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Simulation of the NOx emissions during biomass combustion based on Aspen Plus
基于Aspen Plus的生物质燃烧NOx生成模拟

SONG Xinnan,XU huibin,FANG Renjun,WANG Huitong,GU Jiaqiang,

环境科学学报 , 2009,
Abstract: A combustion model of biomass was established based on the software Aspen Plus. The NOx generation from biomass was simulated by this model and the results show good agreement with the experimental data in available in the literature. The amount of NOx produced from biomass combustion increased rapidly with an increase of temperature and air ratio. The simulation approach based on Aspen Plus is flexible and proved to be effective in simulating biomass combustion. Also,by using the flexibility of model param...
Juma Haydary,Tomá? Pavlík
Petroleum and Coal , 2009,
Abstract: Steady-state and dynamic simulation of Preflash and Atmospheric column (Pipestill) in a real crudeoil distillation plant was performed using ASPEN simulations. Steady-state simulation resultsobtained by ASPEN plus were compared to real experimental data. Experimental ASTM D86 curvesof different products were compared to those obtained by simulations. Influence of the steam flowrate in the side stripers and of the heat flow removed in pumparounds was analyzed. Significantinfluence of the heat flow removed in pumparounds on the flow conditions in the column and onthe product composition is explained.Steady-state flowsheet was completed by dynamic simulation requirements and exported to ASPENDynamics for simulations in dynamic mode. The behavior of the products flow rate in dynamicregime was observed after changing the crude oil feed by 10%. Two different control methodsbased on composition (ASTM D86 95% boiling point) and temperature at the second stage wereapplied in dynamic simulation. The time needed to reach a new steady-state, deviation, and abilityof reaching the preset parameters of both methods were compared.
基于Aspen Plus的化学链制氧系统模拟分析  [PDF]
- , 2016, DOI: 10.12068/j.issn.1005-3026.2016.11.011
Abstract: 摘要 在热量分析和压力分析基础上设计了化学链制氧流程,采用流程模拟软件Aspen Plus进行模拟,分析了反应温度,压强对系统能耗的影响并对制氧流程进行优化.结果表明:常压运行时,随着制氧反应温度升高,能耗降低;随着氧化反应温度升高,能耗升高;两个反应器温差越小,能耗越低.负压运行时,随着制氧反应器压强的降低,能耗降低;正压运行时,随着氧化反应器压强的增加,系统能耗呈先降低后升高的趋势.依据上述研究结果,得到了制氧反应器负压运行、氧化反应器正压运行系统的优化操作参数.
Abstract:The chemical looping oxygen production system was designed based on thermal analysis and pressure analysis .Then Aspen Plus chemical process simulation software is used to simulate and analyze the influence of reactor temperature and pressure on system energy consumption in order to optimize the oxygen production system. The results show that under ordinary pressure with the increasing of oxygen reactor temperature the system energy consumption decreases; whereas with the increasing of oxidation reactor temperature the energy consumption increases; and also the smaller the difference of temperature between two reactors is, the lower the system energy consumption is. Under negative pressure with the decreasing of the pressure of oxygen reactor, the system energy consumption decreases. However, under positive pressure with the increasing of the pressure of oxidation reactor, the energy consumption first decreases and then increases. Therefore, the optimization of operating parameters can be obtained in the oxygen production system where oxygen reactor runs under negative pressure and oxidation reactor under positive pressure.
Simulation of Synthesis Gas Production from Steam Oxygen Gasification of Colombian Coal Using Aspen Plus?  [PDF]
Jorge E. Preciado,John J. Ortiz-Martinez,Juan C. Gonzalez-Rivera,Rocio Sierra-Ramirez,Gerardo Gordillo
Energies , 2012, DOI: 10.3390/en5124924
Abstract: A steady state simulation of syngas production from a Steam Oxygen Gasification process using commercial technologies was performed using Aspen Plus ?. For the simulation, the average proximate and ultimate compositions of bituminous coal obtained from the Colombian Andean region were employed. The simulation was applied to conduct sensitivity analyses in the O 2 to coal mass ratio, coal slurry concentration, WGS operating temperature and WGS steam to dry gas molar ratio (SDG) over the key parameters: syngas molar composition, overall CO conversion in the WGS reactors, H 2 rich-syngas lower heating value (LHV) and thermal efficiency. The achieved information allows the selection of critical operating conditions leading to improve system efficiency and environmental performance. The results indicate that the oxygen to carbon ratio is a key variable as it affects significantly both the LHV and thermal efficiency. Nevertheless, the process becomes almost insensitive to SDG values higher than 2. Finally, a thermal efficiency of 62.6% can be reached. This result corresponds to a slurry solid concentration of 0.65, a WGS process SDG of 0.59, and a LTS reactor operating temperature of 473 K. With these fixed variables, a syngas with H 2 molar composition of 92.2% and LHV of 12 MJ Nm ?3 was attained.
A Simulation Study of Downdraft Gasification of Oil-Palm Fronds using ASPEN PLUS  [PDF]
Samson Mekbib Atnaw,Shaharin Anwar Sulaiman,Suzana Yusup
Journal of Applied Sciences , 2011,
Abstract: The use of biomass gasification for conversion of hydrocarbons to permanent fuel gas mainly composed of carbon monoxide and hydrogen, dates back to late 1700. However, the successful design and operation of gasifiers is not an easy task. No clear cut methods of performance prediction of gasifiers is yet available as the thermodynamics of gasifier operation is less understood and highly dependent on the specific biomass feedstock used. In this study, the performance study of downdraft gasification of oil-palm fronds, is carried out making use of ASPEN PLUS 0process simulator software, to study the effect of operating conditions (zone temperature, operating pressure, air fuel ratio and moisture content) on syngas composition. In this study, the pyrolysis yield is calculated from the ultimate analysis (CHNS test) values of the oil-palm fronds, rather than approximating typical yield distribution for pyrolysis products. The results of the simulation showed better agreement with the syngas composition results of other authors. From the simulation study it is shown that higher mass fraction of CO and CH4 can be obtained at lower air-fuel ratio and lower pressure (below 5 bars). The mass fraction of CO increases sharply with increase in the oxidation zone temperature, for the temperature range of 500-700C.
Waste Biomass Gasification Simulation Using Aspen Plus: Performance Evaluation of Wood Chips, Sawdust and Mixed Paper Wastes  [PDF]
Sahar Safarian, Christiaan Richter, Runar Unnthorsson
Journal of Power and Energy Engineering (JPEE) , 2019, DOI: 10.4236/jpee.2019.76002
Abstract: Biomass is one of the most widely available energy sources and gasification is a thermal conversion process where biomass is transformed into a fuel gas with a gasifying agent. In this paper by using ASPEN Plus, a new steady state simulation model for down draft waste biomass gasification was developed. The model that is stoichiometric equilibrium-based is proposed to be used for optimization of the gasifier performance. Prediction accuracy of the model is validated by comparing with available experimental and modeling results in other literature. Then the model is used for comparative analysis of the gasification performance of sawdust, wood chips and mixed paper wastes. In the model, the operating parameters of temperature and equivalence ratio (ER) have been varied over wide range and their effect on syngas composition, syngas yield, low heating value (LHV) of syngas and cold gas efficiency (CGE) has been investigated. Raise in temperature increases the production of CO and H2 which leads to higher syngas yield, LHV and CGE. However, increasing ER decreases the production of CO and H2 which results lessens in LHV and CGE but syngas yield continuously increases because more oxygen is available for biomass reactions at high ER. The optimal values of CO and H2 mole fraction and CGE of sawdust, wood chips and mixed paper wastes are located at 900°C, 1000°C and 1000°C, respectively and ER range is between 0.20 - 0.35 regardless of the kind of biomass which is used as the feedstock.
Preliminary Design of Semi-Batch Reactor for Synthesis 1,3-Dichloro-2-Propanol Using Aspen Plus  [cached]
Robiah Yunus Herliati,A.S. Intan,Z.Z. Abidin,Dzulkefly Kuang
International Journal of Chemistry , 2011, DOI: 10.5539/ijc.v3n1p196
Abstract: Glycerin is a key byproduct from the biodiesel production process. Due to the rapid growth in biodiesel production, the market has been flooded with the crude natural glycerin. This crude glycerin (glycerol) has a very low value because of its impurities, and consequently, a great interest has emerged in the development of technology for alternative uses of glycerol. Among the various possibilities, a technology to convert glycerol to 1,3-dichloro-2-propanol has caught our attention. This compound can be subsequently converted into epichlorohydrin, which is an important intermediate in the production of epoxy resins. 1,3-dichloro-2-propanol is currently being synthesize from propylene via allyl chloride route. However, our technology uses crude natural glycerin, the byproduct of biodiesel production plant, as the starting material and hydrochloric acid as the reagent. The present paper discusses the simulation work on the semi-batch reactor for the production of 1,3-dichloro-2-propanol using ASPEN PLUS. The simulation results were then compared with the experimental data.
Simula??o operacional de uma torre de destila??o atmosférica via Aspen Plus e avalia??o de modelos de analisadores virtuais
Diehl, F.C.;Secchi, A.R.;Lusa, L.P.;Muniz, L.A.R.;Longhi, L.G.S.;
Sba: Controle & Automa??o Sociedade Brasileira de Automatica , 2009, DOI: 10.1590/S0103-17592009000300003
Abstract: the atmospheric tower is one of the most important equipments of an unit of distillation of raw oil in a refinery. the optimization of the operation of this equipment is a constant goal in this industry type, because it makes possible plenty financial returns attractive. to take the operation of the close column of atmospheric distillation to its optimal operational point it is necessary to measure some key properties, in real time, for the performance of the control system. however some properties are not measured easily in real time, or still its measurement depends on the purchase of on-line analyzers that they can present expressive costs. an alternative for the obtaining of those properties is the use of inferences (virtual analyzers), that predict the variable wanted through mathematical models using secondary variables as entrance parameters. two inferences, granted by refap s/a, were appraised with the purpose of determining that with larger predictive power of the temperature that distils 85% of the current of wanted hydrocarbons (t85%). the source of data, for the tests, it was originated in the stationary state by the software aspen plus, after the validation of a model for medium operational data collected in the own refinery. two operational manners were proposed and sensibility analyses were generated so that their results were used as source of data for the inferential models. t85% coming of the simulator were considered pattern for the comparison with the results obtained by the inferences. the virtual analyzers were shown sensitive to the operation way the one that is submitted. this means that the adjustments done in the parameters of the models should be reviewed in case there is a significant operational change in the distillation system. for the operation in that the models were developed the acting of the two inferences was similar, could conclude that in the stationary state the predictions of both are satisfactory.
Abaxial Greening Phenotype in Hybrid Aspen  [PDF]
Julia S. Nowak,Carl J. Douglas,Quentin C.B. Cronk
Plants , 2013, DOI: 10.3390/plants2020279
Abstract: The typical angiosperm leaf, as in Arabidopsis, is bifacial consisting of top (adaxial) and bottom (abaxial) surfaces readily distinguishable by the underlying cell type (palisade and spongy mesophyll, respectively). Species of the genus Populus have leaves that are either conventionally bifacial or isobilateral. Isobilateral leaves have palisade mesophyll on the top and bottom of the leaf, making the two sides virtually indistinguishable at the macroscopic level. In poplars this has been termed the “abaxial greening” phenotype. Previous work has implicated ASYMMETRIC LEAVES1 ( AS1) as an essential determinant of palisade mesophyll development. This gene, as well as other genes (84 in all) putatively involved in setting the dorsiventral axis of leaves, were investigated in two Populus species: black cottonwood ( Populus trichocarpa) and hybrid aspen ( P. tremula x tremuloides), representative of each leaf type (bifacial and isobilateral, respectively). Poplar orthologs of AS1 have significantly higher expression in aspen leaf blade and lower in the petiole, suggestive of a potential role in the isobilateral leaf phenotype consistent with the previously observed phenotypes. Furthermore, an ABERRANT TESTA SHAPE ( ATS) ortholog has significantly lower expression in aspen leaf tissue, also suggesting a possible contribution of this gene to abaxial greening.
Regional Assessment of Aspen Change and Spatial Variability on Decadal Time Scales  [PDF]
Temuulen Tsagaan Sankey
Remote Sensing , 2009, DOI: 10.3390/rs1040896
Abstract: Quaking aspen (Populus tremuloides) is commonly believed to be declining throughout western North America. Using a historical vegetation map and Landsat TM5 imagery, this study detects changes in regional aspen cover over two different time periods of 85 and 18 years and examines aspen change patterns with biophysical variables in the Targhee National Forest of eastern Idaho, USA. A subpixel classification approach was successfully used to classify aspen. The results indicate greater spatial variability in regional aspen change patterns than indicated by local-scale studies. The observed spatial variability appears to be an inherent pattern in regional aspen dynamics, which interacts with biophysical variables, but persists over time.
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