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Low-pressure adsorption experiments with carbon dioxide on dry and moisture-equilibrated coal samples from the Ruhr basin, Germany at 273, respectively, 275K have been carried out in order to obtain information about pore structure, its interaction with water and development with rank. The range of rank of the samples varies between 0.76 and 2.23% vitrinite reflectance VRr. The evaluation of structural...
Methyl esters of vegetable oils have been successfully evaluated as diesel substitute. In the present study, other alkyl esters, namely ethyl and isopropyl esters of crude palm oil and crude palm stearin were synthesized via chemical transesterification reactions and subsequently evaluated for their fuel properties. Generally, these alkyl esters exhibit higher viscosity (4.4×10 −6 m 2...
A wire-mesh reactor capable of multi-step heating/holding and minimising secondary reactions of volatiles was used to investigate the effects of thermal pretreatment in inert gas on the subsequent rapid pyrolysis behaviour of Loy Yang brown coal. Our results indicate that the presence of small amounts (<10wt%) of moisture in brown coal has little influence on the tar and char yields from the pyrolysis...
Alternative fuels exhibit different features respect to traditional fuels and require an experimental characterization in conditions similar to those of practical applications (high temperature, high heating rate, low residence time).In this work, a lab-scale drop tube reactor is characterized and an experimental procedure is developed to test a bituminous coal and a biomass fuel at high heating rate...
In the present study, the potential for products other than CaCl 2 to be formed during HCl absorption was studied to shed light on the mechanisms of limestone chlorination. Experiments of different durations were made with a thermogravimetric apparatus, and the crystalline reaction products were identified by X-ray diffractometry (XRD). In the experiments, absorption products with Cl/Ca molar...
Unrefined biodiesels containing small quantities of monoglycerides, diglycerides, and triglycerides, and refined biodiesels not containing these glycerides were added to diesel fuel and the resulting lubricity was measured using the High Frequency Reciprocating Rig (HFRR) method. The unrefined biodiesels showed higher lubricity properties than refined biodiesels. The chemical factors influencing the...
In this work, dry desulphurization of simulated flue gas was investigated in a laboratory-scale stainless steel fluidized-bed reactor (46×500mm 2 ) by using calcium-containing local Turkish limestone (Karaağaçlı/MUŞ) which was calcined at 900°C with 5% H 2 O vapour. The fluidized-bed reactor (FBR) was operated batchwise with a single charge of (15g) particles for obtaining SO 2...
A blend of 20% (v/v) ethanol/methyl soyate was prepared and added to diesel fuel as an oxygenated additive at volume percent levels of 15 and 20% (denoted as BE15 and BE20). We also prepared a blend containing 20% methyl soyate in diesel fuel (denoted as B20). The fuel blends that did not have any other additive were stable for up to 3 months. Engine performance and emission characteristics of the...
Artificial neural networks (ANN) are powerful tools that can be used to model and investigate various highly complex and non-linear phenomena. This paper describes the development and training of a feed-forward back-propagation artificial neural network (BPNN), which is used to predict the hydrogen content in coal from proximate analysis. The ultimate objective is to enhance the performance of the...
A new process for converting coal fly ash to an artificial zeolite is described. The process is comprised of a high-temperature operation and water removal during the operation. Suitable operation parameters of the process were investigated using a test unit, and the optimal conditions were found to be 2.5–3.5mol/dm 3 of NaOH and 0.88–1.10dm 3 /kg of liquid/solid, sodium hydroxide...
This study develops equivalent reactor networks from the CFD simulations for the pressurized coal flames described in Part 1, and quantitatively interprets the data by applying detailed reaction mechanisms across the reactor networks. These simulations depict all the important trends in the database with both coal quality and increasing pressure. The only quantitative discrepancy is that CO yields...
The conversion of Canadian oil sand bitumen was remarkably enhanced by oxidation pretreatment during hydro-thermal cracking. The reaction mechanism was discussed from elemental analysis, NMR results as well as reaction behavior, suggesting that the peroxide or its free radical might be formed by oxidation of heavy oils. Hydrogen in hydrocarbon might be easily abstracted via formation and successive...
Steam gasification of nascent char from rapid or slow pyrolysis of a Victorian brown coal was performed at 1073–1173K in a novel drop-tube/fixed-bed reactor, in which steam-containing gas was forced to pass through an extremely thin bed of nascent char particles at sufficiently high velocity and large flux. The nascent char underwent parallel reactions consisting of non-catalytic gasification and...
The tests and simulations in this study characterize the chemical structure of pressurized pulverized coal flames, particularly (1) how the O 2 in simulated near-burner flame zones is apportioned among the various fuel components; and (2) the burner operating conditions and mechanisms that most strongly affect flame structure. CFD simulations resolved the structures of flames of a subbituminous...
Co-gasification of bagasse wastes mixed with coal is technically feasible, without major installation changes. The effect of experimental conditions on co-gasification process was analysed, to enhance gas production and improve its composition and energetic content. The rise of bagasse content increased tars and gaseous hydrocarbons contents, which can be reduced by increasing gasification temperature...
In the present work, the objective was to elaborate the chemistry of limestone and HCl in hot flue gases, especially under conditions that are typical of fluidised bed combustors. The effects of temperature, absorbent quality and particle size as well as gas atmosphere on the absorption reactions of HCl have been investigated, as have the products of chlorination. In addition, special emphasis was...
Al-MCM-41 type mesoporous catalysts were used for converting the pyrolysis vapours of spruce wood in order to obtain better bio-oil properties. Four Al-MCM-41 type catalysts with a Si/Al ratio of 20 were tested. The catalytic properties of Al-MCM-41 catalyst were modified by pore enlargement that allows the processing of larger molecules and by introduction of Cu cations into the structure.Spruce...
A previous one-dimensional numerical isothermal model of a fluidised-bed coal gasifier has been further improved to consider the non-isothermal behaviour of gases and heat transfer mechanisms in the fluidised-bed. Comparisons were made with data simulating the performance of a full-scale fluidised-bed coal gasifier, a 2MWth pilot plant and a laboratory-scale bed. Simulation results indicate that comparisons...
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