Fuel and Energy Abstracts

5/21/2018 Fuel and Energy Abstracts

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01 SOLID FUELS

Sources, winning, properties

13/00001 A new technological classification of low-rankcoal on the basis of Polish deposits

Bielowicz, B. Fuel, 2012, 96, 497510.Proposed technological classification of low-rank coal has two stages.The first part, presented in graphic form, sets the rank of coal, grade ofcoal and its petrographic character. In order to assess the rank anddistinguish various subcategories of low-rank coal, random reflectanceof ulminite B/collotelinite has been applied. Simplified petrographiccomposition of humic coal allowed on the basis of the content ofmacerals from huminite group (vitrinite for bright brown coal) todistinguish subcategories of low rank coal. Ash content of coalrecalculated to dry basis determines in proposed first stage of theclassification the grade of coal. The second stage of technologicalclassification is presented as a codification system, while it dis-tinguishes following types of low rank coal: energetic coal (type 21),coal for gasification (type 22) as well as coal for liquefaction (type 23).Coal types are defined through chemical, technological and petro-graphic criteria. Every single type of low-rank coal has its own uniquetechnological code, consisting of main and supplementary parameters.Main code allows one to determine the possibility of its use in certaintechnologies, while supplementary code precisely characterizes theparameters important for those applications. Technological quality of

tested coal has been presented with use of code number, which digitshave been set on the basis of division into classes within testedparameters.

13/00002 Black shales in Ukraine a reviewSachsenhofer, R. F. and Koltun, Y. V. Marine and Petroleum Geology,2012, 31, (1), 125136.

As a resul t of a long-l astin g and comple x geologi cal histor y, organi c-matter-rich fine-grained rocks (black shales) with widely varying agescan be found on Ukrainian territory. Several of them are provenhydrocarbon source rocks and may hold a significant shale gaspotential. Thick Silurian black shales accumulated along the westernmargin of the East European Craton in a foreland-type basin. Byanalogy with coeval organic-matter-rich rocks in Poland, high TOCcontents and gas window maturity can be expected. However, to dateinformation on organic richness is largely missing and maturitypatterns remain to be refined. Visean black shales with TOC contentsas high as 8% and a Type III-II kerogen accumulated along the axis ofthe Dniepr-Donets rift basin (DDB). They are the likely source forconventional oil and gas. Oil-prone Serpukhovian black shalesaccumulated in the shallow northwestern part of the DDB. Similarblack shales probably may be present in the Lviv-Volyn Basin (westernUkraine). Middle Jurassic black shales up to 500 m thick occur beneaththe Carpathian Foredeep. They are the likely source for some heavy oildeposits. TOC contents up to 12% (Type II) have been recorded, butadditional investigations are needed to study the vertical and lateral

variab ility of organi c matte r rich ness and matur ity. Lower Creta ceousblack shales with a Type III(-II) kerogen (TOC> 2%) are widespreadat the base of the Carpathian flysch nappes, but Oligocene black shales(Menilite Fm.) rich in organic matter (48% TOC) and containing aType II kerogen are the main source rock for oil in the Carpathians.Their thermal maturity increases from the external to the internalnappes. Oligocene black shales are also present in Crimea (MaykopFm.). These rocks typically contain high TOC contents, but data fromUkraine are missing.

13/00003 Environmental geochemistry of the feed coalsand their combustion by-products from two coal-fired powerplants in Xinjiang Province, northwest China

Li, J. et al. Fuel, 2012, 95, 446456.The mineralogical and geochemical characteristics of feed coals andtheir combustion by-products (fly ash and slag) from Hongyanchi(HONG) and Weihuliang (WEI) coal-fired power plants in XinjiangProvince, north-west China, were investigated. The enrichment andpartitioning behaviour, as well as the leaching potential of the majorand trace elements in these combustion by-products were evaluated.Three feed coals from the two power plants (HC, WC 1, and WC2) werecharacterized by medium-moisture contents, low- to medium-ash

yields , high volati le matter s, and low-S conten ts as well as low-mi neralcontents. Except B, Sr, and Ba in WC1feed coal; P, Ti, V, Cr, Mn, Cu,Zn, Rb and Ba in WC2feed coal; and Ti, Mn, Cu, Zn, Rb, Sr and Ba inthe HC feed coal, most major and trace element concentrations werelow compared with other Chinese coals and coals worldwide. Mosttrace element concentrations in the studied fly ashes (HA, WAf and

WAc) were even lower than their minimum and/or 25th percentile(P25) values reported for European Union fly ashes, as were theelement concentrations in the fly ash leachates. The studied fly ashes

were all classi fied as t ype F f ly a shes, with high glass conten ts as well ashigh SiO2/Al2O3ratios in the glass matrix. Through enrichment factors,mass balance, and partitioning of elements, S, F, Cl, Hg and B werehighly volatile in both PCC plants. Tin, As, Se, Cu and Zn were alsomoderately volatile, and they were enriched in fly ashes mainly by

volati lizat ion/con densat ion. Iron and Mn were sligh tly enric hed inslags, probably due to the high density of FeMn-bearing phases. In thelight of the above-mentioned properties, fly ashes and slags from thetwo power plants in Xinjiang will have a very high potential for a

variet y of uses, with very low environ menta l limit ations . In summ ary,this study is demonstrating the high quality of Xinjiang coals withenormous coal reserves, and also the high quality of the combustion by-products that will be produced also in very high amounts in the nearfuture. Major focus is on trace elements.

13/00004 Investigation of the influence of coal swelling onpermeability characteristics using natural brown coal andreconstituted brown coal specimensJasinge, D. et al. Energy, 2012, 39, (1), 303309.Permeability has been identified as one of the foremost factors thatdetermine the effectiveness of CO2 sequestration in deep coalbeds.Coal matrix swelling can cause a remarkable decrease in thepermeability of a coalbed reservoir during the carbon dioxide injectionprocess. The main aim of this paper is to correlate the diametricalswelling percentage with coal permeability. This experimental programfurther attempts to investigate the effect of gas flow properties in coaldue to CO2 sorption. Furthermore, the applicability of using alaboratory-made reconstituted coal specimen for permeability testing

has been comprehensively investigated. A laboratory-based experimen-tal program has been carried out using a high pressure triaxialexperimental set-up. In this study, the effect of swelling on coalpermeability has been investigated using two types of specimens. Anintact brown coal specimen cored from a natural coal block and areconstituted brown coal specimen made by compacting coal dust in amould has been subjected to testing. Tests have been carried out underdifferent gas injection and confining pressures. CO2and N2gases havebeen used as injection media. Gas injection has been carried out withtwo stages of N2injection, prior to and after CO2injection. Diametricalswelling of the two specimens has been compared with the permeabilitydata. A good correlation was observed between permeability and coalswelling. The coal swelling percentage increased on exposure to carbondioxide compared to exposure to N2. This effect increased as gasinjection pressure increased. Exposure of the coal specimens to CO2has contributed to a detrimental effect on permeability. This wasclearly evident during the second injection of N2 gas.

13/00005 Organic geochemistry and petrology of

subsurface PaleoceneEocene Wilcox and Claiborne Groupcoal beds, Zavala County, Maverick Basin, Texas, USAHackley, P. C. et al. Organic Geochemistry, 2012, 46, 137153.Coal samples from a coalbed methane exploration well in northernZavala County, Maverick Basin, Texas, were characterized through anintegrated analytical program. The well was drilled in February 2006and shut in after coal core desorption indicated negligible gas content.Cuttings samples from two levels in the Eocene Claiborne Group wereevaluated by way of petrographic techniques and RockEval pyrolysis.Core samples from the PaleoceneEocene Indio Formation (WilcoxGroup) were characterized via proximateultimate analysis in additionto petrography and pyrolysis. Two Indio Formation coal samples wereselected for detailed evaluation via gas chromatography, and Fouriertransform infrared and 13C CPMAS NMR spectroscopy. Samples aresubbituminous rank as determined from multiple thermal maturityparameters. Elevated rank (relative to similar age coal beds elsewherein the Gulf Coast Basin) in the study area is interpreted to be a resultof stratigraphic and/or structural thickening related to Laramidecompression and construction of the Sierra Madre Oriental to thesouthwest. Vitrinite reflectance data, along with extant data, suggest

the presence of an erosional unconformity or change in regional heatflow between the Cretaceous and Tertiary sections and erosion of up to>5 km over the Cretaceous. The presence of liptinite-rich coals in theClaiborne at the well site may indicate moderately persistent orrecurring coal-forming paleoenvironments, interpreted as perenniallysubmerged peat in shallow ephemeral lakes with herbaceous and/orflotant vegetation. However, significant continuity of individual Eocenecoal beds in the subsurface is not suggested. Indio Formation coalsamples contain abundant telovitrinite interpreted to be preservedfrom arborescent, above-ground woody vegetation that developedduring the middle portion of mire development in forested swamps.Other petrographic criteria suggest enhanced biological, chemical andphysical degradation at the beginning and end of Indio miredevelopment. Fluorescence spectra of sporinite and resinite areconsistent and distinctly different from each other, attributed to the

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presence of a greater proportion of complex asphaltene and polarmolecules in resinite. Gas chromatography of resinite-rich coal showssesquiterpenoid and diterpenoid peaks in the C1417range, which arenot present in resinite-poor coal. Quantities of extracts suggestbitumen concentration below the threshold for effective source rocks[3050mg hydrocarbon/g total organic carbon (HC/g TOC)]. Saturate/aromatic and pristane/phytane (Pr/Ph) ratios are different from valuesfor nearby Tertiary-reservoired crude oil, suggesting that the Indiocoals are too immature to source liquid hydrocarbons in the area.However, moderately high HI values (200400mg HC/g rock) maysuggest some potential for naphthenicparaffinic oil generation whereburied more deeply down stratigraphic/structural dip. Extractablephenols and C20+ alkanes are suggested as possible intermediates foracetate fermentation in microbial methanogenesis which may, however,be limited by poor nutrient supply related to low rainfall and meteoricrecharge rate or high local sulfate concentration.

13/00006 Relationships between the sorption behaviour ofmethane, carbon dioxide, nitrogen and ethane on coalsSakurovs, R. et al. Fuel, 2012, 97, 725729.Sequestration of carbon dioxide in coal seams can reduce emissions ofcarbon dioxide to the atmosphere. If such sequestration simultaneouslyresults in enhanced coal bed methane (ECBM) production, some of thesequestration costs can be recovered by the value of the methaneproduced. This requires knowledge of both the carbon dioxide andmethane sorption behaviour of coal at high pressures. In order toelucidate the connection between them, the authors investigated thesorption of carbon dioxide, methane, ethane and nitrogen at 55 C atpressures up to 20 MPa for a number of coals. Sorption isotherms werefitted by a modified DubininRadushkevich model. The maximumsorption capacities of the coals for the different gases were found to be

highly correlated. The relationship between maximum sorptioncapacity of a coal for a gas and its critical temperature was approxi-mately proportional. The relationship between methane and nitrogenmaximum sorption capacity was particularly close: on a volume basis,the maximum sorption capacity of all coals examined for methane wastwice that of nitrogen. The ratio of maximum sorption capacity ofcarbon dioxide and methane decreased linearly with increasing carboncontent. The ethane/methane sorption ratio also tended to decrease

with incre asing rank though to a smal ler extent , indic ating that theproportionally greater sorption at low rank coals is not unique tocarbon dioxide. The heat of sorption tends to increase with increasing

vitri nite reflec tance ; th is may reflec t t he g reater polari zabili ty o f h igherrank coals (which also determines their reflectance).

13/00007 The characteristics of the biomarkers andd13C ofn-alkanes released from thermally altered solid bitumens atvarious maturities by catalytic hydropyrolysisLiao, Y. et al. Organic Geochemistry , 2012, 46, 5665.Solid bitumen occurs extensively in the paleo-reservoirs of marinesequences in southern China. The fluids in these paleo-reservoirs have

usually experienced severe secondary alteration such as biodegradationand/or thermal maturation. The concentrations of extractable organicmatter (EOM) in the resulting solid bitumens are too low to satisfy theamount required for instrumental analysis such as GCMS and GCIRMS. It is also difficult to get enough biomarkers and n-alkanes by drypyrolysis or hydrous pyrolysis directly because such solid bitumens arehydrogen poor due to high maturities. Catalytic hydropyrolysis (HyPy)can release much more EOM from solid bitumen at mature to highlyover-mature stages than Soxhlet extraction, dry pyrolysis and hydrouspyrolysis. However, whether the biomarkers in hydropyrolysates can beused for bitumen-source or bitumenbitumen correlations has beenquestionable. In this study, a soft biodegraded solid bitumen sample oflow maturity was thermally altered to various maturities in a closedsystem. HyPy was then employed to release bound biomarkers and n -alkanes. The results show that the geochemical parameters for sourceand maturity based on biomarkers released from these thermallyaltered bitumen residues by HyPy are insensitive to the degree ofthermal alteration. Furthermore, the maturity parameters are indica-tive of lower maturity than bitumen maturation products at a corres-ponding temperature. This suggests that biomarker source and

maturity parameters, based on the products of HyPy, remain validfor bitumens which have suffered both biodegradation and severethermal maturation. The distributions of 13C of n-alkanes in hydro-pyrolysates are also insensitive to the temperature used for bitumenartificial maturation. Hence, the 13C values of n-alkanes in hydro-pyrolysates may also provide useful information in bitumenbitumencorrelation for paleo-reservoir solid bitumens.

13/00008 Variations in the mechanical behavior of Illinoisbituminous coalsWest, R. D. et al. Fuel, 2012, 98, 213217.Unmineable coal beds are being considered as one of the geologicalsequestration options for storing carbon dioxide (CO2). The storagemechanisms and potential risks associated with the effects of CO 2 on

the coal structure are not yet understood and must be evaluated. Themechanical properties of the coal are expected to play an importantrole in the coal seams stability, especially under external pertur-bations. Typically, the mechanical characteristics of coal are investi-gated as a bulk material, which averages the effects of variousstructural inhomogeneities as well as of face and butt cleat fracturespresent in the coal. This paper establishes baseline mechanicalcharacteristics of Illinois bituminous coals while minimizing thefracture effects. Rectangular coal strips (length


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heterogeneous swelling, in combination with differential accessibility ofthe coal microstructure. No evidence was found that CO2-inducedplasticization of the macromolecular structure of the coal matrix playedany role in the behaviour observed. Simple mechanical considerationsindicate that at in situ stresses corresponding to a depth of 10001500m, i.e. effective stresses in the range 2535 MPa, adsorption-induced microfractures are unlikely to form. This means that improvedaccess of CO2 to coal matrix material for ECBM production canprobably be achieved only by inducing damage into coal seams, eitherby injection of solvents/solutes, or by performing active mining of thecoal and/or the over- or underlying strata.

13/00011 Mineral transformations during high temperaturetreatment of anthraciteRodrigues, S. et al. International Journal of Coal Geology , 2012, 94,191200.SEM/EDX analysis has been applied in order to assess the miner-alogical transformations occurring during high temperature treatmentof several different anthracites. At 1000 C (carbonization) loss of CO2from carbonates, S from sulfides and OH and/or H2O from claysoccurs, transforming these minerals to other inorganic phases such aslime, pyrrhotite, and (Na, Mg) K-aluminosilicates, among others. Heattreatment of the carbonized samples up to 1500, 2000, and 2500 Cresulted in: (i) a decrease in oxygenated mineralogical phases, whichare transformed to higher temperature silicates (grossite, anorthite,kushiroite, etc.); (ii) carbide formation (SiC, TiC or Al4C3) bycarbothermal reactions; (iii) formation of alloys, especially a PbSnalloy; and (iv) formation of iron silicides (Fe2Si), iron phosphides(Fe3P), and nitrides (TiN and AlN). The new mineral phases areclosely related to the mineral matter in the raw anthracite samples.Thus, samples richer in CaMg phases (carbonates and phosphates)produced minerals such as monticellite, pyrope, gehlenite, grossite andkushiroite; samples richer in Al-bearing phases (boehmite anddiaspore) gave rise to phases such as mullite, corundum and spinel;and SiAl bearing phases (clay minerals) were associated with theformation of minerals such as panunzite, plagioclase and cristobalite.

At the highe st temper ature of the proces s t he majori ty of the elemen tsvapori zed, and Ti seems to be the only elemen t in the origi nal mine ralmatter that withstands treatment to 2500 C.

13/00012 Risk assessment of floor water inrush incoal mines based on secondary fuzzy comprehensiveevaluationWang, Y. et al. International Journal of Rock Mechanics and MiningSciences, 2012, 52, 5055.

A second ary fuzzy compr ehensi ve evalua tion system is constr ucted toevaluate the risk of floor water invasion in coal mines. Four first-gradeindices and 13 second-grade indices are determined based on theprinciples of scientificity, rationality, operability and representative by

using fuzzy mathematics theory. Each index is quantitatively gradedaccording to five risk grades using fuzzy statistical method and expertevaluation method, and the membership degree of every index isconstructed. The weight of every index is rationally distributed byanalytic hierarchy process. Evaluations of engineering practice arecarried through with hydrogeological data of six mining faces in China.The satisfying evaluation results are consistent with engineeringpractice.

13/00013 Stability analysis of the proposed hybrid methodof partial extraction for underground coal miningJaiswal, A. and Shrivastva, B. K. International Journal of RockMechanics and Mining Sciences, 2012, 52, 103111.The hybrid method of partial extraction from underground coal mineshas been proposed for better recovery without endangering the surfacefeatures. The concept of panel stability, rather than pillar stability, hasbeen suggested for stability analysis of proposed method of partialextraction. The methodology for assessing the panel stability is basedon the Salamon stability criterion along with pillar stability. It has been

outlined as: factor of safety should be more than two for larger pillars,and more than one for smaller pillars; panel factor of safety should bepreferably more than two. Panel factor of safety, KLMS/KC, is definedas a ratio of local mine stiffness,KLMS, and post failure stiffness of thesplit coal pillars, KC. A worst-case scenario analysis has also beensuggested as a part of stability analysis by considering failure of splitpillars. A typical case study of the board and pillar system of mininghas been chosen to evaluate the applicability of proposed hybridmethod of partial extraction. It has a major sub-surface feature ofperennial stream. There are several pillars underlying this feature. Twovariations of hybrid method with galleries width of 7.0, 8.0 and 9.0mhave been taken. It has been concluded from the analysis that byadopting the hybrid method of partial extraction, coal productioncould be improved substantially without compromising the stability ofthe surface and underground structure.

13/00014 The role of surface interaction forces and mixingin enhanced dewatering of coal preparation tailingsOfori, P. et al. Fuel, 2012, 97, 262268.Industrial waste containing colloidal particulate matter such as coaland mineral processing tailings presents many environmental andeconomic challenges. Effective management solutions for thesechallenges require an improved understanding of colloidal forcesbetween tailings particles which control their flocculation andsubsequent dewatering. In this paper, the colloidal and dewateringbehaviours of four coal processing tailings were investigated in thepresence of four high molecular weight anionic polyelectrolytes usingthe AFM (atomic force microscope) colloid probe technique, floccula-tion and sedimentation testing, and colloid and surface characteriz-ation. Averaged snap-off distances statistically determined fromthousands of force curves measured by AFM were obtained by dividingthe area between the force curve and the horizontal axis by themaximum adhesion force. This novel assessment of the AFM resultsshowed that for each of the tailing samples and flocculants tested there

was statis tical ly a maxim um snap-of f dista nce, which on average wouldcorrespond to the optimum flocculant concentration. Under thisoptimum concentration condition the adhesive strength is the strongestto resist potential floc breakage caused by external hydrodynamicforces. Flocculation and sedimentation tests also showed optimumflocculant concentrations for the different tailings samples but theseconcentrations were much higher than those corresponding to theoptimum adhesive strength found with the AFM measurements. This

was due to the large surfa ce area of parti cles in the concen tratedsuspension used in the settling tests compared with just a few particlesused in the atomic force measurement and therefore the two optimumconcentrations per unit surface area of particles would be similar.

Transport, storage

13/00015 A novel method to suppress spontaneousignition of coal stockpiles in a coal storage yardKim, C. J. and Sohn, C. H. Fuel Processing Technology, 2012, 100,7383.Spontaneous ignition of coal stockpiles and its suppression in a coalstorage yard are studied numerically. The process of coal ignition issimulated with several physical and chemical properties. The mainpurposes of the numerical simulation are to pursue novel suppressionmethods and verify them. Without losing essential features ofspontaneous ignition, as simple numerical models as possible are used.The numerical approach is validated by comparison with theexperimental data. The ignition mechanism is analysed and essentialelements for ignition are pursued. Based on the ignition mechanism,

three new methods are proposed in this study. They are to adoptinternal walls installed inside the pile, air blowing from the bottom ofthe pile, and a dual barrier installed at the front and the rear of thepile. Each method has been verified to retard spontaneous ignitiontime more fundamentally than the existing methods and the expectedadditional delay is about 1030 days. But, air blowing is effective insuppression of spontaneous ignition only at higher rates than a criticalrate. More delay can be made by a combined application of thesemethods. It is found that the proposed methods are viable and effectivein delay of coal ignition.

13/00016 Risk and mitigation of self-heating andspontaneous combustion in underground coal storageSipila , J. et al. Journal of Loss Prevention in the Process Industries,2012, 25, (3), 617622.While the self-heating and spontaneous combustion of coal is a knownchallenge at coal mines and storage sites, there are known methods formitigating this challenge for typical open stockpile storage. However,closing the storage will reduce access for corrective action, and it is

then important to manage the storage and its transport system withadded attention without unduly adding cost or hindering availability.This paper aims to discuss the risk, prevention and extinguishing offires in closed coal storage facilities, particularly in light of theexperience with the Salmisaari underground rock storage facility inFinland. The observed autoignition events have indicated an array ofcontributing factors, some of which are unique to underground silostorage facilities. On the other hand, many features of the storagefacilities can be compared with other extant closed storage systems.The factors affecting fire risk are described and the associated fault andevent trees are outlined for autoignition at underground storage.Drawing upon the experiences with past events of self-heating andspontaneous combustion, recommendations are given on cost-effectivepreventive, corrective and other mitigating action for minimizing firerisk and promoting storage availability.


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Economics, business, marketing, policy

13/00017 An economic comparison assessment of ligniteand biomass IGCC power plantsTsakomakas, N. G.et al. Applied Thermal Engineering, 2012, 38, 2630.

An econom ic asses sment betwee n ligni te and bioma ss integr atedgasification combined cycle power plants (IGCC and BIGCC respect-ively) for power generation was carried out. The two alternative powerplants are presented together with the selection of the appropriate

equipment. An economic evaluation was carried out for the two powerplants, taking into account a net power of 100MW. The economicevaluation was carried out using the methods of the net present valueand the internal rate of return. Finally, a sensitivity analysis was carriedout. Calculations have been carried out with an Excel spreadsheet. It

was shown that both invest ments are profit able throu ghout theireconomic life. However, because of the difference in the selling price ofthe MW h between the two power plants and to the cost of CO2emissions for the lignite power plant, the biomass plant is moreprofitable with a net present value up to e417 millions; and an internalrate of return of 23.33%. A threshold price of e27.28/t for CO2emissions was also determined.

13/00018 In situ stress field inversion and its application inmining-induced rock mass movementZhao, H. et al. International Journal of Rock Mechanics and MiningSciences, 2012, 53, 120128.Based on a series of experiments in numerical simulation, the modelboundary conditions for in situ stress field inversion and excavation are

discussed. Study results indicate that roller boundary conditions arereasonable for the in situ stress field inversion before excavationsimulation, while, as a closed system, changing the roller boundaryconditions to fixed boundary conditions in the subsequent excavation isoptimal when the dimensions of the model borders are greater enoughthan the zone of influence of the excavation. As a case study, acomparative study of the mining-induced ground movement in asteeply dipping mine is carried out in two different stress fields. Theresults show that the mining-induced ground movement in the high-level tectonic stress field clearly differs from that in the ideal self-weightstress field. Because of the steep occurrence and large thickness of theore body, the mining-induced ground subsidence exhibits differentcharacteristics at different mining stages in the practical tectonicenvironment. Further studies elucidate the causes of these differencesand clarify the effects of high-level tectonic stresses on rock massmovement and deformation. Finally, based on GPS monitoring resultson the ground surface, the current ground subsidence is evaluated andits development trend is predicted.

13/00019 International coal trade and restrictions on coal

consumptionRiker, D. A. Energy Economics, 2012, 34, (4), 12441249.Coal consumption is a major source of CO2 emissions and other airpollutants and is therefore a focus of environmental policy. However,countries that restrict their coal consumption will likely expand theircoal exports to foreign markets with fewer restrictions on consumption.The adjustment in international trade will mitigate the impact on coalindustry employment but will also reverse some of the reduction inglobal emissions. This paper quantifies the impact of restrictions oncoal consumption in the USA and several other large countries onglobal coal consumption, trade, and industry employment. The impactcalculations are based on an econometric model of the internationalcoal market. The parameters of the model are fitted to panel data oncoal consumption and production in 53 countries. Efforts to limit acountrys coal consumption will, to some extent, reduce the countryscoal industry employment. International coal trade determines therelative magnitude of these adjustments. The basic trade-off betweencoal consumption and industry employment will shift as more countries

join in reduc ing coal consu mptio n. If more countr ies restr ict their coalconsumption, then leakage will be reduced, but the negative impact on

coal production and industry employment will be magnified.

13/00020 Looking for hysteresis in coal consumption inthe USCongregado, E.et al. Renewable and Sustainable Energy Reviews , 2012,16, (5), 33393343.This paper estimated unobserved components models for coal con-sumption in the USA. Defining hysteresis in terms of the interdepen-dent evolution of a non-stationary natural component and a stationarycyclical component, thereby distinguishing hysteresis from naturalcomponent shocks, the results provide robust evidence of hysteresis,although the hysteresis coefficient is time varying. This implies thatpolicy shocks in have permanent effects on coal consumption, although

with differ ent inten sity depend ing on the regim e. Futur e work might

fruitfully apply the methodology used in this article to a broader rangeof energy sources and revisiting the robustness of some previousstudies on energy consumption.

13/00021 Recovery and utilization of waste heat in a coalbased sponge iron processKumar, V. and Khanam, S. Chemical Engineering and Processing:Process Intensification, 2012, 56, 1928.The present work is an attempt to conserve energy in coal-basedsponge iron industry incorporating certain design modifications with-out disturbing the process technology. A typical sponge iron plant has

been investigated to find out the potential areas where energy is beingwasted . To recover heat from these areas two desig n modifi cation s,case-1 and case-2, are proposed. Case-1 accounts for preheating of airusing waste gas exiting from ESP. However, for case-2 initially water isheated using hot sponge iron exiting rotary kiln and further hot water isused to preheat air. To compute coal demand of modified designs amodel is developed based on heat of reactions, feed preheating,sensible and radiation losses, etc. Preheating of air up to 170 C forcase-1 reduces coal consumption by 8.7%. Consequently, waste gasgeneration reduces by 16.7%. Thus, for case-1 profit is Rs 9.6 million/

year. However , f or c ase-2 prehea ting of a ir to 8 0 C before entering thekiln reduces coal and water consumption by 7.2% and 96.3%.Consequently, cooling tower capacity is reduced by 37.2%. Due to27.8% less profit for case-1 in comparison to case-2, case-1 offershigher payback period than that of case-2. Thus, case-2 is selected asbest proposed design.

13/00022 Thermoeconomic operation optimization of acoal-fired power plantXiong, J. et al. Energy, 2012, 42, (1), 486496.

Thermoeconomic models, which combine the concept of cost in thefield of economics and the concept of exergy in the field of thermo-dynamics, provide a possibility of optimizing complex energy-generat-ing systems to achieve a best balance between thermodynamicefficiency and economic cost (including investment cost and operationcost). For the first time, operation optimization on a 300 MW coal-firedpower plant located in Yiyang (Hunan Province, China) is accom-plished based on the structure theory of thermoeconomics. Twooptimization strategies, global optimization and local optimization,are successively realized on the power plant. Both strategies aim tominimize the total annual cost of the plant, and a 2.5% reduction in thetotal annual cost and a 3.5% reduction in the total investment cost areachieved. In addition, the costs of products of almost all units afteroptimization processes decrease obviously. It is worth noting that localoptimization proposed in this paper attains almost the same perform-ance as global optimization but with faster speed. Furthermore, sen-sitivities of optimal operation parameters with respect to externalenvironmental parameters and the sensitivity of the objective function(the total annual cost) with respect to decision variables (e.g. theequipment efficiency) are presented.

13/00023 Underground coal-air gasification based solidoxide fuel cell systemPrabu, V. and Jayanti, S. Applied Energy, 2012, 94, 406414.Underground coal gasification (UCG) is a potential clean coaltechnology which converts coal into combustible gas in situ. The syngasproduced from the UCG process using dry air contains more steam, tarand higher hydrocarbons compared to the conventional gasifiers. Thefocus of the present work is to use solid oxide fuel cells (SOFCs) toproduce electrical power efficiently. To this end, a UCG system, basedon air alone as the gasifying medium, is integrated with the SOFCsystem taking advantage of the high temperature exhaust from thelatter to reform the syngas for producing hydrogen. Additional power isproduced in the conventional way from a steam turbine making use ofthe unused fuel in SOFC. A detailed energy analysis of this systemshows more than 4% thermal efficiency gain over an electricitygenerating system based entirely on a steam turbine cycle.

Derived solid fuels

13/00024 Co-catalytic effect of sewage sludge-derived charas the support of Fenton-like catalystTu, Y. et al. Chemical Engineering Journal, 2012, 185186, 4451.Sewage sludge-derived char was successfully employed as the supportof heterogeneous Fenton-like catalyst for the first time. Physicochem-ical properties of the prepared sewage sludge-derived char supportediron oxide catalyst (FeSC) have been evaluated by XRD, SEM, EDSand N2-adsorption/desorption analysis. FeSC exhibited better perform-ance in discoloration of AOII than wood sawdust-based carbonsupported iron oxide catalyst (FeWC) both in batch experiment and

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continuous tests. The high inorganic components content of sewagesludge was concluded to have strong correlations with the high catalyticactivity of FeSC. To further interpret the co-catalytic effect ofinorganic components in sewage sludge, the inorganic components

were removed from the sewage sludg e and then a series of cataly stswere prepar ed by the additi on of iron, as well as sili ca and/or alumi nato the sewage sludge free of the inorganic components. It was foundthat the removal of inorganic fraction remarkably decreased thecatalytic activity of iron-containing catalyst. The insertion of SiO2favours the increase in catalytic activity due to the formation of bothhydrogen bonds between H2O2 and siloxane bridges and the acidicmicroenvironment near the surface of silica phase. While the additionof Al2O3in sewage sludge as basic sites can facilitate the degradation ofH2O2, and the characteristic of Lewis acidity of alumina can acceleratethe reduction of Fe3+ to Fe2+ by H2O2.

13/00025 Flow behaviour of slags from coal and petroleumcoke blendsDuchesne, M. A. et al. Fuel, 2012, 97, 321328.Petroleum coke may be used as a fuel for entrained-flow slagginggasification. It may be blended with coal to provide a more attractivefeedstock. The coal provides the benefits of enhancing reactivity andincreasing the amount of slag coating the gasifier walls, while thepetroleum coke increases the heating value of the fuel blend. Theslagging behaviour of the petroleum coke or blend must be known todetermine if it is a suitable feedstock. In the present study, the slag

viscos ities of coal, petrol eum coke and coal/ petrol eum coke blend swere measur ed in the temper ature range of 1175 1650 C. Twodifferent viscosity measurement apparatuses were used in separatelaboratories. Some viscosity measurements were repeated to testreproducibility of the results. Also, slags with and without sulfur were

tested to determine whether the effect of sulfur can be neglected. Thelargest deviation between repeated log (viscosity in Pa s) measurementsis 0.11. Both petroleum coke slags tested are suitable for operation ator above 1275 C. The temperature range of operability for one coalslag tested increased when blended with petroleum coke ash, but didnot significantly change for other coal slags tested. Some effects ofblending on viscosity behaviour can be explained by network formerand modifier theory. Other effects are attributed to solids formation

which was invest igate d via slag quench ing exper iments and FactSa gepredictions. Below 1300 C, vanadium, a major component of pet-roleum coke ashes, promotes the formation of spinel which increasesslag viscosity.

13/00026 In situcharacterization of structural changes andthe fraction of aligned carbon nanotube networks producedby stretchingLi, S. et al. Carbon, 2012, 50, (10), 38593867.The mechanism of carbon nanotube (CNT) alignment during stretch-ing was examined by the in situ characterization of carbon nanotube

networks (CNTNs) under tensile strains using X-ray and Ramanscattering techniques. A method of quantifying the inhomogeneousalignment of macroscopic CNTNs is explored based on bulk propertymeasurements of their electrical anisotropy and X-ray diffractiondiagrams. The results show that the process of stretch-inducedalignment of CNTNs included straightening the waviness of the longnanotube ropes, as well as the self-assembling and denser packing ofthe nanotubes. For samples at a strain of 40%, the fraction of alignednanotubes was as high as 0.85. The aligned fraction of CNTs serves asan important parameter for the quality control of the alignmentprocess and numerical simulations of structureproperty relationshipsof CNTNs and their composites.

13/00027 Influence of nanotube characteristics onelectrical and thermal properties of MWCNT/polyamide 6,6composites prepared by melt mixingCaa mano , C. et al. Carbon, 2012, 50, (10), 36943707.Differential scanning calorimetry, X-ray diffraction, dynamic mechan-ical analysis (DMA) and electrical conductivity measurements were

performed on multiwalled carbon nanotube/polyamide 6,6 compositeswith four differ ent types of well-c haract erize d tubes manufa cture dusing fixed-bed catalytic processes. The tubes differed in diameter,number of walls and surface chemistry. Except for one very poorlyformed set of tubes, there were not large differences in behaviour withrespect to modulus, maximum electrical conductivity and percolationthreshold; none of which differed by more than a factor of two for thethree types of tubes. However, the shape of the percolation region was

very differ ent for the larger diame ter tubes in that the perco lationregion occurred over a much wider concentration. Glass transition andcrystallization/melting characteristics also showed very small differ-ences between the three types of tubes. One unique observation madein this work was that the glass transition temperature (Tg) showed aqualitatively different behaviour depending on what was used tomeasure the transition: DSC indicated an increase in Tg with added

nanotubes while DMA showed a decrease in Tg. Other than thedifference being related to how the Tg was measured, it is not clearwhat caused the qualitatively different behaviour.

13/00028 Lignin as both fuel and fusing binder inbriquetted anthracite fines for foundry coke substituteLumadue, M. R. et al. Fuel, 2012, 97, 869875.Lignin that had been extracted from kraft black liquor was investigatedas a fusing binder in briquetted anthracite fines for a foundry cokesubstitute. Cupola heat zone pyrolytic temperatures of 3001550 C

were appra ised, with the focus on 900 C. Briquettes with favourable

strength were made with 8692% anthracite fines, 2.38.6% lignin,4.5% silicon metal powder, and 0.9% hydrolysed collagen (denaturedcollagen) by mass. Briquettes were pyrolysed under a nitrogenatmosphere or a starved air condition to simulate a cupola pyrolyticheat zone, and then crushed after this pyrolysis so as to discern theirunconfined compressive (UC) strength. These tests mimicked keyfeatures of the crushing load that coke endures in a cupola. After30min of 900 C pyrolysis, UC strength reached 22003000kPa (320440 psi), when these briquettes contained 4.5% softwood lignin or 2.3%hardwood lignin. With 6.5% hardwood lignin, the UC strength after900 C pyrolysis reached 60006500 kPa. When no lignin was incor-porated into the briquette, the UC strength after 900 C pyrolysis was amere 200 kPa. Denatured collagen quantity affected lignin heat zonestrength, despite by itself losing strength around 300 C: with 4.5%lignin present, 1.8% denatured collagen doubled the strength of 0.45%denatured collagen briquettes. Adding tannic acid to the briquettesgreatly increased the UC strength as well. Lignin provided strength upto 1400 C. Moreover above 1100 C, silicon carbide nanowires greatlyenhanced UC strength relative to lignin alone. Briquettes with ligningained UC strength very quickly when flash pyrolysed to 900 C, which

is important in the cupola. The results herein showed that the binderedbriquettes burned at an equal rate as did coke when these were burnedat 1100 C in air. The briquettes also contained an energy density that

was 38% highe r by volume than that of coke. Harnes sing these hightemperature pyrolytic lignin fusing reactions creates a valuable foundrycoke substitute for the future, as well as large scale applications forotherwise underutilized industrial streams of lignin.

13/00029 On the use of single-film models to describe theoxy-fuel combustion of pulverized coal charGeier, M. et al. Applied Energy, 2012, 93, 675679.Computational fluid dynamic (CFD) simulations traditionally rely onthe computational efficiency of single-film global kinetic oxidationmodels to predict char particle temperatures and char conversion ratesin pulverized coal boilers. In oxy-fuel combustion with flue gasrecirculation (FGR), as is commonly employed, char combustionoccurs in the presence of elevated CO2 levels and, frequently, elevated

water vapour levels (when empl oying wet FGR). Furth ermor e, localoxygen concentrations can be quite high in the vicinity of oxygeninjection lances. The suitability of existing approaches to modelling

char combustion under these conditions has been unclear. Inparticular, the authors previous work has shown that both boundarylayer conversion of CO and gasification reactions of steam and CO 2need to be included to give reasonable agreement with the experimen-tal measurements, for particles over 60 mm in size. This paper reportson the development and application of an extended single-film reactionmodel that includes both oxidation and gasification reactions. Theauthors have systematically interrogated the performance of the modelin comparison to experimental data for two US coals (a Powder RiverBasin subbituminous coal and a low-sulfur, high-volatile bituminouscoal) for a variety of model assumptions. While the extended single-film model does not give perfect agreement with the data, reasonablygood agreement is achieved for high-temperature environments with1236 vol.% O2 and 16 vol.% H2O in either N2 or CO2 diluent. Theanalysis shows that, to achieve such agreement with the data whilemaintaining reasonable values for activation energy of the reactions,incorporation of both steam and CO2gasification reactions is required.

13/00030 Pore pressure changes accompanying exchange

sorption of CO2/CH4 in a coal briquetteDutka, B. et al. Fuel Processing Technology, 2012, 100, 3034.The paper presents the study of CO2/CH4 exchange sorption in a coalbriquette. The briquette was formed inside a heavy-walled steel pipethat served the purpose of a measuring chamber. The briquette with aporosity of 8.3%, a diameter of 0.096m and a length of 0.280m wasused. Three laboratory experiments were conducted. The experimentsconsisted in CO2 injecting onto the input of the briquette previouslysaturated with CH4. In each experiment, during the exchange sorptionprocess, the input CO2pressure and output gas mixture pressure werestabilized at the level of 11, 12 and 13 bar at the input and 10 bar at theoutput of the briquette. Pressure changes along the briquette andconcentration of the gas mixture flowing out of the briquette wereanalysed. It was observed that a pore pressure depression moving alongthe briquette accompanies the exchange sorption. The presence of the


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pore pressure depression indicated existence of a separated zone whereexchange sorption takes place. It was also observed that from themoment that CO2 appeared at the output of the briquette, suddenchanges of its concentration were recorded. This phenomenonconfirms the thesis of the exchange zone occurrence accompanyingthe CO2/CH4exchange sorption in the briquette. A description methodof the observed phenomenon was proposed.

13/00031 The effect of additives on coking pressure andcoke qualityFernandez, A. M. et al. Fuel, 2012, 95, 642647.

An indus trial coal blend (ICB ) normal ly used in cokem aking wasselected for the study. A coal that is known to produce high cokingpressure was added to the industrial coal blend in two percentages, i.e.20 and 25 wt%. To reduce the coking pressure generated due to theaddition of the dangerous coal to the ICB, two coals of different ranknormally used in the process of pulverized coal injection (PCI) in blastfurnaces and coke fines were used as additives. The pressure exertedon the oven wall was measured by carbonizing the blends in a 17 kgelectrically heated movable wall oven. In addition, the permeability ofthe coal plastic layer was assessed. The quality of the cokes produced

was evaluat ed by measur ing their cold mechan ical stren gth, reacti vityand post-reaction strength. It was found that, although coke fines arethe most effective additive in reducing coking pressure, they causeconsiderable impairment to coke quality. On the other hand, the low

volati le PCI coal succe ssful ly reduc es cokin g press ure withou t causi ngany great impairment to coke quality.

02 LIQUID FUELS

Sources, properties, recovery

13/00032 A quasi-discrete model for droplet heating andevaporation: application to diesel and gasoline fuelsElwardany, A. E. and Sazhin, S. S. Fuel, 2012, 97, 685694.The previously suggested quasi-discrete model for heating andevaporation of complex multi-component hydrocarbon fuel dropletsis generalized to take into account the dependence of density, viscosity,heat capacity and thermal conductivity of the liquid components oncarbon numbers and temperature. This model is applied to themodelling of heating and evaporation of diesel and gasoline fueldroplets. In agreement with the prediction of the previously reportedsimplified version of this model in which density, viscosity, heat capa-city and thermal conductivity of all liquid components were assumed tobe the same as for n-dodecane, it is pointed out that diesel fuel dropletsurface temperatures and radii, predicted by a rigorous model takinginto account the effect of all 20 quasi-components, are almost the sameas those predicted by the model using five quasi-components. For theeffective thermal conductivity/effective diffusivity (ETC/ED) model,the number of quasi-components used can be reduced to three. In thecase of gasoline fuel, with the maximal number of quasi-componentsequal to 13, a good approximation for the ETC/ED model can beachieved based on the analysis of just three components. The differ-ence in predictions of the 13 and 1 component models appears to beparticularly important when droplets evaporate in gas at a relativelylow temperature (450 K) and low pressure (0.3 MPa). In this case theevaporation time predicted by the one component model is less thanhalf of the time predicted by the 13 component model. The surfacemass fraction of the lightest quasi-component in gasoline fuel mono-tonically decreases with time, while the surface mass fraction of theheaviest component monotonically increases with time. Surface massfractions of intermediate components initially increase with time, but atlater times they rapidly decrease with time.

13/00033 A shock tube and chemical kinetic modelingstudy of the pyrolysis and oxidation of butanolsYasunaga, K. et al. Combustion and Flame, 2012, 159, (6), 20092027.The pyrolysis and oxidation of all four butanols (n-butanol, sec-butanol, iso-butanol and tert-butanol) have been studied at pressuresfrom 1 to 4 atm and temperatures of 10001800 K behind reflectedshock waves. Gas chromatographic sampling at different reaction timesvarying from 1.5 to 3.1 ms was used to measure reactant, intermediateand product species profiles in a single-pulse shock tube. In addition,ignition delays were determined at an average reflected shock pressureof 3.5 atm at temperatures from 1250 to 1800K. A detailed chemicalkinetic model consisting of 1892 reactions involving 284 species wasconstructed and tested against species profiles and ignition delays. The

little-known chemistry of enols is included to explain the temperaturedependence of acetaldehyde produced in the thermal decomposition ofisobutanol.

13/00034 Ammonia-treated brown coal and its activity foroxygen reduction reaction in polymer electrolyte fuel cellMuraoka, M. et al. Fuel, 2012, 97, 211218.Coal has been utilized as a non-precious metal catalyst for the oxygenreduction reaction (ORR) in a polymer electrolyte fuel cell. The

Austr alia brown coal was nitro gen-dop ed at 6731 123 K in a strea m ofNH3. The raw and NH3-treated Australia brown coals were character-

ized on the basis of their N2 adsorption, Raman spectroscopy and X-ray photoelectron spectroscopy. The nitrogen doping of the coal at1073 K increased the BET surface area from 10 to 671 m2/g h aving 95%slit-shaped micropores with a type I monolayer adsorption. Thenitrogen-doped coal at 1073 K exhibited the highest potential of0.85V vs RHE (at 0.005 mA/cm2), which was evaluated by three-electrode electrochemical measurements using a rotating ring diskelectrode in a 0.5 M H2SO4aqueous solution. The ORR activity of thenitrogen-doped coal was related to the pyridine-N species, micro-porosity and degree of disordered carbons in the coal. The ironaddition to the coal from 10 to 10 3 ppm increased the ORR onsetpotential. The active structure of the coal-derived catalyst wasdiscussed based on the results of the XPS, Raman, N2 adsorptionand iron effect.

13/00035 Artificial bacterial degradation and hydrouspyrolysis of suberin: implications for hydrocarbongeneration of suberiniteYao, S. et al. Organic Geochemistry, 2012, 47, 2233.The organic maceral suberinite is widely believed to be a contributor to

immature or low mature oils with Ro 0.5%,has not been sufficiently characterized. This issue was addressed hereinusing periderm cork tissues of the modern angiosperm Quercus suber(suberin), which is a possible bio-precursor of suberinite, in artificialbacterial degradation and hydrous pyrolysis experiments. Integratedstudies were conducted, including analyses on the compositions ofhydrocarbon yields and the content variations that were generatedduring the experiments, gas chromatography (GC) analyses ofgenerated oils and spectral fluorescence observations, and Rock-Evaland Fourier transform infrared microspectroscopic studies on solidresidues. Analytical results indicate that suberin and suberinite havelong and complex hydrocarbon generation histories. In general, thehydrocarbon that is generated during bacterial degradation ispredominantly gas and present in relatively limited amounts, whilethe oils mainly are generated during hydrous pyrolysis. Furthermore,the oil generation has two peaks that correspond to Ro of approxi-mately 0.350.50% and 0.801.10%. In composition, the early gen-erated oil mainly consists of long chain waxy and oxygen containing

compounds, while the late generated oil is relatively enriched inaromatic compounds. These features can be ascribed to the chemicalnature (e.g. composition and structure) of suberin. It is a type ofinsoluble and high molecular weight polyester compound that containslarge quantities of long chain structure dicarboxylic acids and alcohols.Consequently, the deoxygenization of these compounds can take placeunder relatively low thermodynamic conditions, generating liquid oilthat is dominated by a long chain structure and oxygen-containingwaxy compounds. In contrast, the degradation of the phenolic com-pounds results in the second oil generation peak. Therefore, suberinitehas a two stage and relatively long oil generation history and is a goodbio-precursor for coal-derived oil generation.

13/00036 Biomarkers in crude oil revealed bycomprehensive two-dimensional gas chromatography time-of-flight mass spectrometry: depositional paleoenvironmentproxiesOliveira, C. R. et al. Organic Geochemistry, 2012, 46, 154164.Crude oil samples from two basins were analysed using comprehensive

two-dimensional gas chromatography coupled to time-of-flight massspectrometry (GCGCTOFMS) to better understand the compo-sitional heterogeneity of branched-cyclic hydrocarbons. GCGCTOFMS and conventional GCMS results were compared. GCGCTOFMS revealed a wide range of compounds, including tricyclic,tetracyclic and pentacyclic terpane series, rearranged hopanes, methylhopanes, secohopanes, onoceranes and steranes. Assignment of methylhopane and 8,14-secohopane series other than onocerane isomers wasonly possible due to the high peak capacity and sensitivity of GCGC.The oils comprised a mixture of two end members: non-biodegraded oil

with abund ant tricy clic terpan es and hopane s, and severe ly biode-graded oil with abundant 8,14-secohopane and demethylated tricyclicterpanes. A predominance of two distinct series, 3-methylhopane andonocerane, was detected only in the lacustrine samples (classificationbased on biomarker parameters). In contrast, the predominance of a


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2-methylhopane series and lack of onocerane were found only for themarine oil sample. The results suggest that the distribution of 3- and2-methylhopane series and the presence or absence of onoceraneisomers reflect genetic differences in the source organic matter andthat these compounds are new classes of biomarkers that can used asdepositional paleoenvironment proxies.

13/00037 Burning rates of liquid fuels in fire whirlsLei, J. et al. Combustion and Flame, 2012, 159, (6), 21042114.This paper presents semi-empirical investigations on the quasi-steadyburning rates of laminar and turbulent fire whirls established over

liquid fuel pools. The inflow boundary layer above the fuel surfaceconsists of two regions: outer reactive region and inner non-reactiveregion. Based on the momentum boundary layer solutions with theapplications of stagnant film model and ChiltonColburn analogy, theburning rates are correlated with ambient circulation and pool size forlaminar and turbulent fire whirls respectively. It is shown that ingeneral pool fires the mass and heat transfers on the fuel surface arecontrolled by natural convection, while in fire whirls they are stronglyenhanced by forced convection. Fuel evaporation rate in the outerregion is relatively larger than that in the inner region. The largeproportion of fuel evaporated from the outer region is mainly due to itslarger area. The predictions agree well with the data from the presentexperiments and the literature. Furthermore, the flame height isconfirmed to be proportional to the ambient circulation for bothlaminar and turbulent liquid fire whirls.

13/00038 Classification of gasoline brand and origin byRaman spectroscopy and a novel R-weighted LSSVMalgorithmLi, S. and Dai, L.-k. Fuel, 2012, 96, 146152.

Raman spectroscopy, which is a kind of non-invasive measurementtechnique and the precise molecule fingerprint, has been widelyapplied to provide information on chemical structures and physicalforms, making it possible to be used for substance classification inqualitative analysis. This study classifies Raman spectra of 128 gasolinesamples which are provided by three different refineries and belong tothree different brands (90#, 93# and 97#). Since samples are partlyoverlapped in the principal component space, traditional classificationalgorithms based on principal component analysis (PCA) cannot beeffective. Least squares support vector machine (LSSVM) with the

whole spect ral range is introd uced. Moreover , a novel local weight edLSSVM algorithm is proposed to improve the classification accuracy.The weight is constructed based on correlation coefficient R and thisalgorithm can be denoted as R-weighted LSSVM. In this algorithm,both of Euclidean distance and correlation coefficient are considered toselect neighbouring samples. LDA based on PCA, LSSVM, localLSSVM and R-weighted LSSVM are compared in the classificationexperiment. Experimental results show that Raman spectroscopy is aneffective means to classify gasoline brand and origin, and the R-weighted LSSVM algorithm gives the best classification result.

13/00039 Determination of octane numbers in gasoline bydistillation curves and partial least squares regressionMendes, G. et al. Fuel, 2012, 97, 131136.In this work, distillation curves (ASTM D86) associated with multi-

variate calib ration (PLS-p artia l least squar es) were used to predi ctMON (motor octane number) and RON (research octane number)parameters of automotive fuel RMSEC getting values (root meansquare error of calibration) and RMSEP (root mean square error ofprediction) smaller than the literature. RMSECvalues obtained were0.051 and 0.078, and RMSEP values were 0.063 and 0.085 for MONand RON, respectively. These low values along with high accuracy,when compared to standard test methods (ASTM D2700 and ASTMD2999), indicated that the PLS models were efficient to predict MONand RON values and can be used as an alternative to control qualityfor automotive gasoline.

13/00040 Evolution of petrophysical properties of oilshales during high-temperature compaction tests:

implications for petroleum expulsionEseme, E. et al. Marine and Petroleum Geology, 2012, 31, (1), 110124.The transport properties of Permian to Miocene oil shales (Torbanite,Posidonia, Messel, Himmetoglu, and Condor) were studied usingpetrophysical and geochemical techniques. The aims of this study wereto assess permeability of oil shales, evaluate the evolution of porosity,specific surface area and intergranular permeability during hightemperature compaction tests and to verify the suitability of inter-granular permeability for petroleum expulsion. Measured permeabilitycoefficients for two samples were 0.72 1021 m2 for the EoceneMessel shale and 2.63 1021 m2 for the Lower Jurassic Posidoniashale from south Germany, respectively. BET specific surface areas ofthe original samples ranged from 0.7 to 10.6 m2/g and decrea sed aftercompaction to values from 0.3 to 3.7 m2/g. Initi al p orosit y val ues rangedfrom 7.6 to 20.1% for pre-deformation and from 9.99 to 20.7% for

post-deformation samples. Porosity increased during the high-tem-perature compaction experiments due to petroleum generation andexpulsion. Permeability coefficients estimated using the KozenyCarman equation varied from 6.97 1024 to 5.22 1021 m2 for pre-deformation and from 0.2 1021 to 4.8 1021 m2 for post-defor-mation samples reflecting the evolution of their porosity and BETspecific surface areas. Measured and calculated permeability weresimilar for the Messel shale whereas calculated permeability was twoorders of magnitude lower for the Posidonia shale from southGermany. Petroleum expulsion efficiencies under the experimentalconditions ranged from 38.6% for the Torbanite to 96.2% for thePosidonia shale from south Germany. They showed strong positivecorrelation with the petroleum generation index (R2 = 0.91) and poorcorrelations with porosity (R2 = 0.46), average pore throat diameters(R2 = 0.22), and compaction (R2 = 0.02). Estimated minimum pore-system saturations for petroleum expulsion during the experimentswere 12% for the Torbanite and 30% for the Posidonia shale fromnorth Germany. Pore-system saturation determines whether expulsionoccurs mainly through matrix or fracture permeability. For sampleswith saturation levels above 20%, fracture permeability dominatedduring the experiments. Evidence based on the measured permeabilitycoefficients, expulsion flow rates, consideration of capillary displace-ment during generation-related pore invasion and the existence oftransport porosity suggests that fracture permeability is the principalavenue of petroleum expulsion from source rocks. This conclusion issupported by microscopic observations.

13/00041 Geochemistry, origin and correlation of crude oilsin Lower Cretaceous sedimentary sequences of the southernMesopotamian Basin, southern Iraq

Abeed, Q. et al. Organic Geochemistry, 2012, 46, 113126.

Thirty-one crude oil samples from Lower Cretaceous reservoirs insouthern Iraq were analysed using bulk property and molecularmethods to determine their maturity and biomarker characteristics,as well as to obtain information on their respective source rocks. Allthe oils are unaltered, non-biodegraded, have high sulfur content and

API gravit y is in the range for light to heavy oil (194 0 API). They arecharacterized by low Pr/Ph values, even/odd predominance and front-end biased n -alkane distributions. Based on these parameters the oils

were genera ted and expel led from a marin e carbon ate sourc e rockbearing Type II-S kerogen. Compositional similarities of hopane andsterane biomarkers with those from potential source rocks allowedidentification of the Upper JurassicLower Cretaceous Sulaiy andYamama carbonate succession as the effective source beds. A similarcomposition of normal and isoprenoid hydrocarbons among the oilssuggests an origin from a common source rock. However, biomarkermaturity ratios indicate a wide range of maturity. This appears to resultfrom the type of burial history of the source rock, characterized by aslow passage through the liquid window interval during an extendedperiod of geologic time.

13/00042 Interfacial tension behavior of double long-chain1,3,5-triazine surfactants for enhanced oil recoveryQiao, W. et al. Fuel, 2012, 96, 220225.The paper is aimed at studying the influencing factors of producingultra-low interfacial tension (IFT) under alkali-free systems, includingmolecular structures as well as concentrations of double long-chain1,3,5-triazine surfactants (A-DCTn-8, n =8, 10, 12, 14), temperature,electrolyte, the property of oil phase, and mass ratios of surfactanthomologues mixtures. It was found that only A-DCT108 and A-DCT128 could reduce IFTs to ultra-low value (


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introduced into a combustor connected before the CFB furnace. Thesystem performance is simulated using ASPEN software tool in thispaper. The influence of retorting temperature, residence time,temperature and pressure of the CFB furnace, content of oil shalefor combustion, content of non-condensable gases for combustion onthe system performance are discussed. In order to explore advantagesof this system, a retort system and a combustion system areinvestigated. The results show that increasing retorting temperature,residence time, pressure of CFB furnace and content of non-condensable gases for combustion has positive significant effect onimproving the total profit and the output energy efficient of thecomprehensive utilization system. The solid heat carrier technology ismore adaptable for this system. Compared with other utilization modesfor oil shale, the comprehensive utilization system has higherutilization efficiency of oil shale resources, more diversified products,lower pollutants emission and higher total profit.

13/00044 Laboratory scale experimental analysis of steam-over-solvent injection in fractured reservoirs (SOS-FR) forheavy-oil recovery

Al-Bahl ani, A. M. and Babada gli, T. Journal of Petroleum Science andEngineering, 2012, 8485, 4256.Heavy oil trapped in fractured carbonate reservoirs possesses a greatchallenge to the petroleum industry due to high oil viscosity, low matrixpermeability, and unfavourable wettability of the matrix. Thermalrecovery methods (mainly steam injection) show a promising wayforward to unlock these reserves. Yet, previous experiences revealedthat heating the matrix to drain heavy-oil by gravity is a slow andinefficient process due to low matrix recovery caused by unfavourablematrix properties (oil wetness and low permeability). Acceleration ofmatrix-fracture interaction by changing the matrix and oil properties

could be possible by injecting the proper hydrocarbon solventalternately with steam as reported in earlier work. This process, calledsteam-over-solvent injection in fractured reservoirs (SOS-FR), consistsof several cycles, each having three phases: (1) steam/hot waterinjection; (2) solvent injection; and (3) steam/hot water injection. Thispaper reports a detailed experimental analysis of this new method.Static and dynamic tests were conducted by exposing heavy-oilsaturated fractured rocks to hot water and solvent alternately. Oil-

wet sands tone and carbon ate sampl es were satur ated with heavy-c rudeoil and tested against different solvents, namely heptane, kerosene,decane and light crude. Fractured cores were tested under dynamicconditions with different solvent injection rates to explore the ratedependency of the process. The physics of the injection rate and therole of asphaltene as a bi-product were examined and discussed.Understanding the physics of this new technique will contribute to thedevelopment of an alternative method at field conditions for unlockingtrapped heavy matrix oil from oil-wet, fractured, and deep carbonatefields.

13/00045 Oil exploration and perceptions of scarcity:

the fallacy of early successJakobsson, K. et al. Energy Economics, 2012, 34, (4), 12261233.It has been suggested that oil exploration may lead to false perceptionsof decreasing scarcity. This study performs a simulation of theexploration process using Bayesian updating. The approach isolatedthe information effect on the success rate and also quantified thesubjective expectation of the total resource size. The area underexploration consists of a number of regions which may differ in their oilcontent. Exploration is performed with the goal to maximize theexpected success rate. The resulting information about the distributionof oil and the total resource size is assumed public knowledge. Anumber of scenarios with variations in the dimensions of the areaunder exploration, the oil distribution and initial beliefs are con-sidered. The results indicate that the information effect on the successrate is significant but brief it might have a considerable impact onprice but is an unlikely mechanism behind a long-term declining pricetrend. However, the information effect on expectations is gradual andpersistent. Since exploration is performed in regions where theexpected success rate is the highest, the historical success rate willnot be representative of the area as a whole. An explorer will tend to

overestimate the total resource size, thereby suggesting an alternativemechanism for false perceptions of decreasing scarcity, a mechanismthat could be called the fallacy of early success.

13/00046 Petroleum generation and charge history of thenorthern Dongying Depression, Bohai Bay Basin, China:insight from integrated fluid inclusion analysis and basinmodellingGuo, X. et al. Marine and Petroleum Geology, 2012, 32, (1), 2135.The petroleum generation and charge history of the northern DongyingDepression, Bohai Bay Basin was investigated using an integrated fluidinclusion analysis workflow and geohistory modelling. One and two-dimensional basin modelling was performed to unravel the oilgeneration history of the Eocene Shahejie Formation (Es3 and Es4)

source rocks based on the reconstruction of the burial, thermal andmaturity history. Calibration of the model with thermal maturity andborehole temperature data using a rift basin heat flow model indicatesthat the upper interval of the Es4 source rocks began to generate oil ataround 35 Ma, reached a maturity level of 0.7% Ro at 3130Ma and apeak hydrocarbon generation at 2423Ma. The lower interval of theEs3 source rocks began to generate oil at around 3332Ma andreached a maturity of 0.7% Ro at about 2726Ma. Oil generation fromthe lower Es3 and upper Es4 source rocks occurred in three phases withthe first phase from approximately 3020 Ma; the second phase fromapproximately 205Ma; and the third phase from 5 Ma to the presentday. The first and third phases were the two predominant phases of

intense oil generation. Samples from the Es3 and Es4 reservoir intervalsin 12 wells at depth intervals between 2677.7 m and 4323.0m wereinvestigated using an integrated fluid inclusion workflow includingpetrography, fluorescence spectroscopy and microthermometry todetermine the petroleum charge history in the northern DongyingDepression. Abundant oil inclusions with a range of fluorescence col-ours from near yellow to near blue were observed and were interpretedto represent two episodes of hydrocarbon charge based on the fluidinclusion petrography, fluorescence spectroscopy and microthermome-try data. Two episodes of oil charge were determined at 2420Ma and43Ma, respectively with the second episode being the predominantperiod for the oil accumulation in the northern Dongying Depression.The oil charge occurred during or immediately after the modelledintense oil generation and coincided with a regional uplift and a rapidsubsidence, suggesting that the hydrocarbon migration from thealready overpressured source rocks may have been triggered by theregional uplift and rapid subsidence. The expelled oil was then chargedto the already established traps in the northern Dongying Depression.The proximal locations of the reservoirs to the generative kitchens andthe short oil migration distance facilitate the intimate relationship

between oil generation, migration and accumulation.

13/00047 Petroleum geochemistry of the Potwar Basin,Pakistan: II oil classification based on heterocyclic andpolycyclic aromatic hydrocarbons

Asif, M. and Fazeel at, T. Applied Geochemistry, 2012, 27, (8), 16551665.In a previous study, oils in the Potwar Basin (Upper Indus) of Pakistan

were corre lated based on the dissi milar ity of sourc e and deposi tionalenvironment of organic matter (OM) using biomarkers and bulk stableisotopes. This study is aimed at supporting the classification of PotwarBasin oils into three groups (A, B and C) using the distribution ofalkylnaphthalenes, alkylphenanthrenes, alkyldibenzothiophenes, alkyl-dibenzofurans, alkylfluorenes, alkylbiphenyls, triaromatic steroids,methyl triaromatic steroids, retene, methyl retenes and cadalene. Thehigher relative abundance of specific methyl isomers of naphthaleneand phenanthrene and the presence of diagnostic aromatic biomarkersclearly indicate the terrigenous and oxic depositional environment ofOM for group A oil. Group B and C oils are of marine origin and the

aforementioned heterocyclic and polycyclic aromatic hydrocarbons(HCs) differentiate them clearly into two different groups. The relativepercentages of heterocyclic aromatic HCs reveal that the distribution ofthese compounds is controlled by the depositional environment of theOM. Sulfur-containing heterocyclic aromatic HCs are higher in crudeoils generated from source rocks deposited in suboxic depositionalenvironments, while oxygen-containing heterocyclic aromatic HCs incombination with alkylfluorenes are higher in marine oxic and deltaicoils. Biomarker and aromatic HC parameters do not indicatesignificant differences in the thermal maturity of Potwar Basin oils.Triaromatic and methyl triaromatic steroids support the division ofPotwar Basin oils into the three groups and their relative abundancesare related to source OM rather than thermal maturity. Significantlyhigher amounts of C20 and C21 triaromtic steroids and the presence orabsence of long chain triaromatic steroids (C25, C26, C27, and C28)indicates that these compounds are probably formed from differentbiological precursors in each group. Different isomers of methylsubstituted triaromatic steroids are present only for short chaincompounds (C20C22) and the origin of these compounds may beshort chain methyl steranes from unknown biological precursors.

13/00048 Rock mechanics characteristic of complexformation and faster drilling techniques in western SouthChina Sea oilfieldsZhu, H. Y. et al. Ocean Engineering, 2012, 44, 3345.In order to increase the rate of penetration (ROP) and to reduce cost,the authors tested detritus for mineral components to study thelithological characters of the deep-sea complex formation of westernSouth China Sea oilfields. The prediction models of rock mechanicsparameters were established based on the experiments results of theuniaxial compressive strength (UCS), drillability, hardness, plasticityand abrasivity tests of cores sampled from the complex formation. Theyplotted profiles of rock mechanics parameters of 30 wells and threedimensional (3D) drillability planes using the log data to reveal the


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complex formations distribution and their rock mechanical properties.Then, the rock breaking mechanism of complex formation of cone andPDC bit are studied. According to rock mechanics characteristic ofcomplex formation and adjacent well drilling data, the authorsrecommend the bit structure, drilling methods and drilling parametersfor the northern Gulf Basin (NGB) and Pearl River Mouth Basin(PRMB) oilfields. The research results are used to guide the drilling

work of Z-10 91 and Z-11 18AS 1 well in the NGB and C-14 21well in the PRMB, compar ed with the adjace nt wells, the averagedrilling footage and ROP increase by 98% and 117.8%, respectively.

13/00049 The pyrolysis, extraction and kinetics of Buton oilsand bitumenMa, Y. and Li, S. Fuel Processing Technology, 2012, 100, 1115.In this paper, the pyrolysis and extraction experiments on Buton oilsand bitumen were carried out. The contents of oil, water, gas, andsemi-coke were determined and the pyrolysates were evaluated. Theaveraged oil content of Buton oil sand is about 20%. As measured byDeanStark toluene extraction, oil sand bitumen from Buton has theaveraged bitumen content of about 30%. Three kinds of solvents wereused to evaluate the bitumen recovery. The optimum conditions ofsolvent extraction were determined. The pyrolysates and bitumen wereanalysed. The pyrolysis kinetics of oil sand were performed using thedifferential scanning calorimetry at different heating rates of 15, 20, 25and 30 C/min. The kinetic parameters (apparent activation energy Eand frequency factor A) of oil sand pyrolysis were determined usingCoatsRedfern method. The value of apparent activation energy Ewasabout 20 kJmol1, corresponding to the conversion of 535%. Theapparent activation energy was nearly 40 kJmol1 while the conversionranges from 40% to 95%.

Transport, refining, quality, storage

13/00050 Deep desulfurization of gas oil over NiMocatalysts supported on aluminazirconia composites

Al-Dao us, M. A. and Ali, S. A. Fuel, 2012, 97, 662669.A series of NiMo cataly sts suppo rted on Al2O3ZrO2 compositescontaining 0, 2.5, 5 and 10 wt% ZrO2 was synthesized, characterizedand evaluated for deep desulfurization of gas oil. X-ray diffractionpatterns of the supports indicate homogenous dispersion of 2.510 wt%o f ZrO2 in bulk Al2O3. Mono-modal pore-size distribution wasobserved with a decrease in average pore-size with increasing ZrO2content. NH3-TPD results show that incorporation of 5 wt% or moreZrO2 neutralized the weak acid sites of Al2O3 and generated adifferent type of stronger acid sites. UVvisible diffuse reflectancespectroscopy results indicate the presence of tetrahedral and octahed-ral Mo6+ ions species along with an increase in octahedral species withaddition of ZrO2 possibly due to weaker interaction of active metalsand composite support. This result is also supported by H2-TPR andCO chemisorption measurements. Deep desulfurization of gas oil,carried out in a bench-scale flow reactor at 320, 340 and 360 C,indicate that the addition of ZrO2 increased the catalytic activity especially at higher temperature. Compared to Al2O3-based catalyst,the 1.5 order HDS rate constant was about 1.3, 1.8 and 2.5 times higherfor catalysts containing 2.5, 5 and 10wt% ZrO2, respectively. Acorrelation was found between the enhancement of hydrogenationactivity of sulfided catalysts and the reducibility of their oxide pre-cursors, as determined by the amount of hydrogen consumed in TPRexperiments followed by mass spectroscopy.

13/00051 Distribution of acids and nitrogen-containingcompounds in biodegraded oils of the Liaohe Basin bynegative ion ESI FT-ICR MSLiao, Y. et al. Organic Geochemistry , 2012, 47, 5165.Seven reservoir core (tar sand) bitumens of identical source and similarmaturity from the Liaohe Basin of northeast China possess a natural

sequence of increasing severity of biodegradation. This set of samplesprovides us an opportunity to study the change in oil composition orcompound class distributions with biodegradation severity by negativeion electrospray Fourier transform-ion cyclotron resonance massspectrometry (FT ICR-MS). The bitumen extracts from two columns(Es3 and Es1) were separated into maltene and asphaltene fractionsfor analysis of heteroatomic species by ESI FT-ICR MS. The maltenefractions were found to mainly contain N1, N1O1, N1O2, N1O3, O1,O2, O3 and O4 classes, while the asphaltene fractions mainly containN1, N2O1, N1O1, N1O2, N1O3, N1O4, O2, O3, O4 and O5 classes.These species identified by FT-ICR MS in asphaltene fractions arelikely to be chemisorbed/coprecipitated compounds, or the speciesprecipitated due to high polarity during deasphaltene process. Thesusceptibility of compound classes and homologous series to biode-gradation was studied based on the relative abundances. The results

indicate that microorganisms alter the distribution of acids andnitrogen-containing compounds by selective removal and preservationof certain classes of compounds according to their susceptibility tobiodegradation. For example, O2 and N1O2 classes increase signifi-cantly while N1 and N1O1 classes decrease with biodegradation. Thedifferences in the susceptibility to microbial alteration within acyclicacids, four- or five-ring acids and one- or two-ring acids are discussedand the differences in the susceptibility of homologous series ofheteroatom-containing polycyclic aromatic hydrocarbons are alsodiscussed in this work.

13/00052 Effect of water density and air pressure on partialoxidation of bitumen in supercritical waterSato, T. et al. Fuel, 2012, 95, 347351.Partial oxidation of bitumen was examined in supercritical water from653 to 723 K at a water/oil ratio from 0 to 3 and up to 5.1 MPa of initialair pressure. The contents in the reactor were separated into a water-rich phase and an oil-rich phase. Most of oxygen was consumed within30 min and the main gases produced were CO, CO2and methane. Thelow temperature gave a higher CO/(CO+ CO2) ratio and suppressedcoke formation. The amount of total gas tended to decrease and theratio of CO/(CO + CO2) increased about two times with the increase in

water/ oil ratio from 0.5 to 3. The high water/ oil ratio was prefe rred forselective partial oxidation to produce CO, which means that the effectof the enhancement of partial oxidation by supercritical water wasprobably larger than that of CO oxidation by water and water gas shiftreaction. The increase in initial air pressure increased the amount ofCO and CO2 and decreased the ratio of CO/(CO+ CO2). The totaloxidation route was enhanced under high air pressure.

13/00053 Risk-based optimization of the design of

on-shore pipeline shutdown systemsMedina, H. et al. Journal of Loss Prevention in the Process Industries ,2012, 25, (3), 489493.Crude oil and other liquid materials are transported in large quantitiesthrough pipelines. Pipelines are an efficient and safe transport way ascompared to both rail and road transportation, both from the economicand environmental points of view. Nevertheless, loss of containmentaccidents can occur due to external action a mechanical impact, forexample or to corrosion, aging, etc. Even though the frequency ofsuch events is certainly very low, the effects and consequences onenvironment can be very important. The consequences of accidents inpipelines can be efficiently reduced through a suitable design of the

whole system . O ne of t he points which must be decide d i n t he desig n i sthe installation of blocking valves at appropriate distances, so thatemergency shutdowns can interrupt the flow of substance and isolatethe section where the loss of containment has taken place. In the caseof pipe rupture the amount released is therefore limited to the contentbetween two consecutive valves, usually placed according to heuristiccriteria. However, if too many valves are used, the capital cost ofequipment increases excessively, and if too few are used, the risk of

serious accidents increases. This paper considers the possibility of im-proving the design of such systems by applying risk-based optimizationcriteria. The authors propose an optimization methodology to solvethis conflict by means of an objective function that analyses the varia-tions in overall costs, including the cost of the investment (with specificreference to blocking valves) and the cost of accidents. The result is anoptimum situation in which costs are kept to a minimum. As anexample, the authors apply the methodology to the transportation ofgasoline by pipeline.

13/00054 Settling behavior of spherical particles infiber-containing drilling fluidsElgaddafi, R.et al. Journal of Petroleum Science and Engineering , 2012,8485, 2028.Fibre-containing fluids are utilized in many industrial applications. Inthe petroleum industry, fibre suspensions are used to transport rockcuttings from the bottom of the hole to the surface. Moreover, fibrousfluids are applied in fracturing operations to transport proppantparticles to the fractured space. Solids transport performance of these

fluids largely depends on the settling behaviour of suspended particles.This article presents results of experimental and theoretical investi-gations conducted on the settling behaviour of 28mm sphericalparticles in fibre-containing fluids. Experiments were carried out in a 2-m long and 100-mm diameter transparent cylinder. Both Newtonianand non-Newtonian fluids were tested. A moving digital camera system

was used to track a partic le while it settle d. The camera record s wereused to determine the settling velocity of each particle as a function oftime. Fibre concentration was varied from 0% to 0.08% by weight.When a particle settles in the fibrous fluid, it experiences fibre drag inaddition to conventional hydrodynamic resistance, i.e. viscous drag.Measured terminal velocity was used to compute the viscous com-ponent of the total drag. Subsequently, applying the momentumbalance, the fibre drag component acting on the particle was deter-mined from the total drag. Results show that the fibre drag is a


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function of the particles projected area, settling velocity, fibre dragcoefficient, and density difference between the fluid and particle. Usingexperimental data, a semi-empirical model was developed to predictterminal settling velocity of a particle in fibre-containing fluids. Thecorrelation is valid for both Newtonian and non-Newtonian base fluidsthat have low concentrations of fully dispersed fibres with a length anddiameter of 10 mm and 100 mm, respectively.

13/00055 Soot formation from a distillation cut of aFischerTropsch diesel fuel: a shock tube studyMathieu, O. et al. Combustion and Flame, 2012, 159, (6), 21922201.

The kinetics of soot formation from FischerTropsch (FT) fuels wasstudied in a heated shock tube under homogeneous conditions. Sootinduction delay time and soot yield were measured between 10 and17atm using a distillation cut at 403 K of a FT fuel diesel. Two fuelconcentrations were investigated in pyrolysis: 0.2% and 0.4% FT in Ar.Equivalence ratios () = 18 and 5 were also investigated for the highestfuel concentration. During this study, a second growth of the soot

volume fract ion profi le was obser ved with the highes t fuel concen -tration in pyrolysis and at = 18. It was shown that this second growthappears only at temperatures higher than the temperature at which thesoot yield is at a maximum. Under the conditions investigated, the sootinduction delay time was found not to be very sensitive to the fuelconcentration. A careful analysis of the soot volume fraction profilesshowed that this finding was linked to the measurement method usuallyadopted. Nevertheless, this method was found adequate for asystematic comparison between different fuels or for an investigationof the oxygen concentration effects. The addition of oxygen to themixture promotes soot formation in its early stages by decreasing thesoot induction delay time. A shift of the soot yield curve toward lowertemperatures was also observed. Moreover, oxygen addition reduces

the amount of soot produced. This reduction is proportional to the O 2concentration. Comparisons with literature data showed that a FT fuelprimarily composed ofn-paraffins can be correctly represented by ann-paraffin with a molecular size comparable to the average molecular sizeof the FT fuel. The maximum soot yield of the FT distillation cutstudied was not significantly different from that of a diesel fuelsurrogate previously studied.

13/00056 Variation in abundance and distribution ofdiamondoids during oil crackingFang, C. et al. Organic Geochemistry , 2012, 47, 18.In this study, changes in the abundance and distribution of diamond-oids in petroleum with thermal maturity were investigated by asimulation oil cracking experiment. Highly sensitive and selective gaschromatographytriple quadrupole mass spectrometry (GCMSMS)

was e mploye d to quanti fy di amondoi ds a t ppm and sub-pp m le vels. Theresults indicate that diamondoids were g

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