bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Ash Components on the Ignition and Burnout of High Ash Coals
Authors: Feng B. , Yan R. , Zheng C. G. 
Published: August 2010

AbstractThe effect of the ash components on the ignition and burnout of four Chinese high ash coals were studied by thermogravimetric analysis. To investigate the influence of the ash components, comparative experiments were carried out with original, deashed and impregnated coals. Eleven types of ash components, such as SiO2, CaCO3, MgO, Na2CO3, K2CO3, Al2O3, TiO2, Fe2O3, FeS2, NH4Fe(SO4)2. 12H2O and FeSO4(NH4). 6H2O were used in the present study. It was found that most of the ash components have negative effects. The strong influence of some ash components suggests that the combustion characteristics of high ash coal may be determined by the ash composition.
Synthesis Gas Production Using Carbon Dioxide as a Source of Carbon—Current Research and Perspectives
Authors: Max Lu G.Q. , Wang S. 
Published: August 2010

AbstractCO2 is a major greenhouse gas, but it is also an important source of carbon. Catalytic reforming of methane with CO2 to synthesis gas is a promising technology in utilisation of CO2. This process has attracted increasing attention among the research communities in the world, and much progress has been made. This paper presents an overview on the recent advances in catalyst development, reaction mechanism and kinetics. It is found that catalytic activity and stability strongly depend on the nature of support, metal‐support interaction, metal precursor and addition of promoters. Further fundamental research on the reaction and coking mechanisms and kinetics will lead to a high performance catalyst system that will deliver high conversion at low temneratures and with lone‐term cokine‐free oDeration.
Emission Control During Co‐Combustion of Coal and Biomass in a Fluidized Bed Combustor
Authors: Wang Jinghong , Liu Hao , Lu Jidong , Liu Dechang , Xia Xiaotao , Ma Liqiang 
Published: August 2010

AbstractCo‐combustion of coal and biomass in a bench‐scale bubbling fluidized bed was carried out to investigate the effects of co‐combustion on emissions of NOx, N2O and SOx. The objective of these experiments was to find a feasible method of simultaneous NOx/N2O/SOx control. Several coals and coal chars were used and mixed with wood chip and rice husk respectively. The influences of temperature, coal property and fraction of biomass on emissions were investigated.The experimental results revealed that co‐combustion of coal and wood chip or rice husk could reduce NOx/N2O/SOx emissions simultaneously compared to combustion of coal alone. The effect of emission reduction depended on the coal property. The higher the fuel‐N and the lower the volatile matter (VM) content of the coal, the greater the emission reduction. Moreover, the higher the fraction of biomass (wood chip or rice husk), the lower the NOx/N2O/SOx emissions. In addition, it was found that when co‐combusting coal char and wood chip or rice husk, NOx and N2O as well as SOx could be reduced compared to combustion of coal char alone. From the experiments, it was found that heterogeneous reactions played an important role in N2O reduction during co‐combustion of coal and biomass.Hence the process has been proved to be a feasible, economical and promising technique for simultaneous NOx/N2O/SOx control.
Numerical Simulation of NOx Emission from Char Combustion with Detailed Gas Phase Mechanisms
Authors: Feng B. , Zhou Y.B. , Shi X.F. , Zheng C.G. , Okazaki K. 
Published: August 2010

AbstractThe present paper proposed a mathematical model for the simulation of NOx emission from char combustion. The one‐dimensional two‐phase model developed by Kuo [9] was simplified, and a detailed gas‐phase reaction scheme was included, based on the work of Miller and Bowman [19] with updated reaction rates of some important reactions. The scheme includes 289 reactions and 51 species. Two global models for char oxidation were used and compared. The heterogeneous formation of NOx from char oxidation, the reaction of NOx destruction on the char surface, and the reaction of NO destruction by CO catalysed by char were taken into account during char combustion. Our work showed that NOx destruction is sensitive to the char oxidation rate. The heterogeneous reactions for both char oxidation and for NOx formation and destruction require further investigation.
Designing a Process Hazards Analysis Programme in the Microelectronics Industry
Authors: Mckay Gordon 
Published: August 2010

AbstractA Process Hazard Analysis (PHA) component has been developed and implemented as part of a Process Safety Management Programme (PSMP) for a microelectronics company producing wafers in a plant employing over 2,500 people and having a capital investment of US$16.5 billion. Initially a review of the existing PSMP system was carried out, and key sectors of concern were identified. The main area identified for detailed study was the area of Process Hazards Analysis (PHA) to cover a number of interacting departments responsible for designing and implementing new projects and process changes.To create awareness and develop PHA expertise in the company, a training programme was designed and presented to each of the Process, Safety and Environmental, Projects Maintenance and Operations Departments. Basically these five departments were involved in handling well over 100 new projects per year ranging in value from US$50,000 to US$1,000,000 each.The company has implemented a detailed PHA procedure to ensure full and appropriate safety measures are assessed in an economic manner prior to project implementation, as an integral part of the company PSMP. The essential element of the programme is that a HAZOP Study is required for all projects involving chemicals. For small projects, a specialist “Small Project HAZOP Group” was established and specialist training provided.
Improving Management Control of Process Hazards through Structured Monitoring and Auditing Protocols
Authors: Cao J. , Tweeddale H. M. , Walsh P. K. 
Published: August 2010

AbstractThis paper describes an integrated, computer‐based approach to improved management control of process hazards, through generation of structured protocols for monitoring and auditing of process safety. These protocols are developed to match the plant‐specific hazards which are identified by three diverse methodologies operating in parallel with their results collated and sorted. They draw on databases that contain (a) checklists of generic hardware and software topics to be routinely monitored, and (b) checklists of generic topics to be periodically audited. A calculated frequency of monitoring is displayed, together with a suggested frequency from the database, as an aid to experienced judgement. The content of the protocol for any particular audit is determined both by the plant‐specific hazards and the consequent monitoring protocol, together with a Monte Carlo process of selection from a longer list of possible audit topics. The probability of inclusion of any particular audit topic being preset between zero and unity. A case study is described.
A Model of Heat Transfer Across an Epoxy Based Fire Retardant Layer Undergoing Sublimation, Intumescence and Degradation
Authors: Bhargava A. , Griffin G. J. , Green J. C. A. 
Published: August 2010

AbstractA model has been developed to predict the rate of heat flux through fire retardant coatings subjected to a surface flame at 1080°C. The model includes the effect of the material subliming, intumescing and degrading, and of temperature effects on the material properties. Temperature profiles were compared with experimental data obtained on commercial fire retardants using a small‐scale fire testing apparatus developed for the study of passive fire protection materials. Temperature predictions of the model agreed within 10% of experimental results except when erosion and cracking of the retardant was observed.
Effect of Ullage on Properties of Small‐Scale Pool Fires
Authors: Dlugogorski B. Z. , Wilson M. 
Published: August 2010

AbstractAn experimental technique is described for accurately measuring the steady‐state fuel consumption rates in small‐scale pool fires, less than 7 cm diameter. The technique is applied to studying ethanol fires burning in cylindrical vessels constructed from various materials. The results indicate that the distance between the top of a vessel and the fuel surface profoundly influences the properties of liquid pool fires, including their structure and their burning rates. For combustion in glass cylinders, the burning rates decrease exponentially with increasing freeboard until a critical ullage is attained. At this ullage, the fuel begins to burn on the inside of the vessel, and the burning rate tends to increase slightly. With a further increase of the lip height, flame instabilities develop leading ultimately to flame self‐extinction. The exponential decline in fuel consumption with the lip height depends strongly on the vessel material of construction. For fires in cylinders constructed from better conducting materials (copper and mild steel), the ethanol starts to boil beyond a certain ullage. The appearance of this phenomenon redefines the fuel consumption curve. Finally, free convection leads to non‐negligible heat losses, especially from the more conducting copper and steel vessels, with the burning rates becoming dependent on the outside surface area of the cylinders.
Fundamental Investigation of Microwave Pretreatment on the Flotation of Massive Ilmenite Ores
Authors: Fan X. , Rowson N. A. 
Published: August 2010

AbstractMicrowave energy was used as a novel method to modify massive ilmenite surface properties and improve ilmenite flotation. Studies concentrated on an investigation into the effect of microwave radiation pre‐treatment on the flotation behaviour of a massive ilmenite ore sample from Norway. Experimental programmes were carried out in both Hallimond‐tube and Denver‐cell flotation devices.The experimental results indicate that the flotability of massive ilmenite was greatly improved after microwave‐induced thermal pretreatment. In comparison with conventional flotation, at the same optimised flotation conditions, massive ilmenite subjected to microwave heat treatments floated well in both the roughing and cleaning stages. Ilmenite recoveries were greatly increased over non‐treated samples. The major factors affecting ilmenite microwave‐pretreatment flotation are microwave power level and irradiation time.The investigation into the surface zeta potential indicates that microwave irradiation enhanced the adsorption of oleate ions in the Helmholtz layer of the ilmenite particles and resulted in ilmenite surface charge being more negative. Improved ilmenite flotation recovery was observed after microwave pretreatment.
Experimental and Mechanism Studies on a Different‐Velocity Circulating Fluidized Bed for Flue Gas Desulfurization
Authors: Wu Y. H. , Feng B. , Huang Z. , Li D. J. 
Published: August 2010

AbstractExperimental studies of flue gas desulfurization were carried out in a different‐velocity circulating fluidized bed reactor, using dry slaked lime as the sorbent. S02 removal efficiency could be as greater than 80% when the Ca/S molar ratio was 1.1, and when a small amount of water was added into the process. By considering the main aspects that influence desulfurization efficiency in the experiment, it was found that the water sprayed into the reactor plays an important role. In addition, a preliminary investigation was performed on the desulfurization mechanism. The desulfurization reaction occurs quickly in the water film on the surface of the sorbent.
Direct Numerical Simulation of Dense Gas‐Solid Two‐Phase Flows
Authors: Zhulin Y. 
Published: August 2010

AbstractBased on Newton's law and the classical physical laws, Eulerian and Lagrangian methods are respectively used to deal with gas‐field and discrete particles. The three‐dimensional viscid air‐field and three‐dimensional discrete particle field are solved in each time step Δt. Collision and friction between individual particles are taken into account when establishing the mathematical models, including individual particle diameter, density, stiffness and friction coefficient. Particles mixing in ball mills, particles dropping from hoppers, and particles fluidizing in fluidized beds are used as examples of the simulations. Selected simulated results are compared to experimental results.
Low Temperature Pyrolysis of an Australian Brown Coal in a Fluidised Bed Reactor
Authors: Shen L. , Zhang D. K. , Yan H. M. , Roach J. R. , Nguyen Q. D. 
Published: August 2010

AbstractThe pyrolysis of Loy Yang coal was investigated under rapid heating conditions in a fluidised bed with a feed rate of 10g/h. Nitrogen was used as the fluidising gas operating at fives times the minimum fluidising velocity. The yields of tar, total volatile matter and C1‐C3 hydrocarbons are obtained for pyrolysis temperatures between 300 to 600°C. A maximum tar yield of 24.3% w/w (dry ash‐free coal) was achieved at 550°C and 1.82 s gas residence time. Fourteen fractions were identified in the tar dissolved in methanol. Yields of C1‐C3 hydrocarbons increased with increasing temperature to 3% w/w at 600°C. Elemental analysis showed that the composition of char and the tar yields were strongly dependent on temperature. The effects of gas residence time and feed particle size were also investigated.
Photodegradation of the Volatile Organic Compounds in the Gas Phase: A Review
Authors: Ray Madhumita Bhowmick 
Published: August 2010

AbstractA review of photodegradation processes suitable for the treatment of Volatile Organic Compounds (VOCs) present in the effluents from air‐stripping and soil‐vapor extraction is presented. This paper outlines and summarizes the essential factors such as kinetics and mechanism, intermediates of degradation processes, and reactor modeling which lead to the successful application of this useful technology. In addition, the effects of operating parameters such as humidity, temperature, additives and types of VOCs are discussed. The review also identifies the areas where further work is needed.
Heterogeneous Photocatalysis in Environmental Remediation
Authors: Chen Dingwang , Sivakumar M. , Ray Ajay K. 
Published: August 2010

AbstractSemiconductor‐based photocatalytic processes have been studied for nearly 15 years due to their many intriguing advantages in environmental remediation and other areas. In this paper, underlying principles and mechanism of the photocatalytic degradation process were discussed, followed by thermodynamics, kinetics, mass transfer effects were discussed. The kinetics of photocatalytic degradation was analysed with the aim of determining the favourable conditions to obtain high quantum yield. Primary parameters that influence the process such as catalyst loading, dissolved oxygen, pH, temperature, light intensity, crystalline structure, etc. have been discussed in detail. Different types of photocatalytic reactors, process efficiencies and applications in environmental engineering as well as in other areas have also been mentioned. The main barrier to the commercialization of the processes is the low quantum yield. However, it is expected that large‐scale applications could be achieved with significant progress by improvement of process performance.
The Effect of Additives and Impurities on the Partition of Ethanol into n‐Decanol from Aqueous Solutions
Authors: Carolan N. , Weatherley L.R. 
Published: August 2010

AbstractThe recovery of biological products from fermentation media by direct liquid‐liquid extraction is complicated by the presence of impurities. These may comprise either side products of the bio‐transformation or residual species from the pre‐fermentation substrates. As a corollary to the detrimental effect of impurities upon extraction, addition of reagents, for example salts, can be used to enhance the extraction and mitigate to some extent against these. This paper describes an experimental study of the partitioning of ethanol from aqueous solutions into 1–decanol. Specific groups of impurities and additives were identified, comprsing: electrolyte compounds (including acids, bases, and salts), ionic and non‐ionic surfactants, commercial de‐emulsifiers, organic acids, polysaccharide compounds (i.e. sugars and starch), protein, biomass (including yeast and bacteria), and 1–propanol. A number of thermodynamic models for predicting the effect of each additive on the phase distribution behaviour of ethanol were screened and tested. The additives considered in this paper are confined to those of relatively simple chemical structure and included 1–propanol, oleic acid, glucose, sodium chloride, sodium hydroxide, calcium chloride, ammonium chloride, ammonium sulphate, and hydrochloric acid. These were added in controlled amounts to the principal extraction system components and the effect upon the partition coefficients of ethanol determined.
Robust Digital PI Control for Uncertain Time‐delay Systems in Process Industry
Authors: Liu Xiang , Wang Wenhai , Sun Youxian 
Published: August 2010

AbstractA new robust digital PI controller for a class of typical systems with uncertain time delays is developed for use in process industry. Using this Controller the satisfactory locations of poles of the closed‐loop systems will change slowly with the varied time delays, and the robust stability is guaranteed for the time varied time‐delay on a large scale. Simulation results show that the robust controller also works for the systems in the presence of unmodelled dynamics.
Modeling of Fourdrinier and Cylinder Machines
Authors: Zhang W.D. , Xu X.M. , Sun Y.X. 
Published: August 2010

AbstractIn this paper, an “equivalent paper machine” is presented which possesses the features of both the fourdrinier machines and cylinder machines, and a universal model is developed by mechanism analysis. The model is not only an external description as often obtained by system identification, but an internal one in which internal process variables are included. Experiments show that the model agrees closely with the plant data.
A Modified Augmented Lagrange Multiplier Method for Large‐Scale Optimization
Authors: Liang Ximing , Hu Jianbo , Zhong Weitao , Qian Jixin 
Published: August 2010

AbstractA modified augmented Lagrange multiplier method for large‐scale nonlinear optimization problem is studied in this paper. The basic steps of the proposed algorithm comprise an outer iteration, in which the Lagrange multipliers and various penalty parameters are updated, and an inner iteration, in which a nonlinear optimization with simple bound constraints is solved. The algoritm presented has been implemented in a general routine denoted as MALMM. Numerical results are presented for a variety of problems, which show the stability and effectiveness of the algorithm in large‐scale problems.
H∞Control of Discrete Time Linear Systems Subject to Input Saturation
Authors: Xiong Xuequan , Xue Anke , Sun Youxian 
Published: August 2010

AbstractIn this paper, we consider the H∞control problem of discrete‐time linear systems subject to input saturation. Some sufficient conditions are derived which make the closed‐loop system satisfy local asymptotically stability and the H∞performance prior given. According to these sufficient conditions, the synthesis of state feedback controller is considered. All of the results are described in LMI.
Self‐Desulphurization and Self‐Denitrification Properties and Mechanisms in Biobriquette Combustion
Authors: Kim Hee‐Joon , Lu Guo‐Qing , Maruchi Hidenobu , Li Tian‐Ji , Noda Hiroyuki , Sadakata Masayoshi 
Published: August 2010

AbstractTo control pollutant emissions from the combustion of both domestic stoves and small‐capacity industrial boilers, a new artificial solid fuel called biobriquette with self‐denitrification and self‐desulphurization has been developed. It is manufactured from a mixture of coal, biomass (agricultural wastes, cornstalk, etc.), desulphurizer and denitrificator such as limestone, seashell and pulp black liquid (industrial wastes) under a high compression pressure. In this study, the experiments of briquetting, pyrolysis and combustion were performed in order to reveal its characteristics of briquetting, self‐denitrification and self‐desulphurization.The main results are that pulp black liquid and/or biomass improves the briquetting and combustion of biobriquette. The seashell called scallop has high desulphurization efficiency, but they only slightly reduce NOx emissions in biobriquette combustion. The pulp black liquid mixed in the biobriquette has not only a good desulphurization but also significant denitrification result. The denitrification reaction happens mainly in the char combustion stage and slightly in the volatile combustion stage. The denitrification efficiency of about 40% can be obtained when the mixture reaches 10 mass%. The main mechanism of denitrification was considered to originate from NH3 and NaOH included in the pulp black liquid.
Effect of Char Properties on N2O Formation and Reduction during Circulating Fluidized Bed Coal Combustion
Authors: Liu Hao , Kojima Toshinori , Feng Bo , Liu Dechang , Lu Jidong 
Published: August 2010

AbstractThe mechanism and effect of char on N2O formation and reduction during circulating fluidized bed coal combustion were examined in a bench‐scale circulating fluidized bed. It was found that char derived from coal with high volatile matter content has a higher conversion ratio from char‐N into N2O during char combustion. Furthermore, char with greater pore volume and specific surface area not only shows a higher conversion ratio from char‐N into N2O, but also has stronger N2O reduction ability. Big pores play the main part in N2O diffusion inside char particles whereas small pores play the main part of chemical reaction. Molecular diffusion and Knudsen diffusion are both important for N2O diffusion in char. The reactivity of char concerning N2O formation and reduction is closely related to its pore characteristics, which is an important factor to account for the diverse N2O emissions from combustion of various coals in a circulating fluidized bed.
Investigation and Application of “Bluff‐body in Cavity” Burner for Pulverized Coal Combustion
Authors: Chen Gang , Qiu Ji‐Hua , Xu Ming‐Hou , Zheng Chu‐Guang 
Published: August 2010

AbstractThe flow and combustion process of a new type of pulverized coal burner, the “bluff‐body in cavity”, is studied in this paper. This is an improvement on the basic principle of the ordinary bluff‐body burner. Mean and fluctuating velocity components and turbulence characteristics of the flow in the outlet of the “bluff‐body in cavity” burner were measured using a three‐dimensional laser particle dynamics anemometer (3D‐PDA). Combustion tests showed that this burner is better than an ordinary burner with only a bluff‐body regarding the ignition and flame stability. Application of this new burner in several power plant boilers (65‐670 t/h) showed that the temperature in the flame zone is high, the combustion process is very stable, and the boiler efficiency is increased. These improvements indicate a promising future for the burner.
Modelling and Simulation of a Top‐Fired Primary Steam Reformer using GPROMS
Authors: Dunn A.J. , Yustos J. , Mujtaba I.M. 
Published: August 2010

AbstractA top‐fired primary steam reformer is modelled and simulated using gPROMS, a general purpose modelling package Validation of the model is performed against industrial data A sensitivity analysis of the key operating parameters of pressure, temperature, steam to carbon ratio, and feed rate are comparable to previous observations in the published literature Optimisation of the burner profile and the reactant gas distribution enhanced the balance of the furnace, which will significantly improve the operating lifetime of the steam reformer for a given performance