Showing papers on "Coal published in 2002"
TL;DR: In this paper, a brief review of the organic matter composition in aerosols derived from the major sources is also given, with emphasis on the detection of biomass burning components, and a long range transport of smoke particulate matter with the associated organic compounds is also discussed.
1,325 citations
TL;DR: An overview on the methodologies for zeolite synthesis from CFA, and a detailed description of conventional alkaline conversion processes, with special emphasis on the experimental conditions to obtain high cation exchange capacity (CEC) zeolites is given in this article.
792 citations
TL;DR: A range of technologies, including but not restricted to low-temperature oxygen-plasma ashing, may be used to evaluate the total proportions of minerals and other inorganic constituents in a coal sample as mentioned in this paper.
702 citations
TL;DR: In this paper, a comprehensive, spatially resolved (0.25°×0.75°) fossil fuel consumption database and emissions inventory was constructed, for India, for the first time, and emissions for various pollutants were derived using India specific fuel characteristics and information on combustion/air pollution control technologies for the power and industrial sectors.
419 citations
TL;DR: In this paper, the quality requirements of metallurgical coke for the blast furnace, coke structure, and relationships between structure and quality are reviewed. And a review of current coke production and coal demand in the steelmaking industry, globally, followed by a preview of possible future alternative coking technologies.
401 citations
TL;DR: The working hypothesis is that groundwater is leaching toxic organic compounds as it passes through the lignites and that these organics are then ingested by the local population contributing to this health problem.
387 citations
Patent•
24 Oct 2002TL;DR: In this article, a method for treating coal formations to alter properties of coal in the formation is provided, where heat from one or more heaters may be provided to at least a portion of the formation.
Abstract: A method for treating a coal formation to alter properties of coal in the formation is provided. In one embodiment, heat from one or more heaters may be provided to at least a portion of the formation. Heat may be allowed to transfer from the one or more heaters to a part of the formation. In certain embodiments, the heat from the one or more heaters may pyrolyze at least some hydrocarbons within the part of the formation. The method may include producing a fluid from the formation. In some embodiments, the produced fluid may include at least some pyrolyzed hydrocarbons from the formation. In an embodiment, after at least some coal has been treated at least a portion of such coal may be produced from the formation.
320 citations
TL;DR: Investigation on color removal of trisazo direct dye and activated carbon indicated that the coal based sorbents facilitated chemisorption in the process of dye sorption while, activated carbon resulted in physisor adaptation interaction.
320 citations
TL;DR: In this paper, two coal chars were gasified with carbon dioxide or steam using a Pressurized Drop Tube Furnace (PDTF) at high temperature and pressurized conditions to simulate the inside of an air-blown two-stage entrained flow coal gasifier.
315 citations
TL;DR: Coal may become more important both as an energy source and as the source of organic chemical feedstock in the 21st century as discussed by the authors, and coal has several positive attributes when considered as a feedstock for aromatic chemicals, specialty chemicals, and carbon-based materials.
314 citations
TL;DR: In this article, a set of brown coal samples was pyrolysed in a thermogravimetric analyser and in a novel fluidised-bed/fixed-bed reactor.
TL;DR: In this article, the effect of operating pressure on coal reactions has been investigated and it has been shown that higher reactant pressure enhances coal combustion and gasification reaction rate, which can be understood by an adsorption-desorption mechanism.
TL;DR: In this paper, the authors conduct a Life Cycle Assessment (LCA) to compare the environmental impacts of electricity production via coal firing versus coal/algae cofiring, and demonstrate that there are potentially significant benefits to recycling CO 2 toward microalgae production as it reduces CO 2 emissions by recycling it and uses less coal.
TL;DR: In this paper, the authors investigated the devolatilization behavior of different coals and biomasses under heating conditions typical of conventional pyrolysis processes and found that coal does not seem to be influenced by the release of volatile matter from biomass.
TL;DR: In this article, the potential for high gas content is controlled directly by the amount of thermogenic and secondary biogenic gases generated from the coal which in turn are controlled by burial history, maceral composition, and basin hydrodynamics.
TL;DR: A review of the problems involved with coal petrology as it is usually practiced can be found in this article, where a holistic approach to studies of coal and coal macerals, which includes not only petrographic but also chemical and biological studies, is advocated.
TL;DR: In this article, analytical methods for inorganics in coal are reviewed on three fronts: (i) elemental concentrations, (ii) methods for determining the mineralogy of coals, and (iii) method for determining modes of occurrence (speciation) of trace elements in coal.
Patent•
25 Nov 2002
TL;DR: In this paper, coal syngas or other coal fired power plant is provided with no atmospheric emissions, where coal or other starter fuel is gasified within a gasifier which also receives oxygen and steam therein.
Abstract: A coal syngas or other syngas fired power plant is provided with no atmospheric emissions. Coal or other starter fuel is gasified within a gasifier which also receives oxygen and steam therein. The oxygen is provided from an air separator. Syngas produced within the gasifier is combusted within a gas generator along with oxygen from the air separator. Water is also introduced into the gas generator to control the temperature of combustion of the syngas with the oxygen. Products of combustion including steam and carbon dioxide are produced within the gas generator. The combustion products are expanded through a turbine for power output and then separated, such as within a condenser. Water discharged from the condenser is at least partially recirculated back to the gasifier and the gas generator. Carbon dioxide from the separator is compressed for capture without release into the atmosphere.
TL;DR: In this paper, coal, CaO and CO reactions with steam, and CO2 absorption by Ca(OH)2 or CaO occurred simultaneously in the experiment and it was found that H2 was the primary resultant gas, comprising about 85% of the reaction products.
TL;DR: In this article, the effect of heat treatment on the structure of an Australian semi-anthracite char was studied in detail in the 850-1150degreesC temperature range using XRD, HRTEM, and electrical resistivity techniques.
TL;DR: In this paper, it was shown that the chemical and physical form of sodium in brown coal is an important factor influencing the volatilisation of sodium during pyrolysis.
TL;DR: In this paper, the authors used the devolatilisation pre-processor code to compute pyrolysis rate, the yields and the composition of volatiles and char.
TL;DR: In this paper, a coal porosity system was determined in relation to the molecular size of different gases, such as helium, nitrogen, carbon dioxide, and methane, and the experimental conditions of the sorption process were as follows: temperature in the bath 35 °C; sample with moisture equal to or greater than the moisture-holding capacity (MHC), particle size of sample less than 212 μm, and mass ca. 100 g.
TL;DR: In this paper, the effect of coal properties on CWSs have been investigated using two Turkish coals of different ranks and a Siberian bituminous coal, and the results showed that coal-water slurries have a similar viscosity as water slurries.
TL;DR: In this article, the effects of cofiring biomass and coal on ash deposition under conditions representative of those found in the superheater region of pulverized-coal boilers were examined.
Abstract: Cofiring biomass with coal is a promising short-term option for reducing the net CO2 emissions from existing coal-fired power plants. This paper examines the effects of cofiring biomass and coal on ash deposition under conditions representative of those found in the superheater region of pulverized-coal boilers. Experiments were conducted with blends of eight different fuelsthree types of bituminous coal, sub-bituminous coal, two types of straw, switchgrass, and wood. For each fuel, reference tests of unblended fuel establish a baseline against which to compare the results from the cofiring tests. The deposition rates for the cofire blends are between the measured deposition rates of the unblended fuels. Therefore, blending straw with coal reduces the high deposition rates observed while firing unblended straw, and cofiring coal with wood results in slightly lower deposition rates than those that occur while firing unblended coal. The primary interaction between the biomass and coal during cofiring is the...
TL;DR: In this paper, a review of coal analysis is presented, focusing on the macromolecular structure of coal, the contribution of relatively low molecular substances in the structure, and the factors that influence solvent extraction capability.
TL;DR: In this paper, the mass loss during the transformation of coal mineral matter during combustion can be modeled as a mixture of individual coal minerals in inert and oxidizing atmospheres, and the reaction with gaseous atmosphere was described by first order reactions.
KEMA1
TL;DR: The fate of the Hg during combustion was established by performing mass balance studies, and during co-combustion with biomass, the removal of Hg was similar to that during 100% coal firing.
Abstract: For the past 22 years in the Netherlands, the behavior of Hg in coal-fired power plants has been studied extensively. Coal from all over the world is fired in Dutch power stations. First, the Hg concentrations in these coals were measured. Second, the fate of the Hg during combustion was established by performing mass balance studies. On average, 43 +/- 30% of the Hg was present in the flue gases downstream of the electrostatic precipitator (ESP; dust collector). In individual cases, this figure can vary between 1 and 100%. Important parameters are the Cl content of the fuel and the flue gas temperature in the ESP. On average, 54 +/- 24% of the gaseous Hg was removed in the wet flue-gas desulfurization (FGD) systems, which are present at all Dutch coal-power stations. In individual cases, this removal can vary between 8% (outlier) and 72%. On average, the fate of Hg entering the power station in the coal was as follows: <1% in the bottom ash, 49% in the pulverized fuel ash (ash collected in the ESP), 16.6% in the FGD gypsum, 9% in the sludge of the wastewater treatment plant, 0.04% in the effluent of the wastewater treatment plant, 0.07% in fly dust (leaving the stack), and 25% as gaseous Hg in the flue gases and emitted into the air. The distribution of Hg over the streams leaving the FGD depends strongly on the installation. On average, 75% of the Hg was removed, and the final concentration of Hg in the emitted flue gases of the Dutch power stations was only -3 microg/m3(STP) at 6% O2. During co-combustion with biomass, the removal of Hg was similar to that during 100% coal firing. Speciation of Hg is a very important factor. An oxidized form (HgCl2) favors a high degree of removal. The conversion from Hg0 to HgCl2 is positively correlated with the Cl content of the fuel. A catalytic DENOX (SCR) favors the formation of oxidized Hg, and, in combination with a wet FGD, the total removal can be as high as 90%.
TL;DR: In this article, the pyrolytic properties of woody biomass/coal mixtures were investigated under both low and high heating rate conditions over a range of temperatures between 200°C and 1400°C.
Abstract: Pyrolytic behaviours of woody biomass/coal mixtures were investigated under both low and high heating rate conditions over a range of temperatures between 200°C and 1400°C. Results obtained from this comprehensive investigation indicated that the pyrolytic characteristics of the mixtures follow those of the parent materials in an additive manner. Therefore, under inert (non-oxidising) conditions the two fuels undergo independent thermal conversion without any chemical interactions. As such, the yield of the major pyrolysis products (e.g. volatiles and char) is proportional to the percentage of woody biomass and coal in the mixture. This confirms the hypothesis made by a number of researchers about the lack of synergistic effects in the yield of pyrolysis products from blended coal and woody biomass. However, in this study, we show that even the compositions of the gaseous products from blended samples are linearly proportional to those of their parent fuels (lack of synergistic effects). These findings can potentially help to understand and predict the behaviour of woody biomass/coal blends in practical combustion systems.
TL;DR: In this article, the effect of co-combustion of coal and biomass has been studied for a fixed bed appliance originally designed for coal and in widespread use in many parts of the world especially Eastern Europe.