elucidate coal quality features of different types of coals and identify the relationship between the coal quality features and the liquefaction characteristics by performing liquefaction characteristic evaluation tests. Based on the result therefrom, a method is established for coal field assessment that can estimate yield of liquefaction in coal fields and coal mines to serve for selection of coal types suitable for liquefaction. Coal quality feature surveys and liquefaction characteristics evaluation tests under the standard conditions have been completed on 48 coal types including Canadian, Australian and American coals. Elucidating the coal quality features of different coals can specify parameters for the coal quality features related to the liquefaction characteristics. Coal ranks elucidate the vitrinite reflectance, structure constituent factors the vitrinite content, composite factors the volatile matter content, quantity of heat generation, and number of H/C and O/C atoms. Investigating the relationship between the coal quality features and the liquefaction characteristics can provide fundamental data for primary screening of raw material coals for liquefaction. The result of the liquefaction characteristics evaluation test under the standard conditions can be the detailed comparative data relative to data derived from the simplified liquefaction characteristics test that is performed to estimate liquefaction yield of specific coal field and coal mine. (NEDO)

  12. Converting coal

    Energy Technology Data Exchange (ETDEWEB)

    Avigliano, A. [Bedeschi (Italy)

    2006-10-15

    In September 2005, Bedeschi was commissioned to design and supply a coal unloading, conveying and storage facility for a new raw coal line system within Hatien II Cement Co. The new plant is composed of a grab unloader, a conveyor system, a storage shed with stacking and reclaiming facilities, a complete dedusting system and civil and steel structure engineering. The scope of supply includes a local fabrication portion; however, main components will be imported. The project will be completed in 21 months. The paper looks into the mechanics of loading and unloading coal. 4 figs., 4 photos.

  13. Report on the Sunshine Project in fiscal 1990. Studies on liquefaction characteristics by coal types and on engineering properties; 1990 nendo tanshu ni yoru ekika tokusei to kogakuteki busseichi ni kansuru kenkyu hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-07-01

    This paper describes the achievements at the Government Industrial Development Laboratory, Hokkaido in the Sunshine Project in fiscal 1990. Surveys were carried on different catalytic activities for co-liquefaction of various types of coals. The Ru system was found preferable in acquiring fatty family products of low boiling points. Reactions of co-liquefaction constituents do not progress independently, but have positive interaction. Adding Ru is effective in accelerating hydrogenation of condensed aromatic rings and hydrogenation of cleaving nucleus, but in view of the hydrogenating decomposition capability, the Mo-system may be better. In a liquefaction plant test, diesel oil was manufactured by reforming and improving the Yallourn coal light oil. However, the oxygen content was too high, aggravating the temperature distribution control in catalyst bed, and not having achieved the intended denitrification rate. Discussions were given on co-liquefaction of the depressurization residues of Cold Lake (CLVB[vacuum bottom])/Athabasca (ATVB) and Battle River coal. The CLCVB and ATVB were turned into lower molecules easily through hydrogenation treatment. The reaction characteristics reflected the characteristics of medium oil. Depolymerization of coal has progressed faster in ATVB. In the study on the engineering property values, discussions were given on behavior of solid particles in a bubble column, and gas hold-up of slurry. (NEDO)

  14. Effects of lithium iodide doping on devolatilization characteristics of brown coals; Yoka lithium no tenka ga kattan no kanetsu henka katei ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Muraoka, J.; Kumagai, H.; Hayashi, J.; Chiba, T. [Hokkaido University, Sapporo (Japan)

    1996-10-28

    In order to discuss effects of lithium iodide (LiI) doping on condensation structure of brown coals during heating, spectral changes were measured by using an in-situ FT-IR. It was found that the LiI doping accelerates weight reduction due to heating, and the doping effect is affected by coal structure. Both of Loy Yang (LY) coal and its LiI doped coal (DLY) had absorption intensity of the FT-IR spectra decreased with rising temperature, and the absorption center belonging to an OH group shows different shifts between the LY and DLY coals. This indicates that the LiI doping has affected the change in hydrogen bonding patterns associated with heating. Both of South Banko (SB) and LY coals had the absorption spectral intensity in the OH group decreased as the weight reduction (conversion) rate increased. Reduction in the OH groups associated with heating is caused by volatilization and condensation reaction in light-gravity fraction. However, in the case of equal conversion rate, the LiI doped coal shows higher spectral intensity than the original coal, with the LiI doping suppressing reduction in the OH groups. It appears that the doping suppresses the condensation reaction between the OH groups. 2 refs., 6 figs., 1 tab.

  15. Reservoir floodplains support distinct fish assemblages

    Science.gov (United States)

    Miranda, Leandro E.; Wigen, S. L.; Dagel, Jonah D.

    2014-01-01

    Reservoirs constructed on floodplain rivers are unique because the upper reaches of the impoundment may include extensive floodplain environments. Moreover, reservoirs that experience large periodic water level fluctuations as part of their operational objectives seasonally inundate and dewater floodplains in their upper reaches, partly mimicking natural inundations of river floodplains. In four flood control reservoirs in Mississippi, USA, we explored the dynamics of connectivity between reservoirs and adjacent floodplains and the characteristics of fish assemblages that develop in reservoir floodplains relative to those that develop in reservoir bays. Although fish species richness in floodplains and bays were similar, species composition differed. Floodplains emphasized fish species largely associated with backwater shallow environments, often resistant to harsh environmental conditions. Conversely, dominant species in bays represented mainly generalists that benefit from the continuous connectivity between the bay and the main reservoir. Floodplains in the study reservoirs provided desirable vegetated habitats at lower water level elevations, earlier in the year, and more frequently than in bays. Inundating dense vegetation in bays requires raising reservoir water levels above the levels required to reach floodplains. Therefore, aside from promoting distinct fish assemblages within reservoirs and helping promote diversity in regulated rivers, reservoir floodplains are valued because they can provide suitable vegetated habitats for fish species at elevations below the normal pool, precluding the need to annually flood upland vegetation that would inevitably be impaired by regular flooding. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  16. Automated cost modeling for coal combustion systems

    International Nuclear Information System (INIS)

    Rowe, R.M.; Anast, K.R.

    1991-01-01

    This paper reports on cost information developed at AMAX R and D Center for coal-water slurry production implemented in an automated spreadsheet (Lotus 123) for personal computer use. The spreadsheet format allows the user toe valuate impacts of various process options, coal feedstock characteristics, fuel characteristics, plant location sites, and plant sizes on fuel cost. Model flexibility reduces time and labor required to determine fuel costs and provides a basis to compare fuels manufactured by different processes. The model input includes coal characteristics, plant flowsheet definition, plant size, and market location. Based on these inputs, selected unit operations are chosen for coal processing

  17. Coal competitiveness?

    International Nuclear Information System (INIS)

    Rogeaux, B.

    2006-01-01

    Will coal electrical plants be more competitive in the coming years? Answering this one cannot be limited to merely comparing estimates based on reference electricity production costs. The competitiveness of coal will indeed depend on the final product marketed, as the MWhs are not equal: is the purpose to produce base, half-base MWh? Does the electrical equipment structure require flexible MWh (for instance in the event of significant intermittent renewable energy amounts), and therefore plants able to adjust their power rapidly? But the competitiveness of coal will also depend on many factors that will correct reference cost estimates: uncertainties, risks, externalities. These factors will need to be appreciated on a case by case basis. We introduce some of the reasoning used to better appreciate the future competitiveness of coal, and the main factors conditioning it in three contrasting regions of the world: Europe, USA, china. (author)

  18. Influence of flue gas desulfurization (FGD) installations on emission characteristics of PM2.5 from coal-fired power plants equipped with selective catalytic reduction (SCR).

    Science.gov (United States)

    Li, Zhen; Jiang, Jingkun; Ma, Zizhen; Fajardo, Oscar A; Deng, Jianguo; Duan, Lei

    2017-11-01

    Flue gas desulfurization (FGD) and selective catalytic reduction (SCR) technologies have been widely used to control the emissions of sulphur dioxide (SO 2 ) and nitrogen oxides (NO X ) from coal-fired power plants (CFPPs). Field measurements of emission characteristics of four conventional CFPPs indicated a significant increase in particulate ionic species, increasing PM 2.5 emission with FGD and SCR installations. The mean concentrations of PM 2.5 from all CFPPs tested were 3.79 ± 1.37 mg/m 3 and 5.02 ± 1.73 mg/m 3 at the FGD inlet and outlet, respectively, and the corresponding contributions of ionic species were 19.1 ± 7.7% and 38.2 ± 7.8%, respectively. The FGD was found to enhance the conversion of NH 3 slip from the SCR to NH 4 + in the PM 2.5 , together with the conversion of SO 2 to SO 4 2- , and increased the primary NH 4 + and SO 4 2- aerosol emissions by approximately 18.9 and 4.2 times, respectively. This adverse effect should be considered when updating the emission inventory of CFPPs and should draw the attention of policy-makers for future air pollution control. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Coal - 97

    International Nuclear Information System (INIS)

    Sparre, C.

    1997-01-01

    The report deals with the use of coal and coke during 1996. Some information about techniques, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from SCB have also been used. The use of steam coal for heating purposes during 1996 was 1,2 mill tons and 50% higher than in 1995. The increase is probably temporary and due to high prices of electricity because of lack of water power. The co-generation plants were the main users of coal. The minor plants have increased their use of forest fuels. Probably the use of steam coal will go down in the immediate years both in the heat generating and the co-generation plants. During the top year 1987 coal was used in 18 hotwater plants and 11 co-generation plants. 1996 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in the industry has been constant at the level 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1996 was 1,6 mill tons like the year before. 1,2 mill tons coke were produced. The coke consumption in the industry was 1,5 mill tons. 0,3 mill tons of coke were imported. The average price of steam coal imported in Sweden in 1996 was 340 SEK/ton or 2% higher than in 1995. For the world, the average import price was 51,5 USD/ton, nearly the same as the year before. The contract prices for delivery during 1997 are about equal as the end of 1996. All Swedish plants meet their emission limits of dust, SO 2 and NO x given by county administrations or concession boards

  20. An environmental data base for all Hydro-Quebec reservoirs

    International Nuclear Information System (INIS)

    Demers, C.

    1988-01-01

    Hydro-Quebec has created two management positions specifically for reservoirs, namely Reservoir Ecology Advisor and Reservoir Management Advisor. To assist management decisions, a means was required of bringing together all existing environmental information for each reservoir operated by Hydro-Quebec, including storage reservoirs, auxiliary reservoirs and forebays. A relational database using Reflex software was developed on a network of Macintosh computers. The database contains five blocks of information: general information, and physical, physiochemical, biologic and socioeconomic characteristics for each reservoir. Data will be collected on over 100 sites, and the tool will form the basis for developing a medium-range study program on reservoir ecology. The program must take into account the physical, biological and socioeconomic aspects of the environment, as well as the concerns of management personnel operating the reservoirs, the local population, reservoir users, and various government departments. 2 figs

  1. Coal -98

    International Nuclear Information System (INIS)

    Sparre, C.

    1998-01-01

    The following report deals with the use of coal and coke during 1997. Some information about technic, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from SCB have also been used. The use of steam coal for heating purposes during 1997 was 730 000 tons and about 500 000 tons lower than in 1996. The extremely high figures of 1996 were due to twice the production of electricity because of lack of hydro power. The co-generation plants were the main users of coal. The minor plants have increased their use of forest fuels. Probably the use of steam coal will go down in the immediate years both in the heat generating and the co-generating plants. Some foreign analysts, however, estimate a doubled use of coal for energy use after 2020 because of the plans to phase out the nuclear power. During the top year 1987 coal was used in 18 hot water plants and 11 co-generation plants. 1997 these figures are 2 and 8. Taxes and environmental reasons explain this trend. The use of steam coal in the industry has been constant at the level 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1997 was 1.6 mill tons like the year before. 1.2 mill tons coke were produced. The coke consumption in the industry was 1.5 Mill tons. 0.3 mill tons of coke were imported. Several other plants have plans to replace the coal with forest fuels, waste fuels and NG. Even the biggest plant, Vaesteraas, has plans to build a block for bio fuels. Helsingborg has started to use wood pellets. The pellets replace most of the coal for the heat production in the co-generation plant. Norrkoeping Kraft AB has taken a fluid bed boiler for different fuels in operation, leading to more than half the coal consumption compared with previous years. They have also rebuilt one of their travelling grates for bio fuels. Stockholm

  2. Seismic characterization of CO{sub 2} in coals

    Energy Technology Data Exchange (ETDEWEB)

    McCrank, J.; Lawton, D.C. [Calgary Univ., AB (Canada). Dept. of Geoscience, Consortium for Research in Elastic Wave Exploration Seismology

    2008-07-01

    The Mynheer coal seam was targeted for an enhanced coalbed methane (CBM) experiment. During initial testing of the reservoir permeability, 180 tonnes of carbon dioxide (CO{sub 2}) was injected into the seam. The objective of the study was to characterize the coal zones and to determine if the small volume of CO{sub 2} in the thinly bedded and seismically tuned reservoir can be detected in the 3D surface seismic data. The multi-well pilot project took place in the Pembina Field of west-central Alberta. The Ardley coals were tested for CO{sub 2} injection, enhanced CBM production, and CO{sub 2} sequestration. The seismic survey captured the condition of the reservoir after formation permeability tests. It was concluded that the anomalies seen in the seismic data can be attributed to changes in the physical properties of the coal due to CO{sub 2} adsorption. 2 refs., 5 figs.

  3. Reservoir characteristics of middle pliocene deposits and their role in the formation of oil gas deposits of Azerbaijan shelf of the south Caspian

    International Nuclear Information System (INIS)

    Veliyeva, V.A.; Kabulova, A. Ya.

    2002-01-01

    Full text :Lithology-stratigraphical peculiarities of deposits of lower stage of productive series (P S) of Middle Pliocene their reservoir properties, correlation of individual horizons within the uplifts of the south Caspian was studied. Analysis of arenosity of lower stage of PS was studied. Azerbaijan shelf of South Caspian is located within depression zone of sedimentation basin generally, of Pliocene and post-Pliocene period of time, when sedimentation was mostly intensive and occurred in conditions of more deep sea basin. Azerbaijan shelf of south Caspian covers mainly two oil-gasp-bearing region as Absheron archipelago (north, north-eastern part of region) and Baku archipelago (southern part). Analysis of arenosity along the areas of the studied region showed, that in south-eastern direction and on the south eastern subsidence of each fold, as well as on the north-eastern wing their sand percent considerably increase whereas reservoir properties of sandy interbeds are improved

  4. Coal 95

    International Nuclear Information System (INIS)

    Sparre, C.

    1995-01-01

    The report deals with the use of coal and coke in Sweden during 1994. Some information about technology, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from Statistics Sweden have also been used.The use of steam coal for heating purposes has been unchanged during 1994 at a level of 1 Mtons. The production in the cogeneration plants has been constant, but has increased for electricity production. The minor plants have increased their use of forest fuels. The use of steam coal will probably go down in the next years both for heat and cogeneration plants. During the top year 1987 coal was used in 18 hot water and 11 cogeneration plants. 1994 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in industry has been constant at the level 0.7 Mtons. The import of metallurgical coal in 1993 was 1.6 Mtons, like 1992. Import of 0.3 Mtons of coke gives the total consumption of coke in industry as 1.5 Mtons. the average price of steam coal imported to Sweden was 317 SEK/ton, 3% higher than 1993. All Swedish plants meet their emission limit of dust, SO 2 and NO x as given by county administrations or concession boards. The cogeneration plants all have some SO 2 removal system. The biggest cogeneration plant (Vaesteraas) has recently invested in a SCR NO x cleaning system. Most other plants use low NO x burners or SNR injection systems based on ammonia or urea. 2 figs, 13 tabs

  5. Achievement report for fiscal 1984 on Sunshine Program. Research on liquefaction characteristics different between coal types and on technical physical properties; 1984 nendo tanshu ni yoru ekika tokusei to kogakuteki busseichi ni kansuru kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-03-01

    Liquefaction characteristics of coal specimens, collected from many locations across the world, are determined so as to make clear the correlations between coal type and liquefaction reactivity. Conducted for this purpose are the analysis of chemical structures of the specimens, liquefaction tests in an autoclave using various catalysts and medium oils, liquefaction tests in a 0.1t/d bench plant, investigation of the constituents of the generated oil and their separation, and the secondary stabilization treatment for the commercialization of the product. The reaction tower is kept under constant conditions, the state of the liquid mixture in the reaction tower is evaluated by tracking the flow of coal out of the reaction tower after switchover from anthracene oil to coal paste, the gas flow in the reaction tower is estimated by tracking time-wise changes in the concentration level of inert gas at the reaction tower outlet port, the inert gas having been injected in pulses into the reaction system operating under the reaction conditions. For the implementation of the above-mentioned steps, a system is designed and constructed for directly collecting samples from the vapor phase section in the reaction tower operating under given reaction conditions (temperature: 400-450 degrees C, pressure 150-300kg/cm{sup 2}), and experiments are conducted to collect gas/liquid equilibrium data in the reaction tower under the given reaction conditions. (NEDO)

  6. The application of the coal grain analysis method to coal liberation studies

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, G.; Firth, B.; Adair, B. [CSIRO Earth Science & Resource Engineering Brisbane, Qld. (Australia)

    2011-07-01

    Emerging coal markets such as the use of coal for conversion to liquid fuels and its use in fuels cells and as coal water slurries in diesel engines require coal products with different coal quality specifications than those applicable to traditional coal markets of coke making and conventional power generation. As well as quantifying coals in terms of their chemical and physical properties, detailed knowledge of the mineral inclusions within the coal particles is required to identify coals that are suited to economically produce the low-ash value coals required for these markets. After mining and processing, some particles can consist of essentially pure components of a single maceral or mineral phase whilst others are composite particles that are comprised of varying amounts of macerals and minerals. The proportion of particles that are present as pure components or as composites will be a function of the characteristics of the coal and the particle size. In general, it is considered that size reduction will result in liberation and hence increased yield. The amount of liberation that occurs during crushing or grinding a coal is however coal specific. Particle characterization information provided by an optical microscopic-imaging method, Coal Grain Analysis, was used to identify coals that might benefit from additional crushing to improve recovery of clean coal by new density separation techniques and by flotation. As expected, the results of these studies suggest that the degree of liberation that is obtained is coal specific, and, hence, yield improvements are also coal specific. Hence a quantitative method of investigating this issue is required.

  7. Coal preparation

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The acid rain control legislation has prompted the Department of Energy (DOE) to seek new technology using the Clean Coal Technology program solicitation. The main goal of the program is to reduce SO 2 emissions below 9 Mt/a (10 million stpy) and NO x emission below 5.4 Mt/a (6 million stpy) by the year 2000. This would be accomplished by using precombustion, combustion, post combustion and conversion technology. Utilities are considering installing new scrubbers, switching fuel or possibly deep clean. However, the time required to implement the control technology is short. Due to the legislation, about 110 plants will have to adopt one of the approaches. This paper reports that in characterization of coal, Ames Laboratory used a scanning electron microscope- based, automated image analysis (SEM-AIA) technique to identify coal and mineral matter association. Various forms of organic sulfur were identified using peroxyacetic acid oxidation of coal. This was followed by subsequent microscopic, GC-MS, and HRMS analysis by Southern Illinois University. In ultrafine grinding of coal, it was reported by the Mining and Mineral Institute of Alabama that silica sand or flint shot used less energy compared to steel ball mills

  8. Changes in optical properties, chemistry, and micropore and mesopore characteristics of bituminous coal at the contact with dikes in the Illinois Basin

    Science.gov (United States)

    Mastalerz, Maria; Drobniak, A.; Schimmelmann, A.

    2009-01-01

    Changes in high-volatile bituminous coal (Pennsylvanian) near contacts with two volcanic intrusions in Illinois were investigated with respect to optical properties, coal chemistry, and coal pore structure. Vitrinite reflectance (Ro) increases from 0.62% to 5.03% within a distance of 5.5??m from the larger dike, and from 0.63% to 3.71% within 3.3??m from the small dike. Elemental chemistry of the coal shows distinct reductions in hydrogen and nitrogen content close to the intrusions. No trend was observed for total sulfur content, but decreases in sulfate content towards the dikes indicate thermochemical sulfate reduction (TSR). Contact-metamorphism has a dramatic effect on coal porosity, and microporosity in particular. Around the large dike, the micropore volume, after a slight initial increase, progressively decreases from 0.0417??cm3/g in coal situated 4.7??m from the intrusive contact to 0.0126??cm3/g at the contact. Strongly decreasing mesopore and micropore volumes in the altered zone, together with frequent cleat and fracture filling by calcite, indicate deteriorating conditions for both coalbed gas sorption and gas transmissibility. ?? 2008 Elsevier B.V. All rights reserved.

  9. Existing situation of hydro resources of coal reservoirs in regards to mineral coal mining and processing activities and other human activities; Situacao atual dos recursos hidricos da bacia carbonifera, face as atividades de lavra, beneficiamento e uso do carvao mineral e de outras atividades antropicas

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, Antonio Silvio J [Companhia de Pesquisas de Recursos Minerais (CPRM), Porto Alegre, RS (Brazil); Alexandre, Nadja Zim [Fundacao de Amparo ao Meio Ambiente (FATMA), Florianopolis, SC (Brazil); [Universidade do Extermo Sul Catarinense (UNESC), Criciuma, SC (Brazil)

    1997-12-31

    The coal region which is situated in the south-east of Santa Catarina State (Brazil) is best-known as the Brazilian coal capital. The progress brought to this area by the coal explotation and later by the building of a vast ceramic industrial park has been followed by an intense environmental degradation which presents few favorable conditions for the existence of a good life quality. Nowadays this region has two thirds of its underground and surface water resources degraded by activities related the coal explotation and its use. However during the past twenty-five years some new pollution resources have been settled down in this area, specially those related to the ceramic industry, metal-mechanic, chemical and farming, to name just some of them. Therefore the Companhia de Pesquisa de Recursos Minerais - CPRM, in cooperation with Fundacao do Meio Ambiente - FATMA and Universidade do Extremo Sul Catarinense - UNESC has been carrying out a project named Qualidade das Aguas Superficiais da Bacia Carbonifera. Besides, some aspects related to the underground water resources will be focused in this work for these resources have also been very polluted and by the same pollution causes as those named before. (author) 2 refs., 1 tab.

  10. Existing situation of hydro resources of coal reservoirs in regards to mineral coal mining and processing activities and other human activities; Situacao atual dos recursos hidricos da bacia carbonifera, face as atividades de lavra, beneficiamento e uso do carvao mineral e de outras atividades antropicas

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, Antonio Silvio J. [Companhia de Pesquisas de Recursos Minerais (CPRM), Porto Alegre, RS (Brazil); Alexandre, Nadja Zim [Fundacao de Amparo ao Meio Ambiente (FATMA), Florianopolis, SC (Brazil)]|[Universidade do Extermo Sul Catarinense (UNESC), Criciuma, SC (Brazil)

    1996-12-31

    The coal region which is situated in the south-east of Santa Catarina State (Brazil) is best-known as the Brazilian coal capital. The progress brought to this area by the coal explotation and later by the building of a vast ceramic industrial park has been followed by an intense environmental degradation which presents few favorable conditions for the existence of a good life quality. Nowadays this region has two thirds of its underground and surface water resources degraded by activities related the coal explotation and its use. However during the past twenty-five years some new pollution resources have been settled down in this area, specially those related to the ceramic industry, metal-mechanic, chemical and farming, to name just some of them. Therefore the Companhia de Pesquisa de Recursos Minerais - CPRM, in cooperation with Fundacao do Meio Ambiente - FATMA and Universidade do Extremo Sul Catarinense - UNESC has been carrying out a project named Qualidade das Aguas Superficiais da Bacia Carbonifera. Besides, some aspects related to the underground water resources will be focused in this work for these resources have also been very polluted and by the same pollution causes as those named before. (author) 2 refs., 1 tab.

  11. Distilling coal

    Energy Technology Data Exchange (ETDEWEB)

    Blythe, F C

    1914-09-14

    In the destructive distillation of bituminous coal, heavy hydrocarbon oil, such as petroleum, kerosine, shale oil, and heavy tar oil, obtained in some cases during the process, is added to the coal, which is then distilled under pressure and at a comparatively low temperature regulated so as to produce a large proportion of hydrocarbon oils and a small proportion of permanent gas. In one method, about 5 to 10 parts of hydrocarbon oil are mixed with 100 parts of crushed or ground coal, and the mixture is heated in a closed vessel, provided in some cases with an agitator, under a pressure of about 60 lb/in/sup 2/, and the temperature may be gradually raised to 350/sup 0/C and then to about 500/sup 0/C. The heating may be by means of superheated steam with or without external heat.

  12. Geochemical characteristics of natural gas in the hydrocarbon accumulation history, and its difference among gas reservoirs in the Upper Triassic formation of Sichuan Basin, China

    Directory of Open Access Journals (Sweden)

    Peng Wang

    2016-08-01

    Full Text Available The analysis of hydrocarbon generation, trap formation, inclusion homogenization temperature, authigenic illite dating, and ESR dating were used to understand the history of hydrocarbon accumulation and its difference among gas reservoirs in the Upper Triassic formation of Sichuan Basin. The results show the hydrocarbon accumulation mainly occurred during the Jurassic and Cretaceous periods; they could also be classified into three stages: (1 early hydrocarbon generation accumulation stage, (2 mass hydrocarbon generation accumulation stage before the Himalayan Epoch, (3 and parts of hydrocarbon adjustment and re-accumulation during Himalayan Epoch. The second stage is more important than the other two. The Hydrocarbon accumulation histories are obviously dissimilar in different regions. In western Sichuan Basin, the gas accumulation began at the deposition period of member 5 of Xujiahe Formation, and mass accumulation occurred during the early Middle Jurassic up to the end of the Late Cretaceous. In central Sichuan Basin, the accumulation began at the early Late Jurassic, and the mass accumulation occurred from the middle Early Cretaceous till the end of the Late Cretaceous. In southern Sichuan Basin, the accumulation began at the middle Late Jurassic, and the mass accumulation occurred from the middle of the Late Cretaceous to the end of the Later Cretaceous. The accumulation history of the western Sichuan Basin is the earliest, and the southern Sichuan Basin is the latest. This paper will help to understand the accumulation process, accumulation mechanism, and gas reservoir distribution of the Triassic gas reservoirs in the Sichuan Basin better. Meanwhile, it is found that the authigenic illite in the Upper Triassic formation of Sichuan Basin origin of deep-burial and its dating is a record of the later accumulation. This suggests that the illite dating needs to fully consider illite origin; otherwise the dating results may not accurately

  13. Reservoir management under consideration of stratification and hydraulic phenomena

    NARCIS (Netherlands)

    Nandalal, K.D.W.

    1995-01-01


    Reservoirs are the most important components in a water resources system. They are used to store water to extend its temporal availability. The physical, chemical and biological characteristics of water change when impounded in reservoirs. This implies the possibility of using reservoirs

  14. Kinetics of coal pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Seery, D.J.; Freihaut, J.D.; Proscia, W.M. (United Technologies Research Center, East Hartford, CT (USA)); Howard, J.B.; Peters, W.; Hsu, J.; Hajaligol, M.; Sarofim, A. (Massachusetts Inst. of Tech., Cambridge, MA (USA)); Jenkins, R.; Mallin, J.; Espindola-Merin, B. (Pennsylvania State Univ., University Park, PA (USA)); Essenhigh, R.; Misra, M.K. (Ohio State Univ., Columbus, OH (USA))

    1989-07-01

    This report contains results of a coordinated, multi-laboratory investigation of coal devolatilization. Data is reported pertaining to the devolatilization for bituminous coals over three orders of magnitude in apparent heating rate (100 to 100,000 + {degree}C/sec), over two orders of magnitude in particle size (20 to 700 microns), final particle temperatures from 400 to 1600{degree}C, heat transfer modes ranging from convection to radiative, ambient pressure ranging from near vacuum to one atmosphere pressure. The heat transfer characteristics of the reactors are reported in detail. It is assumed the experimental results are to form the basis of a devolatilization data base. Empirical rate expressions are developed for each phase of devolatilization which, when coupled to an awareness of the heat transfer rate potential of a particular devolatilization reactor, indicate the kinetics emphasized by a particular system reactor plus coal sample. The analysis indicates the particular phase of devolatilization that will be emphasized by a particular reactor type and, thereby, the kinetic expressions appropriate to that devolatilization system. Engineering rate expressions are developed from the empirical rate expressions in the context of a fundamental understanding of coal devolatilization developed in the course of the investigation. 164 refs., 223 figs., 44 tabs.

  15. Mineralogical and compositional characteristics of Late Permian coals from an area of high lung cancer rate in Xuan Wei, Yunnan, China: Occurrence and origin of quartz and chamosite

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Shifeng; Zhao, Lei; Cao, Hongzhi; Ren, Deyi [State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083 (China); Tian, Linwei [School of Public Health, Chinese University of Hong Kong, Hong Kong SAR (China); Chou, Chen-Lin [Illinois State Geological Survey (Emeritus), 615 East Peabody Drive, Champaign, IL 61820 (United States); Zhou, Yiping; Zhang, Mingquan; Wang, Jumin; Yang, Zong [Yunnan Institute of Coal Geology Prospection, Kunming 650218 (China)

    2008-12-01

    Some townships in Xuan Wei County, Yunnan Province, have one of the highest lung cancer mortality rates in China and the epidemic disease in the area has generally been attributed to the polycyclic aromatic hydrocarbons (PAHs) released from domestic coal burning. However, the cancer-causing culprit is not settled as Tian [Tian, L., 2005. Coal Combustion Emissions and Lung Cancer in Xuan Wei, China. Ph.D. thesis, University of California, Berkeley.] found nanometer quartz in these coals, soot emissions, and lung cancer tissues. We have conducted mineralogical and geochemical studies of the coals from Xuan Wei for the purpose of shedding light on the minerals which may be related to the epidemic lung cancer. In this paper, abundances, modes of occurrence, and origins of minerals and elements in the coals from two mines in Xuan Wei have been studied using optical microscope, low-temperature ashing, X-ray diffraction analysis, scanning electron microscope equipped with energy-dispersive X-ray spectrometer, and inductively-coupled plasma mass spectrometry. The minerals in the coals are mainly composed of quartz, chamosite, kaolinite, and calcite. The particle size of quartz is rather small, mostly less than 20 {mu}m and it is of authigenic origin. Chamosite occurs mainly as cell-fillings. The occurrence of quartz and chamosite indicates that they were derived from the hydrothermal fluids. Epigenetic calcite is derived from calcic fluids. Kaolinite is derived mainly from sediment source region of Kangdian Oldland to the west of coal basin. The composition of Xuan Wei coal is high in SiO{sub 2}, Fe{sub 2}O{sub 3}, TiO{sub 2}, CaO, MnO, V, Co, Ni, Cu, and Zn. The high SiO{sub 2} content is attributed to quartz, and the Fe{sub 2}O{sub 3} content to chamosite. The high Mn and low Mg contents in the coal indicate the inputs of hydrothermal fluids. CaO occurs mainly in epigenetic calcite. Elements Ti, Co, Ni, Cu, Zn, and rare earth elements were derived from the basaltic rocks

  16. Reactivity of North Bohemian coals in coprocessing of coal/oil mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Sebor, G.; Cerny, J.; Maxa, D.; Blazek, J. [Inst. of Chemical Technology, Prague (Czechoslovakia); Sykorova, I. [Inst. of Rock Structure and Mechanics, Prague (Czechoslovakia)

    1995-12-01

    Autoclave experiments with North Bohemian coal were done in order to evaluate their reactivity in coprocessing with petroleum vacuum residue, Selected coals were comprehensively characterized by using a number of analytical methods. While the coals were of similar geological origin, some of their characteristics differed largely from one coal to another. Despite the differences in physical and chemical structure, the coals provided very similar yields of desired reaction products. The yields of a heavy non- distillable fraction and/or an insoluble solid residue were, under experimental conditions, largely affected by retrogressive reactions (coking). The insoluble solid fractions were examined microscopically under polarized light.

  17. Reservoir management under consideration of stratification and hydraulic phenomena

    OpenAIRE

    Nandalal, K.D.W.

    1995-01-01


    Reservoirs are the most important components in a water resources system. They are used to store water to extend its temporal availability. The physical, chemical and biological characteristics of water change when impounded in reservoirs. This implies the possibility of using reservoirs for the control of the quality of water besides merely satisfying the quantity requirement. This study presents several techniques formulated to manage a reservoir when both quantity and quality of...

  18. Coal Mines Security System

    OpenAIRE

    Ankita Guhe; Shruti Deshmukh; Bhagyashree Borekar; Apoorva Kailaswar; Milind E.Rane

    2012-01-01

    Geological circumstances of mine seem to be extremely complicated and there are many hidden troubles. Coal is wrongly lifted by the musclemen from coal stocks, coal washeries, coal transfer and loading points and also in the transport routes by malfunctioning the weighing of trucks. CIL —Coal India Ltd is under the control of mafia and a large number of irregularities can be contributed to coal mafia. An Intelligent Coal Mine Security System using data acquisition method utilizes sensor, auto...

  19. Coal at the crossroads

    International Nuclear Information System (INIS)

    Scaroni, A.W.; Davis, A.; Schobert, H.; Gordon, R.L.; Ramani, R.V.; Frantz, R.L.

    1992-01-01

    Worldwide coal reserves are very large but coal suffers from an image of being an environmentally unfriendly and inconvenient fuel. Aspects discussed in the article include: coal's poor image; techniques for coal analysis, in particular instrumented techniques; developments in clean coal technology e.g. coal liquefaction, fluidized bed combustion, co-generation and fuel slurries; the environmental impact of mining and land reclamation; and health aspects. It is considered that coal's future depends on overcoming its poor image. 6 photos

  20. Co-combustion characteristics and blending optimization of tobacco stem and high-sulfur bituminous coal based on thermogravimetric and mass spectrometry analyses.

    Science.gov (United States)

    Zhang, Kaihua; Zhang, Kai; Cao, Yan; Pan, Wei-ping

    2013-03-01

    Despite much research on co-combustion of tobacco stem and high-sulfur coal, their blending optimization has not been effectively found. This study investigated the combustion profiles of tobacco stem, high-sulfur bituminous coal and their blends by thermogravimetric analysis. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions were also studied by thermogravimetric and mass spectrometry analyses. The results indicated that combustion of tobacco stem was more complicated than that of high-sulfur bituminous coal, mainly shown as fixed carbon in it was divided into two portions with one early burning and the other delay burning. Ignition and burnout performances, heat release performances, and gaseous pollutant emissions of the blends present variable trends with the increase of tobacco stem content. Taking into account the above three factors, a blending ratio of 0–20% tobacco stem content is conservatively proposed as optimum amount for blending. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. SILTATION IN RESERVOIRS

    African Journals Online (AJOL)

    Keywords: reservoir model, siltation, sediment, catchment, sediment transport. 1. Introduction. Sediment ... rendered water storage structures useless in less than 25 years. ... reservoir, thus reducing the space available for water storage and ...

  2. Reservoir fisheries of Asia

    International Nuclear Information System (INIS)

    Silva, S.S. De.

    1990-01-01

    At a workshop on reservoir fisheries research, papers were presented on the limnology of reservoirs, the changes that follow impoundment, fisheries management and modelling, and fish culture techniques. Separate abstracts have been prepared for three papers from this workshop

  3. Coal industry annual 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    Coal Industry Annual 1997 provides comprehensive information about US coal production, number of mines, prices, productivity, employment, productive capacity, and recoverable reserves. US Coal production for 1997 and previous years is based on the annual survey EIA-7A, Coal Production Report. This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report includes a national total coal consumption for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. 14 figs., 145 tabs.

  4. Coal industry annual 1997

    International Nuclear Information System (INIS)

    1998-12-01

    Coal Industry Annual 1997 provides comprehensive information about US coal production, number of mines, prices, productivity, employment, productive capacity, and recoverable reserves. US Coal production for 1997 and previous years is based on the annual survey EIA-7A, Coal Production Report. This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report includes a national total coal consumption for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. 14 figs., 145 tabs

  5. Coal marketing manual 1987

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This manual provides information on the international coal market in tabulated format. Statistics are presented for the Australian coal industry, exports, currency movements, world coal production, coal and coke imports and exports. Detailed information is provided on the Australian coal industry including mine specific summaries. Pricing summaries for thermal and coking coal in 1987, coal quality standards and specifications, trends in coal prices and stocks. Imports and exports for World coal and coke, details of shipping, international ports and iron and steel production. An exporters index of Australian and overseas companies with industry and government contacts is included. 15 figs., 67 tabs.

  6. Coal industry annual 1996

    International Nuclear Information System (INIS)

    1997-11-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States.This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 24 million short tons for 1996. 14 figs., 145 tabs

  7. Coal industry annual 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States.This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 24 million short tons for 1996. 14 figs., 145 tabs.

  8. Coal Industry Annual 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 21 million short tons for 1995.

  9. Coal Industry Annual 1995

    International Nuclear Information System (INIS)

    1996-10-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 21 million short tons for 1995

  10. Coal and Energy.

    Science.gov (United States)

    Bryant, Reba; And Others

    This teaching unit explores coal as an energy resource. Goals, student objectives, background information, and activity options are presented for each major section. The sections are: (1) an introduction to coal (which describes how and where coal was formed and explains the types of coal); (2) the mining of coal (including the methods and ways of…

  11. Method selection for mercury removal from hard coal

    Directory of Open Access Journals (Sweden)

    Dziok Tadeusz

    2017-01-01

    Full Text Available Mercury is commonly found in coal and the coal utilization processes constitute one of the main sources of mercury emission to the environment. This issue is particularly important for Poland, because the Polish energy production sector is based on brown and hard coal. The forecasts show that this trend in energy production will continue in the coming years. At the time of the emission limits introduction, methods of reducing the mercury emission will have to be implemented in Poland. Mercury emission can be reduced as a result of using coal with a relatively low mercury content. In the case of the absence of such coals, the methods of mercury removal from coal can be implemented. The currently used and developing methods include the coal cleaning process (both the coal washing and the dry deshaling as well as the thermal pretreatment of coal (mild pyrolysis. The effectiveness of these methods various for different coals, which is caused by the diversity of coal origin, various characteristics of coal and, especially, by the various modes of mercury occurrence in coal. It should be mentioned that the coal cleaning process allows for the removal of mercury occurring in mineral matter, mainly in pyrite. The thermal pretreatment of coal allows for the removal of mercury occurring in organic matter as well as in the inorganic constituents characterized by a low temperature of mercury release. In this paper, the guidelines for the selection of mercury removal method from hard coal were presented. The guidelines were developed taking into consideration: the effectiveness of mercury removal from coal in the process of coal cleaning and thermal pretreatment, the synergy effect resulting from the combination of these processes, the direction of coal utilization as well as the influence of these processes on coal properties.

  12. Petrological and geochemical characteristics of Palaeogene low-rank coal on the Faroe Islands: Restricted effects of alteration by basaltic lava flows

    Czech Academy of Sciences Publication Activity Database

    Kuboušková, S.; Krmíček, Lukáš; Coufalík, Pavel; Pokorný, R.

    2016-01-01

    Roč. 165, AUG (2016), s. 157-172 ISSN 0166-5162 R&D Projects: GA ČR(CZ) GA13-18482S Institutional support: RVO:68081715 ; RVO:67985831 Keywords : Faroe Island * coal composition * alteration Subject RIV: DB - Geology ; Mineralogy Impact factor: 4.783, year: 2016

  13. Numerical study of flow, combustion and emissions characteristics in a 625 MWe tangentially fired boiler with composition of coal 70% LRC and 30% MRC

    Science.gov (United States)

    Sa'adiyah, Devy; Bangga, Galih; Widodo, Wawan; Ikhwan, Nur

    2017-08-01

    Tangential fired boiler is one of the methods that can produce more complete combustion. This method applied in Suralaya Power Plant, Indonesia. However, the boiler where supposed to use low rank coal (LRC), but at a given time must be mixed with medium rank coal (MRC) from another unit because of lack of LRC coal. Accordingly to the situation, the study about choosing the right position of LRC and MRC in the burner elevation must be investigated. The composition of coal is 70%LRC / 30%MRC where MRC will be placed at the lower (A & C - Case I)) or higher (E & G - Case II) elevation as the cases in this study. The study is carried out using Computational Fluid Dynamics (CFD) method. The simulation with original case (100%LRC) has a good agreement with the measurement data. As the results, MRC is more recommended at the burner elevation A & C rather than burner elevation E & G because it has closer temperature (880 K) compared with 100%LRC and has smaller local heating area between upper side wall and front wall with the range of temperature 1900 - 2000 K. For emissions, case I has smaller NOx and higher CO2 with 104 ppm and 15,6%. Moreover, it has samller O2 residue with 5,8% due to more complete combustion.

  14. Effect of the grinding behaviour of coal blends on coal utilisation for combustion

    Energy Technology Data Exchange (ETDEWEB)

    Rubiera, F.; Arenillas, A.; Fuente, E.; Pis, J.J. [Inst. Nacional del Carbon, CSIC, Oviedo (Spain); Miles, N. [School of Chemical, Environmental and Mining Engineering, Nottingham Univ. (United Kingdom)

    1999-11-01

    Grinding of a high volatile bituminous coal was performed in three comminution devices: Raymond Mill (RM), Rolls Crusher (RC) and Ball Mill (BM). The pulverised samples were sieved to obtain four particle size fractions, and temperature-programmed combustion (TPC) was used for the evaluation of their combustion behaviour. In addition, three coals of different hardness and rank were mixed in various proportions in order to compare the combustibility characteristics of the binary coal blends with those of the individual coals. The effect of coal blending on grindability was also studied. It was found that grindability was non-additive especially when coals of very different hardgrove grindability index (HGI) were blended. The combustion studies also suggested that there exists an interaction between individual coals when they are burnt as a blend. (orig.)

  15. Reservoir Models for Gas Hydrate Numerical Simulation

    Science.gov (United States)

    Boswell, R.

    2016-12-01

    Scientific and industrial drilling programs have now providing detailed information on gas hydrate systems that will increasingly be the subject of field experiments. The need to carefully plan these programs requires reliable prediction of reservoir response to hydrate dissociation. Currently, a major emphasis in gas hydrate modeling is the integration of thermodynamic/hydrologic phenomena with geomechanical response for both reservoir and bounding strata. However, also critical to the ultimate success of these efforts is the appropriate development of input geologic models, including several emerging issues, including (1) reservoir heterogeneity, (2) understanding of the initial petrophysical characteristics of the system (reservoirs and seals), the dynamic evolution of those characteristics during active dissociation, and the interdependency of petrophysical parameters and (3) the nature of reservoir boundaries. Heterogeneity is ubiquitous aspect of every natural reservoir, and appropriate characterization is vital. However, heterogeneity is not random. Vertical variation can be evaluated with core and well log data; however, core data often are challenged by incomplete recovery. Well logs also provide interpretation challenges, particularly where reservoirs are thinly-bedded due to limitation in vertical resolution. This imprecision will extend to any petrophysical measurements that are derived from evaluation of log data. Extrapolation of log data laterally is also complex, and should be supported by geologic mapping. Key petrophysical parameters include porosity, permeability and it many aspects, and water saturation. Field data collected to date suggest that the degree of hydrate saturation is strongly controlled by/dependant upon reservoir quality and that the ratio of free to bound water in the remaining pore space is likely also controlled by reservoir quality. Further, those parameters will also evolve during dissociation, and not necessary in a simple

  16. Coal -94

    International Nuclear Information System (INIS)

    Sparre, C.

    1994-05-01

    This report deals with use of coal and coke during 1993; information about techniques, environmental questions and markets are also given. Use of steamcoal for heating purposes has been reduced about 3 % during 1993 to 1,0 mill tons. This is the case especially for the heat generating boilers. Production in co-generation plants has been constant and has increased for electricity production. Minor plants have increased their use of forest fuels, LPG and NG. Use of steamcoal will probably go down in the immediate years both in heat generating and co-generating plants. Coal-based electricity has been imported from Denmark during 1993 corresponding to about 400 000 tons of coal, when several of our nuclear plants were stopped. Use of steamcoal in the industry has been constant at 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1993 was 1,6 mill tons like the year before. 1,2 mill tons coke were produced. Coke consumption in industry was 1,4 mill tons. 0,2 mill tons of coke were imported. Average price of steamcoal imported to Sweden in 1993 was 308 SEK/ton or 13 % higher than in 1992; this can be explained by the dollar price level increasing 34% in 1993. For the world, the average import price was 50,0 USD/ton, a decrease of 6 %. The coal market during 1993 was affected by less consumption in Europe, shut downs of European mines and decreasing prices. High freight price raises in Russia has affected the Russian export and the market in northern Europe. The prices have been stabilized recently. All Swedish plants meet emission limits of dust, SO 2 and NO x . Co-generation plants all have some sort of SO 2 -removal system; the wet-dry method is mostly used. A positive effect of the recently introduced NO x -duties is a 40% reduction

  17. Coal statistics 1977

    Energy Technology Data Exchange (ETDEWEB)

    Statistical Office of the European Communities

    1978-01-01

    Presents tables of data relating to the coal market in the European Community in 1977. The tables cover hard coal production, supply and trade; briquettes; cokes; lignite, brown coal briquettes and peat; and mines and coke ovens.

  18. Australian coal yearbook 1989

    Energy Technology Data Exchange (ETDEWEB)

    Aylward, A [ed.

    1989-01-01

    This yearbook contains a mine directory; details of coal export facilities and ports; annual coal statistics; a buyers' guide; names and addresses of industry organisations and an index of coal mine owners.

  19. Coal industry annual 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-06

    Coal Industry Annual 1993 replaces the publication Coal Production (DOE/FIA-0125). This report presents additional tables and expanded versions of tables previously presented in Coal Production, including production, number of mines, Productivity, employment, productive capacity, and recoverable reserves. This report also presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for a wide audience including the Congress, Federal and State agencies, the coal industry, and the general public. In addition, Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility Power Producers who are not in the manufacturing, agriculture, mining, construction, or commercial sectors. This consumption is estimated to be 5 million short tons in 1993.

  20. Coal industry annual 1993

    International Nuclear Information System (INIS)

    1994-01-01

    Coal Industry Annual 1993 replaces the publication Coal Production (DOE/FIA-0125). This report presents additional tables and expanded versions of tables previously presented in Coal Production, including production, number of mines, Productivity, employment, productive capacity, and recoverable reserves. This report also presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for a wide audience including the Congress, Federal and State agencies, the coal industry, and the general public. In addition, Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility Power Producers who are not in the manufacturing, agriculture, mining, construction, or commercial sectors. This consumption is estimated to be 5 million short tons in 1993

  1. Economics of Developing Hot Stratigraphic Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Greg Mines; Hillary Hanson; Rick Allis; Joseph Moore

    2014-09-01

    Stratigraphic geothermal reservoirs at 3 – 4 km depth in high heat-flow basins are capable of sustaining 100 MW-scale power plants at about 10 c/kWh. This paper examines the impacts on the levelized cost of electricity (LCOE) of reservoir depth and temperature, reservoir productivity, and drillhole/casing options. For a reservoir at 3 km depth with a moderate productivity index by hydrothermal reservoir standards (about 50 L/s/MPa, 5.6 gpm/psi), an LCOE of 10c/kWh requires the reservoir to be at about 200°C. This is the upper temperature limit for pumps. The calculations assume standard hydrothermal drilling costs, with the production interval completed with a 7 inch liner in an 8.5 inch hole. If a reservoir at 4 km depth has excellent permeability characteristics with a productivity index of 100 L/s/MPa (11.3 gpm/psi), then the LCOE is about 11 c/kWh assuming the temperature decline rate with development is not excessive (< 1%/y, with first thermal breakthrough delayed by about 10 years). Completing wells with modest horizontal legs (e.g. several hundred meters) may be important for improving well productivity because of the naturally high, sub-horizontal permeability in this type of reservoir. Reducing the injector/producer well ratio may also be cost-effective if the injectors are drilled as larger holes.

  2. An index of reservoir habitat impairment

    Science.gov (United States)

    Miranda, L.E.; Hunt, K.M.

    2011-01-01

    Fish habitat impairment resulting from natural and anthropogenic watershed and in-lake processes has in many cases reduced the ability of reservoirs to sustain native fish assemblages and fisheries quality. Rehabilitation of impaired reservoirs is hindered by the lack of a method suitable for scoring impairment status. To address this limitation, an index of reservoir habitat impairment (IRHI) was developed by merging 14 metrics descriptive of common impairment sources, with each metric scored from 0 (no impairment) to 5 (high impairment) by fisheries scientists with local knowledge. With a plausible range of 5 to 25, distribution of the IRHI scores ranged from 5 to 23 over 482 randomly selected reservoirs dispersed throughout the USA. The IRHI reflected five impairment factors including siltation, structural habitat, eutrophication, water regime, and aquatic plants. The factors were weakly related to key reservoir characteristics including reservoir area, depth, age, and usetype, suggesting that common reservoir descriptors are poor predictors of fish habitat impairment. The IRHI is rapid and inexpensive to calculate, provides an easily understood measure of the overall habitat impairment, allows comparison of reservoirs and therefore prioritization of restoration activities, and may be used to track restoration progress. The major limitation of the IRHI is its reliance on unstandardized professional judgment rather than standardized empirical measurements. ?? 2010 US Government.

  3. Australian black coal statistics 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This second edition of Australian black coal statistics replaces the Joint Coal Board's publication 'Black coal in Australia'. It includes an expanded international coal trade supplement. Sections cover resources of black coal, coal supply and demand, coal production, employment and productivity of mines, export data, coal consumption and a directory of producers.

  4. 1982 Australian coal conference papers

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    This third Australian coal conference included papers discussing the market for coal, finance and investment, use of computers, mining, coal research, coal preparation and waste disposal, marketing and trade, and the transport of coal. All papers have been individually abstracted.

  5. GEOLOGIC SCREENING CRITERIA FOR SEQUESTRATION OF CO2 IN COAL: QUANTIFYING POTENTIAL OF THE BLACK WARRIOR COALBED METHANE FAIRWAY, ALABAMA

    Energy Technology Data Exchange (ETDEWEB)

    Jack C. Pashin; Richard E. Carroll; Richard H. Groshong, Jr.; Dorothy E. Raymond; Marcella McIntyre; J. Wayne Payton

    2003-01-01

    Sequestration of CO{sub 2} in coal has potential to reduce greenhouse gas emissions from coal-fired power plants while enhancing coalbed methane recovery. Data from more than 4,000 coalbed methane wells in the Black Warrior basin of Alabama provide an opportunity to quantify the carbon sequestration potential of coal and to develop a geologic screening model for the application of carbon sequestration technology. This report summarizes stratigraphy and sedimentation, structural geology, geothermics, hydrology, coal quality, gas capacity, and production characteristics of coal in the Black Warrior coalbed methane fairway and the implications of geology for carbon sequestration and enhanced coalbed methane recovery. Coal in the Black Warrior basin is distributed among several fluvial-deltaic coal zones in the Lower Pennsylvanian Pottsville Formation. Most coal zones contain one to three coal beds that are significant targets for coalbed methane production and carbon sequestration, and net coal thickness generally increases southeastward. Pottsville strata have effectively no matrix permeability to water, so virtually all flow is through natural fractures. Faults and folds influence the abundance and openness of fractures and, hence, the performance of coalbed methane wells. Water chemistry in the Pottsville Formation ranges from fresh to saline, and zones with TDS content lower than 10,000 mg/L can be classified as USDW. An aquifer exemption facilitating enhanced recovery in USDW can be obtained where TDS content is higher than 3,000 mg/L. Carbon dioxide becomes a supercritical fluid above a temperature of 88 F and a pressure of 1,074 psi. Reservoir temperature exceeds 88 F in much of the study area. Hydrostatic pressure gradients range from normal to extremely underpressured. A large area of underpressure is developed around closely spaced longwall coal mines, and areas of natural underpressure are distributed among the coalbed methane fields. The mobility and

  6. Effective Stress Law in Unconventional Reservoirs under Different Boundary Conditions

    Science.gov (United States)

    Saurabh, S.; Harpalani, S.

    2017-12-01

    Unconventional reservoirs have attracted a great deal of research interest worldwide during the past two decades. Low permeability and specialized techniques required to exploit these resources present opportunities for improvement in both production rates and ultimate recovery. Understanding subsurface stress modifications and permeability evolution are valuable when evaluating the prospects of unconventional reservoirs. These reservoir properties are functions of effective stress. As a part of this study, effective stress law, specifically the variation of anisotropic Biot's coefficient under various boundary conditions believed to exist in gas reservoirs by different researchers, has been established. Pressure-dependent-permeability (PdK) experiments were carried out on San Juan coal under different boundary conditions, that is, uniaxial strain condition and constant volume condition. Stress and strain in the vertical and horizontal directions were monitored throughout the experiment. Data collected during the experiments was used to determine the Biot's coefficient in vertical and horizontal directions under these two boundary conditions, treating coal as transversely isotropic. The variation of Biot's coefficient was found to be well correlated with the variation in coal permeability. Based on the estimated values of Biot's coefficients, a theory of variation in its value is presented for other boundary conditions. The findings of the study shed light on the inherent behavior of Biot's coefficient under different reservoir boundary conditions. This knowledge can improve the modeling work requiring estimation of effective stress in reservoirs, such as, pressure-/stress- dependent permeability. At the same time, if the effective stresses are known with more certainty by other methods, it enables assessment of the unknown reservoir boundary conditions.

  7. Key technology for treating slack coal blockage in CBM recovery: A case study from multi-lateral horizontal wells in the Qinshui Basin

    Directory of Open Access Journals (Sweden)

    Yong Yang

    2016-01-01

    Full Text Available Due to the nature of coal bed, slack coal production is inevitable in gas recovery sby water drainage. When coalbed methane (CBM wells are reentered after low energy exploitation and shut-in, the negative effect of slack coal production on productivity of CBM is irreversible. In this paper, the CBM occurrence characteristics and multi-lateral horizontal well trajectory in the Qinshui Basin, Shanxi Province, were analyzed. In the multi-lateral horizontal wells, the expected gas production rate could not be reached and the production rate after shut-in maintenance could not restore to the level before shut-in. The reason for these issues is that migration pathways in the reservoirs are blocked by slack coal deposits, while formation water and slack coal deposit accumulated at the troughs of horizontal sections enlarge the resistance for gas to flow into the bottom hole. Furthermore, three key technologies to deal with slack coal blockage were proposed. Firstly, CBM horizontal well trajectory should follow the principle of keeping the wellbores smooth and updip instead of being “wavy”, on the premise of guaranteeing CBM drilling rate. Secondly, the cavities of production wells, as an important part of multi-lateral horizontal wells, are capable of settling sand, and can be used for gas–liquid–solid separation. And thirdly, a tree-like horizontal well with its main hole set on stable seam top or floor, provides a stable well flushing passage for coal powder. This research provides a useful attempt in solving the problem of slack coal production in gas recovery by water drainage.

  8. Reservoir Identification: Parameter Characterization or Feature Classification

    Science.gov (United States)

    Cao, J.

    2017-12-01

    The ultimate goal of oil and gas exploration is to find the oil or gas reservoirs with industrial mining value. Therefore, the core task of modern oil and gas exploration is to identify oil or gas reservoirs on the seismic profiles. Traditionally, the reservoir is identify by seismic inversion of a series of physical parameters such as porosity, saturation, permeability, formation pressure, and so on. Due to the heterogeneity of the geological medium, the approximation of the inversion model and the incompleteness and noisy of the data, the inversion results are highly uncertain and must be calibrated or corrected with well data. In areas where there are few wells or no well, reservoir identification based on seismic inversion is high-risk. Reservoir identification is essentially a classification issue. In the identification process, the underground rocks are divided into reservoirs with industrial mining value and host rocks with non-industrial mining value. In addition to the traditional physical parameters classification, the classification may be achieved using one or a few comprehensive features. By introducing the concept of seismic-print, we have developed a new reservoir identification method based on seismic-print analysis. Furthermore, we explore the possibility to use deep leaning to discover the seismic-print characteristics of oil and gas reservoirs. Preliminary experiments have shown that the deep learning of seismic data could distinguish gas reservoirs from host rocks. The combination of both seismic-print analysis and seismic deep learning is expected to be a more robust reservoir identification method. The work was supported by NSFC under grant No. 41430323 and No. U1562219, and the National Key Research and Development Program under Grant No. 2016YFC0601

  9. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...... dispersion equation in modeling the transport and the deposition of reservoir fines. It successfully predicts the unsymmetrical concentration profiles and the hyperexponential deposition in experiments....

  10. Coal Tar and Coal-Tar Pitch

    Science.gov (United States)

    Learn about coal-tar products, which can raise your risk of skin cancer, lung cancer, and other types of cancer. Examples of coal-tar products include creosote, coal-tar pitch, and certain preparations used to treat skin conditions such as eczema, psoriasis, and dandruff.

  11. Coal gasification plant

    Energy Technology Data Exchange (ETDEWEB)

    1977-09-29

    The proposal concerns a stage in the process of cooling the synthetic gas produced in a coal gasification plant at temperatures above 900/sup 0/C. The purpose is to keep the convection heating surface of the subsequent waste heat plant free of dirt. According to the invention, the waste heat plant has a radiation area connected before it, on the heating surfaces of which the slack carried over solidifies. This radiation area has a hydraulic and thermal cleaning system, which can be raised or lowered in a water bath. The subclaims concern all the constructional characteristics of this cleaning system, which causes the solidified slack to crack.

  12. Mercury in coal and the impact of coal quality on mercury emissions from combustion systems

    International Nuclear Information System (INIS)

    Kolker, Allan; Senior, Constance L.; Quick, Jeffrey C.

    2006-01-01

    The proportion of Hg in coal feedstock that is emitted by stack gases of utility power stations is a complex function of coal chemistry and properties, combustion conditions, and the positioning and type of air pollution control devices employed. Mercury in bituminous coal is found primarily within Fe-sulfides, whereas lower rank coal tends to have a greater proportion of organic-bound Hg. Preparation of bituminous coal to reduce S generally reduces input Hg relative to in-ground concentrations, but the amount of this reduction varies according to the fraction of Hg in sulfides and the efficiency of sulfide removal. The mode of occurrence of Hg in coal does not directly affect the speciation of Hg in the combustion flue gas. However, other constituents in the coal, notably Cl and S, and the combustion characteristics of the coal, influence the species of Hg that are formed in the flue gas and enter air pollution control devices. The formation of gaseous oxidized Hg or particulate-bound Hg occurs post-combustion; these forms of Hg can be in part captured in the air pollution control devices that exist on coal-fired boilers, without modification. For a given coal type, the capture efficiency of Hg by pollution control systems varies according to type of device and the conditions of its deployment. For bituminous coal, on average, more than 60% of Hg in flue gas is captured by fabric filter (FF) and flue-gas desulfurization (FGD) systems. Key variables affecting performance for Hg control include Cl and S content of the coal, the positioning (hot side vs. cold side) of the system, and the amount of unburned C in coal ash. Knowledge of coal quality parameters and their effect on the performance of air pollution control devices allows optimization of Hg capture co-benefit

  13. First assessment of the ecological status of Karaoun reservoir, Lebanon

    International Nuclear Information System (INIS)

    Fadel, A.; Lemaire, B.; Vinc on Leite, B.; Tassin, B.; Amacha, N.; Slim, K.; Atoui, A.

    2014-01-01

    Many reservoirs have been constructed throughout the world during the 20th century, with many also suffering from eutrophication. The resulting increased phytoplankton biomass in reservoirs impairs their use. Except for Lake Kinneret, the environmental status of lakes and reservoirs in the Middle East is poorly documented. Karaoun reservoir, also known as Qaroun, Qaraoun or Qarun, is the largest water body in Lebanon, having been constructed for irrigation and hydropower production. This present study reviews Karaoun reservoir, including its characteristics, uses, water quality and phytoplankton succession, to assess the environmental status of the reservoir on the basis of the few existing previous publications about the reservoir. Since 2004, which is 39 years after its construction, the reservoir is considered to be hypereutrophic, with low phytoplankton biodiversity and regular blooms of toxic cyanobacteria. The nutrient and trace metal concentrations would not prevent use of the reservoir for a drinking water supply for Beirut, as is currently being planned, although not all the micropollutants in the lake were documented. Karaoun reservoir is compared to other monitored lakes and reservoirs around the Mediterranean Sea. They share annual toxic cyanobacteria blooms of Aphanizomenon ovalisporum and of Microcystis aeruginosa. The phytoplankton composition and succession of Karaoun reservoir is more similar to El Gergal reservoir (Spain) than nearby natural lakes such as Lake Kinneret (Israel) and Lake Trichonis (Greece). Phytoplankton diversity in Karaoun reservoir was the lowest, due to higher nutrient concentrations and a larger decrease in water level in the dry season. Karaoun reservoir represents an interesting example of the potential response of the phytoplankton community in other lakes and reservoirs during the drought periods expected to occur as a result of global climate change. (author)

  14. Record coking coal settlements

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, C.

    2005-02-01

    The US$100/tonne psychological barrier in coking coal prices has been well and truly smashed. The article examines developments in coal pricing. It includes quotes from many senior executives in the coal industry as collected at McCloskey's Australian Coal.04 conference held in Sydney, 18-19 November 2004. 2 photos.

  15. COAL Conference Poster

    OpenAIRE

    Brown, Taylor Alexander; McGibbney, Lewis John

    2017-01-01

    COAL Conference Poster This archive contains the COAL conference poster for the AGU Fall Meeting 2017 by Taylor Alexander Brown. The Inkscape SVG source is available at https://github.com/capstone-coal/coal-conference-poster/ under the Creative Commons Attribution-ShareAlike 4.0 International license.

  16. Coal graders in Czechoslovakian mines

    Energy Technology Data Exchange (ETDEWEB)

    Vasek, J.; Klimek, M.

    1980-01-01

    Problems related to sections of the area of application of graders depending on different mining and geological mining-engineering factors are examined. The principal factors are selected from a general group of influencing factors: dip angle of a formation, separability (shear ability) of coal, characteristics of country rocks, adhesion of coal to rock, tectonic fracturing of a seam, and thickness of a formation. Based on practical and theoretical studies all of the principal factors have been categorized. This allows one to obtain an objective picture of the possibility of using graders under specific conditions by comparing different factors.

  17. Coal option. [Shell Co

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    This paper notes the necessity of developing an international coal trade on a very large scale. The role of Shell in the coal industry is examined; the regions in which Shell companies are most active are Australia, Southern Africa, Indonesia; Europe and North America. Research is being carried out on marketing and transportation, especially via slurry pipelines; coal-oil emulsions; briquets; fluidized-bed combustion; recovery of coal from potential waste material; upgrading of low-rank coals; unconventional forms of mining; coal conversion (the Shell/Koppers high-pressure coal gasification process). Techniques for cleaning flue gas (the Shell Flue Gas Desulfurization process) are being examined.

  18. Concerning coal: an anthology

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, M.; Hawse, M.L.; Maloney, P.J. [eds.

    1997-12-31

    The anthology takes a humanistic look at coal mining in Illinois. One of its goals is to increase public awareness of coal in American society; it also seeks to enhance understanding of the historical aspects of coal and to study the impact of coal on mining families. Many of the 25 selections in the anthology come from Coal Research Center publications, `Concerning coal` and `Mineral matters`. Articles are arranged in three parts entitled: life in the mining community; mining in folklore, story telling, literature, art and music; and technology as it affected the people of the coal fields. 117 refs., 25 photos. 1 map.

  19. Coal gasification. Quarterly report, April--June 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    The conversion of coal to high-Btu gas requires a chemical and physical transformation of solid coal. However, because coal has widely differing chemical and physical properties, depending on where it is mined, it is difficult to process. Therefore, to develop the most suitable techniques for gasifying coal, ERDA, together with the American Gas Association, is sponsoring the development of several advanced conversion processes. Although the basic coal-gasification chemical reactions are the same for each process, the processes under development have unique characteristics. A number of the processes for converting coal to high Btu and to low Btu gas have reached the pilot plant stage. The responsibility for designing, constructing and operating each of these pilot plants is defined and progress on each during the quarter is described briefly. The accumulation of data for a coal gasification manual and the development of mathematical models of coal gasification processes are reported briefly. (LTN)

  20. Coal information 1995

    International Nuclear Information System (INIS)

    1996-01-01

    This volume is a comprehensive reference book on current world coal market trends and long-term prospects to 2010. It contains an in-depth analysis of the 1995 international coal market covering prices, demand, trade, supply and production capacity as well as over 450 pages of country specific statistics on OECD and key non-OECD coal producing and consuming countries. The book also includes a summary of environmental policies on climate change and on coal-related air quality issues as well as essential facts on coal-fired power stations in coal-importing regions, on coal ports world-wide and on emission standards for coal-fired boilers in OECD countries. Coal Information is one of a series of annual IEA statistical publications on major energy sources; other reports are Oil and Gas Information and Electricity Information. Coal Information 1995 is published in July 1996. (author)

  1. Coal yearbook 1993

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This book is the first coal yearbook published by ATIC (France). In a first chapter, economical context of coal worldwide market is analyzed: comparative evaluations on coal exports and imports, coal industry, prices, production in USA, Australia, South Africa, China, former USSR, Poland, Colombia, Venezuela and Indonesia are given. The second chapter describes the french energy context: national coal production, imports, sectorial analysis, maritime transport. The third chapter describes briefly the technologies of clean coal and energy saving developed by Charbonnages de France: fossil-fuel power plants with combined cycles and cogeneration, fluidized beds for the recovery of coal residues, recycling of agricultural wastes (sugar cane wastes) in thermal power plant, coal desulfurization for air pollution abatement. In the last chapter, statistical data on coal, natural gas and crude oil are offered: world production, world imports, world exports, french imports, deliveries to France, coal balance, french consumption of primary energy, power generation by fuel type

  2. Geochemical characteristics of dissolved rare earth elements in acid mine drainage from abandoned high-As coal mining area, southwestern China.

    Science.gov (United States)

    Li, Xuexian; Wu, Pan

    2017-09-01

    Acid mine drainage (AMD) represents a major source of water pollution in the small watershed of Xingren coalfield in southwestern Guizhou Province. A detailed geochemical study was performed to investigate the origin, distribution, and migration of REEs by determining the concentrations of REEs and major solutes in AMD samples, concentrations of REEs in coal, bedrocks, and sediment samples, and modeling REEs aqueous species. The results highlighted that all water samples collected in the mining area are identified as low pH, high concentrations of Fe, Al, SO 4 2- and distinctive As and REEs. The spatial distributions of REEs showed a peak in where it is nearby the location of discharging of AMD, and then decrease significantly with distance away from the mining areas. Lots of labile REEs have an origin of coal and bedrocks, whereas the acid produced by the oxidation of pyrite is a prerequisite to cause the dissolution of coal and bedrocks, and then promoting REEs release in AMD. The North American Shale Composite (NASC)-normalized REE patterns of coal and bedrocks are enriched in light REEs (LREEs) and middle REEs (MREEs) relative to heavy REEs (HREEs). Contrary to these solid samples, AMD samples showed slightly enrichment of MREEs compared with LREEs and HREEs. This behavior implied that REEs probably fractionate during acid leaching, dissolution of bedrocks, and subsequent transport, so that the MREEs is primarily enriched in AMD samples. Calculation of REEs inorganic species for AMD demonstrated that sulfate complexes (Ln(SO 4 ) + and Ln(SO 4 ) 2 - ) predominate in these species, accounting for most of proportions for the total REEs species. The high concentrations of dissolved SO 4 2- and low pH play a decisive role in controlling the presence of REEs in AMD, as these conditions are necessary for formation of stable REEs-sulfate complexes in current study. The migration and transportation of REEs in AMD are more likely constrained by adsorption and co

  3. Reservoir Engineering Management Program

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.; Schwarz, W.J.

    1977-12-14

    The Reservoir Engineering Management Program being conducted at Lawrence Berkeley Laboratory includes two major tasks: 1) the continuation of support to geothermal reservoir engineering related work, started under the NSF-RANN program and transferred to ERDA at the time of its formation; 2) the development and subsequent implementation of a broad plan for support of research in topics related to the exploitation of geothermal reservoirs. This plan is now known as the GREMP plan. Both the NSF-RANN legacies and GREMP are in direct support of the DOE/DGE mission in general and the goals of the Resource and Technology/Resource Exploitation and Assessment Branch in particular. These goals are to determine the magnitude and distribution of geothermal resources and reduce risk in their exploitation through improved understanding of generically different reservoir types. These goals are to be accomplished by: 1) the creation of a large data base about geothermal reservoirs, 2) improved tools and methods for gathering data on geothermal reservoirs, and 3) modeling of reservoirs and utilization options. The NSF legacies are more research and training oriented, and the GREMP is geared primarily to the practical development of the geothermal reservoirs. 2 tabs., 3 figs.

  4. ACR coal 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This publication is a comprehensive reference document on production, exports, prices and demand of coal in world markets. A forecast of demand by coal type and country up to the year 2000 is provided. Statistics of the Australian export industry are complemented by those of South Africa, USA, Canada, Indonesia, China, C.I.S. and Colombia. A very comprehensive coal quality specification for nearly all the coal brands exported from Australia, as well as leading non-Australian coal brands, is included.

  5. Assessing coal burnout

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, A. [Pacific Power, Sydney, NSW (Australia)

    1999-11-01

    Recent research has allowed a quantitative description of the basic process of burnout for pulverized coals to be made. The Cooperative Research Centre for Black Coal Utilization has built on this work to develop a coal combustion model which will allow plant engineers and coal company representatives to assess their coals for combustion performance. The paper describes the model and its validation and outlines how it is run. 2 figs.

  6. An experimental study of relative permeability hysteresis, capillary trapping characteristics, and capillary pressure of CO2/brine systems at reservoir conditions

    Science.gov (United States)

    Akbarabadi, Morteza

    We present the results of an extensive experimental study on the effects of hysteresis on permanent capillary trapping and relative permeability of CO2/brine and supercritical (sc)CO2+SO2/brine systems. We performed numerous unsteady- and steady-state drainage and imbibition full-recirculation flow experiments in three different sandstone rock samples, i.e., low and high-permeability Berea, Nugget sandstones, and Madison limestone carbonate rock sample. A state-of-the-art reservoir conditions core-flooding system was used to perform the tests. The core-flooding apparatus included a medical CT scanner to measure in-situ saturations. The scanner was rotated to the horizontal orientation allowing flow tests through vertically-placed core samples with about 3.8 cm diameter and 15 cm length. Both scCO2 /brine and gaseous CO2 (gCO2)/brine fluid systems were studied. The gaseous and supercritical CO2/brine experiments were carried out at 3.46 and 11 MPa back pressures and 20 and 55°C temperatures, respectively. Under the above-mentioned conditions, the gCO2 and scCO2 have 0.081 and 0.393 gr/cm3 densities, respectively. During unsteady-state tests, the samples were first saturated with brine and then flooded with CO2 (drainage) at different maximum flow rates. The drainage process was then followed by a low flow rate (0.375 cm 3/min) imbibition until residual CO2 saturation was achieved. Wide flow rate ranges of 0.25 to 20 cm3/min for scCO2 and 0.125 to 120 cm3min for gCO2 were used to investigate the variation of initial brine saturation (Swi) with maximum CO2 flow rate and variation of trapped CO2 saturation (SCO2r) with Swi. For a given Swi, the trapped scCO2 saturation was less than that of gCO2 in the same sample. This was attributed to brine being less wetting in the presence of scCO2 than in the presence of gCO 2. During the steady-state experiments, after providing of fully-brine saturated core, scCO2 was injected along with brine to find the drainage curve and as

  7. Petrography and rank of the Bhangtar coals, southeastern Bhutan

    Energy Technology Data Exchange (ETDEWEB)

    Pareek, H S [BH23, Meerut (India)

    1990-07-01

    In Bhutan, a potential coal deposit is exposed at Bhangtar in the 'landslide zone'. Nineteen coal seams are encountered in this area, and occur in the Lower Gondwana Supergroup preserved in between the Main Boundary Fault and the Thrust. The coal is low in moisture, {lt}1.76%, but the coal cores show moisture values of 3.16%. The ash content is up to 48.87% and increases substantially in the younger seams. The volatile content (on a pure coal basis) ranges from 23.38% to 41.02%. The sulphur content is less than 0.61%. The coals are non-coking. The amount of trace elements in the coal is quite low. The average petrographic composition of the Bhangtar coal is vitrinite - 31%, exinite - 2%, inertinite - 31%, and mineral and shaly matter - 36%, the vitrinite proportion decreases from the older to the younger seams, which are shaly. an age can be assigned to the Bhangtar coal. Based on oil reflectance, the rank of the coal is metalignitous to hypobituminous. The average microlithotype composition of the coal is vitrite - 30%, clarite - 1%, vitrinertite V - 14%, vitrinertite I - 11%, durite - 3%, fusite - 14%, and carbominerite - 27%. Vitrite decreases in proportion towards the younger seams, 'intermediates' show a concomitant increase, while durite and fusite remain constant. Carbonaceous shale contains fragmentary inertinite and vitrinite macerals and is interlayered with micro-bands of shaly coal which is characterised by abundant fragments of fusinite and vitrinite. The coal is very fragile and thus amenable to economic beneficiation. The coal is used as fuel in electric power plants. The Bhangtar coal is characteristically distinct from the Gondwana coals of India in petrography and rank, but correlates petrographically with the Kameng coals of Arunachal Pradesh, India. 18 refs., 4 figs., 8 tabs., 3 plates.

  8. Demographic variables in coal miners’ safety attitude

    Science.gov (United States)

    Yin, Wen-wen; Wu, Xiang; Ci, Hui-Peng; Qin, Shu-Qi; Liu, Jia-Long

    2017-03-01

    To change unsafe behavior through adjusting people’s safety attitudes has become an important measure to prevent accidents. Demographic variables, as influential factors of safety attitude, are fundamental and essential for the research. This research does a questionnaire survey among coal mine industry workers, and makes variance analysis and correlation analysis of the results in light of age, length of working years, educational level and experiences of accidents. The results show that the coal miners’ age, length of working years and accident experiences correlate lowly with safety attitudes, and those older coal miners with longer working years have better safety attitude, as coal miners without experiences of accident do.However, educational level has nothing to do with the safety attitude. Therefore, during the process of safety management, coal miners with different demographic characteristics should be put more attention to.

  9. Coking coal of Checua Lenguazaque area

    International Nuclear Information System (INIS)

    Arboleda Otalora, Carlos Ariel

    1987-06-01

    In this report a summary of the main characteristics of the coal of the area of Checua-Samaca is presented. Using the main works carried out on this area, the most important geologic, physical-chemical, technological and petrographic aspects are compiled that are considered essential to carry out a technical evaluation of these coal and all the analyses they take to conclude that in this area, bituminous coal are presented with very good coking properties, on the other hand, it is demonstrated by the use that is given to the coal extracted by the small existent mining. However, keeping in mind the demands of the international market of the coking coal, it becomes necessary to improve the existent geologic information to be able to make reliable stratigraphic correlations

  10. Engineering characteristics of the improved soil by deep mixing method using coal ash; Sekitanbai wo riyoshita FGC shinso kongo shori koho ni yoru kairyodo no kogakuteki seishitsu to kongo no tenbo ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T [Center for Coal Utilization, Japan, Tokyo (Japan); Azuma, K; Watanabe, M [Electric Power Development Co. Ltd., Tokyo (Japan)

    1996-09-01

    Japan currently produces about six million tons of coal ash annually, whose effective bulk utilization to earth engineering materials is an important issue of technological development. A slurry may be made by mixing the following three kinds of materials: fly ash discharged from power plants exclusively burning dust coal (F), gypsum generated as a by-product in a stack gas desulfurizing process (G), and commercially available cement (C). The slurry would be called an FGC slurry taking the first letters of the materials. This paper presents the results of laboratory tests, in-situ execution tests and centrifuge model testing on engineering characteristics of soils improved by the FGC slurry when the slurry is applied to implementing the deep mixing method. As a result, a large number of findings were obtained including the following matters: the FGC deep mixing method makes it possible to improve ground beds having small deformation coefficient with the same accuracy as in the cement-based deep mixing (CDM) method at strengths lower than 5 kg/cm {sup 2} which is difficult with the CDM method, not to speak of strengths equivalent to that is possible with the normal CDM method; and development of a ground bed with improved strength is possible without being governed by quality and kinds of the fly ash. 1 ref., 23 figs., 5 tabs.

  11. Effect of site on sedimentological characteristics and metal pollution in two semi-enclosed embayments of great freshwater reservoir: Lake Nasser, Egypt

    Science.gov (United States)

    Farhat, Hassan I.; Aly, Walid

    2018-05-01

    This study was carried out to assess the effect of site on the spatial variations of sedimentological characteristics and heavy metal pollution of two semi-enclosed embayments of Lake Nasser. Grain Size, texture and mode of transportation as well as some heavy metals and organic matter were assessed in sediment samples from those embayments. The results indicated that the grain size of the lake sediments was affected by site variation. Moreover, heavy metal distribution in the sediments was mainly directed by grain size distribution and organic matter, though, the organic matter was more critical than grain size in controlling heavy metals distribution in each embayment. The main source of heavy metals in studied embayments was concluded to be the metals brought with flood waters rather than being of anthropogenic origin. The results also indicated the association of studied metals with Fe and Mn oxides of suspended matters and dissolved solids which come with flood water and trapped and settled to the bottom sediment in the stagnation period. Measured indices indicated that southern embayment is more polluted than northern one, which could be explained on the basis that the southern embayment reserves larger amounts of suspended matter coming with the flood than northern embayment.

  12. Sediment management for reservoir

    International Nuclear Information System (INIS)

    Rahman, A.

    2005-01-01

    All natural lakes and reservoirs whether on rivers, tributaries or off channel storages are doomed to be sited up. Pakistan has two major reservoirs of Tarbela and Managla and shallow lake created by Chashma Barrage. Tarbela and Mangla Lakes are losing their capacities ever since first impounding, Tarbela since 1974 and Mangla since 1967. Tarbela Reservoir receives average annual flow of about 62 MAF and sediment deposits of 0.11 MAF whereas Mangla gets about 23 MAF of average annual flows and is losing its storage at the rate of average 34,000 MAF annually. The loss of storage is a great concern and studies for Tarbela were carried out by TAMS and Wallingford to sustain its capacity whereas no study has been done for Mangla as yet except as part of study for Raised Mangla, which is only desk work. Delta of Tarbala reservoir has advanced to about 6.59 miles (Pivot Point) from power intakes. In case of liquefaction of delta by tremor as low as 0.12g peak ground acceleration the power tunnels I, 2 and 3 will be blocked. Minimum Pool of reservoir is being raised so as to check the advance of delta. Mangla delta will follow the trend of Tarbela. Tarbela has vast amount of data as reservoir is surveyed every year, whereas Mangla Reservoir survey was done at five-year interval, which has now been proposed .to be reduced to three-year interval. In addition suspended sediment sampling of inflow streams is being done by Surface Water Hydrology Project of WAPDA as also some bed load sampling. The problem of Chasma Reservoir has also been highlighted, as it is being indiscriminately being filled up and drawdown several times a year without regard to its reaction to this treatment. The Sediment Management of these reservoirs is essential and the paper discusses pros and cons of various alternatives. (author)

  13. Global Carbon Reservoir Oxidative Ratios

    Science.gov (United States)

    Masiello, C. A.; Gallagher, M. E.; Hockaday, W. C.

    2010-12-01

    Photosynthesis and respiration move carbon and oxygen between the atmosphere and the biosphere at a ratio that is characteristic of the biogeochemical processes involved. This ratio is called the oxidative ratio (OR) of photosynthesis and respiration, and is defined as the ratio of moles of O2 per moles of CO2. This O2/CO2 ratio is a characteristic of biosphere-atmosphere gas fluxes, much like the 13C signature of CO2 transferred between the biosphere and the atmosphere has a characteristic signature. OR values vary on a scale of 0 (CO2) to 2 (CH4), with most ecosystem values clustered between 0.9 and 1.2. Just as 13C can be measured for both carbon fluxes and carbon pools, OR can also be measured for fluxes and pools and can provide information about the processes involved in carbon and oxygen cycling. OR values also provide information about reservoir organic geochemistry because pool OR values are proportional to the oxidation state of carbon (Cox) in the reservoir. OR may prove to be a particularly valuable biogeochemical tracer because of its ability to couple information about ecosystem gas fluxes with ecosystem organic geochemistry. We have developed 3 methods to measure the OR of ecosystem carbon reservoirs and intercalibrated them to assure that they yield accurate, intercomparable data. Using these tools we have built a large enough database of biomass and soil OR values that it is now possible to consider the implications of global patterns in ecosystem OR values. Here we present a map of the natural range in ecosystem OR values and begin to consider its implications. One striking pattern is an apparent offset between soil and biospheric OR values: soil OR values are frequently higher than that of their source biomass. We discuss this trend in the context of soil organic geochemistry and gas fluxes.

  14. Coal information 1996

    International Nuclear Information System (INIS)

    1997-01-01

    Coal Information (1997 edition) is the latest edition of a publication that has been produced annually by the IEA since 1983. The report is intended to provide both Member countries of the OECD and those employed in all sectors of the coal industry with information on current world coal market trends and long-term prospects. It includes information on coal prices, demand, trade, supply, production capacity, transport, environmental issues (including emission standards for coal-fired boilers), coal ports, coal-fired power stations and coal used in non -OECD countries. Part I of the publication contains a wide ranging review of world coal market developments in 1996 and current prospects to 2010. The review is based on historical data of OECD energy supply and demand, data on other world regions, projections of OECD coal supply, demand and trade and information provided by the CIAB. Part II provides, in tabular and graphical form, a more detailed and comprehensive statistical picture of coal developments and future prospects for coal in the OECD, by region and for individual Member countries. Readers interested in projections are strongly advised to read the notes for individual countries in Principles and Definitions in Part II. Coal statistics for non-OECD countries are presented in Part III of the book. Summary data are available on hard coal supply and end-use statistics for about 40 countries and regions world-wide. Data are based on official national submissions to the United Nations in Geneva and New York, national energy publications, information provided to the IEA Secretariat by national statistical offices as well as other unofficial Secretariat sources. Further information on coal used in non-OECD countries is published annually by the IEA in Energy Statistics and Balances of Non-OECD Countries. Also included in Part III are the Survey of Coal Ports world-wide and the Survey of Coal-fired Power Stations in coal-importing countries

  15. Optimising reservoir operation

    DEFF Research Database (Denmark)

    Ngo, Long le

    Anvendelse af optimeringsteknik til drift af reservoirer er blevet et væsentligt element i vandressource-planlægning og -forvaltning. Traditionelt har reservoirer været styret af heuristiske procedurer for udtag af vand, suppleret i en vis udstrækning af subjektive beslutninger. Udnyttelse af...... reservoirer involverer en lang række interessenter med meget forskellige formål (f.eks. kunstig vanding, vandkraft, vandforsyning mv.), og optimeringsteknik kan langt bedre lede frem til afbalancerede løsninger af de ofte modstridende interesser. Afhandlingen foreslår en række tiltag, hvormed traditionelle...

  16. China's Coal: Demand, Constraints, and Externalities

    Energy Technology Data Exchange (ETDEWEB)

    Aden, Nathaniel; Fridley, David; Zheng, Nina

    2009-07-01

    This study analyzes China's coal industry by focusing on four related areas. First, data are reviewed to identify the major drivers of historical and future coal demand. Second, resource constraints and transport bottlenecks are analyzed to evaluate demand and growth scenarios. The third area assesses the physical requirements of substituting coal demand growth with other primary energy forms. Finally, the study examines the carbon- and environmental implications of China's past and future coal consumption. There are three sections that address these areas by identifying particular characteristics of China's coal industry, quantifying factors driving demand, and analyzing supply scenarios: (1) reviews the range of Chinese and international estimates of remaining coal reserves and resources as well as key characteristics of China's coal industry including historical production, resource requirements, and prices; (2) quantifies the largest drivers of coal usage to produce a bottom-up reference projection of 2025 coal demand; and (3) analyzes coal supply constraints, substitution options, and environmental externalities. Finally, the last section presents conclusions on the role of coal in China's ongoing energy and economic development. China has been, is, and will continue to be a coal-powered economy. In 2007 Chinese coal production contained more energy than total Middle Eastern oil production. The rapid growth of coal demand after 2001 created supply strains and bottlenecks that raise questions about sustainability. Urbanization, heavy industrial growth, and increasing per-capita income are the primary interrelated drivers of rising coal usage. In 2007, the power sector, iron and steel, and cement production accounted for 66% of coal consumption. Power generation is becoming more efficient, but even extensive roll-out of the highest efficiency units would save only 14% of projected 2025 coal demand for the power sector. A new wedge of

  17. MIKROMITSETY- MIGRANTS IN MINGECHEVIR RESERVOIR

    Directory of Open Access Journals (Sweden)

    M. A. Salmanov

    2017-01-01

    Full Text Available Aim. It is hardly possible to predict the continued stability of the watercourse ecosystems without the study of biological characteristics and composition of organisms inhabiting them. In the last 35-40 years, environmental conditions of the Mingachevir reservoir are determined by the stationary anthropogenic pressure. It was found that such components of plankton as algae, bacteria and fungi play a leading role in the transformation and migration of pollutants. The role of the three groups of organisms is very important in maintaining the water quality by elimination of pollutants. Among the organisms inhabiting the Mingachevir Reservoir, micromycetes have not yet been studied. Therefore, the study of the species composition and seasonal dynamics, peculiarities of their growth and development in the environment with the presence of some of the pollutants should be considered to date.Methods. In order to determine the role of micromycetes-migrants in the mineralization of organic substrates, as an active participant of self-purification process, we used water samples from the bottom sediments as well as decaying and skeletonized stalks of cane, reeds, algae, macrophytes, exuvia of insects and fish remains submerged in water.Findings. For the first time, we obtained the data on the quality and quantity of microscopic mycelial fungi in freshwater bodies on the example of the Mingachevir water reservoir; we also studied the possibilities for oxygenating the autochthonous organic matter of allochthonous origin with micromycetes-migrants.Conclusions. It was found that the seasonal development of micromycetes-migrants within the Mingachevir reservoir is characterized by an increase in the number of species in the summer and a gradual reduction in species diversity in the fall. 

  18. [Research progress on phosphorus budgets and regulations in reservoirs].

    Science.gov (United States)

    Shen, Xiao; Li, Xu; Zhang, Wang-shou

    2014-12-01

    Phosphorus is an important limiting factor of water eutrophication. A clear understanding of its budget and regulated method is fundamental for reservoir ecological health. In order to pro- mote systematic research further and improve phosphorus regulation system, the budget balance of reservoir phosphorus and its influencing factors were concluded, as well as conventional regulation and control measures. In general, the main phosphorus sources of reservoirs include upstream input, overland runoff, industrial and domestic wastewater, aquaculture, atmospheric deposition and sediment release. Upstream input is the largest phosphorus source among them. The principal output path of phosphorus is the flood discharge, the emission load of which is mainly influenced by drainage patterns. In addition, biological harvest also can export a fraction of phosphorus. There are some factors affecting the reservoir phosphorus balance, including reservoirs' function, hydrological conditions, physical and chemical properties of water, etc. Therefore, the phosphorus budgets of different reservoirs vary greatly, according to different seasons and regions. In order to reduce the phosphorus loading in reservoirs, some methods are carried out, including constructed wetlands, prefix reservoir, sediment dredging, biomanipulation, etc. Different methods need to be chosen and combined according to different reservoirs' characteristics and water quality management goals. Thus, in the future research, it is reasonable to highlight reservoir ecological characteristics and proceed to a complete and systematic analysis of the inherent complexity of phosphorus budget and its impact factors for the reservoirs' management. Besides, the interaction between phosphorus budget and other nutrients in reservoirs also needs to be conducted. It is fundamental to reduce the reservoirs' phosphorus loading to establish a scientific and improved management system based on those researches.

  19. Japan`s sunshine project. 17.. 1992 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    This report describes the achievement of coal liquefaction and gasification technology development in the Sunshine Project for FY 1992. It presents the research and development of coal liquefaction which includes studies on reaction mechanism of coal liquefaction and catalysts for coal liquefaction, the research and development of coal gasification technologies which includes studies on gasification characteristics of various coals and improvement of coal gasification efficiency, the development of bituminous coal liquefaction which includes engineering, construction and operation of a bituminous coal liquefaction pilot plant and research by a process supporting unit (PSU), the development of brown coal liquefaction which includes research on brown coal liquefaction with a pilot plant and development of techniques for upgrading coal oil from brown coal, the development of common base technologies which includes development of slurry letdown valves and study on upgrading technology of coal-derived distillates, the development of coal-based hydrogen production technology with a pilot plant, the development of technology for entrained flow coal gasification, the assessment of coal hydrogasification, and the international co-operation. 4 refs., 125 figs., 39 tabs.

  20. Combined compressed air storage-low BTU coal gasification power plant

    Science.gov (United States)

    Kartsounes, George T.; Sather, Norman F.

    1979-01-01

    An electrical generating power plant includes a Compressed Air Energy Storage System (CAES) fueled with low BTU coal gas generated in a continuously operating high pressure coal gasifier system. This system is used in coordination with a continuously operating main power generating plant to store excess power generated during off-peak hours from the power generating plant, and to return the stored energy as peak power to the power generating plant when needed. The excess coal gas which is produced by the coal gasifier during off-peak hours is stored in a coal gas reservoir. During peak hours the stored coal gas is combined with the output of the coal gasifier to fuel the gas turbines and ultimately supply electrical power to the base power plant.

  1. The pollution of the 'iron gate' reservoir

    International Nuclear Information System (INIS)

    Babic-Mladenovic, M.; Varga, S; Popovic, L.; Damjanovic, M.

    2002-01-01

    The paper presents the characteristics of the Iron Gate I (the Djerdap) Water Power and Navigational System, one of the largest in Europe (completed in 1972 by joint efforts of Yugoslavia and Romania). In this paper the attention is devoted to review of the sediment monitoring program and impacts of reservoir sedimentation, as well as to the investigations of water and sediment quality. Special consideration is paid to the issue of sediment pollution research needs. Namely, the hot spot of the 'Iron Gate' sedimentation represents a scarcely known pollution of sediment deposits. The present pollution probably is considerable, since the 'Iron Gate' reservoir drains about 577000 km 2 , with over 80 million inhabitants, and developed municipal and industrial infrastructure. Therefore, in the thirty-year reservoir life various types of sediment-bound pollutants entered and deposited within it. Especially severe incidents happened during 1999 (as a result of NATO bombing campaign) and 2000 (two accidental pollutions in the Tisza river catchment). The study of the 'Iron Gate' reservoir pollution should be prepared in order to enlighten the present state of reservoir sedimentation and pollution. The main objectives of the study are to enhance the government and public awareness of the present environmental state of the 'Iron Gate' reservoir and to serve as a baseline for all future actions. (author)

  2. Trends in Japanese coal trade

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, S

    1986-01-01

    The author discusses 1) the latest forecast for coal demand in Japan; 2) trends in Japanese steam coal demand, with breakdown by industry; 3) the organization of steam coal supply, with details of the distribution network and of the new coal cartridge system; 4) the demand for metallurgical coal. Other topics outlined include the current status of Japanese coal production, Japanese coal trade, and the development of overseas coal resources. 1 figure, 5 tables.

  3. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1995-02-01

    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

  4. Biochemically enhanced methane production from coal

    Science.gov (United States)

    Opara, Aleksandra

    For many years, biogas was connected mostly with the organic matter decomposition in shallow sediments (e.g., wetlands, landfill gas, etc.). Recently, it has been realized that biogenic methane production is ongoing in many hydrocarbon reservoirs. This research examined microbial methane and carbon dioxide generation from coal. As original contributions methane production from various coal materials was examined in classical and electro-biochemical bench-scale reactors using unique, developed facultative microbial consortia that generate methane under anaerobic conditions. Facultative methanogenic populations are important as all known methanogens are strict anaerobes and their application outside laboratory would be problematic. Additional testing examined the influence of environmental conditions, such as pH, salinity, and nutrient amendments on methane and carbon dioxide generation. In 44-day ex-situ bench-scale batch bioreactor tests, up to 300,000 and 250,000 ppm methane was generated from bituminous coal and bituminous coal waste respectively, a significant improvement over 20-40 ppm methane generated from control samples. Chemical degradation of complex hydrocarbons using environmentally benign reagents, prior to microbial biodegradation and methanogenesis, resulted in dissolution of up to 5% bituminous coal and bituminous coal waste and up to 25% lignite in samples tested. Research results confirm that coal waste may be a significant underutilized resource that could be converted to useful fuel. Rapid acidification of lignite samples resulted in low pH (below 4.0), regardless of chemical pretreatment applied, and did not generate significant methane amounts. These results confirmed the importance of monitoring and adjusting in situ and ex situ environmental conditions during methane production. A patented Electro-Biochemical Reactor technology was used to supply electrons and electron acceptor environments, but appeared to influence methane generation in a

  5. Report on the achievements in the Sunshine Project in investigations and studies on treatment technologies for coals used in coal gasification. A report on coal type investigation; Sekitan gas ka yotan no shori gijutsu ni kansuru chosa kenkyu. Tanshu chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-03-01

    This paper reports the investigation on coal types for coal gasification in the Sunshine Project. With regard to the status of existence, production and dressing of coals as the material for coal gasification and liquefaction, summarized site investigations and sampling were performed on underground mining coal mines being operated in Japan. Test sample coals are put into a data file as the important fundamental data for gasification and liquefaction characteristics tests at the Japan Coal Energy Center. The sampling investigation is planned to start in fiscal 1988. The coal mines having been investigated to date include: Taiheiyo Coal Mine (Kushiro), Mitsui Coal Mining Industry (Miike), Matsushima Coal Mine (Ikejima), Mitsubishi Coal Mining Industry (Minami O-Yubari), Sumitomo Coal Akabira Coal Mine (Akabira), Mitsui Coal Mining Industry (Ashibetsu), and Sorachi Coal Mine (Sorachi). Coal beds subjected to the sampling were selected upon carefully discussing with the site engineers on the current status of the coal mine, and the coal beds that could be operated in the future. The sampling method was such that the whole coal bed from the upper bed to the lower bed at the facing was sampled and put into vinyl sampling bags each at about 2 kg as the target. (NEDO)

  6. Characterization and 3D reservoir modelling of fluvial sandstones of the Williams Fork Formation, Rulison Field, Piceance Basin, Colorado, USA

    International Nuclear Information System (INIS)

    Pranter, Matthew J; Vargas, Marielis F; Davis, Thomas L

    2008-01-01

    This study describes the stratigraphic characteristics and distribution of fluvial deposits of the Upper Cretaceous Williams Fork Formation in a portion of Rulison Field and addresses 3D geologic modelling of reservoir sand bodies and their associated connectivity. Fluvial deposits include isolated and stacked point-bar deposits, crevasse splays and overbank (floodplain) mudrock. Within the Williams Fork Formation, the distribution and connectivity of fluvial sandstones significantly impact reservoir productivity and ultimate recovery. The reservoir sandstones are primarily fluvial point-bar deposits interbedded with shales and coals. Because of the lenticular geometry and limited lateral extent of the reservoir sandstones (common apparent widths of ∼500–1000 ft; ∼150–300 m), relatively high well densities (e.g. 10 acre (660 ft; 200 m) spacing) are often required to deplete the reservoir. Heterogeneity of these fluvial deposits includes larger scale stratigraphic variability associated with vertical stacking patterns and structural heterogeneities associated with faults that exhibit lateral and reverse offsets. The discontinuous character of the fluvial sandstones and lack of distinct marker beds in the middle and upper parts of the Williams Fork Formation make correlation between wells tenuous, even at a 10 acre well spacing. Some intervals of thicker and amalgamated sandstones within the middle and upper Williams Fork Formation can be correlated across greater distances. To aid correlation and for 3D reservoir modelling, vertical lithology proportion curves were used to estimate stratigraphic trends and define the stratigraphic zonation within the reservoir interval. Object-based and indicator-based modelling methods have been applied to the same data and results from the models were compared. Results from the 3D modelling indicate that sandstone connectivity increases with net-to-gross ratio and, at lower net-to-gross ratios (<30%), differences exist in

  7. Natural radioactivity level in coal and ash collected from Baoji coal-fired power plant

    International Nuclear Information System (INIS)

    Jia Xiaodan; Lu Xinwei

    2006-01-01

    Specific activities of natural radionuclides 226 Ra, 232 Th and 40 K were assessed in coal (3 samples), fly ash (17 samples) and bottom ash (6 samples) collected from Baoji coal-fired power plant. This paper analyzed the characteristics of 226 Ra, 232 Th and 40 K contents in bottom ash and fly ash, and studied the concentration factors of these radionuclides in ash in relation to those in coal. The level of natural radionuclides 226 Ra, 232 Th and 40 K of coal collected from Baoji coal-fired power plant are in the range of radionuclides contents of Chinese coal. The natural radioactivity level of fly ash collected from Baoji coal-fired power plant is close to Beijing and Shanghai coal-fired power plants. The paper farther assessed the possibility of fly ash of Baoji coal-fired power plant used as building materials according to the state standard. The results show that there are 29% samples exceeding the state limit when fly ash used as building materials. So the usage of fly ash in building material should be controlled. (authors)

  8. Report on the achievements in the Sunshine Project in fiscal 1993 on development of a jet flow bed gasification electric power plant. Investigative research on a technology to treat coals used for coal gasification (investigation for coal type selection); 1993 nendo funryusho gas ka hatsuden plant kaihatsu seika hokokusho. Sekitan gas kayotan no shori gijutsu ni kansuru chosa kenkyu (tanshu sentei chosa)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1984-03-01

    This paper describes the achievements in the Sunshine Project in fiscal 1993 in the investigation for coal type selection. The investigation is purposed to elucidate the status of existence and resources of coals as the raw material for coal gasification and liquefaction, the coal quality features, and the gasification and liquefaction characteristics. The results will be used as the fundamental materials for technological development. Discussions will also be given on the coal applicability to the composite gasification power generation system in which liquefied residue generated in the process are mixed with the supplied coal. Coal quality analysis and a liquefaction test under the standard condition were completed on 389 test samples composed of 136 kinds of coals produced in Canada, Australia, the U.S.A., China and Indonesia. Coal types were enumerated according to the oil yield. A gasification test was performed on the specific gravity separated coals of Chinese coals to discuss the effect of change in the ash amount on the gasification characteristics. A partial coal combustion test revealed that fuel ratio, oxygen partial pressure, and oxygen molar fraction parameters affect the combustion characteristics. The micro-gravity field is effective in discussing the combustion characteristics of particulate groups of dust coal. A coal oxidizing test was performed, wherein oxidizing characteristics and spontaneous ignition performance were estimated successfully from temperature rise of heat stored in coal. The coal type matrix data were prepared. (NEDO)

  9. Nitrogen in Chinese coals

    Science.gov (United States)

    Wu, D.; Lei, J.; Zheng, B.; Tang, X.; Wang, M.; Hu, Jiawen; Li, S.; Wang, B.; Finkelman, R.B.

    2011-01-01

    Three hundred and six coal samples were taken from main coal mines of twenty-six provinces, autonomous regions, and municipalities in China, according to the resource distribution and coal-forming periods as well as the coal ranks and coal yields. Nitrogen was determined by using the Kjeldahl method at U. S. Geological Survey (USGS), which exhibit a normal frequency distribution. The nitrogen contents of over 90% Chinese coal vary from 0.52% to 1.41% and the average nitrogen content is recommended to be 0.98%. Nitrogen in coal exists primarily in organic form. There is a slight positive relationship between nitrogen content and coal ranking. ?? 2011 Science Press, Institute of Geochemistry, CAS and Springer Berlin Heidelberg.

  10. Coal marketing manual 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    This manual presents information for the use of marketers, consumers, analysts and investors. The information is presented in a series of tables and figures. Statistics are given for: Australian export tonnages and average export values for 1978-1985; international pig iron production 1976 to 1985; and international crude steel production 1979 to 1985. Trends in Australian export tonnages and prices of coal are reviewed. Details of international loading and discharge ports are given, together with a historical summary of shipping freight-rates since 1982. Long term contract prices for thermal and coking coal to Japan are tabulated. A review of coal and standards is given, together with Australian standards for coal and coke. A section on coal quality is included containing information on consumer coal quality preferences and Australian and Overseas coal brands and qualities. Finally an index is given of contact details of Australian and Overseas exporting companies, government departments, and the Australian Coal Association.

  11. Coal worker's pneumoconiosis

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000130.htm Coal worker's pneumoconiosis To use the sharing features on this page, please enable JavaScript. Coal worker's pneumoconiosis (CWP) is a lung disease that ...

  12. Historical deposition and fluxes of mercury in Narraguinnep Reservoir, southwestern Colorado, USA

    International Nuclear Information System (INIS)

    Gray, John E.; Fey, David L.; Holmes, Charles W.; Lasorsa, Brenda K.

    2005-01-01

    Narraguinnep Reservoir has been identified as containing fish with elevated Hg concentrations and has been posted with an advisory recommending against consumption of fish. There are presently no point sources of significant Hg contamination to this reservoir or its supply waters. To evaluate potential historical Hg sources and deposition of Hg to Narraguinnep Reservoir, the authors measured Hg concentrations in sediment cores collected from this reservoir. The cores were dated by the 137 Cs method and these dates were further refined by relating water supply basin hydrological records with core sedimentology. Rates of historical Hg flux were calculated (ng/cm 2 /a) based on the Hg concentrations in the cores, sediment bulk densities, and sedimentation rates. The flux of Hg found in Narraguinnep Reservoir increased by approximately a factor of 2 after about 1970. The 3 most likely sources of Hg to Narraguinnep Reservoir are surrounding bedrocks, upstream inactive Au-Ag mines, and several coal-fired electric power plants in the Four Corners region. Patterns of Hg flux do not support dominant Hg derivation from surrounding bedrocks or upstream mining sources. There are 14 coal-fired power plants within 320 km of Narraguinnep Reservoir that produce over 80 x 10 6 MWH of power and about 1640 kg-Hg/a are released through stack emissions, contributing significant Hg to the surrounding environment. Two of the largest power plants, located within 80 km of the reservoir, emit about 950 kg-Hg/a. Spatial and temporal patterns of Hg fluxes for sediment cores collected from Narraguinnep Reservoir suggest that the most likely source of Hg to this reservoir is from atmospheric emissions from the coal-fired electric power plants, the largest of which began operation in this region in the late-1960s and early 1970s

  13. Hydromechanical and Thermomechanical Behaviour of Elastic Fractures during Thermal Stimulation of Naturally Fractured Reservoirs

    Science.gov (United States)

    Jalali, Mohammadreza; Valley, Benoît

    2015-04-01

    During the last two decades, incentives were put in place in order to feed our societies in energy with reduced CO2 emissions. Various policies have been considered to fulfill this strategy such as replacing coal by natural gas in power plants, producing electricity using CO2 free resources, and CO2 sequestration as a remediation for large point-source emitters (e.g. oil sands facilities, coal-fired power plants, and cement kilns). Naturally fractured reservoirs (NFRs) are among those geological structures which play a crucial role in the mentioned energy revolution. The behavior of fractured reservoirs during production processes is completely different than conventional reservoirs because of the dominant effects of fractures on fluid flux, with attendant issues of fracture fabric complexity and lithological heterogeneity. The level of complexity increases when thermal effects are taking place - as during the thermal stimulation of these stress-sensitive reservoirs in order to enhance the gas production in tight shales and/or increase the local conductivity of the fractures during the development of enhanced geothermal systems - where temperature is introduced as another degree of freedom in addition to pressure and displacement (or effective stress). Study of these stress-pressure-temperature effects requires a thermo-hydro-mechanical (THM) coupling approach, which considers the simultaneous variation of effective stress, pore pressure, and temperature and their interactions. In this study, thermal, hydraulic and mechanical behavior of partially open and elastic fractures in a homogeneous, isotropic and low permeable porous rock is studied. In order to compare the hydromechanical (HM) and thermomechanical (TM) characteristics of these fractures, three different injection scenarios, i.e. constant isothermal fluid injection rate, constant cooling without any fluid injection and constant cold fluid injection, are considered. Both thermomechanical and hydromechanical

  14. The upper pennsylvanian pittsburgh coal bed: Resources and mine models

    Science.gov (United States)

    Watson, W.D.; Ruppert, L.F.; Tewalt, S.J.; Bragg, L.J.

    2001-01-01

    The U.S. Geological Survey recently completed a digital coal resource assessment model of the Upper Pennsylvanian Pittsburgh coal bed, which indicates that after subtracting minedout coal, 16 billion short tons (14 billion tonnes) remain of the original 34 billion short tons (31 billion tonnes) of coal. When technical, environmental, and social restrictions are applied to the remaining Pittsburgh coal model, only 12 billion short tons (11 billion tonnes) are available for mining. Our assessment models estimate that up to 0.61 billion short tons (0.55 billion tonnes), 2.7 billion short tons (2.4 billion tonnes), and 8.5 billion short tons (7.7 billion tonnes) could be available for surface mining, continuous mining, and longwall mining, respectively. This analysis is an example of a second-generation regional coal availability study designed to model recoverability characteristics for all the major coal beds in the United States. ?? 2001 International Association for Mathematical Geology.

  15. Fording Canadian Coal Trust

    Energy Technology Data Exchange (ETDEWEB)

    Popowich, J.; Millos, R. [Elk Valley Coal Corporation, Calgary, AB (Canada)

    2004-07-01

    This is the first of five slide/overhead presentations presented at the Fording Canadian Coal Trust and Tech Cominco Ltd. investor day and mine tour. The Fording Canadian Coal Trust is described. The Trust's assets comprise six Elk Valley metallurgical coal mines and six wollastonite operations (in the NYCO Group). Trust structure, corporate responsibility, organizational structure, reserves and resources, management philosophy, operating strategies, steel market dynamics, coal market, production expansion, sales and distribution are outlined. 15 figs., 5 tabs.

  16. Coal. [1987 and 1989

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    Despite increases in recently negotiated coal prices in US dollar terms, unit export returns for Australian coal are expected to rise only marginally in 1988-89 due to the anticipated appreciation of the Australian dollar. Australian coal production is expected to recover in 1988-89, after falling in 1987-88. A table summarising coal statistics in 1985-87 is presented. 2 figs., 1 tab.

  17. Review biodepyritisation of coal

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, C.; Sukla, L.B.; Misra, V.N. [Regional Research Lab., Orissa (India)

    2004-01-01

    This review provides a detailed summary of the recent and past research activities in the area of biodesulfurisation of coal. It provides information about microorganisms important for biodesulfurisation of coal, with the emphasis on Thiobacillus ferrooxidans. The review presents an insight into various methods of desulfurisation of coal combining physical and biological methods. Also, there are discussions on coal structure, distribution, mechanism and kinetics of pyrite oxidation and jarosite precipitation. Finally, areas requiring further research are identified.

  18. Coal dust symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    This paper gives a report of the paper presented at the symposium held in Hanover on 9 and 10 February 1981. The topics include: the behaviour of dust and coal dust on combustion and explosion; a report on the accidents which occurred at the Laegerdorf cement works' coal crushing and drying plant; current safety requirements at coal crushing and drying plant; and coal crushing and drying. Four papers are individually abstracted. (In German)

  19. Coal world market

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    A brief analysis of major tendencies in the world market of coal is presented. It is pointed out that recent years, by and large, were favourable for the development of the world coal industry. Prices for coal (both for power-grade and coking one) in 1995 after many years of depressive state increased by nearly 20 % and reached a maximum of the last decade. International coal trading continues to grow and the tendency may persist in the mext two years

  20. Inorganic Constituents in Coal

    Directory of Open Access Journals (Sweden)

    Rađenović A.

    2006-02-01

    Full Text Available Coal contains not only organic matter but also small amounts of inorganic constituents. More thanone hundred different minerals and virtually every element in the periodic table have been foundin coal. Commonly found group minerals in coal are: major (quartz, pyrite, clays and carbonates,minor, and trace minerals. Coal includes a lot of elements of low mass fraction of the orderof w=0.01 or 0.001 %. They are trace elements connected with organic matter or minerals comprisedin coal. The fractions of trace elements usually decrease when the rank of coal increases.Fractions of the inorganic elements are different, depending on the coal bed and basin. A varietyof analytical methods and techniques can be used to determine the mass fractions, mode ofoccurrence, and distribution of organic constituents in coal. There are many different instrumentalmethods for analysis of coal and coal products but atomic absorption spectroscopy – AAS is theone most commonly used. Fraction and mode of occurrence are one of the main factors that haveinfluence on transformation and separation of inorganic constituents during coal conversion.Coal, as an important world energy source and component for non-fuels usage, will be continuouslyand widely used in the future due to its relatively abundant reserves. However, there is aconflict between the requirements for increased use of coal on the one hand and less pollution onthe other. It’s known that the environmental impacts, due to either coal mining or coal usage, canbe: air, water and land pollution. Although, minor components, inorganic constituents can exert asignificant influence on the economic value, utilization, and environmental impact of the coal.

  1. REGULATION OF COAL POLYMER DEGRADATION BY FUNGI

    Energy Technology Data Exchange (ETDEWEB)

    John A. Bumpus

    1998-11-30

    A variety of lignin degrading fungi mediate solubilization and subsequent biodegradation of coal macromolecules (a.k.a. coal polymer) from highly oxidized low rank coals such as leonardites. It appears that oxalate or possibly other metal chelators (i.e., certain Krebs Cycle intermediates) mediate solubilization of low rank coals while extracellular oxidases have a role in subsequent oxidation of solubilized coal macromolecule. These processes are under nutritional control. For example, in the case of P. chrysosporium, solubilization of leonardite occurred when the fungi were cultured on most but not all nutrient agars tested and subsequent biodegradation occurred only in nutrient nitrogen limited cultures. Lignin peroxidases mediate oxidation of coal macromolecule in a reaction that is dependent on the presence of veratryl alcohol and hydrogen peroxide. Kinetic evidence suggests that veratryl alcohol is oxidized to the veratryl alcohol cation radical which then mediates oxidation of the coal macromolecule. Results by others suggest that Mn peroxidases mediate formation of reactive Mn{sup 3+} complexes which also mediate oxidation of coal macromolecule. A biomimetic approach was used to study solubilization of a North Dakota leonardite. It was found that a concentration {approximately}75 mM sodium oxalate was optimal for solubilization of this low rank coal. This is important because this is well above the concentration of oxalate produced by fungi in liquid culture. Higher local concentrations probably occur in solid agar cultures and thus may account for the observation that greater solubilization occurs in agar media relative to liquid media. The characteristics of biomimetically solubilized leonardite were similar to those of biologically solubilized leonardite. Perhaps our most interesting observation was that in addition to oxalate, other common Lewis bases (phosphate/hydrogen phosphate/dihydrogen phosphate and bicarbonate/carbonate ions) are able to mediate

  2. Emission characteristics for gaseous- and size-segregated particulate PAHs in coal combustion flue gas from circulating fluidized bed (CFB) boiler.

    Science.gov (United States)

    Wang, Ruwei; Liu, Guijian; Sun, Ruoyu; Yousaf, Balal; Wang, Jizhong; Liu, Rongqiong; Zhang, Hong

    2018-07-01

    The partitioning behavior of polycyclic aromatic hydrocarbons (PAHs) between gaseous and particulate phases from coal-fired power plants (CFPPs) is critically important to predict PAH removal by dust control devices. In this study, 16 US-EPA priority PAHs in gaseous and size-segregated particulate phases at the inlet and outlet of the fabric filter unit (FFs) of a circulating fluidized bed (CFB) boiler were analyzed. The partitioning mechanisms of PAHs between gaseous and particulate phases and in particles of different size classes were investigated. We found that the removal efficiencies of PAHs are 45.59% and 70.67-89.06% for gaseous and particulate phases, respectively. The gaseous phase mainly contains low molecular weight (LMW) PAHs (2- and 3-ring PAHs), which is quite different from the particulate phase that mainly contains medium and high molecular weight (MMW and HMW) PAHs (4- to 6-ring PAHs). The fractions of LMW PAHs show a declining trend with the decrease of particle size. The gas-particle partitioning of PAHs is primarily controlled by organic carbon absorption, in addition, it has a clear dependence on the particle sizes. Plot of log (TPAH/PM) against logD p shows that all slope values were below -1, suggesting that PAHs were mainly adsorbed to particulates. The adsorption effect of PAHs in size-segregated PMs for HMW PAHs is more evident than LMW PAHs. The particle size distributions (PSDs) of individual PAHs show that most of PAHs exhibit bi-model structures, with one mode peaking in the accumulation size range (2.1-1.1 μm) and another mode peaking in coarse size range (5.8-4.7 μm). The intensities of these two peaks vary in function of ring number of PAHs, which is likely attributed to Kelvin effect that the less volatile HMW PAH species preferentially condense onto the finer particulates. The emission factor of PAHs was calculated as 3.53 mg/kg of coal burned, with overall mean EF PAH of 0.55 and 2.98 mg/kg for gaseous and particulate

  3. Automated mineralogical logging of coal and coal measure core

    Energy Technology Data Exchange (ETDEWEB)

    Stephen Fraser; Joan Esterle; Colin Ward; Ruth Henwood; Peter Mason; Jon Huntington; Phil Connor; Reneta Sliwa; Dave Coward; Lew Whitbourn [CSIRO Exploration & Mining (Australia)

    2006-06-15

    A mineralogical core logging system based on spectral reflectance (HyLogger{trademark}) has been used to detect and quantify mineralogies in coal and coal measure sediments. The HyLogger{trademark} system, as tested, operates in the visible-to-shortwave infrared spectral region, where iron oxides, sulphates, hydroxyl-bearing and carbonate minerals have characteristic spectral responses. Specialized software assists with mineral identification and data display. Three Phases of activity were undertaken. In Phase I, carbonates (siderite, ankerite, calcite) and clays (halloysite, dickite) were successfully detected and mapped in coal. Repeat measurements taken from one of the cores after three months demonstrated the reproducibility of the spectral approach, with some spectral differences being attributed to variations in moisture content and oxidation. Also, investigated was HyLogger{trademark} ability to create a 'brightness-profile' on coal materials, and these results were encouraging. In Phase II, geotechnically significant smectitic clays (montmorillonite) were detected and mapped in cores of clastic roof and floor materials. Such knowledge would be useful for mine planning and design purposes. In Phase III, our attempts at determining whether phosphorus-bearing minerals such as apatite could be spectrally detected were less than conclusive. A spectral index could only be created for apatite, and the relationships between the spectrally-derived apatite-index, the XRD results and the analytically-derived phosphorus measurements were ambiguous.

  4. Hydrogeochemistry and coal-associated bacterial populations from a methanogenic coal bed

    Science.gov (United States)

    Barnhart, Elliott P.; Weeks, Edwin P.; Jones, Elizabeth J.P.; Ritter, Daniel J.; McIntosh, Jennifer C.; Clark, Arthur C.; Ruppert, Leslie F.; Cunningham, Alfred B.; Vinson, David S.; Orem, William H.; Fields, Matthew W.

    2016-01-01

    Biogenic coalbed methane (CBM), a microbially-generated source of natural gas trapped within coal beds, is an important energy resource in many countries. Specific bacterial populations and enzymes involved in coal degradation, the potential rate-limiting step of CBM formation, are relatively unknown. The U.S. Geological Survey (USGS) has established a field site, (Birney test site), in an undeveloped area of the Powder River Basin (PRB), with four wells completed in the Flowers-Goodale coal bed, one in the overlying sandstone formation, and four in overlying and underlying coal beds (Knoblach, Nance, and Terret). The nine wells were positioned to characterize the hydraulic conductivity of the Flowers-Goodale coal bed and were selectively cored to investigate the hydrogeochemistry and microbiology associated with CBM production at the Birney test site. Aquifer-test results indicated the Flowers-Goodale coal bed, in a zone from about 112 to 120 m below land surface at the test site, had very low hydraulic conductivity (0.005 m/d) compared to other PRB coal beds examined. Consistent with microbial methanogenesis, groundwater in the coal bed and overlying sandstone contain dissolved methane (46 mg/L average) with low δ13C values (−67‰ average), high alkalinity values (22 meq/kg average), relatively positive δ13C-DIC values (4‰ average), and no detectable higher chain hydrocarbons, NO3−, or SO42−. Bioassay methane production was greatest at the upper interface of the Flowers-Goodale coal bed near the overlying sandstone. Pyrotag analysis identified Aeribacillus as a dominant in situbacterial community member in the coal near the sandstone and statistical analysis indicated Actinobacteria predominated coal core samples compared to claystone or sandstone cores. These bacteria, which previously have been correlated with hydrocarbon-containing environments such as oil reservoirs, have demonstrated the ability to produce biosurfactants to break down

  5. Hard coal; Steinkohle

    Energy Technology Data Exchange (ETDEWEB)

    Loo, Kai van de; Sitte, Andreas-Peter [Gesamtverband Steinkohle e.V., Herne (Germany)

    2013-04-01

    The year 2012 benefited from a growth of the consumption of hard coal at the national level as well as at the international level. Worldwide, the hard coal still is the number one energy source for power generation. This leads to an increasing demand for power plant coal. In this year, the conversion of hard coal into electricity also increases in this year. In contrast to this, the demand for coking coal as well as for coke of the steel industry is still declining depending on the market conditions. The enhanced utilization of coal for the domestic power generation is due to the reduction of the nuclear power from a relatively bad year for wind power as well as reduced import prices and low CO{sub 2} prices. Both justify a significant price advantage for coal in comparison to the utilisation of natural gas in power plants. This was mainly due to the price erosion of the inexpensive US coal which partly was replaced by the expansion of shale gas on the domestic market. As a result of this, the inexpensive US coal looked for an outlet for sales in Europe. The domestic hard coal has continued the process of adaptation and phase-out as scheduled. Two further hard coal mines were decommissioned in the year 2012. RAG Aktiengesellschaft (Herne, Federal Republic of Germany) running the hard coal mining in this country begins with the preparations for the activities after the time of mining.

  6. Coal economics and taxation

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    These proceedings contain opening remarks, the luncheon and dinner addresses, list of delegates and the papers presented at the four sessions on Coal Mines cost money - for what.; Coal mines cost money - Where the money comes from; taxation and royalty policies; and the coal industry view on operating costs. Sixteen papers are abstracted separately.

  7. Functional age as an indicator of reservoir senescence

    Science.gov (United States)

    Miranda, Leandro E.; Krogman, R. M.

    2015-01-01

    It has been conjectured that reservoirs differ in the rate at which they manifest senescence, but no attempt has been made to find an indicator of senescence that performs better than chronological age. We assembled an indicator of functional age by creating a multimetric scale consisting of 10 metrics descriptive of reservoir environments that were expected to change directionally with reservoir senescence. In a sample of 1,022 U.S. reservoirs, chronological age was not correlated with functional age. Functional age was directly related to percentage of cultivated land in the catchment and inversely related to reservoir depth. Moreover, aspects of reservoir fishing quality and fish population characteristics were related to functional age. A multimetric scale to indicate reservoir functional age presents the possibility for management intervention from multiple angles. If a reservoir is functionally aging at an accelerated rate, action may be taken to remedy the conditions contributing most to functional age. Intervention to reduce scores of selected metrics in the scale can potentially reduce the rate of senescence and increase the life expectancy of the reservoir. This leads to the intriguing implication that steps can be taken to reduce functional age and actually make the reservoir grow younger.

  8. DEVELOPMENT OF RESERVOIR CHARACTERIZATION TECHNIQUES AND PRODUCTION MODELS FOR EXPLOITING NATURALLY FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes

    2002-12-31

    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for

  9. Characteristic analysis of methane-gas generation by oxidizing heat of stored coal and hold ventilation control; Sekitan unpansen ni okeru sanka hatsunetsu ni yoru methane gas hassei to sonai kankyo seigyo ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Fukuchi, N; Nakashima, T [Kyushu Univ., Fukuoka (Japan); Kudo, S

    1999-12-31

    A demand of coal shows the tendency in the increase worldwide, with this, the marine transportation of the coal gradually increases, and the collier has also enlarged. The traffic pattern of coal is mainly the bulk transportation. In this transportation system, by the oxidation exothermic reaction of the coal, methane gas is produced, simultaneously the coal quality such as coking property or heat quantity is decreased and sometimes spontaneous ignition is caused. Therefore, it is necessary to equip with a ventilator to control the concentration of methane gas and to avoid the self heating of the coal. In this study, the quantity of methane-gas produced by heating coal using an electric furnace was measured and the experiment to investigate the temperature dependency of the methane-gas generated from the coal was conducted. By using the result of the measurement, the quantity of methane-gas produced from the coal stored in the hold of a coal cargo was estimated. And, the mathematical analyses on the changing degree depend on the times of a temperature in the hold under navigation, a concentration of oxygen and a concentration of methane-gas, were conducted. 11 refs., 19 figs., 2 tabs.

  10. Land use and coal technology

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The Arid Lands Ecology Reserve and the Hanford National Environmental Research Park were established to promote the use of the Hanford Site for ecological research, especially studies related to energy technologies and their potential for environmental impacts. Coal is currently regarded as the most dependable interim source of energy in the United States. To meet expected demands, coal needs to be mined in large quantities and may be mined predominantly in locations of sparse precipitation. Often the most economical way to extract coal is through surface mining. It is expected that following coal extraction the pits will be filled with overburden, graded to approximate original contour, native topsoil applied to prescribed depths and planted with climatically adapted herbs, shrubs or trees. Because primary productivity in dry regions is characteristically low, it is realistic to expect, if the above procedure is followed, that the revegetated surfaces will also produce little phytomass in the years following restoration. Appropriate data are needed for accurate estimation of the economic feasibility of a particular restoration practice or its alternative. Research programs are discussed briefly

  11. Management of coal combustion wastes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-02-01

    It has been estimated that 780 Mt of coal combustion products (CCPs) were produced worldwide in 2010. Only about 53.5% were utilised, the rest went to storage or disposal sites. Disposal of coal combustion waste (CCW) on-site at a power plant may involve decades-long accumulation of waste, with hundreds of thousands, if not millions, of tonnes of dry ash or wet ash slurry being stored. In December 2008, a coal combustion waste pond in Kingston, Tennessee, USA burst. Over 4 million cubic metres of ash sludge poured out, burying houses and rivers in tonnes of toxic waste. Clean-up is expected to continue into 2014 and will cost $1.2 billion. The incident drew worldwide attention to the risk of CCW disposal. This caused a number of countries to review CCW management methods and regulations. The report begins by outlining the physical and chemical characteristics of the different type of ashes generated in a coal-fired power plant. The amounts of CCPs produced and regulations on CCW management in selected countries have been compiled. The CCW disposal methods are then discussed. Finally, the potential environmental impacts and human health risks of CCW disposal, together with the methods used to prevent them, are reviewed.

  12. Australian Coal Company Risk Factors: Coal and Oil Prices

    OpenAIRE

    M. Zahid Hasan; Ronald A. Ratti

    2014-01-01

    Examination of panel data on listed coal companies on the Australian exchange over January 1999 to February 2010 suggests that market return, interest rate premium, foreign exchange rate risk, and coal price returns are statistically significant in determining the excess return on coal companies’ stock. Coal price return and oil price return increases have statistically significant positive effects on coal company stock returns. A one per cent rise in coal price raises coal company returns ...

  13. reservoir characteristics and palaeo-depositional environment

    African Journals Online (AJOL)

    samsung

    2015-07-25

    Jul 25, 2015 ... Therefore the hydrocarbon accumulation of this field is commercially viable and promising. This study revealed that ... Guinea continental margin in equatorial West Africa between ... onshore Niger Delta and belongs to Addax Petroleum .... GRmin = Gamma Ray value in a nearby clean sand zone. GRmax= ...

  14. A Curse of Coal? Exploring Unintended Regional Consequences of Coal Energy in The Czech Republic

    Directory of Open Access Journals (Sweden)

    Frantál Bohumil

    2014-07-01

    Full Text Available Focusing on coal energy from a geographical perspective, the unintended regional consequences of coal mining and combustion in the Czech Republic are discussed and analysed in terms of the environmental injustice and resource curse theories. The explorative case study attempts to identify significant associations between the spatially uneven distribution of coal power plants and the environmental and socioeconomic characteristics and development trends of affected areas. The findings indicate that the coal industries have contributed to slightly above average incomes and pensions, and have provided households with some technical services such as district heating. However, these positive effects have come at high environmental and health costs paid by the local populations. Above average rates of unemployment, homelessness and crime indicate that the benefits have been unevenly distributed economically. A higher proportion of uneducated people and ethnic minorities in affected districts suggest that coal energy is environmentally unjust.

  15. Coal Data: A reference

    International Nuclear Information System (INIS)

    1991-01-01

    The purpose of Coal Data: A Reference is to provide basic information on the mining and use of coal, an important source of energy in the United States. The report is written for a general audience. The goal is to cover basic material and strike a reasonable compromise between overly generalized statements and detailed analyses. The section ''Coal Terminology and Related Information'' provides additional information about terms mentioned in the text and introduces new terms. Topics covered are US coal deposits, resources and reserves, mining, production, employment and productivity, health and safety, preparation, transportation, supply and stocks, use, coal, the environment, and more. (VC)

  16. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D.K.; Vessell, R.K. [David K. Davies & Associates, Kingwood, TX (United States); Doublet, L.E. [Texas A& M Univ., College Station, TX (United States)] [and others

    1997-08-01

    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  17. Combustion behaviour of ultra clean coal obtained by chemical demineralisation

    Energy Technology Data Exchange (ETDEWEB)

    F. Rubiera; A. Arenillas; B. Arias; J.J. Pis; I. Suarez-Ruiz; K.M. Steel; J.W. Patrick [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2003-10-01

    The increasing environmental concern caused by the use of fossil fuels and the concomitant need for improved combustion efficiency is leading to the development of new coal cleaning and utilisation processes. However, the benefits achieved by the removal of most mineral matter from coal either by physical or chemical methods can be annulled if poor coal combustibility characteristics are attained. In this work a high volatile bituminous coal with 6% ash content was subjected to chemical demineralisation via hydrofluoric and nitric acid leaching, the ash content of the clean coal was reduced to 0.3%. The original and treated coals were devolatilised in a drop tube furnace and the structure and morphology of the resultant chars was analysed by optical and scanning electron microscopies. The reactivity characteristics of the chars were studied by isothermal combustion tests in air at different temperatures in a thermogravimetric system. Comparison of the combustion behaviour and pollutant emissions of both coals was conducted in a drop tube furnace operating at 1000{sup o}C. The results of this work indicate that the char obtained from the chemically treated coal presents very different structure, morphology and reactivity behaviour than the char from the original coal. The changes induced by the chemical treatment increased the combustion efficiency determined in the drop tube furnace, in fact higher burnout levels were obtained for the demineralised coal.

  18. KARAKTERISTIK HABITAT DAN MORFOLOGI SIPUT ONGCOMELANIA HUPENSIS LINDOENSIS SEBAGAI HEWAN RESERVOIR DALAM PENULARAN SHISTOSOMIASIS PADA MANUSIA DAN TERNAK DI TAMAN NASIONAL LORE LINDU (Habitat Characteristics and Morphology of Oncomelania hupensis

    Directory of Open Access Journals (Sweden)

    Hafsah Hafsah

    2013-07-01

    Full Text Available ABSTRAK Penelitian ini bertujuan untuk mengkaji habitat dan morfologi siput Oncomelania hupensis lindoensis sebagai hewan reservoir dalam penularan shistosomiasis pada manusia dan ternak. Penelitian dilakukan dalam kawasan Taman Nasional Lore Lindu. Metode yang digunakan adalah metode survei dengan mengukur dan mengambil beberapa sampel tanah pada beberapa jenis habitat. Siput dikoleksi dengan menggunakan metode gelang besi yang disebut ring method. Siput yang dikumpulkan kemudian dibawa ke laboratorium untuk pengamatan bentuk morfologi dan mirasidia baik secara langsung maupun dengan penggunaan mikroskop. Penentuan tingkat prevalensi digunakan metode “ Kato-Kars” yang dimodifikasi. Data dianalisis secara deskriptif berdasarkan data hasil survei di lapangan dan hasil analisis dari laboratorium. Hasil penelitian menunjukkan bahwa habitat siput O.hupensis Lindoensis yang terdapat dalam kawasan Taman Nasional Lore Lindu sebanyak 144 habitat (fokus dan terdistribusi pada empat desa yaitu Tomado (64 fokus, Anca (63 fokus, Puroo (11 fokus dan Langko (6 fokus dengan persebaran 44,44 % ( sawah, 29,86 % ( kebun, 18,06 % ( padang rumput, dan 11 % ( hutan. Karakteristik habitat yaitu tekstur tanah lempung berpasir dengan bahan organik tanah yang relatif rendah (2%. Pada ternak didapatkan tingkat prevalensi yaitu kerbau (39,36%, sapi (39,32%, dan babi (22,5%. Kesimpulan dari hasil penelitian ini bahwa habitat siput O. Hupensis lindoensis mempunyai karakteristik dan bentuk yang spesifik. Tingkat prevalensi schistosomiasis pada manusia dan ternak dalam kawasan Taman Nasional Lore Lindu masih cukup tinggi. ABSTRACT The objective of the study was evaluated the habitat characteristics and  morphology of  Oncomelania hupensis lindoensis  as  a  reservoir in transmission of Schistosomiasis on  human and animal in Lore Lindu National Park. The study was conducted in four villages as known as the habitat of the endemic snails. Collections of the snails

  19. Opportunities to improve oil productivity in unstructured deltaic reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This report contains presentations presented at a technical symposium on oil production. Chapter 1 contains summaries of the presentations given at the Department of Energy (DOE)-sponsored symposium and key points of the discussions that followed. Chapter 2 characterizes the light oil resource from fluvial-dominated deltaic reservoirs in the Tertiary Oil Recovery Information System (TORIS). An analysis of enhanced oil recovery (EOR) and advanced secondary recovery (ASR) potential for fluvial-dominated deltaic reservoirs based on recovery performance and economic modeling as well as the potential resource loss due to well abandonments is presented. Chapter 3 provides a summary of the general reservoir characteristics and properties within deltaic deposits. It is not exhaustive treatise, rather it is intended to provide some basic information about geologic, reservoir, and production characteristics of deltaic reservoirs, and the resulting recovery problems.

  20. PROBLEMS AND METHODOLOGY OF THE PETROLOGIC ANALYSIS OF COAL FACIES.

    Science.gov (United States)

    Chao, Edward C.T.

    1983-01-01

    This condensed synthesis gives a broad outline of the methodology of coal facies analysis, procedures for constructing sedimentation and geochemical formation curves, and micro- and macrostratigraphic analysis. The hypothetical coal bed profile has a 3-fold cycle of material characteristics. Based on studies of other similar profiles of the same coal bed, and on field studies of the sedimentary rock types and their facies interpretation, one can assume that the 3-fold subdivision is of regional significance.

  1. Characterization and supply of coal-based fuels

    Energy Technology Data Exchange (ETDEWEB)

    1989-06-01

    Contract objectives are as follows: Develop fuel specifications to serve combustor requirements. Select coals having appropriate compositional and quality characteristics as well as an economically attractive reserve base; Provide quality assurance for both the parent coals and the fuel forms; and deliver premium coal-based fuels to combustor developers as needed for their contract work. Progress is discussed, particulary in slurry fuel preparation and particle size distribution.

  2. Coal and public perceptions

    International Nuclear Information System (INIS)

    Porter, R.C.

    1993-01-01

    The Department of Energy's (DOE) clean coal outreach efforts are described. The reason why clean coal technology outreach must be an integral part of coal's future is discussed. It is important that we understand the significance of these advances in coal utilization not just in terms of of hardware but in terms of public perception. Four basic premises in the use of coal are presented. These are: (1) that coal is fundamentally important to this nation's future; (2) that, despite premise number 1, coal's future is by no means assured and that for the last 10 years, coal has been losing ground; (3) that coal's future hinges on the public understanding of the benefits of the public's acceptance of advanced clean coal technology; and (4) hat public acceptance of clean coal technology is not going to be achieved through a nationwide advertising program run by the Federal government or even by the private sector. It is going to be gained at the grassroots level one community at a time, one plant at a time, and one referendum at a time. The Federal government has neither the resources, the staff, nor the mandate to lead the charge in those debates. What is important is that the private sector step up to the plate as individual companies and an individual citizens working one-one-one at the community level, one customer, one civic club, and one town meeting at a time

  3. Indonesian coal export potential

    International Nuclear Information System (INIS)

    Millsteed, Ch.; Jolly, L.; Stuart, R.

    1993-01-01

    Indonesia's coal mining sector is expanding rapidly. Much of the increase in coal production since the mid-1980s has been exported. Indonesian coal mining companies have large expansion programs and continuing strong export growth is projected for the remainder of the 1990s. The low mining costs of indonesian coal, together with proximity to Asian markets, mean that Indonesia is well placed to compete strongly with other thermal coal exporters and win market share in the large and expanding thermal coal market in Asia. However, there is significant uncertainty about the likely future level of Indonesia's exportable surplus of coal. The government's planned expansion in coal fired power generation could constrain export growth, while the ability of producers to meet projected output levels is uncertain. The purpose in this article is to review coal supply and demand developments in Indonesia and, taking account of the key determining factors, to estimate the level of coal exports from Indonesia to the year 2000. This time frame has been chosen because all currently committed mine developments are expected to be on stream by 2000 and because it is difficult to project domestic demand for coal beyond that year. 29 refs., 8 tabs., 7 figs

  4. Coal; Le charbon

    Energy Technology Data Exchange (ETDEWEB)

    Teissie, J.; Bourgogne, D. de; Bautin, F. [TotalFinaElf, La Defense, 92 - Courbevoie (France)

    2001-12-15

    Coal world production represents 3.5 billions of tons, plus 900 millions of tons of lignite. 50% of coal is used for power generation, 16% by steel making industry, 5% by cement plants, and 29% for space heating and by other industries like carbo-chemistry. Coal reserves are enormous, about 1000 billions of tons (i.e. 250 years of consumption with the present day rate) but their exploitation will be in competition with less costly and less polluting energy sources. This documents treats of all aspects of coal: origin, composition, calorific value, classification, resources, reserves, production, international trade, sectoral consumption, cost, retail price, safety aspects of coal mining, environmental impacts (solid and gaseous effluents), different technologies of coal-fired power plants and their relative efficiency, alternative solutions for the recovery of coal energy (fuel cells, liquefaction). (J.S.)

  5. Characteristics of labile organic carbon fractions in reclaimed mine soils: Evidence from three reclaimed forests in the Pingshuo opencast coal mine, China.

    Science.gov (United States)

    Yuan, Ye; Zhao, Zhongqiu; Li, Xuezhen; Wang, Yangyang; Bai, Zhongke

    2018-02-01

    The reclamation of discarded spoils has the potential to stimulate carbon (C) sequestration in reclaimed mine soils (RMSs). Nevertheless, to date the temporal dynamics of labile organic C fractions have not been sufficiently elucidated in RMSs. In this study, soil organic carbon (SOC) and labile organic C fractions, including microbial biomass organic C (MBC), easily oxidizable organic C (EOC) and dissolved organic C (DOC), were determined in Robinia pseudoacacia monoculture forests (reclamation periods of 0, 8, 10, 13, 15, 18 and 30years), Pinus tabuliformis forests (reclamation periods of 0, 10, 19, 23 and 25years) and Ulmus pumila forests (reclamation periods of 0, 18, 20 and 22years) situated on RMSs in the Pingshuo opencast coal mine, China. Changes in labile organic C fractions within the soil profiles (0-100cm) were also identified at the 18- or 19-year plots under the three monoculture forests. Our results showed that, SOC and labile organic C fractions, together with soil microbial quotient (SMQ) and C management index (CMI), increased with time since reclamation, indicating that the quality of RMSs improved over time after initial reclamation under the three forest types. R. pseudoacacia significantly increased the accretion of SOC and EOC in the early stage of reclamation while P. tabuliformis accelerated the accumulation of the MBC fraction. Results for U. pumila indicated that this species had a better ability to store C in RMSs 10years or more after reclamation. SOC and labile organic C fractions both had S-shaped distributions within the soil profiles (0-100cm), with the 0-20cm layer recording the highest values (Pfractions were closely associated and correlated with soil physicochemical properties; our results also showed that nitrogen played an important role in the development of labile organic C fractions. Overall, reclamation accelerated the accretion of both SOC and labile organic C fractions, results of which varied among the reclaimed forests

  6. Geothermal reservoir engineering

    CERN Document Server

    Grant, Malcolm Alister

    2011-01-01

    As nations alike struggle to diversify and secure their power portfolios, geothermal energy, the essentially limitless heat emanating from the earth itself, is being harnessed at an unprecedented rate.  For the last 25 years, engineers around the world tasked with taming this raw power have used Geothermal Reservoir Engineering as both a training manual and a professional reference.  This long-awaited second edition of Geothermal Reservoir Engineering is a practical guide to the issues and tasks geothermal engineers encounter in the course of their daily jobs. The bo

  7. Process for hydrogenating coal and coal solvents

    Energy Technology Data Exchange (ETDEWEB)

    Shridharani, K.G.; Tarrer, A.R.

    1983-02-15

    A novel process is described for the hydrogenation of coal by the hydrogenation of a solvent for the coal in which the hydrogenation of the coal solvent is conducted in the presence of a solvent hydrogenation catalyst of increased activity, wherein the hydrogenation catalyst is produced by reacting ferric oxide with hydrogen sulfide at a temperature range of 260/sup 0/ C to 315/sup 0/ C in an inert atmosphere to produce an iron sulfide hydrogenation catalyst for the solvent. Optimally, the reaction temperature is 275/sup 0/ C. Alternately, the reaction can be conducted in a hydrogen atmosphere at 350/sup 0/ C.

  8. Process for hydrogenating coal and coal solvents

    Science.gov (United States)

    Tarrer, Arthur R.; Shridharani, Ketan G.

    1983-01-01

    A novel process is described for the hydrogenation of coal by the hydrogenation of a solvent for the coal in which the hydrogenation of the coal solvent is conducted in the presence of a solvent hydrogenation catalyst of increased activity, wherein the hydrogenation catalyst is produced by reacting ferric oxide with hydrogen sulfide at a temperature range of 260.degree. C. to 315.degree. C. in an inert atmosphere to produce an iron sulfide hydrogenation catalyst for the solvent. Optimally, the reaction temperature is 275.degree. C. Alternately, the reaction can be conducted in a hydrogen atmosphere at 350.degree. C.

  9. Coal use and coal technology study (KIS)

    International Nuclear Information System (INIS)

    Kram, T.; Okken, P.A.; Gerbers, D.; Lako, P.; Rouw, M.; Tiemersma, D.N.

    1991-11-01

    The title study aims to assess the possible role for coal in the Netherlands energy system in the first decades of the next century and the part new coal conversion technologies will play under various conditions. The conditions considered relate to (sectoral) energy demand derived from national scenarios in an international context, to energy prices, to environmental constraints (acidification, solid waste management and disposal) and to the future role for nuclear power production. Targets for reduction of greenhouse gas emissions are not explicitly included, but resulting CO 2 emissions are calculated for each variant case. The part that coal can play in the Dutch energy supply is calculated and analyzed by means

  10. Geologic coal assessment: The interface with economics

    Science.gov (United States)

    Attanasi, E.D.

    2001-01-01

    Geologic resource assessments describe the location, general characteristics, and estimated volumes of resources, whether in situ or technically recoverable. Such compilations are only an initial step in economic resource evaluation. This paper identifies, by examples from the Illinois and Appalachian basins, the salient features of a geologic assessment that assure its usefulness to downstream economic analysis. Assessments should be in sufficient detail to allocate resources to production units (mines or wells). Coal assessments should include the spatial distribution of coal bed characteristics and the ability to allocate parts of the resource to specific mining technologies. For coal bed gas assessment, the production well recoveries and well deliverability characteristics must be preserved and the risk structure should be specified so dryholes and noncommercial well costs are recovered by commercially successful wells. ?? 2001 International Association for Mathematical Geology.

  11. Nagylengyel: an interesting reservoir. [Yugoslovia

    Energy Technology Data Exchange (ETDEWEB)

    Dedinszky, J

    1971-04-01

    The Nagylengyel oil field, discovered in 1951, has oil-producing formations mostly in the Upper-Triassic dolomites, in the Norian-Ractian transition formations, in the Upper-Cretaceous limestones and shales, and in the Miocene. The formation of the reservoir space occurred in many stages. A porous, cavernous fractured reservoir is developed in the Norian principal dolomite. A cavernous fractured reservoir exists in the Cretaceous limestone and in the Cretaceous shale and porous fractured reservoir is developed in the Miocene. The derivation of the model of the reservoir, and the conservative evaluation of the volume of the reservoir made it possible to use secondary recovery.

  12. Characterization of coal-derived hydrocarbons and source-rock potential of coal beds, San Juan Basin, New Mexico and Colorado, U.S.A.

    Science.gov (United States)

    Rice, D.D.; Clayton, J.L.; Pawlewicz, M.J.

    1989-01-01

    Coal beds are considered to be a major source of nonassociated gas in the Rocky Mountain basins of the United States. In the San Juan basin of northwestern New Mexico and southwestern Colorado, significant quantities of natural gas are being produced from coal beds of the Upper Cretaceous Fruitland Formation and from adjacent sandstone reservoirs. Analysis of gas samples from the various gas-producing intervals provided a means of determining their origin and of evaluating coal beds as source rocks. The rank of coal beds in the Fruitland Formation in the central part of the San Juan basin, where major gas production occurs, increases to the northeast and ranges from high-volatile B bituminous coal to medium-volatile bituminous coal (Rm values range from 0.70 to 1.45%). On the basis of chemical, isotopic and coal-rank data, the gases are interpreted to be thermogenic. Gases from the coal beds show little isotopic variation (??13C1 values range -43.6 to -40.5 ppt), are chemically dry (C1/C1-5 values are > 0.99), and contain significant amounts of CO2 (as much as 6%). These gases are interpreted to have resulted from devolatilization of the humic-type bituminous coal that is composed mainly of vitrinite. The primary products of this process are CH4, CO2 and H2O. The coal-generated, methane-rich gas is usually contained in the coal beds of the Fruitland Formation, and has not been expelled and has not migrated into the adjacent sandstone reservoirs. In addition, the coal-bed reservoirs produce a distinctive bicarbonate-type connate water and have higher reservoir pressures than adjacent sandstones. The combination of these factors indicates that coal beds are a closed reservoir system created by the gases, waters, and associated pressures in the micropore coal structure. In contrast, gases produced from overlying sandstones in the Fruitland Formation and underlying Pictured Cliffs Sandstone have a wider range of isotopic values (??13C1 values range from -43.5 to -38

  13. Effects of coal fly ash on the rheological characteristics of concrete paste and mortar; Zum Einfluss von Steinkohlenflugaschen auf das rheologische Verhalten von Zementleimen und -moerteln

    Energy Technology Data Exchange (ETDEWEB)

    Freimann, T.

    2002-07-01

    stiffening of the paste). Addition of coal fly ashes with low water demand in most cases improves the workability of mortar suspensions. Fly ashes with high water demands reduces the consistency. (orig.)

  14. Clean coal technologies

    International Nuclear Information System (INIS)

    Aslanyan, G.S.

    1993-01-01

    According to the World Energy Council (WEC), at the beginning of the next century three main energy sources - coal, nuclear power and oil will have equal share in the world's total energy supply. This forecast is also valid for the USSR which possesses more than 40% of the world's coal resources and continuously increases its coal production (more than 700 million tons of coal are processed annually in the USSR). The stringent environmental regulations, coupled with the tendency to increase the use of coal are the reasons for developing different concepts for clean coal utilization. In this paper, the potential efficiency and environmental performance of different clean coal production cycles are considered, including technologies for coal clean-up at the pre-combustion stage, advanced clean combustion methods and flue gas cleaning systems. Integrated systems, such as combined gas-steam cycle and the pressurized fluidized bed boiler combined cycle, are also discussed. The Soviet National R and D program is studying new methods for coal utilization with high environmental performance. In this context, some basic research activities in the field of clean coal technology in the USSR are considered. Development of an efficient vortex combustor, a pressurized fluidized bed gasifier, advanced gas cleaning methods based on E-beam irradiation and plasma discharge, as well as new catalytic system, are are presented. In addition, implementation of technological innovations for retrofitting and re powering of existing power plants is discussed. (author)

  15. Coal prices rise

    International Nuclear Information System (INIS)

    McLean, A.

    2001-01-01

    Coking and semi hard coking coal price agreements had been reached, but, strangely enough, the reaching of common ground on semi soft coking coal, ultra low volatile coal and thermal coal seemed some way off. More of this phenomenon later, but suffice to say that, traditionally, the semi soft and thermal coal prices have fallen into place as soon as the hard, or prime, coking coal prices have been determined. The rise and rise of the popularity of the ultra low volatile coals has seen demand for this type of coal grow almost exponentially. Perhaps one of the most interesting facets of the coking coal settlements announced to date is that the deals appear almost to have been preordained. The extraordinary thing is that the preordination has been at the prescience of the sellers. Traditionally, coking coal price fixing has been the prerogative of the Japanese Steel Mills (JSM) cartel (Nippon, NKK, Kawasaki, Kobe and Sumitomo) who presented a united front to a somewhat disorganised force of predominantly Australian and Canadian sellers. However, by the time JFY 2001 had come round, the rules of the game had changed

  16. Japan's New Sunshine Project. 1994 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This paper summarizes the report for fiscal 1994 on research and development related to coal liquefaction and gasification. In the research and development of coal liquefaction technologies, reports were given on research of liquefaction characteristics of different coals and liquefaction process thereof, and on research of catalysts for the coal liquefaction. In the research and development of coal gasification technologies, reports were given on fundamental studies on gasification characteristics of different coals. In the research and development of liquefaction technologies for bituminous coal, reports were given on design, construction and operation of a bituminous coal liquefaction pilot plant with a capacity of 150 t/d, and the operation supporting studies on the pilot plant. In the fundamental research on the coal liquefaction process, reports were given on refining technologies and utilization of the refined materials, and studies on environment preservation in applying the coal liquefaction technologies. In the research on hydrogen manufacturing technologies by using the fundamental coal technology, reports were given on design, construction and operational studies of a pilot plant. In the research and development of the coal gasification technologies, reports were given on development of a jet-flow gasified coal electric power plant, selection of coals, and development of a data processing system. (NEDO)

  17. Japan's New Sunshine Project. 1994 annual summary of coal liquefaction and gasification

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-08-01

    This paper summarizes the report for fiscal 1994 on research and development related to coal liquefaction and gasification. In the research and development of coal liquefaction technologies, reports were given on research of liquefaction characteristics of different coals and liquefaction process thereof, and on research of catalysts for the coal liquefaction. In the research and development of coal gasification technologies, reports were given on fundamental studies on gasification characteristics of different coals. In the research and development of liquefaction technologies for bituminous coal, reports were given on design, construction and operation of a bituminous coal liquefaction pilot plant with a capacity of 150 t/d, and the operation supporting studies on the pilot plant. In the fundamental research on the coal liquefaction process, reports were given on refining technologies and utilization of the refined materials, and studies on environment preservation in applying the coal liquefaction technologies. In the research on hydrogen manufacturing technologies by using the fundamental coal technology, reports were given on design, construction and operational studies of a pilot plant. In the research and development of the coal gasification technologies, reports were given on development of a jet-flow gasified coal electric power plant, selection of coals, and development of a data processing system. (NEDO)

  18. South Blackwater Coal`s maintenance program

    Energy Technology Data Exchange (ETDEWEB)

    Nash, J. [South Blackwater Coal Limited, Blackwater, Qld. (Australia)

    1998-09-01

    The South Blackwater operation consists of two opencut mining areas and two underground mines (Laleham and Kenmure) near Blackwater in central Queensland, all of which supply coal to a central coal preparation plant. South Blackwater Coal Ltd. recently developed a maintenance improvement programme, described in this article. The programme involved implementation systems of key performance indicators (KPIs), benchmaking, condition monitoring, work planning and control, failure analysis and maintenance audit. Some improvements became almost immediately apparent, others were quite gradual. Major results included: improved availability (and reliability) of all opencast fleets, improvements in rear dump availability; reduced maintenance man-hours for opencast fleets; and increased availability of the coal handling and preparation plant. The paper is an edited version of that presented at the `Maintenance in mining conference` 16-19 March 1998, held in Bali, Indonesia. 4 figs., 2 photos.

  19. Comparison of static and dynamic resilience for a multipurpose reservoir operation

    Science.gov (United States)

    Simonovic, Slobodan P.; Arunkumar, R.

    2016-11-01

    Reliability, resilience, and vulnerability are the traditional risk measures used to assess the performance of a reservoir system. Among these measures, resilience is used to assess the ability of a reservoir system to recover from a failure event. However, the time-independent static resilience does not consider the system characteristics, interaction of various individual components and does not provide much insight into reservoir performance from the beginning of the failure event until the full performance recovery. Knowledge of dynamic reservoir behavior under the disturbance offers opportunities for proactive and/or reactive adaptive response that can be selected to maximize reservoir resilience. A novel measure is required to provide insight into the dynamics of reservoir performance based on the reservoir system characteristics and its adaptive capacity. The reservoir system characteristics include, among others, reservoir storage curve, reservoir inflow, reservoir outflow capacity, and reservoir operating rules. The reservoir adaptive capacity can be expressed using various impacts of reservoir performance under the disturbance (like reservoir release for meeting a particular demand, socioeconomic consequences of reservoir performance, or resulting environmental state of the river upstream and downstream from the reservoir). Another way of expressing reservoir adaptive capacity to a disturbing event may include aggregated measures like reservoir robustness, redundancy, resourcefulness, and rapidity. A novel measure that combines reservoir performance and its adaptive capacity is proposed in this paper and named "dynamic resilience." The paper also proposes a generic simulation methodology for quantifying reservoir resilience as a function of time. The proposed resilience measure is applied to a single multipurpose reservoir operation and tested for a set of failure scenarios. The dynamic behavior of reservoir resilience is captured using the system

  20. Parallel reservoir simulator computations

    International Nuclear Information System (INIS)

    Hemanth-Kumar, K.; Young, L.C.

    1995-01-01

    The adaptation of a reservoir simulator for parallel computations is described. The simulator was originally designed for vector processors. It performs approximately 99% of its calculations in vector/parallel mode and relative to scalar calculations it achieves speedups of 65 and 81 for black oil and EOS simulations, respectively on the CRAY C-90

  1. A study on the combustion behaviour of coal blends

    Energy Technology Data Exchange (ETDEWEB)

    Rubiera, F.; Fuente, E.; Arenillas, A.; Pis, J.J. [Instituto Nacional del Carbon, Oviedo (Spain)

    1999-07-01

    Combustion behaviour of four coals of varying rank and their binary blends was studied using temperature programmed combustion tests, and thermogravimetric analysis. Characteristic parameters could not be predicted from the weight percentage of individual coals in the blend. 6 refs., 4 figs., 1 tab.

  2. The chemical composition of tertiary Indian coal ash and its

    Indian Academy of Sciences (India)

    In Part 1 of the present investigation, 37 representative Eocene coal samples of Meghalaya, India were analyzed and their physico-chemical characteristics and the major oxides and minerals present in ash samples were studied for assessing the genesis of these coals. Various statistical tools were also applied to study ...

  3. Stress and Damage Induced Gas Flow Pattern and Permeability Variation of Coal from Songzao Coalfield in Southwest China

    Directory of Open Access Journals (Sweden)

    Minghui Li

    2016-05-01

    Full Text Available The permeability of coal is a critical parameter in estimating the performance of coal reservoirs. Darcy’s law describes the flow pattern that the permeability has a linear relationship with the flow velocity. However, the stress induced deformation and damage can significantly influence the gas flow pattern and permeability of coal. Coals from Songzao coalfield in Chongqing, southwest China were collected for the study. The gas flow velocities under different injection gas pressures and effective stresses in the intact coal and damaged coal were tested using helium, incorporating the role of gas flow pattern on the permeability of coal. The relationships between the flow velocity and square of gas pressure gradient were discussed, which can help us to investigate the transformation conditions of gas linear flow and gas nonlinear flow in the coal. The results showed that the gas flow in the intact coal existed pseudo-initial flow rate under low effective stress. The low-velocity non-Darcy gas flow gradually occurred and the start-up pressure gradient increased in the coal as the effective stress increased. The gas flow rate in the damaged coal increased nonlinearly as the square of pressure gradient increased under low effective stress. The instability of gas flow caused by high ratio of injection gas pressure over effective stress in the damaged coal contributed to the increase of the gas flow rate. As the effective stress increased, the increase of gas flow rate in coal turned to be linear. The mechanisms of the phenomena were explored according to the experimental results. The permeability of coal was corrected based on the relationships between the flow velocity and square of gas pressure gradient, which showed advantages in accurately estimating the performance of coal reservoirs.

  4. Recommended procedures and methodology of coal description

    Science.gov (United States)

    Chao, E.C.; Minkin, J.A.; Thompson, C.L.

    1983-01-01

    This document is the result of a workshop on coal description held for the Branch of Coal Resources of the U.S. Geological Survey in March 1982. It has been prepared to aid and encourage the field-oriented coal scientist to participate directly in petrographic coal-description activities. The objectives and past and current practices of coal description vary widely. These are briefly reviewed and illustrated with examples. Sampling approaches and techniques for collecting columnar samples of fresh coal are also discussed. The recommended procedures and methodology emphasize the fact that obtaining a good megascopic description of a coal bed is much better done in the laboratory with a binocular microscope and under good lighting conditions after the samples have been cut and quickly prepared. For better observation and cross-checking using a petrographic microscope for identification purposes, an in-place polishing procedure (requiring less than 2 min) is routinely used. Methods for using both the petrographic microscope and an automated image analysis system are also included for geologists who have access to such instruments. To describe the material characteristics of a coal bed in terms of microlithotypes or lithotypes, a new nomenclature of (V), (E), (1), (M). (S). (X1). (X2) and so on is used. The microscopic description of the modal composition of a megascopically observed lithologic type is expressed in terms of (VEIM); subscripts are used to denote the volume percentage of each constituent present. To describe a coal-bed profile, semiquantitative data (without microscopic study) and quantitative data (with microscopic study) are presented in ready-to-understand form. The average total composition of any thickness interval or of the entire coal bed can be plotted on a triangular diagram having V, E, and I+ M +S as the apices. The modal composition of any mixed lithologies such as (X1), (X2), and so on can also be plotted on such a triangular ternary diagram

  5. Coal comes clean

    International Nuclear Information System (INIS)

    Minchener, A.

    1991-01-01

    Coal's status as the dominant fuel for electricity generation is under threat because of concern over the environmental impacts of acid rain and the greenhouse effect. Sulphur dioxide and nitrogen oxides cause acid rain and carbon dioxide is the main greenhouse gas. All are produced when coal is burnt. Governments are therefore tightening the emission limits for fossil-fuel power plants. In the United Kingdom phased reductions of sulphur dioxide and nitrogen oxides emissions are planned. It will be the responsibility of the power generator to take the necessary steps to reduce the emissions. This will be done using a number of technologies which are explained and outlined briefly - flue gas desulfurization, separation of coal into high and low-sulphur coal, direct desulfurization of coal, circulating fluidised bed combustion, integrated-gasification combined cycle systems and topping cycles. All these technologies are aiming at cleaner, more effi